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151.
于文静 《广东输电与变电技术》2005,(3):58-59
工程建设投资控制是一个全方位多阶段的过程控制。尤其在设计阶段,通过贯穿于整个工程建设过程的优化设计来控制投资,能起到用最小投入获得最大产出的效果。 相似文献
152.
城市110kV及以上高压电缆的敷设里程迅速增长,在供电系统中负担起越来越重要的任务。为保证高压电缆工程的建设质量,建设者需要对电缆的技术特点、对工程施工管理有较深入的了解,采取科学的工程管理方法,才能提高高压电缆工程建设质量,满足电力系统供电可靠性的要求。 相似文献
153.
开发客户端免安装,免维护的图形化电力系统建模软件可为电力信息系统建设提供极大便利。系统采用Java语言开发用户侧图形界面,服务器侧采用Matlab语言编写计算程序;用户通过web浏览器访问服务器即可使用。 相似文献
154.
155.
In recent years, Industry 4.0 has been introduced as a popular term to describe the trend towards digitisation and automation of the manufacturing environment. Despite its potential benefits in terms of improvements in productivity and quality, this concept has not gained much attention in the construction industry. This development is founded in the fact that the far-reaching implications of the increasingly digitised and automated manufacturing environment are still widely unknown. Against this backdrop, the primary objective of this paper is to explore the state of the art as well as the state of practice of Industry 4.0 relating technologies in the construction industry by pointing out the political, economic, social, technological, environmental and legal implications of its adoption. In this context, we present the results of our triangulation approach, which consists of a comprehensive systematic literature review and case study research, by illustrating a PESTEL framework and a value chain model. Additionally, we provide recommendations for further research within a research agenda. 相似文献
156.
In order to extract a construction tree from a finite set of points sampled on the surface of an object, we present an evolutionary algorithm that evolves set-theoretic expressions made of primitives fitted to the input point-set and modeling operations. To keep relatively simple trees, we use a penalty term in the objective function optimized by the evolutionary algorithm. We show with experiments successes but also limitations of this approach. 相似文献
157.
Objectives of this study are to analyze the HAV exposures of chipping hammer operators from field measurements and to investigate the potential of various types of gloves in reducing the exposures. HAV exposures of twelve male operators were measured at four different operating conditions: bare hand, wearing normal workman gloves, wearing heavy workman gloves and wearing vibration reducing gloves. From the measurements, 8 h exposure values were determined and assessed against standards. The total vibration values were determined and effectiveness in vibration attenuation by gloves was compared. It was found that all most all operators, HAV exposure levels exceeded the exposure action value (EAV) and about 83% of the operators exceeded the exposure limit values (ELV). A reduction in the total vibration magnitude was observed with protective gloves: 8.3% with normal workman gloves, 14.6% with heavy workman gloves and 40% with vibration-reducing gloves. To confirm the effectiveness of the vibration reducing gloves, further field investigations are required with simultaneous measurements by considering parameters affecting HAV (i.e., hand forces and postures). 相似文献
158.
Today, construction planning and scheduling is almost always performed manually, by experienced practitioners. The knowledge of those individuals is materialized, maintained, and propagated through master schedules and look-ahead plans. While historical project schedules are available, manually mining their embedded knowledge to create generic work templates for future projects or revising look-ahead schedules is very difficult, time-consuming and error-prone. The rigid work templates from prior research are also not scalable to cover the inter and intra-class variability in historical schedule activities. This paper aims at fulfilling these needs via a new method to automatically learn construction knowledge from historical project planning and scheduling records and digitize such knowledge in a flexible and generalizable data schema. Specifically, we present Dynamic Process Templates (DPTs) based on a novel vector representation for construction activities where the sequencing knowledge is modeled with generative Long Short-Term Memory Recurrent Neural Networks (LSTM-RNNs). Our machine learning models are exhaustively tested and validated on a diverse dataset of 32 schedules obtained from real-world projects. The experimental results show our method is capable of learning planning and sequencing knowledge at high accuracy across different projects. The benefits for automated project planning and scheduling, schedule quality control, and automated generation of project look-aheads are discussed in detail. 相似文献
159.
Knowledge management is crucial for construction safety management. Widely collected and well-organized safety-related documents are recognized to be significant in raising the workers' security awareness and then to prevent hazards and accidents. To improve document processing efficiency, automatic information extraction plays an important role. However, currently, automatic information extraction modeling requires large scale training datasets. It is a big challenge for the engineering industry, especially for the fields which heavily rely on the experts’ knowledge. Limited data sources, and high time and labor costs make it not practical to establish a large-scale dataset. This work proposed a natural language data augmentation-based small samples training framework for automatic information extraction modeling. With the designed cross combination-based text data augmentation algorithm, the deep neural network can be employed to build up automatic information extraction models without large-scale raw data and manual annotations. Characters semantic coding is employed to avoid word segmentation and make sure that the framework can be utilized in different writing language systems. The BiLSTM-CRF model is adopted as the detection core to conduct character classification. Through a case study of two independent accident news report datasets analysis, the proposed framework has been validated. A reliable and robust automatic information extraction model can be established, even though with small samples training. 相似文献
160.