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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.
81

Improvised incendiary devices risk assessment, threats, vulnerabilities and consequences

Raynis, Stephen A. 09 1900 (has links)
CHDS State/Local / The current trend in terrorist tactics is the use of simple, inexpensive and conventional weapons. One such weapon is improvised incendiary devices (IIDs). The homeland security community has underestimated the magnitude of the threat. Policy makers must recognize the potential for terrorist cells to use IIDs to create terror and fear in the public. IIDs have the potential to create devastating fires resulting in mass casualties. In addition to evaluating the risk of an IID attack and determining the state of preparedness of first responders, this thesis includes a proposal for the creation of two new national planning scenarios, urban and wildland conflagrations or firestorms. Recommendations will include incendiary protocols in the weapon of mass destruction matrix as represented by "I" in CBIRNE. This organizational change can be applied to the homeland security strategies, lexicons and documents of Federal, State, and local governments and the private sector to address the IID threat. This thesis is intended to serve as a catalyst for the Department of Homeland Security to set policy that will decrease vulnerabilities and consequences of this lesser-known threat. / Battalion Chief, New York City Fire Department (FDNY)
82

Transport and dispersion of fire extinguishing agents downstream from clutter elements of aircraft engine nacelles

Unknown Date (has links)
The combination of highly turbulent airflow, flammable fluids, and numerous ignition sources makes aircraft engine nacelles a difficult fire zone to protect. Better understanding of nacelle air flow and how it influences the spread of fires and fire extinguishing agents is needed to improve the efficiency of fire suppression. The first objective was to establish a CFD model for a flow field test section to analyze the transport and dispersion of fire extinguishing agents in the presence of various clutter elements. To validate the use of the CFD model, the simulation results of the CFD model were compared to the experimental data and they show an agreement with the experimental data. The second objective was to present parametric studies to show the effects of the coflow speed, turbulence intensity and agent droplet size on the transport and dispersion of the agent particles downstream from the clutter elements. / by Khaled Zbeeb. / Thesis (M.S.C.S.)--Florida Atlantic University, 2009. / Includes bibliography. / Electronic reproduction. Boca Raton, Fla., 2009. Mode of access: World Wide Web.
83

A Study on Pulsation In Runehamar Tunnel Fire Tests With Forced Longitudinal Ventilation

Kim, Mihyun Esther 05 October 2006 (has links)
"Fire tests involving heavy goods vehicles (HGVs) in a road tunnel with forced ventilation in Norway, conducted by SP, demonstrated a pulsation phenomena that is similar to oscillating flames and thermo-acoustic instabilities previously observed in vitiated compartments and resonant systems that meet the Rayleigh criterion, respectively. This current study investigates whether the causal phenomena can be determined using either a simple, one-dimensional fluid dynamics model or a computation fluid dynamics program. It is assumed that the leading cause for pulsation is a locally under-ventilated fire. Theoretical analysis shows that this assumption is valid and how such conditions can cause the flow field to change. A simple model is developed for a tunnel fire with forced, longitudinal ventilation. The results qualitatively represent the test data and support the assumption of a locally vitiated fire. A more sophisticated analysis, involving the Fire Dynamics Simulator (FDS) Version 4.0, provides similar results. Although FDS calibration, using similar experiment data from the Memorial Tunnel Ventilation Test Program, demonstrates model limitations in predicting smoke layers near the solid boundaries under forced flow field, the qualitative results from both models indicates that pulsation in large tunnel fires under forced ventilation conditions results from poor mixing of the bulk flow in the near field of the fire."
84

Tung Chung Fire Safety Research & Promotion Centre

Lee, Chi-hang, Joseph, 李志恒 January 2000 (has links)
published_or_final_version / Architecture / Master / Master of Architecture
85

The detection of fires under high voltage transmission lines.

