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Tasks Scheduling in Cloud Environment Using PSO-BATS with MLRHE
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作者 Anwar R Shaheen Sundar Santhosh Kumar 《Intelligent Automation & Soft Computing》 SCIE 2023年第3期2963-2978,共16页
Cloud computing plays a significant role in Information Technology(IT)industry to deliver scalable resources as a service.One of the most important factor to increase the performance of the cloud server is maximizing t... Cloud computing plays a significant role in Information Technology(IT)industry to deliver scalable resources as a service.One of the most important factor to increase the performance of the cloud server is maximizing the resource utilization in task scheduling.The main advantage of this scheduling is to max-imize the performance and minimize the time loss.Various researchers examined numerous scheduling methods to achieve Quality of Service(QoS)and to reduce execution time.However,it had disadvantages in terms of low throughput and high response time.Hence,this study aimed to schedule the task efficiently and to eliminate the faults in scheduling the tasks to the Virtual Machines(VMs).For this purpose,the research proposed novel Particle Swarm Optimization-Bandwidth Aware divisible Task(PSO-BATS)scheduling with Multi-Layered Regression Host Employment(MLRHE)to sort out the issues of task scheduling and ease the scheduling operation by load balancing.The proposed efficient sche-duling provides benefits to both cloud users and servers.The performance evalua-tion is undertaken with respect to cost,Performance Improvement Rate(PIR)and makespan which revealed the efficiency of the proposed method.Additionally,comparative analysis is undertaken which confirmed the performance of the intro-duced system than conventional system for scheduling tasks with highflexibility. 展开更多
关键词 Task scheduling virtual machines(VM) particle swarm optimization(PSO) bandwidth aware divisible task scheduling(bats) multi-layered regression
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MM5BATS对东亚夏季气候及其变化的模拟试验 被引量:6
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作者 汤剑平 赵鸣 +1 位作者 苏炳凯 赵得明 《高原气象》 CSCD 北大核心 2005年第1期28-37,共10页
将陆面过程模式BATS耦合到中尺度模式 MM5V3 中与另一区域气候模式 RegCM2 一起对1995-2000年夏季东亚的区域气候作了模拟试验, 并与实际资料作了比较。模拟试验结果表明: (1)两个模式均能较合理地模拟出6年夏季平均的环流、温度和海平... 将陆面过程模式BATS耦合到中尺度模式 MM5V3 中与另一区域气候模式 RegCM2 一起对1995-2000年夏季东亚的区域气候作了模拟试验, 并与实际资料作了比较。模拟试验结果表明: (1)两个模式均能较合理地模拟出6年夏季平均的环流、温度和海平面气压等的变化, MM5BATS的模拟结果要略优于RegCM2的结果; (2)MM5BATS模式较合理地模拟出了 6 年夏季平均的降水分布, 而RegCM2模式的模拟结果偏强; (3)MM5BATS模式较好地模拟出了 1997 年和 1998 年夏季环流场的变化, 对降水的模拟也比较合理。RegCM2对1997年和 1998 年降水的模拟基本上都偏强。模拟试验结果还表明, 在区域气候模拟中有必要采用更新的模式。 展开更多
关键词 MM5bats 区域气候模式 陆面过程
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用 BATS 模型模拟径流的个例研究 被引量:4
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作者 刘春蓁 程斌 +1 位作者 程兴无 章四龙 《水文》 CSCD 北大核心 1998年第1期8-13,共6页
为了解陆气间水热交换在径流形成中的作用,本文采用BATS模型模拟了淮河流域山区和平原在1991年汛期50天的暴雨洪水过程,计算了径流,土壤温度和感热,潜热通量,并用常规的汇流计算方法得到了流域出口断面的流量过程线。为... 为了解陆气间水热交换在径流形成中的作用,本文采用BATS模型模拟了淮河流域山区和平原在1991年汛期50天的暴雨洪水过程,计算了径流,土壤温度和感热,潜热通量,并用常规的汇流计算方法得到了流域出口断面的流量过程线。为了集总地考虑地形(山区及平原)对径流的影响,对径流表达式中的指数“n”进行了修正。计算结果表明:50天洪水总量计算误差较小,模拟洪水的洪峰流量与峰现时间与实况相近,径流值的模拟精度与土壤表层温度的模拟精度紧密相关。所有这些说明径流模拟精度的提高是改进陆面对大气的感热、潜热通量计算的一个重要方面。 展开更多
