检索结果-南通市图书馆

Topology-optimized thermal metamaterials traversing full-parameter anisotropic space

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

npj Computational Materials 2022年第1期8卷 1717-1726页

作者： Wei Sha Run Hu mi Xiao Sheng Chu Zhan Zhu Cheng-Wei Qiu Liang Gao state Key Laboratory of Digital Manufacturing Equipment and Technology Huazhong University of Science and TechnologyWuhan430074China state Key Laboratory of Coal Combustion School of Energy and Power EngineeringHuazhong University of Science and TechnologyWuhan430074China School of engineering Cardiff UniversityCardiffCF243AAUnited Kingdom department of electrical and computer engineering National University of SingaporeKent Ridge117583Republic of Singapore

It is widely adopted in thermal metamaterials that mixing different materials could conveniently result in effective thermal conductivities(ETCs)beyond naturally-occurring *** multiple materials are isotropically mixed,the ETC is a direct average governed by their filling fractions and given bulk *** could lead to an inhomogeneous and anisotropic value within the maximal and minimal thermal conductivities of constituent *** thermal metadevices rely on anisotropic thermal conductivity tensor,whose tensorial elements are frequently inter-dependent and confined within a limited parametric *** is thus nontrivial to establish a design recipe for advanced thermal metamaterials whose ETCs could cover full-parameter anisotropic *** demonstrate topological functional cells(TFCs)with copper and polydimethylsiloxane,and show that the anisotropic ETCs traverse their full-parameter *** robust scheme based on topology-optimized TFCs unlocks unexplored opportunities for functional thermal metadevices whose parameters may not be reached in previous mixing *** study also sheds light on the developments in emerging acoustic,mechanical and electromagnetic composite materials.

关键词： parameter mixing thermal

A prediction mechanism of file access popularity and optimal strategy of replicas deployment in cloud computing

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

High Technology Letters 2015年第1期21卷 63-70页

作者：王宁 Yang Yang Chen Yu mi Zhenqiang Meng Kun Ji Qing School of computer and Communication engineering University of Science and Technology Beijing department of Mechanical and electrical engineering Yantai Engineering & Technology College department of computer Science and Technology Tsinghua University

In cloud computing,the number of replicas and deployment strategy have extensive impacts on user's requirement and storage ***,in this paper,a new definition of file access popularity according to users' preferences,and its prediction algorithm are provided to predict file access trend with historical *** are sorted by priority depending on their popularity.A mathematical model between file access popularity and the number of replicas is built so that the reliability is increased *** importantly,we present an optimal strategy of dynamic replicas deployment based on the file access popularity strategy with the overall concern of nodes' performance and load *** this strategy,files with high priority will be deployed on nodes with better performance therefore higher quality of service is *** strategy is realized in the Hadoop *** is compared with that of default strategy in Hadoop and CDRM *** result shows that the proposed strategy can not only maintain the system load balance,but also supply better service performance,which is consistent with the theoretical analysis.

关键词： cloud computing Hadoop file access popularity load balance quality of service

Transplantation of mesenchymal stem cells from human umbilical cord versus human umbilical cord blood for peripheral nerve regeneration

在线全文

学校读者我要写书评

暂无评论

Neural Regeneration Research 2010年第11期5卷 838-845页

作者： Kang-mi Pang mi-Ae Sung Mohammad S.Alrashdan Sang Bae Yoo Samir Jabaiti Soung-min Kim Sung-June Kim Myung-Jin Kim Jeong Won Jahng Jong-Ho Lee department of Oral Maxillofacial Surgery Seoul National University Seoul 110-768 Korea department of Craniofacial Structure & Functional Biology Seoul National University Seoul 110-768 Korea Dental Research Institute School of Dentistry Seoul National University Seoul 110-768 Korea department of Plastic and Reconstructive Surgery Faculty of Medicine Jordan University Hospital Amman 11942 Jordan department of electrical engineering School of Electrical and Computer Science Seoul National University Seoul 110-768 Korea

