The construction industry in Uganda is characterized by a high incidence rate of accidents. During the late 1990s, an annual average of 49 accidents were reported in the construction industry while during the period 2001 to 2005, the annual average for this sector was 103 cases. Between 2006 and 2010, more construction accidents were registered with a total of 49 fatalities reported in Kampala metropolitan area alone. This trend has continued up to the present date. Meanwhile, the demand for housing in Uganda exceeds supply resulting into a huge housing deficit. Rapid population growth without matching housing facilities has been cited as the main cause of the housing deficit. Land holding in Uganda is characterized by multiple rights of ownership, and high social costs including land conflicts and violent evictions. Reportedly, these developments are affecting the performance of the housing sector. Given the above background, the aim of this thesis is to propose policies and strategies for improvement of construction safety performance and the housing sector in Uganda. The thesis is based on two broad themes i.e. construction safety performance and housing markets. Although the research themes are unique in their own right, they both address pertinent issues concerning the construction industry in Uganda. Whereas the first theme investigates accidents as events that affect the production of construction infrastructure (including housing), the second theme handles topical issues which affect the demand and supply for housing in Uganda. The study area is Kampala, the capital city of Uganda. In addition to the overview chapter, this thesis contains four research papers. The first two papers relate to theme on construction safety performance whereas the last two papers relate to theme on housing markets. The first paper investigates the causes of construction accidents in Kampala, establishes the prevailing injury and fatality rates, examines spatial patterns in occurrence of accidents and thereafter, proposes strategies of mitigating accidents. The second paper investigates how undiscovered rework (defined as unnecessary effort of redoing a process or activity that is incorrectly implemented the first time) leads to accidents, develops a computer based model for simulating occurrence of accidents on projects and thereafter, proposes strategies of reducing rework related accidents. Evidently, the first paper is explorative investigating construction safety issues at industry level, whereas the second paper is more specific studying safety dynamics at project level. The third paper investigates how the choice of land tenure system affects housing values and thereafter, proposes strategies of mitigating the negative effects of land tenure on the housing market. Finally, the fourth paper examines how population changes affect the housing needs of a city, develops a computer based model for simulating the city population and housing needs, and experiments a plethora of housing policy proposals. Overall, findings of this thesis such as the concept of spatial dependence in occurrence of construction accidents, where accidents at one location were found to be associated with those which occur in the neighborhood; the phenomenon of congestion, defined in this thesis as the existence of high building density amidst many fulltime workers on site, and its significant association with accidents occurrence; and the uniqueness of private mailo land tenure system and the 12% premium it offers in housing values amidst high social costs, are unique contributions to the existing body of knowledge. / <p>ISBN: 978-91-87111-05-01</p><p>QC 20150522</p> / None

Nos últimos anos, a simulação computacional vem assumindo uma importância cada vez maior como ferramenta de aquisição de conhecimento. Na simulação desenvolvida nos primórdios da Pesquisa Operacional, os problemas eram resolvidos por meio da obtenção dos melhores resultados possíveis para cada parte individual do modelo. Entretanto, à medida que a complexidade dos problemas cresceu, surgiu a necessidade de se utilizar uma abordagem mais sistêmica e generalista. A simulação utilizou-se, inicialmente, de linguagens de programação geral, como o FORTRAN. Mas, à medida que a complexidade das observações e a capacidade dos recursos computacionais cresceram, surgiram os programas de simulação de propósito geral (como o GPSS) e os baseados na Dinâmica dos Sistemas (DYNAMO, STELLA etc). Essa metodologia (dinâmica dos sistemas) faz uso do conceito de pensamento sistêmico para a resolução de problemas e para o estudo de sistemas. Nesse contexto, o presente trabalho tem como principal objetivo identificar e analisar os aspectos potenciais da simulação enquanto ferramenta de aquisição de conhecimento. Para atingir esse objetivo, aplica-se a simulação a um sistema de fila de uma fábrica de componentes plásticos. / In the last years, the computer simulation has become a vital tool in the development of several self-learning techniques, as well in the acquisition of knowledge in the engineering teaching and in the managerial training. The simulation used in the early years of the Operational Research boarded the potential problems by obtaining the best possible results for each part of the model. However, as the complexity of such problems increased, the need for more systemic and generalist approaches has also increased. Initially, the simulation was performed by general programming languages as FORTRAN. But, as the complexity of the observations and the capability of the computer resources increased, Simulation Languages (like GPSS) and Dynamic System Simulation Software (dynamo, STELLA etc) were developed. This methodology (“System Dynamics") uses concepts of the systemic thought to solve problems and to analyze systems. In that context, the main objectives of this work are to identify and to analyze the potential aspects of the simulation based on System Dynamics when applied in the engineering teaching and in the managerial training.

