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排序方式: 共有8479条查询结果,搜索用时 31 毫秒
1.
Our empirical analysis focuses on the effect of regional policies on migration attraction factors in Europe. We employ a regression discontinuity design to assess the causal relationship between the reception of large amounts of public funds and migration flows in the EU-15 regions. In highly-subsidised regions, we find a large increase in the share of foreign citizens from less-developed countries when compared to low-subsidised regions with similar pre-treatment characteristics. The analysis shows that such an increase is due to the positive impact of the European regional policy on job market opportunities as well as the improvement of public goods supply. 相似文献
2.
Metropolitan strategic plans often focus on strengthening local employment opportunities to address the congestion and commuting issues threatening city sustainability. The success of such strategies relies on a more equitable distribution of jobs between sub-regions and can be comparatively benchmarked through one of the three related measures of employment self-sufficiency, self-containment or jobs-housing balance. However, in practice, planning policy implementation to meet these targets seldom reduces automobile commuting. This paper investigates self-containment across a range of occupation and industry types to highlight large differences in commuting and employment patterns through a case study of Perth’s Northwest sub-region, Western Australia. Its findings suggest the application of current sub-regional policy and targets within Perth may reinforce the wage and skill disadvantage of outer metropolitan sub-regions over the inner core. It recommends a more nuanced understanding of these measures taking into account the complex dynamics of both employment opportunities and commuting patterns across sub-regions of a city. 相似文献
3.
Raphael Muzondiwa Jingura Reckson Kamusoko 《Energy Sources, Part B: Economics, Planning, and Policy》2018,13(4):224-230
Jatropha curcas L. has emerged in recent times as a leading energy crop in sub-Saharan Africa with over 32 countries in the region involved in its cultivation. By 2008, five countries in the region (Senegal, Nigeria, Mali, Ethiopia, and Zimbabwe) had policies promoting Jatropha cultivation. These policies were not informed by empirical evidence arising from the performance of Jatropha in the region. This paper analyses performance data of Jatropha in the region with a view to synthesizing information that is useful for evidence-based policy formulation. Production data in terms of agronomic issues and seed yields are analyzed. The results show that most of the attributes generically associated with Jatropha have not been achieved in the region and there has been inadequate research to support Jatropha cultivation. Policies supporting cultivation of Jatropha need to be informed by these observations in order to promote viable cultivation of the crop. 相似文献
4.
Olga Filippova Yu Xiao Michael Rehm Jason Ingham 《Building Research & Information》2018,46(7):711-724
The marked increase in the awareness of earthquake risk following the Canterbury earthquakes in New Zealand offered a unique opportunity to investigate the economic effect of disaster-mitigation regulations on the commercial building stock. A difference-in-differences (DD) framework was used to determine whether earthquake risk has been capitalized into the property prices of buildings constructed prior to 1976, as a response to the national policy requiring assessment and strengthening (or demolition) of the existing earthquake-prone building stock. A negative externality is found in the policy announcement on affected (pre-1970s) office and retail buildings which caused office buildings to suffer a 12.5% stigma discount. However, retail properties were less impacted suffering a 2.3% stigma loss. The value of the commercial building stock has been affected by the policy. These findings provide policy-makers with timely evidence as to the economic effects of New Zealand’s earthquake-prone buildings policy. Facing losses in property value and financial responsibility for retrofitting their assets, building owners will be looking for a workable set of regulatory and non-regulatory incentives to encourage disaster risk management and protect the built environment. 相似文献
5.
Kaiying Cao Bing Xu Yi He Qingyun Xu 《International Transactions in Operational Research》2020,27(5):2270-2293
Carbon tax policy is widely adopted by many countries to curb carbon emissions. In the context of carbon tax policy, firms have more incentive to improve carbon reduction levels by reducing their carbon tax costs. However, firms need to bear carbon reduction costs that may cause shortage of capital. Thus, firms may face problems of financial constraints, which may demotivate firms to produce greener products. To address the decision‐making challenges of firms in the contexts of carbon tax policy and financial constraints, we consider a supply chain with a manufacturer who produces green products and a retailer who sells these products. Our study develops five models to investigate the two firms’ optimal wholesale price, carbon reduction level and ordering quantity, according to the manufacturer and retailer with or without financial constraints. Our goal in this study is to explore how carbon tax policy and banks’ interest rates affect the profits of the two firms, supply chain and consumer surplus. Certain managerial insights are obtained as follows. We demonstrate that carbon tax policy and banks’ interest rates demotivate the manufacturer to produce greener products and demotivate the retailer to order more products. If the interest rate to the manufacturer (retailer) is relatively low, then the manufacturer with financial constraint benefits (harms) the consumers compared with the retailer with financial constraint. Importantly, our analysis suggests that carbon tax policy harms the firms but benefits consumers, and the government in some conditions should reduce unit carbon tax. 相似文献
6.
