ALBERT

Notes: The paper presents research and development at the Thematic Information Service of the Natural Environment Research Council (NERC) on the topic of integrated geographic information systems. The term integrated is used to describe the incorporation of vector digitised map data and raster scanned remotely sensed data within a single computational environment and with a single interface to the user. Point sampled and statistical data can also be handled by the system. The general structure and working of the Thematic Information Service (TIS) is described only to the extent that it is relevant to providing the background to the research or to highlighting why the specific approach described has been taken.

Notes: A procedure for digital image correlation is described which is based on least squares window matching. The immediate aim is high precision parallax assessment, point transfer, and point measurement. Experiments and theory have confirmed the high accuracy potential of the method. By implementation of charge coupled device (CCD) video cameras in an analytical plotter, an experimental hardware and software configuration has been established with which the operational on line application of digital image correlation for conventional photogrammetric measuring tasks can be tested. First results of calibration and performance of the system are presented. They allow optimistic conclusions as to the further development and practical application of digital image processing in photogrammetry.

Notes: Book review in this aticle:DESERTS AND ARID LANDS. Edited by F. El-Baz.IMAGES OF THE WORLD AN ATLAS OF SATELLITE IMAGERY AND MAPS. By C. Mueller-Wille with an interpretive supplement by R. M. Smith.ELEMENTS OF PHOTOGRAMMETRY. By P. R. Wolf.

Notes: The essential features of equipment for mobile processing are outlined with reference to the development of small photographic laboratory vehicles for use in the Jield. The resulting air film processor, the Wainco Products Limited 392. is described and details are given of trials carried out to establish its performance for a range of tasks in both reconnaissance and survey. The tests cover the sensitometric and drying behaviour of several air films in current use and include an analysis of the dimensional stability o f j l m in the processor. Applications using direrent containers and eflectiveness in improvised situations are also described and possible future variants of the processor are suggested.

Notes: This paper is concerned with a new technique (the terrestrial/photogrammetric (TP) technique) for the detection and compensation of systematic height errors in block aerial triangulation. The technique improves the height accuracy of such triangulation by reducing the original bridging distance, using new bands of corrected photogrammetric tie points as height control together with the original bands of the terrestrial (or ground) height control. A number of photogrammetric blocks with different characteristics and configurations have been tested in a comprehensive manner. The tests show that the TP technique gives consistent results over a wide range of circumstances and that it is a most effective, simple and inexpensive method for the compensation of systematic errors.〈section xml:id="abs1-2"〉〈title type="main"〉RésuméCet article relate une technique nouvelle permettant de détecter et de compenser les erreurs altimétriques systématiques dans l'aérotriangulation par blocs: la technique terrestre/photogrammétrique (TP). Cette technique améliore la précision altimétrique de l'aérotriangulation en réduisant la distance de l'aérocheminement original, grâce à l'utilisation d'un canevas de points d'appuis altimétriques composés de points de liaison photogrammétriques corrigés, en supplément du canevas original de points d'appui altimétriques déterminés sur le terrain.On a essayé de manière approfondie un grand nombre de blocs dotés de caractéristiques et de configurations diverses. Les essais montrent que la technique TP fournit des résultats fiables dans un large éventail de circonstances et que c'est une méthode de compensation des erreurs systématiques efficace, simple et peu coûteuse.〈section xml:id="abs1-3"〉〈title type="main"〉ZusammenfassungIm Artikel wird ein neues Verfahren behandelt (das terrestrisch-photogrammetrische Verfahren (TP)), das zur Aufdeckung und Kompensation system-atischer Höhenfehler in der Block triangulation dient. Es wird die Höhengenauigkeit durch Verkürzung der ursprünglichen Überbrückungsdistanz verbessert, indem neue Streifen korrigierter Verbindungspunkte als Höhenpasspunkte zusammen mit den ursprünglichen Reihen der terrestrischen Höhenpasspunkte verwendet werden. Eine Anzahl photogrammetrischer Blöcke unterschiedlicher Figur und Charakteristik wurde umfassend getestet. Die Tests zeigen, dass die TP-Methode konstante Ergebnisse für einen grossen Bereich van Möglichkeiten ergibt und dass es ein höchst effektives, einfaches und billiges Verfahren zur Eliminierung systematischer Fehler ist.

Notes: The development of an automated photographic measuring system (APM) is described. A very accurate laser beam scanning microdensitometer is used to digitise the photographic plate and a series of on line computers analyses the data during scanning. The system is available as a national facility for United Kingdom astronomers and guest investigators.〈section xml:id="abs1-2"〉〈title type="main"〉RésuméOn décrit un systéme automatisé de saisie de données sur cliché. Un microdensitométre à laser numérise la plaque photographique et les données sont analysées en temps réel par ordinateur. Le systeme est destiné aux astronomes du Royaume Uni et aux chercheurs y séjournant.〈section xml:id="abs1-3"〉〈title type="main"〉ZusammenfassungBeschreibung eines automatisierten photographischen Messsystems (APM). Ein hochgenaues Laser-Mikrodensitometer wird dabei zur Digitalisierung der Bilder benutzt, undeine Serie von On-line-Rechnern analysiert die Daten während der Abtastung. Das System steht für Astronomen im Vereinigten Königreich und anderen Forschern zur Verfügung.

