ITC/USA 2009 Conference Proceedings / The Forty-Fifth Annual International Telemetering Conference and Technical Exhibition / October 26-29, 2009 / Riviera Hotel & Convention Center, Las Vegas, Nevada / Following-up on an ITC 2006 paper, "From RF to bits with Synthetic Beamforming", we follow the development and fielding of a Digital Beamforming (DBF) Antenna. This antenna, built for an airborne Telemetry application, supports 10 individual polarization-diverse beams and immediately converts RF to IF at the antenna element through a suite of LNBs. The IF is then digitized and all subsequent processing is performed through an array of 200+ FPGAs, including DBF, optimal combining, demodulation, and IF upconversion. We present our Model-Based Design approach, which allowed us to develop and test the system incrementally and rapidly, particularly during the transition from factory testing to flight operations, where several unexpected problems were discovered. Our software tool set enabled us to dissect the System behavior via post-mission replay, and our detailed simulations were instrumental in developing mitigation quickly. The System-level impacts and root causes of some of these issues are also discussed. We believe the flexibility of DBF and the modular software architecture were key in quickly mitigating many of these unforeseen real-world issues without hardware modification.

Agriculture has been reported to contribute a significant amount of greenhouse gases to the atmosphere among other anthropogenic activities. With still more than 870 million people in the world suffering from under-nutrition and a growing global food demand, it is relevant to study ways for mitigating the environmental impact of food production. The objective of this work was to identify gaps in the knowledge regarding the main factors affecting greenhouse gas (GHG) emissions from beef farming systems, to reduce the uncertainty on carbon footprint predictions, and to study the relative importance of mitigation options at the system level. A lack of information in the literature was identified regarding the quantification of the relevant animal characteristics of extensive beef systems that can impact on methane (CH4) outputs. In a meta-analysis study, it was observed that the combination of physiological stage and type of diet improved the accuracy of CH4 emission rate predictions. Furthermore, when applied to a system analysis, improved equations to predict CH4 from ruminants under different physiological stages and diet types reduced the uncertainty of whole-farm enteric CH4 predictions by up to 7% over a year. In a modelling study, it was demonstrated that variations in grazing behaviour and grazing choice have a potentially large impact upon CH4 emissions, which are not normally mentioned within carbon budget calculations at either local or national scale. Methane estimations were highly sensitive to changes in quality of the diet, highlighting the importance of considering animal selectivity on carbon budgets of heterogeneous grasslands. Part of the difficulties on collecting reliable information from grazing cattle is due to some limitations of available techniques to perform CH4 emission measurements. Thus, the potential use of a Laser Methane Detector (LMD) for remote sensing of CH4 emissions from ruminants was evaluated. A data analysis method was developed for the LMD outputs. The use of a novel technique to assess CH4 production from ruminants showed very good correlations with independent measurements in respiration chambers. Moreover, the use of this highly sensitive technique demonstrates that there is more variability associated with the pattern of CH4 emissions which cannot be explained by the feed nutritional value. Lastly, previous findings were included in a deterministic model to simulate alternative management options applied to upland beef farming systems. The success of the suggested management technologies to mitigate GHG emissions depends on the characteristics of the farms and management previously adopted. Systems with high proportion of their land unsuitable for cropping but with an efficient use of land had low and more certain GHG emissions, high human-edible returns, and small opportunities to further reduce their carbon footprint per unit of product without affecting food production, potential biodiversity conservation and the livelihood of the region. Altogether, this work helps to reduce the uncertainty of GHG predictions from beef farming systems and highlights the essential role of studies with a holistic approach to issues related to climate change that encompass the analysis of a large range of situations and management alternatives.

No description available.

<p>The old water system in Sala, formerly belonging to thesilver mine, is analysed with regard to dam safety focusing onthe hydrological aspects. The hydrological safety of the riskclass I dams in the area, built in the 16th century, is notconsidered adequate according to the Swedish guidelines fordesign flood determination. A review is made of internationalprinciples for design flood determination. The overview showsthat there is no common principle used internationally whendealing with design flood for dams. In some countries there isan ambition to implement risk assessment for evaluation ofhydrological safety. However, at present Australia is the onlycountry that has fully integrated risk assessment in theirdesign flood guidelines. A risk assessment of the water systemin Sala shows that neither increasing the spillway capacity norimplementing flood mitigation measures in the watershed haveany significant effect on dam safety in the area. Nothingindicates that watersheds with a high presence of mires, likein the Sala case, should be particularly well suited forimplementing flood mitigation in the watershed as a dam safetymeasure. In order to safely handle the design flood in Sala andavoid dam failure due to overtopping the flood needs to bediverted from the water system.</p><p><b>Key words:</b>dam safety; design flood; flood mitigation;hydrological; risk assessment</p>

