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-
- Type:
- Document
- Date Created:
- 1987
- Collection:
- System Dynamic Society Records
- Collecting Area:
- University Archives
- Collection ID:
- ua435
- Parent Record(s):
- 23d738ba88f8333bc39725f9cb5bd0b8, 83d7d84d4a906b77a877f50ccddf0ccd, and ef456d2a6c943c510d5169405dfd9416
- Description:
- R-SD is a dynamic system model used to study the comprehensive development and utilization of water resources of rivers. This problem covers a wide range of aspects, such as hydraulic power generation, water transportation, flood cotrol, water consumption of industry and households, irrigation in agriculture, reservoir fishery, around-reservoir tourism and recreation facilities. R-SD also relates to the thermal power generation and land transportation. It is a system with multivariables, nonlinear and complex feedback structure. Usually, it is called as economic system of river-valley.This paper emphasises on the structure of R-SD model. First, it gives the interrelationship figures between the subsystems, then the main cause-and-effect chains and flowchart of the system. Finally, a part of the results of a case study is given. It turns out that during the comprehensive development and utilization of water resources of rivers, the emphasises should be placed on the development of hydraulic power generaion in association with water transportation and other aspects. Meanwhile, thermal power generation and land transportation should be jointly developed to promote the economic prosperity in the river-valley. In R-SD, we have also posed three degrees of satisfaction, which are guided to decide the development velocities and investment proportions of power generation, transportation, and water supply.
-
- Type:
- Document
- Date Created:
- 1987
- Collection:
- System Dynamic Society Records
- Collecting Area:
- University Archives
- Collection ID:
- ua435
- Parent Record(s):
- 23d738ba88f8333bc39725f9cb5bd0b8, 83d7d84d4a906b77a877f50ccddf0ccd, and ef456d2a6c943c510d5169405dfd9416
- Description:
- This is a paper about possibilities. It is the beginning of an investigation into the influence of perceptions of money on the dynamics of major economic policies. No concrete results are reported.We begin with anecdotal evidence that many economic policies are based on a local and static perception of money. Local in that it only considers the part of the economic environment which directly impacts on, or is impacted by, the policies being made. Static in that it considers this environment to be essentially unaffected by those policies.This usual perception of money is illustrated by exploring a number of common thoughts about money. This exploration reveals the confusion surrounding this perception. In order to penetrate this confusion, a step-by-step examination is conducted of the role that money plays in an economy. This examination leads to another perception of money: Money has no value itself; it is merely a proxy for economic product that already exists. This perception is more global and dynamic than the usual point of view. Global because the focus on economic product forces one to consider the full economic context of a transaction. Dynamic because that emphasis leads one to consider the impact of decisions on the whole economy.A number of everyday economic transactions are illuminated by the new perception of money in such a way that consideration of those transactions naturally relates them to a wider economic system. Armed with this appreciation of economic transactions, the anecdotes presented early in the paper are revisited. In this visit, the new perception of money automatically suggests different approaches that the decision maker could take.
-
- Type:
- Document
- Date Created:
- 1987
- Collection:
- System Dynamic Society Records
- Collecting Area:
- University Archives
- Collection ID:
- ua435
- Parent Record(s):
- 23d738ba88f8333bc39725f9cb5bd0b8, 83d7d84d4a906b77a877f50ccddf0ccd, and ef456d2a6c943c510d5169405dfd9416
- Description:
- Dental diseases dealt with in this study are cavities (fillings, extractions and crowns), pyorrhea and baby teeth.The total number of teeth with dental diseases in Japan changes year by year depending on oral conditions ans are affected by the number of dentists, economic conditions and technical progress.This model contains 4 sectors: demography, cavities, pyorrhea, and baby teeth. The demographic sector covers populations of 5 three-year age groups under 14 years of age and 13 five-year age groups above 15 years of age. The cavities sector and pyorrhea sector are composed of populations of five-year age groups, on the other hand, the baby teeth sector uses populations of three-year age groups.From the total number of defective teeth, dental busyness and total dental care costs in Japan are calculated yearly from 1963 to 2010. The simulation results are used to modify the dental policies of Japanese administrators.This study is a research project of the Japan Dental Association.
-
- Type:
- Document
- Date Created:
- 1987
- Collection:
- System Dynamic Society Records
- Collecting Area:
- University Archives
- Collection ID:
- ua435
- Parent Record(s):
- 23d738ba88f8333bc39725f9cb5bd0b8, 83d7d84d4a906b77a877f50ccddf0ccd, and ef456d2a6c943c510d5169405dfd9416
- Description:
- This paper describes the work of an M.I.T. research project (the Systems Thinking and the New Management Style Project) to bring systems thinking to top management groups in several large, successful corporations. The principal research tool, the “strategic forum” is described and critiqued. The paper then presents a case study to illustrate the strategic forum. Concluding remarks and supporting figures are presented at the end.
