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941.
The effects of physical refining on the formation of 3-monochloropropane-1,2-diol esters in relation to palm oil minor components 总被引:2,自引:0,他引:2
The formation of 3-monochloropropane-1,2-diol (3-MCPD) esters in refined palm oil during deodorisation is attributed to the intrinsic composition of crude palm oil. Utilising D-optimal design, the effects of the degumming and bleaching processes on the reduction in 3-MCPD ester formation in refined palm oil from poor-quality crude palm oil were studied relative to the palm oil minor components that are likely to be their precursors. Water degumming remarkably reduced 3-MCPD ester formation by up to 84%, from 9.79 mg/kg to 1.55 mg/kg. Bleaching with synthetic magnesium silicate caused a further 10% reduction, to 0.487 mg/kg. The reduction in 3-MCPD ester formation could be due to the removal of related precursors prior to the deodorisation step. The phosphorus content of bleached palm oil showed a significant correlation with 3-MCPD ester formation. 相似文献
942.
Sincereformandopeningtotheoutsideworld,China'stextileindustryhasa chievedrapiddevelopment.Especiallyinrecentyears,wehavewitnessedsignif icantimprovementintermsofvolume,quality,varieties,efficiency,earningsofforeigncurrency,fiberconsumptionper capita,and… 相似文献
943.
A system design method of thermoelectric cooler is developed in the present study. The design calculation utilizes the performance curve of the thermoelectric module that is determined experimentally. An automatic test apparatus was designed and built to illustrate the testing. The performance test results of the module are used to determine the physical properties and derive an empirical relation for the performance of thermoelectric module. These results are then used in the system analysis of a thermoelectric cooler using a thermal network model. The thermal resistance of heat sink is chosen as one of the key parameters in the design of a thermoelectric cooler. The system simulation shows that there exists a cheapest heat sink for the design of a thermoelectric cooler. It is also shown that the system simulation coincides with experimental data of a thermoelectric cooler using an air-cooled heat sink with thermal resistance 0.2515°C/W. An optimal design of thermoelectric cooler at the conditions of optimal COP is also studied. The optimal design can be made either on the basis of the maximum value of the optimal cooling capacity, or on the basis of the best heat sink technology available. 相似文献
944.
Modeling and Simulation for Transient Thermal Analyses Using a Voltage-in-Current Latency Insertion Method 下载免费PDF全文
This article presents a modeling and simulation method for transient thermal analyses of integrated circuits(ICs) using the original and voltage-in-current(VinC) latency insertion method(LIM). LIM-based algorithms are a set of fast transient simulation methods that solve electrical circuits in a leapfrog updating manner without relying on large matrix operations used in conventional Simulation Program with Integrated Circuit Emphasis(SPICE)-based methods which can significantly slow down the sol... 相似文献
945.
David N. Chin 《Artificial Intelligence Review》2000,14(4-5):283-331
Intelligent help systems cannot merely respond passively to the user'scommands and queries. They need to be able to volunteer information,correct user misconceptions, and reject unethical requests when appropriate.In order to do these things, a system must be designed as an intelligentagent. That is, a system needs to have its own goals and then plan forthese goals. A system which did not have its own goals would never refuseto help users perform unethical actions.Such an intelligent agent has been implemented in the UCEgo component of UC(Wilensky et al. 1984; Wilensky et al. 1988) (UNIX Consultant), a natural languagesystem that helps the user solve problems in using the UNIX operatingsystem. UCEgo provides UC with its own goals and plans. By adoptingdifferent goals in different situations, UCEgo creates and executesdifferent plans, enabling it to interact appropriately with the user.UCEgo adopts goals when it notices that the user either lacks necessaryknowledge, or has incorrect beliefs. In these cases, UCEgo plans tovolunteer information or correct the user's misconception as appropriate.These plans are pre-stored skeletal plans that are indexed under the types ofsituations in which they are typically useful. Plan suggestion situationsinclude the goal which the plan is used to achieve, the preconditions of theplan, and appropriateness conditions for the plan. Indexing plans bysituations improves efficiency and allows UC to respond appropriately to theuser in real time.Detecting situations in which a plan should be suggested or a goal adoptedis implemented using if-detected daemons. These daemons provide asingle mechanism which can be used both for detecting goals and suggestingplans. Different methodologies for the efficient implementation ofif-detected daemons are discussed. 相似文献
946.
A variety of peer-to-peer (P2P) systems for sharing digital information are currently available and most of them perform searching by exact key matching. In this paper we focus on similarity searching and describe FuzzyPeer, a generic broadcast-based P2P system which supports a wide range of fuzzy queries. As a case study we present an image retrieval application implemented on top of FuzzyPeer. Users provide sample images whose sets of features are propagated through the peers. The answer consists of the top-k most similar images within the query horizon. In our system the participation of peers is ad hoc and dynamic, their functionality is symmetric and there is no centralized index. 相似文献
947.
Analysis of thinning algorithms using mathematical morphology 总被引:9,自引:0,他引:9
Jang B.-K. Chin R.T. 《IEEE transactions on pattern analysis and machine intelligence》1990,12(6):541-551
A precise definition of digital skeletons and a mathematical framework for the analysis of a class of thinning algorithms, based on morphological set transformation, are presented. A particular thinning algorithm (algorithm A) is used as an example in the analysis. Precise definitions and analyses associated with the thinning process are presented, including the proof of convergence, the condition for one-pixel-thick skeletons, and the connectedness of skeletons. In addition, a necessary and sufficient condition for the thinning process in general is derived, and an algorithm (algorithm B) based on this condition is developed. Experimental results are used to compare the two thinning algorithms, and issues involving noise immunity and skeletal bias are addressed 相似文献
948.
