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61.
一次性医用手套是能够防止人们交叉感染的常用防护用品。随着新冠肺炎疫情在全球范围的迅速蔓延,疫情防控一线以及广大普通民众对一次性医用手套的需求与日俱增,其标准也受到广泛关注。本文对中国国家标准涉及一次性使用医用手套的4项产品标准进行了解读,并分析它们与国外同种产品标准间的对应关系以及重点指标的差异。  相似文献   
62.
ContextAgile enterprise architecture artefacts are initially architected at the high-level and the details of those artefacts iteratively evolve in small project increments. There is a need to model agile enterprise architecture artefacts both at the high and low detailed level for a particular context. ArchiMate is relatively a new high-level architecture modelling standard. There is a growing interest amongst organisations in applying ArchiMate for high-level agile enterprise architecture modelling. However, organisations are unsure how to effectively apply ArchiMate at high-level and integrate it with their existing low detailed level modelling standards in practice for supporting end-to-end agile enterprise architecture modelling.ObjectiveThis paper evaluates the applicability and integration of high-level ArchiMate modelling standard with the existing low-level modelling standards such as BPMN (Business Process Model and Notation), UML (Unified Modelling Language), FAML (FAME [Framework for Agent-Oriented Method Engineering] Language), SoaML (Service Oriented Architecture Modelling Language), and BMM (Business Motivation Model).MethodA qualitative questionnaire-based evaluation criteria has been developed based on the well-known and comprehensive The Open Group Architecture Framework (TOGAF). The evaluation criteria has been applied to evaluate the applicability and integration of the selected six modelling standards from the business, application, infrastructure and extension perspectives.ResultsEach modelling standard is different in scope. A single modelling standard usually does not provide the kind of support required by the agile enterprise architecture modelling. Based on the review results, a hybrid enterprise architecture modelling approach is proposed. This paper demonstrates the application of the proposed hybrid approach with the help of an agile enterprise architecture modelling case study.ConclusionIt is concluded that the ArchiMate does not replace the existing low-level modelling standards, rather it can be used in conjunction with low-level modelling standards. This calls for the adoption of hybrid and integrated approach for agile enterprise architecture modelling.  相似文献   
63.
PurposeThis study investigated the change in the fatality and severe injury risks in rear impacts with vehicle model years (MY) grouped prior to, during the phase-in and after the revision to FMVSS 301.MethodsFARS and NASS-CDS data were used to determine the injury risks of non-ejected occupants in light vehicles involving non-rollover, rear impacts. The data were analyzed by MY groups: 1996–2001, 2002–2007 and 2008+ to represent the years prior to, during the phase-in and post-revision phase-in of FMVSS 301. The 1996–2013 FARS data were analyzed for rear crashes defined by the initial crash direction (IMPACT1) and direction with most damage (IMPACT2) to the rear. Fatality risk was determined by the number of fatally injured occupants per all occupants with known injury status.The 1994–2013 NASS-CDS was analyzed for rear crashes defined by the damage area variable. The risk of severe injury (MAIS 4+F) was determined as the number of occupants with MAIS 4+F injury per all occupants with known injury status. The distribution of rear crashes was determined by impact location and crash severity. NASS-CDS electronic cases with 2008+ MY vehicles were analyzed to evaluate the vehicle and occupant performance.ResultsThe fatality risk was 20.6% in the 1996–2001, 17.3% in the 2002–2007 and 15.0% in the 2008+ MY vehicles using FARS with the initial crash direction variable (IMPACT1) to the rear. There was a 27.1% reduction in risk with post-FMVSS 301 vehicles 2008+ MY. The risk was 19.0%, 15.4% and 12.8% with the most damage variable (IMPACT2) to the rear. There was 32.8% reduction in risk with 2008+ MY vehicles.The NASS-CDS analysis showed that the risk of severe injury (MAIS 4+F) was 0.27 ± 0.05% for 1996–2001, 0.30 ± 0.13% for 2002–2007 and 0.08 ± 0.04% for 2008+ MY year vehicles. There was a 70.2% reduction in the risk for severe injury with 2008+ MY vehicles.The NASS-CDS case review of MAIS 4+F injury in rear impacts of 2008+ MY vehicles that comply with the revised FMVSS 301 indicated that the crashes were very severe and generally involved significant 2nd row intrusion.ConclusionsThe revision to FMVSS 301 has effectively reduced the risks for fatal and severe injury in vehicles compliant with the revision (2008+ MY). The reduction was 27.1–32.8% in fatality risk using FARS data and 70.2% in severe injury risk using the NASS-CDS when compared to vehicles prior to the phase-in of the revised FMVSS 301 (1996–2001 MY vehicles). It is not possible to parse the effects of other design changes in seats and restraint systems that also increased safety over the study years.  相似文献   
64.
