ALBERT

Notes: Many long-term contracts incorporate a termination clause. This paper argues that when agents have hidden information, such a clause has a beneficial incentive effect—it enables a principal to screen agents' private information at a lower cost. In a two-period model, this paper characterizes the optimal long-term contract with a termination clause, which specifies that the principal will switch agents in the second period when the first-period cost is high. The analysis delineates how the optimality of this clause depends on the intertemporal cost correlation structure, on the limits to agents' liability, and on the principal's degree of commitment.

Notes: Takeovers give raiders the opportunity of breaking implicit contracts inside the firm. If implicit contracts are adopted by workers and management to reach more efficient outcomes, then the possibility of takeovers may cause a welfare loss. We show that, under some conditions, this argument can go through even if the firm and the workers can write explicit and complete contracts. The crucial assumption is that the profitability of the firm is linked to its financial situation, in the sense that a firm which has a high probability of bankruptcy will face fewer opportunities than a financially solid firm. In this framework, the possibility of takeovers imposes constraints on the set of feasible employment contracts, leading to inefficient outcomes.

Notes: This paper deals with the strategic role of the temporal dimension of contracts in a duopoly market. Is it better for a firm to sign long-term incentive contracts with managers or short-term contracts? For the linear case, with strategic substitutes (complements) in the product market, the incentive variables are also strategic substitutes (complements). It is shown that a long-term contract makes a firm a leader in incentives, while a short-term contract makes it a follower. We find that, under Bertrand competition, in equilibrium one firm signs a long-term contract and the other firm short-term incentive contracts; however, under Cournot competition, the dominant strategy is to sign long-term incentive contracts.

Notes: Why is it so common for the seller to provide guarantees that say “Satisfaction guaranteed or your money back” along with the sale of a product? Newly introduced goods and mail-ordered products are usually sold with such guarantees. In honoring money-back guarantees, why is it a common business practice to pay back exactly the purchase price rather than a portion of it? In this paper we study the informational role and optimality of the common business practice of money-back guarantees in a signaling model with quality uncertainty and risk-neutral buyers. We find that money-back guarantees and price together completely reveal a monopoly firm's private information about product quality, Moreover, the private information is revealed at no signaling cost. Furthermore, we show that in terms of the level of monetary compensation specified by a guarantee, price is the profit-maximizing level of monetary payback in case of product failure.

Notes: Manufacturers may intentionally damage a portion of their goods in order to price discriminate. Many instances of this phenomenon are observed. It may result in a Pareto improvement.

Notes: It is generally believed that industries with greater product differentiation have higher rates of return. This paper shows that this effect breaks down in the presence of firm-specific cost shocks. Greater substitutability in products generates two opposing effects: (1) it allows a larger increase in demand when a firm has a favorable cost shock, which more than compensates for the reduction in demand when it has an unfavorable cost shock, and (2) it results in more intense price competition. These two countervailing forces result in industry profit being highest in markets with a moderate degree of product differentiation.

Notes: We present a model of industry evolution where the dynamics are driven by a process of endogenous innovations followed by subsequent embodiments in physical capital. Traditionally, the only distinction between R&D and physical investment was one of labeling: the first process accumulates an intangible stock, knowledge, while the second accumulates physical capital. Both stocks affect output in a symmetric fashion. We argue that the story is not that simple, and that there is more to it than differences in the object of accumulation. Our model stresses the causal relationship between past R&D expenditures and current investments in machinery and equipment. This causality pattern, which is supported by the data, also explains the observed higher volatility of physical investment relative to that of R&D expenditures.

Notes: We examine the question of whether a regulated firm that makes a long-term investment in infrastructure can credibly signal its private information regarding the future demand for its output to the capital market. We show that necessary conditions for a separating equilibrium in which the magnitude of investment signals high future demand may include a low degree of managerial myopia, large variability of future demand, a lenient regulatory climate, and low sunk cost. Our model suggests that in estimating valuation models of regulated firms it is important to separate firms into two groups: firms for which a separating equilibrium is likely to obtain and firms for which the equilibrium is likely to be pooling. The market value of a firm in the first group is positively correlated with its level of investment, but uncorrelated with the level of actual demand, whereas for the second group the opposite holds.

Notes: This paper develops the hypothesis that firms possess a stock of well-established brands, a stock termed brand capital. The firm with the greatest capital is able to introduce new products in response to new information about consumer tastes before rivals. The results using data from the ready-to-eat cereal industry not only support this hypothesis, but also distinguish brand capital from other sources of firm heterogeneity.

Notes: This paper attacks the problem of developing strategies for a firm to deal with technological change. We show that the product market strategies of the firm—including pricing, product positioning, and rent preemption strategies—can play a role in the efficient search for technology-related information when information search is costly and there are adaptation costs due to the presence of agency. We utilize a dynamic model of spatial competition with uncertain technological innovations in which firms can learn from each other about technological developments. Private information and agency conflicts are shown to increase the effective information search costs of incumbents, who then use interfirm learning to their advantage in equilibrium. This viewpoint also allows us to see the role of mergers and acquisitions, subsidiary formation, and internal R&D labs in a new light. The more general point is that organizational structures and, in particular, the differential distribution of information within the organization impose constraints on the information-search and adaptation strategies of the firm, and the formulation of product-market and R&D strategies serves to relax these constraints.

Notes: The paper studies managerial incentives in a model where managers choose product market strategies and make takeover decisions. The equilibrium contract includes an incentive to increase the firm's sales, under either quantity or price Competition. This result contrasts with previous findings in the literature, and hinges on the fact that when managers are more aggressive, rival firms earn lower profits and thus are willing to sell out at a lower price. However, as a side effect of such a contract, the manager might undertake unprofitable takeovers.

Notes: For U.S. futures exchanges, controlling costs while maintaining market performance is an ongoing, difficult challenge. New market realities have made that challenge even more daunting in recent years as costs have escalated, competition has expanded, and the role of information technology has expanded. It is always difficult for regulatory statutes to keep pace with ever-changing markets. Futures markets are no exception. The basic statutory framework represented by the Commodity Exchange Act (CEA) was enacted in 1922, over seventy years ago. In order to maintain appropriate regulatory balance, periodic review and reform has been essential over the years. Our current federal regulatory systems were built for different markets with different competitive realities than we face today. Reforming the CEA to take into account those new market realities is vital to the survival of U.S. futures exchanges.

Notes: We develop a game-theoretic version of the right-to-manage model of firm-level bargaining where strategic interactions among firms are explicitly recognized. Our main aim is to investigate how equilibrium wages and employment react to changes in various labor and product market variables. We show that our comparative statics results hinge crucially on the strategic nature of the game, which in turn is determined by the relative bargaining power of unions and managers.

