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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
41

Simulating Government Institutions in Networked Societies

Richards, Michael 18 December 2023 (has links) (PDF)
Modern human societies give rise to the expression of complex group dynamics between the members of said society due to the abundance of continued interactions. Of particular interest are how institutions affect these interactions between societal members, alter the resulting group dynamics, and impact society as a whole through their rules. Simulating these dynamics allows for greater insight into how these institutions function and allows researchers to pose interesting questions and test hypotheses within a laboratory setting. We present a novel approach to simulating institutions, particularly governments, within a networked society. This approach builds upon the Junior High Game, which models a society of mixed motive individuals that are subject to reputation, network and power dynamics. In this work, we take a step towards evaluating the Junior High Game's ability to simulate societies with government institutions through evolutionary simulation. We evaluate the results through the simulated society's total welfare, equality, and group dynamics.
42

A DECISION SUPPORT SYSTEM FOR MANUFACTURED HOUSING PRODUCTION PROCESS PLANNING AND FACILITY LAYOUT

ABU HAMAD, AYMAN ABDALLAH January 2003 (has links)
No description available.
43

Predictive Simulation of Rowing Exercise

Zarei, Milad, Zarei 31 August 2016 (has links)
No description available.
44

Assessing Wireless Network Dependability Using Neural Networks

Rastogi, Preeti January 2005 (has links)
No description available.
45

TESTING CRIMINOLOGICAL AND SOCIOLOGICAL EXPLANATIONS FOR THE FORMATION OF HATE GROUPS

Breen, Clairissa D. January 2011 (has links)
The purpose of this dissertation is to employ simulation modeling to test theories of group formation as they pertain to hate groups: groups whose hate ideology may or may not condone violent criminal behavior. As of 2010, there were 1002 hate groups known to be active in the United States. Previous examinations of hate groups have assumed formation. This dissertation uses simulation modeling to test Hamm's (2004) criminological theory of collective hate and Weber's (1947) socio-political theory of charismatic leadership. Simulation modeling is designed to create a computer simulation that simplifies people and their interactions to mimic a real world event or phenomena. Three different experiments were tested using five models of hate group formation. These experiments test the importance of personal and societal levels of hate in group formation and the influence of charismatic leadership. These experiments also tested hypotheses regarding the number of groups that form, the speed of formation and group size. Data to test these hypotheses was collected from fifteen thousand model iterations. All three models successfully generated hate groups. Hate groups were generated at all levels of societal hate. An in-depth understanding of how hate groups form may assist in slowing the proliferation of these groups and decreasing their appeal. / Criminal Justice
46

Street Robbery Patterns: A Mixed Method Test of Situational Action Theory and Crime Pattern Theory

Eidson, Jillian L January 2020 (has links)
According to current scholarship on offender decision making, choosing to rob another is based on a variety of individual and situational characteristics. Explanatory models often invoked within environmental criminology include routine activity, rational choice and crime pattern theories. Situational action theory’s suggestion that this decision depends, at least in part, on the interaction between offender criminal propensity and the setting’s moral context has yet to be examined. This investigation tests this idea by conducting structured interviews with active probationers and parolees centered on their decoding of streetscapes to clarify offenders’ perceptions of street robbery opportunities (Part I). These results inform an agent-based simulation contrasting the merits of assumptions made in the previously stated theories to learn how well each generates realistic concentrations of street robbery (Part II). Support emerges for both environmental criminology and situational action theory, but the results differed by the method employed. Implications follow for clarifying the theoretical processes driving these incidents and for promoting public safety. / Criminal Justice
47

Estimating the Impacts of SORNA in Pennsylvania: The Potential Consequences of Including Juveniles

