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2014

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การควบคุมแบบโมเดลพรีดิกทีฟในการสกัดแบบเสริมฤทธิ์ของไอออนนีโอดิเมียมด้วยเยื่อแผ่นเหลวที่พยุงด้วยเส้นใยกลวง, วรรษมนต์ คอนเอม Jan 2014

การควบคุมแบบโมเดลพรีดิกทีฟในการสกัดแบบเสริมฤทธิ์ของไอออนนีโอดิเมียมด้วยเยื่อแผ่นเหลวที่พยุงด้วยเส้นใยกลวง, วรรษมนต์ คอนเอม

Chulalongkorn University Theses and Dissertations (Chula ETD)

งานวิจัยนี้นำเสนอการประยุกต์ใช้การควบคุมแบบโมเดลพรีดิกทีฟโดยเปรียบเทียบกับการควบคุมแบบพีไอดีสำหรับการควบคุมความเข้มข้นของไอออนนีโอดิเมียมในการสกัดแบบเสริมฤทธิ์ผ่านเยื่อแผ่นเหลวที่พยุงด้วยเส้นใยกลวงเพื่อควบคุมความเข้มข้นของไอออนนีโอดิเมียมขณะออกจากมอดูลของเส้นใยกลวงให้เข้าสู่ค่าเป้าหมาย โดยอาศัยค่าไอเอดีเป็นดัชนีชี้วัด ระบบที่ศึกษาคือ การสกัดไอออนนีโอดิเมียมในสารละลายกรดไนตริก สารสกัดคือ D2EHPA และ TOPO ผสมกันในอัตราส่วน 1:1 สารละลายนำกลับคือกรดซัลฟิวริกความเข้มข้น 1 โมลต่อลิตร รูปแบบการไหลผ่านมอดูลเส้นใยกลวงแบบไหลผ่านครั้งเดียวและสารละลายป้อนไหลสวนทางกับสารละลายนำกลับ และศึกษาสมรรถนะของตัวควบคุมทั้งสองแบบ เมื่อมีความคลาดเคลื่อนระหว่างแบบจำลองกับกระบวนการจริง ที่สภาวะปกติผลการจำลองแสดงให้เห็นว่า ตัวควบคุมทั้งแบบพีไอดีและโมเดลพรีดิกทีฟสามารถควบคุมความเข้มข้นของไอออนนีโอดิเมียมให้เข้าสู่ค่าเป้าหมายได้เร็วกว่ากระบวนการที่ไม่ใช้ตัวควบคุม โดยตัวควบคุมแบบโมเดลพรีดิกทีฟสามารถควบคุมความเข้มข้นของไอออนนีโอดิเมียมให้เข้าสู่ค่าเป้าหมายได้เร็วกว่าตัวควบคุมแบบพีไอดี และเมื่อแบบจำลองมีความคลาดเคลื่อนไปจากกระบวนการจริง ตัวควบคุมทั้งสองแบบสามารถควบคุมความเข้มข้นให้เข้าสู่ค่าเป้าหมายได้ โดยตัวควบคุมแบบโมเดลพรีดิกทีฟให้สมรรถนะที่ดีกว่าการควบคุมแบบพีไอดีทั้งกรณีที่แบบจำลองมีความถูกต้องและแบบจำลองมีความคลาดเคลื่อนไปจากกระบวนการจริง


การประยุกต์ใช้กระบวนการลำดับชั้นเชิงวิเคราะห์ในการเลือกทำเลที่ตั้งศูนย์กระจายสินค้า : กรณีศึกษาศูนย์กระจายสินค้าธุรกิจร้านสะดวกซื้อ, วราภรณ์ โลหิตปุระ Jan 2014

การประยุกต์ใช้กระบวนการลำดับชั้นเชิงวิเคราะห์ในการเลือกทำเลที่ตั้งศูนย์กระจายสินค้า : กรณีศึกษาศูนย์กระจายสินค้าธุรกิจร้านสะดวกซื้อ, วราภรณ์ โลหิตปุระ

Chulalongkorn University Theses and Dissertations (Chula ETD)

