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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.
61

Three Essays on Complex Systems: Self-Sorting in a One-Dimensional Gas, Collective Motion in a Two-Dimensional Ensemble of Disks, and Environment-Driven Seasonality of Mosquito Abundance

Young, Alexander L., Young, Alexander L. January 2017 (has links)
Complex systems offer broad, unique research challenges due to their inability to be understood through a classic reductionist perspective, as they exhibit emergent phenomena that arise through the interactions of their components. In this thesis, we briefly review some characteristics of complex systems and the interplay of mathematical and computational methods to study them. We then discuss these approaches, how they are implemented, and how they support one another in three settings. First, we present a study that connects weather data to seasonal population-abundance of mosquitoes, using a microscopic model. Secondly, we consider the collective motions that arise in ensembles of disks interacting through non-elastic collisions and investigate how such behaviors affect macroscopic transport properties. Finally, we consider a 'self-sorting' one-dimensional collection of point-particles. In all of these cases, agent-based models and simulations are used to guide analysis, and in the final example, we explain how the simulations led to new theorems. Articles and molecular dynamics computer codes are provided as appendices.
62

AGENT-BASED MODELING TO ASSESS THE EFFECTIVENESS OFRUN HIDE FIGHT

Jae Yong Lee (6618806) 15 May 2019 (has links)
<div>The 1999 Columbine High School shooting was a bold reminder which emphasized the importance of active shooter preparedness for the first responder communities and the general public. Since Columbine, the preparedness for active shooter incidents (ASIs) both in the public and private sectors proactively took place. Currently, the RUN.HIDE.FIGHT.{\textregistered} (RHF) response for unarmed individuals is implemented as part of the emergency response throughout the United States. Despite the RHF's nationwide implementation, there is a lack of literature that supports the effectiveness of RHF to lower casualty rates during ASIs. </div><div></div><div>This thesis examined casualty differences of RHF and the shooters' discharge interval by creating the incidents that have occurred in the library during the 1999 Columbine High School shooting with AnyLogic's agent-based modeling capabilities. Recreating ASI in a virtual environment naturally removes the participants’ physiological and psychological implications. Additionally, the flexibility of agent-based modeling allows validating the model based on the historical events than to run various what-if scenarios. The outcome of this thesis examines the effectiveness of RHF by comparing the output data from the actual event to models with RHF implementation.</div>
63

A Simulation-Based Design and Evaluation Framework for Energy Product-Service System in Liberalized Electricity Markets / シミュレーションに基づく自由化された電力市場におけるエネルギー製品サービスシステムの設計および評価フレームワーク

Widha, Kusumaningdyah 23 March 2021 (has links)
京都大学 / 新制・課程博士 / 博士(エネルギー科学) / 甲第23294号 / エネ博第419号 / 新制||エネ||79(附属図書館) / 京都大学大学院エネルギー科学研究科エネルギー社会・環境科学専攻 / (主査)教授 手塚 哲央, 教授 宇根﨑 博信, 准教授 MCLELLAN Benjamin / 学位規則第4条第1項該当 / Doctor of Energy Science / Kyoto University / DFAM
64

Evaluation of the Evacuation of Essential Buildings: Interaction of Structural and Human Behaviour through Nonlinear Time-History Analysis and Agent-Based Modelling

Delgado, M., Delgado, M., Rosales, A., Arana, V. 07 February 2020 (has links)
In this article, a performance assessment of the evacuation system is established for educational buildings. Structural and geotechnical information of the building is collected and introduced into a database. A similar procedure was realized for the information related to the occupants. Using this information, a) the structural fragility and localized collapse were determined and b) the interaction of the person with the partial collapse was established. For the first aspect, nonlinear time history was used, and for the second, the agent-based modeling was applied to recreate the reaction of people that face the micro collapse. Therefore, the important results of this evaluation are: 1) To localize collapsed beans and columns that make inoperable evacuation routes, 2) to localize bottleneck areas that people concentration during evacuation, and 3) quantification of affected people, in terms of persons caught up in the building that cannot evacuate.
65

Multiagentní modelování a jeho využití v sociologii / Agent-Based Modelling and Its Use in Sociology

Kudrnáčová, Michaela January 2019 (has links)
Master thesis elaborates on agent-based modelling (ABM, computer simulation method) founded on the concept of analytical sociology and its use in empirical sociology. The use is demonstrated by creation of a model based on the principal of environmental sociology studying the influence of social factors on the environment. Thesis works with the empirical- theoretical concept New ecological paradigm (NEP) measuring the values and opinions on the environment. The origin of the paper was motivated by the absence of the projects combining the method of empirically calibrated agent-based modelling and sociological grounds, particularly in the Czech context, but also abroad. Based on the environmental module of Czech data ISSP 2010 and research question "How parameters of social network influence the willingness to sort waste?" model was created and analyzed. Relationship between both types of agents (sorting and not sorting waste during the whole simulation) and their neighbourhood was found. The higher the number of neighbours, the more agents with this particular type of behaviour. The likelihood of bond creation with long-distance agent at the expence of bond abolition with close neighbour was without any influence on the number of non/sorting agents. It seems the agents tend to replicate behaviour...
66

