The term ecosystem structure has been variously defined in the ecological literature. I prefer to use the definition proposed by Margalef (1963) Ecosystems have a structure, in the sense that they are composed of different parts or elements, and these are arranged in a definite pattern. For the purpose of this study, I define ecosystem structure as including the elements of the system (Odum 1962), the structure of their interactions (network design- Hill and Wiegert 1980), and the particular form of interactions (instantaneous flow rates- Hill and Wiegert's form). The structure of an ecosystem determines its behavior and functional attributes, including both nutrient recycling and ecosystem maturity, I hypothesized that certain ecosystem characteristics tend to co-occur based in similar casual factors in the underlying ecosystem structure. The purpose of this study was to test the hypothesis that tightening of the phosphorus and carbon cycles increases the stability of pelagic ecosystems to nutrients perturbation.
Many trends in computing- distributing processing, telecoms, reliance on computing for key business processes- combine to increase greatly the risks and vulnerability of firms to computer attack. The form of attack is also is also diversifying- mischief-making by "hackers" or virus writers, sabotage by disgruntled employees, fraudulent activity, or simple random hardware or software failure. The threats and potential costs to firms of breakdowns in security can be very large, involving the need to replace or re-engineering systems, to recover or reconstruct key information and data, and maybe even to try to re-establish goodwill with customers who may have been affected. The literature reflects that while the general issues here are appreciated, few firms understand fully the potential threats to their business, nor have explicit policies and procedures to guard against them.
Learning curves have been identified in a wide variety of industries (Dutton and Thomas, 1984) and the extensive theoretical literature has explored their strategic implications A learning curve creates a positive feedback loop by which a small initial market share advantage leads to greater production experience, lower unit costs, lower prices and still greater market share advantage. In general, the literature suggest that in the presence of learning curves - and when learning is privately appropriable-firms should pursue an aggressive strategy in which they seek to preempt their rivals, expand output and reduce price below the short-run profit maximizing level (Spence, 1981: Fudenberg and Tirol, 1983, 1986; Tirole, 1990). Intuitively, such aggressive strategies are superior because they increase both industry demand and the aggressive firm's share of that demand, boosting cumulative volume, reducing future cost and building sustained competitive advantage until the firm dominates the market. The desirability of aggressive strategies in industries with learning curves have diffused widely with business education, the popular business literature management texts, and public policy debates. (Rothschild 1990, Hax and Majluf, 1984; Oster, 1990; Porter, 1980; Krugman, 1990) and learning curve strategies appear to have led to sustained advantages in industires such as synthetic fibers, bulk chemicals, and disposable diapers (Shaw and Shaw 1984; Ghemawat 1984, Porter 1984), However in many industries including televisions, VCRS, semiconductor, toys and games, lighting equipment, vacuum cleaners, aggressive pricing and capacity expansion have led to substantial overcapacity and price wars that have destroyed industry profitability (Beinhocker, 1991; Salter, 1969: Porter 1980; Saporito. 1992; The Economist, 1991; Business Week, 1992).
Why are quality so successful in some firms but not in others? Some point to difficulties in implementation or leadership. The problem is more fundamental, however. Quality programs are tightly coupled with other functions, routines, and structures. Product development, marketing, accounting, systems, human resource policies, employee morale, pricing policies, and financial results are all affected by and in turn influence quality initiatives. We hypothesize that the productivity gains from successful quality programs can interact unfavorably with existing routines and structures. Under certain conditions these interactions may lead -or force-a firm to take actions that ultimately cause the demise of an otherwise successful program. Field study and formal models are used to test these hypotheses.
We apply a dynamic time-series method called Vector-autoregression (VAR) to studying the dynamic linkage between unemployment and crime rates in Virginia. The promise of the VAR methodology lies in its ability to provide information on the dynamic and the feedback properties in systems of variables.
As Simon points out (1969), to design is a purposeful activity aimed at changing a current situation into a desired one. When the entity to be designed is a human organization, then the current situation, the desired situation and the resultant design can't be clearly defined. Consequently, we can't adopt an optimization approach in the organizational design. To design an organization implies to develop a process of gradual understanding about our current situation, about our expectations regarding ideal situation and about the way to intervene, through design, in the organization. Moreover, this activity of organizational understanding and action goes with the organization during all its life. Therefore, organizational design, viewed as a permanent activity of understanding and action, could be recognized as a process of organizational learning.