งานวิจัยนี้เป็นการประยุกต์ใช้กระบวนการลำดับชั้นเชิงวิเคราะห์ (Analytic Hierarchy Process) ในการกำหนดทำเลที่ตั้งศูนย์กระจายสินค้าแห่งใหม่เพื่อรองรับปริมาณสินค้าที่เพิ่มขึ้นในอีก 3 ปีข้างหน้า โดยมีกรณีศึกษาของงานวิจัย เป็นศูนย์กระจายสินค้าที่ดำเนินธุรกิจด้านการกระจายสินค้าให้กับร้านสะดวกซื้อของบริษัท และนอกจากนี้ยังมีวัตถุประสงค์เพื่อศึกษา และวิเคราะห์ปัจจัยเชิงปริมาณ และปัจจัยเชิงคุณภาพที่มีผลต่อการเลือกทำเลที่ตั้งศูนย์กระจายสินค้าของธุรกิจร้านสะดวกซื้อ กระบวนการลำดับชั้นเชิงวิเคราะห์เป็นกระบวนการสนับสนุนการตัดสินใจที่มีเหตุผลสามารถใช้ในการตัดสินใจ ที่เกี่ยวข้องกับปัจจัยทั้งเชิงปริมาณ และเชิงคุณภาพ อีกทั้งยังสามารถวัดความสอดคล้องของการตัดสินใจในแต่ละปัจจัย และนอกจากนี้งานวิจัยยังได้มีการวิเคราะห์ต้นทุนค่าขนส่งของทางเลือกของที่ตั้งที่พิจารณาประกอบการตัดสินใจร่วมด้วย งานวิจัยได้พิจารณาทางเลือกของที่ตั้งศูนย์กระจายสินค้าจำนวน 3 จังหวัด ได้แก่ จังหวัดนครสวรรค์ จังหวัดปทุมธานี และจังหวัดสุพรรณบุรี โดยพิจารณาปัจจัยต่างๆดังนี้ ต้นทุนค่าขนส่ง ต้นทุนการลงทุน แรงงาน ความเสี่ยงน้ำท่วม การเข้าถึงถนน การเข้าถึงลูกค้า และทัศนคติของชุมชน การวิจัยได้นำปัจจัยและทางเลือกของทำเลที่ตั้งศูนย์กระจายสินค้า มาพัฒนาเป็นโครงสร้างแผนภูมิลำดับชั้นตามกระบวนการลำดับชั้นเชิงวิเคราะห์ ผลการวิจัยพบว่า ผู้ตัดสินใจให้ความสำคัญกับปัจจัยตามลำดับความสำคัญ ดังนี้ ต้นทุนค่าขนส่ง การเข้าถึงลูกค้า ความเสี่ยงน้ำท่วม แรงงาน ต้นทุนการลงทุน ทัศนคติของชุมชน และการเข้าถึงถนน และผู้ตัดสินใจให้ความสำคัญของทางเลือกภายใต้ปัจจัยต่างๆ ตามลำดับความสำคัญ ดังนี้ จังหวัดนครสวรรค์ จังหวัดปทุมธานี และจังหวัดสุพรรณบุรี เมื่อพิจารณาร่วมกับผลการวิเคราะห์ต้นทุนค่าขนส่งพบว่า ทางเลือกที่เหมาะสมที่สุดคือจังหวัดนครสวรรค์ซึ่งมีต้นทุนค่าขนส่งต่ำที่สุด


Treatment Of Calibration Uncertainty In Multi-Baseline Cross-Correlation Searches For Gravitational Waves, J. T. Whelan, E. L. Robinson, Joseph D. Romano, E. H. Thrane Jan 2014

Treatment Of Calibration Uncertainty In Multi-Baseline Cross-Correlation Searches For Gravitational Waves, J. T. Whelan, E. L. Robinson, Joseph D. Romano, E. H. Thrane

Physics & Astronomy Faculty Publications

Uncertainty in the calibration of gravitational wave (GW) detector data leads to systematic errors, which must be accounted for in setting limits on the strength of GW signals. When cross-correlation measurements are made using data from a pair of instruments, as in searches for a stochastic GW background, the calibration uncertainties of the individual instruments can be combined into an uncertainty associated with the pair. With the advent of multi-baseline GW observation (e.g., networks consisting of multiple detectors such as the LIGO observatories and Virgo), a more sophisticated treatment is called for. We have described how the correlations between calibration …


Pt-Symmetric Acoustics, Xuefeng Zhu, Hamidreza Ramezani, Chengzhi Shi, Jie Zhu, Xiang Zhang Jan 2014

Pt-Symmetric Acoustics, Xuefeng Zhu, Hamidreza Ramezani, Chengzhi Shi, Jie Zhu, Xiang Zhang

Physics & Astronomy Faculty Publications

We introduce here the concept of acoustic parity-time (PT) symmetry and demonstrate the extraordinary scattering characteristics of the acoustic PT medium. On the basis of exact calculations, we show how an acoustic PT -symmetric medium can become unidirectionally transparent at given frequencies. Combining such a PT -symmetric medium with transformation acoustics, we design two-dimensional symmetric acoustic cloaks that are unidirectionally invisible in a prescribed direction. Our results open new possibilities for designing functional acoustic devices with directional responses.