Drawing on and developing Kingdon’s multiple streams analysis, this article examines the development of one aspect of the UK’s low cost home ownership programme: shared ownership. We demonstrate how key human and non-human policy entrepreneurs were able to set the agenda from 1973–1983 in favour of shared ownership; they neutralized the alternatives, while retaining some of their instruments; and solved a number of early problems by bringing key players into the programme. Our data-sets include a range of archival material and elite interviews. The policy entrepreneurs included John Stanley (who was the housing minister in the First Thatcher government), the National Federation of Housing Associations, and the Building Societies Association. Our development of the multiple streams analysis is to argue that documents, including the lease, act as policy entrepreneurs in their own right. The lease was central to the development of shared ownership and its transformation into a model lease enrolled other organizations, most critically the building societies. 相似文献
7.
鄂尔多斯盆地致密油水平井注水吞吐开发实践——以延长组长7油层组为例 总被引:1,自引:1,他引:0
针对致密油藏长水平井自然能量开发后期如何补充能量的难题,在致密油藏注水吞吐采油机理、可动油定量评价和矿场试验评价的基础上,提出了水平井注水吞吐的选井条件和技术政策:①初期产量较高、含水较低、有一定稳产期的水平井实施注水吞吐效果较好。②从经济性和储层非均质性两方面考虑,若水平井单段人工裂缝破裂压力差异小,则采用经济、操作简单的笼统注水吞吐方式;若水平井单段人工裂缝破裂压力差异较大,采用分段注水吞吐方式能够较好提高段间注水波及面积,缺点是成本较高。③鄂尔多斯盆地延长组长7油层组致密油自然能量开发转注水吞吐补充能量时机为地层压力保持水平降到原始地层压力的60%;注水吞吐注水后地层压力保持水平达到原始地层压力的110%;单段注水速度为10~20 m3/d;焖井时间为10~13 d (1 000 m3注水量);开井后水平井百米日产液量为1.5 m3/d。对鄂尔多斯盆地延长组长7油层组的50多个井组开展了致密油水平井注水吞吐试验,有效井组的比例达到了约70%,平均井组增油量为610 t,取得了较好的实施效果。 相似文献
8.
ABSTRACTIn India, of late, micro-irrigation has received considerable policy focus. However, as of 2017, only about 10% of the potential area is under micro-irrigation. The present study analyzes the pattern and equity issues of distribution of micro-irrigation in India and identifies the potential correlates. The regression analysis reveals that the stage of groundwater development and agro-climatic differences significantly influence the spread of micro-irrigation. The relatively low spread of micro-irrigation in states with over-exploited groundwater needs attention. Overall, the study points to the need to revamp the current micro-irrigation development programmes, which focus excessively on subsidy. 相似文献
9.
In many countries, distribution grid tariffs are being reformed to adapt to the new realities of an electricity system with distributed energy resources. In Europe, legislative proposals have been made to harmonize these reforms across country borders. Many stakeholders have argued that distribution tariffs are a local affair, while the European institutions argued that there can be spillovers to other countries, which could justify a more harmonized approach. In this paper, we quantify these spillovers in a simplified numerical example to give insight and an order of magnitude. We look at different scenarios, and find that the spillovers can be both negative and positive. To be able to quantify these effects, we developed a long-run market equilibrium model that captures the wholesale market effects of distribution grid tariffs. The problem is formulated as a non-cooperative game involving consumers, generating companies and distribution system operators in a stylized electricity market. 相似文献
10.
海绵城市建设PPP项目委托代理契约分析 总被引:1,自引:0,他引:1
针对海绵城市PPP(Public-Private Partnership)项目建设、运营管理问题,为了降低由于项目参与的各方掌握信息、地位的不对称而产生的道德风险、维护各参与方的合法权益,基于一定的前提假设,构建海绵城市建设PPP项目契约模型,利用优化理论分别从代理企业和政府方两个主体的效用对模型的各个参数相关关系进行了分析,并利用数值模拟讨论了监控机制各参数对政府方监控意愿的影响。最后,结合常德市海绵城市PPP项目建设的案例,分别分析在当前考核机制下项目在建设、运营期可能存在的问题,并提出了相应的对策以解决这些问题。结果表明:代理企业的监控和激励措施具有互补性,海绵工程项目风险来源广泛,企业为规避风险会偏好零风险的固定收益,设定监控机制能激励企业更加努力的工作。 相似文献