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81.
In this paper, we present a visionary concept referred to as Collaborative and Cognitive Network Platforms (CCNPs) as a future-proof solution for creating a dependable, self-organizing and self-managing communication substrate for effective ICT solutions to societal problems. CCNP creates a cooperative communication platform to support critical services across a range of business sectors. CCNP is based on the personal network (PN) technology which is an inherently cooperative environment prototyped in the Dutch Freeband PNP2008 and the European Union IST MAGNET projects. In CCNP, the cognitive control plane strives to exploit the resources to better satisfy the requirements of networked applications. CCNP facilitates collaboration inherently. Through cognition in the cognitive control plane, CCNP becomes a self-managed substrate. The self-managed substrate, in this paper, is defined as cognitive and collaborative middleware on which future applications run without user intervention. Endemic sensor networks may be incorporated into the CCNP concept to feed its cognitive control plane. In this paper, we present the CCNP concept and discuss the research challenges related to collaboration and cognition.  相似文献   
82.
Traditional input indicators of research performance, such as research funding, number of active scientists, and international collaborations, have been widely used to assess countries’ publication output. However, while publication in today’s English-only research world requires sound research in readable English, English proficiency may be a problem for the productivity of non-native English-speaking (NNES) countries. Data provided by the Brazilian National Research Council (CNPq) containing the academic profile of 51,223 Brazilian researchers show a correlation between English proficiency and publication output. According to our results, traditional input indicators may fall short of providing an accurate representation of the research performance of NNES developing countries.  相似文献   
83.
A dearth of literature exists on barriers to conducting research with Black male victims of community violence, despite the need for evidence-based postinjury interventions. This study used qualitative data from a cross-sectional interview study (n = 16) and a pilot intervention study (n = 11) conducted in Boston, MA to identify challenges and facilitators to conducting research with Black male victims of community violence, particularly with regard to recruitment and maintenance of a study sample. Qualitative methods, including Grounded Theory and ethnography, were used to analyze the data. Challenges included a fear of police involvement, an impression of “snitching” when disclosing personal information, mistrust of research motives, suspicion of the informed consent process, the emotional impact of the trauma itself, and logistical issues. Facilitators to research included monetary incentives and motivation to help oneself and others. Participant recommendations on recruitment methods relating to approach and timing are provided. Findings from this study may assist in the planning of research studies for Black male victims of community violence. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
84.
ABSTRACT: This study investigated the effects of temperature (15 to 37 °C) and water activity (0.90 to 0.99) on the growth and production of ochratoxin A (OTA) by Aspergillus carbonarius cultured on synthetic nutrient medium (SNM) after 5 and 10 d of incubation. Total of 8 ochratoxigenic A. carbonarius, isolated from vineyards located in different regions of Tunisia, were used. Growth data were modeled by the flexible model of Baranyi and growth rates at each set of conditions were obtained. For both growth and OTA production, optimal water activity was 0.99; however, optimal temperature varied. The optimal temperature for growth was 30 °C. At 37 °C, the growth rate decreased significantly (P < 0.05). Maximum toxin production occurred at temperatures in the range of 15 to 25 °C with the optimum one depending on the isolate tested. Significant amounts of OTA were produced after only 5 d of incubation. Our results showed that A. carbonarius isolated from Tunisian grapes behave as those from European and Australian grapes, as reported in the literature, although some differences in trends for growth and OTA production were observed.  相似文献   
85.
A three-phase model of asynchronous machines operating at medium or high frequencies is presented. It can be used to study the propagation of surge waves along the stator windings of induction form wound machines.The model is derived from an analogy with a three-phase transmission line. The use of time-space Clarke vectors allows the introduction of mutual coupling between phases. The analytical expressions for voltage waves are derived by means of the Laplace approach to the solution of hyperbolic partial differential equations.Some applicative examples confirm the model validity and can underline some aspects of the project of three-phase windings.  相似文献   
86.
Lanthanum chromite (LaCrO3) is currently the most widely studied material as interconnector layers for solid oxide fuel cells (SOFC). The complexity of microstructures and geometries of SOFC devices, which are usually built-up by lamination of the different constitutive layers, make it necessary a precise control of processing parameters to achieve the desired combination of properties. Much effort has been devoted to the processing of electrodes and electrolytes but the other layers, such as that of interconnecting material, have received scarce attention. This work deals with the preparation and optimisation of the rheological behaviour of concentrated suspensions of Sr- and Co-doped LaCrO3 and the subsequent tape casting to produce homogeneous thin sheets to be used in the SOFC stack.The starting powder was produced by combustion synthesis from the corresponding nitrates and urea as a fuel, and had a final composition of La0.80Sr0.20Cr0.92Co0.08O3. These powders were dispersed in ethanol with commercial copolymers (Hypermer, KD6) to solids loading of up to 58 wt%. The binding system (BS) consisted of a mixture of a binder, polyvinyl butyral-co-vinyl alcohol-co-vinyl acetate (PVA-PVAc), and two plasticizers, polyethyleneglycol (PEG400) and benzylbutylphthalate (BBP). The effect of the binding system content and the binder-to-plasticizer ratio on the tape casting performance and the characteristics of the green and the sintered tapes, were studied, as well as the influence of the casting parameters (casting speed and blades height).  相似文献   
87.