BACKGROUND： Mesenchymal stem cells （MSCs） appear to be a good alternative to Schwann cells in the treatment of peripheral nerve injury. Fetal stem cells, like umbilical cord blood （UCB） and umbilical cord （UC） stem cells, have several advantages over adult stem cells. OBJECTIVE： To assess the effects of UC-derived MSCs （UCMSCs） and UCB-derived MSCs （UCBMSCs） in repair of sciatic nerve defects. DESIGN, TIME AND SETTING： A randomized controlled animal experiment was performed at the laboratory of department of Oral and Maxillofacial Surgery, Seoul National university Dental Hospital, from July to December 2009. MATERIALS： UCMSCs were provided by the Research Institute of Biotechnology, Dongguk university. UCBMSCs were provided by the Laboratory of Stem Cells and Tumor Biology, College of Veterinary Medicine, Seoul National university. Dulbecco＇s modified Eagle＇s medium （DMEM） was purchased from Gibco-BRL, usa. METHODS： Seven-week-old Sprague-Dawley rats were randomly and evenly divided into three groups： DMEM, UCBMSCs, and UCMSCs. A 10-mm defect in the left sciatic nerve was constructed in all rats. DMEM （15 μL） containing 1×10^6 UCBMSCs or UCMSCs was injected into the gap between nerve stumps, with the surrounding epineurium as a natural conduit. For the DMEM group, simple DMEM was injected. MAIN OUTCOME MEASURES： At 7 weeks after sciatic nerve dissection, dorsal root ganglia neurons were labeled by fluorogold retrograde labeling. At 8 weeks, electrophysiology and histomorphometry were performed. At 2, 4, 6, and 8 weeks after surgery, sciatic nerve function was evaluated using gait analysis. RESULTS： The UCBMSCs group and the UCMSCs group exhibited similar sciatic nerve function and electrophysiological indices, which were better than the DMEM group, as measured by gait analysis （P 〈 0.05）. Fluorogold retrograde labeling of sciatic nerve revealed that the UCBMSCs group demonstrated a higher number of labeled neurons; however, the differences were not significant. His

关键词： peripheral nerve regeneration umbilical cord mesenchymal stem cell umbilical cord blood mesenchymal stem cell axotomy defect stem cells

大型电力系统在线暂态稳定计算中的加速距离同调识别法

在线全文

学校读者我要写书评

暂无评论

西安交通大学学报 1982年第5期 106-117页

作者：王世模沈赞埙李光琦西安交通大学电气工程系

本文提出一种新的加速距离同调识别法,这种方法据据线性化系统状态方程中决定各机组转子角加速度规律的有关物理量间的差别进行同调识别.理论论证和实例计算表明,这种方法与现有的几种同调识别法相比,具有物理概念清楚,计算简便迅速的特... 详细信息

本文提出一种新的加速距离同调识别法,这种方法据据线性化系统状态方程中决定各机组转子角加速度规律的有关物理量间的差别进行同调识别.理论论证和实例计算表明,这种方法与现有的几种同调识别法相比,具有物理概念清楚,计算简便迅速的特点.并且识别结果正确,简化效果显著,该方法与动态等效配合,应用于大型电力系统在线暂态稳定计算,占用内存减小,大为缩短计算时间。

关键词：同调识别加速距离大型电力系统运行方式暂态稳定计算大干扰稳定计算电力系统计算节点系统

Nonlinear Equations Solving with Intelligent Optimization Algorithms: A Survey

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

Complex System Modeling and Simulation 2021年第1期1卷 15-32页

作者： Wenyin Gong Zuowen Liao Xianyan mi Ling Wang Yuanyuan Guo School of computer Science China University of GeosciencesWuhan 430074China Development Research Center Beibu Gulf UniversityQinzhou 535000China College of Economics and Management Beibu Gulf UniversityQinzhou 535000China department of Automation Tsinghua UniversityBeijing 100084China Cvent Company FrederictonE3B 5H8Canada.

Nonlinear Equations(NEs),which may usually have multiple roots,are ubiquitous in diverse *** of the main purposes of solving NEs is to locate as many roots as possible simultaneously in a single run,however,it is a difficult and challenging task in numerical *** recent years,Intelligent Optimization Algorithms(IOAs)have shown to be particularly effective in solving *** paper provides a comprehensive survey on IOAs that have been exploited to locate multiple roots of *** paper first revisits the fundamental definition of NEs and reviews the most recent development of the transformation ***,solving NEs with IOAs is reviewed,followed by the benchmark functions and the performance comparison of several state-of-the-art ***,this paper points out the challenges and some possible open issues for solving NEs.

