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991.
溪洛渡水电站坝区初始地应力场反演分析研究   总被引:15,自引:7,他引:15  
初始地应力是岩土工程设计与施工所要考虑的重要因素之一。由实测地应力资料反演初始地应力场的方法很多,且各有优势。根据溪洛渡水电站工程坝区地应力的实测资料,采用有限单元法,结合多元线性回归方法、神经网络方法和遗传算法,分别反演求得整个坝区的初始地应力场。比较发现3种方法反演计算的结果非常接近,且均能模拟实际地应力场的分布规律。进一步的分析结果表明,由于溪洛渡水电站工程坝区在天然情况下岩体的屈服范围很小,坝区初始地应力场的非线性特征不明显,故线性回归分析方法即可满足要求。同时,研究还表明,在结果均能满足要求的前提下,回归分析方法与神经网络方法和遗传算法相比具有更方便快捷、易于掌握、唯一解的优势。  相似文献   
992.
The aim of this paper is to investigate the relationship-based factors that affect performance of general building projects in China. Thirteen performance metrics that may be used to measure the success level of construction projects are defined and categorized into four groups namely cost, schedule, quality and relationship performance. Fourteen risks inherent in relationships and 16 tools expected to facilitate relationship building that may affect project success are identified. Data of different projects were collected in China via a self-administered postal survey. Multiple linear regression models are developed to help explain the variance in different performance metrics. It has been found that ten risks and nine tools have either positive or negative influence on project performance to some different extents and in different project development process stages. Detailed explanations are made, especially to those variables bearing unexpected signs. It is recommended that firms in the Chinese construction industry manage the relationship-based factors that are significant in the MLR models so as to achieve project success.  相似文献   
993.
赵洁 《山西建筑》2007,33(26):359-360
从城市轨道交通工程管理的现状和特点出发,结合中国特大城市近期轨道交通建设计划,通过对项目信息平台的项目管理信息系统(PMIS)、项目总控信息系统(PCIS)以及项目信息门户(PIP)作用的详细介绍,提出了城市轨道交通工程“2+1”创新管理模式的必要性。  相似文献   
994.
南水北调西线一期工程的工程地质和岩石力学问题   总被引:8,自引:0,他引:8  
南水北调西线一期工程由“四坝、二堰、七洞”组成,年调水量40×108 m3。工程的最大难点在于深埋长隧洞的勘察、设计与施工。工程地质条件相对复杂,枢纽的建坝地质条件较好,块石料满足要求,库区淹没损失小。隧洞区的主要岩石类型为三叠纪的砂岩和板岩,局部出露有灰岩和岩浆岩。深埋长隧洞存在着诸多复杂的工程地质和岩石力学问题,但在目前的经济技术条件下是可以解决的,不存在制约西线工程实施的技术难关和地质条件。  相似文献   
995.
三峡船闸边坡岩体拉剪试验及强度准则研究   总被引:2,自引:0,他引:2  
三峡永久船闸边坡开挖后,卸荷和应力重分布使得岩体出现较大范围的拉应力区,且该区岩体多呈拉剪应力状态。为研究受拉区岩体拉剪强度准则,进行了室内岩石拉剪试验,但采用现场试验进行岩体拉剪强度准则研究则较为少见。通过在船闸区开展拉剪面尺寸为50 cm×50 cm的现场岩体拉剪试验,获得了不同拉应力时的岩体拉剪强度,岩体拉剪强度与拉应力关系呈明显的曲线特征。岩体拉剪强度准则研究结果表明:三峡花岗岩岩体拉剪强度准则宜采用莫尔强度准则的二次抛物线型来描述,其次为双曲线型,而双直线型偏差较大。进行边坡变形稳定分析时,对于拉剪应力区岩体则不宜采用直线型强度准则,更不能简单地采用压剪试验取得的直线型关系向拉应力区延伸方法确定岩体拉剪强度。  相似文献   
996.
南水北调西线一期工程在构造上位于青藏高原东部的巴颜喀拉地块内部,块体的四周边界以巨型走滑断裂和逆断裂为特征,构造运动非常强烈,是块体运动引发应力集中和释放能量的主要场所。但块体内部构造活动性较弱,仅发现甘德—阿坝断裂系北支断裂在阿坝盆地段的部分断裂、色达—洛若断裂和康勒断裂等晚更新世以来有过活动,且规模和运动强度远小于地块边界断裂。晚第四纪以来地块边界断裂的位移速率大多在7 mm/a以上,最大达18 mm/a,最小为1~2 mm/a,而输水隧洞附近最主要的活断层顺河断裂的位移速率仅为0.18 mm/a,相对地块边界断裂小1~2个数量级,可以认为工程场地处于构造相对稳定的地区。给出了阿坝盆地北缘断裂、顺河断裂等活断裂在工程使用期内最大设防的倾滑位移量,分别为0.67和2.62 m。  相似文献   
997.
