检索结果-内蒙古大学图书馆

International Symposium on Telecommunications

作者： L. F. M. de Moraes P. D. Maciel Systems Engineering and Computer Science Program-COPPE/UFRJ High-Speed Networks Laboratory-RAVEL Rio de Janeiro Brazil

The Broadband Wireless Access (BWA) technology has been proposed to support different traffic classes with distinct quality of service (QoS) requirements in broadband metropolitan area networks. Therefore, as part of its specifications, such a system must properly address the combined requirements of wireless communications and multimedia applications. We propose in this paper an extension to the MAC protocol presented in [1, 2], by assigning variable priorities to the network stations sharing access to the communication channel. An analytical model to evaluate the performance of the proposed protocol is also developed and results obtained for the messages waiting times at different stations are presented. In addition, simulation data are used to compare the results obtained from the analytical model presented previously. It is concluded that the proposed variable priority MAC protocol is able to improve channel utilization and provide throughput and queueing delay fairness among the stations in the network.

关键词： Media Access Protocol Wireless application protocol Access protocols Analytical models Quality of service Telecommunication traffic Traffic control Metropolitan area networks Wireless communication Multimedia communication

来源：评论

学校读者我要写书评

暂无评论

Predicting Probability of Mortality in the Neonatal Intensive Care Unit

Predicting Probability of Mortality in the Neonatal Intensiv...

引用

Annual International Conference of the IEEE engineering in Medicine and Biology Society (EMBC)

作者： Dajie Zhou Monique Frize Program of Systems Science University of Ottawa Ottawa ONT Canada Department of Systems and Computer Engineering Carleton University and the School of Information Technology and Engineering University of Ottawa Ottawa ONT Canada

Artificial neural networks can be trained to predict outcomes in a neonatal intensive care unit (NICU). This paper expands on past research and shows that neural networks trained by the maximum likelihood estimation criterion will approximate the `a posteriori probability' of NICU mortality. A gradient ascent method for the weight update of three-layer feed-forward neural networks was derived. The neural networks were trained on NICU data and the results were evaluated by performance measurement techniques, such as the Receiver Operating Characteristic Curve and the Hosmer-Lemeshow test. The resulting models applied as mortality prognostic screening tools are presented

关键词： Pediatrics Neural networks Artificial neural networks Maximum likelihood estimation Measurement Testing Feedforward systems Feedforward neural networks Resource management Cities and towns

来源：评论

学校读者我要写书评

暂无评论

A neural model for sonar-based navigation in obstacle fields

A neural model for sonar-based navigation in obstacle fields

引用

IEEE International Symposium on Circuits and systems (ISCAS)

作者： T.K. Horiuchi Institute for Systems Research & The Neuroscience and Cognitive Science Program Electrical and Computer Engineering Department University of Maryland College Park MD USA

The rapid control of sonar-guided vehicles through obstacle fields has been a goal of robotics for decades. How sensory data is represented strongly affects how obstacles and goal information can be combined to select a direction of travel. While typical approaches combine attractive and repulsive effects to directly determine steering, we are investigating an algorithm that evaluates multiple directions simultaneously followed by a winner-take-all (WTA) function which then guides steering. In this paper we describe a neuromorphic VLSI implementation of this algorithm using the inherent echo delay to create a range-dependent gain in a 'race-to-first-spike' neural WTA circuit. The chip was fabricated in a commercially-available 0.5 mum CMOS process and in this paper we present preliminary test results

关键词： Sonar navigation Robot sensing systems Neurons Automotive engineering Neuroscience Cognitive science Educational institutions Control systems Vehicles Cognitive robotics

来源：评论

学校读者我要写书评

暂无评论

Predicting probability of mortality in the neonatal intensive care unit

Predicting probability of mortality in the neonatal intensiv...

引用

28th Annual International Conference of the IEEE engineering in Medicine and Biology Society, EMBS'06

作者： Dajie, Zhou Frize, Monique IEEE Program of Systems Science University of Ottawa 800 King Edward Ottawa Ont. K1N 6N5 Canada Department of Systems and Computer Engineering Carleton University University of Ottawa 1125 Colonel By Drive Ottawa Ont. K1S 5B5 Canada

ISBN: (纸本)1424400325

Artificial neural networks can be trained to predict outcomes in a neonatal intensive care unit (NICU). This paper expands on past research and shows that neural networks trained by the maximum likelihood estimation criterion will approximate the 'a posteriori probability' of NICU mortality. A gradient ascent method for the weight update of three-layer feed-forward neural networks was derived. The neural networks were trained on NICU data and the results were evaluated by performance measurement techniques, such as the Receiver Operating Characteristic Curve and the Hosmer-Lemeshow test The resulting models applied as mortality prognostic screening tools are presented. © 2006 IEEE.

