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Low-magnitude whole body vibration with resistive exercise as a countermeasure against cardiovascular deconditioning after 60 days of head-down bed rest

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AMERICAN JOURNAL OF PHYSIOLOGY-REGULATORY INTEGRATIVE AND COMPARATIVE PHYSIOLOGY 2011年第6期301卷 R1748-R1754页

作者： Coupe, Mickael Yuan, Ming Demiot, Claire Bai, Yanqiang Q. Jiang, Shizhong Z. Li, Yongzhi Z. Arbeille, Philippe Gauquelin-Koch, Guillemette Levrard, Thibaud Custaud, Marc-Antoine Li, Yinghui H. Fac Med Angers UMR CNRS 6214 INSERM 771 Angers France China Astronaut Res & Training Ctr State Key Lab Space Med Fundamentals & Applicat Beijing Peoples R China Fac Pharm EA3842 Limoges France Ctr Hosp Univ Trousseau Tours France Ctr Natl Etud Spatiales Paris France Ctr Hosp Univ Angers Angers France

Coupe M, Yuan M, Demiot C, Bai YQ, Jiang SZ, Li YZ, Arbeille P, Gauquelin-Koch G, Levrard T, Custaud MA, Li YH. Low-magnitude whole body vibration with resistive exercise as a countermeasure against cardiovascular deconditioning after 60 days of head-down bed rest. Am J Physiol Regul Integr Comp Physiol 301: R1748-R1754, 2011. First published September 7, 2011;doi:10.1152/ajpregu.00234.2011.-Whole body vibration with resistive exercise is a promising countermeasure against some weightlessness-induced dysfunctions. Our objective was to study whether the combination of low-magnitude whole body vibration with a resistive exercise can prevent the cardiovascular deconditioning induced by a nonstrict 60-day head-down bed rest (Earth Star International Bed Rest Experiment Project). Fourteen healthy men participated in this study. We recorded electrocardiograms and blood pressure waves by means of a noninvasive beat-by-beat measurement system (Cardiospace, integrated by Centre National d'Etudes Spatiales and Astronaut Center of China) during an orthostatic test (20 min of 75-degree head-up tilt test) before and immediately after bed rest. We estimated heart rate, blood pressure, cardiac output, stroke volume, total peripheral resistance, baroreflex sensitivity, and heart rate variability. Low-magnitude whole body vibration with resistive exercise prevented an increase of the sympathetic index (reflecting the sympathovagal balance of cardiac autonomic control) and limited the decrease of the spontaneous baroreflex sensitivity induced by 60 days of head-down bed rest. However, this countermeasure had very little effect on cardiac hemodynamics and did not improve the orthostatic tolerance. This combined countermeasure did not efficiently prevent orthostatic intolerance but prevents changes in the autonomic nervous system associated with cardiovascular deconditioning. The underlying mechanisms remain hypothetical but might involve cutaneous and muscular mechanoreceptors.

关键词： autonomic nervous system cardiovascular deconditioning baroreflex hemodynamic head-up tilt test

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Near-Band-Edge Electroluminescence from Heavy-Metal-Free Colloidal Quantum Dots

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advanced MATERIALS 2011年第31期23卷 3553-+页

作者： Tan, Zhanao Zhang, Yu Xie, Chuang Su, Huaipeng Liu, Jie Zhang, Chunfeng Dellas, Nicholas Mohney, Suzanne E. Wang, Yongqiang Wang, Jingkang Xu, Jian Penn State Univ Dept Engn Sci & Mech University Pk PA 16802 USA N China Elect Power Univ Sch Renewable Energy New & Renewable Energy Beijing Key Lab Beijing 102206 Peoples R China Jilin Univ Coll Elect Sci & Engn State Key Lab Integrated Optoelect Changchun 130012 Peoples R China Tianjin Univ Sch Chem Engn & Technol State Key Lab Chem Engn Tianjin 300072 Peoples R China Ocean NanoTech LLC Springdale AR 72764 USA Penn State Univ Dept Mat Sci & Engn University Pk PA 16802 USA Penn State Univ Mat Res Inst University Pk PA 16802 USA Shanghai Univ Sci & Technol Shanghai 200093 Peoples R China