Henderson, Jaime S. January 2015 (has links)
The federal Sex Offender Registration and Notification Act (SORNA; 2006) established a uniform, offense-based registration system for sex offenders age 14 and older. The legislation created a hierarchical, three-tier classification scheme in which convictions of the most severe sex offenses result in Tier III assignment and convictions of the least severe offenses yield Tier I delegation. Juveniles are treated the same as adults when adjudicated of serious, Tier III offenses such as rape and aggravated indecent assault. Tier III assignment requires lifetime registration and notification for offenders in jurisdictions in which they live, work, and go to school. On December 20th, 2011, Governor Corbett signed Pennsylvania's version of SORNA and it was implemented exactly one year later on December 20th, 2012. The project, which focuses on Pennsylvania's version of SORNA, comes at a time when the impact of this new law has yet to be assessed. This study explores the system resources necessary for implementing this legislation, including personnel, costs, and enhancements to technologies necessary for creating and disseminating information on sex offenders. Although it has garnered much attention because it places unfunded mandates on states, opposition on behalf of jurisdictions is largely due to the inclusion of juveniles. Many researchers and legal advocates have argued against the policy due to the amenability of juveniles to treatment, low recidivism rates among sex offenders, and the negative consequences lifetime registration may have on youthful offenders. In fact, no previous research supports registration and notification as effective tools for deterring sex offending. While the aforementioned concerns brought to the attention of the government are credible, they have been unsuccessful in producing change at the federal level. These concerns were influential in drafting Pennsylvania's legislation that limited the number of offenses that triggered registration and withheld juvenile information from the public website. This dissertation employed a mixed-methods design to investigate SORNA's potential effects based upon the inclusion of juveniles. Research questions focused on the workload of agencies who work with sex offenders, the potential costs associated with SORNA requirements, the number of juvenile offenders now and in the future who may be implicated by the legislation, and the opinions and experiences of practitioners who work with juvenile sex offenders. Data collected by the Pennsylvania Juvenile Court Judges' Commission were analyzed to investigate the research questions. Descriptive and bivariate inferential statistical analyses were conducted, in addition to data-validated dynamic systems modeling to provide a prospective analysis into how many youth may face lifetime registration across the Commonwealth. Costs incurred as a result of SORNA's requirements were explored as well. Following the quantitative analyses, interviews with practitioners were conducted to obtain opinions and insight on the projected volume of juvenile offenders affected by SORNA and fiscal information relevant to juvenile sex offender supervision, management, and registration. / Criminal Justice
48

Investigating the Impact of Urban Tree Planting Strategies for Shade and Residential Energy Conservation

Hwang, Won Hoi 04 September 2015 (has links)
Expanding urbanization, characterized by increased impervious surfaces and decreased tree canopy, is contributing to rising urban temperatures. This trend has implications for energy consumption, which strategically placed trees can modify by casting shade upon building and ground surfaces. However, urban densification, a paradigm of modern residential land development, often constrains space for planting shade trees. Thus, the overall objective of this dissertation was to investigate shade tree planting strategies and their effects on residential cooling and heating energy conservation for dense urban neighborhoods in U.S. cities on a latitudinal gradient. The first study used a computer program called Shadow Pattern Simulator to examine the effects of tree form, tree placement, and sunlight exposure on shade provision for a residential structure model. Simulation results affirmed the conventional strategy in northern latitudes that recommends planting shade trees on the east or west aspect for maximizing beneficial shade while avoiding tree plantings on the south aspect to minimize any heating penalty of undesirable shade. However, in southern latitudes, planting trees on southerly aspect should not be discounted because the shorter heating season lessens the detrimental heating penalty while providing beneficial season shade. The second study, using an energy simulation program called EnergyPlus, evaluated the effect of a single shade tree upon the energy consumption of the structure model. This study affirmed that energy conservation benefits are influenced by the quantity as well as the quality of tree shade upon building surfaces. In addition, interactions between sun angle, tree form, and tree placement were observed to influence tree shade effects on annual energy consumption. In the third study, based on the first two studies, an alternative tree placement strategy, which reconfigured tree placement around the residential structure, was developed to maximize cooling and heating energy savings while attenuating space conflicts. The alternative strategy was found to be as effective as the conventional strategy while being more responsive to parcel or building orientations in dense urban neighborhoods. Overall, understanding the fundamental interactions between tree form, tree placement, and geographic settings is critical for improving energy conservation benefits of shade trees in dense urban settings. / Ph. D.
49

