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Scalable and robust compute capacity multiplexing in virtualized datacentersKesavan, Mukil 27 August 2014 (has links)
Multi-tenant cloud computing datacenters run diverse workloads, inside virtual machines (VMs), with time varying resource demands. Compute capacity multiplexing systems dynamically manage the placement of VMs on physical machines to ensure that their resource demands are always met while simultaneously optimizing on the total datacenter compute capacity being used. In essence, they give the cloud its fundamental property of being able to dynamically expand and contract resources required on-demand.
At large scale datacenters though there are two practical realities that designers of compute capacity multiplexing systems need to deal with: (a) maintaining low operational overhead given variable cost of performing management operations necessary to allocate and multiplex resources, and (b) the prevalence of a large number and wide variety of faults in hardware, software and due to human error, that impair multiplexing efficiency. In this thesis we propound the notion that explicitly designing the methods and abstractions used in capacity multiplexing systems for this reality is critical to better achieve administrator and customer goals at large scales.
To this end the thesis makes the following contributions: (i) CCM - a hierarchically organized compute capacity multiplexer that demonstrates that simple designs can be highly effective at multiplexing capacity with low overheads at large scales compared to complex alternatives, (ii) Xerxes - a distributed load generation framework for flexibly and reliably benchmarking compute capacity allocation and multiplexing systems, (iii) A speculative virtualized infrastructure management stack that dynamically replicates management operations on virtualized entities, and a compute capacity multiplexer for this environment, that together provide fault-scalable management performance for a broad class of commonly occurring faults in large scale datacenters.
Our systems have been implemented in an industry-strength cloud infrastructure built on top of the VMware vSphere virtualization platform and the popular open source OpenStack cloud computing platform running ESXi and Xen hypervisors, respectively. Our experiments have been conducted in a 700 server datacenter using the Xerxes benchmark replaying trace data from production clusters, simulating parameterized scenarios like flash crowds, and also using a suite of representative cloud applications. Results from these scenarios demonstrate the effectiveness of our design techniques in real-life large scale environments.
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Cattle grazing in the national parks| Historical developmentPinto, Robin Lothrop 28 August 2014 (has links)
<p> This dissertation traces the history of cattle grazing at Saguaro NP, Organ Pipe Cactus NM and Fort Bowie NHS in southern Arizona. This collection of studies examines the factors affecting that use, the ranchers who made their living from the landscape, and the federal land managers responsible for sustaining the natural and cultural resources. </p><p> A dominant industry on arid public lands since the Civil War, grazing was altered by a variety of influences: environmental and human-derived. Ranching communities developed from homesteading settlements. Success was determined by climate, topography, and natural resources; social and cultural pressures; economic events and political legislation; and later federal regulations and decisions. </p><p> The first agency to oversee grazing, USFS was under constant pressure to maximize short-term human benefits. The NPS Organic Act of 1916 mandated conservation of natural resources "by such means as will leave them unimpaired for future generations" and yet approved cattle grazing, an extractive use, under USFS management. Park managers were frustrated by grazing practices not under their control. Parks were at a cultural and social disadvantage. Residents and politicians often expressed displeasure at park reservations; communities feared that parks would interfere with local industries. </p><p> Park employees supervised visitors and developed recreation infrastructure; they came with little experience to manage livestock. Lack of funding for research, limited manpower, and political and administrative interference allowed cattle grazing to continue unregulated for decades altering vegetation and enhancing erosion. In the 1960s, changing values from the environmental movement, the waning power of the livestock industry, and the rise of activist scientists impelled NPS to act. Without monitoring data, NPS turned to legal opinions to terminate grazing. </p><p> Now grazing is regulated and carefully monitored. NPS is mandated to incorporate research results into management decisions. Older grazing permits are being retired, but land acquisitions for park additions add new management challenges. Purchasing permits offers a new but financially limited opportunity to protect sensitive lands. Grazing has ended at all three parks, yet ecological changes and historic structures remain. As cultural and administrative legacies, those remnants offer opportunities to interpret a significant regional tradition and an untold controversy.</p>
