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991.
The effects of adrenergic and corticosteroid hormonal systems on emotional memory were measured in 64 young men. Placebo, propranolol (40 or 80 mg; beta blocker), or metyiapone (corticosteroid synthesis inhibitor) was administered before the viewing of a story composed of emotional and neutral segments. Short- and long-term declarative memory for the story was assessed. Propranolol 40 mg had no effects on declarative memory. Propranolol 80 mg impaired short- and long-term declarative memory for emotionally arousing material. Metyrapone did not impair short-term declarative memory but impaired long-term declarative memory for emotionally arousing and neutral material. Results demonstrate that adrenergic and corticosteroid hormonal systems differentially affect declarative memory for emotionally arousing and neutral material, and suggest that interactions between adrenal hormonal systems modulate emotionally arousing declarative memory in humans. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
992.
The use of non-determinism in logic-based languages is motivated using pragmatic and theoretical considerations. Non-deterministic database queries and updates occur naturally, and there exist non-deterministic implementations of various languages. It is shown that non-determinism resolves some difficulties concerning the expressive power of deterministic languages: there are non-deterministic languages expressing low complexity classes of queries/updates, whereas no such deterministic languages are known. Various mechanisms yielding non-determinism are reviewed. The focus is on two closely related families of non-deterministic languages. The first consists of extensions of Datalog with negations in bodies and/or heads of rules, with non-deterministic fixpoint semantics. The second consists of non-deterministic extensions of first-order logic and fixpoint logics, using thewitness operator. The expressive power of the languages is characterized. In particular, languages expressing exactly the (deterministic and non-deterministic) queries/updates computable in polynomial time are exhibited, whereas it is conjectured that no analogous deterministic language exists. The connection between non-deterministic languages and determinism is also explored. Several problems of practical interest are examined, such as checking (statically or dynamically) if a given program is deterministic, detecting coincidence of deterministic and non-deterministic semantics, and verifying termination for non-deterministic programs.Work supported by the Projet de Recherche Coordonnée BD3.Work supported in part by the National Science Foundation under grants IRI-8816078 and INT-8817874. The work was done in part while the author was visiting INRIA.  相似文献   
993.
994.
Long-term calorie restriction (LCR) is widely known to increase the survival rate of laboratory rodents and appears to retard the aging and senescence process. The present study was undertaken in Fischer-344 male rats maintained onad libitum (AL) or LCR (40% less food intake than AL starting at 6 weeks of age). Age-associated changes in the proliferative response of lymphoid cells to mitogenic stimuli were studied in relation to alterations in the fatty acid composition of adherent and nonadherent-enriched subpopulations of spleen cells. Increases in spleen cell long-chain highly unsaturated fatty acids (20∶4, 22∶4 and 22∶5) were accompanied by decreases in linoleic acid (18∶2) in aging AL-fed rats. However, LCR stabilized levels of 18∶2 and prevented the rise in highly unsaturated fatty acids. In addition, LCR markedly modulated the fatty acid profiles of thymocytes and bone marrow cells. A 70% decline in concanavalin A (Con A) stimulated [3H]thymidine uptake of spleen cells from AL animals was normalized by LCR. Splenic reduced glutathione (GSH), a potential modulator of the mitogenic response, was unaffected by age and nutritional regimen. Thus, normalization of lymphoid cell fatty acid composition by LCR parallels the preservation of mitogenic responsiveness to Con A.  相似文献   
995.
