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  • Springer  (177,357)
  • Blackwell Publishing Ltd  (11,951)
  • American Association of Petroleum Geologists (AAPG)
  • 1970-1974  (189,308)
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  • 1
    Electronic Resource
    Electronic Resource
    Oxford, UK : Blackwell Publishing Ltd
    The @photogrammetric record 8 (1974), S. 0 
    ISSN: 1477-9730
    Source: Blackwell Publishing Journal Backfiles 1879-2005
    Topics: Architecture, Civil Engineering, Surveying
    Notes: Distinct benefits have been obtained from the use of orthophotography in the initial planning of Scotland's sixth new town, to be located at Stonehouse, 29 km south east of Glasgow, due to a comprehensive approach to the mapping requirements. This paper discusses some of the details of the orthophotomapping project.〈section xml:id="abs1-2"〉〈title type="main"〉RésuméL'orthophotographie s'est révélée d'un usage fort intéressant pour les études d'implantation de la sixième ville nouvelle d'Écosse (Stonehouse, 29 km au S.E. de Glasgow). On discute quelques aspects du projet d'orthophotoplan.〈section xml:id="abs1-3"〉〈title type="main"〉ZusammenfassungDeutliche Vorteile ergaben sich aus der Anwendung der Differentialent-zerrung bei der Vorplanung für Schottlands 6. neue Stadt, die in der Nähe von Stonehouse, 29 km südöstlich von Glasgow liegen soll, infolge der umfassenden Befriedigung der Anforderungen an die Kartenherstellung. Im Artikel werden einige Details des Orthophotokarten-Projektes diskutiert.
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  • 2
    Electronic Resource
    Electronic Resource
    Oxford, UK : Blackwell Publishing Ltd
    The @photogrammetric record 8 (1974), S. 0 
    ISSN: 1477-9730
    Source: Blackwell Publishing Journal Backfiles 1879-2005
    Topics: Architecture, Civil Engineering, Surveying
    Notes: This paper describes work carried out jointly by the British Ship Research Association and the author to assess the value of photogrammetry in acquiring quality control measurements on large steel structures in the shipbuilding industry. In particular, the feasibility of using photogrammetry to resolve one of the problems of joining half ships afloat (that is the dimensional equivalence of the mating faces) is investigated.〈section xml:id="abs1-2"〉〈title type="main"〉Résumé On décrit le travail mené conjointement par la British Ship Research Association et l'auteur pour tester la valeur des méthodes photogrammétriques dans le contrôle de précision de grandes structures d'acier (industrie navale). En particulier on a cherché dans quelles mesure on pouvait utiliser la photogrammétrie pour vérifier la conformité de piéces devant entrer en jonction.〈section xml:id="abs1-3"〉〈title type="main"〉Zusammenfassung Im Artikel werden die gemeinsam vom Autor und der British Ship Research Association durchgeführten Untersuchungen zwecks Eignung der Photogrammetrie bei Gütekontrollen grosser Stahlkonstruktionen im Schiffbau beschrieben. Insbesondere wurde die Anwendungsmöglichkeit der Photogrammetrie bei der Lösung einiger der beim Verbinden schwimmender halber Schiffe auftretenden Probleme untersucht (um die Grössenordnung der Aufnahmeobjekte zu veranschaulichen).
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  • 3
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    Oxford, UK : Blackwell Publishing Ltd
    The @photogrammetric record 8 (1974), S. 0 
    ISSN: 1477-9730
    Source: Blackwell Publishing Journal Backfiles 1879-2005
    Topics: Architecture, Civil Engineering, Surveying
    Notes: The Photogrammetric Society was honoured to be addressed by the Congress Director of the International Society for Photogrammetry during March 1974. Professor Halonen's lecture covered several aspects of current photogrammetric research in Finland. The following account contains contributions by two of his colleagues, J. Hakkarainen and H. Salmenperä, on specific aspects of lens distortion and block adjustment.
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  • 4
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    Oxford, UK : Blackwell Publishing Ltd
    The @photogrammetric record 8 (1974), S. 0 
    ISSN: 1477-9730
    Source: Blackwell Publishing Journal Backfiles 1879-2005
    Topics: Architecture, Civil Engineering, Surveying
    Notes: The current methods for describing and comparing shapes of teeth have a number of inadequacies which lead to inaccuracy and misinterpretation. A method is described which depends on co-ordinate information. Stereoscopic microphotography of teeth crowns is used to take co-ordinates of up to 600 points on the tooth surface. Mathematical surfaces are fitted to the co-ordinates by the method of least squares and analysed by trend surface analysis. The results show that this is a useful method of describing a complex shape, although there are problems which render comparison more difficult.〈section xml:id="abs1-2"〉〈title type="main"〉RésuméLes méthodes qu'on utilise généralement pour décrire et comparer les formes des dents sont de par leur nature imprécises et peu sûres. On décrit une méthode basée sur l'utilisation de coordonnées tridimensionnelles. A partir de micro-stéréogrammes de couronnes dentaires, on relève les coordonnées de près de 600 points de la surface de la dent. Ce semis est ensuite lissé par des surfaces mathématiques et étudié par les méthodes de l'analyse des surfaces. On conclut qu'il s'agit d'une utile méthode de description d'une forme complexe, quoique les comparaisons de dent à dent restent difficiles.〈section xml:id="abs1-3"〉〈title type="main"〉ZusammenfassungDie gegenwärtigen Methoden zur Beschreibung und zum Vergleich von Zahnformen weisen eine Reihe von Unzulänglichkeiten auf, die zu Ungenauig-keiten und Fehlinterpretationen führen. Es wird ein auf der Koordinatenin-formation beruhendes Verfahren beschrieben. Dabei wird die Stereomikro-photographie von Zahnkronen zur Ermittlung der Koordinaten von bis zu 600 Punkten auf der Zahnoberfläche angewendet. Die mathematische Oberfläche wird mit Hilfe der Methode der kleinsten Quadrate bestmöglich den gegebenen Koordinaten angepasst und durch Oberflächentrendanalyse überprüft. Die Ergebnisse zeigen, dass es sich um ein brauchbares Verfahren zur Beschreibung komplexer Formen handelt, obwohl es einige Probleme gibt, die den Vergleich erschweren.
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  • 5
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    Oxford, UK : Blackwell Publishing Ltd
    The @photogrammetric record 8 (1974), S. 0 
    ISSN: 1477-9730
    Source: Blackwell Publishing Journal Backfiles 1879-2005
    Topics: Architecture, Civil Engineering, Surveying
    Notes: Book Reviewed in this article:TERRAIN EVALUATION. By C. W. Mitchell.ENVIRONMENTAL REMOTE SENSING: APPLICATIONS AND ACHIEVEMENTS. By E. C. Barrett and L. F. Curtis.MULTILINGUAL DICTIONARY OF TECHNICAL TERMS IN CARTOGRAPHY. Compiled by the International Cartographic Association.THE EARTH FROM SPACE. By J. Bodechtel and H. G. Gierloff-Emden.CARTOGRAPHIC DESIGN AND PRODUCTION. By J. S. Keates.
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  • 6
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    Oxford, UK : Blackwell Publishing Ltd
    The @photogrammetric record 8 (1974), S. 0 
    ISSN: 1477-9730
    Source: Blackwell Publishing Journal Backfiles 1879-2005
    Topics: Architecture, Civil Engineering, Surveying
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  • 7
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    Oxford, UK : Blackwell Publishing Ltd
    The @photogrammetric record 8 (1974), S. 0 
    ISSN: 1477-9730
    Source: Blackwell Publishing Journal Backfiles 1879-2005
    Topics: Architecture, Civil Engineering, Surveying
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  • 8
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    Oxford, UK : Blackwell Publishing Ltd
    The @photogrammetric record 8 (1974), S. 0 
    ISSN: 1477-9730
    Source: Blackwell Publishing Journal Backfiles 1879-2005
    Topics: Architecture, Civil Engineering, Surveying
    Notes: In recent years analytical aerial triangulation in the Royal Australian Survey Corps has evolved to an advanced stage. Current procedures are described and future possibilities explored.〈section xml:id="abs1-2"〉〈title type="main"〉Résumé Ces dernières années les techniques d'aerotriangulation analytique, dans le Royal Australian Survey Corps ont beaucoup progressé. On décrit les méthodes employées et on fait quelques prospective.〈section xml:id="abs1-3"〉〈title type="main"〉Zusammensfassung In den letzten Jahren hat die analytische Aerotriangulation beim Royal Australian Survey Corps einen bedeutenden Stand ereicht. Die gegenwärtigen Technologien werden beschrieben und künftige Möglichkeiten untersucht.
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  • 9
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    Oxford, UK : Blackwell Publishing Ltd
    The @photogrammetric record 8 (1974), S. 0 
    ISSN: 1477-9730
    Source: Blackwell Publishing Journal Backfiles 1879-2005
    Topics: Architecture, Civil Engineering, Surveying
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  • 10
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    Oxford, UK : Blackwell Publishing Ltd
    Review of income and wealth 20 (1974), S. 0 
    ISSN: 1475-4991
    Source: Blackwell Publishing Journal Backfiles 1879-2005
    Topics: Economics
    Notes: The central concern of this paper is with the treatment of human resources in dynamic applications of capital and growth accounting. Despite many advances, national accounting conventions still give biased profiles of the economy, but the time is ripe for experimentation with measures that can correct those biases and provide a more adequate base for assessment of long-term economic performance and prospects.In the first section, the logic and feasibility of forward and backward measures of formation of human capital in the simplest case (of full-time schooling) is examined in parallel with physical capital. In a dynamic economy, which is rarely if ever in equilibrium, these approaches complement each other; they are poor substitutes. In section two a number of conceptual and measurement issues are considered with particular reference to human-capital investment periods and the treatment of appreciation, depreciation and obsolescence of human versus physical capital. Here special attention is given to the extended periods of investments in human resources, which overlap with realization of returns, and to the processes and agencies through which postschool investments are made. The last section presents a brief statement concerning asymmetries in disequilibrium biases with respect to the formation of human relative to physical capital. Drawing upon section 1 with regard to forward and backward measures and section 2 with regard to the critical importance of postschool learning, new possibilities in contributions of national accounting to a dynamic analysis of economic development are suggested.