On the Mediation of Everything: ICA Presidential Address 2008   总被引:1,自引:0,他引:1  
As our field moves beyond the traditional dualism of mass and interpersonal forms of communication to encompass new, interactive, networked forms of communication whose influence may be traced across multiple spheres of modern life, it is commonly claimed that "everything is mediated" and that this represents a historically significant change. This article inquires into these rhetorically grand claims: first, noting the parallels with other processes of mediation (e.g., language, money, and myths); second, raising questions of value since, unlike for other forms of mediation, the media's role is typically construed as negative rather than positive; and third, observing that the difficulties of translating "mediation" into a range of languages reveals some conceptual confusions. As a step toward clarification, I contrast the terms "mediation" and "mediatization," these roughly mapping onto situational and historical influences, conceived primarily at micro- and macrolevels of analysis, respectively. I then argue for a broad conception of mediation that encompasses those processes variously referred to as "mediatization,""mediazation," or "medialization." The analysis is illustrated by unpacking the claim that "childhood is mediated," before concluding that distinct aspects of the concept of mediation invite communication scholars to attend to the specific empirical, historical, and political implications of the claim that "everything is mediated."  相似文献   
88.
Contera SA  Iwasaki H 《Ultramicroscopy》2002,91(1-4):231-243
We have applied scanning tunnelling microscopy (STM) to the study of two proteins: pseudoazurin and apo-pseudoazurin. Both proteins adsorbed onto a Au (1 1 1) surface are visible to STM individually, forming into layers and multilayers, with currents from about 55 to 600 pA. The images reproduce well the expected dimensions laterally but not in the z direction. The apparent height of the proteins varies with the voltage polarity, being higher at negative sample voltages. The bias also affects their shape. Negative sample voltages of more than 1.5 V orient the proteins present on a gold terrace in parallel rows. The layer of water adsorbed on surfaces in ambient conditions can be related to our results to explain the reduced z dimensions, the asymmetry with the voltage polarity and the alignment of proteins at voltages more negative than -1.5 V.  相似文献   
89.
An image can be seen as an element of a vector space and hence it can be expressed in as a linear combination of the elements of any non necessarily orthogonal basis of this space. After giving a matrix formulation of this well-known fact, this paper presents a reconstruction method of an image from its moments that sheds new light on this inverse problem. Two main contributions are presented: (a) the results using the standard approach based on the least squares approximation of the result using orthogonal polynomials can also be obtained using matrix pseudoinverses, which implies higher control on the numerical stability of the problem; and (b) it is possible to use basis functions in the reconstruction different from orthogonal polynomials, such as Fourier or Haar basis, allowing to introduce constraints relative to the bandwidth or the spatial resolution on the image to be reconstructed. Judit Martònez received the B.Sc. degree in 1993 and the PhD degree (with honors) in 1998, both in telecommunications engineering from the Technical University of Catalonia. She developed her research at the Institut de Robútica i Informütica Industrial of the Spanish High Council for Scientific Research. In 1999 she joined the Computer Vision Center, a R&D center founded by the Autonomous University of Barcelona and the Autonomous Government of Catalonia. She has been principal researcher of several industrial and research projects related to computer vision technologies. Her research interests include industrial applications of machine vision, efficient algorithms for low-level image processing, multiresolution mathematical models, statistical clustering, pattern classification and inverse problems. Josep M. Porta received the Engineer Degree in Computer Science in 1994 and the Ph.D. in Artificial Intelligence in 2001, both from the Technical University of Catalonia (UPC). After that, he joined the IAS group of the University of Amsterdam and currently, he holds a post-doc position at the Institut de Robútica i Informütica Industrial (CSIC-UPC) in Barcelona. He carried research in legged robots, machine learning, vision-based methods for autonomous robot localization, and computational kinematics. Federico Thomas is Research Professor at the Spanish Scientific Research Council (CSIC) and director of the Institut de Robútica i Informütica Industrial (CSIC-UPC), Barcelona, Spain. He received the telecommunications engineering degree in 1984, and the Ph.D. degree (with honors) in computer science in 1988, both from the Technical University of Catalonia (UPC). In 1991, he won a NATO postdoctoral scholarship at the University of Massachusetts with the late Prof. Robin Popplestone. In 1999, he was visiting professor, sponsored by the Autonomous Government of Catalonia, at the Oxford University Computing Laboratory with Prof. Stephen Cameron. He has been project leader of several national projects financed by the Spanish Committee for Science and Technology (CICYT), and by local companies such as ENHER, a power generation company now part of ENDESA. His current research interests are in Geometry and Kinematics with applications to Robotics, Computer Graphics and Computer Vision. Prof. Thomas is an Associate Editor of the IEEE Transactions on Robotics.  相似文献   
90.
Wireless networks are characterized by simple end devices and limited bandwidth. One solution to address these and other limitations of the wireless mobile environment that has been widely pursued is the placement of proxies, or agents, inside the network to assist with application processing that would normally take place on end devices. These agents can additionally manipulate data to reduce bandwidth requirements and assist in providing services. The design and implementation of a user agent is heavily impacted by the application it supports. In this paper we present our experiences with user agents in two different types of applications: telephony-based Personal Communication Services (PCS) and two-way messaging. To provide low latency service, the PCS user agents are mobile so that they may be kept close to their end devices. The design of the PCS agents limits migration overhead to the transfer of approximately 100 bytes of information in about 150 milliseconds. To provide advanced messaging services, the messaging user agent supports flexible messages while limiting air interface bandwidth usage. The messaging agents reduce uplink bandwidth usage by approximately 35% when applied to a cellular PCS system, and reduce message payloads by 97%. This revised version was published online in June 2006 with corrections to the Cover Date.  相似文献   
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