Notes: We develop a simple model in which there is both interfirm (or intraproduct) and intrafirm (or interproduct) competition. The purpose is to develop a classificatoy framework in order to understand product-range or diversification decisions alongside conventional competition. The equilibrium outcomes commonly involve a limited range of the available goods being produced. Deterrence equilibria and other strategic actions are also examined.

Notes: DeGraba and Postlewaite (1992) show that the seller of a durable input can solve the time inconsistency problem by offering most-favored-customer (MFC) protection to buyers. McAfee and Schwartz (1994) show that if a supplier sells inputs to competing firms using two-part tariffs, MFC protection that allows a firm to replace its contract with a contract executed by any other firm will not solve the commitment problem, and argue this implies managers cannot use MFCs as a strategic commitment device in complex contracting situations. This paper shows that if the profits of the seller and the buyers are monotonic in each term of the contract, then applying MFC protection to each term of a contract allows a manager to solve his commitment problem in complex contacting situations. We show that “standard” contract arrangements (two-part tariffs, declining block tariffs, and royalties as a percentage of sales) meet this condition.

Notes: This paper develops a theory of capital structure based on the attempts of a firm to alleviate a holdup problem that arises in its bilateral relationship with a buyer. It is shown that by issuing debt to outsiders, the firm can improve its ex post bargaining position vis-a-vis the buyer and capture a larger share of the ex post gains from trade. Debt, however, is costly because the buyer may find the required price too high and refuse to trade. Since debt raises the payoff of claimholders, it strengthens the firm's incentive to make relationship-specific investments, and therefore alleviates the well-known underinvestment problem. A comparative static analysis yields a number of testable hypotheses regarding the firm's financial strategy.

Notes: Whether vertical integration between a downstream oligopolist and an upstream oligopolist is profitable for an integrated pair of firms is shown to depend on whether one means by this that profits increase no matter what other firms do, that all integrated firms are better off when all firms are integrated than when none are, or simply that no downstream-upstream pair of firms has an incentive to deviate from a situation where all firms are integrated. It is also shown to depend on the number of firms in each oligopoly and on the type of interaction that is assumed between firms that are integrated and firms that are not. In particular, it is shown that if no restriction is put on trade between integrated and nonintegrated firms, integrated firms may continue to purchase inputs from the nonintegrated upstream firms, with the goal of raising their downstream rivals' costs. Furthermore, even though firms are identical, asymmetric equilibria, where integrated and nonintegrated firms coexist, may actually arise as an outcome of the integration game.

Notes: This paper considers the incentives of a firm with power in a market for one good to tie in the sale of a complementary good even though the complementary good is produced in a zero profit market. If the zero-profit price of the tied good is greater than the marginal cost (which occurs for example when the technology is characterized by a fixed cost and a constant marginal cost), a firm will fie in order to increase the sales of the complementary good, which at the margin is profitable. We show that such tying will lower the effective prices paid by customers and increase welfare. This incentive exists if the firm with market power is a monopolist or one of several competing oligopolists.

Notes: This paper examines the effect of a middleman on the search and trading behavior of the traders. It is shown that the buyer and seller types with middle valuations choose to search for each other, while the buyer and seller types with high or low valuations drop out of the search market and choose to trade directly with the middleman. The ask and bid prices of the middleman act as an outside option for the buyer and seller, and influence the outcome of the bargaining between the two. The model generalizes Gehrig (1993) by endogenizing the traders' search intensities, by allowing the traders to go to an intermediary even if thy have engaged in search, and by enabling the intermediary to provide the service of immediacy.

Notes: This paper discusses the supplier power of medical specialists. We argue that a combination of factors, including the structure of health care delivery, reimbursement systems, the presence of option demand, and high consumer switching costs, create circumstances in which medical specialists may be able to exercise significant seller power. We explore the implications of this for the pricing and organization of medical care.

Notes: This paper offers an exact definition of the value created by firms together with their suppliers and buyers. The “added value” of a firm is similarly defined, and shown under certain conditions to impose an upper bound on how much value the firm can capture. The key to a firm's achieving a positive added value is the existence of asymmetries between the firm and other firms. The paper identifies four routes (“value-based” strategies) that lead to the creation of such asymmetries. Our analysis reveals the equal importance of a firm's supplier and buyer relations. Cooperative game theory provides the underpinnings of the analysis.

Notes: The recent emergence of total quality management (TQM) in the U.S. has spawned a great deal of interest in management circles as well as in the mass media. However, despite the growing number of firms that have adopted this management technique, few formal tests exist concerning the pattern of adoption as well as the changes that accompany the adoption of TQM. This paper contrasts models of production for TQM and non-TQM firms in order to explore reasons why some firms but not others have adopted the TQM approach to quality improvement. Predictions arising from such a comparison are tested using a unique data set that combines data on firms from three different sources. Our findings tend to support the proposed theory of systematic differences between firms that find it advantageous to adopt TQM and firms that do not. We also find evidence that firms adopting TQM experience greater growth in sales, employment, and capital stock.

Notes: Duopolistic interaction between a small firm and a large established firm is considered and compared to guerrilla warfare, The paper investigates a “hit and run” equilibrium in which the small firm enters the market, stays there for several periods, exits, stays out for several periods, and then reenters. Occasionally there may be a price war (or retaliation), but the small firm may also exit voluntarily, thereby avoiding possible confrontation. The amount of time that the small firm stays in the market and the timing of the price wars do not follow any predictable pattern, which is part of the mixed strategies that both firms play in equilibrium.

Notes: I investigate how different sources of information influence the diffusion of pharmaceutical innovations. In prescription-drug markets, both advertising and scientific information stemming from clinical trials can affect physicians' prescription choices. Using novel indices of clinical-research output, I find that both marketing and scientific evidence directly influence the diffusion process in the antiulcer-drug market, with marketing having a more pronounced influence. I also find evidence that clinical outputs are important drivers of firms' marketing efforts, affecting sales indirectly. Taken together, the direct and indirect effects of science on demand imply strong private incentives for clinical research. I conclude that product-market competition in the pharmaceutical industry is shaped by both advertising rivalries and scientific rivalries. Moreover, drug advertising may perform an important informative function.

Notes: The paper studies the effects of bundling on the bidding strategies and seller revenues in auctions when the bidders have common values for the objects. Bundling of objects before the auction reduces the problem of the winner's curse, and the bidders bid more aggressively. This does not mean that a bundled auction is always better for the seller's revenue. Indeed, there is another effect that makes the bundled auction preferable (from the seller's standpoint) if and only if the number of bidders is small. While this is the only effect present in an independent-private-values model, it does not vanish when bidders have pure common values for the objects. The paper concludes that a bundled auction is unambiguously better for the seller than separate auctions when the number of bidders is small.

