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- Type:
- Document
- Fecha de Creacion:
- 1987
- Collection:
- System Dynamic Society Records
- Collecting Area:
- University Archives
- Collection ID:
- ua435
- Parent Record(s):
- 23d738ba88f8333bc39725f9cb5bd0b8, 83d7d84d4a906b77a877f50ccddf0ccd, and ef456d2a6c943c510d5169405dfd9416
- Descripción:
- The growing amount of the foreign debt of the developing countries shapes a gloomy future for most of them. The chances for maintained growth fueled by internal saving is nil if the service of the debt is satisfied, as it has to be to avoid international isolation. This is particularly true in the case of Argentina, with a debt equivalent to two thirds of its GDP, and its debt service representing more than 5 per cent of the GDP. After showing the historical facts about the Argentine economy, this paper presents a very simple version of a growth model type Harrod-Domar, adapted to the parameters of the local economy. Then the model is used for answering to “what-if” type of questions, wich arise from different plausible scenarios. Finally, it is analyzed the probabilistic generation of scenarios and related technical problems using DYNAMO.
-
- Type:
- Document
- Fecha de Creacion:
- 1987
- Collection:
- System Dynamic Society Records
- Collecting Area:
- University Archives
- Collection ID:
- ua435
- Parent Record(s):
- 23d738ba88f8333bc39725f9cb5bd0b8, 83d7d84d4a906b77a877f50ccddf0ccd, and ef456d2a6c943c510d5169405dfd9416
- Descripción:
- In previous work, the analysis of the effects of aggregating simple dynamic systems has been studied by applying methods developed for thermodynamic systems in order to take account of stochastic effects. This approach is based on the Master Equation for the probability density of the contents of a vector of system levels. The goal of these studies is to determine the dynamic characteristics of systems composed of a population of sub-systems with the same dynamic structure while accounting for novel behavior that is introduced by the process of aggregating the sub-systems into the larger system.In this paper, the Master Equation analysis is applied to four versions of a Commodity Cycle model to determine the nature of modes of behavior that arise from the process of aggregating a population of entities whose dynamic structure is derived from the oscillatory structure of the commodity cycle model. The approach used here is novel in two respects. It contracts with the more recently developed analysis of chaotic systems in which non-linear, aggregate or lumped-parameter models generate behavior that is unpredictable while not being stochastic. In those models, no attempt is made to explain the large-scale or aggregate chaotic behavior in terms of the sub-systems. Compared to previous work in the same vein, this paper addresses itself to a slightly larger model as part of a natural progression in the analysis of ever-more complex systems by Master Equation methods.
-
- Type:
- Document
- Fecha de Creacion:
- 1987
- Collection:
- System Dynamic Society Records
- Collecting Area:
- University Archives
- Collection ID:
- ua435
- Parent Record(s):
- 23d738ba88f8333bc39725f9cb5bd0b8, 83d7d84d4a906b77a877f50ccddf0ccd, and ef456d2a6c943c510d5169405dfd9416
- Descripción:
- The study on urban ecology has its world-wide significance due to the phenomenon of growing “urbanization” nowadays. With System Dynamics, the author has studied the simulation model of ecosystem in Beijing. While determining the variable set and doing the sensitivity analysis , the author has posed a new method. A retrospective verification is done with historical data and then several strategies are analyzed by using this model. The research shows that the simulation model is an important method in urban ecosystem study and of great value to practical use.
-
- Type:
- Document
- Fecha de Creacion:
- 1987
- Collection:
- System Dynamic Society Records
- Collecting Area:
- University Archives
- Collection ID:
- ua435
- Parent Record(s):
- 23d738ba88f8333bc39725f9cb5bd0b8, 83d7d84d4a906b77a877f50ccddf0ccd, and ef456d2a6c943c510d5169405dfd9416
- Descripción:
- This paper presents a system dynamics model of the transportation energy demand in Singapore. The transportation sector in Singapore is heavily dependent on oil and is one of the major consumers of energy. Thus, it is essential to model the transportation energy demand to be able to see the implications of changes in economic situation and oil prices.The transportation sector is divided into passenger transport and freight transport. Five modes of passenger transport are considered. The Mass Rapid Transit is included in this model as it will be the major mode of public transport in 1990's. The ratio of per capita energy consumption to per capita income is used to indicate the change in energy consumption as income changes. With this as a basis policy changes such as price of fuel and regulation of ownership of private motor vehicles are made.The model can be used to test various scenarios, e.g., changes in economic conditions and in fuel prices. The simulation results can then be used to examine the various policies that could be implemented to alter the transportation energy demand situation. The model has been calibrated using available information and some policy analyses have been performed with the model.
-
- Type:
- Document
- Fecha de Creacion:
- 1987
- Collection:
- System Dynamic Society Records
- Collecting Area:
- University Archives
- Collection ID:
- ua435
- Parent Record(s):
- 23d738ba88f8333bc39725f9cb5bd0b8, 83d7d84d4a906b77a877f50ccddf0ccd, and ef456d2a6c943c510d5169405dfd9416
- Descripción:
- Innovations in automated intelligent knowledge based systems (IKBS) including expert systems (ES) could have a major impact on the development of system dynamics methodology. This paper reports on the characteristics of an integrated system for modelling and managing complex, dynamic systems currently being developed. Essentially, the system consists of five sectors namely a simulation model; a set of quantitative measures as macros; means; a real world data set; an adaptive knowledge based system including an expert system; a policy decision making system. It is suggested that such an integrated approach to system dynamics could further enhance the usefulness of the methodology to modelling and managing complex systems.
