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41.
Three experiments examined how norms characteristic of a "culture of honor" manifest themselves in the cognitions, emotions, behaviors, and physiological reactions of southern White males. Participants were University of Michigan students who grew up in the North or South. In 3 experiments, they were insulted by a confederate who bumped into the participant and called him an "asshole." Compared with northerners (who were relatively unaffected by the insult) southerners were more likely to think their masculine reputation was threatened, more upset (as shown by a rise in cortisol levels), more physiologically primed for aggression (as shown by a rise in testosterone levels), more cognitively primed for aggression, and more likely to engage in aggressive and dominant behavior. Findings highlight the insult–aggression cycle in cultures of honor, in which insults diminish a man's reputation and he tries to restore his status by aggressive or violent behavior. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
42.
This study addressed the issue of adjustment among Holocaust survivors by multidimensional assessment of subjective well-being (SWB). Participants were Israeli Holocaust survivors incidentally included in a life-span study (Group 1; n?=?466) or purposely approached for studying Holocaust survivors (Group 2; n?=?178). Comparison participants had immigrated to Israel before World War II, with their parents either undergoing (Group 3; n?=?270) or not undergoing the Holocaust (Group 4; n?=?388); other comparison participants had immigrated after the war with parents not undergoing the Holocaust (Group 5; n?=?166). Results showed that Group 1 scored lower than Group 2, mainly in positive affect. Group 1 scored lower than Group 4, and to a lesser extent also lower than Groups 3 and 5, mainly in aging-related themes of SWB. The study suggests that long-term effects of the Holocaust on the survivors' SWB are traceable but require a differential approach to the study groups and to the facets of SWB. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
43.
44.
We introduce a methodology whereby an arbitrary logic system L can be enriched with temporal features to create a new system T(L). The new system is constructed by combining L with a pure propositional temporal logic T (such as linear temporal logic with Since and Until) in a special way. We refer to this method as adding a temporal dimension to L or just temporalising L. We show that the logic system T(L) preserves several properties of the original temporal logic like soundness, completeness, decidability, conservativeness and separation over linear flows of time. We then focus on the temporalisation of first-order logic, and a comparison is make with other first-order approaches to the handling of time.  相似文献   
45.
Examined implicit leadership theory (preconceptions about the patterning of leadership variables) in 235 college students. Ss completed the Survey of Organizations questionnnaire on a fictitious "Plant X" about which they were given little information. Factor analysis, performed on the items purported to measure 4 leadership factors, resulted in the conceptualized factor structure. Since no information was given regarding supervisory behavior in Plant X, the factor structure was attributed to an implicit leadership theory. Factor analysis on subsamples indicated the factor structure could not be attributed to either experience in organizations or previous instruction in management. It is suggested that responses to questionnaires regarding organizational variables may be contaminated by implicit theory and that multitrait-multimethod procedures may be required to validate questionnaires. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
46.
We demonstrate how a single-celled organism could undertake associative learning. Although to date only one previous study has found experimental evidence for such learning, there is no reason in principle why it should not occur. We propose a gene regulatory network that is capable of associative learning between any pre-specified set of chemical signals, in a Hebbian manner, within a single cell. A mathematical model is developed, and simulations show a clear learned response. A preliminary design for implementing this model using plasmids within Escherichia coli is presented, along with an alternative approach, based on double-phosphorylated protein kinases.  相似文献   
47.
An analytical model is presented that describes the bending process following the absorption of a Gaussian laser pulse by the surface of a moderately thick metal plate. The model is based on the constitutive equations of thermoelastoplasticity and therefore fundamentally describes this optodynamic process. Assuming relatively short laser pulses, Green's function is used as an approximation for the real plate temperature. The plate is assumed to be made of elastic, linearly hardening material.  相似文献   
48.
Crack deflection in single-crystal brittle occurs when a crack, propagating on one cleavage plane, ‘chooses’, from energy considerations, to continue propagating on another cleavage plane. This phenomenon was identified during dynamic crack propagation experiments of thin, rectangular [0 0 1] single-crystal (SC) silicon specimens subjected to three-point bending (3PB). Specimens with long pre-cracks (hence propagating at a ‘low’ energy and velocity) cleave along the vertical (1 1 0) plane, while the same specimens but with short pre-cracks (and therefore with higher propagation energy and velocity) cleave along the inclined (1 1 1) plane. The same specimens with intermediate pre-crack length show that the crack first propagates on the (1 1 0) plane and then deflects to the (1 1 1) plane. We show that the deflection is due to variations of the material property that resists cracking, Γ, the dynamic cleavage energy, with velocity and crystallographic orientation. We propose selection criteria to explain the deflection: The crack will deflect to the plane with the lowest dynamic cleavage energy. We further suggest that crack deflection is the basic mechanism controlling the way the crack consumes energy while propagating and is the main cause of surface perturbations. The spatial temporal fracture energy along the (1 1 0) cleavage plane is evaluated.  相似文献   
49.

