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141.
Two hundred fifty-six pregnant women who had quit smoking were classified into the precontemplation (PC), contemplation (C), preparation (PA), or action (A) stages of change for postpartum smoking cessation based on a 3-item algorithm assessing personal goals, self-efficacy, and smoking behavior. Logistic regression and event history analyses indicated group differences in return to smoking at 6 weeks and 3, 6, and 12 months postpartum. The percentage of women who returned to postpartum smoking was highest in the precontemplation stage and decreased with each subsequent stage, that is, at 6 weeks 83% of PCs, 64% of Cs, 35% of PAs, and 24% of As had returned to smoking. Results lend support for the stages of change for postpartum smoking abstinence. Stage-based interventions may be developed to assist women in maintaining abstinence postpartum. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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143.
The corrosion of fuel cladding and structural materials by lead and lead-bismuth eutectic in the liquid state at elevated temperatures is an issue that must be considered when designing advanced nuclear systems and high-power spallation neutron targets. In this work, lead corrosion studies of molybdenum were performed to investigate the interaction layer as a function of temperature by X-ray absorption spectroscopy. In situ X-ray absorption measurements on a Mo substrate with a 3-6 μm layer of Pb deposited by thermal evaporation were performed at temperatures up to 900 °C and at a 15° angle to the incident X-rays. The changes in the local atomic structure of the corrosion layer are visible in the difference extended X-ray absorption fine structure and the linear combination fitting of the X-ray absorption near-edge structure to as-deposited molybdenum sample and molybdenum oxide (MoO2 and MoO3) standards. The data are consistent with the appearance of MoO3 in an intermediate temperature range (650-800 °C) and the more stable MoO2 phase dominating at high and low temperatures.  相似文献   
144.
By means of an apparatus featuring a set of suspended baited containers, search abilities of 4 capuchin monkeys (Cebus apella) were evaluated. The experiment featured different spatial configurations of the search space. Results showed that monkeys exhaustively searched 9 containers spatially distributed as a 3?×?3 matrix, a cross, a line, or a circle. Search efficiency was higher when the search space featured either a linear or circular arrangement of containers. When faced with a linear arrangement of containers, the subjects developed principled search trajectories from 1 end to the other of the linear array. This behavioral regulation was independent from search efficiency as measured by the amount of visits to containers already explored. The data suggest that monkeys use either the travel distance or the cognitive costs associated with unprincipled travel trajectories as currency for regulation. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
145.
Studies with tumor necrosis factor p55 receptor- and interleukin-6 (IL-6)-deficient mice have shown that IL-6 is required for hepatocyte proliferation and reconstitution of the liver mass after partial hepatectomy. The biological activities of IL-6 are potentiated when this cytokine binds soluble forms of its specific receptor subunit (sIL-6R) and the resulting complex interacts with the transmembrane signaling chain gp130. We show here that double transgenic mice expressing high levels of both human IL-6 and sIL-6R under the control of liver-specific promoters spontaneously develop nodules of hepatocellular hyperplasia around periportal spaces and present signs of sustained hepatocyte proliferation. The resulting picture is identical to that of human nodular regenerative hyperplasia, a condition frequently associated with immunological and myeloproliferative disorders. In high expressors, hyperplastic lesions progress with time into discrete liver adenomas. These data strongly suggest that the IL-6/sIL-6R complex is both a primary stimulus to hepatocyte proliferation and a pathogenic factor of hepatocellular transformation.  相似文献   
146.
    
Ohne ZusammenfassungMitteilung aus dem Städtischen Chemischen Untersuchungsamt in Mailand.  相似文献   
147.
Journal of Electronic Testing -  相似文献   
148.
In this paper we present an efficient data fetch circuitry to retrieve several operands from a n-way parallel memory system in a single machine cycle. The proposed address generation unit operates with an improved version of the low-order parallel memory access approach. Our design supports data structures of arbitrary lengths and different odd strides. The experimental results show that our address generation unit is capable of generating eight 32 − bit addresses every 6 ns for different strides when implemented on a VIRTEX-II PRO xc2vp30-7ff1696 FPGA device using only trivial hardware resources.