Vanishing Power Lines And Emerging Distributed Generation, Gina S. Warren Jan 2014

Vanishing Power Lines And Emerging Distributed Generation, Gina S. Warren

Faculty Scholarship

Experts predict that distributed energy will contribute as much as twenty percent of the U.S. power supply by 2020. While no one will wake up tomorrow morning to an entirely new energy distribution system — complete with solar panels on the roof and a wind turbine in the back yard — distributed generation is receiving significant attention as the disruptive technology that will ultimately revolutionize the way energy is delivered in the United States. The reason for this shift is, in part, due to new technology that allows for more flexible localized generation of energy, and in part due to …


The Role Of Behavioral And Cognitive Cultural Orientation On Mexican American College Students’ Life Satisfaction, Lizette Ojeda, Lisa M. Edwards, Erin E. Harding, Brandy Piña-Watson Jan 2014

The Role Of Behavioral And Cognitive Cultural Orientation On Mexican American College Students’ Life Satisfaction, Lizette Ojeda, Lisa M. Edwards, Erin E. Harding, Brandy Piña-Watson

College of Education Faculty Research and Publications

We examined the role of behavioral (acculturation and enculturation) and cognitive cultural orientation (independent and interdependent self-construal) on Mexican American college students’ life satisfaction. Analyses explained 28% of the variance in life satisfaction, with social class, grade point average, and independent self-construal being unique predictors. Furthermore, enculturation was associated with increasing life satisfaction among those low in interdependent self-construal, whereas acculturation was associated with decreasing life satisfaction among those high in independent self-construal. Implications and directions for future research are discussed.


A Static Voltage Security Region For Centralized Wind Power Integration-Part I: Concept And Method, Tao Ding, Qinglai Guo, Rui Bo, Hongbin Sun, Boming Zhang Jan 2014

A Static Voltage Security Region For Centralized Wind Power Integration-Part I: Concept And Method, Tao Ding, Qinglai Guo, Rui Bo, Hongbin Sun, Boming Zhang

Electrical and Computer Engineering Faculty Research & Creative Works

When large wind farms are centrally integrated in a power grid, cascading tripping faults induced by voltage issues are becoming a great challenge. This paper therefore proposes a concept of static voltage security region to guarantee that the voltage will remain within operation limits under both base conditions and N-1 contingencies. For large wind farms, significant computational effort is required to calculate the exact boundary of the proposed security region. To reduce this computational burden and facilitate the overall analysis, the characteristics of the security region are first analyzed, and its boundary components are shown to be strictly convex. Approximate …


A Study Of Self-Concept In At-Risk Middle School Children Related To Behavior And Academic Performance, Tara Wade Franklin Jan 2014

A Study Of Self-Concept In At-Risk Middle School Children Related To Behavior And Academic Performance, Tara Wade Franklin

Electronic Theses and Dissertations

The purpose of this study was to explore the factors that are associated with the development of self-concept and how self-concept influences or interacts with academic performance and behavior. This research study asked two questions: (1) what assists in the development of self-concept, and (2) how does self-concept impact academic performance and behavior in at-risk middle school students? Using evidence-based research, parental involvement, gender, and ethnicity were selected as key factors associated with the development of self-concept in adolescence. This study proposed that students with high self-concept would have positive academic and behavioral performance. Consequently, students with low self-concept would …


Collision And Diffusion In Microwave Breakdown Of Nitrogen Gas In And Around Microgaps, J. D. Campbell, A. Bowman Iii, G. T. Lenters, Stephen K. Remillard Jan 2014

Collision And Diffusion In Microwave Breakdown Of Nitrogen Gas In And Around Microgaps, J. D. Campbell, A. Bowman Iii, G. T. Lenters, Stephen K. Remillard

Faculty Publications

The microwave induced breakdown of N-2 gas in microgaps was modeled using the collision frequency between electrons and neutral molecules and the effective electric field concept. Low pressure breakdown at the threshold electric field occurs outside the gap, but at high pressures it is found to occur inside the microgap with a large threshold breakdown electric field corresponding to a very large electron oscillation amplitude. Three distinct pressure regimes are apparent in the microgap breakdown: a low pressure multipactor branch, a mid-pressure Paschen branch, both of which occur in the space outside the microgap, and a high pressure diffusion-drift branch, …


Embedded Star Formation In S4g Galaxy Dust Lanes., Debra M. Elmegreen, Bruce G. Elmegreen, Santiago Erroz-Ferrer, Johan H. Knapen, Yaron Teich, Mark Popinchalk, E. Athanassoula, Albert Bosma, Sebastien Comeron, Yuri N. Efremov, Dimitri A. Gadotti, Armando Gil De Paz, Joannah L. Hinz, Luis C. Ho, Benne W. Holwerda, Taehyun Kim, Jarkko Laine, Eija Laurikainen, Karin Menendez-Delmestre, Trisha Mizusawa, Juan Carlos Munoz-Mateos, Michael W. Regan, Heikki Salo, Mark Seibert, Kartik Sheth Jan 2014

Embedded Star Formation In S4g Galaxy Dust Lanes., Debra M. Elmegreen, Bruce G. Elmegreen, Santiago Erroz-Ferrer, Johan H. Knapen, Yaron Teich, Mark Popinchalk, E. Athanassoula, Albert Bosma, Sebastien Comeron, Yuri N. Efremov, Dimitri A. Gadotti, Armando Gil De Paz, Joannah L. Hinz, Luis C. Ho, Benne W. Holwerda, Taehyun Kim, Jarkko Laine, Eija Laurikainen, Karin Menendez-Delmestre, Trisha Mizusawa, Juan Carlos Munoz-Mateos, Michael W. Regan, Heikki Salo, Mark Seibert, Kartik Sheth

