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91.
Classroom interactivity is a critical component of teaching and learning. This paper reports on the use of a classroom response system to enhance classroom interactivity in a systems analysis and design course. The success of the project was assessed using both quantitative and qualitative data. A pretest/posttest design was used to examine the effects of a classroom response system on interactivity. The results show that a classroom response system can significantly improve classroom interactivity. Qualitative data was also collected to identify the strengths and weaknesses of using a classroom response system to enhance classroom interaction. Based on the quantitative and qualitative results, suggestions and guidelines on using a classroom response system in the classroom settings are discussed. 相似文献
92.
Wah B.W. Huang T.S. Joshi A.K. Moldovan D. Aloimonos J. Bajcsy R.K. Ballard D. DeGroot D. DeJong K. Dyer C.R. Fahlman S.E. Grishman R. Hirschman L. Korf R.E. Levinson S.E. Miranker D.P. Morgan N.H. Nirenburg S. Poggio T. Riseman E.M. Stanfill C. Stolfo S.J. Tanimoto S.L. Weems C. 《Knowledge and Data Engineering, IEEE Transactions on》1993,5(1):138-154
The findings of a workshop, the goals of which were to identify applications, research problems, and designs of high performance computing and communications (HPCC) systems for supporting applications are discussed. In computer vision, the main scientific issues are machine learning, surface reconstruction, inverse optics and integration, model acquisition, and perception and action. In speech and natural language processing (SNLP), issues were identified statistical analysis in corpus-based speech and language understanding, search strategies for language analysis, auditory and vocal-tract modeling, integration of multiple levels of speech and language analyses, and connectionist systems. In AI, important issues that need immediate attention include the development of efficient machine learning and heuristic search methods that can adapt to different architectural configurations, and the design and construction of scalable and verifiable knowledge bases, active memories, and artificial neural networks 相似文献
93.
Yun Tu David Kingston Judy Kung Luba S. Kotlyar Bryan D. Sparks Keng H. Chung 《Petroleum Science and Technology》2006,24(3):327-338
The effectiveness of commercial oilsands separation processes relies on the water wettability of the solids. Consequently, the interaction between the mineral and organic matter types present in oilsands is of interest. In this work, we report results related to the adsorption of a pentane insoluble fraction from bitumen on kaolinite and illite, the major clay types present in oilsands. We determined adsorption from toluene solution by illite and kaolinite and use a combination of spectroscopic techniques to probe the organic coated clay surfaces to different depths. The results are compared with similar data for equivalent natural fractions from oilsands. 相似文献
94.
Huang Y.S. Chai Wah Wu 《Circuits and Systems II: Express Briefs, IEEE Transactions on》2005,52(4):181-184
We present some new global stability results of neural networks with delay and show that these results generalize recently published stability results. In particular, several different stability conditions in the literature which were proved using different Lyapunov functionals are generalized and unified by proving them using the same Lyapunov functional. We also show that under certain conditions, reversing the directions of the coupling between neurons preserves the global asymptotical stability of the neural network. 相似文献
95.
Synchronization in arrays of coupled nonlinear systems with delay and nonreciprocal time-varying coupling 总被引:1,自引:0,他引:1
Chai Wah Wu 《Circuits and Systems II: Express Briefs, IEEE Transactions on》2005,52(5):282-286
We study synchronization in an array of coupled nonlinear systems with delay and nonreciprocal time-varying coupling and present synchronization criteria which generalize previous synchronization results. We show that the array synchronizes when the nondelay coupling term is cooperative and large enough. Furthermore, we show that the synchronization criteria are related to several matrix quantities describing the coupling topology. These quantities can be considered as generalizations of the concept of algebraic connectivity to directed graphs. 相似文献
96.
It is pointed out that the tuning rules for under damped system and non‐minimum phase system that given by Haeri is incorrect. 相似文献
97.
A prototype transverse phase modulator employing the organic electrooptic MNA (2-methyl-4-nitroaniline) crystal is described. The design configurations and performance characteristics are presented. MNA was purchased as a fine greenish-yellow powder and was purified by multiple sublimations under low pressure. Purified MNA powder was subsequently saturated in acetone. To start growth, the beaker of filtered solution was placed in the dessicator with an equal volume of toluene on the bottom. The vapors of the solvent would fill the sealed vessel and get reabsorbed into the liquids. In the process, toluene molecules displaced the MNA ones, forcing them to precipitate out into crystalline form. Under controlled conditions of stable temperature and vapor exchange rate, large quality samples were obtained 相似文献
98.
A guillotine-type quick freezing device and a bio-hazard containment box have been designed, constructed, and used to prepare vitrifiedhydrated specimens of viruses in their native environment. Special design considerations include the preservation of the specimen in its natural state in vitrified ice, prevention of virus aerosols escape, and control of the potentially explosive air-coolant vapor mixtures. 相似文献
99.
Sexually mature males of Bactrocera papayae are strongly attracted to and consume methyl eugenol (ME). Upon consumption, ME is biotransformed to two phenylpropanoids, 2-allyl-4,5-dimethoxyphenol (DMP) and (E)-coniferyl alcohol (CF), that are transported in the hemolymph, sequestered and stored in the rectal glands, and subsequently released as sex and aggregation pheromones during courtship. To date, very little work on the ultrastructure and anatomy of the rectal gland has been done, and the accumulation of phenylpropanoids in the rectal glands of males has not been observed visually. Our objectives are to describe the anatomy and fine structures of the rectal glands of males and females and to observe the accumulation of autofluorescent compounds in the rectal glands of males. The rectal glands of males and females have four rectal papillae with each papilla attached to a rectal pad. The rectal pads protrude from the rectal gland as the only surfaces of the gland that are not surrounded by muscles. The rectal papillae of ME-fed males had oil droplets and autofluorescent compounds that were absent from those of ME-deprived males. The autofluorescent compounds accumulated in the rectal sac, which is an evagination that is not found in rectal glands of females. The accumulation of these compounds increased with time and reached maximum at a day post-ME feeding and decreased thereafter. This trend is similar to the accumulation pattern of phenylpropanoids, CF and DMP in the rectal gland. 相似文献
100.
采用200 kg级炼焦炉对熔融气化炉主要使用的2种块煤进行了不同时间的半焦裂解试验,比较了2种块煤成焦后的粒度分布和强度变化,发现B煤在炼焦炉内粉化严重,随结焦时间的延长其粒度降解度一直在升高,而A煤降解度在达到最大值后开始下降.对比了2种块煤生成半焦的矿相微观结构,A煤生成的半焦主要以镶嵌结构和各向同性结构为主,而B煤生成的半焦主要以类丝炭和各向同性结构为主;2种半焦均含有未成焦煤.通过分析熔融气化炉内取出的风口试样中不同粒度的含碳物质其矿相微观结构,认为在炉缸内6.3 mm的颗粒由2种块煤裂解成焦后的粉化现象所引起,且B煤的粉化是主要因素. 相似文献