The first observation of near-band-edge electroluminescent emission from the colloidal quantum dots (QDs) consisting of CuInS2-ZnS alloyed (ZCIS) cores and ZnSe/ZnS double shells is reported. Bright and organic-free electroluminescence (EL) emission peaked at red (lambda = 623 nm), yellow (lambda = 594 nm), and green (lambda = 560 nm) wavelengths is observed from the heavy-metal-free QD light-emitting diodes (QD-LEDs). The onset voltages, luminance output uniformity, and efficiencies of the heavy-metal-free QD-LEDs are characterized.

关键词： electroluminescence quantum dots light‐emitting diodes

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Effects of slip condition on MHD stagnation-point flow over a power-law stretching sheet

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Applied Mathematics and Mechanics(English Edition) 2010年第4期31卷 439-448页

作者：朱婧郑连存张志刚 Department of Mathematics arid Mechanics University of Science and Technology Beijing

The steady two-dimensional magnetohydrodynamic stagnation flow towards a nonlinear stretching surface is studied. The no-slip condition on the solid boundary is replaced with a partial slip condition. A scaling group transformation is used to get the invariants. Using the invariants, a third-order ordinary differential equation corresponding to the momentum is obtained. An analytical solution is obtained in a series form using a homotopy analysis method. Reliability and efficiency of series solutions are shown by the good agreement with numerical results presented in the literature. The effects of the slip parameter, the magnetic field parameter, the velocity ratio parameter, the suction velocity parameter, and the power law exponent on the flow are investigated. The results show that the velocity and shear stress profiles are greatly influenced by these parameters.

关键词： boundary layer slip flow stagnation point scaling group transformation homotopy analysis method

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Bulk ZnO: Current status, challenges, and prospects

Bulk ZnO: Current status, challenges, and prospects

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作者： Avrutin, Vitaliy Cantwell, Gene Zhang, Jizhi Song, J.J. Silversmith, Donald J. Morkoç, Hadis Department of Electrical and Computer Engineering Virginia Commonwealth University Richmond VA 23284 United States ZN Technologies Inc. Brea CA 92821-2918 United States University of California at San Diego La Jolla CA 92093 United States Air Force Office of Scientific Research Arlington VA 22203 United States

Rediscovered in the last decade, zinc oxide (ZnO) shows a great potential for many optoelectronics and to some extent microelectronics applications. However, a clear majority of effort expended in this fast developing field has been limited to heteroepitaxial structures grown on foreign substrates with lattice-parameter and thermal-expansion mismatch with ZnO which is detrimental. Recognizing the importance, the effort has shifted to include developing technologies capable of producing freestanding ZnO wafers in large-scale for ZnO based device applications, which is the subject matter of this manuscript. Three competing approacheshydrothermal method, melt growth (modifications of the well known Bridgman technique), and seeded vapor transport growthhave now reached or are approaching commercial viability. In this article, we discuss the progress, outstanding problems, and prospects of these growth methods employed for commercial manufacturing of ZnO wafers. © 2010 IEEE.

关键词： Single crystals

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Multicast grooming algorithm in waveband switching optical networks

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Journal of Lightwave technology 2010年第19期28卷 2856-2864页

作者： Guo, Lei Wang, Xingwei Cao, Jiannong Hou, Weigang Pang, Lan College of Information Science and Engineering Northeastern University Shenyang 110819 China Department of Computing Hong Kong Polytechnic University Hong Kong Hong Kong State Key Laboratory of Advanced Optical Communication Systems and Networks Peking University Beijing 100871 China