Notes: During June and July 1981, synthetic aperture radar imagery was acquired of selected sites in ten European countries as part of the European SAR 580 campaign. Evaluation of this imagery in the UK will be carried out by 18 approved experiments (out of 56 for Europe) when the processed data becomes available to investigators. To assist the evaluation process, a review is given of some recent research on applications of imaging radar in agricultural and urban areas. Research is described which considered the effects of terrain parameters and radar parameters on crop classification accuracy. The relative merits of a quantitative or a qualitative approach in classification of radar data are considered. Combined use of radar and Landsat data achieves a marked improvement in classification accuracy. The development of spatial filtering techniques may assist in the problem in urban areas resulting from the dependence of image tone on the relative alignment of ground features and radar look direction.〈section xml:id="abs1-2"〉〈title type="main"〉RésuméPendant les mois dejuin et juillet 1981, on a, dans le cadre de la campagne européenne SAR 580, recueilli des données de radar imageur à synthèse d'ouverture sur des sites choisis dans une dizaine de pays d'Europe. Ces données seront évaluées au Royaume-Uni au moyen de 18 expériences ayant été acceptées (sur un total de 56 menées en Europe); ce travail commencera dès que les données une fois traitées seront distribuées aux chercheurs. Pour accompagner cette procédure d'evaluation, on fournit une analyse de quelques recherches récentes sur les applications de l'imagerie radar aux zones agricoles et urbaines.L'une de ces recherches prenait en compte les effets des paramètres liés au terrain sur l'exactitude de la classification des cultures. Les mérites réciproques des approches quantitatives et qualitatives dans la classification des données radar sont également examinés.Le recours à une combinaison de données radar et Landsat permet d'améliorer de manière significative l'exactitude de la classification. La mise en oeuvre des techniques de filtrage spatial peut aider à réduire, dans les zones urbaines, les conséquences néfastes sur la tonalité de l'image, d'objets au sol en alignement relatif avec la direction d'observation du radar.〈section xml:id="abs1-3"〉〈title type="main"〉ZusammenfassungIm Juni und Juli 1981 erfolgten Radaraufnahmen mittels synthetischer Apertur von ausgewählten Gebieten in 10 europäischen Ländern als Teil der Europäischen SAR 580 Kampagne. Die Analyse dieser Aufzeichnungen wird im Vereinigten Königreich durch 18 (aus insgesamt 56 für Europa) bestätigte Experimente erfolgen, nachdem die Daten zur Verfügung stehen. Um den Analysenprozess zu unterstützen, wird ein Überblick über kürzliche Forschungen zu Radaraufzeichnungen in landwirtschaftlichen und städtischen Gebieten gegeben. Es werden auch Forschungen beschrieben, bei denen die Einflüsse von Geländeparametern auf die Genauigkeit der Ernteklassifizierung untersucht wurden. Der relative Wert eines quantitativen oder qualitativen Versuchs zur Klassifizierung von Radardaten wird abgeschätzt. Eine Kombination von Radarund Landsat-Daten ergibt eine merkliche Verbesserung bei Klassifizierungsgenauigkeit. Die Entwicklung von Verfahren der räumlichen Filterung kann von Wert bei städtischen Gebieten sein, weil es eine Abhängigkeit des Grauwertes von der relativen Ausdehnung von Geländecharakteristika und der Richtung der Radaraufnahme gibt.

Notes: Some aspects of the XYZBLC suite of programs for aerial triangulation are described. The Ordnance Survey Bute block of photography at a scale of 1: 24000 is computed by independent models using XYZBLC. Three of the strips in the block are treated as a test block and are computed with different configurations of control. Conclusions are drawn with regard to the usefulness of height control doublets and other dense control configurations.〈section xml:id="abs1-2"〉〈title type="main"〉Résumé Quelques aspects de l'ensemble XYZBLC de logiciels d'aérotriangulation sont décrits. Le bloc Bute de l'Ordnance Survey, composé de photographies à l'échelle du 1: 24000, a été calculé par modèles indépendants avec les logiciels XYZBLC. On a considéré trois des bandes du bloc comme formant un bloc d'essai et on les a calculées avec diverses combinaisons de canevas de points d'appui. On en tire des conclusions quant à l'utilité des doublets de points d'appui altimétriques et de diverses autres configurations denses de canevas d'appui. 〈section xml:id="abs1-3"〉〈title type="main"〉Zusammenfassung Beschreibung einiger Aspekte des XYZBLC-Programmsystems zur Aero-triangulation. Ein Block des Ordnance Survey im Bildmassstab 1: 24000 wurde damit nach der Methode der unabhängigen Modelle berechnet. Drei der Streifen des Blocks wurden als Testblock behandelt und mit verschiedenen Passpunktanordnungen berechnet. Es werden Schlussfolgerungen in bezug auf die Nützlichkeit von Zwillingspunkten zur Höhenorientierung und andere dichte Passpunktanordnungen gezogen.

Notes: The wide availability of reconnaissance frame photography, together with the advantage of high image resolution that such photography provides and the extreme flight conditions under which it can be taken, means that it is of great interest to photogrammetrists. However, the geometry of the image is invariably distorted due to the mode of operation of the camera. In this paper, the effects of the focal plane shutter and apparent image motion compensation on the geometry of the photographs are considered.〈section xml:id="abs1-2"〉〈title type="main"〉RésuméLe fait que la photographic de reconnaissance soil très répandue, conjointe-ment aux avantages que présente la grande résolution des images fournies par ces systèmes et les conditions extrêmes de vol dans lesquelles on peut les prendre, milite pour une prise en compte de lew intérêt par les photogrammètres. Toutefois la géométrie de ces images est systématiquement déformée par suite du mode de fonctionnement de la chambre. On traite dans cet article des effets de l'obturateur focal et de la compensation du filé de l'image sur la géométrie des photographies.〈section xml:id="abs1-3"〉〈title type="main"〉ZusammenfassungDie grosse Verbreitung von Erkundungsfotos zusammen mit der grossen Auflösung solcher Fotos und den extremen Bedingungen unter denen sie auf-genommen wurden, lassen diese auch für den Photogrammeter interessant erscheinen. Die Geometrie dieser Bilder ist jedoch infolge der speziellen Kamera-funktion verzerrt. Im Artikel werden die Einflüsse des Schlitzverschlusses und des Bildwanderungsausgleichs auf die Bildgeometrie untersucht.

Notes: Book Reviewed in this article:AERIAL PHOTOGRAPHY. By G. S. Kumar.MANUAL OF PHOTOGRAMMETRY (Fourth Edition). Editor-in-Chief: C. C. Slama.