Evert, Cecil Richard. January 2003 (has links)
Fires generate heat and propel burning material into the air above and around the core of the fire. Fires under power lines reduce the breakdown strength of the air insulation due to the influence the heat and particles have on the electric field surrounding the conductors. The result can be flashovers and undesirable power supply interruptions in the electrical transmission network with a considerable impact on Eskom's 275 kV and 400 kV MTS (main transmission system) networks. Eskom typically experiences a loss in sales, a reduction in the quality of the power supplied to consumers and disgruntled consumers who in turn experience financial losses due to a loss in production. In this thesis, the high frequency characteristics of corona and electrical discharges generated by the fire phenomena are studied. The influence of the operating voltages on the electric fields, the potential of different media to initiate ionisation and comparison of conductor construction (bundling and diameter) are all considered in the measurement of high frequency signals in the range of frequencies available in the tuned circuits connected to power lines. The propagation of these high frequency signals is studied both in isolation of other sources of high frequency signals (within controlled laboratory conditions) and in the real environment adjacent to all other interfering sources. Finally the fingerprinting of the varying high frequency signal patterns associated with fires is considered with a view to implementing an operational early detection device. Early detection of a fire allows the utility to understand the source of a system fault, manage it effectively and if possible pre-empt possible failure by means of appropriately applied standard operating guidelines (SOG) to minimise the impact. / Thesis (M.Sc.Eng.)-University of Natal, Durban, 2003.
86

Radio propagation in fire environments.

Boan, Jonathan Alexander January 2009 (has links)
Radio propagation in the presence of fire is known to be problematic to communications. In this thesis we use both experimental and theoretical approaches to examine and understand radio propagation in fire environments. Propagation is examined for three small scale fires with broadband equipment operating from 50MHz to 1GHz. Results for line of sight propagation show a strong interaction of fire with electromagnetic propagation. The next section develops electromagnetic modelling of the fire environment. A model of the combustion induced plasma is developed, as well as a refractive index model of the surrounding atmosphere of a fire. Simple propagation calculations are undertaken, using the developed fire models, to provide an intial understanding of propagation in fire environments. The next portion of the thesis considers propagation using a more rigorous electromagnetic simulation technique. A modified Finite Difference Time Domain method is presented and is utilised to examine three dimensional propagation in the small scale fire experiments. The outcome is a more solid understanding of propagation and the contributing factors. The last portion of the thesis is the application of the above electromagnetic modelling and simulation methods to bushfire scenarios. Various scenarios that are problematic to radio communication are examined. Discussion and recommendations are made concerning radio communication frequency selection and considerations for propagation in fire environments. / http://proxy.library.adelaide.edu.au/login?url= http://library.adelaide.edu.au/cgi-bin/Pwebrecon.cgi?BBID=1457560 / Thesis (Ph.D.) -- University of Adelaide, School of Electrical and Electronic Engineering, 2009
87

Radio propagation in fire environments.

Boan, Jonathan Alexander January 2009 (has links)
Radio propagation in the presence of fire is known to be problematic to communications. In this thesis we use both experimental and theoretical approaches to examine and understand radio propagation in fire environments. Propagation is examined for three small scale fires with broadband equipment operating from 50MHz to 1GHz. Results for line of sight propagation show a strong interaction of fire with electromagnetic propagation. The next section develops electromagnetic modelling of the fire environment. A model of the combustion induced plasma is developed, as well as a refractive index model of the surrounding atmosphere of a fire. Simple propagation calculations are undertaken, using the developed fire models, to provide an intial understanding of propagation in fire environments. The next portion of the thesis considers propagation using a more rigorous electromagnetic simulation technique. A modified Finite Difference Time Domain method is presented and is utilised to examine three dimensional propagation in the small scale fire experiments. The outcome is a more solid understanding of propagation and the contributing factors. The last portion of the thesis is the application of the above electromagnetic modelling and simulation methods to bushfire scenarios. Various scenarios that are problematic to radio communication are examined. Discussion and recommendations are made concerning radio communication frequency selection and considerations for propagation in fire environments. / http://proxy.library.adelaide.edu.au/login?url= http://library.adelaide.edu.au/cgi-bin/Pwebrecon.cgi?BBID=1457560 / Thesis (Ph.D.) -- University of Adelaide, School of Electrical and Electronic Engineering, 2009
88