Long term explorations (15 to 40 years ahead) of the future development in travel demand are fraught with uncertainties. In particular, in long term policy development it is essential to use comprehensive and consistent scenarios and to incorporate the essential factors, constraints and feedback mechanisms in the analysis. It is on the long term that complexity arises because many of the usual assumptions on steady conditions on the short term are not valid. Moreover, long term developments in society which determine travel demand are hard to predict. It is no surprise that there is little consensus among the professionals on an adequate concept for the passenger transport system which is valid on the long term.
The new liberalism and privatisation trends now taking place world-wide have influenced government policies on electricity utility management. Some countries in the Latin America region are moving away from central planning, vertically integrated regional monopolies and heavy biased hydroelectricity generation schemes towards more liberalised set ups. The specific structure chosen in the Colombian case have important variations with respect to those advocated by main stream economic thinking. Recent technology developments or power generation and extensive gas use in the household sector have stretch further relationships between electricity and gas industries. In this paper we present a System Dynamics model specially built as part of larger projects to study and asses the effect of market forces into the power generation sector, at the light of a larger scale plan which intends to supply natural gas as an important portion of the household sector and the power generation industry. With the aid of the model, we examine a number of economic signals to induce capacity investment to secure appropriate reserve margins for the Colombian electricity system.
System Dynamics Education (SDE) efforts have been underway in the Unites States since the 1970s. Since then Pre-collegiate educators have attended Systems Dynamics (SD) conferences, participated in training workshops, developed and distributed curriculum materials, launched projects, published articles and complete dissertations. In October 1995, the authors have interviewed teachers and administrators involved in SDE projects, analyzed curriculum materials, and reviewed the literature. Based on this data, strengths and weakness within the SDE field has been identified, and recommendations have been developed. This paper is a progress report intended to promote dialogue among those interested in SDE. We encourage others to challenge these recommendations and substitute alternative ones.
A system dynamic approach is applied to explore sociological dynamics on rural community development of a traditional rural in Indonesia namely Wamena. The model is used to explain the causalities relationship of the decision making process of rural communities in responding to the development implemented by the government. The model consists of five main sectors: native population, migrant population, land, food, and agricultural technology. The simulation shows that the dynamics of development pattern is greatly influenced by the interactions of natives and migrants in market activities.
Management of scarce water in Jordan requires development and operation of expensive water facilities and making hard policy decisions. System Dynamics is used to represent the structure of the water sector in Jordan and to test potential policy decisions and water development scenarios. This paper discusses the potential use of System Dynamics simulation models to serve as tools to aid water managers and policy makers in making management decisions and long-range water strategies.
In spite of its potential strengths and different attempts made in the past to apply it to business research, management education and practice, still today System Dynamics is far from being sufficiently exploited both in academic and in industrial context in Italy. System Dynamics-Italian chapter born offers the opportunity to: Investigate the present S.D. scenario in Italy; University and research centers where S.D. courses are present, Companies where there have been or are having experiences with S.D. methodology, Practical applications by consultants in both educational and company model construction, Underline problems met proposing S.D. approach, Express practical results obtained, Evaluate potential "levers" for S.D. diffusion.
On behalf of the "product portfolio" analysis through Boston Consulting Group (B.C.G.) approach and System Dynamics methodology analysis of a wine production firm, a dynamic model of a company had been developed. The winery model is designed for different functions of the firm, taking in to account Resource & Production, Economic & Financial and Market subsystems. Even though the model has been focused to evaluate different market strategies in new product launching, it can be used also to support simulating policies concerning different management functions of the firm. The model will be described schematically and a series of simulation results will be presented, particularly in evaluating company policies in new product launching, so to put in evidence how system dynamics could be useful in strategic analysis.
