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91.
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This paper presents a combined statistical model for probationer risk classification and nonlinear multi-criteria programming resource allocation model for workload balancing. A statistical model of individual probationer failure was used to classify individuals as high, medium or low risk for probation purposes. The proportion of probationers in each risk category was used as an input into the integer, nonlinear resource allocation model where the decision variables were the number of visits to probationers by type of visit and risk classification.  相似文献   
93.
The effects of matrix ductility upon mechanisms of rubber toughening have been studied in a set of materials having identical rubber contents, but differing in matrix composition. The materials were made by solution blending 50% of HIPS (high-impact polystyrene) with polystyrene and PPO® poly-(2, 6-dimethyl-1, 4-phenylene oxide) in varying proportions. Crazing was studied quantitatively by measuring volume changes during creep. Analysis showed that in blends of HIPS with polystyrene, crazing is the only significant mechanism of tensile creep, whereas in blends containing polyphenylene oxide, shearing mechanisms are also important, and the contribution of crazing to creep deformation can be as low as 30%, depending upon matrix composition. Scanning electron microscopy showed that both crazes and shear bands were present in strained HIPS/PPO blends. Shear band formation appears to be responsible for the increased fracture resistance of blends containing a high proportion of polyphenylene oxide. A theory of toughening is proposed for these blends.  相似文献   
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The past 5 years of research with the adult Wechsler scales is critically reviewed. Most investigators used the most recently developed scale, the Wechsler Adult Intelligence Scale. Topical coverage includes: comparative validity; short forms; special populations and applications; refinements and critiques; personality correlates; investigations of diagnostic value; special diagnostic groups; and scatter, patterns, and diagnosis. The 197 articles reviewed show that there is no diminution in the number of researches in the area. While the quality of the research has improved, too many investigators repeat the errors contained in earlier studies, despite the periodic publication of these critical reviews. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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Correspondence     
The Editor does not hold himself responsible for opinions expressed by correspondents Textile Auxiliaries and the Journal  相似文献   
96.
This paper presents a low cost test method for the static and dynamic characterization of analog-to-digital converters. The method is suitable for implementation in a SoC environment, as a built-in self test (BIST) solution. In the proposed approach, noise is used as the test signal. Theory of operation and practical results demonstrating the effectiveness of the method for INL, DNL, THD and SINAD characterization are presented. The BIST surface overhead caused by the noise generator is only 7.4% of the ADC total area. The reduced number of data samples required allows a reduction of about 7.5× in test time, in comparison to the histogram method.Maria da Gloria Cataldi Flores was born in Santa Maria, Brazil, in 1978. She received the electrical engineering degree in 2000 from Universidade Federal de Santa Maria (UFSM) and the M.S. degree engineering in 2003 from Universidade Federal do Rio Grande do Sul (UFRGS), Brazil. Since then, she has been working as a design engineer in an EAS Supply brazilian company. Her main research interests include mixed-signal and analog testing and digital signal processing.Marcelo Negreiros was born in Porto Alegre, Brazil, in 1969. He received the electrical engineering degree in 1992 and the M.S. degree engineering in 1994, both from Universidade Federal do Rio Grande do Sul (UFRGS), Brazil. Since then he was been working as an associate researcher in the Signal Processing Lab. (LaPSI) of the Electrical Engineering Department at UFRGS. Since 2000 he also works toward a Ph.D. in Computer Science from UFRGS. His main research interests include mixed-signal and analog testing and digital signal processing.Luigi Carro was born in Porto Alegre, Brazil, in 1962. He received the Electrical Engineering and the M.Sc. degrees from Universidade Federal do Rio Grande do Sul (UFRGS), Brazil, in 1985 and 1989, respectively. From 