Purpose

The objective of this study was to develop and test the reliability and validity of a new scale designed for measuring safety climate among mobile remote workers, using utility/electrical workers as exemplar. The new scale employs perceived safety priority as the metric of safety climate and a multi-level framework, separating the measurement of organization- and group-level safety climate items into two sub-scales. The question of the emergence of shared perceptions among remote workers was also examined.

Method

For the initial survey development, several items were adopted from a generic safety climate scale and new industry-specific items were generated based on an extensive literature review, expert judgment, 15-day field observations, and 38 in-depth individual interviews with subject matter experts (i.e., utility industry electrical workers, trainers and supervisors of electrical workers). The items were revised after 45 cognitive interviews and a pre-test with 139 additional utility/electrical workers. The revised scale was subsequently implemented with a total of 2421 workers at two large US electric utility companies (1560 participants for the pilot company and 861 for the second company). Both exploratory (EFA) and confirmatory factor analyses (CFA) were adopted to finalize the items and to ensure construct validity. Reliability of the scale was tested based on Cronbach's α. Homogeneity tests examined whether utility/electrical workers’ safety climate perceptions were shared within the same supervisor group. This was followed by an analysis of the criterion-related validity, which linked the safety climate scores to self-reports of safety behavior and injury outcomes (i.e., recordable incidents, missing days due to work-related injuries, vehicle accidents, and near misses).

Results

Six dimensions (Safety pro-activity, General training, Trucks and equipment, Field orientation, Financial Investment, and Schedule flexibility) with 29 items were extracted from the EFA to measure the organization-level safety climate. Three dimensions (Supervisory care, Participation encouragement, and Safety straight talk) with 19 items were extracted to measure the group-level safety climate. Acceptable ranges of internal consistency statistics for the sub-scales were observed. Whether or not to aggregate these multi-dimensions of safety climate into a single higher-order construct (overall safety climate) was discussed. CFAs confirmed the construct validity of the developed safety climate scale for utility/electrical workers. Homogeneity tests showed that utility/electrical workers’ safety climate perceptions were shared within the same supervisor group. Both the organization- and group-level safety climate scores showed a statistically significant relationship with workers’ self-reported safety behaviors and injury outcomes.

Implications

A valid and reliable instrument to measure the essential elements of safety climate for utility/electrical workers in the remote working situation has been introduced. The scale can provide an in-depth understanding of safety climate based on its key dimensions and show where improvements can be made at both group and organization levels. As such, it may also offer a valuable starting point for future safety interventions.  相似文献   
50.
A compact model II fracture specimen was previously analyzed and employed to determine the mode II fracture toughness K IIc , of perspex. In employing this specimen for a more ductile material such as aluminium, it was observed that the load vs. crack sliding displacement record becomes nonlinear for small loads. Thus, concepts of linear elastic fracture mechanics cannot be employed. To this end, the specimen was calibrated for J-integral testing, so that J IIc mesurements can be performed.In this study, mode I and II tests are carried out on an aircraft aluminium alloy, AI 7075-T7351. First, standard K Ic tests are performed leading to a value of 27.9 15-1 which would be equivalent to a J Ic of 10.7 kN/m. Then standard J Ic tests are carried out on this material with specimen thicknesses, of 5, 7.5 and 9.9 mm, leading to an average J Ic value of 10.5 kN/m. Methods for J II testing are proposed; a series of specimens of six thicknesses between 5 and 16 mm are employed for testing. An average J IIc value was found to be 40.2 kN/m which yields a K IIc value of 54.1 15-2. Thus, K IIc is seen to be approximately twice that of K Ic for this material.  相似文献   
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