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排序方式: 共有601条查询结果,搜索用时 296 毫秒
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2.
基于域加权词频法的XML文档级检索实现与评价 总被引:1,自引:0,他引:1
利用BM25F模型,通过实验,在INEX 04数据集的基础上,实现了对多个域(元素)词频进行加权的XML文档级检索。XML文档结构的确蕴含了一定的语义信息。利用这些语义信息,可以提高检索性能。表2。图1。参考文献16。 相似文献
3.
Kinship,Camaraderie and Contestation: Fāṭimid Relations with the Ashrāf in the Fourth/Tenth Century.
Shainool Jiwa 《Al-Masaq: Islam & the Medieval Mediterranean》2016,28(3):242-264
The founding of the Fā?imid caliphate across the southern Mediterranean, and then in Egypt, Syria and the ?ijāz at the turn of the fourth/tenth century, necessitated its negotiation with the ashrāf, those who claimed lineal descent from the Prophet Mu?ammad, and who by this time had gained significant influence as a social class based on their charismatic descent. While other dynastic powers fostered relationships with various members of the ashrāf, the Fā?imid–ashrāf dynamics were distinctive in that the Fā?imids legitimised their rule as Ismā?īlī Shī?ī imām-caliphs, based on their claim of descent from the Prophet Mu?ammad, and as the sole successors to his authority and leadership over the Islamic world. Consequently, Fā?imid–ashrāf relations were permeated by fraternal camaraderie as well as by competing contestations based on their shared claim to Prophetic lineage. 相似文献
4.
数字信号处理(DSP)开放实验教学探讨 总被引:1,自引:1,他引:1
数字信号处理(Digital Signal Process,简称DSP)是利用专用或通用数字信处理芯片,通过数字计算的方法进行处理,TI公司提供的DSK(DSP STARTER KIT)套板是基于TMS320C5402数字信号处理器的DSP开发,教学实验系统,本文对利用这一系统开发的实验内容和实验教学方法等进行了详细的阐述。 相似文献
5.
山磊 《常熟理工学院学报》2006,20(4):97-99
介绍了基于PIC16F946 IC卡燃气表的设计、PIC16F946芯片的特点、给出了设计电路图和程序流程,对锈蚀问题进行了讨论并给出了采用模糊控制的解决方案。 相似文献
6.
Ronna F. Dillon 《Contemporary educational psychology》1985,10(4):387-395
The study reported herein was designed to use eye movement data, collected during solution of complex figural analogies, to test the premise that enhanced feedback mechanisms and opportunities for dual coding of figural stimulus information result in the allocation of an increased percentage of information-processing resources to rule application activities. Subjects were given items from the Advanced Progressive Matrices under elaborated feedback, subject verbalization, or standard procedures. Results indicate that elaborative testing conditions, involving elaborated feedback or subject verbalization, enhance the rule-governed nature of information processing during inductive reasoning by augmenting feedback and dual coding. 相似文献
7.
通过研究 G.729语音编码算法的原理,分析其基本特征及 DSP 体系结构特点,提出了一些有效的优化措施。在 TI的 TMS320C6713 DSK 平台上实现了该算法的编解码实验,结果证明其输出语音仍然保持了较高的合成品质 相似文献
8.
生命发展的非连续性及其教育--兼论博尔诺夫的非连续性教育思想 总被引:5,自引:0,他引:5
生命的发展是连续性和非连续性的统一,但以往教育学对人的发展的研究,注重的是发展的连续性,忽视了发展的非连续性.针对这一缺陷,本文论述了生命发展非连续性的原因以及它的教育形式,重点评述了博尔诺夫的非连续性教育思想. 相似文献
9.
花汉兵 《实验室研究与探索》2007,26(5):59-60,82
新型MSP430系列单片机具有低电压、超低功耗、丰富的片内外设和方便高效的开发环境等特点,典型应用于捕捉模拟信号的传感系统。并具体介绍了一种基于MSP430F449单片机的数据采集实验设计方法。此设计方案已经得到应用。 相似文献
10.
S. Negassi 《Research Policy》2004,33(3):365-384
The scope of this paper is to report new empirical evidence on the determinants of R&D co-operation. Indeed, the literature on the capabilities of firms emphasises the role of knowledge in the performance and evolution of firms who use knowledge developed in others to build their own knowledge capital. R&D co-operation between firms is one of the many strategies by which this knowledge may be transmitted. Several theoretical models have stressed that R&D co-operation is more likely when the level of spillovers is high. While this supposition is used in many theoretical models, it has rarely been tested before. Our results do not lend strong support to this intuition. Indeed, our spillover variables (national pure spillovers, national rent spillovers and imports of machine tools), which were supposed to match the theoretical notion of spillovers used in these theoretical models have a positive but not a significant role when explaining R&D co-operation. The R&D co-operation increases with size and with R&D intensity, but not with market share. It also increases with the budget spent on paying license fees and on acquiring patents and labour from foreign firms. In this study, we also analyse the determinants of innovation. In more precise terms, we compare the effects of R&D co-operation to those played by traditional internal factors and those exerted by external, pure and rent spillovers on the innovation capacity of the firms. Our results show that the commercial success of innovations of French firms depends mainly on size, market share, R&D intensity and human capital. Inward FDI from industrialised countries exerts a positive and significant effect. The finding highlights the important role of the absorptive capacity of firms. Spillover measurements, such as the acquisition of machine tools, foreign patents, licenses, and technological opportunities have a positive impact on innovation. 相似文献