Faculty and Staff Scholarship

Star-forming regions that are visible at 3.6 μm and Hα but not in the u, g, r, i, z bands of the Sloan Digital Sky Survey are measured in five nearby spiral galaxies to find extinctions averaging ∼3.8 mag and stellar masses averaging ∼5 × 104 M. These regions are apparently young star complexes embedded in dark filamentary shock fronts connected with spiral arms. The associated cloud masses are ∼107 M. The conditions required to make such complexes are explored, including gravitational instabilities in spiral-shocked gas and compression of incident clouds. We find that instabilities are too slow for a …


Constraining The Age Of The Ngc 4565 Hi Disk Warp : Determining The Origin Of Gas Warps., David J. Radburn-Smith, Roelof S. De Jong, David Streich, Eric F. Bell, Julianne J. Dalcanton, Andrew E. Dolphin, Adrienne M. Stilp, Antonela Monachesi, Benne W. Holwerda, Jeremy Bailin Jan 2014

Constraining The Age Of The Ngc 4565 Hi Disk Warp : Determining The Origin Of Gas Warps., David J. Radburn-Smith, Roelof S. De Jong, David Streich, Eric F. Bell, Julianne J. Dalcanton, Andrew E. Dolphin, Adrienne M. Stilp, Antonela Monachesi, Benne W. Holwerda, Jeremy Bailin

Faculty and Staff Scholarship

We have mapped the distribution of young and old stars in the gaseous H i warp of NGC 4565. We find a clear correlation of young stars (< 600 Myr) with the warp but no coincident old stars (> 1 Gyr), which places an upper limit on the age of the structure. The formation rate of the young stars, which increased ∼ 300 Myr ago relative to the surrounding regions, is (6.3+2.5 −1.5) × 10−5 M yr−1 kpc−2. This implies a ∼ 60 ± 20 Gyr depletion time of the H i warp, similar to the timescales calculated for the outer H i disks of nearby spiral galaxies. While some stars …


Ghosts I : A New Faint Very Isolated Dwarf Galaxy At D = 12 ± 2 Mpc., Antonela Monachesi, Eric F. Bell, David J. Radburn-Smith, Roelof S. De Jong, Jeremy Bailin, Julianne J. Dalcanton, Benne W. Holwerda, H. Alyson Ford, David Streich, Marija Vlajic, Daniel B. Zucker Jan 2014

Ghosts I : A New Faint Very Isolated Dwarf Galaxy At D = 12 ± 2 Mpc., Antonela Monachesi, Eric F. Bell, David J. Radburn-Smith, Roelof S. De Jong, Jeremy Bailin, Julianne J. Dalcanton, Benne W. Holwerda, H. Alyson Ford, David Streich, Marija Vlajic, Daniel B. Zucker

Faculty and Staff Scholarship

We report the discovery of a new faint dwarf galaxy, GHOSTS I, using HST/ACS data from one of our GHOSTS (Galaxy Halos, Outer disks, Substructure, Thick disk, and Star clusters) fields. Its detected individual stars populate an approximately 1 mag range of its luminosity function (LF). Using synthetic color–magnitude diagrams (CMDs) to compare with the galaxy’s CMD, we find that the colors and magnitudes of GHOSTS I’s individual stars are most consistent with being young helium-burning and asymptotic giant branch stars at a distance of ∼12±2 Mpc. Morphologically, GHOSTS I appears to be actively forming stars, so we tentatively classify …


Morphological Parameters Of A Spitzer Survey Of Stellar Structure In Galaxies., Benne W. Holwerda, J. C. Munoz-Mateos, S. Comeron, S. Meidt, K. Sheth, S. Laine, J. L. Hinz, M. W. Regan, A. Gil De Paz, K. Menendez-Delmestre, M. Seibert, T. Kim, T. Mizusawa, E. Laurikainen, H. Salo, J. Laine, D. A. Gadotti, D. Zaritsky, S. Erroz-Ferrer, L. C. Ho, J. H. Knapen, E. Athanassoula, A. Bosma, N. Pirzkal Jan 2014

Morphological Parameters Of A Spitzer Survey Of Stellar Structure In Galaxies., Benne W. Holwerda, J. C. Munoz-Mateos, S. Comeron, S. Meidt, K. Sheth, S. Laine, J. L. Hinz, M. W. Regan, A. Gil De Paz, K. Menendez-Delmestre, M. Seibert, T. Kim, T. Mizusawa, E. Laurikainen, H. Salo, J. Laine, D. A. Gadotti, D. Zaritsky, S. Erroz-Ferrer, L. C. Ho, J. H. Knapen, E. Athanassoula, A. Bosma, N. Pirzkal

