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- Type:
- Document
- Date Created:
- 1985
- Collection:
- System Dynamic Society Records
- Collecting Area:
- University Archives
- Collection ID:
- ua435
- Parent Record(s):
- 23d738ba88f8333bc39725f9cb5bd0b8, 8cc5e98280358f60c3a33cc99e75a20e, and 11576afb39e5cd4a779a3912c119ca81
- Description:
- In this paper we review the algorithm to identify the type of variables (levels, rates, auxiliaries) which appear in the influence diagram. This algorithm has been implemented on a personal computer at the Cagliari University.
-
- Type:
- Document
- Date Created:
- 1985
- Collection:
- System Dynamic Society Records
- Collecting Area:
- University Archives
- Collection ID:
- ua435
- Parent Record(s):
- 23d738ba88f8333bc39725f9cb5bd0b8, 8cc5e98280358f60c3a33cc99e75a20e, and 11576afb39e5cd4a779a3912c119ca81
- Description:
- There has been a great deal of work done in the simplification of linear dynamic models. Given that most models that are in use are nonlinear this has restricted the applicability of the available techniques. By concentrating on a particular nonlinear phenomenon, in this case shifting loop dominance, it is possible to use the techniques of linear analysis for the simplification of nonlinear models. The theory for this is developed and it is shown how this can be applied to the model. For purposes of exposition the market growth model is used and the results are encouraging. Though there is still a good deal of work to be done it seems feasible to develop simplification techniques for nonlinear models that address directly the nature of the nonlinearities.
-
- Type:
- Document
- Date Created:
- 1985
- Collection:
- System Dynamic Society Records
- Collecting Area:
- University Archives
- Collection ID:
- ua435
- Parent Record(s):
- 23d738ba88f8333bc39725f9cb5bd0b8, 8cc5e98280358f60c3a33cc99e75a20e, and 11576afb39e5cd4a779a3912c119ca81
- Description:
- Much of the work done in system dynamics has been criticized for making insufficient use of statistical estimation techniques. There have been various responses to this criticism concentrating on the other sources of information available to the model builder. One of the major hurdles to the use of statistical estimation techniques is an understanding of when they are likely to be useful in system dynamics modeling. In this paper we consider different estimation techniques and how useful they can be in system dynamics modeling. The work is meant to be a practical guide that will allow the modeler interested in statistical estimation to gain some understanding of the different approaches available. We concentrate or attention to the special problems that the system dynamics modeler is likely to encounter in estimation.
-
- Type:
- Document
- Date Created:
- 1985
- Collection:
- System Dynamic Society Records
- Collecting Area:
- University Archives
- Collection ID:
- ua435
- Parent Record(s):
- 23d738ba88f8333bc39725f9cb5bd0b8, 8cc5e98280358f60c3a33cc99e75a20e, and 11576afb39e5cd4a779a3912c119ca81
- Description:
- Studies of deterministic systems which apparently exhibit chaotic behavior are attracting much interest in disciplines ranging from physics to economics. A particularly interesting case of a simple electrical network has been studied recently in the physics literature with the objective of isolating minimal characteristics essential to chaotic behavior. A system dynamics formulation has been given to the numerical simulation of this system. Instructional laboratory exercises comprising both observations on the electrical circuit and computer simulation of the circuit are being implemented for the upper level undergraduate and graduate students.
-
- Type:
- Document
- Date Created:
- 1985
- Collection:
- System Dynamic Society Records
- Collecting Area:
- University Archives
- Collection ID:
- ua435
- Parent Record(s):
- 23d738ba88f8333bc39725f9cb5bd0b8, 8cc5e98280358f60c3a33cc99e75a20e, and 11576afb39e5cd4a779a3912c119ca81
- Description:
- The Jutland Technological Institute (JTI), Aarhus, Denmark, has embarked a project to promote the utilization of System Dynamics models in Danish Industries. The vehicle of this projekct is a new type of hybrid computer, the MOSES (Modular Symbolic Electronic Simulator) system, developed at the Technical University of Denmark. In ongoing projects the MOSES system has demonstrated itself as an invaluable “discussion” partner. We have performed a series of seminars with managers from medium and large sized Danish companies. At these seminars some of the generic structures of growth companies have been discussed and related to Danish conditions. This report contains a brief description of the MOSES system and a description of the ongoing project.
-
- Type:
- Document
- Date Created:
- 1985
- Collection:
- System Dynamic Society Records
- Collecting Area:
- University Archives
- Collection ID:
- ua435
- Parent Record(s):
- 23d738ba88f8333bc39725f9cb5bd0b8, 8cc5e98280358f60c3a33cc99e75a20e, and 11576afb39e5cd4a779a3912c119ca81
- Description:
- This is a report of several applications of System Dynamic Methodology to banks, with particular emphasis given to their structure and their Decision Making in terms of System Dynamic concepts. Aplications range from policy design and long term planning to the design of Decision Support systems. The first part presents relationships between money flows and accounting information. Next, some policy design results are presented. Later on, the estimation of the parameters of the SD model is transformed into the heart of a Decision Support System.