Huge resources are invested in metrology and standards in the natural sciences, engineering, and across a wide range of commercial technologies. Significant positive returns of human, social, environmental, and economic value on these investments have been sustained for decades. Proven methods for calibrating test and survey instruments in linear units are readily available, as are data- and theory-based methods for equating those instruments to a shared unit. Using these methods, metrological traceability is obtained in a variety of commercially available elementary and secondary English and Spanish language reading education programs in the U.S., Canada, Mexico, and Australia. Given established historical patterns, widespread routine reproduction of predicted text-based and instructional effects expressed in a common language and shared frame of reference may lead to significant developments in theory and practice. Opportunities for systematic implementations of teacher-driven lean thinking and continuous quality improvement methods may be of particular interest and value.  相似文献   
65.
The paper aims to provide a source of information regarding the measurement of physical quantities, specifically those related to mechanical metrology. Since there is a lack of literature reviews referencing patents as a way of gathering useful information, we performed a systematic search for patents that could solve practical problems in this field. The methodology used focused on one of the most comprehensive patent database, Orbit.com, covering about 70,000,000 documents. This text gives a quick look at the fundamentals of the measurement literature and then points out the state-of-the-art concerning patents in the area of study. Additionally, data analysis shows the trends in the last five decades of patents about the subject. In total, 5686 documents are found and we compiled 10 examples of relevant patents for the quantities Length, Temperature and Mass, making this article a source of information for both scientific and non-scientific metrology community.  相似文献   
66.
This paper presents a new prospective metric for assessing the novelty and inventiveness of patents. It does this by using initial patent search reports and examiner's intuition about the impact of adverse citations on patent claim survival. The paper then demonstrates the metric by evaluating the quality of Switzerland's national patent stock using a selection model, finding that between 84 and 90% of the country's national patents would likely not survive examination at the European Patent Office. In doing so, it contributes to the larger literature on patent assessment, underscores the relevance of patent strategy in the observed characteristics of patents, and removes some of the ambiguity in the academic literature about backward citations.  相似文献   
67.
The embrittlement of metals exposed to hydrogen environments is well documented. With the deployment of hydrogen fuel cell vehicles in the consumer sector, there is a need to improve the engineering basis for the selection of materials of construction for equipment that stores and distributes high-pressure gaseous hydrogen. This brief overview summarizes publicly available guidance for evaluating materials compatibility with high-pressure gaseous hydrogen. Additionally, a new standard for measuring engineering data in gaseous hydrogen and evaluating materials suitability for service in gaseous hydrogen is introduced: the CHMC1 standard provides a general framework for qualifying materials for hydrogen service. The CHCM1 standard is unique in its broad scope and performance-based strategy for quantitatively assessing materials in their service environment and for the intended structural requirements.  相似文献   
68.
Spectrophotometers are routinely used for color measurement and color management in many commercial printing and proofing workflows. In the case of media containing optical brightening agents, ultraviolet (UV)‐induced fluorescence has led to poor levels of agreement between models from different manufacturers, and different models from the same manufacturer. A relevant standard, ISO 13655, has been revised and now clearly defines measurement modes and conditions for the UV component in spectrophotometers. ISO 13655:2009—Graphic Technology—Spectral Measurement and Colorimetric Computation for Graphic Arts Images now defines four measurement modes: M0, M1, M2, and M3. The intermodel difference between 10 commercially available spectrophotometers is evaluated for different substrate types in measurement modes (M0, M1, and M2) as allowed by each instrument. In particular, the authors compare devices using M0 legacy mode versus newer instruments that are compliant with the new M1 and M2 (UV‐included and UV‐excluded) measurement modes. A finding with significant practical applications is that there is greatly improved intermodel agreement between the new generation of ISO 13655‐compliant instruments in M1 (D50) mode when compared with the previous generation of hand‐held spectrophotometers. © 2016 Wiley Periodicals, Inc. Col Res Appl, 42, 27–37, 2017  相似文献   
69.
《Mauerwerk》2017,21(4):253-266
For the design of unreinforced masonry walls under lateral earth pressure according to DIN EN 1996‐3 [1], the active earth pressure is used, which is less than the earth pressure at rest. For the consideration of active earth pressure, a sufficient deflection of the wall is needed. It is unknown whether the deflections in reality are large enough to justify a reduction of the active earth pressure. Therefore a numerical model has been developed which considers the load‐bearing behaviour of masonry walls, with several boundary conditions being considered to estimate the effective earth pressure.  相似文献   
70.
基于造价工程师胜任力的视角,分析胜任力影响因素并构建评价体系和理论模型,结合问卷调查数据,运用结构方程分析造价工程师胜任力的关键影响因素及其对绩效的影响路径。研究表明,专业能力素质对绩效的影响最大,其次是综合管理素质,个人素质主要通过专业能力素质和综合管理素质两个中介变量对绩效产生间接影响。  相似文献   
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