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In-season Drought Monitoring| Testing Instrumentation and Developing Methods of Measurement AnalysisRaper, Tyson B. 28 August 2014 (has links)
<p> Soil moisture sensor use in crop production systems has the potential to give inference on plant water status for the purpose of irrigation scheduling and site-drought characterization. These processed measurements could serve as the framework on which to compile trial results across locations, thereby more accurately defining varietal yield response to drought. Still, the ability to characterize drought within a given field or initiate irrigations from these data hinge upon the ability of the instrument to characterize soil moisture at the sampled point and extrapolate that information across the landscape and time. Therefore, the objectives of this research were to: (1) test the response of the Watermark 200SS (Irrometer Company, Inc., Riverside, CA) and Decagon 10HS (Decagon Devices, Inc., Pullman, WA) to changes in water content of three dissimilar soils representing common soils in row-crop production under variable environmental conditions; (2) develop a soil moisture-based index to quantify drought stress in dryland cotton cultivar trials; and (3) determine if a limited number of soil moisture sensors deployed into a dryland cultivar trial could accurately characterize the VWC at a given point within the field and if this measurement could be extrapolated out to the field scale from the very small sphere of influence characterizing the utilized soil moisture sensors. During the 2012 and 2013 growing seasons soil moisture sensors were deployed into over 14 cotton cultivar trials across the U.S. Cotton Belt and into a water-input controlled container study. Tested sensors' inability to accurately predict container VWC emphasized the relatively small quantity of soil on which these sensors rely and the variability in soil moisture within a very limited volume. Results from the drought-index studies suggested both the Accumulated Soil Moisture Stress Index (ASMSI) and the relative reduction in evapotranspiration (1-(ET<sub>c adj</sub>/ET<sub>c</sub>)) appear to have potential in characterizing the amount of stress experienced within dryland cultivar trials. Analysis of spatial and temporal stability suggested trends between sensors were consistent, but absolute node readings varied. Optimism concerning the potential of these measurements/approaches for increasing water use efficiency is coupled with a call for more arbitrary, universal methods of measurement analysis.</p>
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GENDER AND DECISION-MAKING IN NATURAL RESOURCE CO-MANAGEMENT IN YUKON TERRITORY2014 May 1900 (has links)
Across the Canadian North, resource co-management has become a central institution for the management of natural resources. An inventory of co-management boards in Canada’s northern territories, conducted in 2012, identified more than 30 different boards, with responsibilities ranging from wildlife, water, lands and non-renewable natural resources (Natcher 2013). While operating along a continuum of institutional authority, co-management has been heralded by many as an effective means to engage resource users and government managers in a collaborative and more equitable approach to environmental decision-making. Although a considerable amount of multi-disciplinary research has examined the various social and political dimensions that influence the effectiveness of resource co-management, little has been done to understand how gender might affect collaboration and decision-making within this resource regime. This gap in understanding is particularly evident in the northern Canadian context, where women make up 16% of all current co-management board members.
With the intention to address this analytical void, this study set out to examine the ways in which a gender imbalance influences board decision-making and the experiences of those involved in co-management boards that have been established in the Yukon Territory. It focused in particular on women within these institutions, while also acknowledging broader gender roles that involve both men and women. Written surveys and semi-structured interviews demonstrated that the representation of women within these institutions was important to establishing a holistic decision-making process and positive institutional culture that facilitated effective decision-making. The presence of women on these boards also influenced the scope and efficacy of decision outcomes. Participants found that though opportunities to participate in decision-making existed, there were still barriers preventing board members from acting on these opportunities. These barriers were often experienced by men and women in different ways. Implicit within these findings are the gendered roles and characteristics that shape the activities and expectations of those involved with co-management institutions. Gendered roles in the community and on the land were particularly relevant to these boards. This research contributes to a more informed understanding of a critical, yet unexplored, aspect of the social and political context of co-management, with practical implications for how effective decision-making is interpreted and implemented by these boards.