Notes: Two complementary measuring instruments are described which use a very simple principle and which take three dimensional measurements or plots directly from small objects. The first instrument can achieve accuracies of ± 0·3 mm on objects whose largest dimension is 300 mm. The second can achieve ± 0·02 mm on objects smaller than a 25 mm cube.〈section xml:id="abs1-2"〉〈title type="main"〉RésuméOn présente deux instruments de mesure complémentaires el de principe très simple permettant de relever dans l'espace des coordonnées sur de petits objets, le premier avec une exactitude de ± 0.3 mm sur des objets de dimension inférieure à 300 mm, le second avec une exactitude de ± 0.02 mm sur des objets de dimension inférieure à 25 mm.〈section xml:id="abs1-3"〉〈title type="main"〉ZusammenfassungBeschreibung von zwei Zusatzmessgeräten, die auf einem sehr einfachen Prinzip beruhen und mit denen dreidimensionale Messungen oder Auswertungen von kleinen Objekten direkt durchgeführt werden konnen. Mil dem ersten Gerät kann eine Genauigkeit von ± 0,3 mm bei maximalen Objekt abmessungen von 300 mm und mit dem zweiten von ± 0,02 mm bein Objekten, die kleiner als ein 25 mm-Kubus sind, erreicht werden.

Notes: This paper outlines the technical procedures used in commercial orthophotomap production and attempts to identify some of the main differences in technical approach between orthophotomapping and conventional line mapping.〈section xml:id="abs1-2"〉〈title type="main"〉RésuméOn décrit les techniques industrielles de production d'orthophotocartes et on compare leur emploi avec celui des techniques classiques.〈section xml:id="abs1-3"〉〈title type="main"〉ZusammenfassungSkizzierung der Technologien, die bei der kommerziellen Herstellung von Orthofotokarten angewendet werden, wobei versucht wird, die hauptsächlichen Unterschiede der Techniken zur Herstellung von Orthofotokarten und konventionellen Strichkarten aufzudecken.

Notes: This paper investigates the effect of the deviation of measured points from the standard locations when carrying out a relative orientation of a stereomodel. The analytical solution of more than 100 cases was considered and, for each case, the weights for the elements of relative orientation and the correlation coefficients were evaluated. The stability of the solution was studied by calculating the characteristic roots of the matrix of normal equations.It is shown that, theoretically, the solution of the relative orientation problem can always be achieved whenever the locations of the measured points satisfy stated geometrical requirements. However, the reliability of the solution depends on their exact positions in the stereomodel. When the accuracy is too low, in practice there is no solution.〈section xml:id="abs1-2"〉〈title type="main"〉RésuméOn étudié l'effet sur l'orientation relative d'un couple de variations de position des points de base. Plus de 100 cas ont été considérés et à chaque fois ont été estimées les précisions des paramètres calculés ainsi que leur correlation. On a de plus, étudié la stabilité de la solution par l'intermédiaire des valeurs propres de la matrice normale.Il n'est pas indispensable, en principe, d'imposer de contraintes précises au choix des points de base; mais de ce choix dépend la fiabilité de la solution, faible s‘il est par trop fantaisiste.〈section xml:id="abs1-3"〉〈title type="main"〉ZusammenfassungIn der Arbeit wird der Einfluss der Abweichung der gemessenen Punkte von ihrer Standardlage bei relativer Orientierung eines Stereomodells untersucht. Dazu werden mehr als 100 analytische Lösungen analysiert und für jeden Fall die Gewichte der Elemente der relativen Orientierung und die Korrelationskoeffizienten berechnet. Die Stabilität der Lösung wurde durch Berechnung der charakteristischen Wurzeln der Matrix der Normalgleichungen abgeschätzt.Es wird gezeigt, dass theoretisch immer die Lösung des Problems der relativen Orientierung erreicht werden kann, sobald die Lage der Messpunkte die geometrischen Anforderungen erfüllt. Die Zuverlässigkeit der Lösung hängt jedoch von der exakten Lage der Punkte ab. Wenn ihre Genauigkeit zu gering ist, gibt es praktisch keine Lösung.

Notes: Underwater photogrammetry is being used in the particularly hostile environment of the North Sea where it has been put into commercially viable operation. The authors discuss underwater photogrammetry related to other means of inspection of oil platforms. They also deal with operational experience of 35 mm and 70 mm cameras, camera calibration, the provision of control and photogrammetric observations and data analysis. The demand for underwater photogrammetry continues to grow.

Notes: The author reviews the historical background of the analytical orthoprojector and examines the design requirements for this instrument. The construction and performance of the Zeiss (Oberkochen)Z2 orthoprojector are described and an assessment is made of its practical advantages.

Notes: The new APY (Analytical Photogrammetry Yzerman) system is described and a detailed explanation is given of the principles involved. The APY depends on a unique modular design. A list of the straightforward operations required for its application in data compilation and revision is included.

Notes: The application of phorogrammetry to the measurement of deformation is discussed and four different approaches are identified and compared. References to and summaries of recent work are made.

Notes: The development and operation of an inexpensive retractable vertical camera rig is described. Unlike several commercially available camera packages, the cameras on this rig are accesible in flight thus permitting the changing of magazines and other operations. Since the camera carriage is only deployed when over the site to be photographed, the aircraft performance is not degraded during positioning flights.

Notes: This paper summarises the theoretical and practical development of’an analytical system for close range photogrammetry. The system uses the extended bundle method of phototriangulation and a sophisticated least squares algorithm. A description is given of computer software, and aspects of statistical testing and gross error detection are discussed in order to assess the accuracy potential. Applications of the system, for precise co-ordination of a target range and camera calibration are outlined.

Notes: A photogrammetric system that is suitable for shallow water detailed mapping at scales from 1:50 to 1:500 for coastal and harbour engineering projects is described. The results from tests using automatic 35 mm Canon cameras on an elevated platform to determine the accuracy of planimetric and depth co-ordinates are presented. The economic benefits of stereophotography through shallow water rather than underwater photography are discussed.

