Busy lines are a persistent and persuasive problem common to all telephone systems, whether it counts with the most advanced digital technology and network management or no, there will always be a period during the day on the week where telephone calls cannot be completed due to busy line with the resultant loss of revenue. If expansion programs for telephone lines were not in accordance to actual demand growth telephone calls, this problemwill grow to the point where retrials would seriously impairthe telephone system operation. This paper describes the use of a system dynamics model for designing and evaluating expansion policies that respond to actual demand and ameliorate problem.
In a world of increasing complexity and turbulence organizations run the risk to loose effectiveness as well as efficiency when managed on the base of linear thinking and shortsighted decision making. System thinking and organizational learning instead will become a prerequisite for competitiveness and survival.
Population is an element in the social system. There are a number of elements in the social systems which will influence the population growth rate. On the other hand, population growth will, in turn, exert influence on other social elements. We can, therefore, apply the system dynamics (SD) model to dealing with the problems of population control. This paper, based on the investigation carried out in Anhui Province of China, conducts a study of the policies concerning population control in China by use of the system dynamics model.
The coordination in industrial systems should be one of the major challenges for future competitive advantages. The issues of industrial system’s coordination have been studied in system dynamics at the very beginning of the field. However, system dynamicists had not put enough efforts to study the industrial “systems”. This paper attempts to use system dynamics approach to study the “dynamics complexity” issues in industrial systems. The Center-Satellite System simulation game (CSS game), which based on Taiwan’s center-satellite industrial system (a huge industrial system with over 120 Center-factories, each with up to 400 networked Satellite-factories) was developed. Future research directions are discussed.
Recent research in the field of System Dynamics has been concerned with defining archetypal structures by which toclassify insights in dynamical systems. For example, Richmond has proposed both infrastructure and activity archetypes, whereas Senge has defined eight relevsnt generic structures. Additionall,Wolstenholme has defined a number of management situations as being made up of actual outcomes which are opposed to those intended.
What is the relative importance of internal versus contextual forces in the birth and death of scientific theories? Elaborating on the analysis of a model of multiple paradigm competition and scientific development already developed by Wittenberg and Sterman, we find that situational factors present when a paradigm is launched largely determine a paradigm’s probability of rising to dominance. Stronger paradigms that survive the emergence phase live longer than their weaker counterparts, but this too is contingent upon factors present during the emergence period.
This article concerns the problems that junior college students encounter when trying to understand and utilize the concept and insights traditionally provided by the teaching of mathematics. In this context, the concept “change” is significant because it is closely associated with the ‘derivative” and the "integral” defined in mathematical analysis.
The author explores a comprehensive methods of system analysis, inference and synthesis and model sets for studying complex system. These methodologies and model sets can be used in studying the development strategy and planning of socio-economic-ecosystem. It has been successful in the study of Pudong Economic Zone of Shanghai.
Based on system dynamics, this paper creates an approach of combining qualitative and quantitative analyses, systems thinking, system analysis, synthesis and deduction with a set of models. First, We build up a generic model set with various economic indexes. About several dozen modern management methods have been applied to the different subsystems implied by their parameters and feedback structures.
In recent years many system dynamics modelers have pointed out that for effective implementation of model results it is that the client participates in the model-building process. This has lead to various more or less successful approaches in group model-building. However, up to now little systematic research has been conducted in the area of effectiveness of group model-building. Systematic evaluation of group model-building is important in order to a) understand how clients and organizations are effected by group model-building; and b) improve the effectiveness of the group model-building proces. In this paper evaluation results are presented of four model-building projects based on clients' opinions of the successfulness of these projects.
This paper presents one middle term simulations model and its main results. We chose the production systems which produce complex capital goods, for example electrical equipement or household goods. The objective of this type of system is to build up stocks of finished goods which are put at the disposal of the customers. The corresponding macro model was designed by a systemic vision and split into three components which represent the operating, decision and information production sub-systems. The simulation of the generic model has permitted the improvement of system dynamics knowledge. We detected prominent decision loops and some unnecessary loops in production control.
Fuzzy numbers is presented as an alternative to probabilistic methods for the management of uncertainty in system dynamic model. Fuzzy numbers are particularly suitable to represent vagueness and qualitative values. Fuzzy numbers are used during simulation, but due to interactiveness among variables there is a need for global optimization methods. Some examples that illustrate the use of fuzzy numbers, both directly and as a means to represent qualitative values, are shown.
This paper explores the behavior of the gross investment considerig the linear versions and two non-linear versions from Kalecki’s model. This model assumes that there is an average gestation lag of investment and it is formuled by means of a mixed differential-difference equations.
This paper examines the use of a system dynamics modelling technique to enhance the contribution made by cash flow forecasts to decision makers' mental models. It is argued that by making explicit and accessible the dynamic complexity in cash flow relationships, systems dynamics can provide valuable insights for decision making puposes. By permitting the exploration of behavioural responses to perceptions about the financial position of thee business, a richer picture of the decision outcome is developed leading to changes in decision makers perceptions about the riskiness of a proposed course of action. A case study of a commercial organisation is used to illustrate these insights.
Service quality cannot be measured and tested in as straight forward a manner as in manufacturing. This biases serve businesses to focusing on keeping measurable variables-typically, expenses and work flows-in control, while underinvesting in the intangibles of service capacity and service quality. In the long-term, results can be mediocre levels of service quality, poor customers satisfaction, high turnover of service personnel, and ultimately, higher total costs. In this paper we will present an emerging theory of interactions between Service Quality and Service Capacity, relate this theory to past research in both the System Dynamics and Total Quality Management traditions and outline ongoing empirical testing of the theory.
What should every professional dynamicist know? What are the core works defining our field? This survey of the English-language system dynamics literature identifies and summarizes one view of the essential papers, book, games and software programs that have influenced the development of the field. Such a list serves as a means of reflecting on the foundation of current research and practice, thus providing a catalyst for a continuing discussion among system dynamicists on the major themes of the field and the contributions that define them. In presenting this bibliography, the authors encourage other researchers., practitioners and student to add their views to the present effort.
This Paper develops a conceptual model of a collegial system working without external adjudication or an institutional charter governing the conduct of its operations. The model is applicable to many of the academic and research organizations established in the developing countries, which have attempted to emulate the equivalent professional organization in the advanced industrial countries but have achieved low efficacy. The analysis suggests that an unadjudicated collegial system is not sustainable, for it will tend to create an authoritarian administration which will impair the collegial norms and misallocate scarce resources to the activities fueling bureaucratization and expansion of administrative scope, while professional autonomy, innovativeness and self-actualized behavior are suppressed. Professional conduct tends to be more-value rational than the bureaucracy since it is subject to reviews by external peers. Thus, legitimation of referent power is essential to creating value-rational decisions which assure a balanced resource allocation that sustains a collegial system. Limiting scope of the administration through an external scrutiny of its conduct or a charter appears to facilitate this process.
The purpose of this paper is to show that a well-known group of economists known as “Post Keynesians” or “Post Keynesian Institutionalists”, engage in macroeconomic modeling in a way that is strikingly similar to the system dynamics method. It will be argued, therefore, that system dynamics can be used to improve Post Keynesian macroeconomic analysis. In addition, this paper will present an original system dynamics model of macroeconomic growth, instability, and income distribution, that can clearly be classified as Post Keynesian. Of interest is that the model generates, among other behaviors, an economic long wave.