Social and ecological dynamics of forager mobility: An agent-based modeling study of Middle Stone Age archaeology in southern Africa

Peart, Daniel Chad January 2021 (has links)
No description available.
67

Development of a decision support tool for transit network design evaluation

Mzengereza, Isaac 06 March 2022 (has links)
Municipalities increasingly have less financial resources to spend on implementation of transport strategies and plans. This situation is putting pressure on transport professionals to minimize wasteful expenditure on projects that do not deliver high transport service improvements. As such, the need for efficient, pragmatic decision making on policy direction, infrastructure expenditure, or any transport interventions is becoming very critical. Thus, transport professionals are increasingly in need of tools to help them predict with increased accuracy the outcomes of their intended transport interventions. The City of Cape Town has a Bus Rapid Transport system called MyCiTi. Current MyCiTi operations are incurring losses. The service is kept running on the back of subsidies from the federal government. There is a need for rationalization of the system. However, with strained resources, the interventions on the system have to guarantee improvements. Overemphasis on the ability of MyCiTi BRT service to support transportation during the 2010 soccer world cup event heavily influenced the design of the network. As a result, network appraisal is one area that can be done on the system to identify areas of improvement. In this thesis, decision making support will be demonstrated using a network design appraisal process for the MyCiTi BRT system in Cape Town. The existing MyCiTi network will undergo network improvement using heuristic node insertion technique leading to multiple network scenarios in a modeling environment. Agent-Based demand mobility behavior simulation will be used on each of the network scenarios to come up with network performance indicators. These network performance indicators will be used in the multi-criteria decision analysis (MCDA) model to come up with a ranking of the network scenarios and help in deciding on the optimum network improvement intervention. Overall, findings of this research show the importance of weighting of the performance indicators. Where networks that score well in the performance indicator with the high weights also rank high. In conclusion, the study has demonstrated the importance of decision making support in interventions on complex systems like bus systems. Recommendations on the possible avenues of research stemming from this thesis have also been outlined.
68

Bottom-up Ecology: An Agent-Based Model on the Interactions Between Competition and Predation

Karsai, Istvan, Montano, Emil, Schmickl, Thomas 01 January 2016 (has links)
Published by Informa UK Limited, trading as Taylor & Francis Group. We developed an agent-based computer model of an ecosystem to predict interactions of competition and predation. In our simulations of the model, the effects of the ‘Gause law’ emerged as the results of population fluctuations and a large number of stochastic events. Small biases in life history parameters produced strong effects through the interactions of positive feedback with the population fluctuations. In a low-production environment, the smaller and faster consumer outcompetes the larger and slower one, but in a high production environment the larger and slower consumer survives. Predation hastens the extinction of one of the consumers, but niche partitioning of the consumers increases both the coexistence of consumers and the number of predators. Predators with medium efficiency are able to coexist in the system longer and in larger numbers. Besides the ecological insights this model provides, we conclude that agent-based simulations are very effective tools to explore the interactions between predation and competition interactions.
69

Drone observation reveals a multilevel society of feral horses / ドローンによる観察が明らかにするウマの重層社会

Maeda, Tamao 23 March 2023 (has links)
付記する学位プログラム名: 霊長類学・ワイルドライフサイエンス・リーディング大学院 / 京都大学 / 新制・課程博士 / 博士(理学) / 甲第24469号 / 理博第4968号 / 新制||理||1709(附属図書館) / 京都大学大学院理学研究科生物科学専攻 / (主査)教授 平田 聡, 教授 伊谷 原一, 教授 村山 美穂 / 学位規則第4条第1項該当 / Doctor of Science / Kyoto University / DGAM
70

Simulating Spatial and Temporal Flood Risk Dynamics with a Coupled Agent-Based and Hydraulic Model

Michaelis, Tamara January 2019 (has links)
Floods are one of the most costly natural hazards worldwide, affecting millions of people every year. Flood risk management is of global concern, and a deeper understanding of dynamic flood risk development is needed. Currently,vulnerability and exposure are often assumed to be constant in quantitative flood risk assessments, which does not reflect patterns observed in real life. In fact, flood protection measures on individual and community level can induce changes in both vulnerability and exposure, as well as alter river and floodplain hydraulics. The human-flood system is complex, incorporating two-way interactions between both subsystems. To build up these dynamics from the bottom up with a focus on the role of the individual, an agent-based model was combined with a hydraulic model. It was shown that this coupled model is capable of replicating levee and adaptation effects which are commonly knownto occur in the context of river floods and flood protection measures. Moreover,the new modeling approach can explicitly simulate the spatial distribution of flood risk which allowed for an analysis of conflicting interests in urban and rural areas. Here, model outcomes suggest that a shift of flood risk from high-value urban to lower-value rural areas can reduce system-wide flood losses. However, decreasing flood awareness in the city will push population growth rates, and discontent in rural areas might nally induce a shift of higher floodrisk back to the urban area. In the end, one low-probability high-intensity event might cause a disastrous outcome.

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