Notes: There are a growing body of theoretical work, wide anecdotal evidence, and a few large-scale empirical studies supporting the view that business firms quite rarely change their organizational structure, a phenomenon usually referred to in the literature as structural inertia. The present paper aims to analyze empirically the determinants of structural inertia and organizational change. As far as we know, this work constitutes the first attempt to directly address such issues through econometric estimates based on a large, longitudinal dataset at plant level. For this purpose, we consider changes of the organizational structure within a sample composed of 438 Italian manufacturing plants observed from 1975 to 1996. More precisely, we specify and test a duration model of the likelihood of an individual plant changing the number of hierarchical tiers after a spell r, provided that no change has occurred up to T. We also analyze the direction of change, distinguishing increases from decreases of the number of managerial layers. We consider a set of plant- and industry-specific explanatory variables that are expected to induce or oppose organizational change. The findings show that the adoption of advanced manufacturing technologies and new human-resources management practices favors organizational change. On the contrary, the presence of sunk costs and the extent of influence activities figure prominently in explaining structural inertia of business organizations.

Notes: A simple model of open source software (as typified by the GNU-Linux operating system) is presented. Individual user-programmers decide whether to invest their own effort to develop a software enhancement that will become a public good if so developed. The effect of changing the population size of user-programmers is considered; finite and asymptotic results are given. Welfare results are presented. It is shown that whether development will increase when applications have a modular structure depends on whether the developer base exceeds a critical size. Potential explanations of several stylized facts are given, including why certain useful programs don't get written.

Notes: This paper examines the effect of memory loss on the continuity of behavior. We consider a player (individual or firm) who remembers previous actions but not underlying rationales. In a stable environment, relative to a full-recall scenario, memory loss increases the probability of following old policies (inertia). In a volatile environment, memory loss can decrease this probability (impulsiveness). The model provides a memory-loss explanation for some documented psychological biases, implies that inertia and organizational routines should be more important in stable environments than in volatile ones, and provides empirical implications relating memory and environmental variables to economic decisions.

Notes: Syndication arises when venture capitalists jointly invest in projects. We model and test two possible reasons for syndication: project selection, as an additional venture capitalist provides an informative second opinion; and complementary management skills of additional venture capitalists. The central question is whether venture capitalists are engaged primarily in selection or in managerial value added. These alternatives imply contrasting predictions about comparative returns to syndicated and standalone investments. Our empirical analysis, using Canadian data, finds that syndicated investments have higher returns, favoring the value-added interpretation. We also discuss risk sharing and project scale as possible reasons for syndication.

Notes: In the context of an employment relationship, I present an argument suggesting that it is more efficient for the boss to own the productive assets. The idea is that a conflict between productivity and depreciation is internalized if the player deciding what an asset is used for also has residual claims. An empirical test finds evidence consistent with this. By asking whether the boss should own the assets, the paper reverses the reasoning from the literature in which it is argued that the owner has power and thus is the boss.

Notes: Cooperative equilibria can be supported in a repeated game when players use trigger strategies. This paper tests how well trigger strategies explain behavior in two-person experimental games. Reducing payoffs for choices larger than the Cournot level induces smaller average outputs, behavior generally consistent with trigger strategy models. Reducing payoffs for choices well above the Cournot level will not affect behavior if actions are consistent with a trigger strategy involving longer-lived, less intense punishment phases (the grim-reaper strategy), but would matter for trigger strategies with short-lived but intense punishment phases. Results show that behavior is most consistent with the former.

Notes: Knickerbocker (1973) introduced the notion of oligopolistic reaction to explain why firms follow rivals into foreign markets. We develop a model that incorporates central features of Knickerbocker's story—oligopoly, uncertainty, and risk aversion—to establish the conditions required to generate follow-the-leader behavior. We find that rival foreign investment will make risk-neutral firms less inclined to move abroad once its rivals have done so. We show that Knickerbocker's prediction relies on risk aversion and derive an expression for the minimum amount of risk aversion needed to generate oligopolistic reaction.

Notes: Horizontal mergers between firms that have different costs are examined. Owners can transfer technology to an acquired firm and decide whether to consolidate or operate their firms as separate entities in the product market. Thus mergers can exhibit both efficiencies and a market-power effect. The prices of target firms are determined via a bargaining game. An equilibrium sequence of mergers entails the largest firm targeting the next largest rival firm. Initially, this sequence of mergers with technology transfers involves no consolidations and improves welfare. Ultimately, the acquisitions lead to consolidation and may decrease total welfare.

Notes: This note corrects Proposition 3 of Chang (1998).

Notes: It is often claimed that (i) managers work too hard on operational issues and do not spend enough effort on strategic activities, and (ii) something can be done about this by introducing nonfinancial performance measures, as for instance with a balanced scorecard. We give an explanation for both claims in a formal model. The distortion toward operational effort arises because with financial performance measures strategic effort can only be rewarded in the future. But renegotiation-proof long-term compensation plans entail too weak variable components in the future. This problem can be reduced by introducing performance measures that help to disentangle strategic and operational effects.

Notes: Central to so many accounts of post-war Japan, the keiretsu corporate groups lacked economic substance from the start. Conceived by Marxists committed to locating “domination” by “monopoly capital,” they found an early audience among western scholars searching for evidence of culture-specific group behavior in Japan. By the 1990s, they had moved into mainstream economic studies, and keiretsu dummies appeared in virtually all econometric regressions of Japanese industrial or financial structure. Yet the keiretsu began as a figment of the academic imagination, and they remain that today. Regardless of the keiretsu definition used, cross-shareholdings within the “groups” were trivial, even during the years when keiretsu ties were supposedly strongest. Neither does membership proxy for “main bank” ties. Econometric studies basing “keiretsu dummies” on the available rosters produce predictably haphazard and unstable results. In the end, the only reliably robust results are the artifacts of the sample biases created by the definitions themselves.

Notes: We use survey data and field research to investigate the effects of employee involvement practices on outcomes for blue-collar workers in the auto-supply industry. We find these practices raise wages by 3–5%. The causal mechanism linking involvement and wages appears to be most consistent with efficiency-wage theories, and least consistent with compensating differences. We find no evidence that employee involvement affects plants' survival or employment growth.

Notes: The modern corporation is characterized both by a separation of ownership from management and by managerial incentives that often include strategic elements in addition to the standard incentive elements. Despite the importance of these two features in the agency and corporate-governance literatures, they are absent in the treatment of the firm in the patent-licensing literature. The analysis in this paper shows how, by simply taking into account these two features of the modern corporation, it is possible to offer a new explanation for the use of royalties in licensing agreements.

Notes: This paper introduces a theory of network incentives in managed health care. Participation in the plan's network confers an economic benefit on providers; in exchange, the plan expects compliance with its protocols. The network sets a target for the number of outpatient visits in an episode of care. A provider failing to satisfy the target may be penalized by the plan's attempt to direct patients to other providers within its network. There is an equilibrium in which every provider in the network uses the target. We test the theory by observing behavior of providers before and after the introduction of managed mental health care in a large, employed population. Managed care consisted of price reductions, utilization review, and creation of a network. Quantity per episode of care fell sharply after initiation of managed care. We identify a network effect in our empirical work. The results indicate that in this case, network incentives account for most of the quantity reduction due to managed care.