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  • 11
    Electronic Resource
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    Oxford, UK : Blackwell Publishing Ltd
    Review of income and wealth 20 (1974), S. 0 
    ISSN: 1475-4991
    Source: Blackwell Publishing Journal Backfiles 1879-2005
    Topics: Economics
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  • 12
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    Oxford, UK : Blackwell Publishing Ltd
    Review of income and wealth 20 (1974), S. 0 
    ISSN: 1475-4991
    Source: Blackwell Publishing Journal Backfiles 1879-2005
    Topics: Economics
    Notes: After giving a brief discussion of the biases that exist in the conventional estimation procedures followed in the construction of national accounts, this paper argues for restructuring of national accounts so as to treat human capital formation as investment rather than consumption and suggests that a beginning should be made in respect of schooling. The argument is based on the notion that “investment” or “capital” is that which yields future income streams and also on the rather obvious point that treating as consumption large outlays that really constitute investment distorts analyses of resource allocation, growth and income distribution, and obscures intersectoral relations. It is pointed out that the proposed restructuring of national accounts is more relevant and important for developing countries, many of which are embarked on investment planning. Another major point emphasized is that the input of students’time should be properly measured and included in the estimates of capital formation by schooling.To illustrate what these proposals imply, revision has been attempted of the estimates of (a) educational outlay (or activity in the education sector), (b) gross capital formation, and (c) gross national product, pertaining to the national accounts of a major developing country, namely India, for the years 1960–61 through 1965–66. The modified estimates, though first approximations and covering only a part of the human capital formation and having a systematically downward bias, nevertheless indicate an upward revision of the estimate of activity in the education sector by about 200 to 300 percent, of gross capital formation by about 50 percent and of the gross national product by 4 to 7 percent. These magnitudes show the substantial order of distortion involved in the conventional procedures.
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  • 13
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    Oxford, UK : Blackwell Publishing Ltd
    Review of income and wealth 20 (1974), S. 0 
    ISSN: 1475-4991
    Source: Blackwell Publishing Journal Backfiles 1879-2005
    Topics: Economics
    Notes: This paper considers the properties of the Divisia, or chain-link, index, as they relate to the argument that this is the most appropriate index for use in studying the sources of economic growth. The great advantage of the Divisia index is alleged to be its “accuracy”, that is, its capacity to combine time series of prices and quantities to give a true reflection of the height of a utility or production function over time. The paper shows that there are circumstances where the confidence in the accuracy of the Divisia index is justified, but that the conditions required are very restrictive and typically do not obtain in the contexts where the Divisia index is used. Misplaced confidence in the Divisia index has led to errors of interpretation that might otherwise have been avoided, and has given rise to a distorted view of the process of economic growth.
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  • 14
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    Oxford, UK : Blackwell Publishing Ltd
    Review of income and wealth 20 (1974), S. 0 
    ISSN: 1475-4991
    Source: Blackwell Publishing Journal Backfiles 1879-2005
    Topics: Economics
    Notes: This essay focuses on the problems of estimating the share of America's personal wealth in the hands of affluent individuals by a technique known as the estate multiplier method. Rather than exploring these problems in an empirical vacuum, we first present some results from the most recent estimates of the distribution of U.S. personal wealth.1 The estimates—for the year 1969—are then used as a basis for gauging the sensitivity of estate multiplier estimates to variations in approach.Section I presents new empirical findings dealing with the asset holdings of top wealth-holders and the super rich, and with the shares of specific assets owned by them. Also presented is information about the sex and marital status of the super rich.Section II discusses various technical aspects of the estate multiplier as applied to federal estate tax returns. The main concern is with the weighting process, but attention is paid to the fact that estate tax returns filed in a given year are not for decedents who died in that year or any single year, and to the problems of adjusting the face value of life insurance to cash surrender value.
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  • 15
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    Oxford, UK : Blackwell Publishing Ltd
    Review of income and wealth 20 (1974), S. 0 
    ISSN: 1475-4991
    Source: Blackwell Publishing Journal Backfiles 1879-2005
    Topics: Economics
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  • 16
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    Oxford, UK : Blackwell Publishing Ltd
    Review of income and wealth 20 (1974), S. 0 
    ISSN: 1475-4991
    Source: Blackwell Publishing Journal Backfiles 1879-2005
    Topics: Economics
    Notes: The only periodic data available in Canada on the asset holdings and net worth of the household sector are data collected through a series of household surveys originally initiated in 1954. Some limited data on the holdings of financial claims by the personal and unincorporated business sector are available from flow of funds work. Data are unavailable for estimation from estate tax returns.The scope of the surveys has been expanded substantially so that the most recent survey obtained a very comprehensive list of asset holdings. The experience with Canadian surveys has been similar to that of other countries; surveys appear to underestimate asset holdings although the estimates are more reliable for widely held assets than for assets with a very skewed distribution. Nevertheless, the surveys appear to trace the accumulated distribution of personal savings over time to a considerable degree and provide useful cross-sectional trend data.Canadian data show that wealth is more unequally distributed among family units than is income although wealth appears to be more equally distributed between income groups than is income. Wealth is also very unequally distributed within the same income group. Over time, there appears to have been some movement towards a more equal distribution of asset holdings between income groups.
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  • 17
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    Oxford, UK : Blackwell Publishing Ltd
    Review of income and wealth 20 (1974), S. 0 
    ISSN: 1475-4991
    Source: Blackwell Publishing Journal Backfiles 1879-2005
    Topics: Economics
    Notes: 〈blockFixed type="quotation"〉Man may work from sun to sun, But woman's work is never done. Anon.It has become almost a cliché that measured growth in the U.S. is being overstated. The classic on the subject is by Mishan [5], who argues persuasively that the (uncounted) externalities from production in industrialized economies are overtaking the production which these economies are counting. But externalities are not the only problems in measuring economic activity and economic growth. Two other problems of equal importance, but more amenable to measurement, are the distinction between final and intermediate production, and the quantification of nonmarket productive behavior. In this paper, we concentrate on one aspect of the measurement of nonmarket behavior—the value of production at home by housewives./〉Specifically, we will present estimates of the value of home based nonmarket production by housewives. These estimates will then be used to supplement various national product aggregates in order to calculate more accurate growth rates for the U.S. economy. We find that the value of nonmarket production by married women during the 1960's has averaged approximately thirty percent of the GNP and close to 40 percent of the national income. The inclusion of the nonmarket work of housewives in GNP would reduce the measured rate of growth of real GNP per potential worker by about ten percent, the exact amount depending on how the value of nonmarket work is estimated. Our estimates indicate a reduction in the absolute rate of growth of almost 0.25 percent.
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  • 18
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    Oxford, UK : Blackwell Publishing Ltd
    Review of income and wealth 20 (1974), S. 0 
    ISSN: 1475-4991
    Source: Blackwell Publishing Journal Backfiles 1879-2005
    Topics: Economics
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  • 19
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    Oxford, UK : Blackwell Publishing Ltd
    Review of income and wealth 20 (1974), S. 0 
    ISSN: 1475-4991
    Source: Blackwell Publishing Journal Backfiles 1879-2005
    Topics: Economics
    Notes: Some writers have emphasised the adverse environmental and social effects of economic growth, while others have claimed that countries with higher levels of social well-being also tend to enjoy higher levels of per capita output. The aim of this study is to see what statistical light can be thrown on these issues by collating and comparing seventeen different social indicators for twenty countries in two bench-mark years, 1951 and 1969.Two methods of analysing data are employed. First, all the countries are ranked for each indicator in turn for a particular year. Each country is then given a score ranging from 1 to 20 for each indicator, and the scores aggregated over the indicators to obtain an overall ranking score for every country. Secondly, the data are subjected to a principal components analysis to examine the correlation between the indicators. The first principal component is a potential candidate for use as a social index number. Changes in these social variables are then related to the rate of economic growth, and no evidence is found of a negative correlation between economic growth and social development. On the contrary, the results suggest a positive correlation between the two, although the strength of this relationship may be diminishing. It is not claimed that the results are in any sense the most preferred test of the form of the relationship between economic growth and social welfare, which must be a matter for subjective evaluation; rather they are seen as a contribution to the body of empirical evidence on this subject.
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  • 20
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    Oxford, UK : Blackwell Publishing Ltd
    Review of income and wealth 20 (1974), S. 0 
    ISSN: 1475-4991
    Source: Blackwell Publishing Journal Backfiles 1879-2005
    Topics: Economics
    Notes: The paper analyzes annual revisions of figures for G.N.P. and 8 of its components in 40 countries. It arrives at the conclusion that first estimates are very often significantly biased downwards, especially Private Consumption, Fixed Investment, G.D.P. and G.N.P. Also successive revisions are sometimes correlated (negatively in most cases). The distribution of revisions differ as between developed and developing countries.
