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End-to-End Rate Adaptation to Support Heterogeneous Services for Infrastructure-Based Vehicular Netw.rks

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ZTE Communications 2014年第1期12卷 3-10页

作者： Yuanguo Bi Hangguan Shan Xuemin (sherman) Shen Hai Zhao College of Information Science and Engineering Northeastern University Institute of Information and Communication Engineering Zhejiang University Department of Electrical and Computer Engineering University of Waterloo

Vehicle to Infrastructure （V2I） communications aim to provide mobile users on the road low.cost Internet and driver safety services. How.ver, to meet Quality of Service （QoS） requirements of various applications and officiently utilize limited w.reless channel resourc- es, the transport layer protocol has to perform effective rate control in low.channel quality and frequent changing topology communica- tion environment. In this paper, w. propose a novel rate-control scheme in infrastructure based vehicular netw.rks that avoids conges- tion and starvation and promotes fairness in end-to-end V2I communications. In vehicular netw.rks, a bottleneck roadside unit （RSU） keeps track of its buffer size, aggregate incoming rate, and link throughput, and appropriately allocates bandw.dth to traversing flow.. w.th feedback information from the RSU, source nodes dynamically adjust their sending rates to avoid buffer overflow.or starvation at the bottleneck RSU. Simulation results show.that the proposed scheme can reduce not only packet losses ow.ng to buffer overflow.but also buffer starvation time, w.ich improves the utilization efficiency of w.reless channel resource.

关键词： vehicle to infrastructure communications roadside unit congestion avoidance starvation avoidance transport layer

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Changes in soil free-living nematode communities and their trophic composition along a climatic gradient

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Open Journal of Ecology 2012年第2期2卷 79-89页

作者： Tal Levi Chen sherman Stanislav Pen-Mouratov Yosef Steinberger The Mina & Everard Goodman Faculty of Life Sciences Bar-Ilan University Ramat-Gan Israel

Ambiguity exists concerning the effects of climate on soil nematode-community composition. In this study, w. examined the free-living nematode communities in soil along a climatic gradient representing humid-Mediterranean, Mediterranean, semi-arid, and arid climate types. The relationships betw.en abiotic soil characteristics (organic carbon, soil moisture (SM), w.ter-holding capacity) and nematode parameters, such as abundance, trophic group composition, and diversity indices, w.re explored in the context of climate and seasonality. Nematode abundance w.s low.st at the arid site. At the humid Mediterranean and Mediterranean locations, nematode abundance reached its peak in w.nter, w.ile at the semi-arid and arid sites, an almost opposite trend w.s observed, w.th low.st abundances in w.nter, presumably due to a nutrient w.shout from the soil profile during the rainy season. On the trophic level, one trophic group demonstrated a positive correlation w.th SM and one trophic group demonstrated a negative one at each location, w.ile the other tw. groups remained constant. Fungi-feeding nematodes w.re found to be unaffected by SM at the humid-Mediterranean and Mediterranean locations, w.ile at the semi-arid and arid sites their proportion increased in correlation w.th decreasing SM. Bacteria-feeders increased w.th SM at the arid site, w.re unaffected at the semi-arid location, and decreased w.th SM at the humid-Mediterranean and Mediterranean sites. Plant-parasites w.re associated w.th SM only at the humid-Mediterranean site. Omnivores-predators w.re positively affected by SM at the tw. middle locations, staying constant at the humid-Mediterranean and arid sites. These findings point to the strong linkage existing betw.en nematode trophic behavior and climatic factors, demonstrating distinctive communal fingerprints for each climate type.

关键词： Climate Gradient Diversity Soil Nematode Trophic Group

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Lange Q & A.

2012年

作者： Carolan. sherman Mary Chmielew.ki

ISBN: (纸本)9780071745765

Machine generated contents note: Part 1 Fundamental Know.edge 1. Terminology 2. Anatomy and Physiology 3. Microbiology 4. Pharmacology and Anesthesia Part 2 Infection Control 5. Aseptic Technique 6. Sterilization and Disinfection 7. Operating Room Environment Part 3 Concepts of Patient Care 8. Transportation and Positioning 9. Observation 10. Cardiopulmonary Resuscitation 11. Medical Ethical and L

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为冬季温暖地区选育需冷量低的桃和油桃品种

国外农学（果树） 1989年第2期 27-29页

作者： sherman w.B. 夏英华

本文对需冷量低的桃和油桃的育种工作和无性系试验进行了评述,指出了关于这一工作已完成的部分和待达到的项定目标之详细内容。开发需冷量低的桃和油桃种质的佛罗里达品种改良计划,在世界上是唯一的,品种和选择的无性系正在冬季温暖地区... 详细信息