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Fritz, Richard G., "Economic Development and Financial Deepening: A Study of Causation and Dynamics"
- Type:
- Document
- Date Created:
- 1985
- Collection:
- System Dynamic Society Records
- Collecting Area:
- University Archives
- Collection ID:
- ua435
- Parent Record(s):
- 23d738ba88f8333bc39725f9cb5bd0b8, 8cc5e98280358f60c3a33cc99e75a20e, and 11576afb39e5cd4a779a3912c119ca81
- Description:
- The direction of causality between financial deepening and economic development is tested. Using factor analysis, two indexes are developed to represent the two economic phenomena for the Philippines. Time series causality tests are used to evaluate the direction of causality. The results indicate the causal pattern reverses over the history of the sample. Reversal is viewed as the result of financial repression. The structural dynamics implied by the empirical time series test is evaluated using a system dynamics model. The growth promoting and growth inhibiting roles of the financial sector are simulated in the dynamic structure of a dynamic economic development model.
-
- Type:
- Document
- Date Created:
- 1985
- Collection:
- System Dynamic Society Records
- Collecting Area:
- University Archives
- Collection ID:
- ua435
- Parent Record(s):
- 23d738ba88f8333bc39725f9cb5bd0b8, 8cc5e98280358f60c3a33cc99e75a20e, and 11576afb39e5cd4a779a3912c119ca81
- Description:
- A representation of socio-economic systems using reduced models allows a “qualitative” type of analysis to be carried out. It is often the case, especially in the long term process, that the main interest is directed towards the asymptotic behavior of the solutions as a function of the initial state and to evaluating the properties of stability of stationary states. In this article, after a short outline of the procedure and methodology adopted, we describe the application of these techniques in the construction and use of a dynamic model for the design of a tourist village. The model, which mainly deals with the impact of man on the environment, serves to evaluate the social and economic effects of the construction of a tourist centre in a national environment which must be conserved.
-
- Type:
- Document
- Date Created:
- 1985
- Collection:
- System Dynamic Society Records
- Collecting Area:
- University Archives
- Collection ID:
- ua435
- Parent Record(s):
- 23d738ba88f8333bc39725f9cb5bd0b8, 8cc5e98280358f60c3a33cc99e75a20e, and 11576afb39e5cd4a779a3912c119ca81
- Description:
- Power demand forecasting methodologies which are currently being used by electricity authorities are end use method, trend method and Scheer's formula. These methodologies being static in nature, do not take into account the future power supply position, while becoming an important instrument of economic change the growth of power generation activity itself is totally dependent upon the overall economic development thus forming an important feedback loop in the economic system. Present paper discusses a power economy system dynamic model for estimation of future demand and supply position of Power.
-
- Type:
- Document
- Date Created:
- 1985
- Collection:
- System Dynamic Society Records
- Collecting Area:
- University Archives
- Collection ID:
- ua435
- Parent Record(s):
- 23d738ba88f8333bc39725f9cb5bd0b8, 8cc5e98280358f60c3a33cc99e75a20e, and 11576afb39e5cd4a779a3912c119ca81
- Description:
- The paper is an attempt at a theory of relations connecting feasible observations/ or measurements/ and feasible decisions/ or controls/ in general cybernetic systems. The theory gives a formal framework and a tool for quantitative analysis of the following facts: 1. An increase in observation possibilities, e.g. an increase of the precision of measurement, enlarging the scope of observation etc., results in an increase in decision possibilities by making more effective decisions possible. This works also in the other direction: if there are more feasible decision, new observations or measurements become available. 2. In the framework of a cybernetic model no decisions and/or observations which generate antinomies can be simultaneously feasible. This creates interesting and important constraints on measurements and decisions in systems which include man or where a human or automatic decision maker is an object of observation, and where the results of observation may be known to this decision maker. 3. The observation/measurement/ takes tome and changes its object and thus the result of observation always refers to past rather than to the present. This normally is due to physical effects through other phenomena, like psychological, may also be important depending on the nature of the object. The facts of group 1 are in a sense opposite to those of groups 2 and 3. This leads to the existence of optimum decision-measurement possibilities. Conditions for this optimum to exist together with its significance for biological and technological system will be discussed. The subject of this paper is of interdisciplinary interest and has been studied, partially and from particular angles, within the framework of control theory/facts of group 1/, mathematical logic/theory of antimonies, principles of mathematics-mainly facts of group 2/, physics/theory of measurement, principles of quantum machanics-mainly facts of group 3/ and philosophy/the classic problems of free will and consciousness/. The relevance of the presented theory to these fields will also be discussed.