关键词： Neonatal monitoring

来源：评论

学校读者我要写书评

暂无评论

Communications infrastructure generation for modular FPGA reconfiguration

Communications infrastructure generation for modular FPGA re...

引用

IEEE International Conference on Field-programmable Technology (FPT)

作者： Shannon Koh Oliver Diessel School of Computer Science and Engineering University of New South Wales Sydney Australia Embedded Real-Time and Operation Systems (ERTOS) Program NICTA Australia

Modules that are swapped dynamically at run-time on an FPGA have varying communication needs over time. In order to support this, we aim to generate a wiring infrastructure that caters for the dynamically-changing module interfaces. This, however, imposes a regular structure for laying out modules on a device, which may result in longer inter-module wiring paths as compared to traditional methods where the netlists are flattened. This paper studies placing modules within a structured layout to compare resulting circuit speeds with those obtained by traditional methods. Our results indicate that the difference in critical path delay is high at very low utilisation, but that the overhead is absorbed as the number of modules and interconnection density increases to realistic levels. The authors conclude that implementing such a wiring infrastructure has manageable overheads while having the added advantage of being amenable to dynamic reconfiguration

关键词： Field programmable gate arrays Wiring Australia Runtime Circuits Logic devices Reconfigurable logic computer science Real time systems Operating systems

来源：评论

学校读者我要写书评

暂无评论

COMMA: A Communications Methodology for Dynamic Module Reconfiguration in FPGAs

COMMA: A Communications Methodology for Dynamic Module Recon...

引用

Annual IEEE Symposium on Field-programmable Custom Computing Machines (FCCM)

作者： Shannon Koh Oliver Diessel School of Computer Science & Engineering University of New South Wales Sydney Australia Embedded Real Time and Operation Systems Program National ICT Australia NICTA Sydney Australia

On-going improvements in the scaling of FPGA device sizes and time-to-market pressures encourage the use of module-oriented design flows [3], while economic factors favour the reuse of smaller devices for high performance computational tasks. One of the core problems in proposing dynamic modular reconfiguration approaches is supporting the differing communications needs of the sequence of modules configured over time [2]. Proposals to date have not focussed on communications issues. Moreover, they have advocated the use of specific protocols [4], or they cannot be readily implemented [1], or they suffer from high overheads [5], or rely upon deprecated features such as tri-state lines [7]. In contrast, we propose a methodology for the rapid deployment of a communications infrastructure that provides the wires required by dynamic modules and allows users to implement the protocols they want. Our aim is to support new tiled dynamically reconfigurable architectures such as Virtex-4, as well as mature device families.

关键词： Field programmable gate arrays Pins Wiring Australia Protocols computer science Design engineering Real time systems Operating systems Time to market

来源：评论

学校读者我要写书评

暂无评论

ISHM implementation for Constellation systems

ISHM implementation for Constellation Systems

引用

AIAA/ASME/SAE/ASEE 42nd Joint Propulsion Conference

作者： Figueroa, Fernando Holland, Randy Schmalzel, John Duncavage, Dan Crocker, Alan Alena, Rick NASA Stennis Space Center Stennis Space Center MS 39529 Rowan University Dept. of Electrical and Computer Engineering Glassboro NJ 08028 NASA Johnson Space Center Houston TX 77058 NASA Ames Research Center Moffett Field CA 94035 Science and Technology Division EA41 Stennis Space Center MS 39529 AIAA Department of Electrical and Computer Engineering Rowan University Glassboro NJ 08028 International Space Station Program OD NASA Johnson Space Center Houston TX 77058 Systems Division Mission Operations Directorate DF NASA Johnson Space Center Houston TX 77058 Intelligent Systems Division MS 269-4 Moffett Field CA 94035

ISBN: (纸本)1563478188

This paper addresses methodic implementation of a credible ISHM capability for elements of Constellation systems. ISHM capability must be implemented by a combination of on-board and ground elements, each contributing to determining the health of systems in the most effective manner. Implementation of ISHM capability must evolve continuously to reach higher and higher levels of functional capability. The implication is that a sustainable approach must be defined in order to accomplish a believable capability. This paper describes the methodology, the elements, and the technology to implement ISHM capability throughout the life cycle of elements of Constellation systems, reaching beyond individual elements that might have a limited life while the constellation moves on.

