检索结果-内蒙古大学图书馆

IEEE International Symposium on Intelligent Control (ISIC)

作者： S. van der Zwaan J.A.A. Moreira P.U. Lima Inst. de Sistema e Robotica Inst. Superior Tecnico Lisbon Portugal IInstituto de Sistemas e Robótica Instituto Superior Técnico Lisboa Portugal Instituto de Sistemas e Robótica Instituto Superior Técnico Lisboa Portugal

The paper deals with the the subject of learning and planning for real mobile robots, using Sutton's (1991) Dyna algorithm. The Dyna algorithm integrates reinforcement learning, planning and reactive execution. We present an extension of the Dyna algorithm which includes symmetric and cooperative learning with multiple robots. We applied the extended version of the algorithm to a population of two real robots. Practical problems associated with the implementation of the algorithm on a real setup are solved. Results obtained from simulations and real experiments are presented and discussed.

关键词： Learning Mobile robots Orbital robotics State-space methods density estimation robust algorithm Robot control Control systems Dynamic programming Costs Navigation

来源：评论

学校读者我要写书评

暂无评论

Penning collisions in a cold gas of trapped metastable helium atoms

Penning collisions in a cold gas of trapped metastable heliu...

引用

International Conference on Quantum Electronics (IQEC)

作者： J. Leonard F. Perales F.P. Dos Santos A. Sinatra Junmin Wang M. Leduc C. Cohen-Tannoudji Ecole Normale Superieure Paris ÃŽle-de-France FR Lab. Kastler Brossel Ecole Normale Superieure Paris France

ISBN: (纸本)0780363183

Summary form only given. We report progress on an experiment on trapped metastable /sup 4/He(2/sup 3/S/sub 1/) atoms which aims at producing a dense gas of ultra cold atoms, with the goal of reaching Bose-Einstein condensation. We have built a magneto-optical trap (MOT) in which we study the cold collisions, which are the main loss cause limiting the obtainable density.

关键词： Metastasis Helium Atomic measurements Atomic beams Fluorescence Nitrogen Optical collimators Ytterbium Doped fiber amplifiers density estimation robust algorithm

来源：评论

学校读者我要写书评

暂无评论

1.55 /spl mu/m, double-intracavity contacted, InP-lattice-matched VCSELs

1.55 /spl mu/m, double-intracavity contacted, InP-lattice-ma...

引用

IEEE Photonics Conference (IPC)

作者： S. Nakagawa E. Hall G. Almuneau J.K. Kim D.A. Buell H. Kroemer L.A. Coldren Department of Electrical and Computer Engineering and Materials University of California Santa Barbara CA USA University of California Santa Barbara Santa Barbara CA US

We demonstrate a 1.55 /spl mu/m, double-intracavity contacted VCSEL operating at room temperature under CW. The whole structure is completely lattice-matched to InP and grown at single step. A VCSEL with a 14 /spl mu/m diameter current aperture shows the threshold current of 2.0 mA and the maximum output power of 480 /spl mu/W at 25/spl deg/C, and it operates up to 60/spl deg/C. The threshold voltage and differential resistance are 1.3 V and 40 /spl Omega/, respectively, for a 10 /spl mu/m aperture VCSEL.

关键词： Vertical cavity surface emitting lasers Apertures Indium phosphide Superlattices Helium Kilns Electrons Gold density estimation robust algorithm Indium gallium arsenide

来源：评论

学校读者我要写书评

暂无评论

Energy storage and return in dynamic elastic response prosthetic feet

Energy storage and return in dynamic elastic response prosth...

引用

Pediatric Gait, A new Millennium in Clinical Care and Motion Analysis Technology

作者： M.D. Geil Georgia Institute of Technology Atlanta GA USA

Dynamic Elastic Response prosthetic feet are designed to store energy in midstance and return a portion of that energy to assist the amputee with push-off. While dozens of designs exist, the literature has not developed a consensus understanding of foot function. Several methods are explored to determine prosthesis energy storage and return, including joint translational power, segmental power, and prosthesis instrumentation.

