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Churchill residents' use of the lower Churchill River in ManitobaEdye-Rowntree, Joel 14 September 2007 (has links)
The lower Churchill River has been an important travel route for people living in its vicinity for a long period of time. Churchillians’ have used it for subsistence harvesting, as their potable water source and as a place of recreation and relaxation. Previous research has documented the importance of the Churchill River to the residents and has explored how the Churchill River Diversion affected the community of Churchill (Boothroyd, 1992; 2000; Four Directions Consulting Group, 1994; 1995).
The purpose of this project was to identify how Churchill residents used the lower Churchill River (from 1970 to 2006), recognizing three distinct periods of time. Twenty interviews were conducted with former or current long-term residents of Churchill, as well as two interviews with experts on issues concerning the lower Churchill River.
Many interviewees stated that additional negotiations and measures are required before they deem the mitigation compensation package from Manitoba Hydro to be adequate considering the impact of the diversion on the residents of Churchill. / October 2007
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Reaction of sulfur dioxide (SO2) with reversible ionic liquids (RevILs) for carbon dioxide (CO2) captureMomin, Farhana 02 February 2012 (has links)
Silylated amines, also known as reversible ionic liquids (RevILs), have been designed and structurally modified by our group for potential use as solvents for CO₂ capture from flue gas. An ideal CO₂ capture ionic liquid should be able to selectively and reversibly capture CO₂ and have tolerance for other components in flue gas, including SO₂, NO₂, and O₂. In this project, we study the reactivity, selectivity, uptake capacity, and reversibility of RevILs in the presence of pure SO₂ and mixed gas streams tosimulate flue gas compositions. Tripropylsilylamine (TPSA), a candidate CO₂ capture RevIL, reacts with pure SO₂ to form an ionic liquid consisting of an ammonium group and a salfamate group, supported by IR and NMR results. The resulting IL with pure SO₂ partially reverses when heated to temperatures of upto 500 C in the TGA. TGA analysis of the ionic liquid formed from a 4 vol% SO₂ in CO₂ mixture indicates a possible reversal temperature in the 86-163 C range.
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Kvalitetsgranskning av skadeförebyggande åtgärdsförslag i miljökonsekvensbeskrivningarWesterström, Ylva January 2011 (has links)
I en miljökonsekvensbeskrivning, MKB ska en beskrivning av planerade åtgärder ges för att undvika, minska eller avhjälpa skadliga verkningar, då projektet antas medföra betydande miljöpåverkan. Eftersom det upptäckts allvarliga brister för skadeförebyggande åtgärder i forskningsrapporter utomlands, var det intressant att undersöka åtgärdskvalitén i några svenska MKB. Svagheter och styrkor i skadeförebyggande åtgärder i 6st MKB för 2st markkabelanläggningar i Sverige undersöktes. Metoden för undersökningen var två fallstudier som jämfördes mot varandra och analyserades mot teorier. Resultatet visade att kvalitén på det undersökta materialet var övervägande bra, jämförelsevis mot de forskningsrapporter som visat på bristfälliga åtgärdsförslag utomlands. Det var väl beskrivna åtgärder där identifiering och implementering av skadeförebyggande åtgärder skedde i ett tidigt skede, enligt Mitchells åtgärdshierarki. Det fanns dock brister som stämde överens mot nämnda forskningsrapporter i uppsatsen: Otydlighet i beskrivningen om hur en särskild miljöaspekt skulle åtgärdas samt avsaknad av åtgärder för denna specifika miljöaspekt, var en stor avvikelse mot de annars välbeskrivna åtgärdsförslagen mot betydande miljöpåverkan i föreliggande undersökning. Otydlighet om åtgärderna bara var förslag eller om de skulle användas, var den brist som ansågs allvarligast för att en MKB skulle vara verkningsfull. Denna allvarliga brist var gemensam för miljökonsekvensbeskrivningarna i föreliggande undersökning och för nämnda forskningsrapporter i uppsatsen. / In an environmental impact assessment, EIA there must be a description of planned measures to avoid, minimize and repair consequences that are damaging, when a project is presumed to bring significant environmental impact. Since detecting serious lack of failure for mitigation measures in science rapports abroad, it was interesting to investigate the quality for mitigation measures for some Swedish EIA. The weakness and strengths in mitigation measures in 6 EIA for 2 ground cable structure in Sweden was examined. The method for this study was two case studies that was compared against each other and analysed with theories. The results showed that the quality of the test material was considered good, comparatively to the research that demonstrated the lack of proposals for action abroad. It was well described measures in which the identification and implementation of mitigation measures were made at an early stage, according to Mitchell's mitigation hierarchy. However, there were deficiencies that were consistent with the mentioned research in this paper: Opaque in the description of how a particular environmental aspect would be addressed and the lack of action for this particular environmental aspect, was a major deviation from the otherwise well described action proposals for significant environmental effects in this study. Opaque if the measures were just proposals or if they would be used, where the shortage was most serious for an EIA would be effective. This serious deficiency was common for the environmental impact assessments in the present study and that research reports in the paper.
