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Current Zoology 2011年第5期57卷 648-654页

作者： Jim GRAHAM Catherine JARNEVICH Nick YOUNG greg NEWMAN Thomas STOHLGREN Natural Resource Ecology Laboratory Colorado State University Fort Collins CO 80523-1499 USA Fort Collins Science Center U.S. Geological Survey 2150 Centre Ave. Building C Fort Collins CO 80526 USA

Habitat suitability models have been used to predict the present and future potential distribution of a variety of spe- cies. Eurasian tree sparrows Passer montanus, native to Eurasia, have established populations in other parts of the world. In North America, their current distribution is limited to a relatively small region around its original introduction to St. Louis, Missouri. We combined data from the Global Biodiversity Information Facility with current and future climate data to create habitat suitability models using Maxent for this species. Under projected climate change scenarios, our models show that the distribution and range of the Eurasian tree sparrow could increase as far as the Pacific Northwest and Newfoundland. This is potentially important in-formation for prioritizing the management and control of this non-native species [Current Zoology 57 （5）： 648--654, 2011].

关键词： Eurasian tree sparrows Passer montanus Maxent Climate change Distribution model

Radon bearing water protection in underground uranium mining--A case study

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International Journal of Mining Science and Technology 2017年第4期27卷 599-603页

作者： Yun Xiaoyou Tang Baoyao greg Murdock Brian McGill Brian Mattie McArthur River Operation Cameco Corporation Saskatoon S7M 1J3 Canada

High pressure, radon bearing water has been identified as one of the most critical challenges in mining the high-grade uranium deposit at the Mc Arthur River Operation, Cameco Corporation. The ore deposits are located between 490 and 640 m below the surface and surrounded by water bearing Athabasca sandstone, a graphitic P2 fault zone, and highly altered ground. This paper introduces the inflow risk management program at Mc Arthur River Operation, which includes various hydrogeological challenges and the corresponding strategies applied, such as risk-based probe and grout programs(geological, hydrogeological, and geotechnical), ground freezing programs, and comprehensive ground control programs. These programs have been developed, tested, and proven successful over years of mining practices. Working with this world class deposit of high risk and low tolerance, it is believed that these experiences might be beneficial to other mining operations with similar hydrogeological characteristics.

关键词： Inflow risk management Geotechnical and development probe and grout programs Dewatering infrastructure Ground freezing Ground control

Inferring topological transitions in pattern-forming processes with self-supervised learning

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npj Computational Materials 2022年第1期8卷 1970-1981页

作者： Marcin Abram Keith Burghardt greg Ver Steeg Aram Galstyan Remi Dingreville Department of Physics and Astronomy University of Southern CaliforniaLos AngelesCA90089USA Information Sciences Institute University of Southern CaliforniaMarina del ReyCA90292USA Center for Integrated Nanotechnologies Nanostructure Physics DepartmentSandia National LaboratoriesAlbuquerqueNM87185USA

The identification of transitions in pattern-forming processes are critical to understand and fabricate microstructurally precise materials in many application *** supervised methods can be useful to identify transition regimes,they need labels,which require prior knowledge of order parameters or relevant microstructures describing these ***,we develop a self-supervised,neural-network-based approach that does not require predefined labels about microstructure classes to predict process parameters from observed *** show that assessing the difficulty of solving this inverse problem can be used to uncover microstructural *** demonstrate our approach by automatically discovering microstructural transitions in two distinct pattern-forming processes:the spinodal decomposition of a two-phase mixture and the formation of binary-alloy microstructures during physical vapor deposition of thin *** approach opens a path forward for discovering unseen or hard-to-discern transitions and ultimately controlling complex pattern-forming processes.

关键词： alloy microstructure transitions

Physically Based Rendering: From Theory to Implementation

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Continuous-time proportional-integral distributed optimisation for networked systems

丛书名： The Interactive 3d Technology Series

2004年

作者： Pharr, Matt Humphreys, greg

ISBN: (数字)9780080538969

ISBN: (纸本)9780125531801

Rendering is a crucial component of computer graphicsthe conversion of a description of a 3D scene into an image for display. Algorithms for animation, geometric modeling, and texturing all must feed their results through some sort of rendering process for the results to be visible in an image. Focusing on realistic images, physically based rendering incorporates ideas from a range of disciplines, including physics, biology, psychology, cognitive science, and mathematics. This book presents the algorithms of modern photorealistic rendering and follows step by step the creation of a complete rendering system. As each new rendering concept is introduced it is also shown implemented in codehere is no better way to understand the subtle and complex process of rendering. The code itself is highly readable, written in the literate programming style that mixes text describing the system with the code that implements it. The result is a stunning achievement in graphics education for students, professionals, and researchers.*CD-ROM with the source code for a complete rendering system for Windows, OS X, & Linuxith many examples of images created by the system throughout the 4 color text*The code and text are tightly woven together through the technique of literate programming with a unique indexing feature that lists all locations of functions, variables, and methods on the page they are first described*The most complete guide to understanding, designing, and building a rendering system

关键词： Computer graphics.

