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1.
The main cause of death and serious disability in bicycle accidents is traumatic brain injury (TBI). The aim of this population-based study was to assess the incidence and costs of bicycle-related TBI across various age groups, and in comparison to all bicycle-related injuries, to identify main risk groups for the development of preventive strategies.Data from the National Injury Surveillance System and National Medical Registration were used for all patients with bicycle-related injuries and TBI who visited a Dutch emergency department (ED) between 1998 and 2012. Demographics and national, weighted estimates of injury mechanism, injury severity and costs were analysed per age group. Direct healthcare costs and indirect costs were determined using the incidence-based Dutch Burden of Injury Model.Between 1998 and 2012, the incidence of ED treatments due to bicycle-related TBI strongly increased with 54%, to 43 per 100,000 persons in 2012. However, the incidence of all bicycle-related injuries remained stable, from 444 in 1998 to 456/100,000 in 2012. Incidence of hospital admission increased in both TBI (92%) and all injuries from cycling (71%). Highest increase in incidence of both ED treatments and hospital admissions was seen in adults aged 55+. The injury rate of TBI per kilometre travelled increased (44%) except in children, but decreased (−4%) for all injuries, showing a strong decrease in children (−36%) but an increase in men aged 25+, and women aged 15+. Total costs of bicycle-related TBI were €74.5 million annually. Although bicycle-related TBI accounted for 9% of the incidence of all ED treatments due to cycling, it accounted for 18% of the total costs due to all bicycle-related injuries (€410.7 million). Children and adolescents (aged 0–24) had highest incidence of ED treatments due to bicycle-related injuries. Men in the working population (aged 15–64) had highest indirect costs following injuries from cycling, including TBI. Older cyclists (aged 55+) were identified as main risk group for TBI, as they had highest ED attendance, injury rate, injury severity, admission to hospital or intensive care unit, and costs.Incidence of ED treatments due to cycling are high and often involve TBI, imposing a high burden on individuals and society. Older cyclists aged 55+ were identified as main risk group for TBI to be targeted in preventive strategies, due to their high risk for (serious) injuries and ever-increasing share of ED visits and hospital admissions. 相似文献
2.
This study proposes an analytical and flexible terrain risk assessment method for military surveillance applications for mobile assets. Considering the risk as the degree of possibility of insurgent presence, the assessment method offers an efficient evaluation of risk in the surrounding terrain for military combat operating posts or observation posts. The method is designed for unmanned aerial vehicles as the surveillance assets of choice to improve the effectiveness of their use. Starting with the area map and geographical data, the target terrain is first digitized for space representation. Then the data of nine geographical parameters are used to formulate five contributing risk factors. These factors are incorporated in an analytical framework to generate a composite map with risk scores that reveal the potential high-risk spots in the terrain. The proposed method is also applied to a real-life case study of COP Kahler in Afghanistan, which was a target for insurgent attacks in 2008. The results confirm that when evaluated with the developed method, the region that the insurgents used to approach COP Kahler has high concentration of high-risk cells. 相似文献
3.
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
4.
管道风险管理方法研究 总被引:6,自引:0,他引:6
按照管道风险管理的流程分别对管道风险评价、风险控制和决策支持、效能测试和响应进行了论述。针对目前国内管道行业的情况,提出了进行管道风险评价的有效方法及维护措施。着重介绍了国外管道风险可接受标准的情况,作为国内制定管道风险评价标准的参考。 相似文献
5.
Accidents in different complex sociotechnical systems are rarely compared using the same theoretical framework for risk management. We conducted a comparative analysis of two Canadian public health disasters involving drinking water distribution systems, the North Battleford Cryptosporidium parvum outbreak in April 2001 and the Walkerton E. coli outbreak in May 2000. Both accidents resulted from a complex interaction between all levels of a complex sociotechnical system. However, the low-level physical and individual factors differed in the two cases, whereas, the high-level governmental and regulatory factors tended to be the same. These findings may have implications for the design of public policies to minimize risk in complex sociotechnical systems. 相似文献
6.
陈留成 《石油化工安全环保技术》2006,22(4):48-51
对聚丙烯二装置丙烯球罐液位计不锈钢螺栓失效的原因进行了分析,结合锰铬不锈钢(200系列)的性能和国内市场上的现状,分析了锰铬不锈钢在化工生产中应用的风险,提出了应对方法。 相似文献
7.
