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61.
The present study was an experimental test of efficacy of a brief education intervention for increasing HIV/AIDS knowledge among cocaine-dependent outpatients. Participants were randomly assigned to an HIV/AIDS education intervention (experimental condition) or a sham intervention (control condition). Control participants were subsequently crossed over to the HIV/AIDS education intervention. Experimental participants had higher scores on tests of HIV/AIDS knowledge after receiving the education intervention than did control participants. Further supporting the intervention's efficacy, control participant scores also increased once participants were crossed over and received the education intervention. Scores at follow-up were lower than at postintervention but remained higher than baseline scores. Results support the intervention's efficacy for increasing HIV/AIDS knowledge among cocaine-dependent outpatients. This intervention is brief, inexpensive, and easily implemented. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
62.
In this paper we discuss our study of the problems 12 software companies experienced in software development. In total we present qualitative data collected from 45 focus groups that involved over 200 software staff. We look at how different practitioner groups respond to software process improvement problems. We show our classification and analysis of this data using correspondence analysis. Correspondence analysis is a graphical data representation method new to software development research. The aim of the work we present is to develop a more holistic understanding of the problems practitioners are experiencing in their attempts to improve their software processes. Our main finding is that there is an association between a company's capability maturity and patterns of reported problems. Organizational problems are more associated with high maturity companies than with low maturity companies. Low maturity companies are closely linked to problems relating directly to projects such as documentation, timescales, tools and technology. Our findings also confirm differences in practitioner group problems. Senior managers cite problems with goals, culture and politics. Project managers are concerned with timescales, change management, budgets and estimates. Developers are experiencing problems with requirements, testing, documentation, communication, tools and technology. These associations are displayed graphically through correspondence analysis maps.  相似文献   
63.
A dynamic feedback controller design method is proposed for multiple input systems. The method uses a novel choice of sliding surface to effect asymptotic linearisation of nonlinear differential input output systems and a class of state space systems. The stability of the overall system, that is a canonical state space form with a dynamic feedback, is analysed with a generalised Lyapunov approach plus an asymptotic analysis in a neighbourhood of the origin. The nonlinear system does not have to be expressed in regular form as is the case in many other sliding mode control approaches. A type of zero dynamics, which are the dynamics of the control, are involved. The resulting dynamic feedback is shown to provide chatter free control if the system is minimum phase with respect to the zero dynamics. The theoretical results are applied to Gas Jet systems with two controls.  相似文献   
64.
The authors examined the validity of D. R. Lynam and T. A. Widiger's (2001) prototypes for personality disorders (PDs) derived from the facets of the 5-factor model (FFM) of personality in 2 clinical samples. In the 1st sample (N = 94), there was good agreement between the prototypes generated by experts and the profiles reported by patients. These FFM PD similarity scores also demonstrated good convergent and discriminant validity with results from a semistructured interview and a self-report measure of Axis II pathology. In the 2nd sample (N = 132), the FFM PD similarity scores demonstrated excellent longitudinal stability and good predictive validity with regard to consensus ratings of PD features. The implications of these findings are discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
65.
Antivirus software tests are important when selecting antivirus software. However, there are many different tests, and interpreting the results can be challenging. Additionally, the needs of the corporate customer and home user differ, and it is important to understand these differences in order to evaluate antivirus software tests critically.  相似文献   
66.
Stories capture the characteristics of the design space and audience that designers and engineers need to understand to build a complete and useful software experience. A story is a design communication tool that transcends the cultural divides of multidisciplinary teams and intertwines a technology with its user's goals. This article describes how stories are powerful tools in software design, defines the elements that make a compelling story, and presents the use of stories at IBM from the authors' experience. It also explores the benefits at each phase of the design process and how stories evolve throughout the design process.  相似文献   
67.
Simulation is a powerful tool for improving, evaluating and analyzing the performance of new and existing systems. Traffic simulators provide tools for studying transportation systems in smart cities as they describe the evolution of traffic to the highest level of detail. There are many types of traffic simulators that allow simulating traffic in modern cities. The most popular traffic simulation approach is the microscopic traffic simulation because of its ability to model traffic in a realistic manner. In many cities of Saudi Arabia, traffic management represents a major challenge as a result of expansion in traffic demands and increasing number of incidents. Unfortunately, employing simulation to provide effective traffic management for local scenarios in Saudi Arabia is limited to a number of commercial products in both public and private sectors. Commercial simulators are usually expensive, closed source and inflexible as they allow limited functionalities. In this project, we developed a local traffic simulator “KSUtraffic” for traffic modeling, planning and analysis with respect to different traffic control strategies and considerations. We modeled information specified by GIS and real traffic data. Furthermore, we designed experiments that manipulate simulation parameters and the underlying area. KSUTraffic visualizes traffic and provides statistical results on the simulated traffic which would help to improve traffic management and efficiency.  相似文献   
68.
With the advent of ‘big data’ there is an increased interest in using social media to describe city dynamics. This paper employs geo-located social media data to identify ‘digital neighborhoods’ – those areas in the city where social media is used more often. Starting with geo-located Twitter and Foursquare data for the New York City region in 2014, we applied spatial clustering techniques to detect significant groupings or ‘neighborhoods’ where social media use is high or low. The results show that beyond the business districts, digital neighborhoods occur in communities undergoing shifting socio-demographics. Neighborhoods that are not digitally oriented tend to have higher proportion of minorities and lower incomes, highlighting a social–economic divide in how social media is used in the city. Understanding the differences in these neighborhoods can help city planners interested in generating economic development proposals, civic engagement strategies, and urban design ideas that target these areas.  相似文献   
69.
We report preliminary experimental measurement of the twin-beam quantum state via optical homodyne tomography using a single local oscillator. The experiment is a realization of the recently reported ‘universal homodyne tomography’ technique. The results agree well with theoretical predictions and reveal the non-classical photon-number correlation between the signal and idler photons of the twin-beam state.  相似文献   
70.
Commercial aquaculture feeds rely heavily on fishmeal and fish oil, which can be expensive and ecologically unsustainable. To evaluate the efficacy of reduced fishmeal diets for outgrowth, a dietary study was conducted on the finfish cobia, Rachycentron canadum. NMR-based metabolomic techniques were used to assess the effect of decreasing dietary fishmeal on the health of the cobia. Filtered serum 1H NMR spectra analysed by principal components analysis (PCA) showed cobia fed reduced fishmeal diets were metabolically different than cobia on control diets. In particular, tyrosine and betaine increased in cobia fed reduced fishmeal diets while glucose decreased, suggesting that these cobia were not receiving the necessary nutritional components required for energy and growth. The formulated control diet contributed to enriched growth and significantly elevated lactate levels suggesting enhanced gut microflora metabolism in response to dietary components. The results show that NMR-based metabolomic analysis is a useful tool in aquaculture studies.  相似文献   
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