A system dynamics model of individual performance is developed and simulated. Performance, a behavioral factor, depends upon and influences emotional and cognitive factors: stress, mood, and motivation. Activation, found in both stress and motivation literatures, is treated separately. Each causal relationship is assumed to be simple and unambiguous. Analysis of the model output under a range of work conditions shows that ambiguous or complex relationships would be supported by traditional research. Complex relationships between stress, motivation, and individual performance emerge from model structure and interactions, rather than from assumed causality. This work demonstrates the benefit of simulation in theorizing when multiple factors operate in tandem.
We model the dynamics associated with evolution of the core and the periphery of a social-network. The model is based on an existing behavioral theory of the inter-firm (Baum and Ingram 2002). The formalization allows us to refine this existing theory through the introduction of a target setting process. Allied analysis documents the efficacy of exploration and exploitation policies within the core and across the periphery of a social network. Our results show that the competitive advantage accrued through exploration and exploitation is crucially affected by the behavioral biases, imitation and the target setting associated with the evolution of key constructs.
This paper, through two separate teaching fragments in the delivery of chemistry education, is to demonstrate the use of system dynamics and the subsequent research process by using software STELLA, which clearly reflects the system thinking.
As to the decomposing reaction of H2O2, students encountered some unexpected reaction phenomenon. With the help of the STELLA, they conducted in-depth research on the causes that lead to such phenomenon mentioned above. The final modeling process clarifies the reaction for the students. Whats more important, it also helps them form the initial concept of system thinking.
When studying molar volume of gas, the teacher took as the starting point the four famous Chinese ancient inventions and then moved further to the study of rocket propeller. From the viewpoint of a student at secondary school, they gradually uncover the underpinning theories of rocket propeller. This process brought to them a great sense of achievement and joy.
Such a process is beyond any imagination in our traditional teaching conduct. It is not only a harmonious combination of system thinking and the studying of chemistry theories, but in addition, it brings the fundamental reforms in the chemistry education at secondary schools.
What aspects of basic system dynamics are covered by the traditional school math curriculum? The Booth Sweeney and Sterman (2000) bathtub tasks and the Jensen and Brehmer (2003) rabbits-and-foxes task were dissected into aspects. Questionnaires with tasks tapping into the identified aspects were administered to first-semester university students with a math-intensive high school background. Performance were as expected and conformed to the results of previous studies with these tasks. These results encourage further effort to devise additional tasks covering more basic aspects identified, and refining the existing tasks. Equipped with a well-design battery of tasks, it would in all likelihood be informative to test it with different participant groups, such as undergraduate, as well as graduate, students in math, engineering, and system dynamics.
Housing for the poor remains a major policy problem in U.S. cities. Jay Forresters 1969 Urban Model predicted that increasing the availability of low income housing exacerbates the city deterioration. Poverty and homelessness are on the rise in this country. Families, often single parents with children, and the elderly are two of the largest groups affected. Subsidized housing is one way to fight homelessness. This years budget proposal has President Bush slashing funding to the department of Housing and Urban Development, including many programs that help supply housing to the poor. I plan to investigate various low income housing policies to determine how and why they would or would not work.
As New Year rolls in, many of us take on challenge of personal change. Many set goals to lose weight; do more exercises; watch less television; do more studying; do less partying; or to shed a habit such as smoking. For several years in our Quality Management course students were asked to work on a term-long personal continuous improvement projects. The students were briefly introduced to basic concepts of causal loop diagrams and were encouraged to use them to clarify their theories regarding their own progress or lack of it. The basic premise is that the result students obtain and the dynamics they experience are built into the structure of their worldview and they learn if they can communicate and influence their worldview. This paper uses systems thinking lens to discuss the improvement framework and the experience reported by students. Majority of students did not make the progress toward their goals as much as they would have preferred. The student generated diagrams to explain their theories were either too simple or overly complicated, awkward and partially flawed. However, it can be claimed that the process of using the tool to clarify their thinking itself was worthwhile. After reviewing their narratives and the diagrams, several archetypes were consistently noted.
The Advanced Fuel Cycle Initiative is developing a system dynamics model as part of their broad systems analysis of future nuclear energy in the United States. The model will be used to analyze and compare various proposed technology deployment scenarios. The model will also give a better understanding of the linkages between the various components of the nuclear fuel cycle that includes uranium resources, reactor number and mix, nuclear fuel type and waste management. Each of these components is tightly connected to the nuclear fuel cycle but usually analyzed in isolation of the other parts. This model will attempt to bridge these components into a single model for analysis. This work is part of a multi-national laboratory effort between Argonne National Laboratory, Idaho National Laboratory and United States Department of Energy. This paper summarizes the basics of the system dynamics model and looks at some results from the model.
Past performance may not be a not true indicator of future performance. Everyone has seen this disclaimer at one time or another. Although this may certainly be true, past performance should certainly be considered when planning for the future. Executives are always seeking ways to make decisions that will help their company to perform better. This paper examines a model that was developed to take a companys financial records and transform them into easy to understand trends and long-term predictors. In addition, it allows the user to adjust system parameters to see the long-term effects to performance.
This study applies system dynamics to explore the long-term influences of multiple policies on handling the financial imbalance of the National Health Insurance (NHI). In order to improve the financial imbalance of the NHI, three policies and three scenarios are proposed. Each policy is evaluated for each scenario. According to the simulation results, the policy of a 20% increase in premium rate, plus a 2% decrease each year in annual rate of change of benefit payments per beneficiary can improve the financial imbalance. However, the benefit payments will be greater than premium revenues from 2008. So, the financial imbalance of the NHI will present again.
The National Health Insurance (NHI) program has implemented in Taiwan since March 1995. The initial balance of revenues and expenditures was stable, but there has been a deficit since 1998. As the deficit problem was mostly caused by the payment system of fee-for-service, the Bureau of NHI (BNHI) implemented global budget (GB) payment system. Under GB, the benefit payments were under control as planned. Since the benefit payments from BNHI are the most part of revenues of hospitals, some hospitals have financial imbalance.
This study uses system dynamics to explore the strategies of hospitals facing GB and evaluate its effects on hospitals and patients. This research is still ongoing and will reach two achievements. First, submitting the stock-flow diagrams can provide the managers of hospitals to have a further understanding on their strategies. Second, building the model can simulate and evaluate the effects of multiple strategies on hospitals and patients.