Showing papers by "International Institute for Applied Systems Analysis published in 1979"

New options for team research via international computer networks

Abstract: In this paper, international team research (ITR) is discussed as an object for measurement, systems analysis, and management. The paper is intended as a contribution to the development of a “problem” orientation in scientometrics. In the authors' view, scientometric studies can help solve the problem of efficient ITR in several ways-for instance, by identifying needed improvements in (a) international scientific communication in general, (b) scientific interactions within and among research teams as part of the creative process, and (c) the overall international usage of existing scientific knowledge. The paper discusses the machinery of ITR, models of scientific communication, and some original experience in using computers and telecommunications as tools for scientific interaction. All of these are potential objects for scientometric investigation. The paper itself performs some first steps in obtaining economic parameters for the different forms of international team research.

Criteria for Proportional Representation

Abstract: We investigate methods to allocate seats in proportional representation systems in terms of several underlying common-sense properties. In particular, the idea of stability is introduced, and the method of Jefferson or d'Hondt is characterized.

Constructive Solutions to the Co2 Problem

Abstract: CO2 effects on climate receive increasing attention at the scientific, public, and political level. Most of the analyses, however, and of the talk, concentrate on the effects themselves, including the dire consequences for poor humanity. One can reflect, however, that if man has grown big enough to interfere with the great nature cycles, he may also be grown enough to take care of the problems. In this presentation three proposals are briefly examined and their cost very roughly assessed. The first one, originally proposed by W. Nordhaus, a fairly classical economist, uses an economical constraint, taxation, to scare the energy consumer out of fossil fuels into energy sources which do not release CO2: nuclear, solar or even biomass. Taxes are so adjusted that a predetermined CO2 level in the atmosphere will never be reached. The intermediate path is however left free for an eventual optimization, i.e. minimization of economic costs. In the second, originally proposed by Dyson, 1012 sycamore trees should be planted, hoping they will in time mop up CO2 from the atmosphere and store it in form of standing crop and humus. Apart from a certain number of problems arising from such a large scale plantation-after all active humanity is made of only ∼109 people-the system appears up to a point selfdefeating because the decrease in albedo which comes with the trees will move temperature up, at least at the beginning, and only after many years the CO2 sequestered will compensate for that. In the third, originally proposed by the author, a fuel cycle is suggested in analogy to the fuel cycle of nuclear reactors. CO2 is then separated from stack gases, together with SO2 and other noxious components, and then stored in proper geological structures, e.g. exhausted oil and gas fields, or in the deep ocean making use of thermohaline currents to diffuse it in depth. The same result can be obtained by separating air and burning fuels with oxygen. The costs for CO2 control are relatively high in all three cases, but are certainly inside the capacity of the energy system to digest them.

Water: A Perspective on Global Issues and Politics

Abstract: The uneven distribution of water in the world is reviewed. Development of water quality problems is traced. The policy options for sectoral uses, especially in terms of rural and urban water supply, agriculture, industry, and hydroelectric power are outlined. The present status of water development in these four sectors is provided on a regional basis for the whole world, and in certain cases national information is also given. Lack of water development in developing countries is emphasized, and possible investment costs are indicated. Social and environmental impacts of water development projects are discussed in detail under three categories of sub-systems: physical, biological and human. It is concluded that the major problem is not one of the Malthusian specter of impending scarcity but one of instituting more rational management practices. Time has come to shift emphasis to comprehensive land and water planning, treating land and water as an integrated and interacting unit.