Notes: In this field-based study, we interview top- and middle-level managers at Insteel Industries and conduct statistical analysis of firm-level data in order to shed light on whether activity-based costing (ABC) provides new information to managers and whether activity-based management (ABM) significantly influences product and customer-related decisions. We find that after the ABC analysis, Insteel undertook a number of process improvements that resulted in significant cost savings. Additionally, Insteel displayed a higher propensity to discontinue or increase prices of products and discontinue customers that were found comparatively unprofitable in the ABC study. Thus we provide empirical evidence that ABC influences both strategic and operational managerial decisions.

Notes: Managed care organizations control costs through restrictions on patient access to specialized services, oversight of treatment protocols, and financial incentives for providers. We investigate possible effects of such practices on the care patients receive by studying frequencies of in-hospital complications. We find significant differences in complication rates between managed care and fee-for-service patients. We investigate the sources of this variation by comparing probabilities of complications among patients with different types of managed care coverage and patients treated in different hospitals. For several patient categories, the differences in outcomes we find appear to arise not from differential treatment of patients within hospitals or from heterogeneity in patients, but from variations in care across hospitals that tend to treat patients with different insurance types.

Notes: One of the mechanisms that are implemented in the cost containment movement in the health care sectors in western countries is the definition, by the third-party payer, of a set of preferred providers. The insured patients have different access rules to such providers when ill. The rules specify the copayments patients must pay when using an out-of-plan care provider. This paper studies the competitive process among providers in terms of both prices and qualities. Competition is influenced by the status of providers as in-plan or out-of-plan care providers. Also, there is a moral hazard of provider choice related to the trade-off between freedom to choose and the need to hold down costs. It is possible to achieve the first-best allocation by an appropriate definition of the reimbursement scheme when decisions on prices and qualities are taken simultaneously (as in primary health care sectors). In contrast, some type of regulation is needed to achieve the optimal solution when decisions are sequential (as in specialized health care sectors). We also derive normative conclusions on how price controls should be implemented in some European Union member states.

Notes: If an illness is not contractible, then even partially insured consumers demand treatment for it when the benefit is less than the cost, a condition known as moral hazard. Traditional health insurance, which controls moral hazard with copayments (demand management), can result in either a deficient or an excessive provision of treatment relative to ideal insurance. In particular, treatment for a low-probability illness is deficient if illness per se has little effect on the consumer's marginal utility of income and if the consumer's price elasticity of expected demand for treatment is large relative to the risk-spreading distortion when these are evaluated at a copayment that brings forth the ideal provision of treatment. Managed care, which controls moral hazard with physician incentives, can either increase or decrease treatment delivery relative to traditional insurance, depending on whether demand management results in deficient or excessive treatment.

Notes: This paper asserts that brand pharmaceutical firms (those mostly involved in the invention and production of new drugs) engage in a set of complementary activities that are different from those of generic pharmaceutical firms (those that primarily make off-patent medicines). Complementarities of the Milgrom-Roberts variety within, but not across, these two kinds of firms make it more efficient for pharmaceutical firms to specialize in either brand or generic production. Using FDA data, I show that this is indeed the case. I then examine the firms that produce both types of drugs to see if there are market-level strategic synergies between brand and generic products. I find generic entrants that belong to a corporation that owns the brand in the market are (1) not more likely to enter, (2) not more likely to be approved faster, and (3) not more likely to deter other generics from entering. Thus the advantage, or synergy, from mixing brand and generic activities in one corporation must arise elsewhere in the operations of the firm. If not, the integrated pharmaceutical firm is not the most efficient organizational form for the production of ethical drugs.

Notes: A panel of speakers, knowledgeable in the problems of photogrammetry in the Third World, led a discussion which considered the place of sophisticated photogrammetric equipment in the Third World, problems of technician and management training, the desire for self reliance, and the needs of map revision.〈section xml:id="abs1-2"〉〈title type="main"〉RésuméUne confrontation entre photogrammètres sur le sujet photogrammétrie et tiers-monde; équipement, instruction des techniciens, problèmes d'organisation, désir d'autonomie, révision des cartes.〈section xml:id="abs1-3"〉〈title type="main"〉ZusammenfassungEin Forum von Kennern der Probleme der Dritten Welt führte eine Diskussion über den Platz moderner Geräteausrüstungen in diesen Ländern, über Probleme der Ausbildung von Technikern und Führungskadern und erörterte den Wunsch nach Selbstbestätigung und die Notwendigkeit zur Laufendhaltung von Karten.

Notes: The problems associated with the depiction of a particular irrigation area by both line map and orthophotomap are described and the results compared.〈section xml:id="abs1-2"〉〈title type="main"〉RésuméDes problèmes soulevés par la description d'une aire d'irrigation à l'aide d'une carte ou d'une ortho-photocarte: comparaison des résultats.〈section xml:id="abs1-3"〉〈title type="main"〉ZusammenfassungBeschreibung der Probleme, die bei Auswahl sines Bewässerungsgebietes an Hand von Strich- und Orthophotokarten auftraten und Vergleich der Ergebnisse.

Notes: In 1981, a metric camera will be launched into space on a European Space Agency Spacelab mission. This paper examines the specification for this mission and the expected results. Other developments are also considered. These include the American large format camera and long focal length imaging systems.〈section xml:id="abs1-2"〉〈title type="main"〉RésuméEn 1981, une chambre métrique sera lancée dans l'espace (mission Spacelab de l'organisation européenne spatiale). On examine ici les buts et les résultats attendus, ainsi que de futurs développements; chambre américaine à grand format, systèmes à longues focales.〈section xml:id="abs1-3"〉〈title type="main"〉ZusammenfassungIm Jahre 1981 soll sich an Bord des Europäischen Spacelab-Satelliten eine Messkammer befinden. Im Artikel werden die Anforderungen an dieses Projekt und die zu erwartenden Ergebnisse diskutiert. Desgleichen werden auch andere Entwicklungen, worunter sich die amerikanische Grossformat-Kammer und langbrennweitige Systeme befinden, erörtert.