ASIMOV (Autopoiesis Simulation Model for Valuation) was developed in the context of an applied research project on Small and Medium-sized Enterprises (SME), and is a simulation model for the behaviour of an innovative company in a market characterised by rapid change. The model is based on two elements: the nucleus and the membrane. The nucleus represents the operational strength of the company: the membrane its capacity for interaction and exchange with the outside world. Special attention is paid to the membrane for the effects of telematics, particularly telework. In fact, the model is intended as a predictive instrument for the implementation of types of telework. The purpose of ASIMOV is to make forecasts regarding the nucleus-membrane dynamics that take place in companies after an investment in an observable and partly predictable market. With a three-year time horizon in the simulation it is possible to consider most phenomena. The simulation model developed with high Performance Systems Inc.'s ITHINK, is parametric, allowing it to adapt quickly to specific situations at reasonable cost.
Japan has made a remarkable progress not only in the area of the economic development but also in the area of the pollution control after the world war the second; This paper, firstly tries to make analysis of Japanese pollution policies to the mainly atmospheric problems and to fix the specified Japan Environmental Model of the atmosphere during this forty years, secondly to make the recommendation of the importance of the application of the advanced technologies to the transitional environmental issues.
Management is about action designed to bring about change in some situation. Any sane management action implies the manager holds: 1. a representative mental model of the current situation and an understanding of why it has to change, 2. an acceptable and feasible mental model of the desired changed situation and an understanding of why it is more desirable that the current situation, 3. a representative mental model of how the world works in the particular situation under consideration that, and 4. a belief that the situation can be improved through management action.
Economics is a discipline rich in models designed to elucidate the behavior of potentially complex economic processes. The reduction of complex processes to analytically solvable models, however shifted focus away from the spatio-temporal dynamics representative of economic processes, and excluded to a significant extent experimentation from these processes (Allen 1988, Ruth 1993) In the illustrations below, special attention is given to three issues that are found at the sidelines of traditional economic analysis (Hannon and Ruth 1994, Ruth and Hannon, in press). The first of these issues concern the dynamics of economic system on their way to equilibrium points. The second is the spatial context within which economic activity takes place. The third are temporal and spatial discontinuities of economic processes.
In this paper we will study a production line operating under a Constant Work In Process (CONWIP) control System Dynamics and discrete simulation. The goal of our research is to determine whether various characteristics of a production line can be better understood using System Dynamics or discrete simulation. The software used in our investigation is VENSIM for System Dynamics and WITNESS for discrete simulation. In conclusion we have found that the best way to manage the production line is using both approached in a complementary manner.
Most system dynamics aims to support strategic decision making. Since the first evaluation studies of the actual impact of models on decision making appeared in the 1970s, the factors influencing effectiveness have become increasingly clear. As a result, in addition to development and analysis of models, the communication of recommendations to policy makers has become a major focus of the system dynamics community. Often, this communication takes the form of direct involvement in the modeling, efforts, resulting in Group Model Building. Simultaneously with the introduction of system dynamics the concept 'mental model' was proposed as an important variable influencing decision making. Recently, this concept was criticized as being pre-scientific and for the most part undescribed and unmeasured (Richardson et al, 1994) Richardson et al. see 'operator logic' as the intervening concept between managers' behavior and modeling projects. In a case study of the effects of Group Model-Building (Vennix et al, 1996) an alternative construct was proposed, i.e. 'the intention to perform a behavior'. Both of these proposed constructs illustrates the need for a better understanding of the relationship between model-building on one hand, and cognition and behavior of managers involved in model-building, on the other hand.
Demands on students to learn complex, higher order skills have raised questions about the schooling environment in which they would most likely learn them. Answers to such questions have come from many fields, and have suggested practical solutions to many problems we are experiencing in transforming the Falmouth schools. Social learning theory (Albert Bandura) suggests that copying can lead to significant learning. We describe a set of activities and facilities that stimulate all schooling stakeholders (teaching, students, parents, administrators, future employers, etc.) to engage in and can be seen performing the higher-order behaviors we want students to learn. Operational research (Stafford Beer) suggest that organized information on its inputs, operations and outcomes. We describe a process for engaging each school subsystem in modeling its operations and contributions to the school's goals, and a facility for displaying organized information and operational models in a Performance Information Center (the PIC) for the decision-makers in each schooling sub-system.
