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101.
矿产资源及其开采条件风险是矿业项目投资风险之根源.因此。分析了矿业项目投资风险时,合理估计矿产资源及其开采条件风险是至关重要的。针对矿产资源及其开采条件风险评价难以做到客观、全面、精确的问题,提出了矿产资源及其开采条件风险的模糊综合评判方法,建立了系统、全面的矿产资源及其开采条件风险评价指标体系,运用AHP法构建了风险评价的递阶层次结构,递阶层次分为3层:目标层、准则层(主因素层)和指标层(子因素层),并通过两两比较求出各指标的权重,进而建立了适用于矿产资源及其开采条件风险定量评价的多级模糊综合评判数学模型。  相似文献   
102.
The use of hydrogen as an energy carrier for road transport appears to be an optimal solution for the reduction of greenhouse gas emissions. Nevertheless, the development of this technology depends on the growth and diffusion of production, storage and refuelling infrastructures together with accurate risk analyses to appropriately design the safety and management systems used in these plants. Moreover, to improve safety standards, it is also important to focus attention on the estimation of hazards related to human factors, as this is one of the major causes leading to accidental events, especially in complex industrial technology. The paper reports a case study relevant to operator errors that occur during maintenance procedures on safety venting devices in refuelling station hydrogen storage systems performed using first- and second-generation Human Rate Assessment (HRA) techniques. HEART (Human Error Assessment and Reduction Technique) methodology, a first-generation HRA method, which was modified on the basis of the fuzzy set concept, was employed to evaluate the probability of erroneous actions. The obtained results have been compared with results obtained using CREAM (second-generation) methodology. The critical analyses of the obtained results have also allowed to provide procedural recommendations and suggestions regarding safety equipment and procedures which can be adopted to reduce the risk of accidents.  相似文献   
103.
Today, the utilizations of hydrogen storage systems (HSS), renewable generation units (PV and wind generation) and distributed energy units are increased in the intelligent parking lots (IPL) in order to charge the electric vehicles (EVs) with clean energy sources. In this work, the uncertainties of upstream grid price, the demand of IPL, wind speed, solar irradiation and temperature are modeled via scenario approach based on stochastic programing. Furthermore, the downside risk constraints method (DRCM) is applied to consider risk related to uncertainties to get risk-involved stochastic performance of hydrogen storage based intelligent parking lots of electric vehicles. The proposed risk-based formulation is modeled using mixed-integer linear programming (MIP) which is implemented under GAMS software and solved via CPLEX solver. Two cases namely risk-averse and risk-neutral strategies are studied and compared to show the effects of DRCM implementation. The obtained results demonstrate the expected performance cost (EPC) of IPL is slowly raised while risk-in-cost (RIC) is significantly reduced due to model of risk related to uncertainties.  相似文献   
104.
As hydrogen is a comparatively less safe fuel compared to conventional fuels such as gasoline and diesel, major accidents such as explosions and fires at hydrogen refuelling stations close to residential areas may lead to catastrophic consequences. It is difficult for a traditional quantitative risk analysis (QRA) method to efficiently assess human safety in a large region that includes not only the hydrogen refuelling station but also nearby commercial and residential areas. Therefore, a grid-based risk mapping method has been developed to enable efficient and detailed risk screening of such large areas. The target area is divided into a number of grids of an appropriate size, and a risk analysis is conducted for each grid. A total risk map can be depicted based on the risk evaluations of all grids, and a detailed risk assessment can then be applied to the most hazardous grids. Meanwhile, in order to consider multiple consequences and the complex interrelationships between risk factors, a Bayesian network (BN) model is implemented for the proposed method. At the same time, to reduce uncertainties caused by a shortage of data, three kinds of data—practical information, computational simulations and subjective judgements—are involved in the quantification of the proposed BN. The results from the case study show that the proposed method is capable of effectively conducting risk screenings for large and complex situations.  相似文献   
105.