The objectives of this study were: 1) to determine if a correlation exists between rumen odd and branched-chain fatty acids (OBCFA, i.e., C(15:0), iso C(15:0), anteiso C(15:0), C(17:0), iso C(17:0), anteiso C(17:0), and C(17:1)), uracil, and purine bases (PB), 2) to evaluate the potential of milk OBCFA secretion to predict duodenal flow of microbial protein in lactating cows, 3) to evaluate the accuracy of the latter prediction equations using an independent data set, and 4) to determine whether these predictions were more accurate than predictions based on dry matter intake (DMI) and dietary characteristics. In the first experiment, 4 lactating dairy cows arranged in a 4 x 4 Latin square were offered diets based on grass silages of different botanical composition and a standard concentrate. The relationship between rumen pool size of OBCFA and microbial matter was investigated. Rumen pool size of microbial matter (g), determined 4, 12, and 17 h after feeding, using uracil and PB as microbial markers, was closely related to OBCFA (g) [r(2) = 0.716, root mean square error (RMSE) = 4.45]. To correct for differences in marker concentrations among strains of rumen microbes, C(17:0) was included in the regression equations, resulting in an increased predictive power (r(2) = 0.780, RMSE = 3.92). The relationship between microbial flow to the duodenum and milk OBCFA yield was evaluated in a second experiment with lactating dairy cows offered diets based on grass silage and concentrates differing in starch source. Similar to observations in the rumen, milk OBCFA yield was closely related to microbial flow to the duodenum (RMSE = 4.28), but predictive power of equations did not increase when straight-chain C(17)-fatty acids were included in the regression equations (RMSE = 4.92). Evaluation of the current prediction equations with 3 independent datasets resulted in a root mean square prediction error of 20.5 and 13.4% of the observed mean for equations based on milk secretion of total OBCFA and straight-chain C(17)-fatty acids, respectively. Comparison of the accuracy of the latter equations with 2 previously published equations based on DMI and dietary characteristics suggest the former to be more accurate. This first evaluation suggests that milk OBCFA could be used as a marker for duodenal flow of microbial matter, especially when accurate measurements of DMI are not available.  相似文献   
996.
Aperture synthesis allows one to measure visibilities at very high resolutions by coupling telescopes of reasonable diameters. We consider the case where visibility amplitudes and phase are measured separately. It leads to an estimation problem where the noise model yields a nonconvex data-likelihood criterion. We show how to optimally approximate the noise model while keeping the criterion convex. This approximation has been validated both on simulations and on experimental data.  相似文献   
997.
Near-field photochemical imaging of noble metal nanostructures   总被引:1,自引:0,他引:1  
The sub-diffraction imaging of the optical near-field in nanostructures, based on a photochemical technique, is reported. A photosensitive azobenzene-dye polymer is spin coated onto lithographic structures and is subsequently irradiated with laser light. Photoinduced mass transport creates topographic modifications at the polymer film surface that are then measured with atomic force microscopy (AFM). The AFM images correlate with rigorous theoretical calculations of the near-field intensities for a range of different nanostructures and illumination polarizations. This approach is a first step toward additional methods for resolving confined optical near fields, which can augment scanning probe methodologies for high spatial resolution of optical near fields.  相似文献   
998.
Efficient shape matching using shape contexts   总被引:2,自引:0,他引:2  
We demonstrate that shape contexts can be used to quickly prune a search for similar shapes. We present two algorithms for rapid shape retrieval: representative shape contexts, performing comparisons based on a small number of shape contexts, and shapemes, using vector quantization in the space of shape contexts to obtain prototypical shape pieces.  相似文献   
999.
1000.
