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- Type:
- Document
- Date Created:
- 1991
- Collection:
- System Dynamic Society Records
- Collecting Area:
- University Archives
- Collection ID:
- ua435
- Parent Record(s):
- 23d738ba88f8333bc39725f9cb5bd0b8, 5d7e83a7ca6c4cd9ab0ccc8a805a7aa7, and d1cfc0fcedb4f6334f34d1ca11dcf292
- Description:
- Formulation of the general scheme for developing dynamic models of macrosystems with selfreproduction and resources exchange, using the local equilibria principle, is proposed. Regional system, where reproduction and exchange processes have significantly different relaxation times, is considered. The model of regional system, where dynamic exchange processes are described as the evolution of local stationary states, is presented. Calculation, classification and bifurcation of equilibrium points of regional dynamics are studied. Results of computational experiments are given.
-
- Type:
- Document
- Date Created:
- 1991
- Collection:
- System Dynamic Society Records
- Collecting Area:
- University Archives
- Collection ID:
- ua435
- Parent Record(s):
- 23d738ba88f8333bc39725f9cb5bd0b8, 5d7e83a7ca6c4cd9ab0ccc8a805a7aa7, and d1cfc0fcedb4f6334f34d1ca11dcf292
- Description:
- This paper discusses the modeling problem for the economic development of the old industrial cities in China . A system dynamics model is applied to analyse the recessionary causes of the old industrial cities, and find the possible strategies of the technical progress and economic development in future. The paper gives the simulation results of an example, and discusses the system structure with adding policy loops in the causal diagram.
-
- Type:
- Document
- Date Created:
- 1991
- Collection:
- System Dynamic Society Records
- Collecting Area:
- University Archives
- Collection ID:
- ua435
- Parent Record(s):
- 23d738ba88f8333bc39725f9cb5bd0b8, 5d7e83a7ca6c4cd9ab0ccc8a805a7aa7, and d1cfc0fcedb4f6334f34d1ca11dcf292
- Description:
- The feedback control concept is central to both modern control theory and system dynamics. Several attempts have been made to utilise modern control theory in developing some formalised procedures for system dynamics models. Some studies on the application of control theory to a simple production-inventory system have been reported. These studies were able to discover some important policy decisions to improve the behaviour of the system. This paper presents an alternative procedure based on modal control theory for designing useful policies for the production-inventory system. The results obtained in this study are generally similar to those obtained in earlier studies reported in the literature.
-
- Type:
- Document
- Date Created:
- 1991
- Collection:
- System Dynamic Society Records
- Collecting Area:
- University Archives
- Collection ID:
- ua435
- Parent Record(s):
- 23d738ba88f8333bc39725f9cb5bd0b8, 5d7e83a7ca6c4cd9ab0ccc8a805a7aa7, and d1cfc0fcedb4f6334f34d1ca11dcf292
- Description:
- The relationship between foreign capital inflows, the build-up of debt, and economic growth in a developing country are analyzed using a system dynamics model of the pertinent processes. The Philippines serves as an empirical case to apply the model. The model incorporates the macro-structure of economic growth, the micro-structure of market-clearing mechanisms, and an accounting of the money flows. The study shows that economic policies enhancing debt-servicing ability create better economic performance than those limiting loan giving. Increasing capital-intensity is the most important part of such policies. They are further facilitated by encouraging investment through decreasing taxes and enhancing demand through increasing government spending and promoting exports. Thus, augmentation of domestic resources by foreign capital inflows appears to be a viable economic strategy.
-
- Type:
- Document
- Date Created:
- 1991
- Collection:
- System Dynamic Society Records
- Collecting Area:
- University Archives
- Collection ID:
- ua435
- Parent Record(s):
- 23d738ba88f8333bc39725f9cb5bd0b8, 5d7e83a7ca6c4cd9ab0ccc8a805a7aa7, and d1cfc0fcedb4f6334f34d1ca11dcf292
- Description:
- Interacting populations of bacteria and phages (i.e. vira) play an important role for many biotechnological applications. The homogeneous and well-controlled bacterial cultures used in modern cheese production, for instance, are often extremely sensitive to attacks by phages, and considerable efforts are invested in the search for more resistant cultures.In order to examine different strategies in this search we have simulated a variety of growth, competition and selection processes that may arise in interacting populations of bacteria and phages. Our model considers a culture containing several variants of the same bacterium, each sensitive to a specific phage. The culture grows in a chemostat with a continuous supply of nutrients. Surplus bacteria and vira are removed through dilution. Depending on the rate of dilution, the model exhibits periodic behavior, quasiperiodic behavior, deterministic chaos or hyperchaos.To study phenomena related with incomplete mixing in the chemo state we have coupled behaviors associated with different compartments. In particular, we have investigated how the behavior changes when we introduce a diffusive coupling of a periodic attractor to a quasiperiodic and a hyperchaotic attracter, respectively.
