基于OpenMP的星载SAR回波信号并行仿真     

苏宇  齐向阳 《中国科学院大学学报》2008,25(1):129-135

本文首先介绍了星载SAR回波信号仿真相关技术,包括星地空间几何模型、回波信号数学模型和距离频域脉冲相干法。在此基础上给出了一种星载SAR回波信号仿真方案,并详细给出了其仿真算法流程。然后通过对仿真算法流程的并行性分析,以并行编程标准OpenMP为基础对仿真算法进行了并行化。仿真实验结果证明了并行仿真算法的正确性和高效性。  相似文献   

叙事的聚焦与遮蔽——以抗战殉难叙事为例     

丁伯林 《滁州职业技术学院学报》2008,7(2):28-33

叙事聚焦与遮蔽决定于叙事立场.以叙事者的心灵之光将对象照亮,充分呈现对象在主体精神观照之下最为闪光的一面,此为聚焦;在主体精神观照之下,或受意识形态规约,将对象本应呈示的一面予以遮挡,让读者或观众无从知晓者,是为遮蔽.本文以抗战时期为国殉难名将的叙事文本为例.分析叙事者在叙事过程中是如何聚焦与遮蔽的.  相似文献   

中国古代天文档案遗存及其科技文化价值研究   总被引：1，自引：0，他引：1  

丁海斌  刘维贵 《档案学研究》2008,22(4):18-21

自有文明史以来,中国就设有专门机构或人员进行天象观测与研究,并形成天文档案.它主要有两大类:一是天文观测记录及其所形成的星图星经等;二是历书档案.历代绵延不辍的天学机构既是天文档案的形成者又是主要管理者,其良好的保管制度和各朝天文史志的编研为我们留下了数量可观的天文档案遗存,它可分为两大类:直接遗存与间接遗存.  相似文献   

基于本体的智能数字图书馆个性化推荐用户本体研究     

丁雪  张玉峰 《现代情报》2009,29(12):61-65,71

针对目前传统数字图书馆无法为用户提供准确个性化服务的问题,提出通过本体构建智能数字图书馆,并且分析如何通过本体的作用使传统的数字图书馆达到智能个性推荐的基本原理,最后重点分析基于本体的个性推荐中的关键性问题,即用户本体的构建——读者用户本体库,包括用户基本信息本体、用户个性本体和用户需求本体,并用六元组表示方法实践本体的表示,以及通过流程图诠释本体间的作用机制。  相似文献   

Relationships with supply chain partners affecting internal operation of high-tech manufacturers in Taiwan     

Kris M.Y.   《The Journal of High Technology Management Research》2009,20(1):31-39

The increasing number of interactions between Taiwan and the Mainland may bring in both opportunities and competitions among the companies in the region. Companies are forced to continuously change and develop to advance and to sustain in the competitive environment. It also holds true for the companies in the even more competitive high-tech industries. It is therefore of a value to study what challenges the high-tech firms are facing, how these challenges impact on their performance and how these firms are dealing with issues. Among the multiple challenges, supply chain operation has been a critical issue concerning the high-tech manufacturers.The purpose of this study is to investigate the relationships between the various supply chain operation determinants (relationships with business partners, internal operation) and the impacts of relationships with supply chain partners on the internal operation and the collective efficacy relating to the scheduling issues in high-tech manufacturing firms in Taiwan. A research framework linking internal operation and relationships with supply chain partners (supplier and customer) and individuals (perceived collective efficacy) is applied.  相似文献   

The determinants of academic research commercial performance: Towards an organizational ambidexterity perspective     

Yuan-Chieh Chang  Phil Y. Yang  Ming-Huei Chen 《Research Policy》2009,38(6):936-946

This paper examined the relationship between organizational ambidexterity and research commercialization in universities. The paper develops two types of organizational ambidexterity: structural ambidexterity and contextual ambidexterity that influence research commercialization. Through a dataset of 474 academic patent inventors in Taiwan, the results revealed structural and contextual ambidexterity factors are patenting-, licensing- and start-up-specific. Despite both types of ambidexterity are complementary in patenting and licensing, contextual ambidexterity outperform structural ambidexterity in fostering university start-up equity participation. To promote academic research commercialization, it is necessary to build up a university as a dual structural organization that allows pursuing research excellence and research commercialization at the same time.  相似文献   