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Journal of Control and Decision 2014年第3期1卷 191-213页

作者： greg Droge Hiroaki Kawashima Magnus B.Egerstedt School of Electrical and Computer Engineering Georgia Institute of TechnologyAtlantaGAUSA Graduate School of Informatics Kyoto UniversityKyotoJapan

In this paper,we explore the relationship between dual decomposition and the consensusbased method for distributed *** relationship is developed by examining the similarities between the two approaches and their relationship to gradient-based constrained *** formulating each algorithm in continuous-time,it is seen that both approaches use a gradient method for optimisation with one using a proportional control term and the other using an integral control term to drive the system to the constraint ***,a significant contribution of this paper is to combine these methods to develop a continuous-time proportional-integral distributed optimisation ***,we establish convergence using Lyapunov stability techniques and utilising properties from the network structure of the multi-agent system.

关键词： distributed optimisation multi-agent control networked systems

Animal models of genetic causes of male infertility

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Asian Journal of Andrology 2002年第3期4卷 213-219页

作者： greg L. Christensen Douglas T. Carrell Andrology Department University of Utah School of Medicine Salt Lake City Utah 84132 USAAndrology Department University of Utah School of Medicine Salt Lake City Utah 84132 USA

Introduction In the past 10 years, more than 100 different genetically engineered mice have been developed with an abnormality in spermatogenesis. More than half of these male infertility animal models have been reported in the past three years alone. Spermatogenic defects in these models vary considerably, ranging from the inappropriate migration of primordial germ cells to the inability of mature spermatozoa to bind the zona pellucida. Many of

关键词： animal models genes genetics knockout male infertility

Roles of SO_2 oxidation in new particle formation events

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Journal of Environmental Sciences 2015年第4期27卷 90-101页

作者： He Meng Yujiao Zhu greg J.Evans Cheol-Heon Jeong Xiaohong Yao Key Lab of Marine Environmental Science and Ecology Ministry of Education Ocean University of China Southern Ontario Centre for Atmospheric Aerosol Research University of Toronto

The oxidation of SO2 is commonly regarded as a major driver for new particle formation（NPF） in the atmosphere. In this study, we explored the connection between measured mixing ratio of SO2 and observed long-term（duration 〉 3 hr） and short-term（duration〈 1.5 hr） NPF events at a semi-urban site in Toronto. Apparent NPF rates（J30） showed a moderate correlation with the concentration of sulfuric acid（[H2SO4]） calculated from the measured mixing ratio of SO2 in long-term NPF events and some short-term NPF events（Category I）（R^2= 0.66）. The exponent in the fitting line of J30~ [H2SO4]nin these events was1.6. It was also found that SO2 mixing ratios varied a lot during long-term NPF events,leading to a significant variation of new particle counts. In the SO2-unexplained short-term NPF events（Category II）, analysis showed that new particles were formed aloft and then mixed down to the ground level. Further calculation results showed that sulfuric acid oxidized from SO2 probably made a negligible contribution to the growth of 〉 10 nm new particles.

关键词： Nucleation Particle growth Sulfuric acid Photochemical oxidation SO2

The role of lactose in weanling pig nutrition:a literature and meta-analysis review

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Journal of Animal Science and Biotechnology 2021年第2期12卷 462-478页

作者： Jinbiao Zhao Zeyu Zhang Shuai Zhang greg Page Neil W.Jaworski State Key Laboratory of Animal Nutrition College of Animal Science and TechnologyChina Agricultural UniversityNo.2 Yuanmingyuan West RoadBeijing 100193China Trouw Nutrition Innovation Stationsstraat 773800AG AmersfoortNetherlands

