全文获取类型
收费全文 | 2910篇 |
免费 | 149篇 |
国内免费 | 81篇 |
专业分类
电工技术 | 57篇 |
技术理论 | 3篇 |
综合类 | 774篇 |
化学工业 | 327篇 |
金属工艺 | 33篇 |
机械仪表 | 97篇 |
建筑科学 | 319篇 |
矿业工程 | 61篇 |
能源动力 | 58篇 |
轻工业 | 407篇 |
水利工程 | 59篇 |
石油天然气 | 38篇 |
武器工业 | 5篇 |
无线电 | 125篇 |
一般工业技术 | 128篇 |
冶金工业 | 284篇 |
原子能技术 | 9篇 |
自动化技术 | 356篇 |
出版年
2024年 | 14篇 |
2023年 | 30篇 |
2022年 | 53篇 |
2021年 | 66篇 |
2020年 | 70篇 |
2019年 | 51篇 |
2018年 | 43篇 |
2017年 | 49篇 |
2016年 | 76篇 |
2015年 | 78篇 |
2014年 | 180篇 |
2013年 | 221篇 |
2012年 | 217篇 |
2011年 | 240篇 |
2010年 | 228篇 |
2009年 | 197篇 |
2008年 | 198篇 |
2007年 | 201篇 |
2006年 | 184篇 |
2005年 | 150篇 |
2004年 | 121篇 |
2003年 | 104篇 |
2002年 | 78篇 |
2001年 | 56篇 |
2000年 | 58篇 |
1999年 | 35篇 |
1998年 | 20篇 |
1997年 | 17篇 |
1996年 | 10篇 |
1995年 | 11篇 |
1994年 | 11篇 |
1993年 | 11篇 |
1992年 | 9篇 |
1991年 | 2篇 |
1990年 | 5篇 |
1989年 | 3篇 |
1988年 | 3篇 |
1987年 | 6篇 |
1986年 | 3篇 |
1985年 | 3篇 |
1979年 | 2篇 |
1978年 | 2篇 |
1975年 | 2篇 |
1963年 | 2篇 |
1961年 | 3篇 |
1960年 | 2篇 |
1958年 | 3篇 |
1957年 | 2篇 |
1956年 | 3篇 |
1955年 | 1篇 |
排序方式: 共有3140条查询结果,搜索用时 109 毫秒
1.
Smart grid has opened up a new role of “prosumer” in an energy value network, transforming many conventional energy consumers into prosumers, who not only generate green energy but also share the surplus with utilities and other consumers. The concept of a goal-oriented prosumer community group (PCG) has emerged recently as an effective way to fulfill sustainable energy exchange. Such community-based energy sharing networks comprise multiple irreconcilable objectives such as demand constraints, cost constraints, and income maximization. In many cases, one goal may be achievable only at the expense of other goals. This necessitates the development of an effective framework to manage the multiple goals and reduce the gap with their achievement levels. Therefore, in this research paper, an effective framework is developed to negotiate among the multiple goals and thus to define optimal mutual goals for each PCG in a more sustainable manner using multiple-criteria goal programming techniques. Simulation results are presented to illustrate how the methods work in practical situations, where each of the objective measure is given a target value and the unwanted deviations from this set are minimized in an achievement function. 相似文献
2.
3.
4.
5.
Camacho Christopher J.; Higgins E. Tory; Luger Lindsay 《Canadian Metallurgical Quarterly》2003,84(3):498
People experience regulatory fit (E. T. Higgins, 2000) when the strategic manner of their goal pursuit suits their regulatory orientation, and this regulatory fit feels right. Fit violation feels wrong. Four studies tested the proposal that experiences of fit can transfer to moral evaluations. The authors examined transfer of feeling wrong from fit violation by having participants in a promotion or prevention focus recall transgressions of commission or omission (Studies 1 and 2). Both studies found that when the type of transgression was a fit violation, participants expressed more guilt. Studies 3 and 4 examined transfer of feeling right from regulatory fit. Participants evaluated conflict resolutions (Study 3) and public policies (Study 4) as more right when the means pursued had fit. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
6.
金沙江防洪(库容)规划的探讨 总被引:1,自引:0,他引:1
在分析长江灾害洪水特征的基础上,全面深入地研究了全沙江水库的防洪库客、防洪目标、防洪特点和调度原则,并对防洪库容的作用进行了估算和分析。从多方面比较了虎跳峡高坝方案与低坝方案,结果表明:高坝方案的效益明显高于低坝方案,而两者所需付出的代价相差不大。 相似文献
7.
Nusslock Robin; Abramson Lyn Y.; Harmon-Jones Eddie; Alloy Lauren B.; Hogan Michael E. 《Canadian Metallurgical Quarterly》2007,116(1):105
On the basis of the behavioral approach system (BAS) dysregulation theory of bipolar disorder, this study examined the relation between occurrence of a BAS activation-relevant life event--goal striving--and onset of hypomanic and depressive episodes and symptoms. In particular, the authors examined the relation between preparing for and completing final exams (a goal-striving event) and onset of bipolar spectrum episodes and symptoms in college students with bipolar II disorder or cyclothymia (i.e., "soft" bipolar spectrum conditions). One hundred fifty-nine individuals with either a bipolar spectrum disorder (n=68) or no major affective psychopathology (controls; n=91) were further classified on the basis of whether they were college students (i.e., completed final exams). Consistent with the BAS dysregulation theory, preparing for and completing final exams was associated with an increase in hypomanic but not depressive episodes and symptoms in individuals with a soft bipolar spectrum diagnosis. Furthermore, self-reported BAS sensitivity moderated the presence of certain hypomanic symptoms during final exams. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
8.
朱颖 《湖南冶金职业技术学院学报》2004,(3)
从能力培养的角度较全面、系统地阐述了教师组织课堂教学的基本方法和手段。并针对职业教育的培养要求及学生的心理特点,在有效整合学校各种教学资源、努力实现学生知识结构与能力培养和谐统一方面进行了一些有益探索和实践。 相似文献
9.
机械化栽培甜菜平均单产33.18吨/公顷,比人工栽培生产田提高52.03%;平均含糖15.5度,比人工栽培生产田提高1.09度;平均技术效果138.2元/公顷;经济效果1588.8元/公顷;创造社会经济效益24.47万元。 相似文献
10.
目前高职高专建筑设备专业在人才培养方面主要存在着目标定位不准及理论教学与实践教学学时分配不当等问题,对此提出高等职业技术学院建筑设备专业的人才培养目标和培养建议。 相似文献