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Development and Evaluation of Multiple Objects Collision Mitigation by Braking Algorithms / Utveckling och utvärdering av CMbB-algoritmer för multipla objektKivrikis, Andreas, Tjernström, Johan January 2004 (has links)
A CMbB system is a system that with the help of sensors in the front of a car detects when a collision in unavoidable. When a situation like that is detected, the brakes are activated. The decision of whether to activate the brakes or not is taken by a piece of software called a decision maker. This software continuously checks for routes that would avoid an object in front of the car and as long as a path is found nothing is done. Volvo has been investigating several different CMbB-systems, and the research done by Volvo has previously focused on decision makers that only consider one object in front of the car. By instead taking all present objects in consideration, it should be possible to detect an imminent collision earlier. Volvo has developed some prototypes but needed help evaluating their performance. As part of this thesis a testing method was developed. The idea was to test as many cases as possible but as the objects’ possible states increase, the number of test cases quickly becomes huge. Different ways of removing irrelevant test cases were developed and when these ideas were realized in a test bench, it showed that about 98 % of the test cases could be removed. The test results showed that there is clearly an advantage to consider many objects if the cost of increased complexity in the decision maker is not too big. However, the risk of false alarms is high with the current decision makers and several possible improvements have therefore been suggested.
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Integrating Mitigation and Adaptation to Climate Change in Orissa, India: Coupling Entrepreneurial Agricultural Mechanization with Village-Based Biodiesel ProductionDabby, Nava Samara 07 September 2010 (has links)
India’s strong agrarian economy, global location and climatic zoning make it highly vulnerable to the potential effects of climate change. Recent evidence of shortening cropping seasons has raised interest among academics and policy makers in tools for adaptation. Timely sowing and appropriate mechanization have been identified as attractive adaptation tools. Mechanization using locally produced biodiesel in place of conventional fossil fuel provides a relatively low-cost and sustainable opportunity to mitigate carbon emissions. An enterprise model in which farmers invest in machinery for custom hire coupled with community-produced biodiesel offers one approach to integrated adaptation and mitigation mechanisms for climate change.
This research analyses agricultural practices and small farm mechanization in the state of Orissa, India, drawing on a village case study. Primary data is from twelve key informant interviews with farmers, academics and NGO representatives in India. Secondary data analysis includes Indian and Orissan government documents and reports from international organizations regarding agricultural mechanization, sustainability, resiliency and climate change.
The results of this study indicate that joint mitigation and adaptation mechanisms implemented at the community level can address impacts of climate change while also offering opportunities for livelihood benefits, poverty alleviation and income generation. This research contributes to growing literature on adaptation and mitigation tools for climate change and adds an integral focus on small-scale opportunities within the broader scope of sustainable agriculture and biofuel development in India.
