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991.
Takatoshi Ohara Yasuhiro Akiyama Koji Nagata Hiroyuki Nitta Yasuyuki Kudo 《Journal of the Society for Information Display》2011,19(1):116-122
Abstract— The plasma‐display panel (PDP) is a type of flat‐panel display that can display a high‐quality image. However, when moving images are displayed, annoying disturbances such as false contour noise occurs. This noise is called dynamic false contour (DFC). To achieve a higher‐quality image, DFC has to be reduced. Therefore, a new method to reduce DFC is proposed. To find a way to reduce DFC, a new evaluation value for it has been defined: the evaluation value of dynamic false contour (EVDFC). This value is defined on the basis of a person's subjective evaluation. By applying this value, the cause that generates DFC can be identified. On the basis of these studies, a new method for reducing DFC by applying frame‐rate control (FRC) with suppression of the side effect is proposed. This improved method can be used to provide high‐quality images. 相似文献
992.
?pek Abas?kele? 《Computers & Electrical Engineering》2010,36(1):114-131
Recent advances in the development of optical technologies suggest the possible emergence of broadcast-based optical interconnects within cache-coherent distributed shared memory (DSM) multiprocessor architectures. It is well known that the cache-coherence protocol is a critical issue in designing such architectures because it directly affects memory latencies. In this paper, we evaluate via simulation the performance of three directory-based cache-coherence protocols; strict request-response, intervention forwarding and reply forwarding on the Simultaneous Optical Multiprocessor Exchange Bus (SOME-Bus), which is a low-latency and high-bandwidth broadcast-based fiber-optic interconnection network supporting DSM. The simulated system contains 64 nodes, each of which has a processor, a cache controller, a directory controller and an output channel. Simulations have been conducted for each protocol to measure average processor utilization, average network latency and average number of packets transferred over the network for varying values of the important DSM parameters such as the ratio of the mean channel service time to mean thread run time (T/R), probability of a cache block being in modified state {P(M)}, the fraction of write misses {P(W)} and home node contention rate. The results reveal that for all cases, except for low values of P(M), intervention forwarding gives the worst performance (lowest processor utilization and highest latency). The performance of strict request-response and reply forwarding is comparable for several values of the DSM parameters and contention rate. For a contention rate of 0%, the increase of P(M) makes reply forwarding perform better than strict request-response. The performance of all protocols decreases with the increase of P(W) and contention rate. However, the performance of strict request-response is the least affected among other protocols due to the negative impact of the increase of P(W) and contention rate. Therefore, for the full contention case (i.e. contention rate of 100%); for low values of P(M), or for mid values of P(M) and high values of P(W), strict request-response performs better than reply forwarding. These results are significant in the sense that they provide an insight to multiprocessor architecture designers for comparing the performance of different directory-based cache-coherence protocols on a broadcast-based interconnection network for different values of the DSM parameters and varying rates of contention. 相似文献
993.
Henrik Bærbak Christensen Author Vitae Klaus Marius Hansen Author Vitae 《Journal of Systems and Software》2010,83(1):133-142
Architectural prototyping is the process of using executable code to investigate stakeholders’ software architecture concerns with respect to a system under development. Previous work has established this as a useful and cost-effective way of exploration and learning of the design space of a system and in addressing issues regarding quality attributes, architectural risks, and the problem of knowledge transfer and conformance. However, the actual industrial use of architectural prototyping has not been thoroughly researched so far. In this article, we report from three studies of architectural prototyping in practice. First, we report findings from an ethnographic study of practicing software architects. Secondly, we report from a focus group on architectural prototyping involving architects from four companies. And, thirdly, we report from a survey study of 20 practicing software architects and software developers. Our findings indicate that architectural prototyping plays an important and frequent role in resolving problems experimentally, but less so in exploring alternative solutions. Furthermore, architectural prototypes include end-user or business related functionality rather than purely architectural functionality. Based on these observations we provide recommendations for effective industrial architectural prototyping. 相似文献
994.
Abbas Nayebi Author Vitae Hamid Sarbazi-Azad Author Vitae Gunnar Karlsson Author Vitae 《Journal of Systems and Software》2010,83(8):1310-1317
This paper investigates a class of mobile wireless sensor networks that are unconnected most of the times; we refer to them as delay-tolerant wireless sensor networks (DTWSN). These networks inherit their characteristics from both delay tolerant networks (DTN) and traditional wireless sensor networks. After introducing DTWSNs, three main problems in the design space of these networks are discussed: routing, data gathering, and neighbor discovery. A general protocol is proposed for DTWSNs based on opportunistic broadcasting in delay-tolerant networks with radio device on-off periods. Three performance measures are defined in the study: the energy for sending queries to ask for data from possible neighbors (querying energy), data transfer energy, and absorption time (delay). A simple yet accurate approximation for the data-transfer energy is proposed. An analytic model is provided to evaluate the querying energy per contact (epc). Simulation results for the data propagation delay show that the querying energy per contact measure obtained from the analytic model is proportional to the product of the querying energy and the delay. A practical rule of thumb for an optimal query interval in terms of delay and energy is derived from different parts of the study. 相似文献
995.
996.
现有选择性计算机性能评价方法主要使用基准程序评价方法,基准程序中各子程序的输出往往因为单位不同而无法进行进一步数据处理,同时基准程序评价方法广泛采用的权重和评分方法缺乏理论依据。针对该问题,提出基于佩奇排名(PageRank)的计算机性能评价方法,采用比较数据序列间相似性的方法产生邻接矩阵从而为各项评估功能计算PageRank得分。实验结果表明,该方法能客观反映目标计算机系统的性能。 相似文献
997.
根据模糊综合评判法应用的广泛性及现状,提出开发通用的模糊综合评判工具。通过分析需求,建立了系统的功能结构,并通过实例展示了系统的功能。该工具基于Web,利用它,可以针对不同评价问题迅速开发相应的评判系统,且适合群决策,方便而易于使用。 相似文献
998.
为更好地解决Web应用的安全问题,提出了基于Webdecoy的攻击行为特征提取模型.以具体的业务系统为基础,通过嵌入监控代码跟踪对业务系统的访问并获取探测攻击信息,并对获取信息进行归一化处理和属性划分,根据属性的动态比较得到攻击请求的相似性结构.最后对探测行为进行检测评估,对恶意行为给出报警,并通过实验结果验证了该模型的有效性. 相似文献
999.
基于Web的教学质量评价系统的设计与实现 总被引:1,自引:0,他引:1
为解决高校教师教学质量评价的网络化问题,在综合考虑数字化校园建设要求基础上,提出了基于Web的高校教师教学质量评价系统的功能要求和体系结构,设计了后台数据库系统和功能模块,保证了系统的实用性、兼容性和可扩展性.研究了面向数字化校园综合管理平台的公共数据采集技术和系统安全设计,有效地解决了教师教学质量评价系统与其它业务系统之间的融合问题和系统安全问题.测试结果表明了系统的有效性. 相似文献
1000.
冯社苗 《计算机工程与设计》2010,31(9)
为了正确评估我国省级区域物流的发展水平,在分析了影响区域物流发展因素的基础上,明确了评估区域物流发展水平的指标选取原则,构建了评价我国区域物流发展水平的指标体系,利用SAS统计软件的谱系聚类功能,应用谱系聚类法对中国大陆省级区域物流发展水平的相似程度进行了聚类分析.分析和研究结果表明,目前我国各区域物流业的发展水平基本上反映了该区域内的经济社会发展水平,聚类结果科学合理,可以指导我国区域物流发展战略的政策制定.最后针对区域物流发展战略提出了建议. 相似文献