Faculty and Staff Scholarship

The morphology of galaxies can be quantified to some degree using a set of scale-invariant parameters. Concentration (C), asymmetry (A), smoothness (S), the Gini index (G), the relative contribution of the brightest pixels to the secondorder moment of the flux (M20), ellipticity (E), and the Gini index of the second-order moment (GM) have all been applied to morphologically classify galaxies at various wavelengths. Here, we present a catalog of these parameters for the Spitzer Survey of stellar structure in Galaxies, a volume-limited, near-infrared (NIR) imaging survey of nearby galaxies using the 3.6 and 4.5μm channels of the Infrared Array Camera …


Gravity Effect On Electrical Field Generation And Charge Carriers Transfer During Combustion Synthesis Of Sulfides, A. A. Markov, I. A. Filimonov, Karen S. Martirosyan Jan 2014

Gravity Effect On Electrical Field Generation And Charge Carriers Transfer During Combustion Synthesis Of Sulfides, A. A. Markov, I. A. Filimonov, Karen S. Martirosyan

Physics & Astronomy Faculty Publications

The effect of gravity on the electric potential generated by the combustion synthesis of zinc sulfide is analyzed using the numerical simulation. Recent experimental studies on generation of electric voltage during combustion synthesis of zinc sulfide (ZnS) have revealed high voltage signals (4 V) with duration about 1 s, which are much higher than those produced by the gas–solid and solid–solid combustion reactions studied previously. These data have raised the question about mechanism of such a phenomenon. In our previous work we developed a novel (distributed) model describing the electric potential generation during combustion synthesis of sulfides (CSS) that didn't …


Fabrication Of Yttrium Ferrite Nanoparticles By Solution Combustion Synthesis, A. A. Saukhimov, Mkhitar A. Hobosyan, Gamage C. Dannangoda, N. N. Zhumabekova, S. E. Kumekov Jan 2014

Fabrication Of Yttrium Ferrite Nanoparticles By Solution Combustion Synthesis, A. A. Saukhimov, Mkhitar A. Hobosyan, Gamage C. Dannangoda, N. N. Zhumabekova, S. E. Kumekov

Physics & Astronomy Faculty Publications

The ternary oxide system Y-Fe-O presents fascinating magnetic properties that are sensitive to the crystalline size of particles. There is a major challenge to fabricate these materials in nano-crystalline forms due to particle conglomeration during nucleation and synthesis. In this paper we report the fabrication of nano sized crystalline yttrium ferrite by solution combustion synthesis (SCS) where yttrium and iron nitrates were used as metal precursors with glycine as a fuel. The magnetic properties of the product can be selectively controlled by adjusting the ratio of glycine to metal nitrates. Yttrium ferrite nano-powder was obtained by using three concentration of …


Free-Energy Calculations For Semi-Flexible Macromolecules: Applications To Dna Knotting And Looping, Stefan M. Giovan, Robert G. Scharein, Andreas Hanke, Stephen D. Levene Jan 2014

Free-Energy Calculations For Semi-Flexible Macromolecules: Applications To Dna Knotting And Looping, Stefan M. Giovan, Robert G. Scharein, Andreas Hanke, Stephen D. Levene

Physics & Astronomy Faculty Publications

We present a method to obtain numerically accurate values of configurational free energies of semiflexible macromolecular systems, based on the technique of thermodynamic integration combined with normal-mode analysis of a reference system subject to harmonic constraints. Compared with previous free-energy calculations that depend on a reference state, our approach introduces two innovations, namely, the use of internal coordinates to constrain the reference states and the ability to freely select these reference states. As a consequence, it is possible to explore systems that undergo substantially larger fluctuations than those considered in previous calculations, including semiflexible biopolymers having arbitrary ratios of contour …


Report To The Chicago Park District On Conflicts With Ring-Billed Gulls And The 2014 Integrated Ring-Billed Gull Damage Management Project, M. L. Bloomquist, J.W. Hartmann, T.G. Guerrant, S. F. Beckerman, R. M. Engeman Jan 2014

Report To The Chicago Park District On Conflicts With Ring-Billed Gulls And The 2014 Integrated Ring-Billed Gull Damage Management Project, M. L. Bloomquist, J.W. Hartmann, T.G. Guerrant, S. F. Beckerman, R. M. Engeman

United States Department of Agriculture Wildlife Services: Staff Publications

The large ring-billed gull (Larus delawarensis) population in the City of Chicago has caused various conflicts including general nuisance, property damage, economic losses, and threats to human health and safety. Several studies have shown a relationship between ring-billed gulls and increased levels of fecal indicator bacteria (FIB) such as Escherichia coli (E. coli) in nearshore waters. Results of tests for E. coli have led to the issuance of swim advisories at Chicago beaches.

