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91.
智能电源系统在信号领域中的应用 总被引:1,自引:0,他引:1
随着轨道交通的发展,信号设备要求具备智能化、模块化、自动化、网络化的智能电源系统。针对信号系统的发展对智能电源系统的要求,阐述了智能电源系统在智能化、模块化、自动化三方面的应用。介绍了目前智能电源系统所采用各种不同的技术方案,并论述了方案的优缺点,总结了目前存在的问题和发展方向。 相似文献
92.
Ian Flood 《Advanced Engineering Informatics》2008,22(1):4-14
The purpose of this paper is to stimulate interest within the civil engineering research community for developing the next generation of applied artificial neural networks. In particular, it identifies what the next generation of these devices needs to achieve, and provides direction in terms of how their development may proceed. An analysis of the current situation indicates that progress in the development of artificial neural network applications has largely stagnated. Suggestions are made for advancing the field to the next level of sophistication and application, using genetic algorithms and related techniques. It is shown that this approach will require the design of some very sophisticated genetic coding mechanisms in order to develop the required higher-order network structures, and will utilize development mechanisms observed in nature such as growth, self-organization, and multi-stage objective functions. The capabilities of such an approach and the way in which they can be achieved are explored with reference to the problems of: (a) determining truck attributes from the strain envelopes they induce in structural members when crossing a bridge, and; (b) developing a decision support system for dynamic control of industrialized manufacturing of houses. 相似文献
93.
Enver Sangineto Nicola Capuano Matteo Gaeta Alessandro Micarelli 《Universal Access in the Information Society》2008,7(1-2):1-23
This paper presents an approach to automatic course generation and student modeling. The method has been developed during
the European funded projects Diogene and Intraserv, focused on the construction of an adaptive e-learning platform. The aim
of the platform is the automatic generation and personalization of courses, taking into account pedagogical knowledge on the
didactic domain as well as statistic information on both the student’s knowledge degree and learning preferences. Pedagogical
information is described by means of an innovative methodology suitable for effective and efficient course generation and
personalization. Moreover, statistic information can be collected and exploited by the system in order to better describe
the student’s preferences and learning performances. Learning material is chosen by the system matching the student’s learning
preferences with the learning material type, following a pedagogical approach suggested by Felder and Silverman. The paper
discusses how automatic learning material personalization makes it possible to facilitate distance learning access to both
able-bodied and disabled people. Results from the Diogene and Intraserv evaluation are reported and discussed. 相似文献
94.
We present a novel mobile code management environment,currently under design and development. Our design employs anopen architecture, suitable for ``plug-and-play' with COTS andother groups' tools. While we have studied new algorithms, costand objective functions, and other fundamental issues, the maincontribution of this experimental research work is in the environmentitself. It should be noted that networked platforms, such asthe World Wide Web, are inherently not suitable for traditional,predictable real-time applications. Thus, real-time concernsnecessarily need to be blended with others concerns, and thetarget applications, making use of our environment, will toobe a blend of partially hard real-time and partially (or mostly)soft-real- time ones. The prototype environment will thereforesupport performance-based analysis and management focusing notonly on predictability but also on compilation, efficiency, safetyand other tradeoffs. We have selected the Java language and itsbytecode format as a representation for mobile code as well asa language for our implementation. 相似文献
95.
Recently, High Performance Computing (HPC) platforms have been employed to realize many computationally demanding applications
in signal and image processing. These applications require real-time performance constraints to be met. These constraints
include latency as well as throughput. In order to meet these performance requirements, efficient parallel algorithms are
needed. These algorithms must be engineered to exploit the computational characteristics of such applications.
In this paper we present a methodology for mapping a class of adaptive signal processing applications onto HPC platforms
such that the throughput performance is optimized. We first define a new task model using the salient computational characteristics
of a class of adaptive signal processing applications. Based on this task model, we propose a new execution model. In the
earlier linear pipelined execution model, the task mapping choices were restricted. The new model permits flexible task mapping
choices, leading to improved throughput performance compared with the previous model. Using the new model, a three-step task
mapping methodology is developed. It consists of (1) a data remapping step, (2) a coarse resource allocation step, and (3)
a fine performance tuning step. The methodology is demonstrated by designing parallel algorithms for modern radar and sonar
signal processing applications. These are implemented on IBM SP2 and Cray T3E, state-of-the-art HPC platforms, to show the
effectiveness of our approach. Experimental results show significant performance improvement over those obtained by previous
approaches. Our code is written using C and the Message Passing Interface (MPI). Thus, it is portable across various HPC platforms.
Received April 8, 1998; revised February 2, 1999. 相似文献
96.
一种基于DSP的雷达信号实时处理系统 总被引:1,自引:0,他引:1
介绍了在特定环境下使用的一种雷达信号实时处理系统的结构,工作原理与工作流程。 相似文献
97.
∶为高效开发老挝电源BOT项目,文章对老挝电源BOT项目的开发现状及实施步骤进行简介,并针对老挝电源BOT项目存在的风险,进行了策略性的讨论和研究,供同行们参考。 相似文献
98.
99.
一种新型ICA算法在RFID系统中的应用 总被引:1,自引:0,他引:1
针对无线射频识别系统在通信过程中的防碰撞问题,从信号处理的角度,提出一种基于盲源信号并行分离技术的防碰撞处理算法,其中包括信号白化技术,以及一种改进的独立元分析(ICA)信号并行分离方法.功能仿真结果证明,该算法的吞吐率最高达到69%,与吞吐率只有18%的传统Aloha算法相比,该算法能提高防碰撞能力. 相似文献
100.
森林保险市场的信号甄别和激励机制 总被引:5,自引:0,他引:5
基于森林保险市场存在的两种不确定因素,从减少道德风险和抑制逆向选择两方面出发,同时引入了免赔额和共保率,并对投保林主和森林进行综合风险分类,构建了一个信号甄别和激励模型,导出了一种符合森林保险市场发展需要的费率与共保率厘定体系.该方法打破了传统森林保险费率统一的定价模式. 相似文献