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  • 21
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    Oxford, UK : Blackwell Publishing Ltd
    Review of income and wealth 20 (1974), S. 0 
    ISSN: 1475-4991
    Source: Blackwell Publishing Journal Backfiles 1879-2005
    Topics: Economics
    Notes: This paper presents the results of applying the mortality multiplier approach to estate duty statistics in order to estimate the size distribution of personal wealth in the Republic of Ireland. It commences with an examination of the limitations of the estate duty statistics, a discussion of the problems involved in collecting the data, and a short consideration of the mortality multipliers used.Estimates are presented for the size distribution of personal wealth, and the distribution of wealth between age groups. Some comparisons are given with wealth in Northern Ireland, Great Britain and the U.S.A. Estimates of the components of personal capital were not found possible.Finally, preliminary estimates are made for the distribution of wealth among married and single persons, in order to provide the basis for an analysis of wealth possessed by wealth-owning units (defined as single males, single females and married couples). By making extreme assumptions, upper and lower limits are placed on the actual pattern of the size distribution of wealth by wealth-owning units.
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  • 22
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    Oxford, UK : Blackwell Publishing Ltd
    Review of income and wealth 20 (1974), S. 0 
    ISSN: 1475-4991
    Source: Blackwell Publishing Journal Backfiles 1879-2005
    Topics: Economics
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  • 23
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    Review of income and wealth 20 (1974), S. 0 
    ISSN: 1475-4991
    Source: Blackwell Publishing Journal Backfiles 1879-2005
    Topics: Economics
    Notes: The basic theme of Mr. Webster's practical and uncontentious paper is that unreliability undermines credibility. In the following comment specific issues he mentions will be considered in more detail to illustrate some of the principal general points made in his paper.
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  • 24
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    Review of income and wealth 20 (1974), S. 0 
    ISSN: 1475-4991
    Source: Blackwell Publishing Journal Backfiles 1879-2005
    Topics: Economics
    Notes: The author addresses himself first to the problem that summary measures of wage income inequality, computed for Kinshasa, the main urban area in Zaire, tend to overstate the degree of total labor income inequality among sharing units of comparable size. It is argued that this is true for two main reasons: (1) earnings from female commercial activity are not recorded in the available statistics; and (2) the 1960 UN definition of household upon which the measures of inequality are based understates the size of the actual sharing unit. Data taken from the 1967 Socio-Demographic Survey of Kinshasa and the 1970 household budget study are used to test these hypotheses regarding short-run income inequality.The policy observation is made that, while modernization of the commodity distribution system may provide a disincentive for sharing and a reduction in opportunities for female employment, investment in non-service sectors may equalize the secular income distribution for a given migration cohort. Evidence of unskilled migrants moving from service to non-service sector employment in response to increased labor demand is presented. This is accomplished by supplementing sample survey data with time series on aggregate employment by sector for Kinshasa.
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    Review of income and wealth 20 (1974), S. 0 
    ISSN: 1475-4991
    Source: Blackwell Publishing Journal Backfiles 1879-2005
    Topics: Economics
    Notes: The reliability of the quarterly national income and product (NIP) accounts of the United States is examined from several standpoints. First, possible sources of error in the quarterly NIP accounts are explored, the most important being the lack of appropriate data, seasonal adjustment errors, sampling errors and biases, and the nature of the U.S. statistical system. Next, four ways of assessing the reliability of the accounts are considered. The most weight is given to measures of revisions in early estimates of the quarterly NIP aggregates. Results of previous studies of revisions are reviewed, and a summary of a major study of revisions for the period 1947–71 is given. The other ways of assessing reliability which are examined are the effect of errors on economic policy making, analysis of the statistical discrepancy, and expert judgment on sources and methodology.The degree of accuracy is judged to be generally sufficient for the policy decisions for which the NIP estimates are used. The early estimates of a quarter's change in GNP almost always distinguish whether the ultimate estimate will be large or small and will usually distinguish whether the ultimate estimate will be larger or smaller than the preceding quarter. While the accuracy of the estimates has generally been sufficient, the accuracy for 1965 was judged insufficient by policymakers. There is some evidence that errors have been reduced over time.
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  • 26
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    Review of income and wealth 20 (1974), S. 0 
    ISSN: 1475-4991
    Source: Blackwell Publishing Journal Backfiles 1879-2005
    Topics: Economics
    Notes: Most developing countries have compiled national accounts on a regular basis only for the last few years. It has not yet been possible for them to collect many of the statistics necessary to obtain good coverage of their economic activities by methods which would generally be accepted as reliable. Consequently the checks on reliability imposed by the framework of the national accounts are often absent, and the accounts prepared contain many estimates of doubtful quality. These doubts can usually only be removed as statistics collected by better methods become available. This is proving to be a slow process, partly because of the shortage of trained statistical staff and the competing demands of social and demographic statistics and partly because of the inherent difficulties in collecting good statistics from small businesses and traditional households. The need to define traditional households as producers as well as consumers leads to our demanding extra information from this difficult sector. In addition it is often difficult for the national accounts statistician, and even more so for the user, to find out in the time available exactly how some of the statistics with which he is presented were obtained. When this cannot be done it is impossible to assess their reliability. Thus assessing the overall reliability of national accounts in developing countries for even a limited range of uses is at present largely a matter of personal judgment. The information necessary to make more objective assessments rarely exists and hence the problems which developed countries face in using such information are not yet within the experience of most developing countries.
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  • 27
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    Review of income and wealth 20 (1974), S. 0 
    ISSN: 1475-4991
    Source: Blackwell Publishing Journal Backfiles 1879-2005
    Topics: Economics
    Notes: This paper examines the wealth position of blacks relative to whites, on the basis of data in the Survey of Economic Opportunity. The analysis indicates that at the same levels of both income and wealth blacks consistently invest more in consumer durables, especially housing, than do whites. The paper then explores possible explanations for this finding, suggesting that these investment differences are not solely due to the income and wealth position of blacks, but may be due to a smaller set of investment opportunities institutionally fostered by discriminatory forces.
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    Review of income and wealth 20 (1974), S. 0 
    ISSN: 1475-4991
    Source: Blackwell Publishing Journal Backfiles 1879-2005
    Topics: Economics
    Notes: The author attributes economic growth in Hungary to three factors: structural change, increase of employment, and productivity. On the basis of this he points out that in the 1950's the first two factors were responsible for nearly half of the economic growth. From the 1960's this tendency has changed; more and more importance has been taken by the increase of productivity. As the main source of economic growth is the increase of industrial productivity, in the further part of the study the author makes an attempt to break down the development of Hungarian industry into its components and to analyse their efficiency. Starting from the present conditions of industrial development he investigates what further increase of industry the resources accumulated till now and their probable growth will allow in the future.Taking into account the role of material and human resources the author draws the following conclusions.Industrial production will increase in the future at the same rate as productivity.The increase of industrial investment will probably be lessened, which postulates the greater increase of capital productivity as well as that productivity will increase at a higher rate than the capital-labour ratio.These conclusions assume an increase in the efficiency of industrial investment and an above average increase in the high-productivity branches.A further source of increasing productivity is accumulated human capital. The higher educational level is one of the guarantees for the ever-increasing role of productivity in economic growth in the future.
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  • 29
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    Review of income and wealth 20 (1974), S. 0 
    ISSN: 1475-4991
    Source: Blackwell Publishing Journal Backfiles 1879-2005
    Topics: Economics
    Notes: This paper compares preliminary estimates (available about four months after the close of the period to which they refer) with final estimates (available three years after the close of the period) for certain national accounting aggregates and some of their major components. It concludes that preliminary estimates are consistently low for gross domestic product, exports, and public consumption, whereas imports, private consumption, and gross capital formation may be either low or high. The best early estimates, in the sense of closest to the final figures, are those for gross domestic product, imports, and exports.
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    Review of income and wealth 20 (1974), S. 0 
    ISSN: 1475-4991
    Source: Blackwell Publishing Journal Backfiles 1879-2005
    Topics: Economics
    Notes: Economic realities can be described in national accounting only by certain approximative means and presumptions; therefore they cannot be measured with absolute accuracy. However, because of their great importance these investigations must fulfil as far as possible the reliability required for the economic control and planning of the national economy, in accordance with predetermined concepts and methods.The reliability of national accounting is favourable in Hungary, as they are based mostly (92 percent) on the bookkeeping data of enterprises, cooperatives and institutions. The bookkeeping system is uniform in all economic organizations, in conformity with central regulations, and it takes into account the demand of computations for national accounting.Despite these favourable conditions lesser or greater contradictions can be found in the national accounts every year. The absolute measure of the differences is not significant; however, if compared to the annual increase it results in uncertainty of 15 percent. The uncertainty is reduced by the fact that the sign of differences is the same every year.The author classifies the causes of uncertainty in national accounts into four groups: 1. problems of the time shift of the connected economic processes and of their accounting; 2. effect of the enterprise interests; 3. inadequacy of methodological regulation; 4. inaccuracy of data surveys and processing. The study deals with the special factors of inaccuracy occurring in constant price accounting. Inaccuracy of the most important aggregates, for instance that of the volume index of the national income, comes to 0.5-0.7 percent which results, in the case of a yearly 5 percent “real” increase in the index, in reliability limits of 10 to 15 percent.In the concluding part of the study the author points out that in Hungary the unexplored contradictions are not shown as “statistical discrepancy” but they are included in the various aggregates on the basis of considerations discussed in the study.
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    Review of income and wealth 20 (1974), S. 0 
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    Review of income and wealth 20 (1974), S. 0 
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    Topics: Economics
    Notes: Defining investment as outlays that increase income- and output-producing capacity, the author presents estimates of human investment in the United States 1929–69, comprising rearing costs, education, training, health, safety and mobility outlays. He develops an economic accounting framework to accommodate human investments and research and development in national and sector capital accounts, with appropriate adjustments to the current accounts to provide consistency. The associated balance sheets and wealth statements are also developed.The wealth and corresponding income estimates are used to compute rates of return on human, non-human, and total capital. In the business economy the average net rate of return on total capital was 10.6 percent in 1969, compared with 10.0 percent in 1929. The average and marginal rates of return on human capital were generally somewhat higher than on non-human capital throughout the period.