关键词 bats模型 陆气水热交换 径流模拟 河流
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陆面过程模式BATS中地气通量计算方案的一个改进试验 被引量:2
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作者 陈潜 赵鸣 +1 位作者 汤剑平 苏炳凯 《南京大学学报(自然科学版)》 CAS CSCD 北大核心 2004年第3期330-340,共11页
 在原有的陆面过程模式BATS中,对地表通量的计算基于简单的经验公式,这个计算是十分粗略的.而地气通量对各个气象要素的模拟都很重要,如动量通量会影响大气中的风速分布,热量通量会影响垂直方向上的温度分布而改变大气的层结稳定度,水...  在原有的陆面过程模式BATS中,对地表通量的计算基于简单的经验公式,这个计算是十分粗略的.而地气通量对各个气象要素的模拟都很重要,如动量通量会影响大气中的风速分布,热量通量会影响垂直方向上的温度分布而改变大气的层结稳定度,水汽通量则会改变空气中的水分含量和潜热,因而改进地气通量的计算精度是有必要的.为了提高地─气间通量计算的精度,在模式中增加稳定度的分类,将近地层稳定度分为5类,用中尺度气候模式RIEMS,分别对短期和中期模拟作了对比实验.经过比较和分析模拟结果,可以看出在增加稳定度的分类以后,模拟的各个气象要素场都较原来的有了改善. 展开更多
关键词 bats 稳定度 中尺度气候模式 地气通量 陆面过程模式
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陆面过程模型CoLM与BATS1e的模拟精度比较——以东北玉米农田为例 被引量:1
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作者 蔡福 明惠青 +2 位作者 米娜 李荣平 张玉书 《地理科学》 CSCD 北大核心 2014年第6期740-747,共8页
利用2008年锦州玉米农田生态系统野外观测站资料对CoLM与BATS1e模型模拟能力进行定量评价。比较发现:两模型对净辐射和表层土壤温度的模拟精度都较高且差异不大,CoLM模型对感热、潜热、土壤热通量、次表层土壤温度模拟能力都不同程度高... 利用2008年锦州玉米农田生态系统野外观测站资料对CoLM与BATS1e模型模拟能力进行定量评价。比较发现:两模型对净辐射和表层土壤温度的模拟精度都较高且差异不大,CoLM模型对感热、潜热、土壤热通量、次表层土壤温度模拟能力都不同程度高于BATS1e模型,模拟值对实测值解释能力分别偏高3%、22%、1%、10%,NS(Nash-sutcliffe效率系数)分别偏高1.042、0.266、0.023、0.138。从各月情况看,两模型在7月对感热、潜热模拟能力都较高,而在其它月份CoLM模型模拟精度明显高于BATS1e模型,土壤热通量和次表层土壤温度在5~8月前者模拟精度高于后者。由于CoLM模型对潜热更高精度的模拟可证明其对表层土壤湿度模拟精度高于BATS1e模型。 展开更多
关键词 CoLM模型 bats1e模型 东北玉米农田 模拟精度比较
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基于高斯消元的BATS码的改进译码算法
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作者 杨娟 嵇建波 李海兵 《通信技术》 2020年第2期268-272,共5页
BATS码是一种包括外码和内码的纠删码,外码是喷泉码的矩阵形式。内码是网络编码结构,采用随机线性网络编码算法。BATS码的常用译码算法为BP译码算法,但对有限长BATS码,BP译码算法的性能有大幅度的衰减。因此,在计算资源充足的情况下,可... BATS码是一种包括外码和内码的纠删码,外码是喷泉码的矩阵形式。内码是网络编码结构,采用随机线性网络编码算法。BATS码的常用译码算法为BP译码算法,但对有限长BATS码,BP译码算法的性能有大幅度的衰减。因此,在计算资源充足的情况下,可以在BP译码器后采用高斯消元算法对BATS码进行译码。采用高斯消元算法时,矩阵满秩则输入数据包可译,反之则不可译。因此,利用当矩阵不满秩时也有部分包可译的特点,识别并将这部分可译包译出,从而提高高斯消元译码器的译码性能。 展开更多
关键词 bats BP译码 高斯消元算法 译码性能
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基于滑窗BATS码的低时延图像渐进传输方案设计
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作者 史治平 黄文才 +1 位作者 王臣玺 罗萱 《电子科技大学学报》 EI CAS CSCD 北大核心 2021年第4期496-501,共6页
在图像通信中,为了节约网络资源同时保证在多跳网络中的可靠传输,该文提出了一种基于编码统计的滑窗BATS码和小波SPIHT编码的图像传输方案。该方案同基于传统BATS码和SPIHT编码的图像传输方案、基于普通滑窗BATS码和SPIHT编码的图像传... 在图像通信中,为了节约网络资源同时保证在多跳网络中的可靠传输,该文提出了一种基于编码统计的滑窗BATS码和小波SPIHT编码的图像传输方案。该方案同基于传统BATS码和SPIHT编码的图像传输方案、基于普通滑窗BATS码和SPIHT编码的图像传输方案相比,不仅较好地改善了BATS码的编码随机性对传输可靠性的影响,还在保证方案具备渐进传输特性的同时显著地降低了传输时延,从而提高了图像通信的用户体验质量(QoE)。 展开更多
关键词 bats 图像传输 用户体验质量 小波SPIHT编码
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Discuss of Key Issue for Automatic BATS Control in Regional Power Grid
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作者 Kaiyan Pan Yingying Sun Zhenyan Gao 《Energy and Power Engineering》 2017年第4期189-197,共9页