This paper describes a project we have conducted in the software industry. The client's department involved in the project can be described as a newly established department performing software factory-like activities. The client's expectations of the department is anticipated (in terms of amount of personnel, numbers of orders, etc.) However, the growth should neither lead to a decreasing level of quality nor to an increasing throughput time of orders. To show the dynamics of the growth of the department we built a model. This model helps our clients to take better decisions concerning inflow of new personnel and the amount of orders accepted over time. In the project we used the Participative Business Modelling approach. Participative Business Modelling (PBM) is a consulting approach which is a combination of business modelling from a System Dynamics point of view and from a process consulting perspective. In this paper we focus on aspects from the consulting process from a practitioners point of view. We will not describe the model in detail.
Software projects are of major importance. Technical aspects have advanced. But not software project management: this is now the key area in which improvement is urgently needed. It comprises the functions responsible to keep the project within cost, and duration targets: interfacing with the Client and sub-contractors, and managing the interactions between planning, monitoring, technical development, QA and configuration management. In this paper we focus on three main functions of project control: estimating, planning, and progress monitoring.
Major projects generally involve a client and a contractor. The client often essential for approving intermediate milestones or documentation, can however, cause detrimental effects to the project, requiring changes to work scope or the product definition, delaying documentation approval or essential information, requiring too much reporting, or tightening milestone schedules. If the relationship starts to deteriorate, positive dynamics can be set up, and many such are discussed in this paper. These effects must be analysed and quantified: to keep control of the project costs and time, to estimate correctly the true cost of contract amendments, and where necessary to make auditable claims against the client. Traditional project management tools are based around decomposing the project into constituent cost or time elements. These techniques have proven inadequate on their own for analysing and managing modern complex projects, which are increasingly becoming more complex and intra-related. A holistic approach must be used, particularly to deal with systemic effects such as multiple client actions. A natural technique for modelling such effects qualitatively is cognitive maps/ influence-diagram: a natural extension is to develop these into System Dynamics (SD) models, able to capture both hard auditable systemic effects, and the softer human effects that play an important part but are harder to quantify. Academic and practical work has continued to demonstrate the usefulness of SD in project management, particularly supporting dispute resolution.
The purpose of this paper is to show that a combination of System Dynamics (SD) and the Methodology of Network Thinking (MNT) developed at the University of St. Gallen can help overcoming some of the limitations of the both methodologies, and realizing substantial synergies between them. Insights from an application of this synthesizing methodology, which we call "Integrative Systems Modelling", to a case study, - The RITTS (Regional Innovation and Technology Transfer System)- project in Aachen (Germany) support our assumption that MNT and SD are highly complementary methodologies. The experience of this intervention shows that MNT is excellent for eliciting knowledge on complex issues from those who incorporate theoretical understanding and practical experience. It helps in surfacing issues, finding consensual domains and building a communication culture in a team. However, the modelling capabilities of MNT are limited. They do not include formal quantitative modelling of variables and their relationships. Also, the possibilities for simulation and validation are very limited. To overcome these limitations, SD modelling is the ideal complement. The concept of "Integrative Systems Modelling" is outlined and its main steps of application are illustrated by means of the Aachen RITTS case. Thereby, also the advantages, limitations and complementarities of the GAMMA and ITHINK software packages in model building become visible.
This paper develops a simple model of a manufacturing firm in which a successful productivity improvement program is implemented. The model is used to show how a successful improvement program can fail to significantly improve a firm's financial performance. It is argued that the potential rates of improvement in the firm's capabilities can differ substantially based on the intrinsic complexity of those processes. The spread of improvement skills and commitment to the effort is modeled as a diffusion process among employees in a given area. The allocation of resources to support that commitment is represented as a dynamic adjustment process. The formulation, with the assumption of locally rational decision rules, results in the differential rates of improvement in the capacity and demand generating areas of the firm. If excess capacity results, interactions with traditional accounting, pricing, and human resources policies can create unanticipated side effects that result in sub-standard performance of failure of the program. Policies for mitigating these problems are discussed and analyzed.
The Revised Minimum Standard Model (RMSM) of the World Bank is a model which focuses on the financial flows of the economy, and its best use is found in countries which require necessary adjustment towards balancing its national accounts. It is used frequently in repairing countries Country Assistance Strategies (CAS) which are approved by the Bank's Board of Executive Directors as the basis for Bank strategy for each individual country. RMSM was first constructed in the early 70's to provide a framework for assessing financial needs and domestic growth opportunities. Its extended version, RMSM-X, is used extensively by the World Bank Country Operations departments for making macroeconomic projections and analyzing macroeconomic policies for all developing countries.