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Exploring the Sustainability of Control of Qinhuai River: A case study in Nanjing, Jiangsu, ChinaHu, Jingwei January 2014 (has links)
Qinhuai river in Nanjing, China, has suffered pollution since the late 1970s. To solve the problem, Nanjing Municipality conducted two river control projects. The first one in 2002 ended up a failure, and the second one in 2012 also faced various hinders. The aim of the thesis is to examine the sustainability of the river control launched in 2012, and to contribute with some suggestions for improvement. In this thesis, the author used methods of interview and literature review to gain the empirical data of the river control, used method of stakeholder analysis to analyze the data with the lens of sustainable development, Integrated Water Resource Management (IWRM) and externalities. After the analysis, the river control is considered unsustainable. The conclusion is that the pollution mainly originates from wasted domestic water. And the river control launched in 2012 is not sustainable as it lacks long-term perspective, social participation, gender awareness and solutions to mitigate the externalities. The emphasis is that, as the enabler, regulator and provision offer, Nanjing Municipality needs to raise social participation and internalize the environmental externalities to reach sustainable management of the Qinhuai river.
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Coast redwood fire history and land use in the Santa Cruz Mountains, CaliforniaJones, Gregory A. 11 November 2014 (has links)
<p> Physical evidence of past fires, left in the form of cambial scars, suggests that low and moderate intensity fires have burned periodically for centuries in the coast redwood (<i>Sequoia sempervirens</i>) forest in California's central coast bioregion. These fires may have played an important role in shaping stand age structure and composition. Nonetheless, the ecological role of fire in shaping successional processes in the redwood ecosystem is not well understood. The extent to which both aboriginal and more recent burning practices have affected the central coast landscape is also uncertain. Standard dendrochronology techniques were used to reconstruct and analyze the fire history of the coast redwood forest in the Santa Cruz Mountains based on the fire scar record. Three hundred and seventy-three fire scars were identified in 70 cross-sections that were removed from redwood stumps, downed logs, and trees in select locations between Davenport and Año Nuevo, California. The earliest recorded fire occurred in 1352 and the most recent in 2009. The grand mean fire return interval (FRI) for single trees (point) was 60.6 years, and the median FRI was 40.1 years. Fire scars were found most frequently in the dormant and latewood portions of the annual growth rings, signifying that fires tended to occur in the late summer and fall. A high degree of variability in the data set suggests that cultural burning practices occurred on fluctuating temporal and spatial scales.</p>
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Nuwuvi (Southern Paiute) Ecological Knowledge of Pi?on-Juniper Woodlands| Implications for Conservation and Sustainable Resource Use in Two Southern Nevada Protected AreasLefler, Brian John 18 November 2014 (has links)
<p> Nuwuvi (Southern Paiute) have inhabited the southern Great Basin for thousands of years, and consider <i>Nuvagantu</i> (where snow sits) in the Spring Mountains landscape to be the locus of their creation as a people. Their ancestral territory spans parts of Nevada, Utah, Arizona, and California. My research identifies and describes the heterogeneous character of Nuwuvi ecological knowledge (NEK) of piñon-juniper woodland ecosystems within two federal protected areas (PAs) in southeastern Nevada, the Spring Mountains National Recreation Area (SMNRA) and the Desert National Wildlife Refuge (DNWR), as remembered and practiced to varying degrees by 22 select Nuwuvi knowledge holders. I focus my investigation on four primary aspects of NEK. First, drawing from data obtained through ethnoecological research, I discuss how Nuwuvi ecological knowledge evolved through protracted observation and learning from past resource depletions, and adapted to various environmental and socio-economic drivers of change induced since Euro-American incursion. Second, I argue that Nuwuvi management practices operate largely within a framework of non-equilibrium ecology, marked by low to intermediate disturbances and guided by Nuwuvi conceptions of environmental health and balance. These practices favor landscape heterogeneity and patchiness, and engender ecosystem renewal, expanded ecotones, and increased biodiversity. I then consider the third and fourth aspects of NEK as two case studies that consider NEK at the individual, species, population, habitat, and landscape scales. These case studies operationalize NEK as a relevant body of knowledge and techniques conducive to collaborative resource stewardship initiatives with federal land