In optical Wavelength-Division-Multiplexing (WDM) networks, multicast becomes more and more popular to provide high-speed communication between one point and multiple points. At the same time, the ports of Optical Cross-Connect (OXC) are greatly enhanced with the increasing number of wavelengths in fibers, and then the waveband switching technique is proposed to save the ports and reduce the cost of OXC. However, current waveband grooming algorithms are all limited in unicast. To achieve the multicast communication and meanwhile save the ports of OXC, we need to solve the multicast grooming, routing and wavelength/waveband assignment problem which is the HP-hard. In this paper, we propose a heuristic algorithm named Integrated Multicast Waveband Grooming (IMWG) based on Multicast Layered Auxiliary Graph (MLAG) that includes a Virtual Topology Layer (VTL) and multiple Waveband-Plane Layers (WPLs) to support the single-hop, multi-hop and hybrid multicast waveband grooming. For each demand, IMWG first computes a single-hop or multi-hop grooming waveband-tree on VTL. If the grooming waveband-tree cannot be found on VTL, IMWG computes a new waveband-tree on WPL. If the new waveband-tree cannot be found on WPL, IMWG computes a hybrid grooming waveband-tree on MLAG. Simulation results show that, compared with other algorithms, IMWG is able to obtain better performances. © 2010 IEEE.

关键词： Multicasting

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The Research of Tile Declustering in High-performance Heterogeneous Disk Systems

The Research of Tile Declustering in High-performance Hetero...

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2010 International Conference on Intelligent Computing and Integrated Systems

作者： Haifang Zhou School of Computer Science National University of Defence technology Changsha,410073 P.R China Guangjun Dong key laboratory of Land Resources Evaluation and Monitoring of Southwest(Sichuan Normal University) Information engineering University Shanghai Institute of Technical Physics Chengdou,Zhengzhou,Shanghai,China Ping Ren key laboratory of Land Resources Evaluation and Monitoring of Southwest(Sichuan Normal University) Chengdou,China Xue-qing Deng Institute of Surveying and Mapping Information engineering University Zhengzhou P.R China

The necessity of applying data declustering in Terrain Server System is discussed and two-dimensional declustering for tile-matrix of terrain data is *** studying the questions of data allocation and tile declustering in heterogeneous disk systems,a same-rate virtual disk dividing method and a vir-tual disk sorting method are *** method transform the heterogene-ous disk systems to same-rate virtual disk systems in order to ensure current data declustering method available for heterogeneous disk ***-tal results of response time and rate show that this method can manage massive terrain data and provide high data streams.

关键词： component Tile Declustering,terrain data

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Mechanical Properties Prediction of the Mechanical Clinching Joints Based on Genetic Algorithm and BP Neural Network

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Chinese Journal of Mechanical engineering 2009年第1期22卷 36-41页

作者： LONG Jiangqi LAN Fengchong CHEN Jiqing YU Ping School of Mechanical ＆ Automotive Engineering South China University of Technology Guangzhou 510641 China

For optimal design of mechanical clinching steel-aluminum joints, the back propagation （BP） neural network is used to research the mapping relationship between joining technique parameters including sheet thickness, sheet hardness, joint bottom diameter etc., and mechanical properties of shearing and peeling in order to investigate joining technology between various material plates in the steel-aluminum hybrid structure car body. Genetic algorithm （GA） is adopted to optimize the back-propagation neural network connection weights. The training and validating samples are made by the BTM Tog-L-Loc system with different technologic parameters. The training samples＇ parameters and the corresponding joints＇ mechanical properties are supplied to the artificial neural network （ANN） for training. The validating samples＇ experimental data is used for checking up the prediction outputs. The calculation results show that GA can improve the model＇s prediction precision and generalization ability of BP neural network. The comparative analysis between the experimental data and the prediction outputs shows that ANN prediction models after training can effectively predict the mechanical properties of mechanical clinching joints and prove the feasibility and reliability of the intelligent neural networks system when used in the mechanical properties prediction of mechanical clinching joints. The prediction results can be used for a reference in the design of mechanical clinching steel-aluminum joints.

关键词： genetic algorithm BP neural network mechanical clinching joint properties prediction

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Measurement scheduling for soil moisture sensing: From physical models to optimal control

Measurement scheduling for soil moisture sensing: From physi...