-
- Type:
- Document
- Date Created:
- 1987
- Collection:
- System Dynamic Society Records
- Collecting Area:
- University Archives
- Collection ID:
- ua435
- Parent Record(s):
- 23d738ba88f8333bc39725f9cb5bd0b8, 83d7d84d4a906b77a877f50ccddf0ccd, and ef456d2a6c943c510d5169405dfd9416
- Description:
- Earlier work demonstrated the presence of two long waves of colonial administration of different lengths (1490-1825 and 1826-1969). Whether these were separate episodes or examples of deeper underlying cyclical dynamics has implications for the existence of a common system dynamic over the long wave. To further inquire into the existence of a common cyclical rhythm these larger waves were decomposed through the use of a non-parametric stochastic measurement model.To do this a 490 year time series of colonial administrations is divided into ten episodes. A conditional Normal-Poisson model is proposed based on the assumptions of a stochastic process. The mean number of colonial administrations established and terminated over each episode are estimated, controlling for a quadratic time trend which would be induced if the system was not constant throughout an episode as assumed. Two sub-cycles are observed withing each of the two long waves of colonial administrations previously reported (Bergesen and Schoenberg, 1980).The presence of these matching sub-cycles provides a strong evidence supporting a common system dynamic in not only economic but political aspects in international life.
-
- Type:
- Document
- Date Created:
- 1987
- Collection:
- System Dynamic Society Records
- Collecting Area:
- University Archives
- Collection ID:
- ua435
- Parent Record(s):
- 23d738ba88f8333bc39725f9cb5bd0b8, 83d7d84d4a906b77a877f50ccddf0ccd, and ef456d2a6c943c510d5169405dfd9416
- Description:
- This paper outlines the characteristics of a search process for a planning paradigm to supplant the rational approach. After a brief discussion of the ongoing debate about the shortcomings of the prevailing paradigm, the central issues and assumptions in planning method are identified. These are then used to develop a set of criteria for procedural development and evaluation to guide the search for new approaches to planning. In the first part of the paper such criteria are operationalized to develop a series of procedures and models for community development planning and measures for evaluating these are given. The second part of the paper reports on the actual implementation and evaluation of the approach as an appropriate search strategy. The context, the models, and the evaluation results obtained in two applications, Door County Wisconsin and Janesville Wisconsin, are presented. Based on these applications the potential of the overall approach as a search strategy is discussed.
-
- Type:
- Document
- Date Created:
- 1987
- Collection:
- System Dynamic Society Records
- Collecting Area:
- University Archives
- Collection ID:
- ua435
- Parent Record(s):
- 23d738ba88f8333bc39725f9cb5bd0b8, 83d7d84d4a906b77a877f50ccddf0ccd, and ef456d2a6c943c510d5169405dfd9416
- Description:
- During the last year, the Technical Education Research Centers (TERC) has been combining microcomputer-based data gathering instruments with model-building software using the system dynamics approach to develop curriculum materials and software for high school students. The microcomputer laboratory aids students in collecting real-time data in such areas as heat, light, sound, motion, and water movement. Model-building helps students develop and test theories to study the data. An integrated software environment is being developed that will allow the data collected to be input directly into the models. In addition, the software will include an icon driven modeling language, algebraic function grapher, and spreadsheet to provide students with several different approaches to expressing model-building and simulation.
-
- Type:
- Document
- Date Created:
- 1987
- Collection:
- System Dynamic Society Records
- Collecting Area:
- University Archives
- Collection ID:
- ua435
- Parent Record(s):
- 23d738ba88f8333bc39725f9cb5bd0b8, 83d7d84d4a906b77a877f50ccddf0ccd, and ef456d2a6c943c510d5169405dfd9416
- Description:
- 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
- Date Created:
- 1987
- Collection:
- System Dynamic Society Records
- Collecting Area:
- University Archives
- Collection ID:
- ua435
- Parent Record(s):
- 23d738ba88f8333bc39725f9cb5bd0b8, 83d7d84d4a906b77a877f50ccddf0ccd, and ef456d2a6c943c510d5169405dfd9416
- Description:
- 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
- Date Created:
- 1987
- Collection:
- System Dynamic Society Records
- Collecting Area:
- University Archives
- Collection ID:
- ua435
- Parent Record(s):
- 23d738ba88f8333bc39725f9cb5bd0b8, 83d7d84d4a906b77a877f50ccddf0ccd, and ef456d2a6c943c510d5169405dfd9416
- Description:
- 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.