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51.
The reduction of semantic priming following letter search of the prime suggests that semantic activation can be blocked if attention is allocated to the letter level during word processing. Is this true even for the very fast-acting component of semantic activation? To test this, the authors explored semantic priming of lexical decision at stimulus onset asynchronies (SOAs) of either 200 or 1000 ms. Following semantic prime processing, priming occurred at both SOAs. In contrast, no priming occurred at the long SOA following letter-level processing. Of greatest interest, at the short SOA there was priming following the less demanding consonant/vowel task but not following the more attention-demanding letter search task. Hence, semantic activation can occur even when attention is directed to the letter level, provided there are sufficient resources to support this activation. The authors conclude that the default setting during word recognition is for fast-acting activation of the semantic system. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
52.
Removal of tetracycline and sulfonamide antibiotics from water by micelles pre-adsorbed on montmorillonite was studied. Micelles of benzyldimethylhexadecylammonium (BDMHDA) were used. Batch experiments demonstrated that the micelle-clay complexes (1% w/w) removed 96-99.9% of antibiotics from their water solutions containing from 5 to 50 mg/L of pharmaceuticals. Column filters (25 cm) made of a mixture of quartz sand and BDMHDA micelle-clay complex at 100:1 w/w ratio removed 94-99.9% of above pharmaceuticals from initial solutions containing 10mg/L and 89% of sulfamethizole from an initial solution containing 10 microg/L of this antibiotic. These filters were also very efficient in the removal of antibiotics in the presence of dissolved soil organic matter removing 89-99% of tetracycline and sulfamethizol from initial solutions containing 10 mg/L of antibiotic in the presence of 8 mg/L of humic acid, or 9 mg/L of fulvic acid. These data indicate that micelle-clay complexes are very efficient for water purification from tetracycline and sulfonamide antibiotics.  相似文献   
53.
Burnout is characterized by emotional exhaustion, physical fatigue, and cognitive weariness, resulting from prolonged exposure to work-related stress. The authors review the accumulated evidence suggesting that burnout and the related concept of vital exhaustion are associated with increased risk of cardiovascular disease and cardiovascular-related events. The authors present evidence supporting several potential mechanisms linking burnout with ill health, including the metabolic syndrome, dysregulation of the hypothalamic-pituitary-adrenal axis along with sympathetic nervous system activation, sleep disturbances, systemic inflammation, impaired immunity functions, blood coagulation and fibrinolysis, and poor health behaviors. The association of burnout and vital exhaustion with these disease mediators suggests that their impact on health may be more extensive than currently indicated. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
54.
Summary Analyzing distributed protocols in various models often involves a careful analysis of the set ofadmissible runs, for which the protocols should behave correctly. In particular, the admissible runs assumed by at-resilient protocol are runs which are fair for all but at mostt processors. In this paper we defineclosed sets of runs, and suggest a technique to prove impossibility results fort-resilient protocols, by restricting the corresponding sets of admissible runs to smaller sets, which are closed, as follows: For each protocolPR and for each initial configurationc, the set of admissible runs ofPR which start fromc defines a tree in a natural way: the root of the tree is the empty run, and each vertex in it denotes a finite prefix of an admissible run; a vertexu in the tree has a sonv iffv is also a prefix of an admissible run, which extendsu by one atomic step.The tree of admissible runs described above may contain infinite paths which are not admissible runs. A set of admissible runs isclosed if for every possible initial configurationc, each path in the tree of admissible runs starting fromc is also an admissible run. Closed sets of runs have the simple combinatorial structure of the set of paths of an infinite tree, which makes them easier to analyze. We introduce a unified method for constructing closed sets of admissible runs by using a model-independent construction of closedschedulers, and then mapping these schedulers to closed sets of runs. We use this construction to provide a unified proof of impossibility of consensus protocols. Ronit Lubitch received her B.Sc. degree in Mathematics and Computer Science from Tel Aviv University in 1989, and her Master degree in Computer Science from the Technion, in 1993. From 1992 she is working in Graffiti Software Industries, which expertise in the design and development of advanced photo realistic rendering, and animation software systems. Shlomo Moran received his B.Sc. and Ph.D. degrees in Mathematics from the Technion in 1975 and 1979 resp. In 1979–1981 he was at the University of Minnesota as a visiting research specialist. In 1981 he joined the Computer Science Department at the Technion, where he is now a full professor. In 1985–1986 he visited at IBM T.J. Watson Research Center. In 1992–1993 he visited at AT&T Bell Laboratories and in Centrum voor Wiskunde en Informatica, Amsterdam. His research interests include distributed computing, Combinatorics and Graph Theory, and Complexity Theory.A preliminary extended version of this paper appeared in the Proceedings of 6-th International Workshop on Distributed Algorithms, Haifa, November 1992This work was supported in part by the Technion V.P.R. fund. Part of this research was conducted while this author was visiting at AT&T Bell Labs at Murray Hill and at CWI, Amsterdam  相似文献   
