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51.
A. Arbona A. Artigues C. Bona-Casas J. Massó B. Miñano A. Rigo M. Trias C. Bona 《Computer Physics Communications》2013
Simflowny is a software platform which aims to formalize the main elements of a simulation flow. It allows users to manage (i) formal representations of physical models based on Initial Value Problems (hyperbolic, parabolic and mixed-type partial differential equations), (ii) simulation problems based on such models, and (iii) discretization schemes to translate the problem to a finite mesh. Additionally, Simflowny generates automatically code for general-purpose simulation frameworks. This paper first presents an introductory example of such problems. Then, formal representations are explained. Afterwards, it summarizes the platform’s architecture. Finally, validation results are provided. 相似文献
52.
本文从实用性的角度出发,对性能化设计步骤做了重新整理,归纳。以方便大家进一步理解抗震性能化设计,增强实际设计过程的可操作性。 相似文献
53.
《Journal of Nuclear Science and Technology》2013,50(1):5-10
Three versions of Japanese Evaluated Nuclear Data Library (JENDL) are briefly explained. The first version, JENDL-1, was made aiming mainly at application to fast reactors. The second version, JENDL-2, was built as a bigger general purpose evaluated nuclear data library. It stores nuclear data for 181 nuclides. It has, however, some drawbacks particularly for fusion neutronics calculation. To remove these drawbacks of JENDL-2 and further extend its applicability, the third version, JENDL-3, has now been made. JENDL-3 includes photon-production data for some nuclides, in addition to the data contained in JENDL-2. 相似文献
54.
工程项目二次创效,是指在保证满足工程质量、工期等合同约定的前提下,通过加强对工程项目施工过程有组织、有系统的进行预测、计划、控制、核算、分析、考核等科学管理活动,以达到强化经营管理、降低工程成本、实现目标利润、创造良好经济效益之目的。 相似文献
55.
Special purpose machine tools (SPMs) are primarily used for performing drilling-related operations and are widely used in mass production including automotive component manufacturing. Utilization of SPM is considerably widespread; however, this technology is relatively new and expensive. The important problems facing manufacturing industries wishing to utilize this technology is feasibility analysis to decide whether a SPM can be utilised for production of the given part and if it is feasible which SPM components would be appropriate. Since the cost of utilizing SPM is high, feasibility analysis must be performed before any investment on detailed design. This paper proposes a technical feasibility analysis method which assists in deciding whether SPM is applicable for machining a given part to achieve the highest productivity. The method is based on the framework which consists of relations between the desired part properties to the characteristics of the SPM components. These relations are captured as rules and constraints in an intelligent system which is implemented in Visual Basic. Applying the proposed method to a number of industrial parts shows that it is a very useful tool in deciding when SPMs should be utilized. 相似文献
56.
Crocker Jennifer; Canevello Amy; Breines Juliana G.; Flynn Heather 《Canadian Metallurgical Quarterly》2010,98(6):1009
Two longitudinal studies examined the associations between interpersonal goals (i.e., self-image and compassionate goals) and anxiety and dysphoria (i.e., distress). In Study 1, 199 college freshmen (122 women, 77 men) completed 12 surveys over 12 weeks. Compassionate goals predicted decreased distress, and self-image goals predicted increased distress from pretest to posttest when distress was assessed as anxiety, dysphoria, or a composite, and when the goals were worded as approach goals, avoidance goals, or a composite. In Study 2, 115 first-semester roommate pairs (86 female and 29 male pairs) completed 12 surveys over 12 weeks. Compassionate and self-image goals predicted distress in same-week, lagged-week, and pretest-to-posttest analyses; effects of compassionate goals remained significant when the authors controlled for several known risk factors. Having clear goals consistently explained the association between compassionate goals but not self-image goals and distress. Results supported a path model in which compassionate goals predict increased support given to roommates, which predicts decreased distress. Results also supported a reciprocal association; chronic distress predicted decreased compassionate and increased self-image goals from pretest to posttest, and weekly distress predicted decreased compassionate goals the subsequent week. The results suggest that compassionate goals contribute to decreased distress because they provide meaning and increase support given to others. Distress, in turn, predicts change in goals, creating the potential for upward and downward spirals of goals and distress. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
57.
Understanding the influence of demographic and psychological variables on retirement planning. 总被引:1,自引:0,他引:1
The authors examined the degree to which workers were engaging in financial, health, interpersonal/leisure, and work planning for retirement, exploring whether demographic and psychological variables inhibited or promoted planning in each of these domains. Planning in each domain was influenced by a unique set of variables. Goals emerged as a consistent and positive predictor of planning. Gender accounted for health and interpersonal/leisure planning, while work planning behavior was negatively predicted by income. Time perspective also helped to clarify the amount of retirement planning undertaken in the financial and interpersonal/leisure domains. Practical implications for designing retirement interventions are discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
58.
基于PBAC模型和IBE的医疗数据访问控制方案 总被引:1,自引:0,他引:1
医疗卫生领域形成的医疗大数据中包含了大量的个人隐私信息,面临着外部攻击和内部泄密的潜在安全隐患。传统的访问控制模型没有考虑用户访问目的在侧重数据隐私的访问控制中的重要作用,现有的对称、非对称加密技术又都存在密钥管理、证书管理复杂的问题。针对这些问题,提出了综合应用PBAC模型和IBE加密技术的访问控制方案,支持针对医疗数据密文的灵活访问控制。通过加入条件目的概念对PBAC模型进行扩展,实现了对目的树的全覆盖;以病患ID、条件访问位和预期目的作为IBE身份公钥进行病患数据加密,只有通过认证并且访问目的符合预期的用户才能获得相应的私钥和加密数据,从而实现对病患信息的访问。实验结果证明,该方案达到了细粒度访问控制和隐私保护的目的,并具有较好的性能。 相似文献
59.
从本体论的视角而言,中西方园林是两种性质完全不同的空间.二者服务于不同的目的,乃至于发展出不同的技术方法和表现形式.因此,造园目的是理解园林形式、园林创作的艺术与技术手段以及园林审美的基础,也是通达园林本质的起点.该文基于中国传统园林的发展脉络,辅以适当的文献资料,分析中国传统造园目的的变迁.并以此为线索,揭示中国传统园林的空间本质和园林空间演变的文化逻辑.最后,对中国传统园林的当代价值提出讨论. 相似文献
60.
简述了基于性能抗震设计思想,判断塔楼超限情况,确定抗震性能目标,并通过对某塔楼进行小 震弹性分析、中震不屈服分析和弹性时程补充分析,对其结构抗震性能进行评估.最后,总结该塔楼基于性能抗震设计的经验,为同类工程设计提供参考. 相似文献