使用朴素的贝叶斯(NB)分类模型对邮件进行分类,是目前基于内容的垃圾邮件过滤方法的研究热点。朴素的贝叶斯在参数之间联系不强的时候分类效果简单而有效。但是朴素的贝叶斯分类模型中对特征参数的条件独立假设无法表达参数之间在语义上的关系,影响分类性能。在朴素的贝叶斯分类模型的基础上,我们提出了一种双级贝叶斯分类模型(DLB,Double Level Bayes),既考虑到了参数之间的影响又保留了朴素的贝叶斯分类模型的优点。同时时DLB模型与朴素的贝叶斯分类模型的性能进行比较。仿真实验表明,DLB分类模型在垃圾邮件过滤应用中的效果在大部分条件下优于朴素的贝叶斯分类模型。 相似文献
949.
Bharadwaj Veeravalli Long Chen Hun Yen Kwoon Goh Kar Whee See Ying Lai Lim Peng Hian Ho Chin Chow 《Multimedia Tools and Applications》2006,28(1):89-118
The problem of employing multiple servers to serve a pool of clients on a network based multimedia service is addressed. We
have designed and practically implemented a prototype system employing multiple servers to render a long duration movie to
the customers. We have employed a multiple server retrieval strategy proposed in the literature [39] to realize this system.
In the system, server coordination, client behavior and service facilities are completely controlled by an Agent based approach
in which we have used the recent Jini technology. Several issues, ranging from data retrieval from individual server, behavior
of the underlying network infrastructure, to client management and resource (client buffers) management, are considered in
this implementation. We describe in detail our experiences in this complete design process of every module in the software
architecture, its purpose, and working style. Further, the system is shown to be robust amidst unpredictable failures, i.e.,
in the event of server crashes. The load balancing capability is built-in as a safe guard measure to assure a continuous presentation.
We present a comprehensive discussion on the software architecture to realize this working system and present our experiences.
A system comprising a series of Pentium III PCs on a fast Ethernet network is built as a test-bed. Through this prototype,
a wider scope of research challenges ahead are highlighted as possible extensions.
Bharadwaj Veeravalli Member, IEEE & IEEE-CS, received his BSc in Physics, from Madurai-Kamaraj Uiversity, India in 1987, Master's in Electrical
Communication Engineering from Indian Institute of Science, Bangalore, India in 1991 and PhD from Department of Aerospace
Engineering, Indian Institute of Science, Bangalore, India in 1994. He did his post-doctoral research in the Department of
Computer Science, Concordia University, Montreal, Canada, in 1996. He is currently with the Department of Electrical and Computer
Engineering, Computer and Information Engineering (CIE) division, at The National University of Singapore, Singapore, as a
tenured Associate Professor. His main stream research interests include, Multiprocessor systems, Cluster/Grid computing, Scheduling
in parallel and distributed systems, Bioinformatics & Computational Biology, and Multimedia computing. He is one of the earliest
researchers in the field of divisible load theory. He has published over 75 papers in high-quality International Journals
and Conferences. He had secured several externally funded projects. He has co-authored three research monographs in the areas
of Parallel and Distributed Systems, Distributed Databases, and Multimedia systems, in the years 1996, 2003, and 2005, respectively.
He had guest edited a special issue on Cluster/Grid Computing for IJCA, USA journal in 2004. He has been recently invited
to contribute to Multimedia Encyclopedia, Kluwer Academic Publishers, 2005. He is currently serving the Editorial Board of
IEEE Transactions on Computers, IEEE Transactions on SMC-A and International Journal of Computers & Applications, USA, as an Associate Editor. He had served as a program committee member and as a session chair in several International Conferences.
Long Chen received the B.E. degree in Electrical Engineering and M.E. degree in Electrical Engineering from the Northwestern Polytechnic
University, P. R. China, in 1998 and 2001, respectively, and the M.E. degree in Computer Engineering from the National University
of Singapore, Singapore, in 2004. He is currently a Ph.D. candidate at the Department of Electrical and Computer Engineering,
the University of Delaware, United States. His research interests include multimedia systems, distributed system, network
security, and computer architecture. 相似文献
950.
Su Chen Beng Chin Ooi Zhenjie Zhang 《The VLDB Journal The International Journal on Very Large Data Bases》2012,21(2):265-286
In the last decade, spatio-temporal database research focuses on the design of effective and efficient indexing structures
in support of location-based queries such as predictive range queries and nearest neighbor queries. While a variety of indexing
techniques have been proposed to accelerate the processing of updates and queries, not much attention has been paid to the
updating protocol, which is another important factor affecting the system performance. In this paper, we propose a generic
and adaptive updating protocol for moving object databases with less number of updates between objects and the database server,
thereby reducing the overall workload of the system. In contrast to the approach adopted by most conventional moving object
database systems where the exact locations and velocities last disclosed are used to predict their motions, we propose the
concept of Spatio-temporal safe region to approximate possible future locations. Spatio-temporal safe regions provide larger space of tolerance for moving objects,
freeing them from location and velocity updates as long as the errors remain predictable in the database. To answer predictive
queries accurately, the server is allowed to probe the latest status of objects when their safe regions are inadequate in
returning the exact query results. Spatio-temporal safe regions are calculated and optimized by the database server with two
contradictory objectives: reducing update workload while guaranteeing query accuracy and efficiency. To achieve this, we propose
a cost model that estimates the composition of active and passive updates based on historical motion records and query distribution.
More system performance improvements can be obtained by cutting more updates from the clients, when the users of system are
comfortable with incomplete but accuracy bounded query results. We have conducted extensive experiments to evaluate our proposal
on a variety of popular indexing structures. The results confirm the viability, robustness, accuracy and efficiency of our
proposed protocol. 相似文献