Busbar Automatic Transfer Switch (BATS) is very important for power distribution reliability. However, BATS can’t consider whether it cause overloading of devices after it acts. In this paper, we introduce the design... Busbar Automatic Transfer Switch (BATS) is very important for power distribution reliability. However, BATS can’t consider whether it cause overloading of devices after it acts. In this paper, we introduce the design principle of Automatic BATS control from whole architecture including its function, strategy and a rule of on-off. On the other hand, the running experience and effect is also introduced. Site operation shows that the proposed method is feasible and it can ensure power grid reliability. 展开更多
关键词 BUSBAR AUTOMATIC Transfer SWITCH (bats) N Minus One ON-LINE Controlling Automaitc bats CONTROL
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Land-Air Interaction over Arid/Semi-arid Areas in China and Its Impact on the East Asian Summer Monsoon. Part I:Calibration of the Land Surface Model (BATS)Using Multicriteria Methods 被引量:14
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作者 陈文 朱德琴 +1 位作者 刘辉志 孙菽芬 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2009年第6期1088-1098,共11页
To improve the land surface simulation in the arid and semi-arid areas of northern China, the observational data from two field experiments in Dunhuang and Tongyu are used to optimize the parameters in the land surfac... To improve the land surface simulation in the arid and semi-arid areas of northern China, the observational data from two field experiments in Dunhuang and Tongyu are used to optimize the parameters in the land surface model, BATS, through calibration with the multicriteria method. Sensitivity analysis to the parameters in Dunhuang and Tongyu indicates that different parameters need to be calibrated in two sites with different environmental and climate regimes. Comparison of observed sensible heat flux, latent heat flux, and ground surface temperature with the simulated ones shows the simulations with the optimized parameters have been substantially improved. Especially, the holistic simulations with the calibration of the parameter values are much closer to the observations in the arid region (Dunhuang), and the energy partition with the calibrated parameters can also be simulated well in the semi-arid region (Tongyu). Whole results demonstrate that the parameter calibration of the land surface model is important when the model is to be used to investigate the land-air interaction. 展开更多
关键词 land-air interaction the arid and semi-arid areas bats multicriteria method
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空间通信与BATS码:天成之合(英文) 被引量:1
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作者 杨伟豪 董光亮 +3 位作者 朱键 李海涛 杨升浩 陈超 《深空探测学报》 2018年第2期129-139,共11页
创新通信技术在国家重大空间技术开发计划中有着巨大的需求。本文综述了基于网络编码的空间通信技术,旨在探索未来基于网络编码的空间通信技术的可行性和潜力。首先讨论了空间通信的特点,并给出了不同编码方法的概述;详细介绍了基于网... 创新通信技术在国家重大空间技术开发计划中有着巨大的需求。本文综述了基于网络编码的空间通信技术,旨在探索未来基于网络编码的空间通信技术的可行性和潜力。首先讨论了空间通信的特点,并给出了不同编码方法的概述;详细介绍了基于网络编码的批量稀疏编码(BATS码)创新技术。BATS码作为一种潜在的应用技术可以很好地解决多跳中继网络中严重丢包问题;给出一个BATS码原型设计和实现,实验结果证明BATS码比现有技术具有明显优势;最后,讨论了BATS码在空间通信中的应用前景。 展开更多
关键词 空间通信 丢包 网络编码 bats
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空间通信中的一种滑动窗口BATS码传输方案研究