The objectives of the Chicago Ring-billed Gull Damage Management Project were to (1) reduce the local production of ring-billed gulls, (2) reduce the …


Incorporating Cold-Air Pooling Into Downscaled Climate Models Increases Potential Refugia For Snow-Dependent Species Within The Sierra Nevada Ecoregion, Ca, Jennifer A. Curtis, Lorraine E. Flint, Alan L. Flint, Jessica D. Lundquist, Brian Hudgens, Erin E. Boydston, Julie K. Young Jan 2014

Incorporating Cold-Air Pooling Into Downscaled Climate Models Increases Potential Refugia For Snow-Dependent Species Within The Sierra Nevada Ecoregion, Ca, Jennifer A. Curtis, Lorraine E. Flint, Alan L. Flint, Jessica D. Lundquist, Brian Hudgens, Erin E. Boydston, Julie K. Young

United States Department of Agriculture Wildlife Services: Staff Publications

We present a unique water-balance approach for modeling snowpack under historic, current and future climates throughout the Sierra Nevada Ecoregion. Our methodology uses a finer scale (270 m) than previous regional studies and incorporates cold-air pooling, an atmospheric process that sustains cooler temperatures in topographic depressions thereby mitigating snowmelt. Our results are intended to support management and conservation of snow-dependent species, which requires characterization of suitable habitat under current and future climates. We use the wolverine (Gulo gulo) as an example species and investigate potential habitat based on the depth and extent of spring snowpack within four National …


Calving Location Selection Patterns Of Saiga Antelope In Mongolia, B. Buuveibaatar, T. K. Fuller, J. K. Young, J. Berger Jan 2014

Calving Location Selection Patterns Of Saiga Antelope In Mongolia, B. Buuveibaatar, T. K. Fuller, J. K. Young, J. Berger

United States Department of Agriculture Wildlife Services: Staff Publications

Habitat selection for calving by ungulates is an important behavioral trait because it affects neonate survival. Generally, ungulate calving site selection varies by vulnerability to predators, local topography, habitat quality and level of human disturbance. The Mongolian saiga (Saiga tatarica mongolica) is endemic to Mongolia where a threatened population of ∼7000 exists in the northern Gobi Desert. We analyzed factors that could affect selection of saiga calving locations in the Sharga Nature Reserve, western Mongolia, using data obtained from ground surveys over 4 years between 2008 and 2012. Multiple factors explain calving location selection by saiga antelopes, based …


Determination Of Residue Levels Of Alphachloralose In Duck Tissues, David A. Goldade, Randal S. Stahl, John J. Johnston Jan 2014

Determination Of Residue Levels Of Alphachloralose In Duck Tissues, David A. Goldade, Randal S. Stahl, John J. Johnston

United States Department of Agriculture Wildlife Services: Staff Publications

Alpha-chloralose (AC) is used to capture nuisance waterfowl so that they can be relocated. Concerns for food safety limit its use prior to or during the waterfowl hunting season. To determine its half-life in tissue, we administered AC to adult male (n = 7) and female (n = 5) mallard ducks (Anas platyrhynchos) via oral gavage. A gel capsule containing 100 μCi of radioactive AC (14C-AC) and sufficient nonlabeled AC to produce a dose of approximately 30 mg/kg was given to each duck.The ducks were euthanized at 2, 6, 10, and 18 hours postdosing (n = …


Geographic Segregation And Evidence Of Density-Dependent Changes In Sex Ratios In An Abundant Colonial Waterbird, Brian S. Dorr, Katie C. Hanson-Dorr, Travis L. Devault, Alban Guillaumet, Scott C. Barras Jan 2014

Geographic Segregation And Evidence Of Density-Dependent Changes In Sex Ratios In An Abundant Colonial Waterbird, Brian S. Dorr, Katie C. Hanson-Dorr, Travis L. Devault, Alban Guillaumet, Scott C. Barras

United States Department of Agriculture Wildlife Services: Staff Publications

Demographic information, such as geographic segregation of sexes and sex ratio data, is needed to develop, model and evaluate conservation and management strategies for wildlife. A variety of physiological, behavioral and environmental factors can influence segregation of sexes and sex ratios, many of which originate with density- dependent processes. Departure from 50:50 sex ratios of double-crested cormorants (Phalacrocorax auritus) collected during control efforts in breeding and wintering areas across their eastern range of the USA were evaluated using using a Z-test as well as Stouffer’s weighted Z-tests. In addition, a specifically-designed randomization test was used to evaluate density-dependent …


Evaluation Of Techniques To Reduce Deer And Elk Damage To Agricultural Crops, Heather E. Johnson, Justin W. Fischer, Matthew Hammond, Patricia D. Dorsey, W. David Walter, Charles Anderson, Kurt C. Vercauteren Jan 2014

Evaluation Of Techniques To Reduce Deer And Elk Damage To Agricultural Crops, Heather E. Johnson, Justin W. Fischer, Matthew Hammond, Patricia D. Dorsey, W. David Walter, Charles Anderson, Kurt C. Vercauteren