55.
Gelatinized starch formulations including lipids and xanthan gum, typical of viscoelastic foodstuffs, were analyzed using a rotational viscometer (transient conditions) and an oscillatory rheometer. Ultra-rapid and slow freezing processing conditions, which can modify product stability, were also tested. Transient shear stress curves showed a typical overshoot and a structural breakdown; the Bird-Leider model satisfactorily fitted these curves. Model parameters were correlated with characteristic peak stress (αmax), peak time (tmax) and relative overshoot corresponding to the α vs time curve. Relationships between transient shear stress data and dynamic measurements (G', G*, δ) for viscoelastic ranges were found for the starch-based systems and were used to assign a physical meaning to Bird-Leider parameters. Viscoelastic starch systems were grouped in different zones of the correlation diagrams based on structure properties like rigidity, stability to the applied strain and fluid characteristics after breakdown.  相似文献   
56.
Disambiguation of heterophonic and homophonic homographs was investigated in Hebrew using semantic priming. Ambiguous primes were followed by unambiguous targets at 100 msec, 250 msec, and 750 msec stimulus onset asynchrony (SOA). Lexical decision for targets related to the dominant phonological alternatives of heterophonic homographs was facilitated at all SOAs. Targets related to subordinate alternatives were facilitated only at SOAs of 250 msec or longer. When the primes were homophonic homographs, semantic relationship facilitated lexical decision to targets at all SOAs regardless of the dominance of the meaning to which the targets were related. These data can be accounted for by assuming multiple lexical entries for heterophonic homographs, single lexical entries for homophonic homographs, and phonological mediation of accessing meanings. Language-specific factors probably account for the long-lasting activation of subordinate meanings. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
57.
Studies in psychology often have low power because of inadequate sample size. Thus, recent articles in the Journal of Consulting and Clinical Psychology have suggested making sample size determinations through readily available tables that are based on population normality. Questions have been raised on the use of these power tables because prevalent psychometric distributions, such as the discrete mass at zero with gap that occurs with 1st use or onset variables, are radically nonnormal. In addition to demonstrating the robustness of the independent samples t test with respect to Type I error, the major finding of this study shows that researchers may use these power tables without modification for this radically nonnormal distribution. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
58.
59.
This work addresses the ‘hard collision’ approach to the solution of planar, simple non-holonomic systems undergoing a one-point collision-with-friction problem, showing that (i) there are no coherent types of collision whereby forward sliding follows sticking, unless the initial relative tangential velocity of the colliding points vanishes; and (ii) the type of collision can be determined directly, given the collision angle of incidence \(\alpha\) and Coulomb’s coefficient of friction \(\mu\) between the colliding points. The classic hitting rod problem is used to illustrate the \(\alpha \)\(\mu\) collision-type dependence. Finally, the relation between collision with friction and tangential impact problems in multibody systems is briefly discussed.  相似文献   
60.
Background: Smartphones have reached levels of popularity and penetration where they are now suitable for use in population health interventions. A key feature of smartphones is push notification or in app messaging service, which can be used to alert users to messages or instructions pertaining to an installed app. Little evidence exists as to the persuasive power of these messages.

Method: We conducted a 24-week live user evaluation of push notifications used in a behavior-based mobile app for a meal replacement program to understand the role of push notifications in persuading users to engage with self-monitoring tasks.

Results: User perception of the prompts were verified through questionnaires, which in conjunction with the interaction logs show that users were tolerant of multiple daily prompts. The decline in compliance to the tasks set, however, shows that while the participants did not object to receiving prompts, they were less likely to respond to them as the study progressed.

Conclusions: Push notifications and user tasks are appropriate mechanisms to engage users with mobile technology in the short term.  相似文献   

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