Quantificação e modelagem de mecanismos de danos causados por Phakopsora euvitis e Plasmopara viticola em videira Vitis labrusca / Quantification and modelling of damage mechanisms caused by Phakopsora euvitis and Plasmopara viticola in Vitis labrusca

Nogueira Júnior, Antonio Fernandes 02 February 2017 (has links)
A viticultura no Brasil e no Estado de São Paulo encontra-se em expansão nos últimos 10 anos e a cv. Niagara Rosada (Vitis labrusca) se destaca como principal cultivar para produção de uvas para mesa. Essa cultivar é suscetível à várias doenças foliares, como a ferrugem (Phakopsora euvitis) e o míldio (Plasmopara viticola). Não existem estimativas quantitativas dos danos causados por essas doenças na cv. Niagara Rosada. Diante do exposto os objetivos desse trabalho foram quantificar os efeitos da ferrugem e do míldio nas trocas gasosas, nas limitações da fotossíntese, no acúmulo de biomassa, no acúmulo de carboidratos, e na produção da cv. Niagara Rosada e desenvolver um modelo de simulação para V. labrusca acoplado com os mecanismos de danos da ferrugem e míldio. Experimentos foram conduzidos, separadamente para cada doença, em condições controladas, em mudas inoculadas com diferentes concentrações de P. euvitis e P. viticola e em campo experimental. Medidas de trocas gasosas e curvas de resposta da taxa líquida de assimilação de CO2 ao aumento da concentração intercelular de CO2 (Ci) foram realizadas em mudas sadias e infectadas com P. euvitis e P. viticola. Teores de açúcares solúveis totais, sacarose e amido foram determinados em plantas sadias e inoculadas com os patógenos. P. euvitis e P. viticola reduziram a taxa fotossintética em plantas infectadas tanto na área da lesão como no tecido verde adjacente a lesão (lesão virtual). Valores do parâmetro β, indicativo da lesão virtual, foram de 5,7 e 2,9, respectivamente para P. euvitis e P. viticola. P. euvitis reduziu em 48%, 36% e 67% a atividade da Rubisco (Vcmax), a taxa máxima de transporte de elétrons usados para a regeneraração da RuBP (Jmax) e a condutância do mesofilo (gm), respectivamente, em folhas infectadas. A área foliar e biomassa de raízes em mudas inoculadas com P. euvitis foram reduzidas. Através de análises histopatológicas e da quantificação de amido nas folhas sadias e doentes foi possível observar o acúmulo de amido em regiões adjacentes às pústulas de P. euvitis. Mesmo em baixas severidades da ferrugem já se observam reduções no acúmulo de carboidratos em raízes. P. viticola reduziu Vcmax em 23,5 % em folhas infectadas comparadas às folhas sadias. P. viticola reduziu a biomassa de raízes e quantidade de carboidratos nas raízes de mudas doentes e de plantas no campo em ano de alta severidade da doença. Plantas no campo com sintomas míldio produziram em média 0,5 kg a menos do que plantas sadias e a principal causa da redução na produção foi a queda de bagas causada pela infecção de P. viticola nos cachos. Um modelo de simulação para Vitis labrusca foi desenvolvido, utilizando o software Stella®. A produção, partição e dinâmica da biomassa da videira foi simulada ao longo de 20 anos e os efeitos de P. euvitis e P. viticola na redução do tecido verde sadio da planta, na redução da eficiência fotossintética, no desvio de assimilados, na aceleração da senescência foliar e na queda de frutos foram inseridos no modelo. / Viticulture in Brazil and in the state of São Paulo has increased in the last 10 years and cv. Niagara Rosada (Vitis labrusca) is the main cultivar for the production of table grapes. This cultivar is susceptible to several foliar diseases, such as rust (Phakopsora euvitis) and downy mildew (Plasmopara viticola). There are no quantitative estimates of the damage caused by these pathogens in cv. Niagara Rosada. The objectives of this work were to quantify the effects of rust and downy mildew on gas exchange, photosynthesis limitations, biomass accumulation, carbohydrate accumulation and production of cv. Niagara Rosada and to develop a simulation model for V. labrusca coupled with damage mechanisms caused by rust and mildew. Experiments were conducted, independently for each disease, under controlled conditions in potted plants inoculated with different concentrations of P. euvitis and P. viticola and in experimental field, with natural occurrence of diseases. Measurements of gas exchange and response curves of photosynthetic rate to the increase of the intercellular CO2 concentration (Ci) were carried out in healthy plants and infected plants with P. euvitis and P. viticola. Total soluble sugars, sucrose and starch contents were determined in healthy plants and inoculated plants with the pathogens and kept under controlled conditions. P. euvitis and P. viticola reduced the photosynthetic rate in infected plants both in the area of the lesion and in the green tissue adjacent to the lesion (virtual lesion). Values of parameter β, indicative of the virtual lesion, were 5.8 and 2.9, respectively for P. euvitis and P. viticola. P. euvitis reduced the activity of Rubisco (Vcmax), rate of electrons transport contributing for the RuBP-regeneration (Jmax) and the conductance of mesophyll (gm), respectively, on infected leaves by 48%, 36% and 67%. The severity of P. euvitis reduced leaf area and biomass of plant roots. The histopathological analysis and starch quantification in the leaves allowed to observe starch accumulation in regions adjacent to the pustules of P. euvitis. Even in low disease severities, reductions in carbohydrates accumulation of in roots are already observed. P. viticola reduced Vcmax by 23.5% in infected leaves compared to healthy leaves. P. viticola reduced the root biomass and carbohydrate amounts in the roots of potted plants and plants in the field in the year of high disease severity. Field plants with mildew symptoms produced on average 0.5 kg less than healthy plantsand the main cause of reduction in production was the drop of berries caused by infection of P. viticola in the clusters. A simulation model for Vitis labrusca was developed using Stella ® software. The production, partitioning and dynamics of grapevine biomass was simulated over 20 years and the effects of P. euvitis and P. viticola on the reduction of healthy green plant tissue and photosynthetic efficiency, the assimilative sapper, leaf senescence acceleration and fruit drop were coupled in the model.
50