management agency partners. In the first case study I suggest that the Great Basin piñon pines are Nuwuvi cultural keystone species (CKS), evaluating their central importance to Nuwuvi according to several criteria including number of uses, role in ritual and story, and uniqueness relative to other species. In the second case study I contend that local social institutions regulated Nuwuvi resource use in the past and in some cases continued to do so at the time of study. These local social institutions included a system of resource extraction and habitat entrance taboos that may have mitigated impacts and supported sustainable resource use and conservation. The implications of this research are that Nuwuvi ecological knowledge, disturbance-based adaptive management practices, and resource and habitat taboos are relevant to contemporary land management concerns in piñon-juniper woodlands, offering complementary approaches to adaptive management as practiced in the SMNRA and the DNWR despite divergent epistemological foundations. My research contributed to the Nuwuvi Knowledge-to-Action Project, an applied government-to-government consultation, collaborative resource stewardship, and cultural revitalization project facilitated by The Mountain Institute among seven Nuwuvi Nations, the U.S. Forest Service, and the U.S. Fish and Wildlife Service.</p>
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Supplementing soybean meal with Camelina (Camelina sativa) in tilapia diets and optimizing commercial tilapia diets for use in intensive systems in the Western region of the United StatesRamotar-John, Badule Pamila 21 October 2014 (has links)
<p> The feed production cost in tilapia diets is driven by the prices of its ingredients such as fishmeal (FM) and soybean meal (SBM). Fishmeal and soymeal combined with other ingredients provides fish with the nutrients required for growth and sustaining life. Soybean meal is used as an alternative to fishmeal, but prices for this traditional ingredient have increased significantly in recent years as a result of high market demand from other industries. Consequently, there has been an increase interest by tilapia nutritionists and feed manufacturers to find less expensive, alternative feedstuffs for use in tilapia diets. </p><p> Camelina <i>(Camelina sativa)</i> is an oil seed crop grown in higher latitudes especially along the US - Canada border, northern China and northern Europe. Camelina after removal of most of the edible oil has been proposed as a fish feed ingredient. </p><p> A sixty-day feeding trial was conducted and diets were formulated to contain various levels of camelina inclusion (0, 5, 10, 15, 20 and 25%) for the “camelina meal” while the “camelina oil” was formulated to contain one level (4.7%) of oil and was divided as “raw” and 4.7 “wash”. The results indicated that that fishes fed diets containing camelina ingredients had growth performance and feed utilization results that were similar to fish fed the commercial diet (P>0.05). There were significant differences (P<0.05) for body organ indices and body composition. The 15% camelina meal diet was the lowest cost experimental diet per kilogram gain and therefore, this alternative ingredient might be a potential replacement for soymeal in a more cost effective feed formulation. </p><p> The fatty acid composition of tilapia fillets was also analyzed at the end of the feeding trial. The inclusion of camelina meal and oil in tilapia diets resulted in significant increases in the Omega-3/Omega-6 ratio in fillets when compared to the control. The 15% camelina meal provided the best results of the experimental diets yielding significantly higher polyunsaturated fatty acid (PUFA) and lower saturated fatty aid (SFA) than the control diet. </p><p> On a commercial scale, tilapia commercial feeds differ in both formulated nutrient levels and ingredient composition. In intensive system culture, natural food is limited making it important that all nutrients are supplied through a complete pelleted diet. An advantage to feeding a pelleted diet is that the pellet-type feed enables the farmers, feed formulators and manufactures to design a diet that provides an optimal nutritional mix for tilapia. </p><p> Precise levels in the protein and lipid percentages of tilapia diets can reduce feed costs and also reduce the amount of underutilized protein and lipids stored as fat in tilapia. Feed comprises of over 60% of the variable cost in the intensive aquaculture operation; if feed prices were to increase, it would be a substantial amount for tilapia producers to absorb. Therefore an improved diet formulation designed for tilapia can increase profitability. </p><p> Results indicated that the experimental diets (28% Crude Protein (CP)-Amino Acid (AA), 28% CP and 40% CP) performed similar to the control diet (32% CP) as it relates to fish growth. The experiment conducted on a commercial scale at an operating farm found that feeding tilapia the lowest protein level diets (28% CP) resulted in higher biomass gain per raceway, biomass gain per fish and significantly higher protein efficiency ratio (PER) when compared to the control diet (32% CP). The 28% CP diet also had the second best FCR value and most importantly higher returns based on its FCR when compared to the control diet (32% CP).</p>