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作者： Shuman, David I. Nayyar, Ashutosh Mahajan, Aditya Goykhman, Yuriy Li, Ke Liu, Mingyan Teneketzis, Demosthenis Moghaddam, Mahta Entekhabi, Dara Institute of Electrical Engineering École Polytechnique Fédérale de Lausanne 1015 Lausanne Switzerland Electrical Engineering and Computer Science Department University of Michigan Ann Arbor MI 48109 United States Department of Electrical and Computer Engineering McGill University Montreal QC H3A 2T5 Canada State Key Laboratory of Precision Management Technology and Instruments Tsinghua University Beijing 100084 China Department of Civil and Environmental Engineering Massachusetts Institute of Technology Cambridge MA 02138 United States

In this paper, we consider the problem of monitoring soil moisture evolution using a wireless network of in situ sensors. Continuously sampling moisture levels with these sensors incurs high-maintenance and energy consumption costs, which are particularly undesirable for wireless networks. Our main hypothesis is that a sparser set of measurements can meet the monitoring objectives in an energy-efficient manner. The underlying idea is that we can trade off some inaccuracy in estimating soil moisture evolution for a significant reduction in energy consumption. We investigate how to dynamically schedule the sensor measurements so as to balance this tradeoff. Unlike many prior studies on sensor scheduling that make generic assumptions on the statistics of the observed phenomenon, we obtain statistics of soil moisture evolution from a physical model. We formulate the optimal measurement scheduling and estimation problem as a partially observable Markov decision problem (POMDP). We then utilize special features of the problem to approximate the POMDP by a computationally simpler finite-state Markov decision problem (MDP). The result is a scalable, implementable technology that we have tested and validated numerically and in the field. © 2010 IEEE.

关键词： Scheduling

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Exchange interaction in rapidly solidified nanocrystalline RE-(Fe/Co)-B hard magnetic alloys

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JOURNAL OF APPLIED PHYSICS 2009年第7期105卷

作者： Liu, Z. W. Zeng, D. C. Ramanujan, R. V. Zhong, X. C. Davies, H. A. S China Univ Technol Sch Mat Sci & Engn Guangzhou 510640 Guangdong Peoples R China Univ Sheffield Dept Mat Engn Sheffield S1 3JD S Yorkshire England Nanyang Technol Univ Sch Mat Sci & Engn Singapore 639798 Singapore

The exchange interactions for rapidly solidified (Nd/Pr)(Fe/Co)B hard magnetic alloys with remanence enhancement were studied by analyzing characteristic magnetic curves and Henkel plots. The exchange coupling can be improved by increasing soft phase content within hard matrix. With increasing temperature, the exchange interaction is enhanced due to the increased exchange length. An increased recoil susceptibility was found for the alloys with improved exchange coupling. Analysis of the microstructure parameters indicated that Co substituting Fe and introducing soft alpha-(Fe,Co) phase not only reduce the stray field effects but also enhance the exchange interaction. (C) 2009 American Institute of Physics. [DOI: 10.1063/1.3072717]

关键词： Nanocrystals

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Comparison and analysis of fusion algorithms of high resolution imagery

Comparison and analysis of fusion algorithms of high resolut...

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International Conference on Photoelectronic Detection and Imaging

作者： Dong Guangjun Huang Xiaobo Dai Chenguang Beijing Normal Univ State Key Lab Remote Sensing Sci Beijing 100101 Peoples R China Chinese Acad Sci Inst Remote Sensing Applicat Beijing 100101 Peoples R China Chinese Acad Sci Inst Remote Sensing Applicat State Key Lab Remote Sensing Sci Beijing 100101 Peoples R China Beijing Normal Univ Beijing 100101 Peoples R China Informat Engn Univ Inst Surveying & Mapping Zhengzhou 450052 Peoples R China

ISBN: (纸本)9780819467676

The fusion techniques have been developed quickly in recent years and become an important remote sensing research topic. This paper systematically discusses the technique used in pixel level image fusion including IHS transform, YIQ transform, HLS transform, HSV transform, PCA transform, HPF transform and wavelet transform image fusion method. Then a fusion experiment of IKONOS image is made to compares the different merging methods from spectral quality and the spatial quality in order to choose the suitable method for the high resolution image.

关键词： information fusion wavelet transform PCA transform BPF transform

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