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11.
This paper details a new approach for learning a discriminative model of object classes, incorporating texture, layout, and context information efficiently. The learned model is used for automatic visual understanding and semantic segmentation of photographs. Our discriminative model exploits texture-layout filters, novel features based on textons, which jointly model patterns of texture and their spatial layout. Unary classification and feature selection is achieved using shared boosting to give an efficient classifier which can be applied to a large number of classes. Accurate image segmentation is achieved by incorporating the unary classifier in a conditional random field, which (i) captures the spatial interactions between class labels of neighboring pixels, and (ii) improves the segmentation of specific object instances. Efficient training of the model on large datasets is achieved by exploiting both random feature selection and piecewise training methods. High classification and segmentation accuracy is demonstrated on four varied databases: (i) the MSRC 21-class database containing photographs of real objects viewed under general lighting conditions, poses and viewpoints, (ii) the 7-class Corel subset and (iii) the 7-class Sowerby database used in He et al. (Proceeding of IEEE Conference on Computer Vision and Pattern Recognition, vol. 2, pp. 695–702, June 2004), and (iv) a set of video sequences of television shows. The proposed algorithm gives competitive and visually pleasing results for objects that are highly textured (grass, trees, etc.), highly structured (cars, faces, bicycles, airplanes, etc.), and even articulated (body, cow, etc.). J. Shotton is now working at Toshiba Corporate Research & Development Center, Kawasaki, Japan.  相似文献   
12.
On the basis of prior work integrating attachment theory and terror management theory, the authors propose a model of a tripartite security system consisting of dynamically interrelated attachment, self-esteem, and worldview processes. Four studies are presented that, combined with existing evidence, support the prediction derived from the model that threats to one component of the security system result in compensatory defensive activation of other components. Further, the authors predicted and found that individual differences in attachment style moderate the defenses. In Studies 1 and 2, attachment threats motivated worldview defense among anxiously attached participants and motivated self-enhancement (especially among avoidant participants), effects similar to those caused by mortality salience. In Studies 3 and 4, a worldview threat and a self-esteem threat caused attachment-related proximity seeking among fearful participants and avoidance of proximity among dismissing participants. The authors' model provides an overarching framework within which to study attachment, self-esteem, and worldviews. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
13.
Components of the therapeutic process have been shown to be moderately strong predictors of change in patients' global interpersonal functioning during therapy. The authors sought to extend this research by examining how the therapeutic process in time-limited dynamic psychotherapy related to change in patients' perceptions of a specific relationship as rated by the Structural Analysis of Social Behavior. Results showed that ratings of therapist warmth at Session 3 predicted increased warmth and decreased hostility in patient behavior at posttreatment. Therapist warmth at Session 16 was predictive of a decrease in submissive behavior by patients toward their significant other. The importance of the association between the therapeutic process and patients' important interpersonal relationships is discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
14.
The impact of benign breast biopsy (BBB) on distress and perceptions of risk for breast cancer (BC) was examined. Interviews were conducted with 100 women shortly after notification of biopsy results and 4 and 8 months post-BBB. Compared with matched healthy comparison (HC) women without BBB, the BBB group evidenced greater BC-specific distress at baseline. BC-specific distress declined after BBB, remaining elevated relative to the HC group at the 8-month follow-up. Dispositional (optimism, informational coping style), demographic (education), clinical (family history of BC), and cognitive (BC risk perception) variables were associated with baseline levels of BC-specific distress or persistence of distress. Results support the monitoring process model (S. M. Miller, 1995) and the cognitive social health information processing model (S. M. Miller, Y. Shoda, & K. Hurley, 1996). (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
15.
Atopic eczema (AE) is an inflammatory skin disorder affecting approximately 20% of children worldwide and early onset can lead to asthma and allergies. Currently, the mechanisms of the disease are not fully understood. Metabolomics, the analysis of small molecules in the skin produced by the host and microbes, opens a window to observe the mechanisms of the disease which then may lead to new drug targets for AE treatment. Here, we review the latest advances in AE metabolomics, highlighting both the lipid and non-lipid molecules, along with reviewing the metabolites currently known to reside in the skin.  相似文献   
16.
