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改性聚苯醚吸收法测定高分子食品接触材料高温下全迁移物析出量 被引量:2
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作者 宋帝 万杰 程刚 《检验检疫学刊》 2011年第3期26-28,59,共4页
建立了改性聚苯醚吸收法测定食品接触材料高温下全迁移物析出量的方法,并对取样方法、提取溶剂、吸附物净化、加热温度、提取周期以及系统稳定性进行讨论。本方法RSD为2.3%-2.6%(n=10),具有操作简单、快速等特点。能够满足对食品接触材... 建立了改性聚苯醚吸收法测定食品接触材料高温下全迁移物析出量的方法,并对取样方法、提取溶剂、吸附物净化、加热温度、提取周期以及系统稳定性进行讨论。本方法RSD为2.3%-2.6%(n=10),具有操作简单、快速等特点。能够满足对食品接触材料高温下全迁移物析出量的分析要求。 展开更多
关键词 全迁移物析出量 食品接触材料 高温 改性聚苯醚
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虚拟机快速全系统在线迁移 被引量:5
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作者 张翔 霍志刚 +1 位作者 马捷 孟丹 《计算机研究与发展》 EI CSCD 北大核心 2012年第3期661-668,共8页
虚拟机全系统在线迁移对于广域网或者没有共享存储的局域网中的虚拟化平台非常重要.然而,全系统映像一般在几十吉字节(gigabyte,GB)量级,迁移这些数据需占用大量I/O带宽且时间开销很大.快速全系统在线迁移方法具有如下特点:文件系统感... 虚拟机全系统在线迁移对于广域网或者没有共享存储的局域网中的虚拟化平台非常重要.然而,全系统映像一般在几十吉字节(gigabyte,GB)量级,迁移这些数据需占用大量I/O带宽且时间开销很大.快速全系统在线迁移方法具有如下特点:文件系统感知的磁盘同步,利用文件系统的磁盘块分配位图,只拷贝实际使用的磁盘块,显著减少了第1阶段同步的磁盘映像数据量;异或压缩,利用映像数据的自相似性,快速有效地减少了迁移最后两个阶段拷贝的数据量;流水迁移,流水化迁移各个阶段,使得读写映像、压缩解压映像、网络收发各阶段充分并行.实验表明,与传统压缩迁移相比,快速迁移可以减少50%的迁移时间,最好情况和平均情况下,能分别降低21.68%和14.48%的停机时间.在网络带宽受限或虚拟机负载过重等极限条件下,快速迁移同样有效. 展开更多
关键词 虚拟机 系统在线迁移 文件系统感知的磁盘同步 异或压缩 流水迁移
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星载异构计算环境下的能耗优化任务调度 被引量:2
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作者 安建峰 游红俊 +2 位作者 赵伟勋 刘咪咪 张盛兵 《上海航天(中英文)》 CSCD 2021年第4期38-44,共7页
针对航空航天探测等要求高可靠性、强实时性、低功耗的尖端领域,基于新型的异构多核计算平台对全迁移策略的支持,提出了能耗优化的实时任务调度算法。算法主要分为2部分:负载分配和任务调度。负载分配确定每个任务在不同的处理器集群上... 针对航空航天探测等要求高可靠性、强实时性、低功耗的尖端领域,基于新型的异构多核计算平台对全迁移策略的支持,提出了能耗优化的实时任务调度算法。算法主要分为2部分:负载分配和任务调度。负载分配确定每个任务在不同的处理器集群上工作量的分配比例,并对系统的能耗进行优化。任务调度在负载分配的基础上,采用时间片划分的思想对已分配的任务进行合理调度,保证每个任务都能满足系统约束条件。将此算法与现有的SA算法和Hetero-Split算法进行对比,实验结果显示:此算法比Hetero-Split算法在寻求可行性任务调度方案方面相当,但强于SA算法;在能耗比方面,此算法比Hetero-Split算法在系统总能耗方面有大幅度的降低,降低比率约为23%~24%。 展开更多
关键词 二型异构 多核处理器 实时系统 任务调度算法 全迁移
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Motive force of Qinghai-Tibet Plateau moving to east
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作者 YANG Dong-hong YANG Xue-xiang CHEN Dian-you 《Journal of Geoscientific Research in Northeast Asia》 2005年第1期123-125,共3页
A calculation formula on spherical pattern of Qinghai-Tibet plateau moving model is established. Tibet massif moves norward by east in speed of 28 mm/a, Ganshu-Qinghai massif moves to northeast in speed of 15 mm/a, Qo... A calculation formula on spherical pattern of Qinghai-Tibet plateau moving model is established. Tibet massif moves norward by east in speed of 28 mm/a, Ganshu-Qinghai massif moves to northeast in speed of 15 mm/a, Qomolangma Feng moves northward by a few east in speed of 35 -42 mm/a. The low latitude perimeter is longer than the high latitude perimeter. When the Tibet massif moves northward, its latitude perimeter must be contracted and the Tibet massif must move eastward by Cofiolis. Cofiolis force is inertial in earth rotation. It makes the fall body turning to east and the rising block turning westward. In the Northern Hemisphere, it makes the northward body turning to east and the southward block turning to west. This is the reason why the tectonic zones of western Pacific are different from those of eastern Pacific. 展开更多
关键词 Qinghai-Tibet Plateau GPS measurement crustal velocity eastward flow of crustal material
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A PHEMT Based Wideband LNA for Wireless Applications 被引量:2
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作者 Muhammad Saad Khan ZHANG Hongxin +2 位作者 HE Pengfei Sulman Shahzad Rahat Ullah 《China Communications》 SCIE CSCD 2015年第10期108-116,共9页