关键词： Spacecraft propulsion

来源：评论

学校读者我要写书评

暂无评论

Real-time organ motion tracking and fast image registration system for MRI-guided surgery

引用

systems and computers in Japan 2006年第1期37卷 83-92页

作者： Tokuda, Junichi Hirano, Masaya Tsukamoto, Tetsuji Dohi, Takeyoshi Hata, Nobuhiko Graduate School of Information Science and Technology University of Tokyo Tokyo 113-8656 Japan GE Yokogawa Medical Systems Ltd. Hino 191-8503 Japan International Society for Computer-Aided Surgery Japan Society for Computer-Aided Surgery Japan Society for Magnetic Resonance in Medicine GE Yokogawa Medical Systems Ltd. Imaging Application Tech. Center MR Group R and D Laboratory Technology Center GE Yokogawa Medical Systems Ltd. Society for Magnetic Resonance in Medicine Graduate School of Information Science and Technology Society for Life Support Technology Japan Society for Organ Preservation Biology and Medicine Society for Precision Engineering Society for Medical Image Computing and Computer Assisted Intervention International Union for Physics and Engineering Sciences in Medicine JSMEBE Japan Society for Life Assistance Technology Brigham and Women's Hospital Harvard Medical School MR Therapy Program

The advantage of magnetic resonance imaging (MRI)-guided surgery, in which MR images taken during surgery are used to guide the surgery, has been recognized recently. However, there is a problem, due to long imaging time of MRI, that it is difficult to capture the respiratory organ motion. It is often a constraint that the patient must hold his or her breath, especially in the treatment of the abdominal region. Consequently, this paper proposes a method of eliminating this constraint in MRI-guided surgery by real-time monitoring of the movement of the organ involved in the surgery by means of the signal derived from MRI. Specifically, the navigator echo is extracted in imaging during surgery. The movement of the organ involved in surgery is detected on the basis of the change in the calculated projection profile, and the results are presented to the surgeon. In this study, the procedure is built into a 1.5-T clinical MRI system. The feasibility of the proposed system was examined under clinical conditions by evaluating its accuracy and delay in a phantom experiment, and also in an in vivo experiment on the liver of a volunteer. The results are reported in this paper. © 2005 Wiley Periodicals, Inc.

关键词： Motion estimation

来源：评论

学校读者我要写书评

暂无评论

Chitosan for Biofunctionalization of Microsystems

Chitosan for Biofunctionalization of Microsystems

引用

IEEE/NLM Life science systems and Applications Workshop

作者： Stephan T. Koev Michael A. Powers Vlad Badilita Hyunmin Yi William E. Bentley Gregory F. Payne Gary W. Rubloff Reza Ghodssi Institute for Systems Research ISR University of Maryland College Park MD USA University System of Maryland Adelphi MD US Department of Materials Science and Engineering University of Maryland College Park MD USA Department of Chemical Engineering University of Maryland College Park MD 20742 University of Maryland Biotechnology Institute (UMBI) University of Maryland College Park MD 20742 Bioengineering Graduate Program University of Maryland College Park MD 20742 University of Maryland College Park MD USA University of Maryland Biotechnology Institute College Park MD USA Institute for Systems Research (ISR) University of Maryland College Park MD 20742 Department of Materials Science and Engineering University of Maryland College Park MD 20742 Department of Electrical and Computer Engineering University of Maryland College Park MD 20742 Institute for Systems Research (ISR) University of Maryland College Park MD 20742

ISBN: (纸本)1424402778

We present the use of the polysaccharide chitosan for immobilizing biomolecules on microfabricated device surfaces. The main advantages of chitosan are its abundance of primary amine groups and its ability to be electrodeposited. Biomolecules are easily attached to chitosan 's amines by standard glutaraldehyde chemistry. The electrodeposition of chitosan allows accurate spatial and temporal control of biomolecule placement. We have demonstrated this biofunctionalization method for two different bioMEMS devices: a biophotonic sensor and a micromechanical biosensor. We have successfully assembled probe DNA on each of them and detected hybridization with target DNA as a demonstration of sensor operation. Here, we briefly present the fabrication procedure and testing results for both of these bioMEMS sensing devices

关键词： DNA Biosensors Molecular biophysics Probes Micromechanical devices Optical sensors Optical surface waves Optical interferometry Assembly Biomedical optical imaging

来源：评论

学校读者我要写书评

暂无评论

Data Storage Media Sanitization Procedures at the U.S. Agency For International Development (USAID)

引用

EDPACS 2006年第8期29卷 11-19页

作者： James Craft William Cleveland The Information Systems Security Officer at the United States Agency for International Development (USAID) Bureau for Management Information Resources Management (M/IRM) Information Systems Security Team. He has a BS in business management from George Mason University and has 22 years of experience focusing primarily on systems engineering cybersecurity and enterprise operations. He has played a major role in the implementation of the U.S. Government's Model Information Security Policy. The USAID PRIME Security Program Manager Computer Sciences Corporation in Arlington Virginia. He has MS degrees in information and telecommunications systems management and in military science. Cleveland has over 20 years of experience in the planning and management of a wide variety of functions including business process reengineering and IT security.

This article is derived from a Best Security Practice (BSP) developed by the U.S. Agency for International Development (USAID), Bureau for Management, Information Resources Management (M/IRM), Information systems Security Team. The USAID is an independent agency that provides economic, development, and humanitarian assistance around the world in support of the foreign policy goals of the United States. It is located in the Ronald Reagan Building in Washington, D.C.

关键词：

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：