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    Review of income and wealth 20 (1974), S. 0 
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    Topics: Economics
    Notes: Radical changes, up and down, have taken place in the estimates of growth in total factor productivity in the U.S. made by different economists, or by the same economists at different times. If such estimates provide “some sort of measure of our ignorance,” as Abramovitz once put it, we seemed to be a lot less ignorant in 1927 (when Cobb and Douglas published their famous paper), or in 1967 (when Jorgenson and Griliches published theirs), than we were in the years between (when Schmookler, Abramovitz, Kendrick, and Denison completed their studies), or than we are today (when we have, or will soon have, revised estimates by Denison and by Kendrick, and new estimates by Christensen and Jorgenson). Viewed in this perspective, many questions may be raised about the significance of the current estimates that something like a third or more of the rate of increase in U.S. national output is “due” to increase in productivity, as well as about the concepts, data, and methods that underlie the estimates. A list of particular subjects worth considering for research is given and each is briefly discussed.
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    Review of income and wealth 20 (1974), S. 0 
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    Topics: Economics
    Notes: This paper examines the available evidence relative to the distribution of income in a developing country, Colombia, over a relatively long span of years, roughly from the mid-30s to the mid-60s, especially in the context of the argument that recent growth has been characterized by worsening distribution and stable or declining incomes for lower income groups. The basic conclusions are that income distribution within agriculture worsened throughout the period, while non-agricultural income probably worsened from the mid-30s to the early 50s, improved from then to the mid-60s, and then leveled off. During the period of improvement in non-agricultural income, it appears that the overall distribution also improved somewhat. Over the period as a whole, the main gainers have been the second and third deciles from the top; the top decile appears to have lost. The bottom two deciles also appear to have lost.
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    Topics: Economics
    Notes: This paper examines two different approaches to the estimation of the size distribution of wealth. The first section describes new estimates for the distribution in Britain in 1968 using the estate method and discusses the sensitivity of the results to the main assumptions. The second section presents preliminary estimates using the investment data, a method which has not been widely used. In the final section the results obtained for the upper tail of the distribution from the two methods are compared.
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    Geophysical prospecting 22 (1974), S. 0 
    ISSN: 1365-2478
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    Topics: Geosciences , Physics
    Notes: For horizontal layering and plane horizontal impulsive wavefronts it is theoretically possible to get rid of multiple reflections by a feedback procedure which can easily be derived using raypath philosophy. To reduce the increase of noise inherent in the method the precise theoretical formulae are altered in such a manner that a practical application becomes possible. For this purpose the autocorrelation will be used.Application of the new process to a CRP section where the shot geophone distances in the field had not been long enough to attenuate multiple reflections effectively gave favourable results.
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    Geophysical prospecting 22 (1974), S. 0 
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    Topics: Geosciences , Physics
    Notes: Two in situ measurements of stress wave velocity in a granodiorite massif were made. Firstly, the velocities close to the source were investigated (for elimination of the influence of cracks), and secondly, the velocities in different horizontal directions over a large area were studied from the viewpoint of their dependence on the crack system of the medium. A correlation between the mutual orientation of the cracks and the maximum or minimum values of the stress wave velocities was obtained.
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    Geophysical prospecting 22 (1974), S. 0 
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    Topics: Geosciences , Physics
    Notes: The technique of linear digital filtering as developed for the direct interpretation of Schlumberger and Wenner soundings (Ghosh 1971) has been applied here for the derivation of the resistivity transform function from the field dipole measurements as the first step in directly interpreting dipole data. Filter coefficients for this transformation have been worked out for the radial-polar, perpendicular and parallel (30°) arrays of dipole sounding. The procedure combines speed with accuracy.
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    Topics: Geosciences , Physics
    Notes: Dipole soundings are more sensitive to noise caused by lateral and superficial inhomogeneities than Schlumberger soundings. However, the former are preferable for deep explorations in view of the relatively short cables required. The simple solution of carrying out the field work by means of dipole spreads, and to transform the dipole resistivity diagrams into Schlumberger ones by means of proper formulae would be valid only for smooth and regular curves; but often, owing to the presence of lateral noises, the dipole data show a considerable scatter. For such cases a “continuous dipole sounding” method is proposed for which all successive dipoles are contiguous, so that all parts of the profiles are covered and interpolation is not necessary. Obviously the moving dipoles have lengths proportional to their distances, so that they appear equal in the usual bilogarithmic scale. It follows that only polar-dipole arrays may be used. The transition from a dipole to the corresponding Schlumberger apparent resistivity diagram requires an integration constant which is not unequivocally determined. Therefore, the solution is not unique, but all possible derived Schlumberger diagrams have a common part. Similarly, they have some common interpretative results, which may be referred to the original dipole diagram obtained in the field.A special measurement technique is required since the dipole-dipole voltages to be determined are noticeably smaller than the Schlumberger ones. This is true also because dipole soundings are used for great depths and for long distances between the two dipoles.
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    Geophysical prospecting 22 (1974), S. 0 
    ISSN: 1365-2478
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    Topics: Geosciences , Physics
    Notes: Basic requirements for a seismic reflection system using a moderate-power controlled source are discussed. General considerations and computer modelling show promise for geophysical prospecting, especially at low penetration and very high noise level. For many applications, ranging from mineral and water prospecting, to civil and military engineering, and even archeology, a relatively cheap, small and portable device of this kind might be more convenient than conventional explosive sources or sophisticated controlled sources of the vibroseis type. The use of a simple, low frequency periodic signal facilitates rapid data processing procedures and suggests that the mechanical generator will be very simple and cheap.
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    Geophysical prospecting 22 (1974), S. 0 
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    Topics: Geosciences , Physics
    Notes: A method is described to transform a dipole sounding curve, obtained with any one of the common dipole arrays over a horizontally layered earth, to the form of a Schlumberger sounding curve. Starting from the general expression which relates the dipole apparent resistivity to the Schlumberger apparent resistivity and its derivative with respect to the spacing, it is possible with some approximations to derive an easy numerical computation procedure in order to perform the transformation. The applicability of the method is discussed briefly.
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    Geophysical prospecting 22 (1974), S. 0 
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    Topics: Geosciences , Physics
    Notes: Approximate deconvolution by means of Wiener filters has become standard practice in seismic data-processing. It is well-known that addition of a certain percentage of noise energy to the autocorrelation of the signal wavelet leads to a filter that does not increase, or even reduces, the noise level on the seismogram. This noise addition will, in general, cause a minimum phase signal to become mixed phase. A technique is presented for the calculation of the optimum-lag shaping filter for a contaminated signal wavelet. The advantages of this method over the more conventional approach are that it needs less arithmetic operations and that it automatically gives the filter with the optimum combination of shaping performance and noise reduction.
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    Notes: A set of parabolae is defined to approximate the observed gravity profile for specifying the lateral density variation in a two dimensional causative body. This variation separates the “biased” as well as “unbiased” residual anomaly structure. The method may be directly incorporated into existing numerical and graphical techniques of interpretation for subsequent delineation of structural configuration. The simple relations derived by inspection of the observed gravity profile permit universal application of the technique and in particular for the determination of the size and shape of sub-shelf structures. The suitability of the method in various problems of two dimensional interpretation has been indicated through an illustration of the Godavari Basin (India).
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    Geophysical prospecting 22 (1974), S. 0 
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    Topics: Geosciences , Physics
    Notes: Decomposition of IP discharge curve into a sum of exponentials yields more information than present practice does. Such a work was performed, as a beginning, by hand, plotting the ordinates on semi logarithimic paper. It gave, according to the cases, two or three exponentials, each with an amplitude Ai and the time constant τi.Three examples of ground prospection are given, the third of which shows an anomaly, unnoticed with present technique but obvious on a profile curve with A1/A2 in ordinates.A computer processing technique is described which yields directly the time constants τi by seeking a differential equation which the IP voltage satisfies; the order of the equation is set arbitrarily. On a practical prospection record with only two exponentials, the assumption that the differential equation does not depend on charge duration (everything else being equal) has been checked (the shape of the curves would depend on boundary conditions). The assumption roughly holds for charge durations from 5 seconds to 40 seconds. We hope that a larger number of exponentials will yield better results.〈section xml:id="abs1-2"〉〈title type="main"〉SommaireLa décomposition de la courbe de décharge en une somme d'exponentielles permet d'en tirer plus d'information que la pratique actuelle. Un tel travail a été fait, pour commencer, à la main en portant les ordonnées sur papier logarithmique; il a fourni, suivant les cas, deux ou trois exponentielles avec, pour chacune d'elles, le coefficient Ai et la constante de temps τi.On donne trois exemples de prospection sur le terrain, dont le dernier comporte une anomalie, inaperçue avec la technique actuelle, mais bien mise en évidence en traçant la courbe de A1/A2 le long du profil.On donne ensuite une technique de calcul sur ordinateur des τi, en recherchant l'équation différentielle à laquelle obéit la tension ΔVPP enregistrée, l'ordre de cette équation étant fixé arbitrairement. On a cherchéà vérifier sur un enregistrement de terrain, avec. deux exponentielles seulement, l'hypothèse suivant laquelle l'équation différentielle ne dépend pas de la durée de charge (toutes choses égales d'ailleurs). L'hypothèse se trouve grossièrement vérifiée pour les durées de charge allant de 5 secondes à 40 secondes, et nous espérons qu'un plus grand nombre d'exponentielles donnera de meilleurs résultats.
