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Scientific challenges and instrumentation for the International Meridian Circle Program

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Science China Earth Sciences 2021年第12期64卷 2090-2097页

作者： William LIU Michel BLANC Chi WANG Eric DONAVAN John foster Mark LERTER Hermann OPGENOOTYH Liwen REN National Space Science Centre Chinese Academy of SciencesBeijing100190China University of Toulouse Toulouse31400France University of Calgary CalgaryT2N 1N4Canada MIT Haystack Observatory CambridgeMA01886USA University of Leicester LeicesterLE17RHUK University of Umeå UmeåSE-90187Sweden

Earth’s ecosystems and human activities are threatened by a broad spectrum of hazards of major importance for the safety of ground infrastructures,space systems and space flight:solar activity,earthquakes,atmospheric and climatic disturbances,changes in the geomagnetic field,fluctuations of the global electric *** and understanding these major hazards to better predict and mitigate their effects is one of the greatest scientific and operational challenges of the 21st *** diverse,these hazards share one feature in common:they all leave their characteristic imprints on a critical layer of the Earth’s environment:its ionosphere,middle and upper atmosphere(IMUA).The objective of the International Meridian Circle Program(IMCP),a major international program led by the Chines Academy of Sciences(CAS),is to deploy,integrate and operate a global network of research and monitoring instruments to use the IMUA as a screen on which to detect these *** this article,we first show that the geometry required for the IMCP global observation system leads to a deployment of instruments in priority along the 120°E-60°W great meridian circle,which will cover in an optimal way both the dominant geographic and geomagnetic latitude variations,possibly complemented by a second Great Circle along the 30°E-150°W meridians to capture longitude ***,starting from the Chinese Meridian Project(CMP)network and using it as a template,we give a preliminary and promising description of the instruments to be integrated and deployed along the 120°E-60°W great circle running across China,Australia and the Americas.

关键词： International Meridian Circle Program Ionosphere Middle-upper atmosphere Space weather Chinese Meridian Project

Feasibility of hydrogen fuel cell technology for railway intercity services:a case study for the Piedmont in North Carolina

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Railway Engineering Science 2021年第3期29卷 258-270页

作者： Orwell Madovi Andreas Hoffrichter Nick Little Shanelle N.foster Raphael Isaac Department of Electrical and Computer Engineering Michigan State University428 South Shaw LaneRoom 2120East LansingMI 48824USA Center for Railway Research&Education Broad College of BusinessMichigan State University3535 Forest RoadRoom C-36LansingMI 48910USA

Diesel fuel combustion results in exhaust containing air pollutants and greenhouse gas *** railway vehicles use diesel fuel as their energy *** emissions,as well as concerns about economical,alternative power supply,have driven efforts to move to hydrogen motive *** fuel cell technology applied to railways offers the opportunity to eliminate harmful exhaust emissions and the potential for a low-or zero-emission energy supply ***,only multiple-unit trains with hydrail technology operate *** of an Integrated Hybrid Train Simulator for intercity railway is *** proposed tool incorporates the effect of powertrain components during the wheel-to-tank *** to its predecessors,the proposed reconfigurable tool provides high fidelity with medium requirements and minimum computation *** train simulation and the federal government’s Greenhouse gases,Regulated Emissions,and Energy use in Transportation(GREET)model are used in combination to evaluate the feasibility of various train and powertrain *** Piedmont intercity service operating in North Carolina is used as a case *** study includes six train configurations and powertrain options as well as nine hydrogen supply options in addition to the diesel *** results show that a hydrail option is not only feasible,but a low-or zero-carbon hydrogen supply chain could be possible.

关键词： Hydrail Life cycle assessment Criteria pollutants Well-to-wheel Single train simulation Modeling

藏东昌都地区首次发现中侏罗世兽脚类恐龙行迹

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地球科学 2022年第11期47卷 4222-4244页

作者：李炎桂姚华舟 William J.foster 邢立达王传尚 Asma Tahir Junaid Khan 安志辉赵赫王建雄中国地质调查局武汉地质调查中心湖北武汉430205 中国地质大学地质调查研究院湖北武汉430074 古生物与地质环境演化湖北省重点实验室湖北武汉430205 汉堡大学地质学院德国汉堡201465 中国地质大学北京100083

藏东昌都地区阿涅塘化石点中侏罗世达布卡组滨湖相紫红色中-细砂岩中,发现以凸形迹完好地保存的4层恐龙足迹,包括Grallator类、大型兽脚类、小型兽脚类和小型蜥脚类等足迹类型,并构成两列完美的行迹.组成行迹T1的4个Grallator类足迹被... 详细信息

