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2008

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Faster Optimal State-Space Search With Graph Decomposition And Reduced Expansion, Yixin Chen Jan 2008

Faster Optimal State-Space Search With Graph Decomposition And Reduced Expansion, Yixin Chen

All Computer Science and Engineering Research

Traditional AI search methods, such as BFS, DFS, and A*, look for a path from a starting state to the goal in a state space most typically modelled as a directed graph. Prohibitively large sizes of the state space graphs make optimal search difficult. A key observation, as manifested by the SAS+ formalism for planning, is that most commonly a state-space graph is well structured as the Cartesian product of several small subgraphs. This paper proposes novel search algorithms that exploit such structure. The results reveal that standard search algorithms may explore many redundant paths. Our algorithms provide an automatic …

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Multi-Application Deployment In Integrated Sensing Systems Based On Quality Of Monitoring, Sangeeta Bhattacharya, Abusayeed Saifullah, Chenyang Lu, Gruia-Catalin Roman Jan 2008

Multi-Application Deployment In Integrated Sensing Systems Based On Quality Of Monitoring, Sangeeta Bhattacharya, Abusayeed Saifullah, Chenyang Lu, Gruia-Catalin Roman

All Computer Science and Engineering Research

No abstract provided.

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Flexible Service Provisioning For Heterogeneous Sensor Networks, Chien-Liang Fok, Gruia-Catalin Roman, Chenyang Lu Jan 2008

Flexible Service Provisioning For Heterogeneous Sensor Networks, Chien-Liang Fok, Gruia-Catalin Roman, Chenyang Lu

All Computer Science and Engineering Research

This paper presents Servilla, a highly flexible service provisioning framework for heterogeneous wireless sensor networks. Its service-oriented programming model and middleware enable developers to construct platform-independent applications over a dynamic set of devices with diverse computational resources and sensors. A salient feature of Servilla is its support for dynamic discovery and binding to local and remote services, which enables flexible and energy-efficient in-network collaboration among heterogeneous devices. Furthermore, Servilla provides a modular middleware architecture that can be easily tailored for devices with a wide range of resources, allowing even resource-limited devices to provide services and leverage resource-rich devices for in-network …

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Animal Microrna Target Prediction By Incorporating Diverse Sequence-Specific Determinants, Yun Zheng, Weixiong Zhang Jan 2008

Animal Microrna Target Prediction By Incorporating Diverse Sequence-Specific Determinants, Yun Zheng, Weixiong Zhang

All Computer Science and Engineering Research

More recent evidence has shown that access of animal microRNAs (miRNAs) to their complementary sites in target mRNAs is determined by more sequence-specific determinants than the seed regions in the 5' end of miRNAs. Although these factors have been shown to be related to the repressive power of miRNAs and used, in separate programs, to predict the efficacy of miRNA complementary sites, it remains unclear whether these factors can help to improve miRNA target prediction. We develop a new miRNA target prediction algorithm, called Hitsensor, by incorporating more sequence-specific features that determine complementarities between miRNAs and their targets, in addition …

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Software And Hardware Acceleration Of The Genomic Motif Finding Tool Phylonet, Justin Brown Jan 2008

Software And Hardware Acceleration Of The Genomic Motif Finding Tool Phylonet, Justin Brown

All Computer Science and Engineering Research

No abstract provided.

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Reliable Data Collection From Mobile Users For Real-Time Clinical Monitoring, Octav Chipara, Christopher Brooks, Sangeeta Bhattacharya, Chenyang Lu Jan 2008

Reliable Data Collection From Mobile Users For Real-Time Clinical Monitoring, Octav Chipara, Christopher Brooks, Sangeeta Bhattacharya, Chenyang Lu

