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排序方式: 共有8460条查询结果,搜索用时 31 毫秒
1.
分析了静电产生的原因,阐述了粉体含能材料生产中的静电起电现象、静电的危害、静电安全性评估标准以及建立在此标准基础上的静电放电危险的评价办法,提出了粉体含能材料在生产、运输中所需要采取的静电防护措施。  相似文献   
2.
This article presents a metaheuristic approach, the binary whale optimization algorithm (BWOA), to solve complex, constrained, non-convex, binary-nature profit-based unit commitment (PBUC) optimization problems of a price-taking generation company (GenCo) in the electricity market. To simulate the binary-nature PBUC problem, the continuous, real-value whale position/location is mapped into binary search space through various transfer functions. This article introduces three variants of BWOA using tangential hyperbolic, inverse tangent (arctan) and sigmoidal transfer functions. The effectiveness of the BWOA approaches is examined in test systems with different market mechanisms, i.e. an energy-only market, and energy and reserve market participation with different reserve payment methods. The simulation results are presented, discussed and compared with other existing approaches. The convergence characteristics, solution quality and consistency of the results across different BWOA variants are discussed. The superiority and statistical significance of the proposed approaches with respect to existing approaches is also presented.  相似文献   
3.
《Oil and Energy Trends》2019,44(10):29-30
Current data on net electricity production, as well as a breakdown of production by country. Updated on a monthly basis.  相似文献   
4.
《Oil and Energy Trends》2019,44(9):27-28
Current data on net electricity production, as well as a breakdown of production by country. Updated on a monthly basis.  相似文献   
5.
针对电力大数据流的异常检测问题,该文将流数据聚类算法与电力大数据相结合,针对现有流数据聚类算法不易存储全部数据、断电数据易丢失等问题,以及流数据聚类算法对于离线阶段聚类算法实时应答的要求,从数据的完整性、安全性以及流数据聚类算法的低时间复杂度的角度出发,对CluStream流数据聚类算法进行改进,提出流式K-means聚类算法。对在线阶段,使用Redis集群进行流数据的缓冲,并设计节点时间衰减策略,增大心跳消息中有效消息所占比例;对离线阶段聚类算法进行优化,使用最佳距离法确定初始聚类中心,减少迭代次数;最后,使用所提出的流式K-means聚类算法进行用户用电异常行为检测,实验结果表明,该算法能够很好的发现用户用电异常行为。  相似文献   
6.
The paper aims to investigate the determinants of household electricity consumption in Korea by using both the OLS regression and quantile regression. The results show that the effects of socio-demographic, dwelling, and electricity consumption characteristics on household electricity consumption may differ between two regressions and may differ across quantiles. We found that age group of household head, number of household, housing area, the number of household appliances, and refrigerator usage time were significant in all quantiles.  相似文献   
7.
针对多目标绿色可重入混合流水车间调度问题(RHFSP)的特点,在机器分配和工序排序的基础上引入分时电价机制,构建了以最小化最大完工时间、总能耗成本和碳排放为目标的绿色调度优化模型,提出了一种改进的多目标文化基因算法(MOMA)来求解该问题,通过数值实验验证了所设计的MOMA算法的可行性。实验结果表明MOMA算法在非劣解的收敛性、多样性和支配性指标方面都显著优于多目标蚁狮优化算法(MOALO)、多目标粒子群优化算法(MOPSO)和带精英策略的非支配排序遗传算法(NSGA-Ⅱ),四种算法的分布性指标无显著差异。所提出的模型能够使企业有效避开高电价时段作业,合理转移用电负荷,达到降低总用电成本和碳排放的目的。  相似文献   
8.
Hydrogen produced from renewable electricity through Power-to-Hydrogen can facilitate the integration of high levels of variable renewable electricity into the energy system. An electrolyser is a device that splits water into hydrogen and oxygen using electricity. When electricity is produced from renewable energy sources, electrolytic hydrogen can be considered to be green. At the same time, electrolysers can help integrate renewable electricity into power systems, as their electricity consumption can be adjusted to follow wind and solar power generation. Green hydrogen then also becomes a carrier for renewable electricity. Key green hydrogen production technologies, mostly PEM and alkaline electrolysers, are still further maturing, both in technical (efficiency), economical (CAPEX) and durability (lifetime) performance. Nonetheless, we will show in this contribution how fossil parity for green hydrogen, i.e. a Total Cost of Ownership (TCO) similar to grey H2 coming from todays CO2 intensive SMR processes, can already be achieved today. Moreover, this can be realised at a scale which corresponds to the basic units of renewable electricity generation, i.e. a few MW.  相似文献   
9.
Dirk Bühler 《Mauerwerk》2020,24(1):26-36
The Rank construction company and the introduction of brick vaults in Munich after 1945 The construction of vaults without scaffolding with thin bricks has a centuries‐old tradition, particularly in Spain and Italy. Since the beginning of the 19th century, it has been successfully spread mainly on the American double continent. The Rank Brothers construction company in Munich is known to date as one of those construction companies that began building with concrete in its home city very early on. New investigations, which were made possible above all by the provision of archive material by Paul Basiner, now point to an additional focus of this company's work. The architects and engineers of the company had been also able to familiarise themselves with this traditional Spanish brick‐vaulted construction method via the branch office in Spain, which was established from 1911 on. This knowledge was particularly in demand in the years following World War II, when the destroyed vaults had to be rebuilt with simple means and low material consumption. Together with Carl Sattler, who had become acquainted with similar construction methods in Italy, brick vaults were initially used to complete the construction of the Landeszentralbank in Munich. In the following years, Rank was able to provide many buildings in and around Munich with brick vaults. It was not until the 1960s that this construction technique went out of fashion and was thus somewhat forgotten.  相似文献   
10.
白俊  张雄君 《天然气工业》2019,39(7):127-132
2019年3月19日有关部门审议通过了《石油天然气管网运营机制改革实施意见》,组建国家油气管网公司是其中的核心内容。这标志着我国油气体制改革的实施进入了重点推进阶段。为了加深对于油气市场化改革的理解,从优化油气行业市场结构、促进油气管网基础设施互联互通和公平开放、推进油气价格市场化改革、推动国有油气企业转型升级发展等4个方面阐述了组建国家油气管网公司的积极意义,并就国家油气管网公司成立与油气体制改革、国有油气企业、管网投资建设、地方管网协同、油气价格、民生用气保障等相关问题进行了探讨。进而基于我国能源行业发展的特点、油气产业的现状和长期改革实践的经验和教训,提出了相关建议:(1)加快推进油气产业链上下游环节改革;(2)尽快推进提升监管能力的制度建设;(3)支持管网投资建设运营主体多元化;(4)做好国家管网和地方管网的统筹协调;(5)重点推进天然气基础设施整合及开放;(6)处理好管网公司组建涉及的资产、长期贸易协议、配套运行和监管规则等其他问题。以期更好地达成组建国家油气管网公司和推进油气体制改革的目标。  相似文献   
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