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Wuhan University Journal of Natural Sciences 2007年第3期12卷 529-534页

作者： WANG qin JIANG Lin WEN Qibiao College of Light Industry and Food South China University of Technology Guangzhou 510640 Guangdong China College of Light Industry and Food Zhongkai University of Agriculture and Technology Guangzhou 510225 Guangdong China School of Pharmaceutical Sciences Sun Yat-sen University Guangzhou 510080 Guangdong China

The physical properties and chemical components of three oil samples extracted from Illicium verum Hook. f. by steam distillation （SD）, solvent extraction （SE） and supercritical fluid extraction （SFE） were compared with one another and analyzed by Gas Chromatography-Mass Spectrometry （GC-MS）. The quality parameters of star anise essential oil from SFE were close to that of those came from SD and SE. Although the extraction yield of star anise by SFE （9.2 %） was close to the value from SE （9.3%）, it was yet higher than that came from SD （8.2%）. For sensory evaluation, however, three oils were significantly different. The odor and taste of the products from SFE and SE were generally more natural and vivid than that came from distilled oil. The volatile compound revealed that significant differences of the composition existed in the distilled oil and the oleoresins prepared by SFE and SE.

关键词： Illicium verum Hook. f. steam distillation solvent extraction supercritical fluid extraction GC-MS

Multi-Dimensional Customer Data Analysis in Online Auctions

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Wuhan University Journal of Natural Sciences 2007年第5期12卷 793-798页

作者： LAO Guoling XIONG Kuan qin Zheng School of Information Management and Engineering Shanghai University of Finance and Economics Shanghai 200433 China

In this paper, we designed a customer-centered data warehouse system with five subjects： listing, bidding, transaction, accounts, and customer contact based on the business process of online auction companies. For each subject, we analyzed its fact indexes and dimensions. Then take transaction subject as example, analyzed the data warehouse model in detail, and got the multi-dimensional analysis structure of transaction subject. At last, using data mining to do customer segmentation, we divided customers into four types： impulse customer, prudent customer, potential customer, and ordinary customer. By the result of multi-dimensional customer data analysis, online auction companies can do more target marketing and increase customer loyalty.

关键词： online auction data warehouse online analytic process (OLAP) data mining E-commerce

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5G对中国碳排放峰值的影响研究

中国环境科学 2021年第3期41卷 1447-1454页

作者：谭萌彭艺马戎秦汉时湖北经济学院碳排放权交易湖北省协同创新中心湖北武汉430205 湖北经济学院低碳经济学院湖北武汉430205 复旦大学经济学院上海200433

基于目前5G技术的发展情况,利用holt指数平滑法和动态分析法预测了未来20年5G基站产生的直接碳排放量.根据预测模型,5G基站建设会在2038年左右达到饱和状态,数量约为1434万个.考虑到5G技术的发展推动其他产业发展可能导致的碳排放量变化... 详细信息

基于目前5G技术的发展情况,利用holt指数平滑法和动态分析法预测了未来20年5G基站产生的直接碳排放量.根据预测模型,5G基站建设会在2038年左右达到饱和状态,数量约为1434万个.考虑到5G技术的发展推动其他产业发展可能导致的碳排放量变化,利用投入产出法和灰度时间预测法等方法评估了5G技术引起的各行业间接碳排放量.结果显示,5G基站处于低负载(30%负载)情况下,能在2038年碳排放达峰时年产生142.61Mt的直接碳排放;而如果满负荷运行,则能在2038年碳排放达峰时产生196.26Mt的直接碳排放,基于中国两种不同碳排放达峰情景,综合分析了5G技术导致的直接和间接碳排放对中国碳排放达峰时间和碳排放峰值的影响,最后对预测结果进行了稳健性检验.研究发现,实际GDP情况情景下5G技术对于社会各行业的碳排放影响在2030年达到峰值,约为255.96Mt.并且,2030年前5G技术发展对社会总体碳排放增量以间接碳排放为主,2030年后对社会碳排放增量以直接碳排放为主;综合考虑下5G技术的发展会导致中国碳排放达峰时间推后至少2年,相应的碳排放峰值至少提高了383.96Mt.若中国政府要削减5G导致的额外碳排放,完成二氧化碳总量控制,需要降低基站能耗水平,控制基站数量,避免重复建设导致5G基站低负荷运行.