As the economy has been growing fast in China, Chinese people have more incomes and then higher standard of living. In the case of household water treatment, more and more urban residents in China use bottled water or water filtration system instead of tap water because people start to worry about polluted tap water. According to a survey from China Water Supply Services Promotion Alliance in 2014, 59% of urban residents drinking water is from tap water (after being boiled), 41% from bottled water and water filtration system. The 41% participants prefer bottled water as the first choice over a water filtration system. The comparative advantages and disadvantages of home water filtration system and bottled water are analyzed using comparative analysis. The reasons why home water filtration industry has grown slowly in urban China even though it is less expensive and has environmental benefits are analyzed using a system dynamics model. The model focuses on the physical system of home water filtration industry. The study shows that order delivery delay and service time are key factors to the adoption rate of home water filtration system. However, initial cost becomes a limiting factor to the growth of the market of home water filtration system. The study proposes the according market policy, demand policy, and supply policy to improve the current scenario.

"Development on the basis of extraction and export of natural resources is a dynamically complex problem. Empirical evidence shows that while some nations have been successful to translate natural resource wealth into long-term development but many have failed too. In this dissertation a system dynamics approach is taken to understand why this is happening and what strategies could facilitate a resource-based development process. In this regard, Mashayekhi’s model of oil-dependency of Iranian economy as one of the few relevant system dynamics examples is updated and revalidated. The results show that despite its capability in showing the dynamics of the problem from an economic perspective it lacks socio-political features that are necessary to address the most fundamental issues of resource-based development. It is shown that Katouzian’s theory of “arbitrary state and society” could fill this gap. The theory is, thus, translated into a system dynamics model so that it could be tested for internal consistency and used for policy analysis. The model is able to explain long-term socio-political-economic instability of a resource-dependent society. On the basis of Mashayekhi’s model, Katouzian’s theory, and other fundamental explanations of natural resource dependency that are available from the literature, a generic eclectic model is developed. The model has gone through a comprehensive list of confidence-building tests. Controlled experimentation through Monte Carlo simulations show that, on the contrary to the current belief, it is unlikely that natural resource wealth be harmful for social welfare. Results also revealed that rule of law is a crucial factor that affects trajectory of the socio-political-economic development. Other findings are as follow. Civil resistance (disobedience) can be harmful for the system in the long-run. While sanctions could affect the economy it has barely an impact on socio-political settings of a society. Finally, wage stabilization, facilitation of social mobility, and privatization of natural resource revenues within certain limits) could help the resource-based development to achieve better outcomes."

Hospitals are looking to industry for proven tools to manage increasingly complex operations and reduce costs simultaneously with improving quality of care. Currently, €˜lean€™ is the preferred system redesign paradigm, which focuses on removing process waste and variation. However, the high level of complexity and uncertainty inherent to healthcare make it incredibly challenging to remove variability and achieve the stable process rates necessary for lean redesign efforts to be effective. This research explores the use of an alternative redesign paradigm €“ €˜agile€™ €“ which was developed in manufacturing to optimize product delivery in volatile demand environments with highly variable customer requirements. €˜Agile€™ redesign focuses on increasing system responsiveness to customers through improved resource coordination and flexibility. System dynamics simulation and empirical case study are used to explore the impact of following an agile redesign approach in healthcare on service access, care quality, and cost; determine the comparative effectiveness of individual agile redesign strategies; and identify opportunities where lean methods can contribute to the creation of responsive, agile enterprises by analyzing hybrid lean-agile approaches. This dissertation contributes to the emerging literature on applying supply chain management concepts in healthcare, and opens a new path for designing healthcare systems that provide the right care, at the right time, to the right patient, at the lowest price.