Notes: Many attempts have been made to use various types of photography for traffic studies. The problems most frequently encountered are the expense involved in obtaining the photography and the time consuming and, hence, expensive operation of collecting the required data from the photography. This paper discusses the problems associated with various types of photography and describes a study which has been carried out to evaluate the potential of 16 mm and 35 mm time lapse photography taken from a helicopter. The accuracy of two dimensional co-ordinate transformation systems for collecting the required data from the photography is also described. Finally, recommendations are made regarding the most suitable type of photography and the most convenient and accurate transformation system to use when it is required to analyse the traffic flow data at complex urban and suburban intersections.〈section xml:id="abs1-2"〉〈title type="main"〉RésuméBeaucoup de tentatives ont déjàété faites pour étudier les problèmes de circulation par photographie: les difficultés sont le coût de la photographie, les délais d'obtention et le coût du dépouillement. On examine ici les possibilités offertes par divers types de photographies et on donne les résultats d'une étude entreprise pour évaluer l'intérêt de la solution; camera 16 mm ou 35 mm plus hélicoptère. On précise ici l'exactitude requise pour les transformations de coordonnées. On conclut par toute une série de recommandations.〈section xml:id="abs1-3"〉〈title type="main"〉ZusammenfassungEs gibt sehr viele Versuche zur Verwendung verschiedener Arten der Photographie für Verkehrsstudien. Die am häufigsten auftretenden Probleme sind die Kosten und der Zeitaufwand der Photographie, wodurch die Datenerfassung aus Photos teuer wird. Im Artikel werden die Probleme beschrieben, die bei Anwendung verschiedener photographischer Aufnahmen auftraten. Ferner wird ein Versuch mit 16 mm und 35 mm Zeitrafferaufnahmen aus dem Hubschrauber erörtert. Beschreibung der Genauigkeit zweidimensionaler Koordinatentransformationen zur Ermittlung der gewünschten Daten aus Photos. Abschliessend werden Empfehlungen bezüglich der am besten geeigneten photographischen Methode und zur Transformation der Daten gegeben, wenn Verkehrsströme an komplexen Kreuzungen in Städten und Vororten analysiert werden sollen.

Notes: On 17th January, 1978, the Secretary of State for the Environment announced the establishment of a Committee, chaired by Sir David Serpell, with the following terms of reference: “Taking account of the views of users and other interested parties, in the context of national surveying and mapping needs, to consider and make recommendations about the longer term policies and activities of the Ordnance Survey and ways of financing them.” Interested organisations, among them The Photogrammetric Society, were invited to submit evidence to the Committee. The Society's submission is reproduced in full. The Secretary of State has asked the Committee to report, if possible, early in 1979.〈section xml:id="abs1-2"〉〈title type="main"〉SummaryAs has been stated the national survey, comprising as it does the horizontal and vertical control frameworks and the basic scales mapping based upon it, represents (assuming completion of the last named) a priceless national asset, but it is not “money in the bank”. It is an ephemeral and fragile asset which will have been frittered away unless it is constantly maintained, repaired and refurbished; even so it will not last forever. At one time or another the various components will all require replacement eventually. What must be avoided at all costs is a repetition of such culpable neglect that it all needs replacement at the same time. This summarises what is now, and must remain, the prime objective of the Ordnance Survey. Superimposed upon this are the needs to make the survey available, in various forms, to users; to produce small scale mapping; and to collect and disseminate various other forms of topographic data.〈section xml:id="abs1-3"〉〈title type="main"〉Résumé Le 17 Janvier 1978, le secrétaire d'Etat à l'environnement anonçait la création d'une commission, présidée par Sir David Serpell: les objectifs étant précisés de la manière suivante; “Tenant compte des besoins des utilisateurs et des autres parties intéressées aux activités cartographiques, proposer une orientation à long terme de la politique de l'établissement et revoir les modes de financement de l'Ordnance Survey.”Les organisations concernées, et parmi elles la Photogrammetric Society, étaient invitées à entrer en relation avec la commission: on reproduit ici in extenso la déposition de la Photogrammetric Society. Le secrétaire d'Etat a demandéà la commission de remettre son rapport début 1979 si possible.〈section xml:id="abs1-4"〉〈title type="main"〉Zusammenfassung Am 17.1.1978 kündigte der Staatssekretär für Umweltfragen die Gründung eines Komitees unter Vorsitz von Sir David Serpell an, dasfolgende Aufgabe erfüllen soll: “Analyse der Ansichten von Nutzern und anderen interessierten Gruppen bezüglich der nationalen Anforderungen an Vermessungswesen und Kartographie, um daraus Empfehlungen für die längerfristigen Aktivitäten des Ordnance Survey und die Möglichkeiten zur Finanzitrung abzuleiten.” Interessierte Organisationen, darunter die Photogrammetric Society, wurden eingeladen, die Tätigkeit des Komitees zu unterstützen. Für Anfang 1979 soll ein Bericht vorgelegt werden.

Notes: Professor F. Ackermann was specially invited to contribute an article to mark the 50th issue of The Photogrammetric Record. As the only photogrammetrist to have received both the Brock and von Gruber awards of the International Society for Photogrammetry, he is particularly well qualified to express his views on the past and future development of photogrammetry.〈section xml:id="abs1-2"〉〈title type="main"〉RésuméLe professeur Ackermann a été invitéàécrire un article pour fêter la sortie du 50ème numéro. Seul photogrammètre cumulant médaille de Brock et médaille de von Gruber, il était particulièrement qualifié pour juger du passé et préjuger de l'avenir de la photogrammétrie.〈section xml:id="abs1-3"〉〈title type="main"〉Zusammenfassung Professor Ackermann wurde gezielt eingeladen, um einen Beitrag anlässlich des Erscheinens der 50. Ausgabe des Photogrammetric Record beizusteuern. Als einziger Photogrammeter, der sowohl den Brock- als auch v. Gruber-Preis der ISP erhalten hat, ist er besonders qualifiziert, seine Ansichten über Vergangenheit und Zukunft der Photogrammetrie zu äussern.

Notes: The author describes his experiences of working with Professor E. H. Thompson on the design and construction of the Thompson-Watts plotter and he relates several anecdotes of incidents which took place at the Hilger and Watts factory.〈section xml:id="abs1-2"〉〈title type="main"〉RésuméOù on décrit l'expérience d'années passées à travailler avec le professeur Thompson sur le projet du restituteur Thompson- Watts avec de nombreuses anecdotes sur la vie à l'usine Hilger and Watts.〈section xml:id="abs1-3"〉〈title type="main"〉ZusammenfassungDer Autor schreibt über seine Erfahrungen, die er bei der Zusammenarbeit mit Professor E. H. Thompson beim Entwurf und der Konstruktion des Thompson–Watts-Plotters sammelte. Er erwähnt dabei einige Anekdoten über Vorfälle, die sich bei der Firma Hilger und Watts ereigneten.