All Computer Science and Engineering Research

Real-time patient monitoring is critical to early detection of clinical patient deterioration in general hospital wards. A key challenge in such applications is to reliably deliver sensor data from mobile patients. We present an empirical analysis on the reliability of data collection from wireless pulse oximeters attached to users. We observe that most packet loss occur from mobile users to their first-hop relays. Based on this insight we developed the Dynamic Relay Association Protocol (DRAP), a simple and effective mechanism for dynamically discovering the right relays for wireless sensors attached to mobile users. DRAP enables highly reliable data collection from …

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A Practical Schedulability Analysis For Generalized Sporadic Tasks In Distributed Real-Time Systems, Yuanfang Zhang, Donald K. Krecker, Christopher Gill, Chenyang Lu, Guatam H. Thakar Jan 2008

A Practical Schedulability Analysis For Generalized Sporadic Tasks In Distributed Real-Time Systems, Yuanfang Zhang, Donald K. Krecker, Christopher Gill, Chenyang Lu, Guatam H. Thakar

All Computer Science and Engineering Research

Existing off-line schedulability analysis for real-time systems can only handle periodic or sporadic tasks with known minimum inter-arrival times. Modeling sporadic tasks with fixed minimum inter-arrival times is a poor approximation for systems in which tasks arrive in bursts, but have longer intervals between the bursts. In such cases, schedulability analysis based on the existing sporadic task model is pessimistic and seriously overestimates the task's time demand. In this paper, we propose a generalized sporadic task model that characterizes arrival times more precisely than the traditional sporadic task model, and we develop a corresponding schedulability analysis that computes tighter bounds …

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Reconfigurable Real-Time Middleware For Distributed Cyber-Physical Systems With Aperiodic Events, Yuanfang Zhang, Christopher Gill, Chenyang Lu Jan 2008

Reconfigurable Real-Time Middleware For Distributed Cyber-Physical Systems With Aperiodic Events, Yuanfang Zhang, Christopher Gill, Chenyang Lu

All Computer Science and Engineering Research

Different distributed cyber-physical systems must handle aperiodic and periodic events with diverse requirements. While existing real-time middleware such as Real-Time CORBA has shown promise as a platform for distributed systems with time constraints, it lacks flexible configuration mechanisms needed to manage end-to-end timing easily for a wide range of different cyber-physical systems with both aperiodic and periodic events. The primary contribution of this work is the design, implementation and performance evaluation of the first configurable component middleware services for admission control and load balancing of aperiodic and periodic event handling in distributed cyber-physical systems. Empirical results demonstrate the need for, …

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Real-Time Performance And Middleware On Multicore Linux Platforms, Yuanfang Zhang, Christopher Gill, Chenyang Lu Jan 2008

Real-Time Performance And Middleware On Multicore Linux Platforms, Yuanfang Zhang, Christopher Gill, Chenyang Lu

All Computer Science and Engineering Research

An increasing number of distributed real-time applications are running on multicore platforms. However, existing real-time middleware (e.g., Real-Time CORBA) lacks support for scheduling soft real-time tasks on multicore platforms while guaranteeing their time constraints will be satisfied. This paper makes three contributions to the state of the art in real-time system software for multicore platforms. First, it offers what is to our knowledge the first experimental analysis of real-time performance for vanilla Linux primitives on multicore platforms. Second, it presents MC-ORB, the first real-time object request broker (ORB), designed to exploit the features of multicore platforms, with admission control and …

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Deciding Joinability Modulo Ground Equations In Operational Type Theory, Adam Petcher, Aaron Stump Jan 2008

Deciding Joinability Modulo Ground Equations In Operational Type Theory, Adam Petcher, Aaron Stump

All Computer Science and Engineering Research

Operational Type Theory (OpTT) can be used to construct and check proofs related to programs, but the development of these proofs can be somewhat tedious. An algorithm is presented that can be used to automatically generate proofs of equality in OpTT. The algorithm takes as input a set of ground equations and two terms that should be tested for joinability modulo the supplied ground equations. The algorithm will equate the terms if and only if there exists an OpTT proof that can equate the two terms using only the proof rules related to evaluation under the operational semantics, symmetry, transitivity, …