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Valuing water| A normative analysis of prior appropriationElbot, Morgan Bradfield 23 October 2014 (has links)
<p> This thesis aims to provide a normative evaluation of the Western U.S. water law of prior appropriation through a contextual analysis of water value pluralism. The first chapter begins with a preliminary account of the major justificatory arguments made in defense of prior appropriation, followed by two critiques that undermine some proposed advantages of the water policy. The purpose of this analysis is to elucidate the normative claims that underlie many of the arguments within this debate but which fail to be made explicit. It becomes clear that these normative claims assume a utilitarian criterion for resource distribution, according to which water is primarily viewed as an economic good with a monetary value. The second chapter challenges the legitimacy of this assumption by introducing non-monetary water values, with attention to the particular social and cultural contexts in which they emerge. Through a review of four economic proxies, these non-monetary water values are shown to be incommensurable with monetary valuations. Finally, the third chapter offers a theoretical framework for the incorporation of non-monetary water values into resource distribution decisions. From this normative analysis, it is concluded that a necessary condition for achieving just resource distribution decisions is for prior appropriation to incorporate value pluralism by recognizing the legitimacy of non-monetary water values.</p>
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Radio Resource Management in a Heterogeneous Wireless Access MediumMuhammad, Muhammad Ismail 08 July 2013 (has links)
In recent years, there has been a rapid evolution and deployment of wireless networks. In populated areas, high-rate data access is enabled anywhere and anytime with the pervasive wireless infrastructure such as the fourth-generation (4G) cellular systems, IEEE 802.11-based wireless local area networks (WLANs), and IEEE 802.16-based wireless metropolitan area networks (WMANs). In such a heterogeneous wireless access medium, multi-radio devices become a trend for users to conveniently explore various services offered by different wireless systems. This thesis presents radio resource management mechanisms, for bandwidth allocation, call admission control (CAC), and mobile terminal (MT) energy management, that can efficiently exploit the available resources in the heterogeneous wireless medium and enhance the user perceived quality-of-service (QoS).
Almost all existing studies on heterogeneous networking are limited to the traditional centralized infrastructure, which is inflexible in dealing with practical scenarios, especially when different networks are operated by different service providers. In addition, in most current wireless networks, mobile users are simply viewed as service recipients in network operation, with passive transceivers completely or partially under the control of base stations or access points. In this thesis, we present efficient decentralized bandwidth allocation and CAC mechanisms that can support single-network and multi-homing calls. The decentralized architecture gives an active role to the MT in the resource management operation. Specifically, an MT with single-network call can select the best wireless network available at its location, while an MT with multi-homing call can determine a required bandwidth share from each network to satisfy its total required bandwidth. The proposed mechanisms rely on cooperative networking and offer a desirable flexibility between performance measures (in terms of the allocated bandwidth per call and the call blocking probability), and between the performance and the implementation complexity.
With the increasing gap between the MT demand for energy and the offered battery capacity, service degradation is expected if the MT cannot efficiently manage its energy consumption. Specifically, for an uplink multi-homing video transmission, the existing studies do not guarantee that the MT available energy can support the entire call, given the battery energy limitation. In addition, the energy management mechanism should take account of video packet characteristics, in terms of packet distortion impact, delay deadline, and precedence constraint, and employ the available resources in the heterogeneous wireless medium. In this thesis, we present MT energy management mechanisms that can support a target call duration, with a video quality subject to the MT battery energy limitation. In addition, we present a statistical guarantee framework that can support a consistent video quality for the target call duration with minimum power consumption.
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