Notes: A history and analysis of stereoplotting instrument design and construction in the United Kingdom is given, beginning with the earliest instruments of F. V. Thompson dating from 1907 and 1908 and covering all known designs up till the late 1960s. In the first part of the paper, the instruments built in the 1920s and 1930s are described, much new information having come to light recently in the archives of Ban and Stroud Ltd. and in the papers of the late Professor E. H. Thompson. In the second part of the paper, the instruments which were produced during and after the Second World War are discussed in detail, with an emphasis on those designs which are less well known rather than those which were produced in quantity. The ideas and designs of Deville, F. V. Thompson, Fourcade and E. H. Thompson have been the dominating influences throughout the period and a strong thread of continuity can be established between them.〈section xml:id="abs1-2"〉〈title type="main"〉RésuméOn fait l'histoire du restituteur analogique en Grande Bretagne, depuis ses balbutiements (F. V. Thompson 1907–1908), jusq'aux années 60. On décrit en particulier les appareils conçus dans les années 20 et 30, en tenant compte d'une masse d'informations inconnues à ce jour tirées des archives de M. Barr et Stroud, et de celles de feu le professeur Thompson. Puis on passe à ceux qui ont été produits pendant et après la guerre, en s'attachant surtout à ceux qui sont moins connus parce que n'ayant pas été produits en série. Ce sont les idées et projets de Deville, F. V. Thompson, Fourcade et E. H. Thompson qui ont dominé cette période, et le fil qui les relie reste très perceptible.〈section xml:id="abs1-3"〉〈title type="main"〉ZusammenfassungEs wird ein Überblick und eine Analyse über den Entwurf und die Konstruktion von Stereoauswertegeräten im Vereinigten Königreich gegeben, wobei der Autor, beginnend mit den ersten Geräten von F. V. Thompson aus den Jahren 1907 und 1908 alle bekannten Entwürfe bis Ende der 60iger Jahre behandelt. Im 1. Teil werden die Geräte der 20iger und 30iger Jahre beschrieben, wobei viel neue Informationen aus dem Archiv der Firma Barr und Stroud und den Beiträgen des verstorbenen Professor E. H. Thompson entstammen. Im 2. Teil werden die während des 2. Weltkrieges und danach produzierten Geräte diskutiert, wobeisolche hervorgehoben werden, die weniger bekannt wurden als die in grossen Stückzahlen produzierten. Die Ideen und Entwürfe von Deville, F. V. Thompson, Fourcade, E. H. Thompson hatten einen bedeutenden Einfluss während dieser Zeit, und es kann eine starke kontinuierliche Verbindung zwischen ihnen aufgezeigt werden.

Notes: 18th International Symposium of Cipa by D. M. Barber, p.50548th Photogrammetric Week by A. T. Smart, p.5065th Conference on Optical 3D Measurement Techniques by G. Hunter, p.509

Notes: Book review in this ArticleTHE UNITED KINGDOM FROM SPACE (2). By D. J. Carter and H. J. P. Arnold. Space Frontiers Ltd. Havant, Hampshire, 1977.SURVEYS FOR DEVELOPMENT. Edited by J. J. Nossin. Elsevier Scientific Publishing Co. Amsterdam, Oxford, New York, 1977.REMOTE SENSING OF THE TERRESTRIAL ENVIRONMENT. Edited by R. F. Peel, L. F. Curtis and E. C. Barrett. Butterworths, London, 1977.MAPPING FOR FIELD SCIENTISTS. By W. Ritchie, D. A. Tait, M. Wood and R. Wright. David and Charles, Newton Abbot, Devon, 1977.SURVEYING AND PHOTOGRAMMETRY. COMPUTATION FOR CIVIL ENGINEERS. By D. E. Murchison. Newnes–Butterworths, London, 1977.RESOURCE SENSING FROM SPACE: PROSPECTS FOR DEVELOPING COUNTRIES. Report of the Ad Hoc Committee on Remote Sensing for Development. US National Academy of Sciences, Washington, D.C., 1977.MISSION TO EARTH: LANDSAT VIEWS THE WORLD. By N. M. Short, P. D. Lowman, S. C. Freden and W. A. Finch. National Aeronautics and Space Administration, Washington, D.C., 1976.REMOTE SENSING IN GEOMORPHOLOGY. By H. Th. Verstappen. Elsevier Scientific Publishing Company, Amsterdam, Oxford, New York, 1977.

Notes: The development of remote sensing techniques for land use studies is briefly reviewed and some problems of interpretation of aerial and satellite photography considered. The need for a ground based data collection system is indicated and a prototype system developed at the University of Bristol is described. Some preliminary results obtained with this system are presented.〈section xml:id="abs1-2"〉〈title type="main"〉RésuméOn passe en revue les progrès des techniques de télédétection en matière d'étude des sols et on examine certains problèmes d'interprétation des photographies aériennes et satellitaires. On insiste sur la nécessite d'établir une banque de données pour l'interprétation; on décrit le prototype qu'on met au point à l'université de Bristol, et certains résultats qu'il a déjà permis d'obtenir.〈section xml:id="abs1-3"〉〈title type="main"〉ZusammenfassungDie Entwicklung der Fernerkundungsverfahren für Landnutzungsstudien wird kurz eingeschätzt und einige Probleme der Interpretation von Luftbildern und Satellitenphotos werden analysiert. Dabei wird die Notwendigkeit zur Schaffung eines Datenerfassungssystems im Gelände aufgezeigt und ein Prototyp eines solchen Systems, das an der Universität Bristol entwickelt wurde, beschrieben. Einige hiermit erhaltene vorläufige Ergebnisse werden angegeben.

Notes: The Photogrammetric Society was formed in 1952. The Council of the Society considered that the twentieth anniversary was a good point at which to record the events which led to its formation and the significant occasions and decisions which have taken place since 1952. Consequently, Paul Lamboit was invited to compile this History. He has placed the birth and development of the Society within the national and international photogrammetric context and his record of the deliberations which took place between 1947 and 1952 will be of particular interest to historians of our subject.This account was first published in a limited edition in 1971. Sufficient interest has since been expressed to prompt a wider circulation through publication in the Photogrammetric Record.The author served the Society continuously in several official capacities from 1953 to 1969 and he was elected to Honorary Membership in 1969.〈section xml:id="abs1-2"〉〈title type="main"〉RésuméLa Photogrammetric Society a été fondée en 1952. Excellente occasion pour faire le point qu'un vingtiéme anniversaire, a estimé le Conseil de la Société; pour rappeler les circonstances de sa naissance, les étapes de sa croissance et les décisions importantes prises depuis 1952. Ce qu'on invita Paul Lamboit à faire. Son exposé resitue la naissance et le développement de la Société dans le contexte national et international de la photogrammétrie; la relation qu'il fait des décisions prises entre 1947 et 1952 intéressera particulièrement ceux qui s'occupent d'histoire de la photogrammétrie.Ce rapport d'abord publié en édition limitée en 1971, a suscité un intérêt suffisant pour que l'on se presse en le publiant dans le Photogrammetric Record de le porter à la connaissance d'un plus large public.L'auteur a exercé différentes fonctions de 1953 à 1969 dans l'appareil de la Société. Il a étéélu membre honoraire en 1969.〈section xml:id="abs1-3"〉〈title type="main"〉Zusummenfussung1952 wurde die Britische Gesellschaft für Photogrammetrie gegründet. Der Rat der Gesellschaft erwog, dass der zwanzigste Jahrestag eine günstige Gelegenheit sei, um die Ereignisse, die zur Gründung der Gesellschaft führten sowie die bedeutenden Veranstaltungen, die stattfanden und die Entscheidungen, die getroffen wurden, darzustellen. Aus diesem Grunde wurde Paul Lamboit eingeladen, diesen historischen Rückblick zu schreiben. Er hat dabei die Gründung und die Entwicklung der Gesellschaft in den nationalen und internationalen photogrammetrischen Zusammenhang gestellt nd sein Bericht über die zwischen 1947 und 1972 erfolgten Beratungen wird für an unserer Sache interessierte Historiker sehr aufschlussreich sein.Diese Zusammenstellung wurde erstmals in einer begrenzten Auflage im Jahre 1971 veröffentlicht. Genügend Interesse wurde inzwischen bekundet, um eine weitergehende Verteilung mit Hilfe des Photogrammetric Record zu veranlassen.Der Autor diente der Gesellschaft kontinuierlich in verschiedenen Ämtern von 1953 bis 1969, wo er aum Ehrenmitglied gewählt wurde.