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Local Neighborhoods For Shape Classification And Normal Estimation, Cindy Grimm, William Smart Jan 2008

Local Neighborhoods For Shape Classification And Normal Estimation, Cindy Grimm, William Smart

All Computer Science and Engineering Research

We introduce the concept of local neighborhoods, a generalization of the one-ring on a mesh to unlabeled 3D data points arising from sampling a 2D surface embedded in 3D. The local neighborhood supports both local shape classification and robust normal estimation. In particular, local neighborhoods out-perform traditional approaches in unevenly sampled, curved regions. We show that the local neighborhood can be used in place of a full mesh structure for applications such as smoothing, moving least-squares reconstruction, and parameterization. Longer version of paper submitted to CAGD

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Scheduling For Reliable Execution In Autonomic Systems, Terry Tidwell, Robert Glaubius, Christopher Gill, William D. Smart Jan 2008

Scheduling For Reliable Execution In Autonomic Systems, Terry Tidwell, Robert Glaubius, Christopher Gill, William D. Smart

All Computer Science and Engineering Research

Scheduling the execution of multiple concurrent tasks on shared resources such as CPUs and network links is essential to ensuring the reliable operation of many autonomic systems. Well known techniques such as rate-monotonic scheduling can offer rigorous timing and preemption guarantees, but only under assumptions (i.e., a fixed set of tasks with well-known execution times and invocation rates) that do not hold in many autonomic systems. New hierarchical scheduling techniques are better suited to enforce the more flexible execution constraints and enforcement mechanisms that are required for autonomic systems, but a rigorous foundation for verifying and enforcing concurrency and timing …

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Financial Monte Carlo Simulation On Architecturally Diverse Systems, Naveen Singla, Michael Hall, Berkley Shands, Roger D. Chamberlain Jan 2008

Financial Monte Carlo Simulation On Architecturally Diverse Systems, Naveen Singla, Michael Hall, Berkley Shands, Roger D. Chamberlain

All Computer Science and Engineering Research

Computational finance relies heavily on the use of Monte Carlo simulation techniques. However, Monte Carlo simulation is computationally very demanding. We demonstrate the use of architecturally diverse systems to accelerate the performance of these simulations, exploiting both graphics processing units and field-programmable gate arrays. Performance results include a speedup of 74× relative to an 8 core multiprocessor system (180× relative to a single processor core).

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Practical Schedulability Analysis For Generalized Sporadic Tasks In Distributed Real-Time Systems, Yuanfang Zhang, Donald K. Krecker, Christopher Gill, Chenyang Lu, Guatam H. Thaker Jan 2008

Practical Schedulability Analysis For Generalized Sporadic Tasks In Distributed Real-Time Systems, Yuanfang Zhang, Donald K. Krecker, Christopher Gill, Chenyang Lu, Guatam H. Thaker

All Computer Science and Engineering Research

Existing off-line schedulability analysis for real-time systems can only handle periodic or sporadic tasks with known minimum inter-arrival times. Modeling sporadic tasks with fixed minimum inter-arrival times is a poor approximation for systems in which tasks arrive in bursts, but have longer intervals between the bursts. In such cases, schedulability analysis based on the existing sporadic task model is pessimistic and seriously overestimates the task's time demand. In this paper, we propose a generalized sporadic task model that characterizes arrival times more precisely than the traditional sporadic task model, and we develop a corresponding schedulability analysis that computes tighter bounds …

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Partial Program Admission By Path Enumeration, Michael Wilson, Ron Cytron, Jon Turner Jan 2008

Partial Program Admission By Path Enumeration, Michael Wilson, Ron Cytron, Jon Turner

All Computer Science and Engineering Research

Real-time systems on non-preemptive platforms require a means of bounding the execution time of programs for admission purposes. Worst-Case Execution Time (WCET) is most commonly used to bound program execution time. While bounding a program's WCET statically is possible, computing its true WCET is difficult without significant semantic knowledge. We present an algorithm for partial program admission, suited for non-preemptive platforms, using dynamic programming to perform explicit enumeration of program paths. Paths - possible or not - are bounded by the available execution time and admitted on a path-by-path basis without requiring semantic knowledge of the program beyond its Control …