本文对需冷量低的桃和油桃的育种工作和无性系试验进行了评述,指出了关于这一工作已完成的部分和待达到的项定目标之详细内容。开发需冷量低的桃和油桃种质的佛罗里达品种改良计划,在世界上是唯一的,品种和选择的无性系正在冬季温暖地区的60多个国家进行广泛试验,有10个国家用佛州需冷量低的品种进行有效的大规模生产。在各种纬度、海拔高度和小气候条件下对这些需冷量低的品种及其适应性已进行了评价。

关键词：桃油桃品种选育低需冷量

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Reconfigurable intelligent surfaces for smart w.reless environments: channel estimation, system design and applications in 6G netw.rks

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Science China(Information Sciences) 2021年第10期64卷 52-72页

作者： Ying-Chang LIANG Jie CHEN Ruizhe LONG Zhen-Qing HE Xianqi LIN Chenlu HUANG Shilin LIU Xuemin (sherman) SHEN Marco DI RENZO Center for Intelligent Netw.rking and Communications University of Electronic Science and Technology of China School of Electronic Science and Engineering University of Electronic Science and Technology of China Department of Electrical and Computer Engineering University of Waterloo Université Paris-Saclay CNRS CentraleSupélec Laboratoire des Signaux et Systèmes

Reconfigurable intelligent surface(RIS), one of the key enablers for the sixth-generation(6G)mobile communication netw.rks, is considered by designers to smartly reconfigure the w.reless propagation environment in a controllable and programmable manner. Specifically, an RIS consists of a large number of low.cost and passive reflective elements(REs) w.thout radio frequency chains. The system gain of RIS w.reless systems can be achieved by adjusting the phase shifts and amplitudes of the REs so that the desired signals can be added constructively at the receiver. How.ver, an RIS typically has limited signal processing capability and cannot perform active transmitting/receiving in general, w.ich leads to new.challenges in the physical layer design of RIS w.reless systems. In this paper, w. provide an overview.of the RIS-aided w.reless systems, including the reflection principle, channel estimation, and system design. In particular,tw. types of emerging RIS systems are considered: RIS-aided w.reless communications(RAw.) and RISbased information transmission(RBIT), w.ere the RIS plays the role of the reflector and the transmitter,respectively. w. also envision the potential applications of RIS in 6G netw.rks.

关键词： reconfigurable intelligent surface channel estimation RIS-aided w.reless communications RIS-based information transmission 6G

The Digital Age of Campus Maps on Mobile Devices

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Journal of Computer and Communications 2016年第7期4卷 22-30页

作者： Fan w. Dw.yne Clarke Jian Jiang Asif Baba sherman Buford Computer Science Department Tuskegee University Tuskegee USA Police Department Tuskegee University Tuskegee USA

Developing mobile applications have alw.ys been a rising topic in the technology w.rld. w.th the recent development in technology, mobile applications play an important role in various applications throughout the w.rld. Mobile applications are constantly evolving. There are several ongoing research and developments in both industry and academia. In this paper, w. present the design and implementation of a mobile application that creates an electronic map or e-map application for the campus of Tuskegee University. The goals for this mobile application are to make the campus map easier and user-friendly for parents, visitors, and students using mobile devices. w.th this mobile application, the users w.ll be able to search and find campus buildings, as w.ll as give feedback on the application to eliminate the need for paper documentation.

关键词： Mobile Application Mobile Device E-Map

榴菌素产生菌紫红链霉菌Tü22的多聚乙酰合成酶基因簇的结构和功能

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国外医药（抗生素分册） 1991年第1期12卷 1-4页

作者： David H.sherman 余柏松

多聚乙酰(polyketide)类组成了一大系列由细菌(主要是放线菌)、真菌和植物产生的各种结构的复杂次级代谢物,其中大部分已证明是人用和兽用药品,在畜牧业则作为治疗用抗生素,化疗药物和生长刺激剂,还有一些较为重要的是真菌黄曲霉毒素,... 详细信息

多聚乙酰(polyketide)类组成了一大系列由细菌(主要是放线菌)、真菌和植物产生的各种结构的复杂次级代谢物,其中大部分已证明是人用和兽用药品,在畜牧业则作为治疗用抗生素,化疗药物和生长刺激剂,还有一些较为重要的是真菌黄曲霉毒素,植物色素或香味物质。多聚乙酰的生物合成似乎类似于长链脂肪酸的生物合成。这种脂肪酸的生物合成是由以下反应重复循环进行的,即丙二酰基辅酶 A 衍生的二碳单位(乙酸残基)。

关键词：多聚乙酰合成酶结构功能抗生素

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