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: 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: Stimulated by promising overseas results with colour aerial photography and encouraged by its potential for solving local problems, the Forests Commission, Victoria, embarked on a series of trials with colour photography in 1965. Early results showed great promise and resulted in further work. This paper describes the methods and results of 70 mm and 35 mm trials concerned with the evaluation of various photographic films. An important aim of the study was to build up a working knowledge of the techniques of using aerial films other than conventional panchromatic black and white and to assess their value under Australian conditions.〈section xml:id="abs1-2"〉〈title type="main"〉Résumé Stimulés par les résultats obtenus outre-mer en matière de photo aérienne en couleur, et disposant d'un potentiel adéquat, le Forests Commission, Victoria a entrepris en 1965 une série d'essais, dès le départ très encourageants. On décrit ici les essais d'évaluation de différents types de film (70 mm et 35 mm); le but était de se familiariser avec la couleur et d'en étudier les conditions d'emploi sous les latitudes australiennes.〈section xml:id="abs1-3"〉〈title type="main"〉ZusammenfassungAngeregt durch erfolgversprechende Ergebnisse mit Farbluftbildern in Übersee und ermutigt durch die Möglichkeiten zur Lösung lokaler Probleme unternahm die Forstkommission in Viktoria (Australien) eine Reihe von Versuchen mit Farbaufnahmen im Jahre 1965. Diese Versuche erwiesen sich vielversprechend und wurden fortgesetzt. Im Artikel werden die Verfahren und Ergebnisse von Versuchen mit 70 mm und 35 mm Aufnahmen zur Bewertung verschiedener photographischer Materialien beschrieben. Ein wichtiges Ziel der Untersuchung war das Erlangen von Kenntnissen über die Verfahren zur Verwendung nichtkonventioneller panchromatischer Schwarz-Weiss-Filme und deren Bewertung unter australischen Bedingungen.

Notes: A short review is given of photogrammetric methods in use for the test recording of petroglyphs and archaeological sites. Two simple field methods employed by archaeologists to record petroglyphs are also described in order to highlight the complexity of photogrammetric techniques and to query their validity.〈section xml:id="abs1-2"〉〈title type="main"〉RésuméBrève revue de méthodes photogrammétriques en usage pour enregistrer pétroglyphes et sites archéologiques. On décrit en sus deux méthodes employees par les archéologues dont la simplicité contraste avec la complexité des méthodes photogrammétriques.〈section xml:id="abs1-3"〉〈title type="main"〉ZusammenfassungKurzer Bericht über die photogrammetrischen Verfahren zur versuchs-weisen Aufzeichnung von Petroglyphen und archäologischen Fundstätten. Zwei von Archäologen zur Aufzeichnung von Petroglyphen verwendete einfache Feldverfahren werden ebenfalls beschrieben, um die Komplexität der photogrammetrischen Methoden zu beleuchten und ihre Richtigkeit zu überprüfen.

Notes: The CP1 plotter has been employed to produce, from low altitude aerial photography, a detailed map at a scale of 1: 1000 of a major landslide which occurred in an urban area of Hong Kong with extreme relief differences. Geomorphological features of the landslide could be interpreted easily from the aerial photographs and shown on the map which provided an accurate record of the disaster. Experiments with computer mapping of the landslide using a limited number of height points obtained by the CP1 plotter have also been carried out and the results indicated that useful data could be obtained rapidly to meet urgent needs for the preliminary stage of investigation and the planning of reconstruction works after the disaster.〈section xml:id="abs1-2"〉〈title type="main"〉RésuméA partir d'une couverture aérienne à faible altitude, on a restitué au CP1 et à l'échelle du 1: 1000 une carte détaillée d'un important glissement de terrain survenu à Hong Kong et présentant d'extrêmes variations de relief. Les caractéristiques géomorphologiques du glissement aisément perçues sur les photos aériennes ont été reportées sur la carte. On a mené d'autre part des essais de cartographie numérique à partir de semis produits par le CP1, qui prouvent qu'on peut ainsi obtenir rapidement des données utiles aux enquêtes et mise sur pied des travaux de reconstruction.〈section xml:id="abs1-3"〉〈title type="main"〉ZusammenfassungDer CP1 Plotter wurde zur Herstellung einer detaillierten Karte im Massstab 1: 1000 nach Luftbildern aus geringer Flughöhe verwendet, um einen grösseren Erdrutsch mit extremen Höhenunterschieden im Stadtgebiet von Honkong zu kartieren. Die geomorphologischen Erscheinungen des Erdrutsches konnten leicht an Hand der Luftbilder interpretiert und auf der Karte dargestellt werden, die eine genaue Aufzeichnung der Katastrophe vermittelte. Es wurden auch Versuche mit einer rechnergesteuerten Kartierung des Erdrutsches mit Hilfe einer begrenzten Menge von Höhenpunkten, die mit dem CP1 Plotter gemessen wurden, durchgeführt. Die Ergebnisse besagten, dass dadurch wichtige Daten schnell ermittelt werden können, um dringende Anforderungen für eine vorläufige Einschätzung sowie die Planung des Wiederauf baus nach dem Unglück zu befriedigen.