关键词： Nonlinear Equations(NEs) Intelligent Optimization Algorithms(IOA) multiple roots location transformation techniques diversity preservation

AgInS_(2)/ZnS quantum dots for noninvasive cervical cancer screening with intracellular pH sensing using fluorescence lifetime imaging microscopy

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Nano Research 2022年第6期15卷 5193-5204页

作者： Wenhua Su Dan Yang Yulan Wang Yawei Kong Wanlu Zhang Jing Wang Yiyan Fei Ruiqian Guo Jiong Ma Lan mi department of Optical Science and engineering Shanghai Engineering Research Center of Ultra-precision Optical ManufacturingKey Laboratory of Micro and Nano Photonic Structures(Ministry of Education)School of Information Science and TechnologyFudan UniversityShanghai 200433China Institute for Electric Light Sources School of Information Science and TechnologyFudan UniversityShanghai 200433China department of Gynecology and Obstetrics The Central Hospital of WuhanTongji Medical CollegeHuazhong University of Science and TechnologyWuhan 430014China Institute of Photonic Chips University of Shanghai for Science and TechnologyShanghai 200093China Centre for Artificial-Intelligence NanophotonicsSchool of Optical-Electrical and Computer EngineeringUniversity of Shanghai for Science and TechnologyShanghai 200093China Institute of Biomedical engineering and Technology Academy for Engineer and TechnologyFudan University220 Handan RoadShanghai 200433China Shanghai engineering Research Center of Industrial microorganisms the Multiscale Research Institute of Complex Systems(MRICS)School of Life SciencesFudan University220 Handan RoadShanghai 200433China

Intracellular pH plays a critical role in biological functions,and abnormal pH values are related to various ***,we report on an intracellular pH sensor AgInS_(2)(AIS)/ZnS quantum dots(QDs)that show long fluorescence lifetimes of hundreds of nanoseconds and low *** lifetime imaging microscopy(FLIM)combined with AIS/ZnS QDs is used for the imaging of live cells in different pH buffers and different cell *** FLIM images of AIS/ZnS QDs in live cells demonstrate different intracellular pH values in different regions,such as in lysosomes or *** method can also distinguish cancer cells from normal cells,and the fluorescence lifetime difference of the AIS/ZnS QDs between the two types of cells is 100±7 *** importantly,the exfoliated cervical cells from 20 patients are investigated using FLIM combined with AIS/ZnS *** lifetime difference value between the normal and cervical cancer(CC)groups is 115±9 ns,and the difference between the normal and the precancerous lesion group is 64±9 *** the first time,the noninvasive method has been used for cervical cancer screening,and it has shown great improvement in sensitivity compared with a clinical conventional cytology examination.

关键词： AIS/ZnS quantum dots fluorescence lifetime imaging microscopy intracellular pH sensing cervical cancer screening noninvasive

Spatio-Temporal Variability of Soil Salinity in Alluvial Plain of the Lower Reaches of the Yellow River——A Case Study

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Pedosphere 2011年第6期21卷 793-801页

作者： LI Kai-Li CHEN Jie TAN Man-Zhi ZHAO Bing-Zi mi Shu-Xiao SHI Xue-Zheng state Key Laboratory of Soil and Sustainable Agriculture Institute of Soil Science Chinese Academy of Sciences Nanjing 210008 （China） Graduate university of Chinese Academy of Sciences Beijing 100049 （China） department of Geography Jiangsu Institute of Education Nanjing 210013 （China） School of Water Conservation and Environment Zhengzhou University Zhengzhou 450000 （China）

Soil salinity and hydrologic datasets were assembled to analyze the spatio-temporal variability of salinization in Fengqiu County, Henan Province, China, in the alluvial plain of the lower reaches of the Yellow River. The saline soil and groundwater depth data of the county in 1981 were obtained to serve as a historical reference. electrical conductivity （EC） of 293 surface soil samples taken from 2 kin x 2 km grids in 2007 and 4{） soil profiles acquired in 2（108 was analyzed and used for comparative mapping. Ordinary kriging was applied to predict EC at unobserved locations to derive the horizontal and vertical distribution patterns and variation of soil salinity. Groundwater table data from 22 observation wells in 2008 were collected and used as input for regression kriging to predict the maximum groundwater depth of the county in 2008. Changes in the groundwater level of Fengqiu County in 27 years from 1981 to 2008 was calculated. Two quantitative criteria, the mean error or bias （ME） and the mean squared error （MSE）, were computed to assess the estimation accuracy of the kriging predictions. The results demonstrated that the soil salinity in the upper soil layers decreased dramatically and the taxonomically defined saline soils were present only in a few micro-landscapes after 27 years. Presently, the soils with relatively elevated salt content were mainly distributed in depressions along the Yellow River bed. The reduction in surface soil salinity corresponded to the locations with deepened maximum groundwater depth. It could be concluded that groundwater table recession allowed water to move deeper into the soil profile, transporting salts with it, and thus played an important role in reducing soil salinity in this region. Accumulation of salts in the soil profiles at various depths below the surface indicated that secondary soil salinization would occur when the groundwater was not controlled at a safe depth.