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Transcriptome Analysis Of Alzheimer's Disease Identifies Links To Cardiovascular Disease, Monika Ray, Jianhua Ruan, Weixiong Zhang Jan 2008

Transcriptome Analysis Of Alzheimer's Disease Identifies Links To Cardiovascular Disease, Monika Ray, Jianhua Ruan, Weixiong Zhang

All Computer Science and Engineering Research

No abstract provided.

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A Holistic Approach To Decentralized Structural Damage Localization Using Wireless Sensor Networks, Gregory Hackmann, Fei Sun, Nestor Castaneda, Chenyang Lu, Shirley Dyke Jan 2008

A Holistic Approach To Decentralized Structural Damage Localization Using Wireless Sensor Networks, Gregory Hackmann, Fei Sun, Nestor Castaneda, Chenyang Lu, Shirley Dyke

All Computer Science and Engineering Research

Wireless sensor networks (WSNs) have become an increasingly compelling platform for Structural Health Monitoring (SHM) applications, since they can be installed relatively inexpensively onto existing infrastructure. Existing approaches to SHM in WSNs typically address computing system issues or structural engineering techniques, but not both in conjunction. In this paper, we propose a holistic approach to SHM that integrates a decentralized computing architecture with the Damage Localization Assurance Criterion algorithm. In contrast to centralized approaches that require transporting large amounts of sensor data to a base station, our system pushes the execution of portions of the damage localization algorithm onto the …

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Deconstructing The Politics Of Culture Jamming, Jana Seidl Jan 2008

Deconstructing The Politics Of Culture Jamming, Jana Seidl

Harriet L Wilkes Honors College Theses 2003 - 2009

Culture Jammers, an activist guerilla-like movement, entered the global scene in the 1990s and, through public performances, attempt to draw attention to their claim that the US economic structure is facing a fundamental need to shift away from a consumer-oriented capitalist economy. As an alternative, the activists propose--True Cost economics, a model that would include the costs of negative production and consumption externalities in the pricing of commodities. In this paper, I focus on culture jammers' critique of neoclassical economics, more specifically, the clash of the--new paradigm (True Cost economics) and the old paradigm (neoclassical economics). In evaluating whether True …

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Logrolling In The Supreme Court, Echo Marie. Keif Jan 2008

Logrolling In The Supreme Court, Echo Marie. Keif

Harriet L Wilkes Honors College Theses 2003 - 2009

While studies have considered the presence and impact of logrolling (vote trading) on legislative actors, little work has questioned the possibility of judicial logrolling among Supreme Court Justices. Supreme Court Justices are usually assumed to be free from constituencies and political party pressures. This assumption is derived from life-long appointments that do not require the endorsement of reelection. However, public choice would predict the presence of logrolling in cases where intense differences in preferences exist among justices. We only expect to see logrolling when vote trading has the potential to change voting outcomes. Thus, to study the probability of logrolling …

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Determination Of The Acid Dissociation Constant Of Cytochrome B5 Reductase, Samantha. Chong Jan 2008

Determination Of The Acid Dissociation Constant Of Cytochrome B5 Reductase, Samantha. Chong

Harriet L Wilkes Honors College Theses 2003 - 2009

Most living organisms transduce electron transport chains in order to obtain energy. Flavin adenine dinucleotide (FAD) is a common electron transfer cofactor found in electron transport proteins referred to as flavoproteins. In this study, the different ionization and oxidation states of this cofactor found in cytochrome b5 reductase were identified spectroscopically and quantified as a function of solution potential and pH. The large data sets obtained from these experiments were analyzed and the acid dissociation constant for reduced cytochrome b5 reductase was determined.