Notes: A close range photogrammetric system, developed around a 35 mm Pentax camera fitted with a wide angle lens (f = 21 mm) and an early Zeiss wide angle multiplex, has proved useful for both instruction and research. Student exercises involve all phases of photogrammetry, from establishing ground control to plotting, and permit the integration of useful statistical routines for data analysis. Research applications have centred on the topographic mapping of microscale landforms at scales of 1: 1 to 1: 10 with accuracies of ± 1 mm to ± 5 mm.〈section xml:id="abs1-2"〉〈title type="main"〉RésuméUn système mis au point pour la photogrammétrie à courte distance, et dont les éléments essentiels sont une chambre Pentax (f = 21 mm) et un Zeiss grand angle multiplex, a fait la preuve de son utilité tant pour l'instruction que pour la recherche. Les exercices proposés aux étudiants comportent toutes les phases réelles, depuis l'établissement d'un canevas d'appui jusqu'à la restitution. Les applications à la recherche sont centrées sur la cartographie des microreliefs à des échelles variant de 1: 1 à 1: 10 avec des exactitudes variant de ± 1 mm à± 5 mm.〈section xml:id="abs1-3"〉〈title type="main"〉ZusammenfassungEin Aufnahme- und Auswertesystem zur Nahphotogrammetrie, bestehend aus einer 35 mm Pentax Kamera, die mit einem Weitwinkelobjektiv (f= 21 mm) ausgerüstet war, und ein alter Weitwinkel-Multiplex von Zeiss haben sich bei der Ausbildung und Forschung als nützlich erwiesen. Bei den studentischen Übungen werden alle Phasen der Auswertung von der Passpunktbestimmung im Gelände bis zur Stereokartierung erfasst, wobei es auch möglich ist, statistische Tests zur Datenanalyse einzubeziehen. Die Forschungsarbeiten konzentrierten sich auf die Herstellung topographischer Karten von kleinmassstäbigen Geländeformen in den Massstäben 1: 1 bis 1: 10 mit Genauigkeiten von ± 1 mm bis ± 5 mm.

Notes: Lidar and photogrammetry have both been evaluated for detecting shortterm coastal change using the Black Ven mudslide, Dorset as a case study. A lidar-generated digital elevation model (DEM) was obtained and initially compared with a DEM generated using available 1:7500 scale aerial photography and automated digital photogrammetry. The quality of these two data sets was assessed using a third DEM, derived using a total station and conventional ground survey methods. The vertical accuracies (rms error) of the lidar and photogrammetry were 0.26m and 0.43m respectively, although both data sets displayed a tendency to generate heights slightly lower than the elevation of the terrain surface. The quality of the two data sets was then assessed with respect to local slope angle. The accuracy of photogrammetrically derived elevations varied with slope and more so than in the case of lidarFrom these basic tests, lidar has proved to be more accurate than photogrammetry for soft-cliff. monitoring. Further research is required to establish whether this trend is applicable to other data sets and specifically for photogrammetric data acquired using larger scale imagery

Notes: A model of a multiple box girder bridge, constructed at a scale of 1: 12, was subjected to an ultimate load test. Deformations were measured photogrammetrically using the method of false parallax. Modifications to the method are described which were necessary to accommodate the three dimensional object and to allow for the fact that the camera stations were not constant from one load stage photograph to the next. An accuracy of ± 0·2 mm in the measured deformations was achieved.〈section xml:id="abs1-2"〉〈title type="main"〉RésuméUn modèle de boîte de vitesse à l'échelle 1: 12 est soumis à des essais de rupture; on mesure les déformations par photogrammétrie, en utilisant la méthode de la “pseudo-parallaxe”; des modifications ont dûêtre apportées à la méthode pour tenir compte du volume de l'objet et de la variation des points de vue entre les différents états de charge. On a obtenu une exactitude de ± 0·2 mm.〈section xml:id="abs1-3"〉〈title type="main"〉ZusammenfassungEin Modell einer Hohlkasten-Balkenbrücke im Masstab 1: 12 wurde einem maximalen Belastungstest unterworfen. Die Deformationen wurden dabei photogrammetrisch mit Hilfe von Pseudoparallaxen gemessen. Beschreibung der Veränderungen der Methode, die wagen der Anpassung an das dreidimensionale Objekt notwendig waren und der Tatsache Rechnung trugen, dass die Kammerstandpunkte bei den Belastungen nicht konstant blieben. Die Deformationen konnten mit einer Genauigkeit von ± 0·2 mm bestimmt werden.

Notes: This paper describes the modification, calibration and testing of a non-metric Linhof Technika View camera for use in the stereophotogrammetric mapping and analysis of dental features. The importance of correcting for errors of convergence in very short range stereophotogrammetry is stressed.〈section xml:id="abs1-2"〉〈title type="main"〉RésuméOn décrit les modification, étalonnage et test d'une chambre non métrique Linhof-Technika en vue de photogrammétrie dentaire; on insiste sur la nécessité qu'il y a de corriger l'erreur de convergence pour de telles études.〈section xml:id="abs1-3"〉〈title type="main"〉ZusammenfassungBeschreibung des Umbaus, der Kalibrierung und der Testung einer nichtmetrischen Linhof-Technika-Kamera für die stereophotogrammetrische Kartierung und Analyse von Zahnstrukturen. Betonung der Bedeutung der Korrektur von Konvergenzfehlern bei der Nahphotogrammetrie mit sehr geringen Aufnahmeentfernungen.

Notes: Research into both extraction of man-made objects and automatic change detection from aerial and satellite images has made significant progress in recent years. This paper presents an approach, based on a fuzzy logic system, for the identification of suburban roads in Ikonos images. The linguistic variables are the mean and standard deviation (SD) of different objects with Gaussian membership function. After the roads have been identified provisionally and their skeleton extracted, the skeleton can be vectorised and then used as direct input to a GIS for further analysis. The method was tested on an Ikonos “Geo” image covering Bilesavar in north-western Iran. For the suburban area of Bilesavar, the results showed that grey scale values ranged from 20 to 190 for non-roads and 226 to 228 for roads, the optimum width of the Gaussian kernel function was 3 and the SD was 0.4. It was also found that about 91% of main roads with a width of 6 to 12 pixels could be extracted from high resolution satellite imagery by the algorithm. The computer program for this study has been developed in visual C++ based on Windows 98

Notes: Books reviewed:S. Openshaw and R. J. Abrahart, GeocomputationM. Craglia and H. Onsrud, Geographic Information Research: Transatlantic PerspectivesP. J. Halls, Spatial Information and the EnvironmentJ. Sievers and T. Schneider, Second International Symposium on Geographical Names: Geonames 2000J. C. Leachtenauer and R. G. Driggers, Surveillance and Reconnaissance Imaging Systems: Modelling and Performance PredictionP. A. Longley, M. F. Goodchild, D. J. Maguire and D. W. Rhind, Geographic Information Systems and ScienceY. Q. Chen and Y. C. Lee, Geographical Data AcquisitionK. Borre, Plane Networks and their Applications.A. Hirschfield and K. Bowers, Mapping and Analysing Crime Data: Lessons from Research and PracticeO. Koelbl, Proceedings of the Oeepe Workshop on Automation in Digital Photogrammetric ProductionRICS Books, Vertical Aerial Photography and Derived Digital Imagery: Client Specification GuidelinesD. E. Reeve and J. R. Petch, Gis Organisations and People: A Socio-Technical Approach