-
- Type:
- Document
- Date Created:
- 1991
- Collection:
- System Dynamic Society Records
- Collecting Area:
- University Archives
- Collection ID:
- ua435
- Parent Record(s):
- 23d738ba88f8333bc39725f9cb5bd0b8, 5d7e83a7ca6c4cd9ab0ccc8a805a7aa7, and d1cfc0fcedb4f6334f34d1ca11dcf292
- Description:
- System Dynamics is one the methodologies for behavioural research. Some of the important steps for the behavioural analysis under system dynamics framework are system conceptualization, model fabrication, model simulation and finally the policy analysis. Out of these steps model simulation usually involves massive computation and hence it may necessitate usage of the computers. When it is a question of the usage of computers there is a need of a language for computer oriented model preparation and simulation. To cater to this need a software viz. DYSBASE (DYNAMIC SIMULATION WITH DATA BASE) has been developed. This paper chalks out an overview of DYSBASE. The language syntax and the operational procedure of DYBASE software is described in the DYSBASE manual available with the authors.
-
- Type:
- Document
- Date Created:
- 1991
- Collection:
- System Dynamic Society Records
- Collecting Area:
- University Archives
- Collection ID:
- ua435
- Parent Record(s):
- 23d738ba88f8333bc39725f9cb5bd0b8, 5d7e83a7ca6c4cd9ab0ccc8a805a7aa7, and d1cfc0fcedb4f6334f34d1ca11dcf292
- Description:
- The proposed model is a scientific attempt to apply the methodology of System Dynamics to research one of the most complex organization system of management, with the aim of finding out the most suitable scenario of the management by economic migration flows. The problem of economic migration is one of the most important problems both for the countries of origin and for the receiving countries. Computer simulation of the proposed model confirms most of the results achieved by Andre Sapir, but pointing to the possibility of multilateral consultation of the managers of the regional system, as well as of the society to which it belongs, in this case: REPUBLICA of CROATIA, and the managers of the countries which absorb the economic migrations flows. The result of these multilateral consultantions would be very useful for the countries of origin, and for the countries that receive economic migrants as well!
-
- Type:
- Document
- Date Created:
- 1991
- Collection:
- System Dynamic Society Records
- Collecting Area:
- University Archives
- Collection ID:
- ua435
- Parent Record(s):
- 23d738ba88f8333bc39725f9cb5bd0b8, 5d7e83a7ca6c4cd9ab0ccc8a805a7aa7, and d1cfc0fcedb4f6334f34d1ca11dcf292
- Description:
- This paper tries to examine information generation properties of the network structure usually shown by arrows and nodes by the dynamic simulation analysis. The information generation means the augmentation of information stock (we call “base”) of the network brought up by the network members. We introduce behavioral aspects into the analysis. In the past several researchers have approached to the task performances of the network structures by the experimentations involving actual persons. Our research puts emphasis on the information base on which tasks are accomplished. Therefore we will not touch the performances of achieving tasks explicitly. Our objectives are to examine how the structure of network has influences on the information base for accomplishment of tasks by its communication channels stipulated by the structure.
-
- Type:
- Document
- Date Created:
- 1991
- Collection:
- System Dynamic Society Records
- Collecting Area:
- University Archives
- Collection ID:
- ua435
- Parent Record(s):
- 23d738ba88f8333bc39725f9cb5bd0b8, 5d7e83a7ca6c4cd9ab0ccc8a805a7aa7, and d1cfc0fcedb4f6334f34d1ca11dcf292
- Description:
- Energy dissipative systems are considered through a general approach. The one direction non-steady state equation for mass, heat and momentum transport shows that the energy used by system could be considered through “energy dissipation function”, comparable to the “wave function” used in Quantum Mechanics. A complex time scale is proposed. This permits to consider the fluctuations as being in a time scale which is different from our classical one. The non commutation of operators of the basic equation introduces quantification which supports the use of finite different equations instead of a differential equation. A discretized Chaotic Process is proposed as a model for actual systems. The example of a fluidized bed shows that quantum considerations through a ground dynamic state and an excited state could support the above proposal which is in agreement with the actual qualitative behaviour. The Chaotic Process can be put in agreement with the thermodynamics based principle when comparing the minimum energy dissipation of the actual system.
-
- Type:
- Document
- Date Created:
- 1991
- Collection:
- System Dynamic Society Records
- Collecting Area:
- University Archives
- Collection ID:
- ua435
- Parent Record(s):
- 23d738ba88f8333bc39725f9cb5bd0b8, 5d7e83a7ca6c4cd9ab0ccc8a805a7aa7, and d1cfc0fcedb4f6334f34d1ca11dcf292
- Description:
- Innovation management is a special task in several respects. Its success is essential for the survival of the firm. It deals with highly dynamic processes, and it requires a viable strategy from the very outset. Analyses of innovation dynamics have shown that market forces usually do not allow the search for a gradual approach towards a successful strategy. Frequently technology advances rapidly and the market changes so fast that no second try is possible.In such a situation, the artificial reality of a management simulator provides a powerful environment to learn about the system under investigation. It allows deeper insights into the problem situation. In its virtual world, it alleviates the development of an improved understanding of the intrinsic aspects, and leads to a better feeling for possible reactions of the market.The paper presents the coarse structure of an Innovation Management Simulator (IMS). The players represent four competing companies. At the beginning of the simulation, all offer a comparable product, no firm holds a competitive advantage. Among other policies, they can -through resource allocation for research and development - create additional, non substituting products. The product life cycles with their time patterns of profits and sales, market shares, etc. are endogenous variables, influenced by the players’ actions.The decision to develop and launch a new product and the choice of the time for market entry are strategic variables of the players. Further decisions are required to budget product and process development, pricing and advertising, capacity allocation, personnel recruitment and financing. The game is played on a quarterly basis. The decisions are fed into a System Dynamics model, and the results provide the input for a new round of decision making.