The role of fire in the Miombo forest : And the adaptation of the Community-based forest management to meet local needs

Käll, Katarina January 2006 (has links)
The Miombo forest is represented in seven countries in the subtropical area of Africa and is an example of ecosystem adapted to the disturbance of anthropogenic fire. The forest yields a number of different ecosystem goods and services including fuelwood, honey and soil protection. Fire has found a worldwide acceptance during the last decade due to deeper understanding of their role in the ecosystem. The presence of fire prevents up-building of fuel and big fires, therefore a new fire management is now seen. In general the Miombo forest is threatened by overexploitation. A similar situation was represented in Duru-Haitemba forest where the case study was situated in northern Tanzania. To conserve the forest and give the tenure of the forest to the villages in Duru-Haitemba a community-based forest management was established in the middle of 1990’s. The management succeeded to save the forest with a fire management including several methods of fire preventions and now there is a well grown Miombo forest in the area. This essay deals with the topic how the fire is affecting the Miombo forest. From there, this paper examines how the current community-based forest management is formed concerning the role of fire and the objectives of the locals. The conclusion of the essay indicates that the fire has an important role in the ecosystem of the Miombo forest and favour ecosystem dynamics and diversity of the Miombo forest. The result of the case study showed that the fire management was poorly adapted to the disturbance of fire and was not widely based on local knowledge or specific needs and objectives of the different villages.
89

Políticas públicas em educação e prevenção contra incêndio e pânico: formulação de mecanismos de avaliação e controle / Public policies in education and fire and panic prevention: formulation of estimation and control mechanisms

Schunig, Fernando Raimundo 08 December 2015 (has links)
Submitted by Neusa Fagundes (neusa.fagundes@unioeste.br) on 2018-04-04T11:41:58Z No. of bitstreams: 2 Fernando_Schunig2015.pdf: 3741151 bytes, checksum: 6834d3ce23b8cdf6c22a33d3827a3f62 (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) / Made available in DSpace on 2018-04-04T11:41:58Z (GMT). No. of bitstreams: 2 Fernando_Schunig2015.pdf: 3741151 bytes, checksum: 6834d3ce23b8cdf6c22a33d3827a3f62 (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) Previous issue date: 2015-12-08 / The fires have always been a concern for the Fire Department, however, fires still going on, people lose their lives and property are destroyed. So that there is a change in this scenario is necessary to implement Public Policies in Education and Fire Prevention and panic, as well as setting numerical indices that serve as parameter for the establishment, development and evaluation of these policies. Once defined an index, it will be possible to evaluate the safety of the building due to the preventive measures and potential hazards, determination of mitigating actions the risk of fire and its use for the development of actions aimed at education on fire prevention. The objective of this research is to study the feasibility of using the evaluation index of fire risk obtained by Gretener method, adapted to serve as a numerical indicator for the establishment, development and evaluation of public policies in education and fire prevention and panic. For this survey, a comprehensive theoretical study on the subject was made to trace current expectations of Fire Prevention Panic and also carried out a field survey that realized own survey of the application, with the public researched firefighters, engineers and architects working in the analysis and preparation of Safety Plans Fire and Panic in Cascavel. As a result, it was evident that the risk assessment index fires Gretener method, adapted to the current legislation in the State of Paraná can be used widely for the formulation and evaluation of public policies in education and fire prevention and panic because it meets all conceptual and methodological requirements, and may be a useful mechanism for planning, representing a great potential for public policy establishment. / Os incêndios sempre foram uma preocupação para o Corpo de Bombeiros, porém, incêndios continuam acontecendo, pessoas perdem suas vidas e patrimônios são destruídos. Para que ocorra uma mudança nesse cenário é necessária a implementação de Políticas Públicas em Educação e Prevenção Contra Incêndio e Pânico, assim como a definição de índices numéricos que sirvam de parâmetro para o estabelecimento, formulação e avaliação destas políticas. Uma vez definido um índice, será possível a avaliação da segurança da edificação em função das medidas preventivas e perigos potenciais, determinação de ações mitigadoras do risco de incêndio e seu emprego para o desenvolvimento de ações voltadas à educação em prevenção contra incêndio. O objetivo desta pesquisa é de estudar a viabilidade da utilização do índice de avaliação de risco de incêndio obtido pelo método de Gretener, adaptado para servir como indicador numérico para o estabelecimento, formulação e avaliação de políticas públicas em educação e prevenção contra incêndio e pânico. Para esta pesquisa, foi feito um estudo teórico abrangente sobre o tema, para traçar um cenário atual da Prevenção Contra Incêndio Pânico e, ainda, realizada uma pesquisa de campo que compreendeu a aplicação de questionário próprio, tendo como público pesquisado bombeiros militares, engenheiros e arquitetos que atuam na análise e elaboração de Planos de Segurança Contra Incêndio e Pânico no município de Cascavel. Como resultado, ficou evidenciado que o índice de avaliação de risco de incêndios do método de Gretener, adaptado à legislação vigente no Estado do Paraná pode ser utilizado amplamente para a formulação e avaliação de políticas públicas em educação e prevenção contra incêndio e pânico, pois atende a todos os requisitos conceituais e metodológicos, podendo ser um mecanismo útil ao planejamento, representando um grande potencial para o estabelecimento de política pública.
90