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    Geophysical prospecting 22 (1974), S. 0 
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    Topics: Geosciences , Physics
    Notes: The conventional seismic technique is subject to a recording time following each transmission of energy, in which it is forbidden to release any new pulse. The recording time depends on the deepest reflection of interest, and is often 10 seconds or more in actual practice. To each transmission corresponds one record, i.e. a fixed amount of data which cannot be increased in a given time.Pulse coding allows us to go beyond this limit, by transmitting several times during the normal recording time. The procedure gives as many records as there are pulses, but they overlap, each event being repeated every time there is a pulse. It is possible to process the composite record back to its usual appearance with all events in their proper place if the time breaks are accurately known and make up a code such that the unavoidable noise generated by the process be kept, on the final section, below the ambient noise. The processing is quite similar to that of records made from vibrating sources, though faster in practice.The additional information can be devoted to a saving of time and money as the same profile may be recorded in a shorter time; or to an improvement of quality of the section due to a higher order of coverage, a multiplication of the ray paths and a closer sampling of the reflectors. It is also possible to record information in several planes at the same time, and to work out a 3-dimensional restitution, without loss of production.The process applies to all kinds of sources provided they can be triggered according to the code with sufficient accuracy. Depending on the source and conditions of implementation, the method benefits from other advantages such as better resolution, increased flexibility, and better coupling.Two different names have been given to the process, Sosie and Seiscode, which apply to slightly different parameters for the sequence of pulses. Sosie is more useful at sea, while the normal scope for Seiscode is onshore. Both names are trademarks for SNPA.
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    Topics: Geosciences , Physics
    Notes: Two-layer type curves of apparent frequency effect for the Wenner configuration are presented. The formulation is based on the normal definition of frequency effect in terms of resistivities measured at different frequencies plus the definition of apparent resistivity over two horizontal layers as a function of first and second layer resistivities. The use of these type curves in the interpretation of multilayer apparent frequency-effect curves is described and some field examples are given.
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    Topics: Geosciences , Physics
    Notes: In this paper properties of the discrete zero-phase time function are derived and compared with related properties of the discrete minimum-phase time function.The two-sided minimum-length signal is introduced and it is derived that, for any given amplitude spectrum, the two-sided minimum-length signal and the signal with zero-phase spectrum are identical signals. A comparison is made between the one-sided minimum-length signal (minimum-phase signal) and the two-sided minimum-length signal (zero-phase signal).A computational scheme is discussed which determines the zero-phase correspondent of a given signal.A method is proposed to compute zero-phase least-square inverse filters. The efficiency of minimum-phase and zero-phase least-square inverse filters is shown on signals with different phase properties.A criterion is derived which determines whether a symmetric time function has the zero-phase property. The close relationship with the minimum-phase criterion is discussed.Finally the relationship between signal length and resolving power is illustrated on numerical examples.
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    Notes: Empirical equalities derived from time domain induced polarization scale modelling with the gradient array over simple geometries, and from the potential field functions for equivalent simple charge configurations are similar. The function for the dyke like body is analogous to the magnetic case allowing both total and vertical magnetic field interpretation techniques to be applied to gradient array chargeability anomalies.
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    Notes: A checking method of digital multiple elimination and of deconvolution processing using computers and based on optical autocorrelation is first presented. Comparison between autocorrelograms before and after a single or several processing steps allows to estimate, on one hand, the strength of the deconvolution obtained, known by the study of the central parts which is in fact the signal autocorrelation, on the other hand, the multiple elimination given by the study of side parts of the autocorrelogram.Further, an optical deconvolution procedure, is presented. For this, it is supposed that the signal is known and optically reproduced in the same way as the one of a trace. This is achieved by sphero-cylindrical optics allowing trace to trace processing. Deconvolution is carried out in the spectral domain by inserting a filter in the Fourier plane of the optical unit, the transmission law of which expresses the Fourier transform of the antisignal. This filter device introduces a holographic technique called Fourier holography, in such a way phases as well as amplitudes are preserved.Several results are presented from a synthetic section and also from field sections.
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    Notes: The separation of regional from local gravity anomalies by means of the application of two-dimensional linear filters is analyzed. It was found that optimization of the filter in the least squares sense leads to filters that produce strong localized concentrations of the error, which may erroneously be interpreted as anomalies. For this reason the maximum absolute value of the error is a more important criterion for the quality of the filter than the root mean square error. This maximum absolute error is minimized by the minimax filter. Intermediate filters are derived which give a transition zone which comes appreciably closer to that of the optimal filter at only a small price in terms of increase of the maximum absolute error.
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    Notes: Cable feathering is defined as the angle between a line connecting the cable end points and the line of the seismic profile. It is shown that an average reflection point map is more accurate than a shot point location map for geologic interpretation. Geologic resolution is degraded by feathering and this degradation is a function of the number of channels recorded. Feathering in areas of dipping reflectors produces non-standard normal move-out because the depth points are not common, and the perpendicular distances to the reflecting surfaces vary among traces in the c.d.p. gather. An example of a profile shot across a large river is discussed.
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    Notes: First, we review briefly the principle of the method, the computation of theoretical curves for a layered earth, and the recording technique in use in our surveys.The case history deals with an area covered with overthrust nappes (marls of Miocene age), which had slid on a Triassic sole, obscuring the geological picture.The magnetotelluric survey followed those of gravity and aeromagnetics and preceded the seismic one from North to South, it displayed a shallow and gently dipping basin, a major fault system, and a deep basin with a thick resistive layer, often underlying a conducting one.The seismics, and later the drilling of a well East of the profile, confirmed these features; in particular, the thick resistive layer was revealed to be Jurassic; only its thickness had been slightly overestimated. This fact lead the people in charge of the operations to ask for a reinterpretation synthesis of magnetotellurics, seismics and gravity, the results of which are also presented.
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    Grass and forage science 29 (1974), S. 0 
    ISSN: 1365-2494
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    Topics: Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition
    Notes: Elimination of shooly larvae increased grass yields daring the September feeding period. Increases were usually less than 10% bat in one case, where growth was abnormally slow, die increase was over 30% and in another, where the larval population was atypically dense, it was almost 60%. The effects of damage were not cumulative daring the feeding period; and at the end of this period insecticidreated plots sometimes gave lower yields than untreated plots. Fertilizer increases had a much greater effect on yield than did control of larvae and, where N was applied at 75 kg/ha (67 lb/ac) in spring, the additional effect of larval control was usually negligible. It is suggested that shoot-fly damage may be more serious in other localities.When turf containing shoot-fly larvae was ploughed, Oscinella spp. re-established themselves more successfully than others in seedling ryegrass bat did not damage the new sward appreciably.
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    Topics: Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition
    Notes: The drying of small herbage samples should be as rapid as possible so as to limit respiratory loss and enzymatic interconversions, especially if certain nonstnictnral carbohydrates are to be assayed. An inexpensive thermo-switch is described that indicates the time required to heat a mass of tissue in an oven to a given temperature. The time required to heat green herbage to a temperature (55°C) that will inactivate respiratory enzymes can be determined.
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    Topics: Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition
    Notes: A linear programming model of a high-temperature grass-drying enterprise is described. From information about seasonal crop response, area of crop available and management constraints, the model determines the harvesting schedules which give greatest returns, less costs, from the enterprise over the season. This information can be used to examine the effects of long-term strategic decisions or to evaluate economically data on new crops from field experiments. For example, assuming a fixed cost of λ70,000/year for a high-temperature grass-drying installation and what is considered to be reliable input data for 1972, the returns less costs for optimum harvest schedules from different areas or crop varieties are:〈table colsep="0" rowsep="0" frame="topbot" pgwide="1" orient="port"〉〈tgroup cols="5" align="left"〉〈colspec colnum="1" colname="col1" align="center"/〉〈colspec colnum="2" colname="col2" align="center"/〉〈colspec colnum="3" colname="col3" align="center"/〉〈colspec colnum="4" colname="col4" align="center"/〉〈colspec colnum="5" colname="col5" align="center"/〉〈thead valign="bottom"〉〈entry namest="col1" nameend="col2" align="left"〉Corp areaSurplusGrass ac (ha)Lucerne ac (ha)Return, £Less costs £/ac(£/ha)crop ac (ha)〈tbody valign="top"〉800(324)0(0)42,849536(132.3)0(0)1000(405)0(0)60,286603(1489)205(83)600(243)200(81)46,73158.4(1442)0(0)800(324)200(81)65.66165.7(1621)109(44) The model can also provide information con cerning tbe limitations imposed by equipment stage of tbe process and management re straints sucb as limitations on overtime and shut downs for holidays or maintenance.
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    Grass and forage science 29 (1974), S. 0 
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    Source: Blackwell Publishing Journal Backfiles 1879-2005
    Topics: Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition
    Notes: Newly-sown S24 perennial ryegrass at Hurley and old established ryegrass-dominant mixed pasture at Rothamsted were treated with several pesticides, singly and in combination, over the period 1969–73. Yields were either unaffected or increased by up to 30% in any one year, depending on the treatment, the newly-sown sward giving the more consistent response from year to year.
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    Grass and forage science 29 (1974), S. 0 
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    Source: Blackwell Publishing Journal Backfiles 1879-2005
    Topics: Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition
    Notes: The DM production from INRA 200, an early maturing hybrid maize grown for silage, was 10±6 and 14 5 t/ha in mid-October 1972 and 1973 (4±2 and 5±8 tons/ac). The plant population in both years was approximately 112,000/ha (45,320/ac). Whole-crop and cob DM percentages were 18±2 and 21±3 for 1972 and 39±9 and 53±0 for 1973, respectively. The cob yields were 49 and 10±4 t/ha (2±0 and 4±1 tons/ac) in 1972 and 1973 and cob in the two years accounted for 46 and 72% of total yield. At harvest the 1973 crop was 4–6 weeks more mature than the 1972 crop. These differences were attributed to the difference in accumulated temperature recorded from May till October, which was 567°C days in 1972 and 817 in 1973. Whole-crop DM content, yield of cob and yield of cob as a percentage of total yield were studied against seasonal temperature accumulation. In the case of DM percentage there was a highly significant linear regression which showed that 627°C days were needed to mature maize to 24% DM content.