-
- Type:
- Document
- Fecha de Creacion:
- 1987
- Collection:
- System Dynamic Society Records
- Collecting Area:
- University Archives
- Collection ID:
- ua435
- Parent Record(s):
- 23d738ba88f8333bc39725f9cb5bd0b8, 83d7d84d4a906b77a877f50ccddf0ccd, and ef456d2a6c943c510d5169405dfd9416
- Descripción:
- Successful innovation management depends upon both, the intrinsic attributes of the new product to be marketed and the firm's internal performance like cost management, timely delivery and quality assurance. The impact of these latter aspects is frequently neglected in the design of models for supporting decision making in innovative firms.A model is outlined to study the market response of different manufacturing policies for innovative goods. It allows e.g. the evaluation of an aggressive strategy with large production capacities from the outset, or a more tentative behavior to avoid the pressures stemming from high fixed cost and the risks of eventually idle capacity.
-
- Type:
- Document
- Fecha de Creacion:
- 1987
- Collection:
- System Dynamic Society Records
- Collecting Area:
- University Archives
- Collection ID:
- ua435
- Parent Record(s):
- 23d738ba88f8333bc39725f9cb5bd0b8, 83d7d84d4a906b77a877f50ccddf0ccd, and ef456d2a6c943c510d5169405dfd9416
- Descripción:
- Using data from a large primary steel products company, two Industrial Dynamics simulation models were constructed to study the effects of process control computer-generated information on management control systems. The first model represented the existing system, the other proposed process control/business control interfaced system.The research provides an initial step in the solution of the problem of integrating process control and management control systems by investigating the relationship between process information and control decisions at the operating level of management.The proposed system model indicated much less fluctuation in inventory levels following changes in demand, lower backlog ratios, higher inventory ratios, lower delivery delay ratios, and higher levels of consumer satisfaction. The proposed system was also fairly insensitive to changes in the time between transmissions from the process control systems to the management control systems once the interface was effected.
-
- Type:
- Document
- Fecha de Creacion:
- 1987
- Collection:
- System Dynamic Society Records
- Collecting Area:
- University Archives
- Collection ID:
- ua435
- Parent Record(s):
- 23d738ba88f8333bc39725f9cb5bd0b8, 83d7d84d4a906b77a877f50ccddf0ccd, and ef456d2a6c943c510d5169405dfd9416
- Descripción:
- The formal KSIM (Kane's SIMulation) model is equivalent to a particular system dynamics (SD) model. On the basis of this equivalency, we use the KSIM and cross-impact concepts to simplify the SD modeling steps, and a new procedure --CISD from the abbreviation for Cross Impact System Dynamics which is technically simpler and more normative, has been introduced. CISD is well applied in the field of Technology Assessment (TA). An example for TA of agricultural chemicals with CISD is presented. A general computer program for CISD which is called CISD-FORTRAN makes CISD procedure more widely used with facilities even for nonspecialists.
-
- Type:
- Document
- Fecha de Creacion:
- 1987
- Collection:
- System Dynamic Society Records
- Collecting Area:
- University Archives
- Collection ID:
- ua435
- Parent Record(s):
- 23d738ba88f8333bc39725f9cb5bd0b8, 83d7d84d4a906b77a877f50ccddf0ccd, and ef456d2a6c943c510d5169405dfd9416
- Descripción:
- The paper presents a preliminary attempt for application of system dynamics in the study of urban water using and its management.The SD model of urban water using describes the complicated system behavior. It will help us to understand and trace time interval behavior of urban water using system, to observe and handle dynamic trend of system behavior, to obtain the features of urban water using in different time. Therfrom we may have a quantified rational knowledge about water demand and have to find an effective may to strengthen scientific management of urban water using, to promote rationalization of urban water using, to save water resources and to resolve unbalance between supply and demand. Meanwhile, necessary informations and quantized references should be provided for administration and departments concerned to determine the speed of economic development, study layout and structure of industrial development, adjust key points and methods for urban water using.
-
- Type:
- Document
- Fecha de Creacion:
- 1987
- Collection:
- System Dynamic Society Records
- Collecting Area:
- University Archives
- Collection ID:
- ua435
- Parent Record(s):
- 23d738ba88f8333bc39725f9cb5bd0b8, 83d7d84d4a906b77a877f50ccddf0ccd, and ef456d2a6c943c510d5169405dfd9416
- Descripción:
- As an effective method of understanding the dynamic behavior of complex systems, system dynamics has great potential in the study of the dynamic course of drug absorption, distribution, metabolism, excretion and effect, which is the content of the disciplines called pharmacokinetics and pharmacodynamics. Two ways of applying SD are discussed: using DYNAMO to solve the traditional pharmacokinetic models --- compartment models and combining knowledge of pharmacokinetics and pharmacodynamics to set up advanced models under the paradigm of system dynamics. The application of the method, technique and modeling view of system dynamics to pharmacokinetics and pharmacodynamics can be very helpful and fruitful.