The small land area of the islands of the Maldives, combined with high population density, makes the communities of these islands vulnerable to natural disaster events such as flooding and tsunami. The Indian Ocean Tsunami on 26 December 2004 impacted 69 islands of the Maldives, killing 82 people, leaving 26 people missing and 15, 000 people internally displaced, making it the worst disaster in recorded history. Following the event, the Government of the Maldives announced a Safer Island Development Programme which seeks to provide the infrastructure necessary to adapt to natural disasters. The key focus of disaster management is to reduce the vulnerability of the communities exposed to hazards and risks, and to help them to enhance their resilience. Efforts have been made to develop safer and sustainable communities in all corners of the developed and developing worlds. New Zealand Government announced its effort to build safe and secure communities in 2007 while at a local level the Christchurch City Council published the Safer Christchurch Strategy in 2005. Overseas, the Community Strategy 2000, outlines the vision of "A safe and strong Island" at Isle of Wight United Kingdom. The islands of the Maldives have natural characteristics which make them vulnerable to disasters such as tsunami. This research has been able to identify the relationship between these characteristics and the natural vulnerability of the islands using the data that was collected following the Indian Ocean Tsunami. Out of 11 island, that have been identified for the Safer Islands Development Programme, one island is found to have very high natural vulnerability and 5 islands a high natural vulnerability, from the island vulnerability index model developed through this study. The Island Vulnerability Index model could be used to enhance the present Safer Island Development Programme island selection criteria, to reduce the possibility of 'building risk' into the infrastructure development on the islands. The index could also be used in the Environmental Impact Assessment studies to address the issue of disasters, effective resources allocation in the Public Sector Infrastructure Programme for 'building back better', and resource identification in land use planning.

This thesis assesses the mitigating impact of repentance upon the fixed punishments for brigandage (hiraba), theft, and the accusation of fornication (qadhf) under Islamic law, focusing on classical sources of Qur'anic exegesis (tafsir), law (fiqh), and legal theory (usul al-fiqh). It examines and compares the opinions of jurists and exegetes who are not affiliated with a school of law as well as jurists who belong to any of the eight legal schools--namely the Hanafis, Malikis, Shafi`is, Hanbalis, Zahiris, Zaydis, Imamis, and Ibadis. This thesis demonstrates that the mitigating impact of repentance upon the fixed punishments for brigandage, theft, and qadhf constitutes a case of casuistry as jurists do not assign legal significance to the concept of repentance in all of these three cases. Furthermore, the legal tradition on the mitigating impact of repentance upon fixed punishments shows a high degree of commonality that transcends school affiliation and theological orientation.

In order to reduce the rate of climate change, particularly global warming, it is imperative that industries reduce their carbon dioxide (CO2) emissions. A promising solution of CO2 emission reduction is Carbon dioxide Capture and Storage (CCS) by sequestration, which involves isolating and extracting CO2 from the flue gases of various industrial processes, and thereafter burying the CO2 underground. The capture of CO2 proved to be the most challenging aspect of CCS. Thus, the objective of this research was to identify the most promising solution to capture CO2 from industrial processes. The study focussed on capturing CO2 emitted by coal power plants, coal-to-liquids (CTL) and gas-to-liquids (GTL) industries, which are common CO2 emitters in South Africa. This thesis consists firstly of an extensive literature review detailing the above mentioned processes, the modes of CO2 capture, and the various CO2 capture methods that are currently being investigated around the world, together with their benefits and drawbacks in terms of energy penalty, CO2 loading, absorption rate, capture efficiency, investment costs, and operating costs. Modelling, simulation, and pilot plant efforts are also described. The study reviewed many CO2 capture techniques including solvent absorption, sorbent capture, membrane usage, hydrate formation, and newly emerging capture techniques such as enzyme based systems, ionic liquids, low temperature cryogenics, CO2 anti-sublimation, artificial photosynthesis, integrated gasification steam cycle (IGSC), and chemical looping combustion The technique of solvent absorption was found to be the most promising for South African industries. Vapour-liquid-equilibrium (VLE) measurements of solvent absorption using amine blends were undertaken, using blends of methyl-diethanol amine (MDEA), diethanol amine (DEA) and water (H2O) with composition ratios of 25: 25: 50 wt% and 30: 20: 50 wt% respectively, and with CO2 and N2 gases at CO2 partial pressures of 0.5 to 10.5 bar. Experiments were conducted under system pressures of 5 to 15 bar and temperatures of 363.15 and 413.15 K, using a static analytic apparatus. CO2 liquid loading results were analysed and discussed. The experimental data were regressed in Matlab (R2009b) using the Posey-Tapperson-Rochelle model and the Deshmukh-Mather model. The Matlab programmes are presented along with the regressed binary interaction and model parameters. The accuracy of model predictions are discussed. Thereafter an Electrolyte-NRTL model regression and simulation of the absorption process was conducted using Aspen Plus V 7.1. for flue gas compositions, solvent compositions, temperature, and pressure conditions similar to that of process operating conditions. CO2 loading, design factors, CO2 recovery, and CO2 purity results were analysed and compared where appropriate, with experimental results. Finally a general preliminary energy efficiency and cost analysis was conducted based on the simulation results. The main conclusions reached are that the amine solvent blend containing 25:25:50 wt% of MDEA:DEA:H2O, produced higher CO2 loadings for its respective system conditions than other solvents studied and those found in literature. However, absorption of CO2 was found to be highly dependent on system temperature and pressure. The Deshmukh-Mather model provided higher accuracy than the Posey-Tapperson-Rochelle model, producing CO2 loading predictions with a relative error not exceeding 0.04%, in 1.5 to 3 minutes using a dual core processor. Aspen absorption simulations provided significantly lower CO2 loading results than those experimentally obtained, due to the low contact time achieved and higher temperature dependence in the proposed absorption process. Process improvements were highlighted and implemented to increase CO2 recovery and purity. Energy penalty values were found to be higher than those found in literature, but room for process and design improvement was identified and recommendations were given. Investment cost estimates were found to be justifiable and within reason. Limitations of the simulation were also identified and discussed. / Thesis (M.Sc.Eng.)-University of KwaZulu-Natal, Durban, 2010.