关键词： electrical conductivity groundwater table kriging salinization salt content

The 20-nm Skyrmion Generated at Room Temperature by Spin-Orbit Torques

在线全文

学校读者我要写书评

暂无评论

Chinese Physics Letters 2022年第1期39卷 40-45页

作者： Jiahao Liu Zidong Wang Teng Xu Hengan Zhou Le Zhao Soong-Guen Je mi-Young Im Liang Fang Wanjun Jiang state Key Laboratory of Low-Dimensional Quantum Physics and department of Physics Tsinghua UniversityBeijing 100084China Frontier Science Center for Quantum Information Tsinghua UniversityBeijing 100084China Institute for Quantum Information&state Key Laboratory of High Performance Computing College of ComputerNational University of Defense TechnologyChangsha 410073China Center for X-ray Optics Lawrence Berkeley National LaboratoryCyclotron RoadBerkeleyCA 94720USA department of Physics Chonnam National UniversityGwangju61186Republic of Korea

The discovery of magnetic skyrmions provides a promising pathway for developing functional spintronic memory and logic devices. Towards the future high-density memory application, nanoscale skyrmions with miniaturized diameters, ideally down to 20 nm are required. Using x-ray magnetic circular dichroism transmission microscopy,nanoscale skyrmions are observed in the [Pt/Co/Ir]15 multilayer at room temperature. In particular, small skyrmions with minimum diameters approaching 20 nm could be generated by the current-induced spin-orbit torques. Through implementing material specific parameters, the dynamic process of skyrmion generation is further investigated by performing micromagnetic simulations. According to the simulation results, we find that both the tube-like Neel-type skyrmions and the bobber-like Neel-type skyrmions can be electrically generated. In particular, the size of the bobber-like Neel-type skyrmions can be effectively reduced by the spin-orbit torques,which leads to the formation of 20 nm Neel-type skyrmions. Our findings could be important for understanding the formation dynamics of nanoscale Neel-type spin textures, skyrmions and bobber in particular, which could also be useful for promoting nanoscale skyrmionic memories and logic devices.

关键词： temperature diameters approaching

考虑暂态电压稳定的含高渗透率风光的电网动态无功规划方法

在线全文

学校读者我要写书评

暂无评论

电力自动化设备 2022年第8期42卷 79-88页

作者：徐艳春蒋伟俊汪平 mi Lu 三峡大学梯级水电站运行与控制湖北省重点实验室湖北宜昌443002 德克萨斯农工大学电气与计算机工程学院美国卡城77840

随着电网中风电、光伏渗透率的逐渐提高,电网暂态电压稳定问题愈加严重,提出一种考虑暂态电压稳定的含高渗透率风光的电网动态无功规划方法。构造基于电压二元表的区域暂态电压安全裕度指标和无功规划基准场景;基于所提指标给出动态无... 详细信息

随着电网中风电、光伏渗透率的逐渐提高,电网暂态电压稳定问题愈加严重,提出一种考虑暂态电压稳定的含高渗透率风光的电网动态无功规划方法。构造基于电压二元表的区域暂态电压安全裕度指标和无功规划基准场景;基于所提指标给出动态无功补偿装置的布点方法,建立差异化动态无功补偿优化模型,利用多目标灰狼优化算法求解配置容量,并采用改进的熵权逼近理想解距离法筛选出动态无功补偿装置的待配置方案;利用摄动法确定最终配置方案,确保所得规划方案适用于所有场景。改进的IEEE 39节点系统和实际电网的仿真结果验证了所提规划方法的普适性和合理性。

关键词：高渗透率风光暂态电压安全裕度指标基准场景差异化动态无功补偿改进的熵权TOPSIS法