全文获取类型
收费全文 | 24441篇 |
免费 | 628篇 |
国内免费 | 426篇 |
专业分类
电工技术 | 707篇 |
技术理论 | 2篇 |
综合类 | 925篇 |
化学工业 | 2079篇 |
金属工艺 | 1363篇 |
机械仪表 | 3068篇 |
建筑科学 | 5102篇 |
矿业工程 | 511篇 |
能源动力 | 761篇 |
轻工业 | 1270篇 |
水利工程 | 304篇 |
石油天然气 | 686篇 |
武器工业 | 136篇 |
无线电 | 1297篇 |
一般工业技术 | 1861篇 |
冶金工业 | 827篇 |
原子能技术 | 191篇 |
自动化技术 | 4405篇 |
出版年
2024年 | 30篇 |
2023年 | 166篇 |
2022年 | 250篇 |
2021年 | 384篇 |
2020年 | 382篇 |
2019年 | 247篇 |
2018年 | 293篇 |
2017年 | 307篇 |
2016年 | 504篇 |
2015年 | 583篇 |
2014年 | 1183篇 |
2013年 | 1262篇 |
2012年 | 1490篇 |
2011年 | 1678篇 |
2010年 | 1270篇 |
2009年 | 1268篇 |
2008年 | 1107篇 |
2007年 | 1490篇 |
2006年 | 1534篇 |
2005年 | 1423篇 |
2004年 | 1230篇 |
2003年 | 1269篇 |
2002年 | 1063篇 |
2001年 | 808篇 |
2000年 | 766篇 |
1999年 | 716篇 |
1998年 | 584篇 |
1997年 | 455篇 |
1996年 | 390篇 |
1995年 | 330篇 |
1994年 | 241篇 |
1993年 | 193篇 |
1992年 | 145篇 |
1991年 | 105篇 |
1990年 | 71篇 |
1989年 | 66篇 |
1988年 | 48篇 |
1987年 | 28篇 |
1986年 | 19篇 |
1985年 | 29篇 |
1984年 | 27篇 |
1983年 | 16篇 |
1982年 | 7篇 |
1981年 | 8篇 |
1980年 | 6篇 |
1979年 | 6篇 |
1978年 | 3篇 |
1976年 | 6篇 |
1975年 | 4篇 |
1971年 | 3篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
971.
972.
973.
地理设计简述:概念、框架及实例 总被引:2,自引:0,他引:2
简要地介绍了地理设计的概念、框架并列举了一个实际的应用实例。首先追溯了地理设计的历史渊源,其后讲解了它的关键概念。地理设计并非是一个新的学科,而是一种新的理念,并在技术上借助地理信息系统、整合并协调诸如城市规划、风景园林、建筑设计等传统学科的一种集成的努力。地理设计为改善甚至拯救环境提供了一个有力的手段。以地理位置为基础的规划设计是地理设计的基础。讲解了地理设计框架的核心内容,即四方参与及六大过程往复循环发展,引用了一个运用地理设计原理在城市规划方面的应用的近期实例。 相似文献
974.
As one of the measures for slope fast reinforcement, micropiles are always designed as a group. In this paper, an analytic model for the ultimate resistance of micropile is proposed, based on a beam–column equation and an existing p–y curve method. As such, an iterative process to find the bending moment and shear capacity of the micropile section has been developed. The formulation for calculating the inner force and deflection of the micropile using the finite difference method is derived. Special attention is given to determine the spacing of micropiles with the aim of achieving the ultimate shear capacity of the micropile group. Thus, a new design method for micropiles for earth slope stabilization is proposed that includes details about choosing a location for the micropiles within the existing slope, selecting micropile cross section, estimating the length of the micropile, evaluating the shear capacity of the micropiles group, calculating the spacing required to provide force to stabilize the slope and the design of the concrete cap beam. The application of the method to an embankment landslide in Qinghai province, China, is described, and monitoring data indicated that slope movement had effectively ceased as a result of the slope stabilization measure, which verified the effectiveness of the design method. 相似文献
975.
Peter E. D. Love Purnendu Mandal Jim Smith Heng Li 《Construction Management & Economics》2013,31(5):567-574
Rework that is experienced in construction projects is often caused by errors made during the design process. Factors that contribute to design errors are identified and used to design and develop a systems dynamics model, which is used to simulate a number of practical scenarios that can be used to reduce design errors and rework. The model presented in this paper can enable design and project managers to understand better the process of design documentation and how design errors occur in construction projects. 相似文献
976.
