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171.
John Munro 《Civil Engineering and Environmental Systems》2013,30(1):37-41
Conventional linear programming requires the deterministic specification of all the relevant data but generally this is only known imprecisely. Several ways in which imprecision may be incorporated into the programs are discussed. These include proximate programming, inexact programming and fuzzy programming. A simple illustrative example concerned with water quality is reworked using some of the described techniques. Fuzzy programming is a particularly useful model which can handle imprecision with respect to all the parameters and can also incorporate multiple goals. 相似文献
172.
《Food Control》2017
The concept of Food Safety Margin (FSM) was introduced in microbiological risk analysis as an alternative approach to risk characterization within the informed-risk decision-making process. Its aim was to verify compliance with food safety objectives by assessing the effects of uncertainties. This paper describes the fundamentals and develop a new formulation of safety margins to verify compliance with food safety goals in relation to exposure to non-genotoxic chemical hazards. Both classical and probabilistic metrics were used to compare a given exposure to an estimated daily intake (EDI) with a given safety goal, the acceptable daily intake (ADI). The safety margins of these metrics were assessed in the exposure of peaches to organophosphorus pesticides. The pesticides considered were Azinphos-methyl, Chlorpyrifos, Diazinon, Dimethoate, Methamidophos, Parathion-methyl and Phosmet. The concentrations were obtained from the USDA pesticide database. The study period included the 11 years in which peaches were analysed from 1994 to 2014. The results show the importance of using the effect of uncertainty instead of mean values for risk characterization and that not only safety margins increased during this period but also that uncertainty was reduced. In general, large safety margins were observed in the period studied and few situations were found in which exposure was outside the safety limits. 相似文献
173.
中德在焊接人员培训体系与焊接企业认证体系的多年合作为中国焊接体系与国际接轨、获取国际焊接学会授权奠定了基础;CANB,ATBs获得国际授权后,根据国内的实际情况,不断调整培养模式,促进国际焊接培训体系在国内的推广实施,20年来累计为国内培养了25000多名国际资质焊接专业人员(不含ISO 9606焊工等)。CANBCC获得国际授权10年来累计认证企业近600家,提升了焊接企业核心竞争力,促进了焊接企业高质量发展。 相似文献
174.
工作流将业务过程分解为有序的步骤并分配人力资源加以执行.资源分配受访问控制约束及资源异常干扰,存在可满足性和鲁棒性问题.而其鲁棒性验证又依赖于其可满足性判定,目前通过求可满足性的一个解来完成.本文提出另一种途径,通过统计解的个数来完成判定.特别地,通过多项式计数归约为有求解器可用的#SAT问题,给出了互斥和绑定约束下的可满足性计数算法.实验表明,相对目前时间复杂度最低的可满足性求解算法,该可满足性计数算法显著提高了实际判定效率和适用规模. 相似文献
175.
探究复杂和不确定环境中决策行为的情景依赖的特征,在统一的分析框架中厘清“各派”情景规划中的步骤逻辑及其内在差异;最后结合我国当前的城市发展决策及城市规划的角色,探索情景规划的应用路径、意义与前景.文章认为,情景规划的价值在于为决策者提供了基于其自身情景依赖的理性决策的机制,促使决策者探索规划成立的前提和空间现象背后的真实制约条件.情景规划正面回应了我国精英决策带来必然性的价值渗透,有利于推进规划从“技术决策”到“政治决策”再向“科学决策”的转变.应用过程中需明确情景规划相同步骤不兼容的不同逻辑,以避免混淆情景规划的丰富内涵. 相似文献
176.
Probabilistic models are given for estimatingthe error content in a structure afte.r thre" application of a checking strategy with given efficiency. The use of these models to optimize the level of effort expended on error control is illustrated. The analysis is carried out using-a Bayesian-decisiorv-theory approach,-and an overall model for structural decision-making is described. The applicability of the approach is illustrated by an example which considers the overall checking efficiency in the building process, combined with some failure statistics and failure cost estimates. The application of the approach to specific structural members is also discussed in the paper. 相似文献
177.
Planning practice requires ongoing interaction between regulatory “facts” and deliberative “norms”. Played out in local and strategic developments, “norms” are the agreed values and positions developed by advancing deliberative engagement of residents; while “facts” are the more rigid statutory procedures through which planning decisions are typically made. However, conflict arises between residents' groups and local government decision-makers when deliberative norms, now a key tenet of strategic planning processes, struggle to gain traction in the factual spaces provided by statutory planning regulations. A contentious planning process in St Kilda, Melbourne, Australia (concerning the redevelopment of a car park into a commercial and public space) highlights the challenges to deliberative engagement in highly-regulatory planning systems. Drawing on this contested case, this paper examines how the broader formal and relatively fixed framework of regulatory-based decision-making fails to support participatory principles, undermining both the desired communicative ethos and enduring collaborative outcomes and norm development. Specifically, the paper problematises tensions between residents' growing expectations for greater transparency and participation in planning, arising from a growing regard for deliberation in strategic planning, and the hegemonic nature of statutory planning that preserves planning control within the formal domain of government and the private sector. 相似文献
178.
《Structure and Infrastructure Engineering》2013,9(9):1176-1210
In infrastructure management, multi-criteria decision-making (MCDM) has emerged as a decision support tool to integrate various technical information and stakeholder values. Different MCDM techniques and tools have been developed. This paper presents a comprehensive review on the application of MCDM literature in the field of infrastructure management. Approximately 300 published papers were identified that report MCDM applications in the field of infrastructure management during 1980–2012. The reviewed papers are classified into application to the type of infrastructure (e.g. bridges and pipes), and prevalent decision or intervention (e.g. repair and rehabilitate). In addition, the papers were also classified according to MCDM methods used in the analysis. The paper provides taxonomy of those articles and identifies trends and new developments in MCDM methods. The results suggest that there is a significant growth in MCDM applications in infrastructure management applications of MCDM over the last decade. It has also been noted that many decision support tools based on multiple MCDM methods have been successfully used for infrastructure management. 相似文献
179.
矿业经济,技术预测决策的系统研究 总被引:2,自引:0,他引:2
本文对矿业经济、技术预测决策的系统研究进行了整体设计,并运用某大型采选联合铜矿企业历年的生产数据,建立了有关的灰色预测决策模型。结果表明灰色系统理论在矿业系统的经济、技术研究中的应用是有效的。 相似文献
180.