Monitoring programs are preferably risk-based, which allows focusing on the most relevant human health risks. In this study, a risk matrix was used to identify those chemical hazards that have the highest human health risk for the following spices and herbs: paprika/chilli powder, black pepper, nutmeg, basil, thyme, and parsley. Both the probability of occurrence and the severity of the hazard were assessed for 36 chemical compounds and classified into low, medium, high, and severe. Probability of occurrence was evaluated based on available monitoring data and RASFF notifications as well as possibilities for economic adulteration. Severity was assessed based on available toxicological reference values and classification of carcinogenicity. The results demonstrated that the mycotoxins aflatoxins and ochratoxin A, the pesticides chlorpyrifos and triazophos, and the dye Sudan I posed the highest human health risk for spices and herbs. These compounds should, therefore, have an increased monitoring frequency in these products.  相似文献   
106.
Risk allocation decisions are of critical importance in project management. The present study proposes an explanation for how risk allocation in a contract motivates a contractor to cooperate with a project owner. Theories of risk allocation and trust were used to motivate the research. Using a survey methodology, we collected data concerning 124 construction projects in China. We found that risk allocation influenced the contractor’s role behavior through the contractor’s feeling of being trusted but not the contractor’s trust in the owner. Feeling of being trusted partially mediated the effect of risk allocation on the contractor’s in-role (i.e., contractual) behavior and fully mediated the effect on extra-role behavior. The study introduces a social and psychological view of the impacts of risk allocation to the project and engineering management literature. We contribute to theory by arguing and demonstrating the mediating effect of trust on the relationship between risk allocation and contractor behavior. From a practical standpoint, we conclude that contractual risk allocation has a significant impact on building a trusting relationship between owners and contractors and that contractors who feel trusted perform both contractually mandated actions and actions external to the contract more diligently, resulting in the likelihood of improved outcomes for both parties.  相似文献   
107.
李春  依岩 《核动力工程》2013,34(4):185-188
基于美国核管理委员会(NRC)推行的在核电厂运用的概率安全评价(PRA)技术,介绍PRA质量的含义、NRC在应用PRA过程中提出的分阶段提高PRA质量的方法以及相应的管理导则。结合国内现状,给出提高PRA质量的可接受方法。  相似文献   
108.
叶常青 《辐射防护》1991,11(6):415-425,439
本文介绍了ICRP1990年建议书附件C的主要内容,着重阐述危险的概念,描述辐射照射引起的各种潜在危险的量,一次和长期照射条件下不同年龄时危险的增量及文中用多属性方法来选择工作人员或公众个体的剂量限值。  相似文献   
109.
Food technologies provide numerous benefits to society and are extensively vetted for safety. However, many technological innovations still face high levels of skepticism from consumers. To promote development and use of food technologies, it is critical to understand the psychological and neurobiological processes associated with consumer acceptability concerns. The current study uses a neuroscience-based approach to understand consumer attitudes and perceptions of risk associated with food technologies and investigate how such attitudes impact consumer’s processing of information related to food technologies. We used functional magnetic resonance imaging (fMRI) to measure brain activation while participants processed infographics related to food technology topics. For technology topics perceived as riskier (antibiotics and hormones), activation was higher in areas of the lateral prefrontal cortex that are associated with decisional uncertainty. In contrast, technology topics that were viewed more favorably (sustainability and animal welfare) tended to activate the ventromedial prefrontal cortex, a region that processes positive affect and subjective value. Moreover, for information about hormones, the lateral PFC activation was associated with individual differences in resistance to change in risk perception. These results reveal how attitudes and risk perception relate to how the brain processes information about food technologies and how people respond to information about such technologies.  相似文献   
110.
Risk perceptions and technology innovativeness are the two primary factors related to the adoption of mobile technologies. The current study examines the role of technology innovativeness and risk perceptions on smartphone use and dependence in an Asian context. A total of 9086 participants were recruited through online surveys from ten Asian countries. Ordinary least squares regression analyses revealed the effects of technology innovativeness, information security, privacy concern, and their interactions on smartphone use and dependence. Moreover, based on users’ smartphone usage patterns and perceptions, this paper identified four homogeneous groups using cluster analysis. Results shows that Asian smartphone users can be segmented into four groups: innovators, conservatives, moderators, and laggards. The four clusters show significant differences in demographic features. Theoretical and practical implications are discussed based on these findings.  相似文献   
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