藏东昌都地区阿涅塘化石点中侏罗世达布卡组滨湖相紫红色中-细砂岩中,发现以凸形迹完好地保存的4层恐龙足迹,包括Grallator类、大型兽脚类、小型兽脚类和小型蜥脚类等足迹类型,并构成两列完美的行迹.组成行迹T1的4个Grallator类足迹被命名为Grallator anietangensis ***.,对其进行了详细的形态学分析,并讨论了造迹恐龙的大小和运动状态,这是Grallator类足迹在西藏地区的首次发现.组成行迹T2的9个大型兽脚类足迹被归为Theropoda *** ***.,对该类足迹进行了形态描述和功能分析;这类足迹在中国是首次记录,其连续且清晰的尾迹表明造迹者并非处于正常运动状态,而是应对某种特殊境况的特别行为方式,即其正以昂起的前躯一边观察,一边以极低的速度前进,因前躯昂起,尾部相应下垂,从而留下尾迹.两列行迹均显示出造迹者正沿古昌都湖岸前进.中国迄今所发现的恐龙骨骼和Grallator类足迹化石主要表现为以西南地区为中心,再向四周不断发散的扩散模式,但Grallator类足迹化石综合提供的信息显示恐龙动物的扩散速度比骨骼化石反映的速度更快.

关键词：兽脚类足迹恐龙中侏罗世达布卡组藏东昌都地区

Ants as architects of living,self-healing structures

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医用生物力学 2013年第S1期28卷 30-32页

作者： David Hu Nathan Mlot Craig Tovey Paul foster Schools of Mechanical Engineering Georgia Institute of Technology Schools of Biology Georgia Institute of Technology School of Industrial Systems Engineering Georgia Institute of Technology

We present experiments and theory on the ability of fire ants to both flow like a fluid and aggregate like a *** floods,fire ants link their bodies together to weave hydrophobic rafts in the manner of *** returning to land,they construct bivouacs that are shaped such that each ant supports an equal load throughout *** attention is paid to rationalizing construction rates based upon individual behaviors and constraints of the *** ant species form functional self-assemblages by linking themselves *** viewed collectively,a fire ant self-assemblage exhibits bulk material characteristics,such as the ability to flow or support *** assemblages can be constructed and disassembled ***

关键词： assemblage aggregate themselves linking quickly floods constraints tower manner shaped

Tiny insects against the weather flight and foraging patterns of Frankliniella schultzei (Thripidae) not altered by onset of rainfall

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Insect Science 2018年第6期25卷 1119-1127页

作者： Lachlan C.Jones Brodie J.foster Michelle A.Rafter Gimme H.Walter School of Biological Sciences The University of QueenslandSt LuciaBrisbaneQueenslandAustrafia

To survive in nature,organisms may need to take direct action to mitigate specific dangers from their environmental *** flying insects are thought to be at particular risk from rainfall that would be of negligible concern to larger *** study species Frankliniella schultzei is a thrips that inhabits flowers and feeds mostly on petal tissue and *** found to respond in the laboratory to decreases in atmospheric pressure associated with cyclonic conditions (rather than merely heavy rainfall),their responses to conditions preceding rainfall have not been tested in the *** field sampling investigated the relationship between floral development and sites at which male,female,and larval thrips were generally present on sunny *** then designed a sampling strategy to test if these thrips can anticipate imminent rainfall or storms and so seek shelter deep within flowers,by sampling host flowers (in sections)on multiple days with different weather *** traps were used to intercept thrips in flight,thus providing a measure of flight behavior across different *** initial sampling found adult thrips primarily at the petal apex of anthesis-stage flowers where pollen is distributed. We subsequently found that rainfall,atmospheric pressure change,temperature,humidity and wind had no effect on flight behavior of E schultzei,or on their positions within *** findings suggest rainfall is not a serious hazard for *** thrips can survive raindrop collisions during flight,as impacts with water droplets are not expected to break the surface tension.

关键词： barometric pressure Frankliniella schultzei Malvaviscus arboreus rainfall shelter thrips

Atomistic simulations of friction at an ice−ice interface

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Friction 2013年第3期1卷 242-251页

作者： N.SAMADASHVILI B.REISCHL T.HYNNINEN T.ALA-NISSILÄ A.S.foster COMP Centre of Excellence Aalto University School of ScienceDepartment of Applied PhysicsP.O.Box 11100FI-00076 AaltoFinland Department of Physics Tampere University of TechnologyP.O.Box 692FI-33101 TampereFinland

Even though the slipperiness of ice is important both technologically and environmentally and often experienced in everyday life,the nanoscale processes determining ice friction are still *** study the friction of a smooth ice-ice interface using atomistic simulations,and especially consider the effects of temperature,load,and sliding *** this scale,frictional behavior is seen to be determined by the lubricating effect of a liquid premelt layer between the sliding ice *** general,increasing temperature or load leads to a thicker lubricating layer and lower friction,while increasing the sliding velocity increases friction due to viscous shear.