Notes: This paper reviews the growth in the use of photogrammetric techniques in architecture, principally in the United Kingdom, over the past ten years. The work of the various establishments involved in architectural photogrammetry is described and the results of a questionnaire, distributed within the architectural profession, are analysed. Some comparisons are made with developments elsewhere in Europe.〈section xml:id="abs1-2"〉〈title type="main"〉RésuméOn examine dans cet article l'extension qu'a connue l'utilisation des méthodes photogrammétriques en architecture au cows des dix dernières années, principalement dans le Royaume-Uni. On y décrit les travaux des divers organismes impliqués dans la photogrammétrie architecturale et l'on y analyse les résultats d'un questionnaire diffusé au sein de la profession liée à l'architecture. On fournit enfin quelques comparaisons avec les développements constatés par ailleurs en Europe.〈section xml:id="abs1-3"〉〈title type="main"〉ZusammenfassungIm Artikel wird über die zunehmende Anwendung photogrammetrischer Verfahren während der letzten 10 Jahre in der Architektur, insbesondere im Vereinigten Königreich, berichtet. Die Arbeit verschiedener Institutionen, die sich mit Architekturphotogrammetrie befassen, wird beschrieben, und es werden die Ergebnisse eines unter Architekten verteilten Fragebogens analysiert. Weiterhin werden Vergleiche zu Entwicklungen in anderen europäischen Ländern gezogen.

Notes: An individual view is provided of the function of the art and science of photogrammetry, over the whole of the history of attempts to make measurements from optical observations. The predominating influence, in past years, of the need for mapping from air photographs is compared with the prospect that increasing demands for similar facilities in close range measurement, for application in fields such as mechanical engineering, medicine and architecture, may soon be seen to give further encouragement to the development of the subject. The author makes use of illustrations from his experience to point out simple cases where the potential of photogrammetric techniques, in the wider sense, has not been appreciated.

Notes: The algorithm presented assumes a preliminary determination of the elements of inner orientation and bases its mathematical model on the collinearity condition, from which projective equations are derived. Linearisation of condition equations is based on Taylor's expansion, whilst the subsequent solution follows iteration cycles. The method aims to derive composite corrections to image coordinates, with the aid of test field data.〈section xml:id="abs1-2"〉〈title type="main"〉RésuméL'auteur présente un algorithme oú l'on suppose déterminés au préalable les éléments d'orientation interne. La modélisation mathématique s'appuie sur les conditions de co-linéarité et sur les équations qui en résultent en projection. On linéarise les équations de conditions en utilisant un développement en série de Taylor, et l'on obtient la solution correspondante par itération. La méthode vise à apporter des corrections aux coordonnées images en utilisant les données d'un polygone d'essai.〈section xml:id="abs1-3"〉〈title type="main"〉ZusammenfassungBei dem dargestellten Algorithmus wird die vorläufige Bestimmung der Elemente der inneren Orientierung angenommen, und das mathematische Modell basiert aufder Kollinearitätsgleichung, woraus perspektive Gleichungen abgeleitet werden. Die Linearisierung der Bedingungsgleichungen erfolgt durch Anwendung der Taylor-Reihe, was für die folgenden Berechnungen einen iterativen Prozess bedingt. Mit der Methode wird angestrebt, Bildkoordinaten mit Hilfe von Testfelddaten zu verbessern.

Notes: There is a growing interest in the potential of synthetic aperture radar (SAR) for mapping and for gathering intelligence for map revision. This paper first gives a simple guide to the characteristics of SAR and then describes a study carried out to investigate the geometric properties of the imagery and the information content which is of interest for topographic mapping and the production of large scale plans. The conclusions cautiously indicate a potential although better quality images are required and more information must be known about the optimum conditions which should obtain when the data are recorded.〈section xml:id="abs1-2"〉〈title type="main"〉RésuméOn assiste à un intérét croissant envers le radar à ouverture synthétique (SAR) et ses possibilityés pour la cartographie et pour la collecte de renseignements utiles à la révision. Ce texte commence par donner un simple rappel des caractéristiques de ces radars pour décrire ensuite une étude effectuée sur le contenu informatif et les proprietyés géométriques de l'imagerie radar, qui intèresse la cartographie topographique et la confection de plans à grande échelle.Les conclusions font prudemment état d'une potentialité mais soulignent qu'il faudrait disposer d'images de meilleure qualityé et avoir davantage d'informations sur les conditions optimales à respecter lors de l'enregistrement des données.〈section xml:id="abs1-3"〉〈title type="main"〉ZusammenfassungEs besteht zunehmendes Interesse an den Möglichkeiten von Radaraufnahmen mittels synthetischer Apertur (SAR) zur Kartenherstellung und Erfassung von Daten zur Laufendhaltung. Zunächst wird im Artikel eine einfache Einführung in die SAR-Charakteristika gegeben. Dann erfolgt eine Beschreibung eines Versuches zur Untersuchung der geometrischen Eigenschaften und des Informationsgehalts, der von Interesse für die Herstellung topographischer und grossmassstäbiger Karten ist. Vorsichtige Schlussfolgerungen ergeben Möglichkeiten zur Verwendung solcher Informationen, wobeijedoch eine bessere Bildqualität zu fordern ist. Auch müssen noch mehr Kenntnisse über die optimalen Bedingungen bezüglich der Datenregistrierung bestehen.

Notes: An automatic plotting instrument development is described where the coordinate corrections are introduced in the optical system and not at the photograph. It is suggested that the opto-mechanical devices used for correction and the proposed use of microprocessors for control of these devices offer the possibility of producing a low cost automatic plotter and stereocomparator.〈section xml:id="abs1-2"〉〈title type="main"〉RésuméOn decrit une solution au probléme de la correction des coordonnées cliché pour le restituteur analytique et le stéréocomparateur: ces corrections sont introduites dans la partie optique du système et commandées par l'intermédiaire de microprocesseurs. Ceci devrait permettre d'abaisser le coût de ce type d'appareil.〈section xml:id="abs1-3"〉〈title type="main"〉ZusammenfassungBeschreibung eines automatischen Auswertegerätes, bei dem die Koordinatenkorrekturen nicht den Bildträgern, sondern dem optischen System zugeführt werden. Es wird angenommen, dass die zur Korrektur verwendeten optisch-mechanischen Vorrichtungen und die vorgeschlagene Verwendung von Mikroprozessoren zu deren Steuerung die Möglichkeit zum Bau eines billigen automatischen Auswertegerätes und Stereokomparators bieten.

