检索结果-南通市图书馆

Ceremonial Costumes of Qing-Dynasty Emperors

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

China & The World Cultural Exchange 2010年第6期76卷 20-23页

作者： chen weiguo

The Qing Dynasty, the last feudal dynasty in China, is known for its most sophisticated system for imperial costumes. Emperor

关键词：世界博览会礼仪服装穿着服饰茶叶曲江信息艺术

The Art of Tangka Painting

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

China & The World Cultural Exchange 2009年第10期75卷 30-33页

作者： chen weiguo

Apiece of Tangka painting is usually created with ten procedures, including cloth grinding, point positioning, outlining the contour with char pen, rough line drawing, color application, line drawing with fine brushwo... 详细信息

关键词：油画艺术品画家绘画技法

Temperature-Dependent Tearing Behavior of Rubber Materials:Characterization and Modeling

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Acta Mechanica Solida Sinica 2024年第2期37卷 316-326页

作者： Qinyuan Yao Feilong Zhang Pan Dong Ziyuan Zhao Yi He weiguo Li Liming chen State Key Laboratory of Coal Mine Disaster Dynamics and Control Chongqing UniversityChongqing400044China College of Aerospace Engineering Chongqing UniversityChongqing400044China

With the increasingly widespread application of rubber in many fields,there is a growing demand for quantitative characterization of temperature-dependent mechanical properties in high-temperature service *** critical tearing energy is an important criterion for determining whether rubber materials will experience tearing instability,while tear strength is a key parameter for rubber materials to resist *** is necessary to quantitatively characterize their evolution with *** theoretical research mainly relies on fitting a large amount of experimental data,which is not convenient for engineering ***,in this work,a temperature-dependent critical tearing energy model is firstly developed based on the force-heat equivalence energy density *** model considers the equivalent relationship between the critical tearing energy required for crack instability propagation and the thermal energy stored in the rubber *** is demonstrated that our model has higher prediction accuracy when compared to other ***,combining with the Griffith fracture theory,temperature-dependent tear strength models applicable to three different crack modes are separately *** models are validated using experimental data for Mode I opening cracks and ModeⅢtearing cracks,and good consistency is ***,a quantitative analysis of the influence of elastic modulus on tear strength at different temperatures is *** work provides a reliable way for predicting temperature-dependent tearing instability behavior and offers beneficial suggestions for improving the tear strength of rubber materials at different temperatures.

关键词： Temperature-dependent Critical tearing energy Tear strength Rubber Theoretical model

Energy dissipation mechanism and ballistic characteristic optimization in foam sandwich panels against spherical projectile impact

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Defence Technology（防务技术） 2024年第5期35卷 108-122页

作者： Jianqiang Deng Tao Liu Liming chen Xin Pan Jingzhe Wang Shaowei Zhu weiguo Li College of Aerospace Engineering Chongqing UniversityChongqing 400030China State Key Laboratory of Coal Mine Disaster Dynamics and Control Chongqing UniversityChongqing 400030China Chongqing Key Laboratory of Heterogeneous Material Mechanics Chongqing UniversityChongqing 400030China State Key Laboratory of Explosion Science and Technology Beijing Institute of TechnologyBeijing 100081China

This study systematically examines the energy dissipation mechanisms and ballistic characteristics of foam sandwich panels(FSP)under high-velocity impact using the explicit non-linear finite element *** on the geometric topology of the FSP system,three FSP configurations with the same areal density are derived,namely multi-layer,gradient core and asymmetric face sheet,and three key structural parameters are identified:core thickness(t_(c)),face sheet thickness(t_(f))and overlap face/core number(n_(o)).The ballistic performance of the FSP system is comprehensively evaluated in terms of the ballistic limit velocity(BLV),deformation modes,energy dissipation mechanism,and specific penetration energy(SPE).The results show that the FSP system exhibits a significant configuration dependence,whose ballistic performance ranking is:asymmetric face sheet>gradient core>*** mass distribution of the top and bottom face sheets plays a critical role in the ballistic resistance of the FSP *** BLV and SPE increase with tf,while the raising tcor noleads to an increase in BLV but a decrease in ***,a face-core synchronous enhancement mechanism is discovered by the energy dissipation analysis,based on which the ballistic optimization procedure is also conducted and a design chart is *** study shed light on the anti-penetration mechanism of the FSP system and might provide a theoretical basis for its engineering application.

关键词： Sandwich panel Numerical simulation Ballistic resistance Specific penetration energy Energy analysis

维普期刊数据库

Improving MapReduce Performance by Balancing Skewed Loads

在线全文

学校读者我要写书评

暂无评论

China Communications 2014年第8期11卷 85-108页

作者： FAN Yuanquan WU weiguo XU Yunlong chen Heng Department of Computer Science and Technology Xi'an Jiaotong University Xi'an 710049 Shaanxi Province P. R. China

MapReduce has emerged as a popular computing model used in datacenters to process large amount of *** the map phase,hash partitioning is employed to distribute data that sharing the same key across data center-scale cluster ***,we observe that this approach can lead to uneven data distribution,which can result in skewed loads among reduce tasks,thus hamper performance of MapReduce ***,worker nodes in MapReduce systems may differ in computing capability due to(1) multiple generations of hardware in non-virtualized data centers,or(2) co-location of virtual machines in virtualized data *** heterogeneity among cluster nodes exacerbates the negative effects of uneven data *** improve MapReduce performance in heterogeneous clusters,we propose a novel load balancing approach in the reduce *** approach consists of two components:(1) performance prediction for reducers that run on heterogeneous nodes based on support vector machines models,and(2) heterogeneity-aware partitioning(HAP),which balances skewed data for reduce *** implement this approach as a plug-in in current MapReduce *** results demonstrate that our proposed approach distributes work evenly among reduce tasks,and improves MapReduce performance with little overhead.