Lactose plays a crucial role in the growth performance of pigs at weaning because it is a palatable and easily digestible energy source that eases the transition from milk to solid ***,the digestibility of lactose declines after weaning due to a reduction in endogenous lactase activity in *** a result,some lactose may be fermented in the gastrointestinal tract of *** of lactose by intestinal microbiota yields lactic acid and volatile fatty acids,which may positively regulate the intestinal environment and microbiome,resulting in improved gastrointestinal health of weanling *** hypothesize that the prebiotic effect of lactose may play a larger role in weanling pig nutrition as the global feed industry strives to reduce antibiotic usage and pharmacological levels of zinc oxide and supra-nutritional levels of *** presented in this review indicates that high dietary lactose improves growth performance of piglets,as well as the growth of beneficial bacteria,particularly Lactobacillus,with the positive effects being more pronounced in the first 2 weeks after ***,the risk of post-weaning diarrhea may increase as pigs get older due to reduced lactase activity,high dietary lactose concentrations,and larger feed intakes,all of which may lead to excessive lactose fermentation in the intestine of the ***,dietary lactose levels exert different effects on growth performance and gastrointestinal physiological functions in different feeding phases of weanling ***,no formal recommendation of lactose for weanling pigs has been reported.A meta-analysis approach was used to determine that diets fed to swine should include 20%,15%,and 0 lactose from d 0-7,d 7-14,and d 14-35 post-weaning,***,sustainable swine production demands that economics must also be taken into account as lactose and lactose containing ingredients are ***,alternatives to lactose,so called“lactose equivalents

关键词： Growth performance Gut health Gut microbiota Lactose Lactose equivalents Weanling pig

Approximating Nonlinear Relations Between Susceptibility and Magnetic Contents in Rocks Using Neural Networks

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Tsinghua Science and Technology 2010年第3期15卷 281-287页

作者： William W Guo Michael Li Zhengxiang Li greg Whymark Faculty of Arts Business lnformatics and Education Central Queensland University Rockhampton QLD 4701 Australia The Institute for Geoscience Research (TIGER) Curtin University of Technology Perth WA 6845 Australia

Correlations between magnetic susceptibility and contents of magnetic minerals in rocks are important in interpreting magnetic anomalies in geophysical exploration and understanding magnetic behaviors of rocks in rock magnetism studies. Previous studies were focused on describing such correlations using a sole expression or a set of expressions through statistical analysis. In this paper, we use neural network techniques to approximate the nonlinear relations between susceptibility and magnetite and/or hematite contents in rocks. This is the first time that neural networks are used for such study in rock magnetism and magnetic petrophysics. Three multilayer perceptrons are trained for producing the best possible estimation on susceptibility based on magnetic contents. These trained models are capable of producing accurate mappings between susceptibility and magnetite and/or hematite contents in rocks. This approach opens a new way of quantitative simulation using neural networks in rock magnetism and petrophysical research and applications.

关键词： neural networks nonlinear function approximation rock magnetism magnetic susceptibility magnetic contents

Hip hemi-arthroplasty for neck of femur fracture:What is the current evidence?

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World Journal of Orthopedics 2018年第11期9卷 235-244页

作者： greg AJ Robertson Alexander M Wood Edinburgh Orthopaedic Trauma Unit Royal Infirmary of Edinburgh Orthopaedic Department Leeds General Infirmary

This editorial reviews and summarises the current evidence(meta-analyses and Cochrane reviews) relating to the use of hip hemi-arthroplasty for neck of femur fractures. Regarding the optimal surgical approach,two recent meta-analyses have found that posterior approaches are associated with: higher rates of dislocation compared to lateral and anterior approaches; and higher rates of re-operation compared to lateral approaches. Posterior approaches should therefore be avoided when performing hip hemi-arthroplasty procedures. Assessing the optimal prosthesis head component,three recent meta-analyses and one Cochrane review have found that while unipolar hemiarthroplasty can be associated with increased rates of acetabular erosion at short-term follow-up(up to 1 year),there is no significant difference between the unipolar hemi-arthroplasty and bipolar hemi-arthroplasty for surgical outcome,complication profile,functional outcome and acetabular erosion rates at longer-term follow-up(2 to 4 years). With bipolar hemi-arthroplasty being the more expensive prosthesis,unipolar hemi-arthroplasty is the recommended option. With regards to the optimal femoral stem insertion technique,three recent metaanalyses and one Cochrane Review have found that,while cemented hip hemi-arthroplasties are associated with a longer operative time compared to uncemented Hip Hemi-arthroplasties,cemented prostheses have lower rates of implant-related complications(particularly peri-prosthetic femoral fracture) and improved postoperative outcome regarding residual thigh pain and mobility. With no significant difference found between the two techniques for medical complications and mortality,cemented hip hemi-arthroplasty would appear to be the superior technique. On the topic of wound closure,one recent meta-analysis has found that,while staples can result in a quicker closure time,there is no significant difference in post-operative infections rates or wound healing outcomes when comparing staples

关键词： Hemi-arthroplasty Prosthesis Stem Head Hip Femoral Neck Fracture Cement