Notes: Landsat multispectral scanner (MSS) and return beam vidicon (RBV) image data in both analogue and digital formats were used to assess the performance of the MSS and RBV sensor systems, and to determine their potential for recording information associated with topographic or land use maps of selected Chinese study areas (Beijing, Tianjin and the Huang He elbow). MSS images permitted the detection of 40 per cent to 50 per cent of the features identified on maps of 1: 250000 scale and larger, whereas the higher resolution Landsat 3 RBV images provided 10 per cent to 20 per cent additional information. Completeness of information extracted from a colour cathode ray tube display exceeded that obtained from analogue single band black and white MSS images by only 5 per cent to 10 per cent. Only through major improvements in spatial resolution will it be possible to compile maps at scales of 1: 250000 and larger from satellite data. Significantly, it appears that instantaneous field of view values of 5 m to 10 m will be required to produce image data of sufficient resolution for topographic mapping or detailed thematic studies of the Asian environment.〈section xml:id="abs1-2"〉〈title type="main"〉Résumé On a utilisé les données de l'imagerie spatiale provenant du scanneur multispectral (MSS) et du tube vidicon à retour de faisceau (RBV) de Landsat, à la fois sous forme analogique et numérique, pour évaluer la performance des systèmes de capteurs MSS et RBV, et pour déterminer leur aptitude à contenir l'information figurant dans les cartes topographiques et les cartes d'occupation du sol, sur des polygones d'essais sélectionnés en Chine (Pekin, Tianjin, et le coude du Huan He). Les images MSS ont permis de détecter 40 à 50 pour cent des détails figurant sur les cartes à une échelle supérieure ou égale à 1: 250000, tandis que les images RBV à meilleure résolution de Landsat C fournissaient 10 à 20 pour cent d'informations supplémentaires. Le volume des informations extraites sur un écran cathodique de visualisation en couleurs n'a dépassé le volume obtenu à partir d'images d'une seule bande MSS en noir et blanc que de 5 à 10 pour cent seulement. Il semble que ce ne soit que par des améliorations importantes dans la résolution spatiale que l'on pourra tirer des données de satellites des cartes à des échelles supérieures ou égales à 1: 250000. Il apparait de manière significative qu'un champ instantané de prise de vues de 5 à 10 m (pixel) sera nécessaire pour obtenir des images ayant une résolution suffisante pour la cartographie topographique ou pour des études thématiques détaillées sur l'environnement asiatique.〈section xml:id="abs1-3"〉〈title type="main"〉Zusammenfassung Verwendung von Landsat-aufzeichnungen, die mit Hilfe des multispektralen Scanners (MSS) und des Return Beam Vidicon (RBV) aufgenommen wurden und sowohl in analoger als auch digitaler Form vorlagen. um die Leistungsfähigkeit dieser Aufnahmesysteme zu ermitteln und die Möglichkeiten zur Gewinnung von Informationen zur Herstellung von topographischen oder Landnutzungskarten in ausgewählten chinesischen Versuchsgebieten (Beijing, Tianjin undder Huang He Bogen). MSS-Bilder gestatteten die Erkennung von 40 bis 50% der auf Karten im Massstab 1: 250 000 oder grösser identifizierten Objekte, während die RBV-Bilder von Landsat 3, die eine grössere Auflösung hatten, 10 bis 20% zusätzliche Informationen lieferten.Die Vollständigkeit der Information, die von einem Farbdisplay erhalten wurde, überstieg die von analogen einkanaligen schwarzweissen MSS-Bildern erhaltenen nur um 5 bis 10%. Nur durch wesentliche Verbesserungen der Objektauflösung wird es möglich sein, Karten 1: 250000 und grösser nach Satellitendaten herzustellen. Es wird offensichtlich eine Objecktauflösung von 5 bis 10m gefordert, um Bilddaten genügender Auflösung für die Herstellung topographischer Karten oder thematischer Studien des asiatischen Raums zu erzeugen.

Notes: The paper deals with the analytical plotter and its impact on numerical photogrammetry. A short introductory section is followed by examples of the use of a Zeiss (Oberkochen) Planicomp C100 in analytical aerial triangulation, close range photogrammetry and the generation of digital height models. The examples demonstrate the suitability of the analytical plotter for numerical photogrammetry. Computer assistance and computer control allow for advanced data acquisition of high accuracy and speed. In addition, the minicomputer controlling the analytical plotter can be used for subsequent data processing. As a result, projects involving numerical photogrammetry can be carried out entirely in-house, without the need of an external computer.〈section xml:id="abs1-2"〉〈title type="main"〉RésuméLe restituteur analytique et la photogrammétrie numérique. On cite des applications du Planicomp C100: aérotriangulation analytique, photogrammétrie à courte distance, constitution de modéles numériques de terrain. Efficacité, rendement, haute exactitude, tels sont les avantages du restituteur analytique. On peut d'autre part bénéficier de l'ordinateur pour toutes sortes de traitements ultérieurs.〈section xml:id="abs1-3"〉〈title type="main"〉ZusammenfassungDer Beitrag beschäftigt sich mit dem Analytischen Plotter (AP) und seiner Auswirkung auf die Numerische Photogrammetrie. Nach einem kurzen Einführungsteil wird über den Einsatz eines Zeiss (Oberkochen) Planicomp C100 in der Analytischen Aerotriangulation, in der Nahbereichsphotogrammetrie und beim A ufbau Digitaler Höhenmodelle berichtet. Die Beispiele veranschaulichen die Eignung des AP für die numerische Photogrammetrie. Einerseits erlauben Rechnerstützung und Rechnersteuerung eine allgemeine, genaue und schnelle Datengewinnung. Darüberhinaus aber ermöglicht der, für die Steuerung des AP verfügbare Minicomputer die rechnerische Weiterverarbeitung der Messdaten. Auf diese Weise können numerisch-photogrammetrische Projekte ohne Einsatz eines externen Computers vollständig bearbeitet werden.