Georgi N. GaydadjievEmail:

Carlo Galuzzi   received the M.Sc. in Mathematics (summa cum laude) from Università Degli Studi di Milano, Italy in 2003. He is currently at the final stage of his Ph.D. in Computer Engineering at TU Delft, The Netherlands. He is a reviewer for more than 20 international conferences and journals. He served as publication chair for many conferences, e.g. MICRO-41, SAMOS 2006-08, DTIS 2007. His research interests include instruction-set extension, hardware-software partitioning and graph theory. Carlo received the best paper award at ARC 2008. Chunyang Gou   was born in Sichuan, China in 1981. He received the Bachelor degree from University of Electronic Science and Technology of China (UESTC), Chengdu, China in 2003 and the MSc degree from Tsinghua University, Beijing, China in 2006. He is currently working towards the Ph.D. in Computer Engineering in the Delft University of Technology, The Netherlands. His research interests include computer architecture in general, with particular emphasis on high-performance memory hierarchies. Humberto Calderón   was born in La Paz, Bolivia, in 1964. He received the M.Sc. degree in Computer Sciences from the ITCR (Costa Rica) in 1997 and the Ph.D. degree in computer engineering from TU Delft, The Netherlands, in 2007. His current research interests include reconfigurable computing, multimedia embedded systems, computer arithmetic, intelligent control and robotics. He currently joined the “Istituto Italiano di Tecnologia in Genova, Italy, as a senior engineer and researcher. Georgi N. Gaydadjiev   was born in Plovdiv, Bulgaria, in 1964. He is currently assistant professor at the Computer Engineering Laboratory, Delft University of Technology, The Netherlands. His research and development industrial experience includes more than 15 years in hardware and software design at System Engineering Ltd. in Pravetz Bulgaria and Pijnenburg Microelectronics and Software B.V. in Vught, the Netherlands. His research interests include: embedded systems design, advanced computer architectures, hardware/software co-design, VLSI design, cryptographic systems and computer systems testing. Georgi has been a member of many conference program committees at different levels, e.g. ISC, ICS, Computing Frontiers, ICCD, HiPC and more. He was program chair of SAMOS in 2006 and was a general chair in 2007. Georgi received the best paper awards at Usenix/SAGE LISA 2006 and WiSTP 2007. He is IEEE and ACM member. Stamatis Vassiliadis   (M’86-SM’92-F’97) was born in Manolates, Samos, Greece 1951. Regrettably, Prof. Vassiliadis deceased in April 2007. He was a chair professor in the Electrical Engineering department of Delft University of Technology (TU Delft), The Netherlands. He had also served in the EE faculties of Cornell University, Ithaca, NY and the State University of New York (S.U.N.Y.), Binghamton, NY. He worked for a decade with IBM where he had been involved in a number of advanced research and development projects. For his work he received numerous awards including 24 publication awards, 15 invention awards and an outstanding innovation award for engineering/scientific hardware design. His 72 USA patents rank him as the top all time IBM inventor. Dr. Vassiliadis received an honorable mention Best Paper award at the ACM/IEEE MICRO25 in 1992 and Best Paper awards in the IEEE CAS (1998, 2001), IEEE ICCD (2001), PDCS (2002) and the best poster award in the IEEE NANO (2005). He is an IEEE and ACM fellow and a member of the Royal Dutch Academy of Science.   相似文献   
149.
Wireless Personal Communications - The integration of everyday objects into the Internet represents the foundation of the forthcoming Internet of Things (IoT). Smart objects will be the building...  相似文献   
150.
Throughout the 1990s, Software Defined Radio (SDR) technology was viewed almost exclusively as a solution for interoperability problems between various military standards, waveforms and devices. In the meantime, Cognitive Radio (CR) – a novel communication paradigm which embodies SDR with intelligence and self-reconfigurability properties – has emerged. Intelligence and on-the-fly self-reconfiguration abilities of CRs constitute an important next step in the Communications Electronic Warfare, as they may enable the jamming entities with the capabilities of devising and deploying advanced jamming tactics. Similarly, they may also aid the development of the advanced intelligent self-reconfigurable systems for jamming mitigation. This work outlines the development and implementation of the Spectrum Intelligence algorithm for Radio Frequency (RF) interference mitigation. The developed system is built upon the ideas of obtaining relevant spectrum-related data by using wideband energy detectors, performing narrowband waveform identification, extracting the waveforms’ parameters and properly classifying the waveforms. All relevant spectrum activities are continuously monitored and stored. Coupled with the self-reconfigurability of various transmission-related parameters, Spectrum Intelligence is the facilitator for the advanced interference mitigation strategies. The implementation is done on the Cognitive Radio test bed architecture which consists of two military Software Defined Radio terminals, each interconnected with the computationally powerful System-on-Module.  相似文献   
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