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    Grass and forage science 29 (1974), S. 0 
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    Source: Blackwell Publishing Journal Backfiles 1879-2005
    Topics: Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition
    Notes: Experiments were carried out with different depths of added topsoil, with different methods of cultivation and with different rates of application of fertilizers on an ash disposal site near Newark. Good yields of hay and wheat were obtained and were shown to vary systematically with the treatment of the plots. Good yields of wheat were obtained with a top dressing of 125 kg N/ha even on bare ash but, in contrast with the yields of DM from grass, yields of grain tended to increase with increasing depth of added soil. This pattern appeared to be influenced by the variations in spring rainfall. There appeared to be no adverse effects of uptake of trace elements from the ash.
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    Grass and forage science 29 (1974), S. 0 
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    Source: Blackwell Publishing Journal Backfiles 1879-2005
    Topics: Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition
    Notes: The DM and N contribution of S184 white clover in mixed ryegrass/clover swards was recorded at Pant-y-dwr Hill Centre (305 m) for 4 years, 1967–70. By direct comparison with fertilized grass swards it was estimated that the clover N contribution on peaty gley soil averaged 100 kg N/ha per year (89 Ib N/ac) under cutting and 98 kg N/ha (87 ib/ac) under grazing with faecal return. On more fertile acid brown earth the corresponding contributions were 81 and 90 kg N/ha (72 and 80 Ib/ac). Full replacement of clover by N fertilizer would require average annual applications of 268, 229, 156 and 128 kg fertilizer N/ha, respectively (239, 204, 139 and 114 Ib N/ac).
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    Grass and forage science 29 (1974), S. 0 
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    Topics: Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition
    Notes: Book reviewed in this article:EYRE, S. R. (Editor) World vegetation types.SCHMIDT, W.; WETTERAU, H.; BEYRICH, H.; MÜLLER, M.; GOTTSCHLING, E.-M. [Silage production.] Silageherstellung.LAMBRECHTSEN, N. C. What grass is that? A guide to identification of some introduced grasses in New Zealand by vegetative characters.LEIGH, J. H.; NOBLE, J. C. (Editors) Plants for sheep in Australia.THURM, R. [Technology of agricultural production.] Technologie der landwirtschaftlichen Produktion.TAYLOR, S. A.; ASHCROFT, G. L. Physical edaphology. The physics of irrigated and nonirrigated soils.DAVIES, D. B.; EAGLE, D. J.; FINNEY, J. B. Soil management. Ipswich, Suffolk, UK, Farming Press Limited.OLSON, R. A.; ARMY, T. J.; HANWAY, J. J.; KILMER, V. J. (Editors) Fertilizer technology & use.PAPADAKIS, J. Auxins, biochemical plant interaction, growth retardants and dense high yielding crops. Córdoba, Argentina, J. Papadakis.
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    Topics: Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition
    Notes: An electronic pasture-meter was found to be of limited use for the routine estimation of DM production of oat cultivars for the reason that the relationship between the meter reading and DM varied with different cultivars.
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    Grass and forage science 29 (1974), S. 0 
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    Source: Blackwell Publishing Journal Backfiles 1879-2005
    Topics: Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition
    Notes: The duration of the juvenile phase in early-flowering (Dorset Marl) and late-flowering (S123) red clover is described. Neither cultivar responded to inductive conditions at the first leaf stage but Dorset Marl attained maximum sensitivity by the 3-leaf stage. A comparable response was obtained with S123 only after the production of 12–13 leaves. The growth characteristics of the two types under continuous long or short days are described and possible explanations are advanced for the characteristic differences in tillering and stem internode number.
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    Grass and forage science 29 (1974), S. 0 
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    Source: Blackwell Publishing Journal Backfiles 1879-2005
    Topics: Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition
    Notes: For three weeks after emergence, micro-swards of Lolium rigidum were defoliated to a height and at a frequency which represented a range of set stocking rates of less than, similar to, and more than 7–8 sheep/ha as based on the results of Greenwood and Arnold (6) and referred to as D1, D2 and D3 respectively. The effects of these defoliation regimes on the growth and development of emergent swards were evaluated according to their effect on increments of DM from plant parts, rate of appearance of leaves and tillers, concentration of soluble carbohydrates, and on the uptake and concentration of inorganic nutrients.Defoliation began five days after emergence, when the dry weight of the shoot was 3g/m2. After 20 days of treatment, 6±7 g/m2 of DM had been removed from D1, 5±5 g/m2 from D2 and 51 g/m2 from D3; and the dry weight of shoot remaining was 13, 7 and 4±5 g/m2 on D1, D2 and D3 respectively. The effect of defoliation on dry weight of plant parts increased in severity in the order leaf 1, stem+sheaths, leaf 2, roots, leaf 3, tiller 1, tiller 2, leaf 4. Average relative growth rate of the sward was reduced from 17% per day on D1 to 13% per day on D3. There was no necrosis of root tissue. Emergence of the later leaves and of the tillers was retarded by up to three days by more frequent defoliation. Alcohol-soluble carbohydrates in the root fell from over 6% to about 1±5% on all treatments. Uptake of N. P and K was limited by increasing intensity of defoliation and because concentrations of those elements were not greatly affected, the limitation could be ascribed mainly to the effects of defoliation on plant size.The plausibility of the technique for the experimental simulation of grazing of emergent annual grass swards in Western Australia is discussed. It is concluded that for set-stocking rates of less than about 12 sheep/ha, grazing, while reducing DM production just after emergence, is unlikely to produce severe physiological stresses in the sward.
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    Topics: Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition
    Notes: The uptake of N was measured in 2 successive regrowths harvested on 12 June and 13 Aug. following harvests of primary growths 8, 12, 16, 23, 29, 45 and 57 (12 June) days after applying N at 59, 118 or 177 kg N/ha on 16 Apr.Residual responses were obtained to both increments of N, leading to high apparent recoveries of fertilizer N, especially to the higher increment. This increased availability of soil N when high rates of N are applied is shown to vary with date of harvest of primary growth, reaching a maximum equivalent to 151% apparent fertilizer N recovery 23 days after N application.In the second regrowth, percentage N in the herbage showed a negative response to N applied to the primary growth. This appears to reflect a reduction in available soil N brought about by its increased availability and uptake in primary growth and first regrowth.The possibilities of improving the efficiency of fertilizer N by exploiting soil N are considered against the possible reduction in available N for future regrowths.
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    Topics: Geosciences , Physics
    Notes: Qureshi and Mula have suggested a computer method for the calculation of the shape of a two dimensional body from the gravity anomaly profile associated with it. The application of the method, however, was restricted to those bodies which have their top or base horizontal and end sides vertical. In this paper study has been made to investigate the possibility of eliminating the above mentioned restrictions and has arrived at the affirmative conclusion.
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    Topics: Geosciences , Physics
    Notes: Consideration is given to the form of apparent resistivity sections obtained by varying electrode array position and spacing over two dimensional features.Since basic solutions exist for horizontally layered media and for vertical or dipping single interfaces, simple rules are proposed whereby these solutions can be directly combined to give solutions for more complex sections. Substantial approximations may be involved as the rules do not fully allow for interactions between the constituents.The range of error incurred in application of the rules is explored, with particular reference to the square array system of resistivity measurement. The two extremes- of orientation of the square array with respect to the line of section are separately considered in this survey.Within appropriate limits, the rules appear extendable to a wide variety of simple structures for which rigorous solutions would be formidable. The rules are finally discussed in relation to practical applications.
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    Topics: Geosciences , Physics
    Notes: In modern oil exploration layers of prospective interest with rather simple structural features are often overlain by very complicated bodies as e.g. saltdomes or other kinds of diapirs, olistostromes, or front zones of overthrusted blankets. In all these cases normal reflection seismic investigations, where downgoing and upgoing rays are rather close to each other, mostly fail, either because no reflections from underneath the complicated bodies are obtained, or because a reliable migrated depth presentation becomes practically impossible due to the inhomogeneity of the overlying bodies.The undershooting technique avoids these difficulties by using ray paths which do not traverse the complicated bodies e.g. by shooting on one side of a saltdome and recording on the other side. On account of the large shot-geophone distances in this method special considerations and computer processes were developed concerning moveout corrections for common depth point stacking and migrated depth presentation.In many cases the location of the disturbing complicated bodies is known in advance. The shooting and recording program can then be adjusted to this knowledge and thereby kept to a minimum. If the location of the complicated bodies is unknown a more extended seismic program has to be carried out encompassing a great variety of shot-geophone distances. But in this case the approximate location of the complicated bodies can be deduced from the survey too.Results are presented in order to give an idea of the efficiency of the new seismic tool.
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    Topics: Geosciences , Physics
    Notes: This paper describes the procedure for interpreting the apparent resistivity data measured with the two-electrode array directly with the help of kernel function. The calculation of kernel function from the observed resistivity curve is done by the method of decomposition. In the method of decomposition the resistivity curve is approximated by a sum of certain functions, whose choice is only restricted by the requirement that the contribution to the kernel function corresponding to them should be easily computable. A few such functions are classified. These, and the standard curves for corresponding kernel functions obtained by utilising an integral expression for two-electrode array expressing the kernel explicitly in terms of the apparent resistivity functions, are plotted on log-log scale. The determination of layer parameters, that is, the layer resistivities and thicknesses from the kernel function can be carried out by a method proposed by Pekeris (1940).