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作者 曾柯 刘晓东 +2 位作者 卓永宁 吕梦昭 王思 《载人航天》 CSCD 北大核心 2019年第4期518-524,共7页
针对空间通信中链路传播时延大、丢包率高、中继节点多的问题,在具有良好多级中继传输性能的BATS码基础上,提出一种滑动窗口传输方案,以提高空间传输的可靠性和时效性。利用小度值Batch对滑动窗口的非重叠区域进行编码传输,并采用不等... 针对空间通信中链路传播时延大、丢包率高、中继节点多的问题,在具有良好多级中继传输性能的BATS码基础上,提出一种滑动窗口传输方案,以提高空间传输的可靠性和时效性。利用小度值Batch对滑动窗口的非重叠区域进行编码传输,并采用不等滑动步长,实现了对滑动窗口的重叠部分和非重叠部分的均衡保护,使传输既具有较高可靠性,又具有较高的传输效率。仿真结果表明,在维持与传统的连续重叠滑窗相近可靠性的同时,传输效率提高约20%。 展开更多
关键词 bats 网络编码 滑动窗口 空间通信
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基于重要信息反馈的BATS码优化设计
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作者 杨娟 史治平 嵇建波 《电子科技大学学报》 EI CAS CSCD 北大核心 2022年第2期194-199,共6页
BATS码是一种结合喷泉码和网络编码技术的新型前向纠删码,能有效保证数据在多跳网络中的可靠传输。在传统BATS码编译码方案中,反馈信息没有得到高效利用,为提高BATS码的译码性能,提出了一种改进的基于重要信息反馈的BATS码编译码算法,其... BATS码是一种结合喷泉码和网络编码技术的新型前向纠删码,能有效保证数据在多跳网络中的可靠传输。在传统BATS码编译码方案中,反馈信息没有得到高效利用,为提高BATS码的译码性能,提出了一种改进的基于重要信息反馈的BATS码编译码算法,其中,重要信息包由接收端和发送端共同选择用于下一轮编码;同时,对重要信息的编码包在中继节点采用网络编码算法进行再编码,以保证重要信息在接收端的可靠恢复。仿真结果表明,该方案相比传统的BATS码以及过去用于喷泉码的基于重要信息反馈的编译码方案,具有更好的译码性能。 展开更多
关键词 bats BP译码算法 反馈 文件分发
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伽玛射线暴源的新分布:BATSE的观测结果 被引量:2
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作者 徐达维 史天一 《天文学进展》 CSCD 北大核心 1995年第1期30-38,共9页
介绍了康普顿γ射线天文台上BATSE有关暴源分布观测的新发现。这一发现对80年代以前所普遍接受的γ射线暴起源于银盘内中子星的模型提出了严重挑战,并阐明了几种以BATSE结果为基础的暴源分布模型。
关键词 Γ射线源 暴源 宇宙飞行器 batsE
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Preface: Aerodynamics, dynamics and control of animal(insects, birds and bats) flight
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作者 Sun Mao 《Acta Mechanica Sinica》 SCIE EI CAS CSCD 2014年第6期775-775,共1页
Animal flight and swimming have long been of great interest to people.Besides curiosity about how their sophisticated aero-and hydrodynamic feats are performed,researches are very interested in the mechanics of animal... Animal flight and swimming have long been of great interest to people.Besides curiosity about how their sophisticated aero-and hydrodynamic feats are performed,researches are very interested in the mechanics of animal flight and swimming for the following two reasons.One is that biologists need to understand the effects of aero-and hydrodynamic force production and energy expenditure on the physiology,behavior,evolution and other aspects of the animals.The 展开更多
关键词 INSECTS AERODYNAMICS PREFACE birds and bats dynamics and control of animal
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Unexpected expression of heat-activated transient receptor potential(TRP)channels in winter torpid bats and cold-activated TRP channels in summer active bats
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作者 Yang-Yang Li Qing-Yun Lv +7 位作者 Guan-Tao Zheng Di Liu Ji Ma Gui-Mei He Li-Biao Zhang Shan Zheng Hai-Peng Li Yi-Hsuan Pan 《Zoological Research》 SCIE CAS CSCD 2022年第1期52-63,共12页