A utility function for time streams having interperiod dependencies

Abstract: A utility function that is separable over time cannot accurately reflect the preferences of a decision maker whose attitude toward risk in a given period of a time stream depends on the particular outcome in the previous and/or following period. In this paper we use conditional utility independence to give assumptions that do allow such preferences to be quantified. For a T-period time stream the result requires the assessment of T - 1 two-period utility functions and one scaling constant. If stationarity assumptions are appropriate, only one two-period utility function and two constants are required. MANY FACTORS serve to complicate the evaluation of alternative strategies that have impacts over time. Principal among them are the necessity of making tradeoffs between consequences in different periods and the uncertainty of the outcomes as to their magnitude and timing. These issues may be resolved with a von Neumann-Morgenstern utility function [10]. Such a utility function serves as a preference (or value) function in that it provides an ordering over certain outcomes and, in addition, its expectation provides a preference function over uncertain outcomes. The difficulties associated with this approach arise when the number of time periods is large, for the dimensionality of the utility function is equal to the number of time periods. The assessment of a one-dimensional (or one-attribute) utility function is relatively easy and that of a two-dimensional utility function still practical. However, without major simplifying assumptions, the assessment of high-dimensional utility functions is impractical. The problem is to find reasonable assumptions that reduce the assessment of the utility function to a manageable level without losing the flexibility to reflect the decision maker's true preferences accurately, and without losing the property of the utility function as a useful evaluator of uncertain outcomes.

Quotatone Apportionment Methods

Abstract: The problem of apportionment is that of allocating an integer number of seats “proportionally” among a set of states or regions as a fraction of their populations. An apportionment method satisfies quota if it accords to each state the exactly proportional rational number of seats due it rounded up or rounded down. A method is house monotone if no state's allocation goes down when the total number of seats to be distributed goes up. This paper gives a simple characterization of all house monotone methods satisfying quota. Further, a manner of exposition is formulated which unites several key house monotone apportionment methods, thus showing clearly their connections.

Dynamic linear programming models for livestock farms

Abstract: This paper considers the dynamic linear programming model for multispecies live-stock farming with a feed production subsystem. The problem is to determine the optimal livestock mix with the projected growth rate and corresponding development of feed production in order to obtain the maximum profit for the given planning horizon. As examples, the planning model for a dairy farm and the control problem of age-size structure of a biological population are given.

Understanding world models

Abstract: Computer models of the world system produce very different results, ranging from economic collapse and massive starvation in the 21st century to universal prosperity for double or triple the present world population. The strikingly different conclusions that arise make it urgent to compare them effectively with one another, and see what it is about them that produces such diverse policies. And even insofar as the policies are similar, one would like to know more about how they arise from the models. This paper suggests a line of analysis that permits comparison of properties among such models. It takes up two ways of seeing what is in a model in addition to examining its documentation: first, making alternative transparent models that check the partial results of the complex model; and, second, 'black-box' experiments leading to a truncated linear form of the complex model. These two methods of assessment are designed to replace most of the documentation, and to allow the user to understand more effectively what assumptions he commits himself to in using the model.

On the scenario approach to simulation modeling for complex policy assessment and design

Abstract: This paper reviews the major issues posed by scenario-based simulation modeling in the policy process, using agricultural policy as an example of a complex decision arena. Policy is seen as a process by which decision makers use the instruments under their control to approach the general goals of society. Models can help to choose instrument settings, evaluate policy options, and assess their appropriateness to a particular situation. But they cannot design policy; the interactions between policy makers and models are critical if modeling is to be useful in the policy process. Policy models must be oriented to the factors that focus and constrain judgments in the real world, as well as toward the substantive problems motivating analyses. These include the actors within the system, as well as the geographic and disciplinary contexts of the problems. Scenario-writing provides a way of ordering understanding and judgment about different phenomena to help users interact most effectively with a model and to insure that the perspectives of the model are most appropriate to the needs of the decisionmaker. It is an iterative and evolutionary process which can provide a great deal of insight into the assessment phase of policy design.

Storage systems dependent on multivariate stochastic processes

Abstract: A model of stochastic storage for dams is presented. Inflows are governed by a multivariate distribution. A computational procedure for determining optimal reservoir operation is given.

The global energy system.

Abstract: A global energy system is conceptualized and analyzed, the energy distributor sub-system of the worldwide supranational system. Its many interconnections are examined and traced back to their source to determine the major elements of this global energy system. Long-term trends are emphasized. The analysis begins with a discussion of the local systems that resulted from the deployment of technology in the mid-nineteenth century, continues with a description of the global system based on oil that has existed for the past two decades, and ends with a scenario implying that an energy transition will occur in the future in which use of coal, nuclear, and solar energy will predominate. A major problem for the future will be the management of this energy transition. The optimal use of global resources and the efficient management of this transition will require a stable and persistent global order.