关键词： ice friction nanoscale molecular dynamics TIP4P/ice

IT-Software SMEs in China, Technology Transfer from Universities and Entrepreneurship, a Successful Nexus？

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Frontiers of Business Research in China 2014年第1期8卷 18-48页

作者： Jianghong Cao M. John foster Lorraine Watkins-Mathys Kingston-Business School Kingston University Kingston Upon Thames KT2 7LB UK

Drawing on the empirical work of a broader study, this paper examines whether technology is being successfully transferred from universities to the IT-sottware SMEs present in China, and the effectiveness of entrepreneurship in effecting such transfers. A conceptual framework was generated to guide the investigation. Data were elicited using a detailed questionnaire which generated 53 usable responses; follow-up interviews with 17 of the 53 respondents; and four interviews with relevant government officials （civil servants from the Ministry of Science and Technology and state-owned banks）. There were three main fmdings. Chinese software SMEs tend to be reluctant to adopt new technologies from local tmiversities; there is a lack of common purpose between the parties; and entrepreneurs who did undertake such technology transfer felt the process was badly impeded by the lack of available finance, and expressed fears about poor protection of intellectual property rights in China. The majority of the sample firms acted opportunistically, taking advantage of the benefits offered under government schemes to earn rapid returns mainly using extant technologies. These conclusions suggest that the Chinese government＇s policies in this area of technology transfer have had only limited success.

关键词： entrepreneurship technology transfer universities IT-software,SME China

Demographics and Population Dynamics Project the Future of Hard Coral Assemblages in Little Cayman

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Open Journal of Marine Science 2018年第1期8卷 196-213页

作者： Kristi A. foster Greg foster Coastal & Marine Ecology Consultants Inc. Nehalem OR USA

Individual hard coral colonies from four representative reef sites around Little Cayman were surveyed yearly between 2010 and 2015, a period of non-disturbance between two elevated seawater temperature anomalies. Photographic censuses produced 7069 annual transitions that were used to describe the demographics (size class frequencies, abundance, area cover) and population dynamics under non-disturbance environmental conditions. Agariciids, Porites asteroides, and Siderastrea radians have replaced acroporids as the predominant massive corals. Recruitment rates were generally low (150 cm2 surface areas, live area cover may remain relatively stable. Projection models indicated that downward population trends would be exacerbated even by mild disturbance (5% - 10% mortality) scenarios. The fate of hard corals on Little Cayman’s reefs was determined to be heavily dependent on the health and transitions of agariciid colonies. Conservation strategies that currently focus on restoration of Caribbean acroporids should be expanded to include agariciids, which were previously considered “weeds”.

关键词： Caribbean Coral Size Class Transitions Vital Rates Recovery Projections Little Cayman

Smaller and bolder prey snails have higher survival in staged encounters with the sea star Pisaster giganteus

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Current Zoology 2017年第6期63卷 633-638页

作者： William C. foster Connor M. ARMSTRONG Gregory T. CHISM Jonathan N. PRUITT Department of Ecology Evolution and Marine Biology University of California Santa Barbara Santa Barbara CA93180 USA

Temporally consistent individual differences in behavior, also known as animal personality, can have large impacts on individual fitness. Here, we explore the degree to which individual differences in anti-predator response (or boldness) influence survival rates in groups of snails when they encounter a predatory sea star . The snail shows consistent individual variation in predator response where some fearful snails actively flee bodies of water occupied by predators whereas bolder snails consistently do not. We show here that bold snails are significantly more likely to survive encounters with a predatory sea star and, somewhat counterintuitively, fearful snails actually suffer higher mortality rates. We also found that smaller snails and those occurring at higher experimental densities experienced higher per capita survival rates. Positive effects of prey boldness on survival are not uncommonly reported in the animal personality literature; however, such results are inconsistent with classic animal personality theory borrowed from the optimal foraging literature. The findings herein add to the growing body of evidence that consistent individual differences in behavior can impact predator-prey interactions and that boldness is potentially under positive predator-driven selection in some systems.

关键词： behavioral syndrome behavioral type personality predation risk survival selection temperament