Climate change is one of the greatest and probably most challenging environmental, social and economical threats facing the world this century. Human activities have altered the chemical composition of the atmosphere through the buildup of significant quantities of greenhouse gases (GHGs), which remain in the atmosphere for long periods of time and intensify the natural greenhouse effect. Increasing concentrations of greenhouse gases, mainly CO2, are likely to accelerate the rate of climate change. Concerns are growing about how increases in CO2 caused by human activities are contributing to the natural greenhouse effect and raising the Earth's average temperature. Electricity generation, especially from fossil fuel, and petroleum industries contribute the most to greenhouse gases emissions in Canada. As of 2004, they contributed to about 37% of total (GHGs). Risks of climate change and subsequent future environmental regulations are pressing electricity and petroleum refining industries to minimize their greenhouse gas emissions, mainly CO2. Fossil fuel power plants and refineries are now being challenged to comply with the Kyoto protocol by the United Nations Framework Convention and Climate Change (UNFCC). Canada???s target is a reduction in CO2 emissions of 6% from 1990 level. In this thesis, an optimization approach for integrating planning and CO2 reduction is developed for electricity and refinery sectors. Three different CO2 mitigation options are considered in each case. For the electricity sector, these mitigation options were 1) fuel balancing (optimal adjustment of the operation of existing generating stations to reduce CO2 emissions without making structural changes to the fleet), 2) fuel switching (switching from carbon intensive fuel to less carbon intensive fuel, essentially switching from coal to natural gas) and 3) implementing different technologies for efficiency improvement. The optimization model takes into account meeting electricity demand and achieving a certain CO2 reduction target at a minimum overall cost. The model was formulated as a Mixed Integer Non Linear Program (MINLP) and was implemented in GAMS (General Algebraic Modeling System). Exact linearization techniques were employed to facilitate solution development. The computer program was capable of determining the best strategy or mix of strategies to meet a certain CO2 reduction target at minimum cost. The model was illustrated on a case study for Ontario Power Generation (OPG) fleet. The results showed that for 1% CO2 reduction target, only fuel balancing need to be applied and even a decrease of about 1.3% in overall cost was obtained. The optimizer chose to increase production from all non fossil fuel power plants and to decrease production from natural gas power plant. This is because natural gas is the most expensive fuel that OPG uses. For higher reduction targets, it was necessary to implement fuel switching. For 30% reduction, for example, 11 boilers out of 27 (4 are already natural gas) are switched from coal to natural gas and the cost increases by about 13%. Applying efficiency improvement technologies such as installing new turbine blades was a good option only at small reduction targets. As the reduction target increases, the optimizer chose not to implement efficiency improvement technologies and only fuel switching was the best option to select in addition to fuel balancing. For the refinery sector, a similar strategy was applied. An optimization model was developed to maximize profit from selling final products and to meet a given CO2 reduction target with products demand and specifications. Three CO2 mitigation options were considered and these were: 1) balancing that implies the increase in production from units that emit less CO2 emissions provided that demand is met, 2) fuel switching that involves switching from current carbon intensive fuel to less carbon intensive fuel such as natural gas, 3) implementation of CO2 capture technologies. Chemical absorption (MEA) process was used as the capture process. Prior to the development of the refinery planning model, a sub-model was developed for each unit in a refinery layout. Then, the sub-models were integrated into a master planning model to meet final products demand and specifications with the objective of maximizing profit without CO2 mitigation options. The model was solved first as a Non Linear Program (NLP). Then, binary variables representing the existence or no existence of fuel switching option and CO2 capture processes were introduced into the model. The model was formulated as a Mixed Integer Non Linear Program (MINLP), coded in GAMS, and applied to different case studies. The results showed that the refinery planning model tends to produce more from the most profitable product, which is gasoline, and chose to blend products into the most profitable pool unless the demand needs to be satisfied for certain other products. The model, for example, chose to send kerosene from the diesel hydrotreater to the kerosene pool and not to the diesel pool since kerosene has higher selling value than diesel. When CO2 mitigation options were introduced into the model, only 0.4% CO2 reduction was achieved by simply decreasing production from the hydrocracker (HC) unit and increasing production from the fluidized catalytic cracking (FCC) unit. This was done because the FCC unit tends to emit less CO2 compared to the HC unit. At higher reduction target such as 1%, fuel switching was implemented by choosing the FCC to run with natural gas. The profit decreased slightly because of the retrofit cost of switching. It was noticed also that fuel switching can achieve a maximum of 30% reduction in CO2 emissions. This was achieved by switching all units to run with natural gas that emits less CO2 emissions. For a reduction target higher than 30%, CO2 capture technologies need to be applied. For 60% reduction, the optimization chose to switch three units (out of 8) and to capture CO2 emissions coming from four units. Only the FCC remained unchanged. A decrease in the profit was noticed as the reduction target increases since more units need to be switched and more CO2 need to be captured. The results showed that adding sequestration cost further decreased the profit. However, it was noticed that the selling price of final products had the most effect on the profit. An increase of 20%, for example, in final products??? prices, leads to a 10% increase in profit even when the CO2 reduction target was as high as 80%. When the retrofit cost for switching and capture was decreased by 30%, the effect on the profit was noticed only at higher reduction targets since more units were switched and more CO2 capture units were implemented