United States Department of Agriculture Wildlife Services: Staff Publications

Mule deer (Odocoileus hemionus) and Rocky Mountain elk (Cervus elaphus nelsoni) provide important recreational, ecological, and economic benefits, but can also cause substantial damage to agricultural crops. Cervid damage to agriculture creates challenges for wildlife agencies responsible for minimizing crop depredation while maintaining healthy deer and elk populations. Sunflower producers in southwestern Colorado, USA, have experienced high deer and elk damage and were interested in temporary methods to reduce damage that were cost-effective for rotational crops. To address this challenge, we investigated 3 temporary, non-lethal exclusion and repellent techniques for reducing deer and elk damage to …


Improved Satellite Transmitter Harness Attachment Technique, John S. Humphrey, Michael L. Avery Jan 2014

Improved Satellite Transmitter Harness Attachment Technique, John S. Humphrey, Michael L. Avery

United States Department of Agriculture Wildlife Services: Staff Publications

Kenward et al. (2001) observed: ‘‘Techniques for studying animals should not prejudice either the welfare of the individuals or the scientific quality of the results. This is especially important when advances in technology create new opportunities, as well as new risks.’’ Satellite telemetry technology has revolutionized the ability of scientists to conduct long-term studies of avian movements and behavior (e.g., Prince et al. 1992, Cappelle et al. 2011, Chevallier et al. 2011). Effective application of this technology depends on many factors, including the proper attachment of the transmitter to the bird. For large birds, transmitters are attached using a backpack-style …


Environmental Contaminant Concentrations In Canada Goose (Branta Canadensis) Muscle: Probabilistic Risk Assessment For Human Consumers, Katherine E. Horak, Richard Chipman, Lisa Murphy, John Johnston Jan 2014

Environmental Contaminant Concentrations In Canada Goose (Branta Canadensis) Muscle: Probabilistic Risk Assessment For Human Consumers, Katherine E. Horak, Richard Chipman, Lisa Murphy, John Johnston

United States Department of Agriculture Wildlife Services: Staff Publications

The issue of food insecurity affects millions of people in the United States every year. Often these people rely on soup kitchens, food banks, and shelters for proper meals, and these organizations often depend on donations to meet needs. One of the most limited food resources is meat. To help alleviate this problem, the U.S. Department of Agriculture Wildlife Services donates more than 60 tons of wild game (deer, moose, feral hogs, goats, geese, and ducks) to a variety of charitable organizations each year. Although commercially produced meat routinely undergoes screening for contaminants, potential exposure to environmental contaminants from eating …


Effects Of Spatiotemporal Resource Heterogeneity On Home Range Size Of American Beaver, L. F. Mcclintic, J. D. Taylor Ii, J. C. Jones, R. D. Singleton, G. Wang Jan 2014

Effects Of Spatiotemporal Resource Heterogeneity On Home Range Size Of American Beaver, L. F. Mcclintic, J. D. Taylor Ii, J. C. Jones, R. D. Singleton, G. Wang

United States Department of Agriculture Wildlife Services: Staff Publications

Home range size of terrestrial animals may be influenced by spatiotemporal dynamics of resources. However, little is known regarding the effects of spatiotemporal resource availability on semi-aquatic central place foragers such as the American beaver Castor canadensis. From January 2011 to April 2012, 26 beavers at 11 wetlands at Redstone Arsenal in north-central Alabama, USA, were captured and radio-tracked using radio telemetry. The objectives of this study were to test the predictions of three hypotheses: (1) the resource dispersion hypothesis: more spatially dispersed resources throughout a landscape increase home range sizes; (2) the temporal resource variability hypothesis: more temporally …


The Spring Migration Of Adult North American Ospreys, Mark S. Martell, Richard O. Bierregaard Jr., Brian E. Washburn, John E. Elliott, Charles J. Henry, Robert S. Kennedy, Iain Macleod Jan 2014

The Spring Migration Of Adult North American Ospreys, Mark S. Martell, Richard O. Bierregaard Jr., Brian E. Washburn, John E. Elliott, Charles J. Henry, Robert S. Kennedy, Iain Macleod

United States Department of Agriculture Wildlife Services: Staff Publications

Most North American Ospreys (Pandion haliaetus) are migratory, breeding in northern latitudes and migrating long distances to and from their wintering grounds in the tropics. Although fall migration patterns of North American Ospreys have been described and studied, very little has been published about the spring migration of these birds. We used satellite telemetry to: (1) determine the characteristics (timing, duration, migratory routes) of spring migrations of Ospreys; (2) determine if differences in spring migration patterns existed between sexes and among three breeding populations (east coast, midwestern, and western); and (3) compare consecutive fall and spring migrations of …


The Influence Of Breeding Experience On Nest Success In Red-Winged Blackbird, George M. Linz, Richard S. Sawin, Mark W. Lutman Jan 2014