Optimisation non Differentiable: Methodes de Faisceaux

Abstract: We define a class of descent methods to minimize a nondifferentiable function. These methods are based on a representation of the objective which combines a quadratic approximation and the usual approximation by a piecewise linear function. Hence, they realize a synthesis between quasi-Newton methods and cutting plane methods. In addition, they have the particularity of requiring no sophisticated line search. They are also presented in ref. [7] (in English).

Introduction to IIASA: Applying systems analysis in an international setting†

Abstract: IIASA is not only an institution, it is an idea -- the idea that despite differences in economic, political, and social systems, scientists from East and West can work together to help resolve the problems that face all mankind. In the six years of its existence, the Institute has demonstrated that this once "unrealistic" idea can become a reality. In the years ahead, it must strive, in collaboration with the scientific communities, governments, and industry throughout the world, to bring that idea to its fullest realization.

Attitudes, Accounts and Operational Realities: Thoughts and Illustrations on the Inter-Disciplinary Development of O.R.

Abstract: It is suggested that operational researchers could improve the practice of their discipline by developing greater understanding and appreciation of some of the conventions of the accounting profession, and their rationale. The general point is illustrated by reference to case examples.

Exploitable Surplus in N-Person Games

Abstract: Any cooperative n-person game with transferable utility has a noncooperative mode in which the players sell out of their positions to an external market of entrepreneurial organizing agents. Assuming a market of price takers, this game of competitive self-valuation always has an equilibrium price solution. Every core imputation in the original game constitutes a set of equilibrium prices. If there is no core the entrepreneurs can exploit the coalitions for a profit, i.e., they realize a positive rent for their organizing function. Application is made to determining fair wages to labor, and finding equilibrium prices for legislators selling their votes.

Modeling the Impact of Large-Scale Energy Conversion Systems on Global Climate

Abstract: There are three energy options which could satisfy a projected energy requirement of about 30 TW and these are the solar, nuclear and (to a lesser extent) coal options. Climate models can be used to assess the impacts of large scale deployment of these options. The impact of waste heat has been assessed using energy balance models and general circulation models (GCMs). Results suggest that the impacts are significant when the heat input is very high and studies of more realistic scenarios are required. Energy balance models, radiative-convective models and a GCM have been used to study the impact of doubling the atmospheric CO2 concentration. State-of-the-art models estimate a surface temperature increase of 1.5-3.0°C with large amplification near the poles, but much uncertainty remains. Very few model studies have been made of the impact of particles on global climate, more information on the characteristics of particle input are required. The impact of large-scale deployment of solar energy conversion systems has received little attention but model studies suggest that large scale changes in surface characteristics associated with such systems (surface heat balance, roughness and hydrological characteristics and ocean surface temperatures) could have significant global climatic effects.

Langfristige Strategien zur Energieversorgung

Abstract: Long-term energy supply strategies. The present-day energy debate has concentrated on the short to medium term aspects of the pressing energy problem. From the viewpoint of a national economy, the energy crisis definitely dictates such a strategy. Structural changes, i. e. research and development of advanced technologies for the energy supply sector as well as improvements of end-use devices, however, are inherently of a long-term nature. At the same time, it is of utmost importance to channel measures becoming effective in the long run into the correct direction from the very beginning. The concept of developing long-term energy supply strategies therefore serves as a means for comprehensive orientation in the energy question. It is not so much the predictions but rather the guidelines that are of most importance. This paper describes long-term energy supply strategies for seven world regions, covering the whole globe. The question of compatibility and consistency for anticipated energy strategies of each of the seven regions is then brought into perspective.

On ε-Subgradient Methods of Non-Differentiable Optimization

Abstract: The theory of nondifferentiable optimization studies extremum problems of complex structure involving interactions of many subproblems, stochastic factors, multi-stage decisions and other difficulties.

IMPACTS of small-scale computing technology

Abstract: This paper was initiated through discussions at a seminar on "Managerial and Organizational Consequences of Mini/Micro Computers" sponsored by the Management and Technology Area of the International Institute for Applied Systems Analysis (IIASA) in Laxenburg, Austria on September 26-28, 1978.