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Studies in Wireless Home Networking Including Coexistence of UWB and IEEE 802.11a SystemsFiroozbakhsh, Babak 25 January 2007 (has links)
Characteristics of wireless home and office services and the corresponding networking issues are discussed. Local Area Networking (LAN) and Personal Area Networking (PAN) technologies such as IEEE 802.11 and Ultra Wideband (UWB) are introduced. IEEE 802.11a and UWB systems are susceptible to interference from each other due to their overlapping frequencies. The major contribution of this work is to provide a framework for coexistence of the two systems. The interference between the two systems is evaluated theoretically by developing analytical models, and by simulations. It is shown that the interference from UWB on IEEE 802.11a systems is generally insignificant. IEEE 802.11a interference on UWB systems, however, is very critical and can significantly increase the bit error rate (BER) and degrade the throughput of the UWB system. A novel idea in the MAC layer is presented to mitigate this interference by means of temporal separation. Simulation results validate our technique. Implications to wireless home services such as high definition television (HDTV) are provided. Future research directions are discussed.
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Characterization of Section 404 Permit Mitigation Plans, Coastal Margin and Associated Watersheds, Upper Texas CoastConkey, April A. 14 January 2010 (has links)
A predicted loss of agricultural rice-wetlands and increasing urbanization and development threatens the remaining freshwater wetlands along the upper Texas coast. To avoid, minimize, and mitigate wetland loss, the U.S. Army Corps of Engineers (Corps) is directed to enforce Section 404 of the Clean Water Act (1975 amendment) by administering permits for development. Furthermore, a 1990 Memorandum of Agreement (MOA) between the Corps and the U.S. Environmental Protection Agency (EPA) proposed a national goal of no net wetland loss (NNL). My goals were to identify the frequency of occurrence of freshwater wetland loss due to dredge or fill, assess final plans to mitigate wetland loss, and verify the persistence of the created compensatory wetlands. I created a database of 96 individual, Section 404 permits issued from 1981 to 2001 in the counties of Chambers, Hardin, Jefferson, Liberty, Montgomery, Orange, and San Jacinto (Galveston District Office, U.S. Army Corps of Engineers). Descriptive statistics were calculated for permit characteristics in relation to issue date (pre- or post-NNL). Public comments received from national and state agencies were rank ordered against mitigation plan type to determine Spearman's Rank Order Correlation Coefficient. Visual identification (via site visits and 1996 aerial photos) was used to validate compensatory wetland persistence. Shoreline protection of private property and oil and gas drilling (64% of permit applicants and 59% of impacts) had the greatest effect on wetland loss in the region, particularly Chambers, Jefferson, and Montgomery counties. Overall, 79.3 ha of freshwater wetlands were gained; however, gain was overestimated due to large projects for habitat enhancement. Permits issued post-NNL were more likely to have formal mitigation plans (58% vs. 13% pre-NNL) and allowed no net wetland loss. Although agency comments recommending more formal mitigation plans increased after NNL, only a weak positive correlation was detected (Spearman's r less than or equal to 0.4). Six of seven created wetlands remained in existence through 2006 though they are freshwater ponds replacing more diverse aquatic systems. I recommend the development of a comprehensive method to track wetland loss, mitigation, and changes in watersheds over time.
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The application of expansion foam on liquefied natural gas (LNG) to suppress LNG vapor and LNG pool fire thermal radiationSuardin, Jaffee Arizon 15 May 2009 (has links)
Liquefied Natural Gas (LNG) hazards include LNG flammable vapor dispersion and
LNG pool fire thermal radiation. A large LNG pool fire emits high thermal radiation
thus preventing fire fighters from approaching and extinguishing the fire. One of the
strategies used in the LNG industry and recommended by federal regulation National
Fire Protection Association (NFPA) 59A is to use expansion foam to suppress LNG
vapors and to control LNG fire by reducing the fire size.
In its application, expansion foam effectiveness heavily depends on application rate,
generator location, and LNG containment pit design. Complicated phenomena involved
and previous studies have not completely filled the gaps increases the needs for LNG
field experiments involving expansion foam. In addition, alternative LNG vapor
dispersion and pool fire suppression methodology, Foamglas® pool fire suppression
(PFS), is investigated as well.
This dissertation details the research and experiment development. Results regarding
important phenomena are presented and discussed. Foamglas® PFS effectiveness is
described. Recommendations for advancing current guidelines in LNG vapor dispersion
and pool fire suppression methods are developed. The gaps are presented as the future
work and recommendation on how to do the experiment better in the future. This will
benefit LNG industries to enhance its safety system and to make LNG facilities safer.