Hemanta Doloi 《Construction Management & Economics》2013,31(11):1181-1196
The novated design and construct (ND&C) contract is one of the increasingly preferred options among developers of large commercial and residential projects across Australia. As a consequence of novation, the design team's obligation to the client gets transferred to the contractor who becomes responsible for carrying out the detailed design work at a later stage of project life cycle. Subsequently, there are some inherent factors that can depict the effectiveness of how all parties in the process interact leading to a successful delivery of project through ND&C contracts. A common set of 31 influencing attributes have been identified through a systematic research approach and their relative significance and impacts have been determined based on a structured questionnaire survey in selected construction projects. By performing the factor analysis, a total of eight factors significant to ND&C contracts were extracted, namely (1) impact of initial design; (2) client's involvements in post novation design; (3) selection of design team; (4) contractor's obligation; (5) morale in post novation; (6) experience of design team; (7) relationship between contractor and design team; and (8) expertise of DT in ND&C projects. With a clear understanding of the roles of clients, design team and the contractors, these findings could potentially contribute to develop a company's procedures or enhance existing knowledge in relation to the ND&C procurement approach. 相似文献
977.
The success of the design and build (D&B) procurement route could be undermined by issues arising from the rigid professional cultures of individual participants within project workgroups. These have the potential to inhibit the achievement of a key espoused benefit of D&B procurement, i.e. that it promotes the integration of the design and construction processes for improved project performance. Cultural non-interoperability is identified as a significant potential barrier to effective change management, and to the achievement of innovation within the design and construction processes. This note argues that project responsibilities, which currently are delineated along professional identity lines, produce design and construction solutions that fail to fulfil the potential of D&B procurement. It is suggested that addressing cultural interoperability will require a fundamental and long term reshaping of the industry's structure, beginning with the professional bodies and the higher education system that underpins their future membership. 相似文献
978.
Helen Clare Lingard Tracy Cooke Nick Blismas 《Construction Management & Economics》2013,31(5):367-382
Drawing upon an empirical analysis of the design and construction of a food processing facility, a theoretical understanding of the impact of design decision-making on the occupational health and safety (OHS) of construction workers is developed. It is argued that current policy and legislative approaches to Construction Hazard Prevention through Design (CHPtD) are inherently limited because they do not adequately reflect the socio-material complexity of decision-making in construction design. Specifically, the simplistic attribution of responsibility to a single socio-technical actor, ‘the designer’, does not reflect the multiple and disparate influences that impact upon OHS outcomes. Nor do existing CHPtD policy frameworks, management processes and tools recognize the manner in which the interactions and associations between relevant project stakeholders and various non-human artefacts shape (and are also influenced by) the evolution of design decisions. Drawing on actor-network theory (ANT) and using embedded units within a case study approach, the interactions between human actors and non-human artefacts are explored in relation to the design of four components of the food processing facility. The way in which design decisions unfolded and shaped OHS experiences during the construction stage of the project is revealed. The research highlights limitations inherent in current approaches to the management of CHPtD and the need to develop a more robust theoretically based approach to integrating OHS considerations into construction design practice. 相似文献
979.
This paper focuses on the management dimension of small building works. The paper presents a subset of findings from a major research study, supported by governmental and industry based sources, which investigated the efficiency and effectiveness of procurement methods, organizational systems and management approaches to small works and minor maintenance projects. The findings indicate that management for small works must be exerted at two levels. One is within the organization of the works themselves. The second is the development of a framework and organization which considers the implication of the works upon the organization's ongoing business. Effective small works management requires that an organization responds promptly to an identified situation, determines the cost of the work, ensures that the work is undertaken successfully, and gives value for money within the context of the organization's current business circumstance. 相似文献
980.
Abdulaziz A. Bubshait Gulam Farooq M. Osama Jannadi Sadi A. Assaf 《Construction Management & Economics》2013,31(6):799-809
Design organizations play a major role in the construction industry: they are the media that transfer the requirements of the client to the contractor and ensure that they are met. Thus they need to provide a high quality of service to ensure that their client's project achieves the best possible standards of cost, time and quality. Seventy quality practices (QP) were identified as having a bearing on the quality of service provided by the local design organizations. These quality practices were grouped into fifteen sections termed quality sections (QS). The prevalence of these practices among the local design organizations was surveyed and determined. The results indicate a significant need for improvement in the quality sections ‘working relationship’, ‘employee training and education’, and ‘performance quality audit’. The study reveals the need for the establishment of a design code, and evaluation standards for local design organizations. 相似文献