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Metaphors And Modalities: Meditations On Bobbitt’S Theory Of The Constitution, Ian C. Bartrum Jan 2008

Metaphors And Modalities: Meditations On Bobbitt’S Theory Of The Constitution, Ian C. Bartrum

Scholarly Works

This article builds on Philip Bobbitt's remarkable work in constitutional theory, which posits a practice-based constitution based in six accepted "modalities" of argument. I attempt to supplement Bobbitt's theory - which has a static and exclusive quality to it - with an account of interpretive evolution based in Max Black's interaction theory of metaphors. I suggest that we can (and do) create constitutional metaphors by deliberately overlapping Bobbitt's modalities of argument, and that through these creative acts we can grow the practice of American constitutionalism. I then present case studies of this metaphoric process at work in three fields of …

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No Law Respecting The Practice Of Religion, Leslie C. Griffin Jan 2008

No Law Respecting The Practice Of Religion, Leslie C. Griffin

Scholarly Works

No abstract provided.

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Quantifying Twentieth Century Glacier Change In The Sierra Nevada, California, Hassan J. Basagic Jan 2008

Quantifying Twentieth Century Glacier Change In The Sierra Nevada, California, Hassan J. Basagic

Dissertations and Theses

Numerous small alpine glaciers occupy the high elevation regions of the central and southern Siena Nevada, California. These glaciers change size in response to variations in climate and are therefore important indicators of climate change. An inventory based on USGS topographic maps (l :24,000) revealed 1719 glaciers and perennial snow and ice features for a total area of 39.l5 ±7.52 km2. The number of 'true' glaciers, versus non-moving ice, is estimated to be 118, covering 15.87 ± 1.69 Km2. All glaciers were located on north to northeast aspects, at elevations >3000 m. Historical photographs, geologic evidence, …

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A Comparative Analysis Of Control Techniques For Formation Flying Spacecraft In An Earth/Moon-Sun L(2)-Centered Lissajous Orbit, Michael Farrar Jan 2008

A Comparative Analysis Of Control Techniques For Formation Flying Spacecraft In An Earth/Moon-Sun L(2)-Centered Lissajous Orbit, Michael Farrar

Master's Theses and Capstones

In this thesis, several control techniques are applied to an occulter satellite for a given formation flying mission. This research is in collaboration with the Flight Dynamics Analysis branch at the NASA Goddard Space Flight Center in Greenbelt, Maryland. The spacecraft is part of a leader-follower configuration which orbits about the Earth/Moon-Sun L2 libration point in a lissajous orbit. A controller is required to maintain a distance of 50,000 km between the occulter and the leader satellite in the radial direction with respect to the orbit. The occulter is allowed a tolerance range of 10 m within the "shadow" of …

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In-Vivo Delivery Of Dna Vaccines Using Metallo-Lipid Nanoparticles, Clarissa Sara Gomez Jan 2008

In-Vivo Delivery Of Dna Vaccines Using Metallo-Lipid Nanoparticles, Clarissa Sara Gomez

Open Access Theses & Dissertations

There has been a rapidly growing area of research in the design and synthesis of molecules that self-organize in water to form functional nanosystems and due to the high interest in the area metal ligand complexes were tested as drug delivery systems with a Leishmania vaccine. Herein, we present the design, synthesis and functional activity of Cu(II) and Zn(II) complexes that self-assemble in water to form spherical nanoscale structures that exhibit an affinity to bind DNA and deliver it into eukaryotic cells with a high percent efficiency in-vitro. In order to assess the effectiveness of these nanoparticles to deliver DNA …

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Allocating Emergency Response Vehicles To Cover Critical Infrastructures, Hao Lei Jan 2008

Allocating Emergency Response Vehicles To Cover Critical Infrastructures, Hao Lei

Open Access Theses & Dissertations

Optimal deployment of limited emergency response service units in a metropolitan area is of interests to public agencies. The limited emergency units not only have to respond to the demand for service by residents and businesses, but also cover Critical Infrastructures (CIs). This Thesis formulates an improved optimization model to allocate different types of Emergency Response Service (ERS) units among their candidate base stations. The allocation of units must ensure maximum coverage to CIs, subject to the capacities of the base stations, service standard in terms of time to reach the CIs, and the availability of the ERS units (when …