The paper deals with an extension of the Polis modeling process that concerns war-vessel type dynamics. The study provides an opportunity for considerations on conceptual distance in SD models. We address the question with stating that a complex system cannot be simulated by an invariant model and that its change require adjustment in the conceptual distance which can also imply the treatment of discrete events. The models of Kuhnian theory suggested by the literature allow us a comparison for concluding that the POLIS approach could be of more interest in the simulation practice of complex systems.
This study examines the cognitive processes of strategic decision making in simulated dynamic environments. The experimental study using two different types f interactive decision making games found that high performers adopted more feedforward strategy and they pursued more model expansion than low performers did. These findings were confirmed in a supplementary study which manipulated to force the subjects to use feedforward strategy in there dynamic decision making. Results suggest that, in dynamic decision environment, the performance relies on the decision making strategy that manages adopt, i.e., feedforward strategy rather than feedback strategy. This study concludes by discussing its implications for theoretical development and strategic decision makers in complex dynamics environments.
Past policy studies to reduce rural poverty in the developing countries have focused much attention to the issue of increasing food production and expanding economic growth but little attention to the issue of constraints imposed by degradation of agricultural land resources and the effects of expanding urban economy on rural development. Only in recent years have we seen increasing attention to the relationship between rural poverty and environment. Inquiry is, however, often done by simplistic one way causal relationship which, although often illuminating, does not provide a comprehensive understanding of the different interacting processes that create rural poverty and land degradation. Many of the analyses of poverty-environment relationships view that poverty is the cause of environmental destruction. The common assumption takes the poor to be ignorant and short-sighted 'slash-and-burn' agriculturist, wrecking destruction on the environment. Others would consider population growth resulting from poverty to be reinforcing environmental destruction. In the process of destroying the environment, the poor people also became the victims of environmental degradation.
The purpose of this paper is to describe the methodological approach followed to validate a dynamic hypothesis of service delivery and explain its implications for service quality. For a full report on the application of the methodology and the substantial results obtained in the analysis see Oliva (1996)
Optimization has not been an important part of system dynamics thus far, and for several good reasons: Simulation models have been sufficient to point out greater potential for improvement than what policy makers have been willing o embrace. Hence presumably minor improvements of policies might have seemed of little value. Even simple simulation results have been difficult to communicate, indicating that the results of complicated optimization efforts would be even harder to convey. Optimization methods have not been able to capture the richness of real decision problems characterized by simultaneous appearance of dynamics, nonlinearities and uncertainties. Hence there has been uncertainty about the transferability of solutions from simple to complex environments.
Numerous renewable resources have been exploited beyond limits for sustainable economic development. At times over-exploitation has been observed even in cases where management regimes have been in place. Thus it seems pertinent to search for explanations beyond the theory of the commons. An experiment is performed where subjects set reindeer quotas in a district where lichen has been severely depleted by preceding overgrazing. All subjects err on the side of over-exploitation. Behaviour seems to be dominated by inappropriate, static mental and inefficient heuristics. Hence a subtle information problem is revealed.
A wellknown generic manufacturing strategy indicates "focused" orientation on strategic resources allocation decisions. This is true in the general sense that they have to make optimal decisions under resource constraints such as capital, human resources, time, etc., We can find an assumption underlying the orientation that there exist trade-off relationships between competitive measures like cost, quality, etc..(Skinner, 1978) Our research objectives are to seek for insight into the trade-off relationship. It is an unavoidable lot to every company? The analysis on the Japanese world class companies hints there is high degree of freedom for any company to make it more competitive free from the relationship. It is more important for actual companies to exploit such freedom than assuming the relationship as a lot. Our research objectives include modeling a hypothetical strengthening competitiveness process based on the results extracted from the positive analysis of the structure of competitive measures. Such task may give us implications to build up competitive companies.
