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31.
Eva Sterner 《Construction Management & Economics》2013,31(1):21-30
The results of a survey show that both public and private building clients in Sweden, to varying extents, include environmental requirements in their procurement documents. The requirements identified have been classified into six categories primarily related to building and demolition waste, building material, contractors' environmental work, ecological aspects, construction work and other. One conclusion is that requirements regarding the separation of waste and a contractor's environmental policy are considered important, since they are stipulated in the majority of projects. Another finding is that requirements related to operation and especially to energy use are not considered sufficiently. Structured interviews were conducted with three of the clients who at that time of the survey had developed the most complete procurement documents with regard to environmental requirements. The aim of the interviews was to investigate how the stipulation of requirements, the evaluation of environmental aspects and the verification of environmental requirements were carried out. The conclusion drawn is that Swedish clients find the stipulation of requirements relatively uncomplicated, but find the evaluation of environmental impact, mainly related to selection of materials, problematic due to inadequate evaluation models. 相似文献
32.
极限编程(Extreme Programming,XP)是一种敏捷开发方法,适用于中小开发团队开发需求变更快的项目,现已成功地运用于中小型软件企业.本文在文献[4]的基础上,尝试在传统开发方法框架下,将XP应用于大型软件开发项目中.以期更为有效地解决大型软件项目中因需求不明确、变更过快而造成的项目失败等问题. 相似文献
33.
K. Cooper S.P. Abraham R.S. Unnithan L. Chung S. Courtney 《Journal of Visual Languages and Computing》2006,17(6):551
The Rational Unified Process is a comprehensive process model that is tailorable, provides templates for the software engineering products, and integrates the use of the Unified Modeling Language (UML); it is rapidly becoming a de facto standard for developing software. The process supports the definition of requirements at multiple levels. Currently, the early requirements, or goals, are captured in a textual document called the Vision Document, as the UML does not include a goal modeling diagram. The goals are subsequently refined into software requirements, captured in UML Use Case Diagrams. Given the well documented advantages of visual modeling techniques in requirements engineering, including the efficient communication and understanding of complex information among numerous diverse stakeholders, the need for an enhanced version of the Vision Document template which supports the visual modeling of goals is identified. Here, an Enhanced Vision Document is proposed which integrates two existing visual goal models: AND/OR Graph for functional goals and Softgoal Interdependency Graph for non-functional goals. A specific approach to establishing traceability relationships from the goals to the Use Cases is presented. Tool support has been developed for the Enhanced Vision Document template; the approach is illustrated using an example system called the Quality Assurance Review Assistant Tool. 相似文献
34.
利用UML获取功能需求的方法 总被引:11,自引:0,他引:11
在介绍了利用统一建模语言UML来进行功能需求分析的方法 ,并着重描述如何获取用例模型及用例之间的关系的同时 ,对需求分析在软件开发中的重要性也进行了阐述 ;并对UML和需求分析的基本原则做了简要介绍 相似文献
35.
Some real-time systems are designed to deliver services to objects that are controlled by external sources. Their services must be delivered on a timely basis, and the system fails when some services are delivered too late. In general, the timing requirements of the system may change when the states of the objects monitored by the system change. Such a system may fail if the timing requirements which it is designed to meet are erroneous. It may underutilize resources and consequently be costly or unreliable if the requirements are too stringent. Hence, one must identify how changes in object states call for changes in system requirements and how these changes should be incorporated into the design and implementation of the system. This paper first describes a methodology to determine timing requirements and to take into account requirement changes at runtime. The method is based on several timing requirement determination schemes. Simulation data show that these schemes are effective for applications such as mobile IP hand-offs. The paper then discusses how to incorporate this methodology in the system architecture and in the development process.
相似文献
J. W. S. LiuEmail: |
36.
In conventional model-oriented formal refinement, the abstract model is supposed to capture all the properties of interest in the system, in an as-clutter-free-as-possible manner. Subsequently, the refinement process guides development inexorably towards a faithful implementation. However, refinement says nothing about how to obtain the abstract model in the first place. In reality developers experiment with prototype models and their refinements until a workable arrangement is discovered.Retrenchment is a formal technique intended to capture some of the informal approach to a refinable abstract model in a formal manner that will integrate with refinement. This is in order that the benefits of a formal approach can migrate further up the development hierarchy. The basic ideas of retrenchment are presented, and a simple telephone system feature interaction case study is elaborated. This illustrates not only how retrenchment can relate incompatible and partial models to a more definitive consolidated model during the development of the contracted specification, but also that the same formalism is applicable in a re-engineering context, where the subsequent evolution of a system may be partly incompatible with earlier design decisions. The case study illustrates how the natural method of composing retrenchments can give results that are too liberal in certain cases, and stronger laws of composition are derived for systems possessing suitable properties. It is shown that the methodology can encompass more ad hoc and custom-built techniques such as Zave's layered feature engineering approach to applications exhibiting a feature-oriented architecture (such as telephony).
相似文献
R. BanachEmail: |
37.
Seong-Jin?Kim Kwon?SonEmail author Kyung-Hyun?Choi 《Journal of Mechanical Science and Technology》2003,17(12):1894-1903
It is necessary to have a dummy that describes the anthropometry of a victim with accuracy. This study presents three scaled
side impact dummies constructed for the use of MADYMO. They represent five, fifty and ninety-five percentile Korean males
ranged from the age of 25 through 39. Thirty-five anthropometric data were used to scale input files required for MADYSCALE.
Geometries, inertia, joints and other parameters for dummies were scaled based on the configurations of EuroSID-1. This study
proposes the lateral impact response requirements for head, thorax and pelvis of Korean side impact dummies. A lateral drop
impact test was conducted for the head at the height of 200 mm. Lateral pendulum impact tests were also carried out for thorax
and pelvis at three specific impact velocities. All these test results were obtained from simulation based on MADYMO. All
the procedures of the three tests followed the requirement of ISO/TR 9790. 相似文献
38.
杨泽军 《成都电子机械高等专科学校学报》2007,(3):62-65
着力建设高校校园和谐文化是中国特色社会主义文化的重要组成部分,因此,高校要进一步提高认识,明确建设高校校园和谐文化的基本要求,采取有效措施,加强高校校园和谐文化建设,把大学生培养成和谐发展的人,培养成为中国特色社会主义事业的建设者和接班人。 相似文献
39.
针对软件开发过程中如何有效地实施需求开发与需求管理的工作.从信息需求模型与信息寻求行为,到软件需求层次,再从需求工程的领域深入探讨需求开发与需求管理的工作。基于实践提出一套需求开发和管理的过程。 相似文献
40.
The Los Angeles Department of Water and Power (LADWP) operates a 600 mgd (2,270 ML/day) direct filtration water treatment plant which includes a 7,900 lb/day (149 kg/hr) ozonation system. Ozone is applied as a preoxidant for the purposes of disinfection and microflocculation. The ozonation system is unique in that high purity oxygen is generated on–site and is used as the feed–gas in a once–through system. The process was selected through competitive bids and evaluated for total present worth from 20–year life cycle costs which included capital plus energy expenses. Power consumption (and penalty) was valued at $6,500/kW. System power demand was measured at nine ozone production rates. A minimum specific energy of 6.5 kWh/lb (14.3 kWh/kg) of ozone was observed when generating ozone at a concentration between 5 and 6 % (wt) [65 and 80 g/m3; where the standard temperature and pressure are 70F (21.11 C) and 1 atm, respectively]. The test methodology and data assessment considerations were developed jointly by the owner and manufacturer, and produced results with practical significance beyond the performance testing objective. 相似文献