关键词： MapReduce cloud computing skewed loads performance prediction supportvector machines

维普期刊数据库

A LETTER OF GRATITUDE

在线全文

学校读者我要写书评

暂无评论

China's Tibet 2018年第4期29卷 9-12页

作者： chen weiguo Kong Xia

Tsewang Drolma once suffered from congenital heart disease,but she found recovery through the One Heart to Keep the Chinese Heart Beating public welfare *** express her heartfelt appreciation toward those people who remained committed to helping her,the following is her own personal letter."My name is Tsewang Drolma,and I have suffered from congenital heart disease since the time I was a little ***,though,I can live a healthy and happy life。

关键词： A LETTER GRATITUDE

Photonic crystal fiber with novel dispersion properties

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Frontiers of Optoelectronics 2009年第2期2卷 170-177页

作者： Shuqin LOU Shujie LOU Tieying GUO Liwen WANG weiguo chen Honglei LI Shuisheng JIAN Key Lab of All Optical Network and Advanced Telecommunication Network of EMC Beijing Jiaotong University Shandong Weifang Huaguang Precision Machinery Co.

Our recent research on designing microstructured fiber with novel dispersion properties is reported in this paper. Two kinds of photonic crystal fibers（PCFs） are introduced first. One is the highly nonlinear PCF with broadband nearly zero flatten dispersion. With introducing the germanium-doped（Ge-doped） core into highly nonlinear PCF and optimizing the diameters of the first two inner rings of air holes, a new structure of highly nonlinear PCF was designed with the nonlinear coefficient up to 47 W–1·km–1at the wavelength 1.55 μm and nearly zero flattened dispersion of ±0.5 ps/（km·nm） in telecommunication window（1460–1625 nm）. Another is the highly negative PCF with a ring of fluorin-doped（Fdoped） rods to form its outer ring core while pure silica rods to form its inner core. The peak dispersion – 1064ps/（km·nm） in 8 nm full width at half maximum（FWHM）wavelength range and – 365 ps/（km·nm） in 20 nm（FWHM） wavelength range can be reached by adjusting the structure parameters. Then, our recent research on the fabrication of PCFs is reported. Effects of draw parameters such as drawing temperature, feed speed, and furnace temperature on the geometry of the final photonic crystal fiber are investigated.

关键词： photonic crystal fiber (PCF) nearly zero flatten dispersion high nonlinear high negative dispersion fabrication technique

Effects of Nogo-neutralizing antibody and neurotrophin-3 on axonal regeneration following spinal cord injury in rats

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

Neural Regeneration Research 2008年第12期3卷 1319-1323页

作者： Ruisen Zhan Shijie chen weiguo Wang Haibin Long Department of Orthopedics the Third Xiangya Hospital Central South University Changsha 410013 Hunan Province China

BACKGROUND： Recent studies have suggested that regeneration of the central nerve fiber following spinal cord injury occurs under specific conditions. OBJECTIVE： To study the effects of Nogo-neutralizing antibody （IN-1）, in combination with neurotrophin-3 （NT-3）, on axonal regeneration and motor function following spinal cord injury in the rat. DESIGN, TIME AND SETTING： A randomized, controlled, animal study combining immunohistochemistry was performed at the Laboratory of Neuroanatomy of Xiangya Medical College, and Central Laboratory of Xiangya the Third Hospital, Central South University from January 2006 to December 2007. MATERIALS： Eighteen healthy, Sprague Dawley rats were randomly divided into three groups, with six rats per group： control, IN-l, and IN-1/NT-3. Hemisectioned spinal cord injury models were established by cutting the posterior 2/3 of spinal cord, which is equivalent to the Ts level. METHODS： A polyethylene tubing was inserted through into subarachnoid cavity, equivalent to the superior margin at the T8 level. Saline, IN-1, and IN-1/NT-3 were respectively injected into control, IN-1, and IN-1/NT-3 groups, three times/day for seven consecutive days. MAIN OUTCOME MEASURES： At 2 weeks post-surgery, biotin dextran amine （10%） was injected into the right sensorimotor cortex area. At day 28 post-surgery, spinal cord tissue was prepared for frozen sections Positive astrocytic expression was observed with glial fibrillary acidic protein （GFAP） immunohistochemical staining whose proliferation level was represented by gray value, i.e. the higher the gray value was, the less the positive cells were, and growth of positive fibers was observed with a biotin dextran amine histological reaction. Motor function was measured according to BBB scores pre-operatively, as well as at days 1, 7, 14, 21, and 28 post-operatively. RESULTS： Three rats died during experimentation. By random supplement, a total of 18 rats were included. GFAP-positive astrocytes were observe

关键词： Nogo-neutralizing antibody neurotrophin-3 biotin dextran amine glial fibrillary acidic protein spinal cord

维普期刊数据库