This paper presents the results of resistive-open defect insertion in different locations of Infineon 0.13 m embedded-SRAM with the main purpose of verifying the presence of dynamic faults. This study is based on the injection of resistive defects as their presence in VDSM technologies is more and more frequent. Electrical simulations have been performed to evaluate the effects of those defects in terms of detected functional faults. Read destructive, deceptive read destructive and dynamic read destructive faults have been reproduced and accurately characterized. The dependence of the fault detection has been put in relation with memory operating conditions, resistance value and clock cycle, and the importance of at speed testing for dynamic fault models has been pointed out. Finally resistive Address Decoder Open Faults (ADOF) have been simulated and the conditions that maximize the fault detection have been discussed as well as the resulting implications for memory test.This work has been partially funded by the French government under the framework of the MEDEA + A503 ASSOCIATE European program.A paper based on this work was presented at the Eighth IEEE European Test Workshop, Maastricht, The Netherlands, May 2003.Simone Borri received the M.Sc. Degree (summa cum laude) in Electronics Engineering from the University of Pisa (Italy) in 1995. In 1997 he joined STMicroelectronics as a digital designer in the DSP development group of S.S.D. (formerly Parthus, now Ceva), Dublin, Ireland. From 1998 to 2000 he was with ST Microelectronics, Milan, Italy as ASIC DSP designer in the Car Communication business unit. Since 2000 he is with Infineon Technologies, Sophia-Antipolis, France as Staff design engineer in the embedded-SRAM design group. He has recently joined the Secure Mobile System Business Unit. His current interests include BIST, DFT techniques and SoC verification. Simone is an IEEE member since 1995.Magali Hage-Hassan was born near Lyon (France) in 1979. She received a Master of Science degree of Microelectronics and Automatics from the Institute of Engineering Sciences of Montpellier in 2003. She is currently working for Infineon in the memory library department in Sophia-Antipolis. She participated to the European research project MEDEA associate. Hage-Hassans interest include memory test.Luigi Dilillo was born in Barletta (Italy) in 1974. At this moment he is doing his last year of Ph.D. in the Microelectronics Department of the Laboratory of Informatics, Robotics and Microelectronics of Montpellier (LIRMM) in France. He received his degree in Electrical Engineering in 2001, at Politecnico di Torino (Italy). His researches include MEMS and digital circuits. At this moment he is working on delay-fault testing, and memory testing.Patrick Girard is presently Researcher at CNRS (French National Center for Scientific Research), and works in the Microelectronics Department of the LIRMM (Laboratory of Informatics, Robotics and Microelectronics of Montpellier—France). His research interests include the various aspects of digital testing, with special emphasis on DfT, logic BIST, delay fault testing and diagnosis, low power testing and memory testing. He has authored and co-authored 1 book and more than 100 papers on these fields. He has managed several European research projects and industrial research contracts. He is Editor-in-Chief of JOLPE—Journal of Low Power Electronics, and Associate Editor of JEC—Journal of Embedded Computing. He will serve as Program vice-Chair for the International Conference on Embedded And Ubiquitous Computing in 2005 and as Program Chair for the IEEE International Workshop on Electronic Design, Test & Applications in 2006. He is also topic chair of two European conferences (DATE and ETS) and is member of the program committee of several other international conferences. Patrick GIRARD obtained the Ph.D. degree in microelectronics from the University of Montpellier in 1992 and the Habilitation à Diriger des Recherches degree from the University of Montpellier in 2003.Serge Pravossoudovitch was born in 1957. He is currently professor in the electrical and computer engineering department of the University of Montpellier and his research activities are performed at LIRMM (Laboratoire dInformatique, de Robotique et de Microélectronique de Montpellier). He got the Ph.D. degree in electrical engineering in 1983 for his work on symbolic layout for IC design. Since 1984, he is working in the testing domain. He obtained the doctorat détat degree in 1987 for his work on switch level automatic test pattern generation. He is presently interested in memory testing, delay fault testing, design for testability and power consumption optimization. He has authored and co-authored numerous papers on these fields, and has supervised several Ph.D. dissertations. He has also participated to several European projects (Microelectronic regulation, Esprit, Medea).Arnaud Virazel was born in Montpellier (France) in 1974. He is presently assistant professor at the university of Montpellier, and works with the LIRMM (Laboratoire dInformatique, de Robotique et de Microélectronique de Montpellier). He received the B.Sc. (1995) and the M.Sc. (1997) degrees in Electrical Engineering and the Ph.D. (2001) degree in Microelectronics, all from the University of Montpellier/LIRMM. A. Virazels interests include delay testing, memory testing and power optimization during test.  相似文献   
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