The ability to sense temperature changes is crucial for mammalian survival.Mammalian thermal sensing is primarily carried out by thermosensitive transient receptor potential channels(Thermo-TRPs).Some mammals hibernat... The ability to sense temperature changes is crucial for mammalian survival.Mammalian thermal sensing is primarily carried out by thermosensitive transient receptor potential channels(Thermo-TRPs).Some mammals hibernate to survive cold winter conditions,during which time their body temperature fluctuates dramatically.However,the underlying mechanisms by which these mammals regulate thermal responses remain unclear.Using quantitative real-time polymerase chain reaction(qRT-PCR)and the Western blotting,we found that Myotis ricketti bats had high levels of heat-activated TRPs(e.g.,TRPV1 and TRPV4)during torpor in winter and cold-activated TRPs(e.g.,TRPM8 and TRPC5)during active states in summer.We also found that laboratory mice had high mRNA levels of cold-activated TRPs(e.g.,Trpm8 and Trpc5)under relatively hot conditions(i.e.,40°C).These data suggest that small mammals up-regulate the expression of cold-activated TRPs even under warm or hot conditions.Binding site analysis showed that some homeobox(HOX)transcription factors(TFs)regulate the expression of hot-and cold-activated TRP genes and that some TFs of the Pit-Oct-Unc(POU)family regulate warm-sensitive and cold-activated TRP genes.The dual-luciferase reporter assay results demonstrated that TFs HOXA9,POU3F1,and POU5F1 regulate TRPC5 expression,suggesting that Thermo-TRP genes are regulated by multiple TFs of the HOX and POU families at different levels.This study provides insights into the adaptive mechanisms underlying thermal sensing used by bats to survive hibernation. 展开更多
关键词 HIBERNATION bats Brain Thermo-TRPs
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Effects of historic wildfire and prescribed fire on site occupancy of bats in Shenandoah National Park,Virginia,USA
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作者 Lauren V.Austin Alexander Silvis +1 位作者 W.Mark Ford Karen E.Powers 《Journal of Forestry Research》 SCIE CAS CSCD 2020年第4期1255-1270,共16页
Given the likelihood of regional extirpation of several once-common bat species in eastern North America from white-nose syndrome,it is critical that the impacts of forest management activities,such as prescribed fire... Given the likelihood of regional extirpation of several once-common bat species in eastern North America from white-nose syndrome,it is critical that the impacts of forest management activities,such as prescribed fire,are known in order to minimize potentially additive negative effects on bat populations.Historic wildfires may offer a suitable surrogate to assess long-term burn impacts on bats for planning,implementing and assessing burn programs.To examine the effects of historic fire on bats,we sampled bat activities at 24 transect locations in burned and unburned forest stands in the central Appalachian Mountains of Shenandoah National Park(SNP),Virginia,USA.There was limited evidence of positive fire effects over time on hoary bats(Lasiurus cinereus Beauvois)and big brown bats(Eptesicus fuscus Beauvois)occupancy.Overall,there were few or mostly equivocal relationships of bat occupancy relative to burn conditions or time since fire in SNP across species using a false-positive occupancy approach.Our results suggest that fire does not strongly affect bat site occupancy short-or long-term in the central Appalachians. 展开更多