"Development on the basis of extraction and export of natural resources is a dynamically complex problem. Empirical evidence shows that while some nations have been successful to translate natural resource wealth into long-term development but many have failed too. In this dissertation a system dynamics approach is taken to understand why this is happening and what strategies could facilitate a resource-based development process. In this regard, Mashayekhi’s model of oil-dependency of Iranian economy as one of the few relevant system dynamics examples is updated and revalidated. The results show that despite its capability in showing the dynamics of the problem from an economic perspective it lacks socio-political features that are necessary to address the most fundamental issues of resource-based development. It is shown that Katouzian’s theory of “arbitrary state and society” could fill this gap. The theory is, thus, translated into a system dynamics model so that it could be tested for internal consistency and used for policy analysis. The model is able to explain long-term socio-political-economic instability of a resource-dependent society. On the basis of Mashayekhi’s model, Katouzian’s theory, and other fundamental explanations of natural resource dependency that are available from the literature, a generic eclectic model is developed. The model has gone through a comprehensive list of confidence-building tests. Controlled experimentation through Monte Carlo simulations show that, on the contrary to the current belief, it is unlikely that natural resource wealth be harmful for social welfare. Results also revealed that rule of law is a crucial factor that affects trajectory of the socio-political-economic development. Other findings are as follow. Civil resistance (disobedience) can be harmful for the system in the long-run. While sanctions could affect the economy it has barely an impact on socio-political settings of a society. Finally, wage stabilization, facilitation of social mobility, and privatization of natural resource revenues within certain limits) could help the resource-based development to achieve better outcomes."

The Excellent Enterprise's successful secret is always an important subject discussed by the enterprise operators and the managerial educational field.The scholars used to mention that the ¡§Intangible Resources " have great influence to the organization, and suggest that the characteristic of successful enterprise should contain soft variable such as culture, leadership and so on. Among them, some of the text books and publication of entrepreneur emphasized that the mission is one of the key factors for organizational management.In the past research of how mission influences organization effectiveness, researcher used interview and statistical analysis as major research methods, however, if we use System Dynamics as another approach of research method to establish the enterprise model could present the process of how mission Influence organization effectiveness more specifically. The merit of System Dynamics Model is that all of organizational issue of the management process is dynamical complexity, non-linearity, however, System Dynamics Model simulation process may help the modeler understand the relationship between system structure and behavior, and the static system feedback diagrams will become dynamical ¡§future laboratory". However, because of the soft variable lacking for specific index and method for measurement, it is still a challenge to put the soft variables in the Enterprise Model. This paper adopt System Dynamic as the research method to study how loyalty for mission of a leader in excellence enterprise influence organizational performance ¡V taking Japanese Matsushita Electricity industrial Ltd. Company as the case company to analyze how the mission loyalty affect the soft variables of organization and produce the indirect influence to the organization. By collecting researches of Excellence Enterprise and information of Matsushita Electric Ltd. Company, we constructed the Matsushita Electric Ltd. Company¡¦s System Dynamics Model, and put the soft variables in to model and run the simulation, find out the relationship between Excellence Mission and organizational performance. By discussing how the leader¡¦s Mission loyalty affects the organizational performance indirectly, we can prove that soft variables in organizational business and the System Dynamics modeling cannot be neglected.

The genus Chlamydiae encompasses a unique class of obligate intracellular bacteria that can cause disease in a wide range of animals. In humans, Chlamydia trachomatis infections are common and are frequently observed in diseases of the eye, genital and respiratory tracts. Prevalent worldwide, Chlamydia infections can progress to chronic inflammatory sequellae and are the leading cause of curable sexually transmitted disease and preventable blindness. After falling in the face of intensified control efforts, case notifications of sexually transmitted Chlamydia in many countries are rising. In many jurisdictions, this unprecedented rise of Chlamydia case notifications has occurred after the introduction of wide spread control programs, and has been discussed to be a result of either increased testing volume, improvements to testing technologies, changes in sexual behaviour, or increased reinfection rates brought about by deleterious effects of treatment on acquired immunity. This thesis seeks to answer the question of why observed Chlamydia case notifications have rebounded? I have attempted to answer this question using simple dynamical models of Chlamydia transmission framed from immunological and epidemiological perspectives. Model structures are drawn from frameworks previously used for studying sexually transmitted infections, and represent a combination of theoretical and data-oriented formulations, as well as different (hierarchical) ecological scales. The results of this thesis highlight that increased testing volumes, rather than changes in the sensitivity and specificity of testing technologies, sexual behaviour, or truncated immunological responses brought about by treatment can explain the increase in observed chlamydia case notifications, and that simple explanations for these observed rates appear to have been dismissed in favor of an increase to the underlying prevalence. In addition to providing insights into current epidemiological trends, this thesis has also been able to produce significant insights into the natural history of chlamydial infection. In particular, the phenotype of an individual's immunobiology that results from multiple chlamydial infections suggests that longer periods between initial and repeat infection may increase an individual's chlamydial load, their duration of infection, as well as non-intuitively the formation of protective immunity, persistent infection, and the potential for immunopathogenesis. Additional population-scale analyses in this thesis also suggest the existence of a period of immunity that is, on average, much longer lasting than currently discussed in contemporary literature. The results of this research outline a potential way forward through filling several gaps in the immunological and epidemiological understanding of Chlamydia infections that involves both reviewing existing data as well as continued research using "systems science" approaches.