Notes: Book Reviewed in this article:SPHERE, SPHEROID AND PROJECTIONS FOR SURVEYORS. By J. E. Jackson.REMOTE SENSING IN ARCHAEOLOGY, CULTURAL RESOURCES TREATMENT AND ANTHROPOLOGY: THE UNITED STATES OF AMERICA IN 1979. By J. I. Ebert and T. R. Lyons.A HISTORY OF ARCHAEOLOGICAL AIR PHOTOGRAPHY IN GREAT BRITAIN. By R. R. Downey.PROCEEDINGS OF THE INDUSTRIAL AND ENGINEERING SURVEY CONFERENCE, LONDON, 1980. Edited by M. A. R. Cooper.ANALYSIS AND ADJUSTMENT OF SURVEY MEASUREMENTS. By E. M. Mikhail and G. Gracie.A HISTORY OF THE ORDNANCE SURVEY. Edited by W. A. Seymour.IN FOCUS: a rated guide to the best in photographic equipment. By J. Holtz.MAPS AND SURVEYS OF MALAWI. By C. G. C. Martin and other contributors.

Notes: When a member is thought to be domiciled or employed abroad, the name of the country has been added. Errors and omissions should be notified to the Honorary Secretary.

Notes: A brief review of work on airborne metric camera movement has been made. The tolerances for permissible image movement set by various investigators are discussed.The biggest single fault with most metric camera mountings in current use is that the centre of gravity of the camera is well above the line of action of the resilient elastic restoring forces. This results in coupling between the linear vibration of the airframe and the angular motion of the camera. There is a need for a simple device which can be attached to a survey camera in order to record angular motion during actual survey missions.〈section xml:id="abs1-2"〉〈title type="main"〉RésuméAprès une brève revue des travaux concernant les mouvements d'une chambre de prise de vue en vol, on discute les tolérances couramment admises pour ces mouvements.Le défaut de montage le plus fréquemment rencontré, est que le centre de gravité de la chambre est au-dessus de la ligne d'équilibre des forces agissantes.D'où un couplage entre la vibration longitudinale du porte-chambre et le mouvement angulaire de la chambre. Il faudrait créer un dispositif simple permettant d'enregistrer ce mouvement pendant les vols.〈section xml:id="abs1-3"〉〈title type="main"〉ZusammenfassungEs wird ein kurzer Überblick über die Arbeiten zur Bewegung von Luftbildmesskammern gegeben. Die von verschiedenen Autoren für die zulässige Bildwanderung angegebenen Toleranzen werden diskutiert. Der schwerwiegendste Fehler, der am meisten bei den gegenwärtig verwendeten Messkammern auftritt, ist der, dass der Kammerschwerpunkt über der Wirkungslinie der schwingungsdämpfenden Kräfte liegt. Daraus resultiert eine Paarung der linearen Vibration mit der Winkelbewegung der Kammer. Es besteht Bedarf für eine einfache Vorrichtung, die an einer Messkammer befestigt werden kann, um die Winkelbewegungen während des Bildflugs aufzuzeichnen.

Notes: A method of delineating the extent of floods has been devised involving the establishment of flood surfaces and the creation of photogrammetric digital terrain models. These two data sources are combined in a computer aided map production system and comparisons are drawn between the efficacy of different forms of terrain modelling in a floodplain environment.〈section xml:id="abs1-2"〉〈title type="main"〉RésuméOn a mis au point, en vue de déterminer l'étendue d'innondations, une méthode numérique combinant les notions de surface innondable et de modèle numérique de terrain (MNT); on se pose le problème du choix du MNT dans un environnement de plaine innondable.〈section xml:id="abs1-3"〉〈title type="main"〉ZusammenfassungAngabe eines Verfahrens zur Ableitung der Ausdehnung von Überschwemmungen, wobei die Flut-Oberfläche bestimmt und photogrammetrisch digitale Geländemodelle erzeugt werden. Diese beiden Datenquellen werden in einem rechnergestützten Kartiersystem kombiniert, und es werden Vergleiche bezüglich der Wirksamkeit verschiedener Verfahren der Geländemodellierung in Flussniederungen gezogen.

Notes: The existence of high-density, nearly-structureless bedrock buried by relatively low-density sediments makes gravity prospecting a very informative technique for bedrock-topography studies of the northern Appalachian Plateaus. Locating bedrock exposures and using available well data reduces the area of the gravity search. Depths to bedrock from wells correlate excellently with depths from gravity anomalies. The minimum anomaly detected was 0·18 milligal, corresponding to a depth of approximately 40 feet.

Notes: A comparative study was undertaken on the decay rates of three bacterial types (S. typhimurium, E. coli and S. faecalis), an enterovirus (poliovirus type 1) and a bacterial phage (f2) in ground water maintained under laboratory conditions. Except for f2 phage, all the microorganisms tested were relatively stable in ground water. S. faecalis survived best among all the bacteria tested and its decay rate was similar to that of poliovirus type 1.Under field conditions, bacterial indicators were also found to be stable in the ground-water environment. The decay rate for fecal streptococci was lower than for fecal or total coliforms in the shallow wells.

Notes: A technique has been developed for the determination of the exchangeable cation population of calcareous sandy material with cation exchange capacities of less than 1 meq/100 g. The technique involves the addition of exchange salt in the dry state to samples of porous media using original pore water as the exchange salt solvent. In applying this technique to samples from below the water table, the amount of pore water available for reaction is reduced by centrifuging in the field to bring the moisture content close to field capacity values. By utilizing the minimum amount of pore water, interferences during the exchange process due to calcite precipitation or dissolution are minimized. The extent of calcite dissolution or precipitation that occurs can be appraised by measuring alkalinity or total carbon on the pore water before and after addition of the exchange salt. Three salts, NH4C1, CsCl and LiCl were tested for their suitability for this technique. CsCl was found to be preferable because of its low tendency to dissolve carbonate and the preference of Cs+ on exchange sites.Application of the method to a field site in southern Ontario yielded a value of 0.51 ± 0·09 meq/100 g over 15 samples for the cation exchange capacity of a near surface glaciofluvial sand deposit. It is believed that this technique could be applied with reasonable accuracy and reproducibility to materials with exchange capacities of as low as 0·1 meq/100 g.