AIM: Mild heat stress can improve mitochondrial respiratory capacity in skeletal muscle. However, long-term heat interventions are scarce, and the effects of heat therapy need to be understood in the context of the adaptations which follow the more complex combination of stimuli from exercise training. The purpose of this work was to compare the effects of 6 weeks of localized heat therapy on human skeletal muscle mitochondria to single-leg interval training. METHODS: Thirty-five subjects were assigned to receive sham therapy, short-wave diathermy heat therapy, or single-leg interval exercise training, localized to the quadriceps muscles of the right leg. All interventions took place 3 times per week. Muscle biopsies were performed at baseline, and after 3 and 6 weeks of intervention. Mitochondrial respiratory capacity was assessed on permeabilized muscle fibers via high-resolution respirometry. RESULTS: The primary finding of this work was that heat therapy and exercise training significantly improved mitochondrial respiratory capacity by 24.8 ± 6.2% and 27.9 ± 8.7%, respectively (p < 0.05). Fatty acid oxidation and citrate synthase activity were also increased following exercise training by 29.5 ± 6.8% and 19.0 ± 7.4%, respectively (p < 0.05). However, contrary to our hypothesis, heat therapy did not increase fatty acid oxidation or citrate synthase activity. CONCLUSION: Six weeks of muscle-localized heat therapy significantly improves mitochondrial respiratory capacity, comparable to exercise training. However, unlike exercise, heat does not improve fatty acid oxidation capacity.  相似文献   
17.
Accurate measurement of cognitive strategies is important in diverse areas of psychological research. Strategy self-reports are a common measure, but C. Thevenot, M. Fanget, and M. Fayol (2007) proposed a more objective method to distinguish different strategies in the context of mental arithmetic. In their operand recognition paradigm, speed of recognition memory for problem operands after solving a problem indexes strategy (e.g., direct memory retrieval vs. a procedural strategy). Here, in 2 experiments, operand recognition time was the same following simple addition or multiplication, but, consistent with a wide variety of previous research, strategy reports indicated much greater use of procedures (e.g., counting) for addition than multiplication. Operation, problem size (e.g., 2 + 3 vs. 8 + 9), and operand format (digits vs. words) had interactive effects on reported procedure use that were not reflected in recognition performance. Regression analyses suggested that recognition time was influenced at least as much by the relative difficulty of the preceding problem as by the strategy used. The findings indicate that the operand recognition paradigm is not a reliable substitute for strategy reports and highlight the potential impact of difficulty-related carryover effects in sequential cognitive tasks. (PsycINFO Database Record (c) 2011 APA, all rights reserved)  相似文献   
18.
With the publication of Zür experimentalen ?sthetik (1871) and Vorschule der ?sthetik (1876), Fechner laid the foundations for a new field termed experimental aesthetics, and provided three methods for empirical research. Of these, the method of choice has dominated subsequent research. It is argued that this method, in combination with a narrow, post-Baumgarten definition of aesthetics as pertaining mainly to the experience of art, has not served aesthetics well. In so doing it has overlooked the vast corpus of everyday objects for which people engage in aesthetic choice. Termed mundane aesthetics, this represents the low end, design, as distinct from the high end, art. The aesthetics of the mundane represents everyday reality, far removed from the rarefied pursuit of art. A study is reported into that most mundane and ubiquitous activity, selecting a paint color for the home. It eschews the laboratory and, instead, uses a retrospective method supported by qualitative data analysis (NVivo). The results indicate that aesthetic choice involves processes that are far from uniform, far from instantaneous (cf. laboratory studies), and that employ both internal and external aids reflecting cognitive, emotional, and social considerations. Selecting a wall color emerges as a surprisingly sophisticated process and, on the basis of the present study, one that women appear better equipped to perform than men. A parallel is drawn with the domain of decision research, particularly naturalistic decision-making. Mundane aesthetics involves a decision process, and not simply an affective choice. (PsycINFO Database Record (c) 2011 APA, all rights reserved)  相似文献   
19.
Single-crystal diffuse scattering was collected on the Wombat high-intensity powder diffractometer at the OPAL reactor at the Bragg Institute. The difficulty in measuring diffuse scattering comes from its relatively low intensity compared to the Bragg peaks, a factor of 10310^{3} to 10410^{4} smaller. Wombat allows collection of diffuse scattering due to its high intensity and large two-dimensional detector. Diffuse scattering data from yttria-stabilized cubic zirconia (YCSZ, Y2O3hbox{Y}_2hbox{O}_3 stabilized ZrO2hbox{ZrO}_2) and PbZn1/3Nb2/3O3hbox{PbZn}_{1/3}hbox{Nb}_{2/3}hbox{O}_3 (PZN) were successfully collected, the latter at a range of temperatures. The data were processed, normalized, and background subtracted to reconstruct flat reciprocal space sections with a minimum of artifacts. The strategies used to tackle the collection of neutron diffuse scattering and the way in which they are implemented will be discussed. The results show that the neutron powder diffractometer with a continuous detector is capable of collecting high-quality diffuse scattering data.  相似文献   
20.
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