Although system dynamics has long been applied to strategic business problems, there has been surprisingly little published work dealing with the topic of diversification and multibusiness firms. Widely cited business models in the field typically deal with dynamics at the level if a single business or else at the level of an industry strategic group. Nevertheless, diversified firms are numerous and have been studied closely by academics working in the area of corporate strategy. Much debate surrounds the question of whether (and under what circumstances) diversified firms can outperform firms that focus on a single core business. Researchers on this area have principally concerned themselves with statistical analyses of the link between financial performance and portfolio relatedness (Markides and Williamson 1994, Robins and Wiersema 1995)
This study compares the effects of several strategies for building Korean Information Infrastructure (KII). Korean Government plans to invest about 45 trillion won for the next fifteen years to build Korean Information Infrastructure (Table 1). Using system dynamics model of Korean Information Infrastructure, this paper compare market vs. government initiative strategies for building KII and explain the development pattern of KII under different strategies. Model building was proceeded in accordance with group model building procedure (Richardson & Andersen, 1995).
According to the research-based literature, essence of firm's idiosyncrasies is better investigated looking at the bundle of resources that constitutes them. According to this view, this paper examines the role of cumulated experience in influencing strategy-making process by directing selection of strategic initiatives. Moreover, this work regards it as necessary to look at the organisational and behaviuoral systems in which resources are embedded. For this reason, it places itself in the area of research, within the research-based view of the firm, recently denominated 'Competitive Organizational Behaviour' that studies the strategic consequences of behavioural and social phenomena within the firm jointly with the content of strategy and the competitive context [Barney and Zajac, 1992]. Taking this intraorganisational point of view, it is argued that firms not only cumulate experience that enhances their ability to simulation approach is used to explore the consequences of such assumption. A firm is represented that allocates funds among competing strategic initiatives using evolving routines. On one hand, the firm learns and exploits accumulated knowledge, on the other hand, it is strongly biased by past experiences. A behavioural perspective is therefore, taken in highlighting heuristics and biases in the strategy-making process. As a result, the paper (i) proposes some areas of analysis as crucial to address the paradox of taking advantage of core capabilities without being hampered by their dysfunctional flip side learning ( Leonard-Barton, 1992) (ii) investigates the suitability of system dynamics modelling to this kind of analysis.
Between 1994 and 1995 the Office of Regulatory and Management Assistance (ORMA) of New York State became interested in reengineering the processes whereby it interacted with the public. Specifically, the agency was having difficultly responding to phone inquiries for business permits automated voice response customer service system. ORMA approached the Center for Technology in Government (CTG), a research and development unit of New York State Government, requesting that such system be developed on a prototype basis and evacuated for feasibility.
The paper aims to describe an approach to identify suitable policies to deal with manufacturing workplace accidents, both their causes and effects. Particular emphasis has been put on the retention and application of safety knowledge by workforces, in conjunction with both reactive and proactive safety policies. The paper shows the possibility that safety in the workplace can lead to improved profits.
Successful corporate management requires specialization, i.e. the separation of tasks. In a historic perspective this lead to the manufacturing philosophy of "Taylorism" and the delegation of decision making- concepts that have proved highly successful in the past. But the same developments bear the risk of failure through uncoordinated activities. Management becomes futile without coherent action. Especially in a dynamic environment, as it is found e.g. in innovation management, this (potential) gap between isolated operations and coherent strategy has to be closed, Team or Cooperative Learning is necessary to define and to achieve the overall corporate objectives (Sengw 1990: Argyris 1990) Management games works as catalyst in such a process of group decision making. They counteract narrow specialization, lead to improved communication between different corporate functions, and encourage the identification and the pursuit of shared values and overall objectives.
Business Process Reengineering (BPR) is a methodology for fundamentally changing key business processes to improve performance. The type of systemic change implied by the notion in "radical rethinking of business processes" lends itself well to a systems dynamics (SD) approach, In this paper, we describe how various SD tools have helped our reengineering team implement fundamental changes to our material planning and control processes at Silicon Graphics (SGI). These methods have helped our organization gain a deeper understanding of our supply chain dynamics, develop alternative structures and ultimately change the way material flow is managed.
Maintenance is one of the major functions in production activities. It has a high direct cost and a profound impact on overhead cost through availability of equipment. Maintenance programs are either reactive or proactive. In reactive programs repairs are made when equipment fails. Proactive maintenance is a form of preventive or predictive maintenance. Preventive maintenance (PM) is the regularly scheduled process of performing certain types of maintenance, inspections, adjustments, and lubrications or equipment prior to failure. While it is being recognized that the higher production uptime and product yields more than justify the expense of their preventive maintenance programs, many plants experience frequent wanes in their preventive maintenance programs. Some plants have shown oscillatory behavior back and forth between preventive and reactive maintenance without much leaning about the cause.