关键词： Energy storage Prosthetics Foot density estimation robust algorithm Modems Springs Joints Instruments Electric shock Absorption

来源：评论

学校读者我要写书评

暂无评论

Data hiding in the bit stream domain for MPEG-2 coded video sequences exploiting space and frequency masking

Data hiding in the bit stream domain for MPEG-2 coded video ...

引用

International Conference on Acoustics, Speech, and Signal Processing (ICASSP)

作者： S. Arena M. Caramma R. Lancini CEFRIEL Milan Italy

In this paper a data hiding technique for MPEG-2 coded video sequences is presented. We have chosen to work in the bit stream domain in order to simplify the data embedding process in the case in which the original data are already in a compressed form. Thanks to the exploitation of an interleaved encoding technique and of some space and frequency masking considerations, we have been able to reduce the BER of the original algorithm. Some results underlining the improvements we have been able to obtain thanks to our technique are shown.

关键词： Data encapsulation Streaming media Video sequences Frequency Watermarking Video compression Decoding Encoding density estimation robust algorithm robustness

来源：评论

学校读者我要写书评

暂无评论

Cytokine receptor common β chain as a potential activator of cytokine withdrawal-induced apoptosis

引用

MOLECULAR AND CELLULAR BIOLOGY 1999年第11期19卷 7399-7409页

作者： Lee, SF Huang, HM Chao, JR Lin, S Yang-Yen, HF Yen, JJY Acad Sinica Inst Biomed Sci Taipei 11529 Taiwan Acad Sinica Inst Mol Biol Taipei 11529 Taiwan Natl Def Med Ctr Grad Inst Life Sci Taipei Taiwan Fu Jen Catholic Univ Grad Inst Biol Taipei Taiwan

Growth factors and cytokines play an important role in supporting cellular viability of various tissues during development due to their ability to suppress the default cell death program in each cell type. To date, neither the triggering molecule nor the transduction pathway of these default apoptosis programs is understood. In this study, we explored the possibility that cytokine receptors are involved in modulating cytokine withdrawal-induced apoptosis (CWIA) in hematopoietic cells. Expression of the exogenous cytokine receptor common beta chain (beta c), but not the alpha chains, accelerated CWIA in multiple cytokine-dependent cell lines. Reduction of the expression level of endogenous beta c by antisense transcripts resulted in prolonged survival during cytokine deprivation, suggesting a critical role of beta c in modulating CWIA. Fine mapping of the beta c subunit revealed that a membrane-proximal cytoplasmic sequence, designated the death enhancement region (DER), was critical to the death acceleration effect of beta c. Furthermore, DER accelerated cell death either as a chimeric membrane protein or as a cytosolic protein, suggesting that DER functions independently of the cytokine receptor and membrane anchorage. Cross-linking of the chimeric membrane-bound DER molecules by antibody or of the FK506-binding protein-DER fusion protein by a synthetic dimerizing agent, AP1510, did not abrogate the death acceleration effect. Transient transfection assays further indicated that DER promoted cell death in the absence of serum in the nonhematopoietic 293 cell line. In summary, our data suggest that beta c plays an important role in modulating CWIA via an anchorage-independent and aggregation-insensitive mechanism. These findings may facilitate further studies on the signaling pathways of CWIA.

关键词： Cytokine Receptors Cell Line Cell Death density estimation robust algorithm Cytokines cell type

来源：评论

学校读者我要写书评

暂无评论

Modeling of oxide-confined vertical cavity surface emitting lasers

Modeling of oxide-confined vertical cavity surface emitting ...

引用

International Conference on Transparent Optical Networks

作者： I.A. Sukhoivanov M.V. Samokhvalov Department of the Physical Foundation of Electronic Engineering Technical University of Radio Electronics Kharkov Ukraine

The given work is devoted to a problem of numerical simulation and analysis of the vertical cavity laser's parameters with the purpose of improving numerical simulation methods. The analysis of the VCSEL with the ... 详细信息

关键词： Vertical cavity surface emitting lasers Laser modes Surface emitting lasers Gallium arsenide density estimation robust algorithm Distributed Bragg reflectors Current density Refractive index Dielectric constant Equations

来源：评论

学校读者我要写书评

暂无评论

A pulp and paper simulator for operator training and process optimization

A pulp and paper simulator for operator training and process...