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Evaluating The Design And Management Of Community-Based Ecotourism Projects In Guatemala, Kassandra Lynne Miller Jan 2008

Evaluating The Design And Management Of Community-Based Ecotourism Projects In Guatemala, Kassandra Lynne Miller

Graduate Student Theses, Dissertations, & Professional Papers

Community-based ecotourism (CBE) has become the newest buzzword in development circles for its purported ability to provide alternative income generation for families and incentives to protect natural resources. Organizations such as the World Bank, World Wildlife Federation and USAID have supported these small-scale projects across the globe. However, there has been much debate over the efficacy of these projects. They are often developed, managed, and even owned by NGOs, not by local communities. Economic benefits resulting from the project are often directed toward one or two people in prominent positions within the community and not evenly distributed. The increase in …

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Exploring The Benefits Of An Outdoor Adventure Program For Improving Self-Esteem And Self-Efficacy And Reducing Problem Behaviors In Adolescent Girls, Kristen O'Shea Jan 2008

Exploring The Benefits Of An Outdoor Adventure Program For Improving Self-Esteem And Self-Efficacy And Reducing Problem Behaviors In Adolescent Girls, Kristen O'Shea

Graduate Student Theses, Dissertations, & Professional Papers

The study assessed change in self-efficacy, self-esteem, and problem behaviors from pre-treatment to post-treatment and at 6-month follow-up for adolescent girls enrolled in an outdoor adventure program. Family security and previous program experience were also considered. Participants included 62 girls (ages 10 - 18) from diverse ethnic and SES backgrounds (the majority were Euro American from middle class backgrounds). As expected, problem behaviors were negatively correlated with self-esteem throughout the trip; they were negatively correlated with self-efficacy at 6-month follow-up. Girls from "higher security" families reported significantly higher levels of self-esteem (p < .05) and fewer problem behaviors (p < .01) than girls from "lower security" families. A principal components analysis (PCA) was run to review test properties of one of the study measures, the modified General Self-Efficacy Scales. Limitations of the study, including low power and few statistically significant results, are discussed.

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Regularization Methods For Ill-Posed Poisson Imaging, N'Djekornom Dara Laobeul Jan 2008

Regularization Methods For Ill-Posed Poisson Imaging, N'Djekornom Dara Laobeul

Graduate Student Theses, Dissertations, & Professional Papers

The noise contained in images collected by a charge coupled device (CCD) camera is predominantly of Poisson type. This motivates the use of the negative logarithm of the Poisson likelihood in place of the ubiquitous least squares t-to-data. However, if the underlying mathematical model is assumed to have the form z = Au, where A is a linear, compact operator, the problem of minimizing the negative log-Poisson likelihood function is ill-posed, and hence some form of regularization is required. In this work, it involves solving a variational problem of the form u def = arg min u0 `(Au; z) + …

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Sage-Grouse And Energy Development: Integrating Science With Conservation Planning To Reduce Impacts, Kevin Eric Doherty Jan 2008

Sage-Grouse And Energy Development: Integrating Science With Conservation Planning To Reduce Impacts, Kevin Eric Doherty

Graduate Student Theses, Dissertations, & Professional Papers

Effective conservation planning in the face of rapid land use change requires knowledge of which habitats are selected at landscape scales, where those habitats are located, and how species ultimately respond to anthropogenic disturbance. I assessed sage-grouse (Centrocercus urophasianus) large scale habitat ecology and response to energy development in the winter and nesting seasons using radio-marked individuals in the Powder River Basin, Montana and Wyoming, USA. Landscape scale percent sagebrush (Artemisia spp.) cover at 4-km2 was the strongest predictor of use by sage-grouse in winter. After controlling for vegetation and topography, the addition the density of coal-bed natural gas wells …

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