1989 to 1991 he worked at ST-Microelectronics, Agrate, Italy, in the R&D group. In 1996 he received the Ph.D. degree in the area of Computer Science from Universidade Federal do Rio Grande do Sul (UFRGS), Brazil. He is presently a lecturer at the Electrical Engineering Department of UFRGS, in charge of Digital Systems Design and Digital Signal processing disciplines at the graduate and undergraduate level. He is also a member of the Graduation Program in Computer Science of UFRGS, where he is responsible for courses in Embedded Systems, Digital Signal Processing, and VLSI Design. His primary research interests include mixed-signal design, digital signal processing, mixed-signal and analog testing, and fast system prototyping. He has published more than 90 technical papers in those topics and is the author of the book Digital Systems Design and Prototyping (in portuguese).Altamiro A Susin was born in Vacaria-RS, Brazil, in 1945. He received the Electrical Engineering and the MSc. degrees from Universidade Federal do Rio Grande do Sul (UFRGS), Brazil, in 1972 and 1977, respectively. Since 1968 he worked in the start up of Computer Centers of two local Universities. In 1981 he got his Dr. Eng degree from Institut National Polytechnique de Grenoble-France. He is presently a lecturer at the Electrical Engineering Department of UFRGS, in charge of Digital Systems Design disciplines at the graduate and undergraduate level. He is also a member of the Graduation Program in Computer Science of UFRGS, where he is responsible by courses in VLSI Architecture and is also thesis director. His main research interests are Integrated Circuit Architecture, Embedded Systems, Signal Processing with more than 50 technical papers published in those domains. He is/was responsible for several R&D projects either funded with public and/or industry resources.Felipe Ricardo Clayton received the B.S. degree in Electrical Engineering from State University of Campinas (UNICAMP), Brazil, in 1986. He worked at CPqD (Brazilian PTT R&D Center) till 1996 designing analog and mixed signal circuits for telecom and automotive applications. From 1997 to the second half of 1998, he worked at Instituto Superior Técnico (IST), Lisbon, Portugal, under the guidance of Prof. Carlos Azeredo Leme on development of CMOS RF circuits. Since October 1998 he had worked for Motorola SPS. Now he is head of the Power Managment Group at Freescale.Cristiano Benevento received his B.S. degree in Electrical Engineering from Universidade Estadual de Campinas (Unicamp), Brazil, in 1997. He worked at Motorola Cellular Infrastructure Group until August 2000 as a Systems Engineer. He joined Motorola Semiconductor Product Sector in August 2000 as IC Designer for Power Management Group and is now at Freescale.  相似文献   
97.
The biomineralization capacity of the photosynthetic marine diatom Nitzschia frustulum was harnessed to fabricate Si-Ge oxide nanocomposite materials. Germanium was incorporated into the diatom cell by a two-stage cultivation process. In stage 1, the N. frustulum cell suspension was grown up to cell density of 3 x 10(6) cells/mL in 0.35 mM silicic acid within a bubble-column photobioreactor. In stage 2, when all of the soluble silicon was consumed, 0.10 mM Ge(OH)4 or a mixture of 0.020 mM Ge(OH)4 and 0.25 mM Si(OH)4 were added to Si-starved cells. The cells assimilated soluble germanium by a surge uptake mechanism. The cell mass was thermally annealed in air at 800 degrees C for 6 h to oxidize carbonaceous materials. The thermally annealed cell biomass was characterized by TEM-EDS, FT-IR, and XRD. These measurements confirmed the formation nanostructured Ge-Si oxides composed of CaSiO3 and Ca3GeO5.  相似文献   
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Efficiencies of three flame retardants for cellulose, phosphoric acid, diammonium phosphate, and THPOH ammonia finish, have been evaluated based on the heat release value and the rate of heat release of treated fabrics burning in air measured with the isoperibol calorimeter. The results were compared and correlated with those obtained previously with the bomb-calorimetric technique. Complete heat balances were obtained for the systems studied by correlation of the calorimetric data and the measurement of combustible gases evolved from the fabric burning in air. The rate of heat release was found to correlate with the flame propagation rate measured at a 45° angle. The results from the heat, rate, and combustible gas measurements were interpretable in terms of existing mechanisms of flame-retardant action.  相似文献   
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