引用

European Control Conference (ECC)

作者： Carl-Fredrik Lindberg Erik Dahlquist Hakan Ekwall ABB Corporate Research Center Sweden Vasteras SE ABB Automation Systems 721 67 Västerås Sweden

A new dynamic simulator for pulp and paper applications has been developed. The simulator is useful for process optimization and operator training, especially when constructing a new paper machine, or rebuilding an existing one, or introducing new employees. The main advantage of the simulator is that the same control system (Distributed Control System source code) and the same displays in the Operator stations are used in the simulator as in the real plant. In this way process operators get very realistic training of various events. Optimization of an existing process line can be done by testing different ways of operation, and then selecting the best way of operation. A suitable rebuild of an existing mill could be found in a similar manner, i.e. by simulating different rebuild possibilities. A DCS functionality checkout can be done before startup of a real mill, since identical DCS code is used in the simulator as in the real mill.

关键词： Process control IP networks Graphical user interfaces density estimation robust algorithm

来源：评论

学校读者我要写书评

暂无评论

A thermal van der Pauw test structure

A thermal van der Pauw test structure

引用

IEEE International Conference on Microelectronic Test Structures

作者： O. Paul L. Plattner H. Baltes Institute for Microsystem Technology University of Freiburg Freiburg im Breisgau Germany Physical Electronics Laboratory ETH Hoenggerberg HPT Zurich Switzerland

A micromachined thermal van der Pauw test structure is reported. Similar in principle to the conventional electrical van der Pauw Greek cross test structures, it enables the in-plane thermal sheet conductivities of thin films to be determined. The analogy between the two-dimensional heat flow in thin film samples and the electrical current pattern in thin film conductors is exploited. A thermal sheet resistance of 1.87/spl times/10/sup 5/ K/W was extracted from the complete sandwich of dielectric layers of a commercial CMOS ASIC process. This is equivalent to an average in-plane thermal conductivity of the CMOS dielectric layer sandwich of /spl kappa/=1.44 Wm/sup -1/ K/sup -1/.

关键词： density estimation robust algorithm Testing Thermal conductivity Dielectric thin films Conducting materials Contacts Heating Resistors Current density Slabs

来源：评论

学校读者我要写书评

暂无评论

Micro-assembly planning with van der Waals force

Micro-assembly planning with van der Waals force

引用

IEEE International Symposium on Assembly and Manufacturing (ISAM)

作者： J.T. Feddema P. Xavier R. Brown Sandia National Laboratories Albuquerque NM USA Sandia National Laboratories Albuquerque NM US

Investigates a new aspect of fine motion planning for the micro-domain. As parts approach 1-10 /spl mu/m or less in outside dimensions, interactive forces such as van der Waals and electrostatic forces become major factors that greatly change the assembly sequence and path plans. It has been experimentally shown (Miyazaki and Sato, 1996, and Koyano and Sato, 1996) that assembly plans in the micro-domain are not reversible, motions required to pick up a part are not the reverse of motions required to release a part. The paper develops the mathematics required to determine the goal regions for pick up, holding, and release of a micro-sphere being handled by a rectangular tool.

关键词： density estimation robust algorithm Micromechanical devices Scanning electron microscopy Grippers Fixtures Laboratories Electrostatics Monolithic integrated circuits Robotic assembly Probes

来源：评论

学校读者我要写书评

暂无评论

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

请选择保存的检索档案：

请选择收藏分类：

通借通还

建议与咨询 留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

请选择保存的检索档案： 新增检索档案 确定 取消

请选择收藏分类： 新增自定义分类 确定 取消

通借通还

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

请选择保存的检索档案：

请选择收藏分类：