Summary Two independent random samples of sizesN
1 andN
2 from multivariate normal populationsN
p
(θ1,∑1) andN
p
(θ2,∑2) are considered. Under the null hypothesisH
0: θ1=θ2, a single θ is generated from aN
p(μ, Σ) prior distribution, while underH
1: θ1≠θ2 two means are generated from the exchangeable priorN
p(μ,σ). In both cases Σ will be assumed to have a vague prior distribution. For a simple covariance structure, the Bayes factorB and minimum Bayes factor in favour of the null hypotheses is derived. The Bayes risk for each hypothesis is derived and a
strategy is discussed for using the Bayes factor and Bayes risks to test the hypothesis. 相似文献
8.
Hydrocarbon exploration risk evaluation through uncertainty and sensitivity analyses techniques 总被引:1,自引:0,他引:1
Paolo Ruffo Livia Bazzana Alberto Consonni Anna Corradi Andrea Saltelli Stefano Tarantola 《Reliability Engineering & System Safety》2006,91(10-11):1155-1162
The evaluation of the exploration risk in the oil industry is a fundamental component of the decision process related to the exploratory phase. In this paper the two basic components of the exploratory risk: trap geometry and trapped hydrocarbon quantities (fluid), are compounded in a single coherent uncertainty and sensitivity approach. The results clarify that the model geometry influences each Petroleum System Modeling step and that the geometric uncertainty is correlated with the fluid uncertainty. The geometric uncertainty evaluation makes use of geostatistical techniques that produce a number of possible realizations of the trap geometry, all compatible with available data. The evaluation of the fluid uncertainty, through a Monte Carlo methodology, allows us to compute the possible quantities of oil and gas, generated in a basin and migrated from the hydrocarbon source location to each single trap. The final result is the probability distribution of oil and gas for each trap in the basin, together with other useful indicators like: the hydrocarbon filling probability map, the closure probability map, the drainage area probability map, the spilling paths probabilities, the trap-filling scenarios. 相似文献
9.
This paper presents a coordinated reverse logistics (CRL) management system for the treatment of multi-source hazardous wastes in a given region, in this case, a specific high-technology manufacturing zone. A linear multi-objective analytical model is formulated that systematically minimizes both the total reverse logistics operating costs and corresponding risks. In addition to inter-organizational logistics operating factors, environmental concerns are considered and formulated as corresponding risk-related constraints. Using the proposed model, results of numerical studies indicate that when the aspect of risk-induced penalties is not considered, the operational costs of regional hazardous-waste management can be efficiently reduced by 58%, compared to the existing operational costs at the study site. In addition, it is also observed that the corresponding weight associated with the risk-induced objective function embedded in the proposed model seems to have a significant effect on the CRL costs. 相似文献
10.
A general unified model is developed to predict one-component critical two-phase pipe flow. An extension of the Henry [Henry, R.E., 1970. The Two-Phase Critical Discharge of Initially Saturated or Subcooled Liquid. Nucl. Sci. Eng. 41, 336-342.] and Henry and Fauske [Henry, R.E., Fauske, H.K., 1970. The two-Phase critical Flow of One-Component Mixtures in Nozzles; Orifices and Short Tubes, ASME J. Heat Transfer, May 1970.] models to incorporate the effects of wall friction and the location of flashing inception is proposed. Modelling of the two-phase flow is accomplished by describing the evolution of the flow between the location of flashing inception and the exit (critical) plane. The model approximates the nonequilibrium phase change process via thermodynamic equilibrium paths. Included are the relative effects of varying the location of flashing inception, pipe geometry, fluid properties and length to diameter ratio. The model predicts that a range of critical mass fluxes exist and is bound by a maximum and minimum value for a given thermodynamic state. This range is more pronounced at lower subcooled stagnation states and can be attributed to the variation in the location of flashing inception. The model is based on the experimental study of critical two-phase flow rates of saturated and subcooled water through long tubes given in Part I of this work. In that study, the location of flashing inception was accurately controlled and adjusted through the use of a new device. The data obtained revealed that for fixed stagnation conditions, the maximum critical mass fluxes occurred with flashing inception located near the pipe exit; while minimum critical mass fluxes occurred with the flashing front located further upstream. The results of the present study, as well as available data since 1970 are compared with the model predictions. These data cover a wide range of conditions and include test section L/D ratios from 25 to 302 and a temperature and pressure range of 110-280°C and 0.16-6.9 Mpa, respectively. The predicted maximum and minimum critical mass fluxes show an excellent agreement with the range observed in the experimental data. 相似文献