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Interdependent infrastructures and multi-mode attacks and failures: improving the security of urban water systems and fire responseBristow, Elizabeth Catherine 15 May 2009 (has links)
This dissertation examines the interdependence between urban water distribution
systems and urban fire response. The focus on interdependent critical infrastructures is
driven by concern for security of water systems and the effects on related infrastructures
if water distribution systems are damaged by terrorist attack or natural disaster.
A model of interdependent infrastructures (principally water distribution systems
and fire response) is developed called the Model of Urban Fire Spread (MUFS). The
model includes the capacity to simulate firefighting water demands in a community
water system hydraulic model, building-to-building urban fire spread, and suppression
activities. MUFS is an improvement over previous similar models because it allows
simulation of urban fires at the level of individual buildings and it permits simulation of
interdependent infrastructures working in concert.
MUFS is used to simulate a series of multi-mode attacks and failures (MMAFs) –
events which disable the water distribution system and simultaneously ignite an urban
fire. The consequences of MMAF scenarios are analyzed to determine the most serious modes of infrastructure failure and urban fire ignition. Various methods to determine
worst-case configurations of urban fire ignition points are also examined.
These MMAF scenarios are used to inform the design of potential mitigation
measures to decrease the consequences of the urban fire. The effectiveness of mitigation
methods is determined using the MUFS simulation tool. Novel metrics are developed to
quantify the effectiveness of the mitigation methods from the time-series development of
their consequences. A cost-benefit analysis of the various mitigation measures is
conducted to provide additional insight into the methods’ effectiveness and better inform
the decision-making process of selecting mitigation methods.
Planned future work includes further refinement of the representation of fire
propagation and suppression in MUFS and investigation of historical MMAF events to
validate simulation predictions. Future efforts will continue development of appropriate
optimization methods for determining worst-case MMAF scenarios.
This work should be of interest to water utility managers and emergency
planners, who can adapt the methodology to analyze their communities’ vulnerability to
MMAFs and design mitigation techniques to meet their unique needs, as well as to
researchers interested in infrastructure modeling and disaster simulation.
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Integrated Economic-Epidemic Modeling of Avian Influenza Mitigation Options: A Case Study of an Outbreak in TexasEgbendewe-Mondzozo, Aklesso 2009 December 1900 (has links)
Recent World Animal Health Organization (OIE) reports on Avian Influenza (AI) outbreaks in Asia, Europe and Canada suggest that there is a nonzero probability that an
outbreak may occur anywhere in the world, including the US. To help evaluate possible policy in the face of such an event, this dissertation does an economic evaluation of the implications of using two mitigation strategies: one corresponding to the currently response strategy; and the other an OIE recommended one utilizing vaccination. To do this, the dissertation develops and uses an integrated economic-epidemic model. In this
effort, I first estimate the cost of an AI outbreak under a deterministic disease spread assumption where a new vaccination strategy and the current strategy are compared. Subsequently, I introduce risk in the model and construct 95 percent confidence intervals for
the outbreak costs, and I rank the outcomes of the alternative strategies using stochastic dominance criteria. In addition, during both phases, I develop and estimate the breakeven probability for an event where ex-ante fixed costs of vaccine stockpiling are
justified by the reduction in disease event damages.
Results under deterministic disease spread assumption suggest that the vaccination strategy lowers the cost of outbreaks as opposed to the current strategy. This
happens because vaccination reduces the number of culled and quarantined flocks. The study is conducted in three locations, yielding the finding that the costs of an outbreak vary depending on the densities of poultry flocks. I also find that when consumer
demand shifts due to the outbreak, the costs are much larger. Finally, I find that ex-ante
vaccine stockpiling is justified for all the sub-regions if the probability of outbreak
exceeds 0.07.
The stochastic disease spread assumption results also show that the vaccination
strategy dominates in first degree stochastic dominance sense. Consistent with stochastic
dominance results, the 95 percent confidence intervals have narrower ranges under the
vaccination strategy than without it. Finally, the distribution of the breakeven probability
for vaccine stocking has a mode of 0.07 and that the probability is accurate with 82 percent
likelihood. However, the threshold varies with the disease transmission parameters and
could reach up to 0.32.
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