Modeling Petroleum Supply Chain: Multimodal Transportation, Disruptions and Mitigation Strategies

Kazemi, Yasaman January 2016 (has links)
The petroleum industry has one of the most complex supply chains in the world. A unique characteristic of Petroleum Supply Chain (PSC) is the high degree of uncertainty which propagates through the network. Therefore, it is necessary to develop quantitative models aiming at optimizing the network and managing logistics operations. This work proposes a deterministic Mixed Integer Linear Program (MILP) model for downstream PSC to determine the optimal distribution center (DC) locations, capacities, transportation modes, and transfer volumes. Three products are considered in this study: gasoline, diesel, and jet fuel. The model minimizes multi-echelon multi-product cost along the refineries, distribution centers, transportation modes and demand nodes. The relationship between strategic planning and multimodal transportation is further elucidated. Furthermore, this work proposes a two stage Stochastic Mixed Integer Linear Program (SMILP) models with recourse for PSC under the risk of random disruptions, and a two stage Stochastic Linear Program (SLP) model with recourse under the risk of anticipated disruptions, namely hurricanes. Two separate types of mitigation strategies – proactive and reactive – are proposed in each model based on the type of disruption. The SMILP model determines optimal DC locations and capacities in the first stage and utilizes multimode transportation as the reactive mitigation strategy in the second stage to allocate transfer volumes. The SLP model uses proactive mitigation strategies in the first stage and employs multimode transportation as the reactive mitigation strategy. The goal of both stochastic models is to minimize the expected total supply chain costs under uncertainty. The proposed models are tested with real data from two sections of the U.S. petroleum industry, PADD 3 and PADD 1, and transportation networks within Geographic Information System (GIS). It involves supply at the existing refineries, proposed DCs and demand nodes. GIS is used to analyze spatial data and to map refineries, DCs and demand nodes to visualize the process. Sensitivity analysis is conducted to asses supply chain performance in response to changes in key parameters of proposed models to provide insights on PSC decisions, and to demonstrate the impact of key parameters on PSC decisions and total cost. / Upper Great Plains Transportation Institute (UGPTI) / Mountain Plains Consortium (MPC)

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