Agile software development challenges the traditional way of software development and project management. In rapidly changing environments, changing requirements and tight schedule constraints require software developers to take a different approach toward the process of software development. However, beyond a few case studies, surveys and studies focused on specific practices such as pair programming, the effectiveness and applicability of agile methods have not been established adequately. The objective of my research is to improve the understanding of and gain insights into these issues. For this purpose, I develop a system dynamic simulation model that considers the complex interdependencies among the variety of practices used in agile development. The model is developed on the basis of an extensive review of the literature as well as quantitative and qualitative data collected from real projects in seven organizations. The development of the model was guided by dynamic hypotheses on customer involvement, refactoring and quality of design. The model was refined and validated using data from independent projects. The model helps in answering important questions on the impact of customer behavior, cost of making changes and economics of pair programming. Experimentation with the model suggests that the cost of change is not constant; instead, its value changes cyclically and increases towards the later phase of development. Also, the results of simulation show that with no pair programming, fewer tasks are delivered and it costs more to deliver a task when compared to development with pair programming. Further, customer behavior has a major impact on project performance. The quality of customer feedback is found to be very critical to the successful of an agile software development project. The primary contribution of this research is the simulation model of agile software development that can be used a tool to examine the impact of agile practices and management policies on critical project variables including project scope, schedule, and cost. This research provides a mechanism to study agile development as a dynamic system of practices rather than using a static view and in isolation. The results from this study are expected to be of significant interest to practitioners of agile methods by providing them a simulation environment to examine the impact of their practices, procedures and management policies.

The genus Chlamydiae encompasses a unique class of obligate intracellular bacteria that can cause disease in a wide range of animals. In humans, Chlamydia trachomatis infections are common and are frequently observed in diseases of the eye, genital and respiratory tracts. Prevalent worldwide, Chlamydia infections can progress to chronic inflammatory sequellae and are the leading cause of curable sexually transmitted disease and preventable blindness. After falling in the face of intensified control efforts, case notifications of sexually transmitted Chlamydia in many countries are rising. In many jurisdictions, this unprecedented rise of Chlamydia case notifications has occurred after the introduction of wide spread control programs, and has been discussed to be a result of either increased testing volume, improvements to testing technologies, changes in sexual behaviour, or increased reinfection rates brought about by deleterious effects of treatment on acquired immunity. This thesis seeks to answer the question of why observed Chlamydia case notifications have rebounded? I have attempted to answer this question using simple dynamical models of Chlamydia transmission framed from immunological and epidemiological perspectives. Model structures are drawn from frameworks previously used for studying sexually transmitted infections, and represent a combination of theoretical and data-oriented formulations, as well as different (hierarchical) ecological scales. The results of this thesis highlight that increased testing volumes, rather than changes in the sensitivity and specificity of testing technologies, sexual behaviour, or truncated immunological responses brought about by treatment can explain the increase in observed chlamydia case notifications, and that simple explanations for these observed rates appear to have been dismissed in favor of an increase to the underlying prevalence. In addition to providing insights into current epidemiological trends, this thesis has also been able to produce significant insights into the natural history of chlamydial infection. In particular, the phenotype of an individual's immunobiology that results from multiple chlamydial infections suggests that longer periods between initial and repeat infection may increase an individual's chlamydial load, their duration of infection, as well as non-intuitively the formation of protective immunity, persistent infection, and the potential for immunopathogenesis. Additional population-scale analyses in this thesis also suggest the existence of a period of immunity that is, on average, much longer lasting than currently discussed in contemporary literature. The results of this research outline a potential way forward through filling several gaps in the immunological and epidemiological understanding of Chlamydia infections that involves both reviewing existing data as well as continued research using "systems science" approaches.