关键词： 5G技术碳排放峰值间接碳排放情景分析法

Insights into mercury in glacier snow and its incorporation into meltwater runoff based on observations in the southern Tibetan Plateau

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Journal of Environmental Sciences 2018年第6期30卷 130-142页

作者： Shiwei Sun Shichang Kang Junming Guo Qianggong Zhang Rukumesh Paudyal Xuejun Sun Dahe qin State Key Laboratory of Cryospheric Science Northwest Institute of Eco-Environment and Resources Chinese Academy of Sciences Lanzhou 730000 China Key Laboratory of Tibetan Environment Changes and Land Surface Processes Institute of Tibetan Plateau Research Chinese Academy of Sciences Beijing 100101 China CAS Center for Excellence in Tibetan Plateau Earth Sciences Beijing 100101 China University of Chinese Academy of Sciences Beijing 100049 China

The Tibetan Plateau（TP） is recognized as ＂Water Tower of Asia＂. Yet our understanding of mechanisms influencing incorporation of mercury（Hg） into freshwater in mountain glaciers on the TP remains quite limited. Extensive sampling of environmental matrices（e.g., snow/ice）were conducted on the East Rongbuk glacier on Mt. Everest and Zhadang glacier on *** for Hg speciation analysis. Speciated Hg behaved quite different during snowmelt： a preferential early release of DHg（dissolved Hg） was observed at the onset of snowmelt, whereas PHg（particulate-bound Hg） and THg（total Hg） become relatively enriched in snow and released later. Small fraction of Hg in snow was lost during a snowmelt day（18.9%–34.7%） with a large proportion（58.1%–87.3%） contributed by PHg decrease, indicating that the deposited Hg is most likely retained in glacier snow/ice. Furthermore, THg were positively correlated with PHg and crustal major ions（e.g., Ca2＋, Mg2＋） during snowmelt, indicating that Hg is mainly migrated with particulates. The main pathway of Hg loss during snowmelt was most probably associated with release of PHg with meltwater, which was greatly influenced by ablation intensity of snow/ice. This should be paid particular concern as Hg preserved in mountain glaciers will mostly enter aquatic ecosystem as climate warms, impacting on downstream ecosystems adversely. Obvious decrease of THg during the downstream transport from glacier was observed with a large proportion contributed by PHg decrease. The main removal mechanism of Hg was associated with sedimentation of PHg during the transport process.

关键词： Mercury speciation Snow/ice Migration Transport Mountain glacier Tibetan Plateau

A One Health strategy for emerging infectious diseases based on the COVID-19 outbreak

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Journal of Biosafety and Biosecurity 2022年第1期4卷 5-11页

作者： qin Wu Qianlin Li Jiahai Lu School of Public Health Sun Yat-sen UniversityGuangzhouChina Key Laboratory for Tropical Disease Control Sun Yat-sen UniversityMinistry of EducationGuangzhouChina One Health Center of Excellence for Research and Training GuangzhouChina State Key Laboratory for Surveillance and Evaluation of Vaccines and Biological Products GuangzhouChina

Coronavirus disease 2019(COVID-19)is as an emerging infectious disease(EID)that has caused the worst public health catastrophe of the 21st century thus *** terms of impact,the COVID-19 pandemic is second only to the Spanish Flu pandemic of 1918 in modern world *** of 7 September 2021,there have been 220 million confirmed cases of COVID-19 and more than 4.5 million *** pose serious public health and socio-economic risks,and 70%of EIDs originate from *** development of EIDs such as COVID-19 is a pressing ***,taking the COVID-19 pandemic as an example,we illustrate the disastrous effects of EIDs and assess their emergence and evolution from a One Health *** propose a One Health strategy,centered on‘moving the gates forward’,for EID prevention and control at the human-animal-environment *** strategy may be instructive and provide early warnings of EIDs in the future.

关键词： COVID-19 Emerging infectious diseases Zoonotic One Health Human-animal-environment interface Early warning

Research on virtual actor action editing and movement control

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Frontiers of Electrical and Electronic Engineering in China 2008年第1期3卷 49-54页

作者： Wenhu qin Yuhui WU Zhengxu ZHAO Department of Instrument Science and Engineering Southeast UniversityNanjing 210096China

To directly use a virtual surface model for action editing and movement control,a general method for creating virtual actor skeleton models and controlling movement is *** method includes judging borderlines of the block virtual surface model,calculating the joints,confirming the above block,and using the block hierarchical layout to create the skeleton ***,according to the virtual actor model and movement restriction,the study focuses on the generation of movement animation using the key frame technique and smoothing movement technique by automatically adding animation and adjusting the actor’s pose by different weights on movement ***,movement control of the actor in the virtual environment is implemented by real-time control and path point control,which achieve a good result.