This work is about the development of a super low noise amplifier with minimum power consumption and high gain for several wireless applications.The amplifier operates at frequency bands of 0.9-2.4 GHz and can be used... This work is about the development of a super low noise amplifier with minimum power consumption and high gain for several wireless applications.The amplifier operates at frequency bands of 0.9-2.4 GHz and can be used in many applications like Wireless local area network(WLAN),WiFi,Bluetooth,ZigBee and Global System for mobile communications(GSM).This new design can be employed for the IEEE 802.15.4 standard in industrial,scientific and medical(ISM) Band.The enhancement mode pseudomorphic high electron mobility transistor PHEMT is used here due to its high linearity,better performance and less noisy operation.The common source inductive degeneration method is employed here to enhance the gain of amplifier.The amplifier produces a gain of more than 17 dB and noise figure of about 0.5 dB.The lower values of S11 and S22 reflect the accuracy of impedance matching network placed at the input and output sides of amplifier.Agilent Advance Design System(ADS) is used for the design and simulation purpose.Further the layout of design is developed on the FR4 substrate. 展开更多
关键词 low noise amplifier phemt advanced design system wireless local area network global positioning system
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Improving the quantification of waterfowl migration with remote sensing and bird tracking 被引量:7
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作者 Yali Si Qinchuan Xin +2 位作者 Herbert H.T.Prins Willem F.de Boer Peng Gong 《Science Bulletin》 SCIE EI CAS CSCD 2015年第23期1984-1993,共10页
Accurately quantifying waterfowl migration patterns is pertinent to monitor ecosystem health and control bird-borne infectious diseases. In this review, we summarize the current understanding of the environmental mech... Accurately quantifying waterfowl migration patterns is pertinent to monitor ecosystem health and control bird-borne infectious diseases. In this review, we summarize the current understanding of the environmental mechanisms that drive waterfowl migration and then investigate the effect of intra- and inter-annual change in food supply and temperature(e.g., climate change) on their migration patterns. Recent advances in remote sensing and animal tracking techniques make it possible to monitor these environmental factors over a wide range of scales and record bird movements in detail. The synergy of these techniques will facilitate substantial progress in our understanding of the environmental drivers of bird migration. We identify prospects for future studies to test existing hypotheses and develop models integrating up-todate knowledge, high-resolution remote sensing data and high-accuracy bird tracking data. This will allow us to predict when waterfowl will be where, in response to shortand long-term global environmental change. 展开更多
关键词 Waterfowl migration · Environmentaldrivers · Phenology · Stopover ·Remote sensing ·Bird tracking
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The New Migration Movement, Citizenship and Institutional Change in the Global Age: A Political Understanding of Large-Scale Urban Migration of Rural Workers since the Reform in China
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作者 Yu Ke-ping 《Fudan Journal of the Humanities and Social Sciences》 2010年第2期1-25,共25页
Globalization accelerates the speed of migration in the world and challenges the traditional citizenship based on nation-state. Similarly, China has been undergoing a huge movement of domestic migration, more than 200... Globalization accelerates the speed of migration in the world and challenges the traditional citizenship based on nation-state. Similarly, China has been undergoing a huge movement of domestic migration, more than 200 million farmers moving into cities and towns from the countryside, under the impact of modernization and globalization; this creates a great challenge to its traditional citizenship. The paper includes five parts and will: 1 ) give an overview of the whole process of this huge migration since the Reform and Opening Up at the end of the 1970s ; 2 ) analyze the internal and international dynamics of migration and particularly its great challenges to citizens' civil rights, obhgation, and identity; 3 ) illustrate Chinese policies dealing with the new large migration; 4, ) assess the essential changes in citizenship from this migration; and 5 ) find its meaning and consequence in terms of political philosophy. 展开更多
关键词 rural worker citizen identity system change
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