Notes: The upconing of the salt-water interface in an unconfined coastal aquifer due to water withdrawal by an infiltration gallery is analyzed numerically based on the variational formulation of the problem. Sometimes in coastal areas, from the point of view of safe withdrawal of water on a long-term basis, the use of an infiltration gallery is found to be feasible in preventing severe upconing of the interface that would have resulted from heavy pumpage by a vertical well. The numerical procedure presented here is capable of delineating profiles of the free surface and interface along with the length of the outflow face and quantity of freshwater flow to the sea. Full consideration of the nonlinear boundary conditions on the free surface and interface is included for a steady flow towards a gallery in both isotropic and anisotropic aquifers. The extent of upconing of the interface under different operating conditions of the gallery for different aquifer geometries has been studied. A general understanding of the flow phenomenon in the vicinity of the gallery has been established. The results of the analysis can be used to plan a water withdrawal scheme without causing contamination by salt water.

Notes: The streambed-leakage factor ranged from 0.11 to 1.68 million gallons per day per acre per foot of head loss. Most values for the streambed infiltration rate and the streambed-leakage factor for six tests before 1970 were higher than for six tests in 1976–79, suggesting a change in streambed permeability in the intervening time.A well field to serve a government-owned uranium enrichment facility, consisting initially of 4 wells, later increased to 15 wells, was designed to yield up to 20 million gallons per day. The wells are on a line parallel to the river at distances from the stream ranging from 122 to 330 feet. Distance between wells ranges from 190 to 303 feet. Specific capacities of the wells, based on 24-hour acceptance tests, ranged from 63 to 147 gallons per minute per foot of drawdown and averaged 100 gallons per minute per foot of drawdown. By late Summer of 1976, pumpage from all 15 wells ranged from 12 to 15 million gallons per day. Drawdown was about as expected, based on design criteria developed from the aquifer tests, except that pumping levels were lower than expected in the Fall and Winter of 1976–77, resulting from low streamflow and low river temperature.

Notes: Vast deposits of oil shale are contained in the Piceance basin in northwestern Colorado. The basin may contain as much as 40 million acre-feet of stored water associated with these deposits, much of which may have to be drained for mining. Yet, most analyses of watersupply for oil-shale development have focused on surface water with only brief mention of ground water.This study used a synthetic streamflow model to investigate the effects of using conservative estimates of ground water on the required active storage capacity of a hypothetical reservoir on the White River. Results of the study indicate that use of ground water from mine drainage and/or auxiliary wells may have a significant impact on the size and timing of surface-water reservoirs. Thus, ground water may be an important source of supply, particularly during early development of an oil-shale industry. The study results strongly suggest that further investigations are needed on the physical availability of ground water as well as the institutional, legal and waterquality constraints on its use.

Notes: Egypt is presently involved in a comprehensive program of land reclamation. Surface water has already been exhausted in meeting the urgent needs of agricultural expansion. If irrigation efficiency were increased, large amounts of surface water would be saved. However, this entails complex social, technical and political problems outside the scope of this paper. Ground-water development has priority over increasing irrigation efficiency (which would take a longer time).This paper deals with identification of the intruded salt-water wedge in the huge artesian Delta aquifer. The case is unique because most of this aquifer is invaded by salt water, and the major portion of its annual ground-water recharge is derived from the direct seepage from the Nile River and the huge net of irrigation canals serving about 3 million acres (∼ 11,561 km2) of fertile land, as well as the infiltration of excess irrigation water. The annual overall ground-water recharge to the aquifer was estimated as 6·40 km3/yr as explained later.Methods of salt-water control and various techniques of water resources management are discussed in this paper. Because of the great variation in the depth of the aquifer, two unconventional methods for identifying the salt-water wedge are also presented.

Notes: . Programs are presented for the HP41C and TI59 programmable calculators for determining the ratio of horizontal to vertical hydraulic conductivity in anisotropic confined aquifers from pumping test data or for calculating drawdown given the aquifer parameters. The programs, based on Hantush's drawdown equations (1961), eliminate the need to perform triple interpolation in obtaining the drawdown correction factor given in tabular form by Weeks (1969). The programs are illustrated by example.

Notes: A numerical model of flow and transport in the vicinity of Price's Landfill and the Atlantic City public water-supply wells is used to estimate the extent of the existing contamination problem. Model parameters such as boundary conditions, pumping rates, permeability, and dispersivity are varied to demonstrate the sensitivity of the model to these quantities. A historical simulation of the past ten years of contamination is obtained and two schemes for remediation of the contamination problem are compared. In the light of this work, additional data requirements are revealed.

Notes: Ion-exchange high performance liquid chromatography coupled with ultraviolet absorption detection is shown to be a rapid and sensitive method for analysis of some common anions in water. Sensitivity of measurement is approximately 50 ppb for NO−2, NO−3, Br−, I−, and SCN− while Cl− has a detection limit in the one to ten ppm range. Chromatograms require 8 to 13 minutes to complete. Analyses are performed on either of two stationary phases (Whatman SAX 10 μm or Brownlee anion exchange) depending on the anions of interest in the analysis and their interferences.

Notes: Vertical electrical soundings using DC resistivity methods have been completed along over 60 miles of survey lines in southwest Florida. The resistivity soundings were obtained in order to outline major hydrogeologic features as part of a regional hydrogeologic investigation covering approximately 400 square miles. The two significant hydrogeologic features which can be effectively mapped on a regional scale by DC methods are the presence of shallow, high resistivity limestones associated with late Tertiary reef complexes, and the approximate depth to waters with TDS concentrations well above the potable water limits. The reef limestones commonly exhibit very high transmissivities and are potential sites for ground-water development. The approximate thickness of potable waters allows resource investigations to be limited to the most promising areas and a rough assessment of the total resource to be made for long-term planning. The interpretation and mapping of the resistivity section is accomplished through published resistivity inversion and computer graphics programs. This automated data processing produces resistivity maps and sections without requiring extensive geophysical training of the interpreter. The automatic interpretations compare well with more traditional master curve interpretation procedures, and have the same limitations with equivalence of solutions and geologic correlation, but are produced with considerably less effort.

Notes: With an Apple II microcomputer it is possible to rapidly generate and graphically compare theoretical time-drawdown curves with field data from pumping tests in confined aquifers. This technique has the advantage over standard curve-matching methods in that any solution can be tested over the complete range of field data.