关键词： virtual actor skeleton model move model move control

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面向时延优化的Overlay路由策略研究

计算机学报 2010年第1期33卷 36-44页

作者：叶枰李益忠夏勤东南大学计算机网络和信息集成教育部重点实验室南京210096 东南大学计算机科学与工程学院南京210096

路由扩展性是Overlay网络的研究热点,其中网络时延作为Overlay路由性能的一个关键指标已成为重点研究内容之一.文中对Overlay路由及其扩展性问题进行描述,并在此基础上进行数学建模和分析.针对时延优化目标,提出一种基于蚁群算法的单跳... 详细信息

路由扩展性是Overlay网络的研究热点,其中网络时延作为Overlay路由性能的一个关键指标已成为重点研究内容之一.文中对Overlay路由及其扩展性问题进行描述,并在此基础上进行数学建模和分析.针对时延优化目标,提出一种基于蚁群算法的单跳路由路径策略来处理邻居节点集合维护的问题:通过蚂蚁爬行的过程建立邻居节点集合,并根据设定的质量评估函数进行修剪来控制每个节点上维护的邻居节点集合大小.通过仿真实验对Overlay路由性能进行的分析,证实了Overlay路由在时延优化方面的可行性,同时实验结果表明了ACOHPR在对平均时延影响很小的情况下能够有效地降低每个节点的邻居节点集合大小.

关键词：时延优化单跳路径路由 Overlay路由蚁群算法邻居节点集合

微波消解-原子吸收光谱法测定不同产地淡竹叶中微量元素的含量

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光谱学与光谱分析 2010年第3期30卷 804-808页

作者：袁珂薛月芹桂仁意孙素琴殷明文浙江林学院天然药物研发中心浙江临安311300 清华大学化学系北京100084 郑州大学化学系河南郑州450052

利用微波消解技术处理样品,采用原子吸收光谱法测定了我国广东、湖北、湖南、重庆、广西、江苏、福建、浙江、安徽九个不同产区淡竹叶中Zn,Fe,Cu,Mn,K,Ca,Mg,Ni,Cd,Pb,Cr,Co,Al,Se,As 15种微量元素的含量。该方法的相对标准偏差（RSD）... 详细信息

利用微波消解技术处理样品,采用原子吸收光谱法测定了我国广东、湖北、湖南、重庆、广西、江苏、福建、浙江、安徽九个不同产区淡竹叶中Zn,Fe,Cu,Mn,K,Ca,Mg,Ni,Cd,Pb,Cr,Co,Al,Se,As 15种微量元素的含量。该方法的相对标准偏差（RSD）在1.23%~3.32%之间,平均回收率在95.8%~104.2%之间。研究表明,该方法简便、快速、灵敏,适合于淡竹叶中微量元素的测定。试验分析结果表明,不同产地淡竹叶中微量元素的含量呈现地域性差异。各地区的淡竹叶中对人体有益的元素K,Mg,Ca,Fe,Mn含量普遍较丰富对人体有害的重金属元素,除湖南产的淡竹叶中Pb的含量稍高,广东、安徽产的淡竹叶中Cu的含量偏高外,其他产区的淡竹叶中有害重金属元素Cd,Cu,Cr,Pb,As的含量均低于《中国药典》、《药用植物及其制剂进出口绿色行业标准》及《国家标准食品卫生标准》的限量标准。该测定结果为进一步探讨淡竹叶中微量元素的含量与其功效的相关性提供了科学依据。

关键词：微波消解原子吸收光谱法淡竹叶微量元素

无线传感器网络下线性支持向量机分布式协同训练方法研究

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电子与信息学报 2015年第3期37卷 708-714页

作者：及歆荣侯翠琴侯义斌北京工业大学嵌入式软件与系统研究所北京100124 河北工程大学信息与电气工程学院邯郸056038

针对无线传感器网络中分散在各节点上的训练数据传输到数据融合中心集中训练支持向量机(Support Vector Machine,SVM)时存在的高通信代价和高能量消耗问题,该文研究了仅依靠相邻节点间的相互协作,在网内分布式协同训练线性SVM的方法。首... 详细信息

针对无线传感器网络中分散在各节点上的训练数据传输到数据融合中心集中训练支持向量机(Support Vector Machine,SVM)时存在的高通信代价和高能量消耗问题,该文研究了仅依靠相邻节点间的相互协作,在网内分布式协同训练线性SVM的方法。首先,在各节点分类器决策变量与集中式分类器决策变量相一致的约束下,对集中式SVM训练问题进行等价分解,然后利用增广拉格朗日乘子法,对分解后的SVM问题进行求解和推导,进而提出基于全局平均一致性的线性SVM分布式训练算法(Average Consensus based Distributed Supported Vector Machine,AC-DSVM);为了降低AC-DSVM算法中全局平均一致性的通信开销,利用相邻节点间的局部平均一致性近似全局平均一致性,提出基于一次全局平均一致性的线性SVM分布式训练算法(Once Average Consensus based Distributed Supported Vector Machine,1-AC-DSVM)。仿真实验结果表明,与已有算法相比,AC-DSVM算法的迭代次数和数据传输量略高,但其能够完全收敛到集中式训练结果;1-AC-DSVM算法具有较好的收敛性,而且在收敛速度和数据传输量上也表现出显著优势。

关键词：无线传感器网络支持向量机分布式学习增广拉格朗日乘子法平均一致性