The paper describes a dynamics model of fabricated metal manufacturing industry for Australian economy. Major subsectors considered in the model are: production, customer order, sales and capacity acquisition. The policy runs focus towards understanding of behaviour of capacity, inventory, production and costs.
The paper attempts to relate the operational elements of manufacturing organisations to the overall theme of quality. A common modelling framework is developed to bring together a number of issues such as technological flexibility, training and motivation, product improvement, process improvement, customer satisfaction, productivity and quality costs. The model is under validation and testing stage, and the policy options which will be evaluated are related to technological flexibility, investment, and employee development.
The domain of strategic decision making involves very complex issues with action-reaction relationships. In reality, there are system dynamics -based stimulation tools that help business managers understand t he fundamental processes of their businesses. In this research paper, we have studied the strategic market in the passenger airline industry for an international city pair between Perth and Singapore. Based on the study of major players on this route sector, we have attempted to model all the significant market elements and forces that demonstrate their explicit and implicit behaviours. The model developed in "iThink", a system dynamics-based stimulation software, provides an interactive capability to the business manager for the exploration of alternative scenarios so that the decision maker can understand how the pricing or competitive positioning activities of other players affect the market leader and vice-versa.
The spread of an innovation in the market is a highly dynamics process. Management science has developed a plenty of descriptive or normative methods, models and instruments to model this process. The research reaches back to 2960 with the models developed by Fourt/Woodlock, Mansfield and Bass (Fourt/Woodlock 1960; Mansfield 1961; Bass 1969). These models regard the diffusion of an innovation over time as a quasi natural process--like the spread a disease--neglecting variables that allow to control the speed of innovation diffusion through corporate decisions. However, these fundamental models have been the basis for a variety of developments in this particular field. However, only a few of them consider the variety of influencing elements of the innovation diffusion (for an overview on the different models see e.g., Manhajan/Peterson 1985; Mahajan/Muller/Bass 1990:Maier 1995a) They concentrate on one or a combination of some of the decision variables, e.g., some models have been developed to seek for the optimum pricing or advertising strategies. Some models are simple in structure, regarding only monopolistic markets and neglecting important management decision variables. Some models are little more complex, considering oligopolistic or dynamic market structures. However, management decision variables are mostly exogenous inputs into the model, no feedback between management decisions and the spread of a new product in the market, and the success of a product exists.
Companies are complex and dynamic systems that have to be managed: information about the actual state of the systems has to be analyzed, decisions have to be drawn and then transformed into actions. However, due to the complexity and the dynamics of the systems, company, management is a very difficult venture. Therefore, tools, theories and methods are needed to make management easier and more effective. In our system dynamics community of researchers, lectures and practitioners it is a fundamental and clear paradigm that system dynamics bases modeling and simulation can enhance the understanding of complex systems and because of that it can improve decision making.
This Graduate Level Course for k-12 Teachers will introduce them to the General Systems Theory method of Thinking. This thought process is different from the analytical Mechanistic Method of Thinking from the Renaissance Period which produced the Industrial Revolution. The use of General Systems Theory, System Thinking and System Dynamics is aimed at bringing cohesion, meaning and interdependence to the k-12 curriculum. This process can introduce thinking, curiosity, creativity, and real world meaningful learning experiences in the classroom. The k-12 education establishment in the U.S. which is criticized for not preparing the students properly for college and the workplace could make a giant step forward by using System Thinking across the curriculum in the classroom. This is an introductory course in System Thinking and the Philosophy of the Systems View of Reality. The history of the thought process of Systems thinking and its application in the past, the present and the future is explored. Comparison with the Mechanistic View of Reality is presented. In depth studies of open, closed and feedback systems are developed and applied to social science, ecology, economics, biology, health care, physics, chemistry, mathematics, literature, government, business and etc.. Some of the graphical and software tool which have been developed for the study of systems will be uses. About 50% of the course will involve working on the application of system thinking and the computer simulation of systems. A new text was written for this course. The following twelve overheads summarizes the material and structure of this course. The text will be in draft form by the middle of 1996.