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    Topics: Geosciences , Physics
    Notes: A six-channel wide-band digital system for magnetotelluric measurements is described The system is designed to operate in the frequency band 10-.0001 Hz. The recording is made on a 7 track tape in an IBM compatible 12 bit format. The amplitude and phase responses of the system and sample records are presented.
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    Notes: Several types of multichannel filters have been introduced in the past with the purpose of rejecting, in a seismic section, coherent noise having a slope different from that of the signal.These filters, generally, tend to introduce a certain amount of mixing and therefore the output trace shows increased horizontal coherence. This is due to the model on which these filters are based, since the hypothesis is posed that the reflectors are continuous. This may be dangerous since it could lead to mistaken interpretations, for example when small faults or breaks are made to disappear in the output section.Other problems that could arise in the application of multichannel filters after-stack are space-aliasing and high-pass filtering. The former occurs when coherent noise is rejected with apparent Velocity V and frequency fa=V/X, where X is the distance between traces. In this case, the signal also is distorted since it is rejected in the same frequency range. The high pass filtering effect occurs when the multichannel filter is designed to remove low coherent noise with high apparent velocity.In the paper a family of multichannel filters is presented based on a model of the seismic section such that minimum mixing effects appear. The filters are designed to give good results even in the case of low frequency and high velocity coherent noise.Some practical examples are shown.
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    Grass and forage science 29 (1974), S. 0 
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    Topics: Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition
    Notes: In the management of British grassland lay there appears to be a marked divergence between the policies advocated by grassland science and general grassland practice. While science places emphasis on monocultures of sown species (mainly perennial ryegrass), heavily fertilized and intensively stocked, grassland farmers for the most part rely on lonstablished or indigenous swards composed of a variety of species and receiving modest applications of fertilizer. Since the gap between the two approaches is both substantial and of long duration the subject appears to be worth fresh attention. The purpose of this paper is to examine the current situation in relation to improvement in botanical composition and to suggest new approaches to that end.
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    Topics: Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition
    Notes: The last 10 years have seen a marked shift in Britain from the growing of legumes towards the use of fertilizer N. Many farmers are now reassessing the position Decause of increasing fertilizer prices and because of improvements in clovers and lucerne through plant breeding.On the intensive dairy farm legumes can play an important part in the conseravation block. The yield of lucerne without applied N is as high as from ryegrass with 250 units N/ac. Red clover is also useful over a wide range of soil types.On the less intensive farm, white clover should be contributing throughout the grazing area. there are many reasons for poor white clover populations in pastures; one of these is the fungus disease Sclerotinia trifoliorum, commonly known as clover rot. Varieties resistant to this disease are available in both red and white-clover. Verticillium wilt in lucerne bas also been checked by the plant breeder.Improved legume varieties justify a completely new look at these crops and the possibilities for lucerne in this country appear to be particularly good.
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    Topics: Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition
    Notes: Irrigated plots of a mixed sward of Lolium perenne, Paspalum dilatatum, Bromus unioloides, Dactylis glomerata and Trifolium repens were used in 2 experiments during 4 years. In the first experiment, die treatments comprised factorial combinations of heights of cutting of 3, 6 and 10 cm (1.2, 2.4 and 3.9 in.) above ground level, and heights of growth of 5, 13 and 20 cm (20, 5.1 and 8.0 in.) above the height of cutting. In the second experiment, 8 combinations of dose (3 cm or 1.2 in.) or lax (10 cm or 3.9 in.) cutting were applied at various times during each year.In the first experiment, DM production for cutting heights of 3, 6 and 10 cm was 50, 44 and 43 t/ha (198,17.5 and 171 ton/ac), respectively; the DOM production was 37, 32 and 32 t/ha (147, 12.7 and 12.7 ton/ac). DM production for growth heights of 5, 13 and 20 cm was 45, 46 and 48 t/ha (17.9, 183 and 191 ton/ac), respectively. DOM production, 34 t/ha (13.5 ton/ac), was not affected by height of growth.Percentages of protein (26, 22 and 20) and DOM (76, 72 and 71) declined as the height of growth was increased; but cutting height produced no significant effects in them. As cutting height was increased the percentage of clover declined (40, 31 and 23) and that of grasses increased (52, 66 and 72); diere were smaller changes with changes in height of growth.Hie second experiment showed that the difference between close and lax cutting became significant only when lax cutting was applied for at least half of the cuts each year. DM production was similar for treatments witii the same number of close or lax cuts, regardless of the time of year at which the two heights of cutting were applied.
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    Topics: Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition
    Notes: The effect of increasing annual fertilizer N application rate from 400 to 800 kg/ha (357 to 714 lb N/ac) and stocking rate from 5.0 to 7.5 animals per forage ha (2.02 to 3.04 animals per forage ac) on herbage availability, digestible OM intake and live weight gain was investigated in a grazing experiment repeated in 3 consecutive years. A 21×1 day rotational paddock grazing system was used in which the grazing area was increased in the ratio of 1:1.5:3 on two predetermined occasions.Increasing the fertilizer N application rate increased herbage availability by 12% but failed to increase live weight gain. Increasing stocking rate decreased herbage availability per ha and per animal, and also live weight gain per animal, but increased live weight gain per forage ha by 17.6%.
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    Topics: Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition
    Notes: A model is described which can be used to synthesize dairy systems under various price environments and sets of decision rules.The potential use of the model is illustrated with reference to the seasonal calving pattern as an economic decision.
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    Topics: Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition
    Notes: Different grazing treatments applied to pastures in which perennial ryegrass was dominant had little influence on DM production during the main reproductive growth period in late spring and early summer. Lax and infrequent grazing at this time did, however, reduce tiller density. During the dry summer period lax infrequent grazing increased production by 20%, while in the vegetative growth period in autumn those pastures which were alternately lax- and hard-grazed outyielded those which were hard grazed by 63%.In all treatments, initial recovery growth resulted almost exclusively from the production of leaf tissue. The rate of leaf growth declined three to five weeks after grazing, depending on treatment and season, and subsequent yield increase was dominated by sheath and stem growth.
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    Topics: Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition
    Notes: The liveweight gain was measured of beef cattle on pastures stocked at 5.9 to 11.8 cattle/ha and receiving 50, 182 or 329 kg N/ha in a 12-week season. N levels and stocking rates were so adjusted that similar yields of herbage per animal were expected. Results showed that similar liveweight gains per animal, averaging 1.03 kg/day, occurred at all N levels. Liveweight gain/ha ranged from 547 to 1037 kg in 12 weeks and the corresponding quantities of metabolizable energy utilized were 9890 and 17590 Meal. The results confinn earlier work (4, 7).
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    Notes: Three cutting heights, 2±5, 7±6 and 12±7 cm (1, 2±5 and 5 in.) and three levels of fertilizer N, 168, 280 and 392 kg N/ha (150, 250 and 350 Ib N/ac) were imposed on a sward of Italian ryegrass (Lolium multiflorum) cv. Irish. Lowering the cutting height and increasing the level of applied N increased the yield of herhage DM. Increasing the level of applied N had a greater effect on the chemical composition of the herbage than altering the cutting height
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    Source: Blackwell Publishing Journal Backfiles 1879-2005
    Topics: Geosciences , Physics
    Notes: Sub-bottom profilers achieve high resolution but limited penetration beneath the seabed. Marine seismic surveys with long streamers and conventional sources suffer from an incomplete CDP stack and an unnecessarily low signal frequency in the early part of the section. Consequently there is a depth interval over which the optimum resolution of the seismic reflection method is not achieved. This paper describes the design, conduct, and results of an experimental survey made to obtain high resolution sections (predominant frequency about 200 Hz) with reflection times up to one second in the northern North Sea. The prime motivation for the experiment was to assess the possibility of mapping a shallow gas sand which had been encountered by the drillers.The design concept of the survey was to keep all the benefits of conventional marine seismic data gathering and processing, but to reduce their dimensions and time scales by a factor of five to ten. The survey in 1972 recorded a total of twenty-four lines using twenty-four fold cover with 5 m spacing between the reflector points, and a separation of 50 m between adjacent lines. Multi-electrode sparkers were used with a shallow purpose-built twenty-four channel 240 m hydrophone streamer. The recording sample interval was 1 ms. The final sections, obtained after conventional data processing, were of good quality. The results of velocity analysis helped to distinguish primary and multiple energy. Reflections with large negative reflection coefficients were seen in some parts of the survey area, and these are thought to indicate thin gas sands.
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  • 90
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    Oxford, UK : Blackwell Publishing Ltd
    Geophysical prospecting 22 (1974), S. 0 
    ISSN: 1365-2478
    Source: Blackwell Publishing Journal Backfiles 1879-2005
    Topics: Geosciences , Physics
    Notes: This paper deals with a case study on the application of auto-correlation and spectral analysis methods to mineral assay data taken along seven drives and two winzes concerning the McTaggart's (West) lode of Kolar gold fields. The general model conceived in this study is: measured (estimated) ore grade at jth location =true value + error at jth location. Employing an auto-correlation function of the form C e- a |k| for signals, the respective contributions of signals and noise to the total logarithmic variances for the data along drives and winzes are analysed. Smoothed spectral density estimates and their 90% confidence limits are computed for the series of data.
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  • 91
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    Oxford, UK : Blackwell Publishing Ltd
    Geophysical prospecting 22 (1974), S. 0 
    ISSN: 1365-2478
    Source: Blackwell Publishing Journal Backfiles 1879-2005
    Topics: Geosciences , Physics
    Notes: Methods and typical case histories of EM and IP surveys are compared in order to check their compatibility for the investigation of large areas for base metal sulphides. It is demonstrated that the fast, low cost EM may miss sulphide concentrations which cause no reduction of apparent resistivity, or which act like horizontal slabs, where EM anomalies occur marginally. In such cases only IP can recognize the whole extent of the mineralization. The misleading role of graphite exists for both methods.The conclusion is that EM remains the only economical method to survey whole ore districts, but that the shortcomings should always be taken into account in the interpretation. They can be overcome by employing geological, geochemical or other geophysical indicators in selecting promising targets for follow-up IP. Even if less than 20% of the area is covered by the expensive IP, there is a fair chance that all sulphide bearing rocks will be found. Therefore, the question is not whether to apply EM or IP methods, but how to combine them best.