A security-embedded infrastructure for Tele-Traffic Speed Control     

Mohammed A. Khasawneh  Mohammad I. Malkawi  Sa’ed M. Hayajneh  Hadeel Y. Qasaimeh 《Journal of The Franklin Institute》2009,346(5):431-448

In this paper we introduce a novel approach, relying on intelligent engineering, whereby the maximum speed limit at which vehicles on the road can cruise is controlled from some central or distributed facility. The system, as designed, leverages the use of the ubiquitous cellular infrastructure to cut down the costs involved that would otherwise accrue as a result of the need to build a dedicated traffic control system.In the new system maximum speed limits are transmitted from a Central Control Facility (CCF) to all stretches of roads and highways dispersed across urban areas in a highly dynamic manner. The system uses information arriving via a dynamic feedback system on prevailing weather conditions, road conditions, and bulk of traffic, amongst others, before it would broadcast maximum speed limit information to various destinations. When deployed in its final release, this will be done using a highly automated system with little human intervention.The work presented in this paper elaborates the TTC Network Design and RSU Network Distribution for the Tele-Traffic Speed Control System, to remotely manage, enforce, and control the maximum speed limit allowed on road stretches in rural and urban areas for different vehicle categories.The new system has been deployed successfully in a laboratory controlled environment on three vehicle categories; one category representing passenger vehicles, another buses and commuter transport, while the third representing trucks and freight traffic. It is expected that when the system is fully deployed on the wireless infrastructure, speed-related traffic accidents will witness a drop by more than 65-70% according to known accident statistics.  相似文献   

Innovation strategy and performance during economic transition: Evidences in Beijing, China   总被引：1，自引：0，他引：1  

Jian Cheng GUAN Author Vitae  Esther P.Y. Tang Author Vitae 《Research Policy》2009,38(5):802-812

This paper evaluates the relevance of innovation strategy to various categories of Chinese firms and investigates its relationship with innovation performance during the economic transition of the 1990s. Data from 1244 Chinese firms in Beijing are used to ascertain the relative importance of different innovation objectives, along with the innovation strategies adopted by manufacturing firms. Results show that innovation activities were confined to the domestic sphere and mainly directed at quality improvement. Chinese manufacturing firms which obtained support from the government through the high-tech firm accreditation system generally perform better. They had already started moving away from a reliance on imported technology and equipment, and using indigenous R&D efforts to innovate for the coming market economy.  相似文献   

经济危机与社会脆弱带   总被引：1，自引：1，他引：0  

李丁 《科学对社会的影响》2009,(1):10-14

2007年以来的金融海啸最终酿成一场严重的经济危机,这场危机给发展中的中国带来了诸多问题。在这场危机中,农民工的生存环境和发展条件受到了很多研究者的重视。本文借用生态学中生态脆弱带的概念,综合应用经济学中的。一些模型,分析造成当前大量农民工流动的原因,并结合经济危机所带来的巨大困难,分析社会脆弱带所必须要面对的诸多问题,得出只要政府注意调整收入再分配和公共服务的比例,将不会造成社会动荡的结论。最后,对如何针对经济危机与收入差异构建和谐社会提出了相应的政策建议。  相似文献   

Why the whole is less than the sum of its parts: Examining knowledge management in acquisitions     

Alton Y.K. Chua  Dion H. Goh 《International Journal of Information Management》2009

This paper seeks to explain why an acquiring organization was unable to leverage the expertise of the acquired organization even though both organizations were highly successful in their own right prior to the acquisition. It offers a knowledge-based perspective by teasing out the essential knowledge attributes pertinent to acquisitions. The research was carried out using an interpretative case study methodology at a Singapore-based multinational organization in the semi-conductor industry. The main data collection method used was face-to-face interviews with some 28 staff from October 2006 to December 2006, almost 2 years after the acquisition exercise. The findings suggest that the lackluster outcome could be traced to three knowledge attributes, namely, accessibility, applicability and cumulativeness. In conclusion, a number of practical and research implications are highlighted.  相似文献