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61.
This study seeks to improve the geometrical distribution of bricks to optimise the equivalent thermal transmittance of a wall built of Termoarcilla® ECO 29 voided clay bricks, using calculations according to Spanish UNE [1], AENOR [10], European EN [6], [7], [8] and [9] and international ISO [11] and [12] standards.The objective is to study improvements in the wall's thermal conductivity, always remembering the limitations imposed by the manufacturing process. Simulations are made using a finite elements application [14].It is concluded that, within the possibilities allowed by the manufacturing process, with non-rectangular voids the heat flux has to cross a higher number of voids, which improves its thermal properties. A rhomboid layout of voids with the longer diagonal at right angles to the heat flux is the best internal void layout. If the internal perforations are also extended to the end of the tongue and groove, the direct thermal bridge in this type of brick is broken.Finally, a 290 mm wide brick with 25 rows is obtained with the geometrical properties described above which shows an improvement of almost 16% over the original ECO 29 brick, performing well in all climatic areas of Spain, with a full-bed mortar joint 30 mm thick. 相似文献
62.
In formation of building external envelope, as two important criteria, climatic data and wall types must be taken into consideration. In the selection of wall type, the thickness of thermal insulation layer (di) must be calculated. As a new approach, this study proposes determining the thermal insulation layer by using artificial neural network (ANN) technique. In this technique five different wall types in four different climatic regions in Turkey have been selected. The ANN was trained and tested by using MATLAB toolbox on a personal computer. As ANN input parameters, Uw, Te,Met, Te,TSE, Rwt, and qTSE were used, while di was the output parameter. It was found that the maximum mean absolute percentage error (MRE, %) is less than 7.658%. R2 (%) for the training data were found ranging about from 99.68 to 99.98 and R2 for the testing data varied between 97.55 and 99.96. These results show that ANN model can be used as a reliable modeling method of di studies. 相似文献
63.
针对电子邮件复杂网络中的社团发现问题,将具有良好聚类性能的DBSCAN算法引入电子邮件网络社团发现。基于对该算法的分析,研究了电子邮件网络社团发现的系统架构及算法实现流程。最后通过对安然邮件语料集的测试验证了DBSCAN算法在社团发现中的可行性。 相似文献
64.
Mean wind pressure coefficients (Cp) are key input parameters for air infiltration and ventilation studies. However, building energy simulation and stand-alone airflow network programs usually only provide and/or use a limited amount of Cp data, which are based on several assumptions. An important assumption consists of using surface-averaged Cp values instead of local Cp values with a high resolution in space. This paper provides information on the uncertainty in the calculated airflow rate due to the use of surface-averaged Cp data. The study is performed using published empirical data on pressure coefficients obtained from extensive wind tunnel experiments. The uncertainty is assessed based on the comparison of the airflow rate (?) calculated using the surface-averaged Cp values (?AV) and the airflow rate calculated using local Cp values (?LOC). The results indicate that the uncertainty with a confidence interval of 95% is high: 0.23 ?AV < ?LOC < 5.07 ?AV. In cases with the largest surface-averaged ΔCp, the underestimation or overestimation is smaller but not negligible: 0.52 ?AV < ?LOC < 1.42 ?AV. These results provide boundaries for future improvements in Cp data quality, and new developments can be evaluated by comparison with the uncertainty of the current methods. 相似文献
65.
设计针对外在限制条件进行理性分析,对建筑系统进行统筹设计和优化组合从而确定基本的设计框架,并通过发挥创造性思维形成技术整合的亮点,营造了一个既尊重环境、又富于个性的校园建筑。 相似文献
66.
由于伴随着持续发展的自动控制、现代通信、计算机技术,这就逐步产生智能化建筑,所谓的智能小区则是扩展与延伸智能化大楼,人们往往借助优化考虑小区建筑群的服务、结构、管理、系统这四个基本要素,提供出一个便利、舒适、投资合理、安全、温馨、效率高的人居环境。以便可以将当前我国住宅建设科技含量增强与发展加快的要求。 相似文献
67.
68.
The construction industry is based on craftsmanship. Quality control and assurance procedures applied in manufacturing cannot usually be readily applied in construction, where there are higher degrees of uniqueness in each project. One category of companies, industrialized housebuilders, is attempting to bridge some of the gaps between construction and manufacturing. These companies prefabricate building modules for later assembly at the building site. Since they are wholly responsible for large parts of the building process, these companies have greater opportunities to control and improve quality in a more consistent way than ordinary construction companies. Thus, it could be hypothesized that the frequency and severity of defects should be lower in industrialized housing than in ordinary construction. The aim of the study presented here is to examine this hypothesis by measuring and characterizing defects in industrialized housing. The design and manufacturing processes at two Swedish timber module prefabrication firms has been analysed through interviews, site visits and document reviews. Quality audits from three phases of the building process were compiled, analysed and categorized to provide statistical measures of defects in industrialized housing. The results show that the case study companies are better in terms of product quality than conventional housing. 相似文献
69.
文章介绍了都柏林格拉夫顿事务所设计的爱尔兰财政部办公楼.设计从城市的角度出发,注重呼应历史遗存和延续建筑传统,同时采用有效的建筑设计策略赋予室内交通和使用空间以新的意义,并给予周围环境积极有效的界面设计.设计创造了一个崭新的政府办公建筑,在延续传统、呼应城市文脉的同时,塑造了办公楼亲切开放民主的建筑形象. 相似文献
70.
在楼房爆破拆除中,根据待拆楼房的围围环境,采用了沿楼房对角线方向定向倾倒拆除的方案,并取得了成功。文中介绍了爆破方案、布孔方法及具体的爆破参数。 相似文献