The Influence Of Breeding Experience On Nest Success In Red-Winged Blackbird, George M. Linz, Richard S. Sawin, Mark W. Lutman

United States Department of Agriculture Wildlife Services: Staff Publications

The Red-winged Blackbird (Agelaius phoeniceus) is a polygynous species, and females are typically responsible for the majority of parental care. Despite their limited involvement, males can contribute to reproduction through nest defense and the feeding of nestlings. Some aspects of nest defense may be learned, and older males are more likely to feed young, suggesting that males with previous breeding experience may enjoy higher nest success than their naïve counterparts. We manipulated territory ownership on 10 wetlands in central North Dakota in order to examine the influence of breeding experience on reproductive success. We found no evidence that …


Regulation Of Tree Squirrel Populations With Immunocontraception: A Fox Squirrel Example, Sara K. Krause, Douglas A. Kelt, Dirk H. Van Vuren, James P. Gionfriddo Jan 2014

Regulation Of Tree Squirrel Populations With Immunocontraception: A Fox Squirrel Example, Sara K. Krause, Douglas A. Kelt, Dirk H. Van Vuren, James P. Gionfriddo

United States Department of Agriculture Wildlife Services: Staff Publications

Tree squirrels (Sciurus spp.) are highly successful immigrants to urban and suburban areas in North America and Europe, causing both economic and ecological damage. Control of such invasive populations is challenging but of increasing importance to local managers. We studied an invasive population of fox squirrels (S. niger) and applied an immunocontraceptive vaccine in an experimental study of demographic control. Here we integrate our data into a simple stage-structured population model to simulate population reduction under 2 treatment levels (60 and 80% of females, respectively) for vaccines lasting from 1 to 5 years. Contraception can be an …


Diffusion Of Influenza Viruses Among Migratory Birds With A Focus On The Southwest United States, Matthew Scotch, Tommy Tsan-Yuk Lam, Kristy L. Pabilonia, Theodore Anderson, John Baroch, Dennis Kohler, Thomas J. Deliberto Jan 2014

Diffusion Of Influenza Viruses Among Migratory Birds With A Focus On The Southwest United States, Matthew Scotch, Tommy Tsan-Yuk Lam, Kristy L. Pabilonia, Theodore Anderson, John Baroch, Dennis Kohler, Thomas J. Deliberto

United States Department of Agriculture Wildlife Services: Staff Publications

The Southwest United States, including Arizona and New Mexico, has a diverse climate and is home to many different avian species. We sequenced the hemagglutinin (HA) gene of twenty influenza specimens for the years 2007–2009. This included four from Arizona, and sixteen from New Mexico. We analyzed the sequences and determined the following HA subtypes: H3, H4, H6, H8, and H11. For each subtype, we combined our virus sequences with those from a public database, and inferred phylogeographic models of influenza diffusion. Statistical phylogeography indicated that overall evolutionary diffusion of avian influenza viruses is geographically structured (p < 0.05). In addition, we found that diffusion to the Southwest was often from nearby states including California. For H3, H4 and H6, the intra-flyway gene flow rates were significantly (p < 0.001) higher than those of inter-flyway. Such rate difference was also observed in H8 and H11, yet, without statistical significance (p = 0.132, p = 0.190, respectively). Excluding any one flyway from the calculation generated similar results, suggesting that such barrier effect on gene flow rates is not exclusively produced by any single flyway. We also calculated the Bayes factor test for the significant non-zero rates between states and identified significant routes both within and across flyways. Such inter-flyway spread of influenza was probably the result of birds from four flyways co-mingling on breeding grounds in northern regions or marshaling on staging areas post breeding in Canada or Alaska, before moving south each fall. This study provides an initial analysis of evolutionary diffusion of avian influenza virus to and from the Southwest United States. However, more sequences from this region need to be generated to determine the role of host migration and other factors on influenza diffusion.


Behavioral Traits And Airport Type Affect Mammal Incidents With U.S. Civil Aircraft, Kristin B. Schwarz, Jerrold L. Belant, James A. Martin, Travis L. Devault, Guiming Wang Jan 2014

Behavioral Traits And Airport Type Affect Mammal Incidents With U.S. Civil Aircraft, Kristin B. Schwarz, Jerrold L. Belant, James A. Martin, Travis L. Devault, Guiming Wang

United States Department of Agriculture Wildlife Services: Staff Publications

Wildlife incidents with aircraft cost the United States (U.S.) civil aviation industry >US$1.4 billion in estimated damages and loss of revenue from 1990 to 2009. Although terrestrial mammals represented only 2.3 % of wildlife incidents, damage to aircraft occurred in 59 % of mammal incidents. We examined mammal incidents (excluding bats) at all airports in the Federal Aviation Administration (FAA) National Wildlife Strike Database from 1990 to 2010 to characterize these incidents by airport type: Part-139 certified (certificated) and general aviation (GA). We also calculated relative hazard scores for species most frequently involved in incidents. We found certificated airports had …