结合三峡工程永久船闸陡高边坡特点,将高边坡岩体简化正交异性体,在对高边坡岩体开挖卸荷非线性力学特性充分认识的基础上,提出了各向异性非线性卸荷岩体的力学分析方法-变刚度分析理论,其计算成果与现场观测成果有的一致性。对三峡工程永久船闸陡高边坡岩体开挖分析表明高边坡岩体将产生较大的变形,与以往研究成果有数量级的差别。  相似文献   
998.
This paper aims at positioning organizational design as an important phenomenon in the field of project management with a high potential of contributing to organizational theory. While organizational design has been neglected by scholars of management and organizational theory, it has been of great interest to those from the project management field. This incongruence—comprising the focus of this study—calls for new insights on theorization in context. The paper provides a preliminary theoretical framework combining contingency theory, the historical approach and social theory to understand organizational design, both as a thing and as a process. It provides empirical evidence from three case studies in healthcare. Findings confirm the specificity of each design while at the same time adopting a similar temporal pattern. We take this opportunity to highlight the seminal work of Rodney Turner on project-based organization and design.

Executive summary

In this day and age, it is commonplace to assert that organizations are complex and that they change continuously over time. The complexity is said to exist, for example, in large organizations dealing with multiple competing projects while at the same time performing their regular operations. The concept of organizational design refers to both the resulting organization (the thing) and the process of performing the design. The field of project management has made many theoretical contributions to organizational design; yet it has also created confusion by introducing a plurality of terms for describing and understanding such organizations.Organizational design is increasingly a topic in the literature from management and organizational theory and, especially, from project management. A review of the literature from both fields demonstrates that contingency theory is still considered as a major theoretical foundation for situating the organization within its context. The review also points to an increasing interest in social perspectives taking into account politics, organizational dynamics, paradoxes and pluralism. In addition, it shows an opportunity for scholars in project management to contribute to management and organizational theory.This research proposes a pluralist theoretical framework for tackling contingency theory with the historical approach and social theory.The empirical setting is comprised of complex large organizations—in this case, three university hospitals engaged in major organizational transformations—that are challenged to pursue their regular operations while undertaking multiple completing projects. Interestingly, the three hospitals are from the same geographical region. The organizational design was thus a crucial question and, in light of the complexity, no one-size-fits-all type of solution was strived for.Results confirmed the prevalence of individual organizational design rather than mimetism, or homogenization, between the three hospitals. Being in the same region, the heads of the respective project management offices met on a number of occasions to exchange about their challenges and solutions. Nevertheless, in the end each hospital made an individual decision regarding its organizational design.The study also identified organizational design as an ongoing process, introducing the concept of trajectory to illustrate how projects and organizational design change over time. In doing so, we observed a pattern where reflection and sense-making took place before engaging in any specific decision regarding the organizational design.The theoretical contribution of this research is to demonstrate the potential of pluralist theoretical frameworks for understanding complex phenomena such as organizational design in the context of managing multiple projects. More specifically, the process view of organizational design was found to reveal new insights that would have remained hidden otherwise.From a practical view, our research challenges certain utopian assumptions regarding the stability and replicability of a one-size-fits-all model in organizational design. Instead, we recommend developing an in-depth understanding of an organization's specific context by means of sense-making activities. The latter should be performed in an ongoing approach to ensure that the organizational design evolves in keeping with its environment.  相似文献   
999.
三峡库区奉节河段库岸蓄水再造研究   总被引:18,自引:1,他引:18  
通过二维水流泥沙数模计算,分析了三峡库蓄水后棒节河段的泥沙淤积量、流场、近岸流速及浪高等的变化;探讨了岸坡可能的3种再造形式;冲刷塌岸、整体滑移、岩坡崩塌;建立了库岸冲刷塌岸的预测模型,并进行了预测;计算分析了不同水位、冲刷淤积、地震等工况下典型滑坡的稳定性变化规律;最后,对库岸再造的工程防治措施提出了建议。  相似文献   
1000.
基于Web的重大工程项目管理信息系统应用研究   总被引:7,自引:0,他引:7  
本文介绍了基于Web的重大工程项目管理信息系统的开发思路、主要功能及不足之处 ,与以往的项目管理系统相比 ,本系统突出了集成管理和系统设计的思想  相似文献   
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