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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 authors present models, written in Dynamo language, used for reconstituting the demographic evolution of China between 1953 and 1978, and for dynamic simulations of the Chinese population. These models incorporate standard features of demographic projections but also a highly disaggregated sub-system of the female fertility, by age of women and number of children ever born. The spontaneous evolution of population is easily analyzed; any number of changes in fertility and/or mortality can be simulated, together with their consequences on population figures.The paper presents simulations of modifications in the trends of mortality and fertility. The effects of such modifications are discussed.The authors show the importance of existing stocks of people (by sex, age and number of children) for understanding and predicting the evolution, “natural” or consecutive to governmental actions, in population parameters; the evolution can be accelerated or delayed due to structural constraints.The short- and long-term effects of the possible evolutions in demographic parameters on the several stocks (population structures) are discussed, in the perspective of their usefulness for decision-makers. The disaggregation of the model allows to make sectorial projections for each simulated hypothesis.The feasability of a stabilized population in China by the year 2000 is also discussed.
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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:
- In this study, a prototype expert system to support system dynamics modelling is designed by organizing the knowledge structures of generic patternized expectations and the rules on how to construct system dynamics models. The system is a production-rule-oriented consultation system written in PROLOG. The proposed system covers the system conceptualization in part, system modelling, and generation of simulation program. Brief executing processes of the proposed system are: 1) Extracting concepts (nodes) within a system by perceiving action/decision making and by inferring the causal relations (links). 2) Preparing a causal-loop diagram of the system automatically by interconnecting the causal relations and by eliminating inappropriate links. 3) Transforming the causal-loop diagram into a flow-diagram automatically, and generating a simulation program. The proposed system has a knowledge base of facts acquired in the systems modelling, to facilitate the modelling of a system related to the ones dealt with in the past. Some application examples are provided to verify the applicability of the proposed system.
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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:
- This paper puts forward the idea that essential parts can be removed from a SD model without harm if the model is revised successively during the simulation. The revision requires an optimization package, called DYSMOD (Dynamic Simulation Model Optimizer and Developer). A multi-stage production model, developed by J. M. Lyneis, is used for demonstrating that the idea works in practice.
-
- 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:
- Accounting Dynamics (AD) is a methodology for the modelling and simulation od accounting using System Dynamics. Accounting identifies and measures economic transactions of an entity, and communicates these data to both internal and external decision makers. Thus it may be said that accounting controls resource allocations in social systems. In this context a simulation model described in terms of accounting will be very effective in order to analyze and project the behavior of social systems. In our model we emphasize the structure-dependent nature of System Dynamics. The AD model depicts the structure of accounts in an economic entity. The structure of accounts reflects charge-and-discharge relationships of accountabilities. Therefore the AD model seems to have a close relationship to the real world. The definition of accounting by R. Mattesich, i.e., the method of quantitative description and projection of income circulation and of wealth aggregates in macro and micro economy (Mattessich 1964), will be best met by AD. And accounting principles will be tested for their validation by the AD model simulation. The AD model will be able to be built at various levels, e.g., industrial, urban, national, in social systems. In our first approach, we have focused on the industrial level, and we have made a prototype of AD corporate model in a business entity. We will suggest critical issues in the application of the AD model for higher levels of social 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:
- The well established theory and methodology of the assurance sciences, especially the probabilistic reliability and availability theory, is applied to the modeling of the dynamics of innovation adoption processes. In particular, this approach allows one to model the dynamics of the diffusion of innovations through complex organizational decision networks. The approach taken here is an analytic one. However, it provides a logical framework for dynamic computer aided approaches. As the management and control of the dynamics of the innovation adoption are becoming increasingly important, obvious extensions of this approach are in the direction of optimal control systems concepts and applications. A number of empirical examples from the American automobile and steel industries are discussed.
-
- 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 analyses the system of Tianjin Can Industry using System Dynamics method. It puts forward suggestions to the development decision and planning of the seventh five year and the year 2000 of the Can Industry. The model simulates and analyses emphatically the returns on various investment and the efficiency of various developing products, which should be a reference for the decision-maker.A new idea of using Optimal Technology to optimize the System when the model simulation is carrying on is brought forth in the paper, and good results are obtained.
-
- 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 purpose of this paper is to explore the thought criteria of modelling in system Dynamics.Thought criteria of system dynamics has appeared as a dynamic theory in the field of economics. This field has three characteristics: nonlinear fluctuation, time delay and qualitative transformation. These characteristics constitute the basis of model building in system dynamics.The concept of thought criteria is based on the process of cognition: Study of subject-- Modelling—Understanding of object. It is closely associated in series with interactive elements of the system. The modelling has been inspected in practice as a transitional link between subject and object so that modelling has turned into a cognitive and analytical method and will be used, first, to carry out simulated tests of the prototype and thus deepen our comprehension of it; secondly, to compare the specific properties of theoretical and experimental systems with those of the real system, and by means of the result from these comparisons, to improve a causal relation loop; and thirdly, to show a tendency to pass from qualitative analysis to quantitative analysis, thus leading to the combined assessment of the system. The rules of the combined of the application of the system model are identification, interchangeability, controllability, and availability.
-
- 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 consumption of resources and the environmental pollution caused by the discharge of waste materials and waste heat occur as useful products are being turned out in the social-economic activist activities. Based on the concept of entropy, the paper deals with the impact of tech-progress on every link of this process. This is the major mechanism for the impact of tech-progress on economics.
-
- 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 this study, we have selected chiba prefecture as an subject. Chiba Prefecture is located in the Metropolitan region which is made up of Tokyo Metropolis and three prefectures. Though its local power is not so high compared with others, Chiba Prefecture has been remarkably vitalized in recent years. In order to study how the life environment of our local society will change in the near future, we have designed a local development model based on the System-Dynamics and analyzed it until 2000. The whole model is made up of 6 sectors; population, industry, land and dwelling, finance, education and medical facility. In the population sector, we have studied the change in the age structure. In the industry sector, we have analyzed the change in the structure by studying agriculture as the representative of the secondary industry and tourist industry and retail as the representative of the tertiary industry. Based on such kind of analysis, we have concluded the followings in 2000. the population of Chiba Prefecture will reach the level of 6.27 millions. The secondary industry will grow move rapidly than the tertiary industry, it's will become post Industry Society. The local society might become advanced-age society, we way say that our Chiba Prefecture will be relatively comfortable to live, compared to the other areas of the Metropolitan Region.
-
- 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 development and utilization of global/world models in the context of political implications of world economic trends is overviewed in terms of three streams of research, that of multidisciplinary social scientists, of the econometricians, and of the system engineers. Socio-political processes impinge on world economic trends, just as trends in turn impact on politics, both national and international. The use of simulations rich in system dynamics for the study of international affairs is found to have much potential, as documented in findings obtained by researchers throughout the world.