关键词 Appalachian mountains bats False-positive occupancy Prescribed fire WILDFIRE
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Ecological study of cave nectar bats reveals low risk of direct transmission of bat viruses to humans
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作者 Kai Zhao Wei Zhang +9 位作者 Bei Li Shi-Zhe Xie Fan Yi Ren-Di Jiang Yun Luo Xiang-Yang He Yun-Zhi Zhang Zheng-Li Shi Li-Biao Zhang Xing-Lou Yang 《Zoological Research》 SCIE CAS CSCD 2022年第4期514-522,共9页
Bats are reservoirs of various viruses.The widely distributed cave nectar bat(Eonycteris spelaea)is known to carry both filoviruses and coronaviruses.However,the potential transmission of theses bat viruses to humans ... Bats are reservoirs of various viruses.The widely distributed cave nectar bat(Eonycteris spelaea)is known to carry both filoviruses and coronaviruses.However,the potential transmission of theses bat viruses to humans is not fully understood.In this study,we tracked 16 E.spelaea bats in Mengla County,Yunnan Province,China,using miniaturized GPS devices to investigate their movements and potential contact with humans.Furthermore,to determine the prevalence of coronavirus and filovirus infections,we screened for the nucleic acids of the Měnglàvirus(MLAV)and two coronaviruses(GCCDC1-CoV and HKU9-CoV)in anal swab samples taken from bats and for antibodies against these viruses in human serum samples.None of the serum samples were found to contain antibodies against the bat viruses.The GPS tracking results showed that the bats did not fly during the daytime and rarely flew to residential areas.The foraging range of individual bats also varied,with a mean cumulative nightly flight distance of 25.50 km and flight speed of up to 57.4 km/h.Taken together,these results suggest that the risk of direct transmission of GCCDC1-CoV,HKU9-CoV,and MLAV from E.spelaea bats to humans is very low under natural conditions. 展开更多
关键词 bats Eonycteris spelaea GPS tracking GCCDC1-CoV HKU9-CoV Měnglàvirus
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Vampire Bats
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作者 晓英 《语言教育》 1993年第6期35-38,共4页
On a moonless,starless night the vampires come outto hunt for food.The faces of their victims twist as theystruggle in pain,their teeth changing shape as they them-
关键词 night teeth IMAGINATION REALLY GETTING themselves TWIST Vampire bats TONGUE ANYTHING
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农业科技通讯(BATS)2019年第1~12期年度目次索引
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《农业科技通讯》 2019年第12期327-343,共17页
关键词 玉米新品种 种植表现 小麦新品种 高产栽培技术 bats)2019 农业科技通讯
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农业科技通讯(BATS)2006年第1-12期年度目次索引
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《农业科技通讯》 2006年第12期62-68,共7页
关键词 高产栽培技术 玉米新品种 bats)2006 水稻新品种 栽培技术要点 小麦新品种 玉米杂交种 无公害生产 无公害栽培技术 特征特性 杂交棉 杂交稻 水稻 夏大豆 夏作大豆 农业 科技通讯 目次索引
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