Notes: Entrenchment and subsequent filling of a glacial valley have led to localization of iron-enriched ground water in the Silurian carbonate aquifer at the Vistron plant, Lima, Ohio. All production wells are open exclusively to the carbonate aquifer. Water from the saturated glacial deposits of relatively low permeability and high ironcontent is drawn laterally into the more permeable carbonate aquifer containing water with relatively low concentrations of iron. Wells closest to the saturated glacial deposits yield water with iron concentrations greater than 1.4 milligrams per liter. These wells, in the southwestern part of the site, apparently form a sink preventing iron-enriched water from migrating into other pumping wells in the central and northern parts of the area.Iron concentrations have not increased in individual wells between 1971 and 1981. They are not expected to increase in the central and northern wells as long as about 20% of the plant's ground water is withdrawn from at least two of the southwestern wells.

Notes: Nitrate-N concentrations during the Summers of 1980 and 1981 exceeded 10 mg/1 in 68 of the 164 ground-water samples collected from a shallow water-table aquifer underlying a sand plain near Alliston, Ontario. Three extensive zones of nitrate contamination were associated with major potato-growing areas on the sand plain. Nitrate concentrations were positively correlated with both the percentage area of heavily fertilized crops (potatoes, corn, sod and asparagus) and nitrogen fertilizer application rates in the vicinity of ground-water sampling sites. Chloride levels in ground water exhibited a positive association with KCl fertilizer application rates. Ground water under potato fields had relatively consistent C1/NO3-N ratios despite considerable variations in nitrate-N and chloride concentrations. Ground water with a low nitrate content was found beneath forest and permanent pasture. These data suggest that the use of commercial nitrogen fertilizer is a major source of nitrate in the aquifer.

Notes: Abstract. A simple and convenient method for calculating two-dimensional dispersion on a TI 58 or 59 programmable calculator utilizing the normal distribution program available in the Solid State Software Master Library module as a subroutine is presented with an example.

Notes: Three simplistic models are developed for evaluating the transport of organic pollutants through soil to ground water. The models consider mobility and first-order degradation. The first calculates linear sorption/desorption of the pollutant and first-order degradation without considering dispersion. The second is similar to the first but also considers dispersion. The third considers nonlinear sorption following a Freundlich equation and first-order degradation but does not consider dispersion. The models are compared to field data for the pesticides aldicarb and DDT. The models projected a lower mobility for DDT than was observed in the field.

Notes: Darcy's equation and unsaturated-flow theory are used to calculate flow through earth linings that are placed in ponds or channels to reduce seepage. The procedure utilizes the relation between unsaturated hydraulic conductivity and pressure head of the underlying material as calculated from the measured saturated hydraulic conductivity and the relation between water content and pressure head. The method enables the selection of the liner (thickness and hydraulic conductivity) that will keep seepage below a certain maximum limit. Since the hydraulic conductivity of clays is affected by the cationic composition and the salt concentration of the soil solution, the chemical composition of the liquid moving through the liner must be taken into account. This applies also to other chemicals, including solvents and other organic compounds that may be in the water. Travel times of water from the surface impoundment to the underlying ground water are calculated from the seepage rate and the corresponding water content in the vadose zone. Accumulation of solids (mine tailings, for example) can further reduce the seepage from the pond. Proper design of waste-water ponds also requires analysis of the response of the underlying ground water (mound buildup) and the movement of pollutants in the vadose zone and aquifer. In view of the high costs of earth liners, prediction of the seepage is necessary to make sure that the selected lining material, the thickness of the liner itself, and the method of construction will produce the desired results.

Notes: A multidimensional, finite-difference model for ground-water flow and heat transport is used to analyze the thermal energy storage experiment conducted by Auburn University in Mobile, Alabama. The experiment consisted of three stages–namely, injection, storage and recovery occurring for 80, 51 and 41 days, respectively. This application demonstrates the validation evidence that the model adequately and accurately simulates the field experiment. The numerical model includes the effects of: hydraulic anisotropy, thermal convection and conduction, and heat loss to the adjacent confining strata. Observed aquifer isotherms at the end of each stage are compared with predicted values on a cylindrical grid situated about the well. The degree of vertical discretization used in the model is shown to impact the predicted temperature profiles at each stage, but has minimal effect on the recovery water temperature.

Notes: The author has used the concept of depression cone volume to derive type curve equations for large-diameter wells in aquifers of finite extent. Comparisons with the corresponding type curves in an infinitely extensive aquifer have been given. These solutions are based on joint exploitation of the ground-water movement equation (Darcy's law) and the continuity equation for large-diameter wells.

Notes: The majority of well fields in the river region in the Netherlands, where anaerobic water is withdrawn from the shallow aquifer, have problems with well clogging. In order to test the supposition that sulfate-reducing bacteria play a role in this clogging process, sulfate-reducing bacteria in water from wells on well fields with and without the occurrence of clogging were enumerated. In water withdrawn from nonclogging wells, the Most Probable Number of sulfate-reducing bacteria averaged 5 per 100 ml, whereas in wells subject to clogging, the number averaged 25 per 100 ml. A statistical analysis by Wilcoxon's order test confirmed that a significant difference exists between the numbers of sulfate-reducing bacteria in clogging and nonclogging wells. The mechanism whereby sulfate-reducing bacteria contribute towards this type of well clogging is as yet unclear.

Notes: The Kansas Geological Survey is pursuing an effort to automate some of the more common methods of aquifer pumping-test analysis. This paper discusses the results of work done on the leaky artesian aquifer as defined by Hantush and Jacob (1955). The paper covers the basic theory of the aquifer type, the numerical solution of the leaky artesian-well function, and the methodology of achieving the “best fit” parameters in the least squares' sense. Several data sets are used to demonstrate the applicability of the proposed technique. These examples indicate the generally satisfactory results produced by the automated analysis documented here.The algorithm has good convergence properties. Initial estimates for the aquifer parameters may vary by about three orders of magnitude above or below the correct values. For typical data sets the rms fitting error should be less than a few tenths of a foot. If this is not the case, one is probably not dealing with a simple leaky aquifer. This method of pumping-test analysis does not eliminate the role of an experienced hydrologist to define the local hydrogeology and aquifer type. However, once the decision is made as to which aquifer configuration is being observed, this program will, in a quick and unbiased fashion, give an accurate assessment of the leaky-aquifer parameters within the limits of the theoretical approximations and the data quality.