Towards a plant-based method of guiding CO₂ enrichment in greenhouse tomato

Edwards, Diane Roselyn 05 1900 (has links)
Atmospheric CO₂ enrichment is employed by greenhouse tomato growers to increase fruit yields, and CO₂ applications are managed according to atmospheric set points or CO₂ injection rates. These methods do not immediately focus on the targets of CO₂ applications: plant performance and the regulation of plant carbon status. This thesis explores several plant-based approaches that may have potential for use in the management of CO₂ in greenhouse tomato production. Three plant-based approaches to CO₂ management were explored in commercial and experimental tomato greenhouses. These were: (1) simulation modeling, (2) non-destructive analysis of growth and (3) the status of plant carbon reserves. A cost and benefit analysis (c/b) using simulation modeling was carried out using grower-collected greenhouse environment and yield data. Simulation modeling was useful for retrospectively determining c/b of several CO₂ scenarios. The model was effective in predicting long term yields, but not short term yield variations, which limits its application for CO₂ management. Non-destructive measures of growth: stem length and diameter, leaf area and fruit load were found to be too sluggish for daily CO₂ dosing decision-making. Finally, plants growing under CO₂ enrichment can deposit substantial carbon as starch in their leaves. Plant carbon status was evaluated by determining the spatial distribution of leaf starch in the shoot and by following its variation diurnally and after the onset of CO₂ enrichment. As starch is difficult to measure by a grower, leaf mass per unit area (LMA) was also monitored for assessment as a surrogate measure for starch. Leaves in positions 7 to 9 were identified as the most meaningful in the shoot to sample. Diurnal profiles indicated these leaves carryover substantial starch from one day to the next. Monitoring starch at its peak time of accumulation (14 h to 16 h), at sunset and sunrise will indicate how much the peak starch reserves are used overnight. If starch remains high between peak and sunrise the following day, then the plants are in a carbon-surplus state and CO₂ enrichment could be postponed. For upper canopy leaves LMA is substantially influenced by starch and thus is a promising surrogate.

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