The objective of this study, based on the theories of Facework (Goffman 1967) and Politeness (Brown & Levinson 1978, 1987), is to observe and establish a classification of mitigating strategies used by two groups of friends to express and deal with disagreement and criticism in French. After a critical review of the development of sociopragmatics and of essential notions for the analysis of interactions, the concept of mitigation is presented, including mitigation used in the context of disagreement and criticism. The fieldwork and the transcription process and new conventions are then presented and discussed. For the analysis, three episodes from recordings of naturally-occurring conversations between friends were selected and transcribed. The data were analysed and classified in context with a view to defining both the pragmatic functions of the various mitigators and how they tend to be used by the speakers. The results of the analysis have allowed us to establish a classification of micro-mitigating-strategies within macro-strategies, and to show that speakers were able to mitigate disagreement and criticism, in order of descending frequency, by converging towards the interlocutor, by using modalised forms, by using a didactic, clarificatory speech style, but also by realising a "décrochage énonciatif" (enunciation disconnection) and trying to avoid or minimise the Face Threatening Acts. These observations contribute to the study of mitigating disagreement and criticism among friends, provide initial evidence of a considerable variation in the use of mitigating strategies in conversational French and call for further analysis of this type of conversation in order to determine to what extent these uses of mitigators result from a social behaviour specific to this type of interactional situation or speech acts.

Master of Science / Department of Psychological Sciences / Michael E. Young / Although risky decision-making tasks present some a priori risk (i.e., base-rate), decision makers often have an opportunity to modify this level of risk through their behaviors. Broadly speaking, risk can be modified by assigning additional resources to an ongoing task or by engaging in specific risk-mitigation strategies before or after the risky decision is made. The modification of risk requires ongoing awareness of task demands, resource constraints, and risk-mitigation strategies that can be used to adapt behavior over time. This thesis explores risk modification that occurs during difficult tasks. Difficult tasks hold greater risks because they fall at the edge of the decision maker’s abilities and are likely to require a greater number of resources to overcome. As resources are engaged they become unavailable for other tasks or strategies to cope with changing task demands. I studied how individuals monitor risks and develop risk mitigation strategies using a videogame task designed to mirror contingencies that would be encountered in the real world. Results from two experiments that involve this task suggest that decision-makers adequately monitor and develop active strategies for dealing with risks. These strategies change over time and vary as a function of task difficulty and experience.