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  • 92
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    Oxford, UK : Blackwell Publishing Ltd
    Geophysical prospecting 22 (1974), S. 0 
    ISSN: 1365-2478
    Source: Blackwell Publishing Journal Backfiles 1879-2005
    Topics: Geosciences , Physics
    Notes: The paper deals with the prerequisites of application, specific peculiarities and methods of electrometric and thermometric investigations aimed at the solution of certain engineering-geological problems in offshore areas. Practical examples are supplied.
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  • 93
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    Geophysical prospecting 22 (1974), S. 0 
    ISSN: 1365-2478
    Source: Blackwell Publishing Journal Backfiles 1879-2005
    Topics: Geosciences , Physics
    Notes: The voltage induced in a horizontal loop on a layered ground has been calculated for the case where the loop is excited by a step current and measurements are made during the off-cycle.The expressions derived for a uniform ground show that for large time t the induced voltage E(t) is approximately given by E(t)≃— (Ibαμ/20t) (σμ2/t)3/2 where σ is the conductivity of the ground, μ the permeability, b the loop radius, and I the amplitude of the current step. For small times the corresponding result is E(t)≃—Ibμ/2t.When the ground is composed of a number of layers a numerical procedure for calculating the induced voltage is described.The calculated responses of various multilayered structures show that at short times the induced voltage is asymptotic to that produced in the case of a uniform ground of conductivity equal to the top layer.Interference effects in the top layer can lead to anomalous decay curves which may result in the underestimation of the conductivity of a buried layer.
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  • 94
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    Geophysical prospecting 22 (1974), S. 0 
    ISSN: 1365-2478
    Source: Blackwell Publishing Journal Backfiles 1879-2005
    Topics: Geosciences , Physics
    Notes: Marine geophysical work requires accurate navigation on a continuous basis. A repeatability of 150 m CEP (circular error probable) with sequential positioning of 15 m CEP is usually acceptable. Quoted figures for many presently available navigation systems yield nearly the required accuracy. In actual operations, however, such accuracies may not be achieved, and usually the performance actually realized cannot be determined for want of independent measurements for comparison. If more redundancy in navigation measurements were available on an integrated basis, the limitations of individual systems would no longer be so critical and the accuracy of measurements could be assessed in real time. Failures in navigation continue to occur. Such failures usually result from ignorance of the capabilities of the navigation system and limitations and consequent choice of a system which is not appropriate to the demands of a particular survey. The points to be covered in work standards are listed.
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  • 95
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    Geophysical prospecting 22 (1974), S. 0 
    ISSN: 1365-2478
    Source: Blackwell Publishing Journal Backfiles 1879-2005
    Topics: Geosciences , Physics
    Notes: The acceptance of articles in Geophysical Prospecting is strictly based on the originality and relevance of the contents. In order to be published a paper has to satisfy additional requirements on its external form and on its style and language: it should be written preferably in English though articles in French and German are permitted. A paper should consist of (i) a title page, (ii) an abstract, (iii) the text, (iv) list of references, (v) captions to illustrations, if any, (vi) tables, if any, and (vii) illustrations, if any. These seven parts should be mailed together but be physically separable and should be prepared according to rules which are either based on printing necessities or on the editorial style of the Journal.Failure to comply with these rules may result in delay in further processing of the article. Since Geophysical Prospecting is edited with a minimal budget correspondence with authors is kept to a minimum.
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  • 96
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    Geophysical prospecting 22 (1974), S. 0 
    ISSN: 1365-2478
    Source: Blackwell Publishing Journal Backfiles 1879-2005
    Topics: Geosciences , Physics
    Notes: Depths of investigation for normal (bipolar) and focusing (unipolar) linear electrode arrays have been computed following the method given earlier (Roy and Apparao 1971) both in homogeneous and layered earth. The focusing arrangement is found to be superior to normal arrangement both in regard to depth of investigation and zone of uniform depth of investigation. This analysis holds good in layered media too. Further, the depth of investigation increases with the increase in the length (2M) of the electrode and reaches a limit, 0.29L for normal and 0.50L for focusing, when the electrode attains an optimum length to satisfy the infinite condition. This optimum length of the electrode is six times the distance L of the observation point from the electrode for normal and about ten times for focusing. A contour diagram for contributions of individual ground elements to the total signal measured at the centre of focused system is also discussed.
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  • 97
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    Geophysical prospecting 22 (1974), S. 0 
    ISSN: 1365-2478
    Source: Blackwell Publishing Journal Backfiles 1879-2005
    Topics: Geosciences , Physics
    Notes: The authors generalize a method expounded in a previous paper (1971, Geoph. Prosp. 18, 786-799) to the case of a local conductivity σ(M) of the infinite medium satisfying the relation 〈displayedItem type="mathematics" xml:id="mu1" numbered="no"〉〈mediaResource alt="image" href="urn:x-wiley:00168025:GPR246:GPR_246_mu1"/〉 where the Ri's are the distances from the point M to n fixed points Si (i= 1,. n), k is a positive real constant and Ci, Cii are constants ensuring the condition α 〉 O.The sub-surface conductivity distributions (half-spaces) complying with (1) provide a wide variety of conducting structures, which can fit quite successfully the rather complicated distributions of conductivity occurring in natural ore bodies.An exact algebraic calculation of the apparent resistivity for these grounds, valid for any dc electrical prospecting devices (Wenner, Schlumberger, dipole, etc.) leads to a set of simultaneous linear equations, with a matrix which is invariant with respect to the position of the quadrupole being used. This greatly simplifies the numerical computation.We also present some examples of cross sections for the real and apparent resistivity obtained by this method.
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  • 98
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    Oxford, UK : Blackwell Publishing Ltd
    Geophysical prospecting 22 (1974), S. 0 
    ISSN: 1365-2478
    Source: Blackwell Publishing Journal Backfiles 1879-2005
    Topics: Geosciences , Physics
    Notes: Section migration after stack has been widely accepted by the industry. From a theoretical point of view, section migration before stack should provide superior results, the improvement warranting the drastically increased cost is not realized in most cases.There are a number of reasons that explain the discrepancy between actual and theoretically expected quality: Long period statics, refraction of rays, two-dimensional treatment of an actually three-dimensional problem.The section migration package subject to this paper allows(i) to take refraction into account,(ii) to discriminate against noise with a variety of statistical and geometrical criteria,(iii) to adapt processing time to problem complexity by a special process called SEMI-STACK.A number of examples will demonstrate the effects of section migration.
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  • 99
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    Oxford, UK : Blackwell Publishing Ltd
    Geophysical prospecting 22 (1974), S. 0 
    ISSN: 1365-2478
    Source: Blackwell Publishing Journal Backfiles 1879-2005
    Topics: Geosciences , Physics
    Notes: A seismic trace after application of suitable amplitude recovery may be treated as a stationary time-series. Such a trace, or a portion of it, is modelled by the expression 〈displayedItem type="mathematics" xml:id="mu1" numbered="no"〉〈mediaResource alt="image" href="urn:x-wiley:00168025:GPR627:GPR_627_mu1"/〉 where j represents trace number on the record, t is time, αj is a time delay, α (t) is the seismic wavelet, s(t) is the reflection impulse response of the ground and nj is uncorrelated noise. With the common assumption that s(t) is white, random, and stationary, estimates of the energy spectrum (or auto-correlation function) of the pulse α(t) are obtained by statistical analysis of the multitrace record. The time-domain pulse itself is then reconstituted under the assumption of minimum-phase. Three techniques for obtaining the phase spectrum have been evaluated: (A) use of the Hilbert transform, (B) Use of the z-transform, (C) a fast method based on inverting the least-squares inverse of the wavelets, i.e. inverting the normal time-domain deconvolution operator. Problems associated with these three methods are most acute when the z-transform of α(t) has zeroes on or near the unit circle. Such zeroes result from oversampling or from highly resonant wavelets. The behaviour of the three methods when the energy spectra are perturbed by measurement errors is studied. It is concluded that method (A) is the best of the three. Examples of reconstituted pulses are given which illustrate the variability from trace-to-trace, from shot-to-shot, and from one shot-point medium to another. There is reasonable agreement between the minimum-phase pulses obtained by this statistical analysis of operational records and those estimated from measurements close to the source. However, this comparison incorporates a “fudge-factor” since an allowance for absorption has to be made in order to attenuate the high frequencies present in the pulse measured close to the shot.
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  • 100
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    Geophysical prospecting 22 (1974), S. 0 
    ISSN: 1365-2478
    Source: Blackwell Publishing Journal Backfiles 1879-2005
    Topics: Geosciences , Physics
    Notes: The implementation of a stacking filter involves the filtering of each trace with an individual filter and the subsequent summing of all outputs. The actual position of a trace in space as well as certain simultaneous shifts of traces and filter components in time do not influence the process. The resulting output is consequently invariant to various arbitrary coordinate transformations. For a certain useful class of ensembles of non-linear moveout arrival times for signals a particular transformation can be found which transforms a given ensemble into one consisting only of straight lines. It is thus possible to reduce, for instance, the analysis of a stacking filter designed for hyperbola-like moveout curves to the analysis of a velocity filter with linear moveout curves. As the (f—k) transform is a very useful concept to describe a velocity filter, it can consequently be applied to characterize a stacking filter in regard to its performance on input signals with non-linear moveout.
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