全文获取类型
收费全文 | 4214篇 |
免费 | 144篇 |
国内免费 | 101篇 |
专业分类
电工技术 | 100篇 |
技术理论 | 2篇 |
综合类 | 181篇 |
化学工业 | 523篇 |
金属工艺 | 259篇 |
机械仪表 | 360篇 |
建筑科学 | 596篇 |
矿业工程 | 275篇 |
能源动力 | 260篇 |
轻工业 | 152篇 |
水利工程 | 25篇 |
石油天然气 | 110篇 |
武器工业 | 14篇 |
无线电 | 146篇 |
一般工业技术 | 267篇 |
冶金工业 | 275篇 |
原子能技术 | 42篇 |
自动化技术 | 872篇 |
出版年
2024年 | 11篇 |
2023年 | 88篇 |
2022年 | 112篇 |
2021年 | 154篇 |
2020年 | 142篇 |
2019年 | 91篇 |
2018年 | 78篇 |
2017年 | 83篇 |
2016年 | 124篇 |
2015年 | 113篇 |
2014年 | 244篇 |
2013年 | 194篇 |
2012年 | 283篇 |
2011年 | 313篇 |
2010年 | 196篇 |
2009年 | 203篇 |
2008年 | 177篇 |
2007年 | 242篇 |
2006年 | 226篇 |
2005年 | 197篇 |
2004年 | 169篇 |
2003年 | 150篇 |
2002年 | 136篇 |
2001年 | 90篇 |
2000年 | 95篇 |
1999年 | 111篇 |
1998年 | 89篇 |
1997年 | 71篇 |
1996年 | 51篇 |
1995年 | 47篇 |
1994年 | 35篇 |
1993年 | 26篇 |
1992年 | 22篇 |
1991年 | 14篇 |
1990年 | 8篇 |
1989年 | 5篇 |
1988年 | 10篇 |
1987年 | 5篇 |
1986年 | 9篇 |
1985年 | 4篇 |
1984年 | 7篇 |
1983年 | 6篇 |
1982年 | 11篇 |
1981年 | 5篇 |
1980年 | 2篇 |
1979年 | 4篇 |
1978年 | 2篇 |
1963年 | 1篇 |
1958年 | 1篇 |
1954年 | 1篇 |
排序方式: 共有4459条查询结果,搜索用时 0 毫秒
51.
52.
53.
Response time (RT) of Networked Automation Systems (NAS) is affected by timing imperfections induced due to the network, computing and hardware components. Guaranteeing RT in the presence of such timing imperfections is essential for building dependable NAS, and to avoid costly upgrades after deployment in industries.This investigation proposes a methodology and work-flow that combines modelling, simulation, verification, experiments, and software tools to verify the RT of the NAS during the design, rather than after deployment. The RT evaluation work-flow has three phases: model building, modelling and verification. During the model building phase component reaction times are specified and their timing performance is measured by combining experiments with simulation. During the modelling phase, component based mathematical models that capture the network architecture and inter-connection are proposed. Composition of the component models gives the NAS model required for studying the RT performance on system level. Finally, in the verification step, the NAS formal models are abstracted as UPPAAL timed automata with their timing interfaces. To model timing interfaces, the action patterns, and their timing wrapper are proposed. The formal model of high level of abstraction is used to verify the total response time of the NAS where the reactions to be verified are specified using a subset of timed computation tree logic (TCTL) in UPPAAL model checker. The proposed approach is illustrated on an industrial steam boiler deployment. 相似文献
54.
提出基于工业以太环网以光纤为传输介质的矿井安全监控系统的设计方案,设计基于以太环网的煤矿工业控制网络的实用模型,重点介绍系统的总体结构,以及方案的具体实施.该方案解决安全监控系统在煤矿复杂环境下的信息传输问题. 相似文献
55.
针对带有输出关联约束的工业过程,提出一种确定其稳态优化控制的算法.首先通过对数变换将原问题转化为一个等价而且可在对数空间求解的优化控制问题;然后为避免事先选择一个合适罚系数的困难,在算法中引入了目标函数的线性化形式.该优化算法不仅能收敛到正确的系统最优解,而且可用现有的二次规划算法计算.应用简单的滤波技术,改善了算法在有量测噪声情况下的性能.仿真结果表明,所提出的优化算法是有效的. 相似文献
56.
大红山铜矿原矿输送控制系统改造 总被引:1,自引:0,他引:1
通过分析大红山铜矿原矿输送系统实施改造的必要性,阐述了ABB数字式直流调速装置和西门子PLC在原矿输送生产线控制系统中的应用。生产实践证明,该系统投运后稳定可靠,使输送能力有很大提高,获得了显著的经济效益。 相似文献
57.
工业控制网络的发展 总被引:3,自引:0,他引:3
赵新秋 《自动化与仪器仪表》2008,(4)
阐述了工业控制网络及其特点,简要介绍了目前国际上已经应用的几种主要的控制网络,最后对控制网络的发展趋势进行了展望。 相似文献
58.
A study of the ozonation of distillery and tomato wastewaters was carried out in a small bubble contactor in order to obtain kinetic data for scaling-up. Thus, several parameters, such as chemical oxygen demand (COD), 254 nm absorbance (A254) and organic carbon content (OC), were followed during ozonation at different experimental conditions.
For distillery wastewaters all parameters investigated have the highest decreases during the first minutes of ozonation, A254 showing the highest disappearance rates. Thus, during the first fifteen minutes of ozonation an important decrease of the 254 nm absorbance (? 75%) was observed. At further reaction times values of all parameters studied decrease slowly, eventually reaching a plateau value. During approximately the first two hours of reaction, dissolved ozone was never found, which suggested that fast or moderate gas-liquid reactions took place in the wastewaters. 相似文献
59.
《Displays》2023
As a comprehensive integration of many new-generation information technologies, the metaverse has become a research hotspot that has attracted much attention. As a part of the metaverse, the industrial metaverse is expected to break through the constraints of space and time and promote high-quality industrial development. The industrial metaverse is human-centric, so its quality of experience (QoE) is a key topic. As one of the enabling technologies of the industrial metaverse, Mixed Reality (MR) can seamlessly integrate virtual information with the physical world and is widely regarded as an important window to the industrial metaverse. In close integration with other enabling technologies, industrial MR applications can be seen as a path toward the realization of the industrial metaverse; thus, the optimization of industrial MR applications can effectively achieve the QoE enhancement of the industrial metaverse. Based on the analysis of existing research and the characteristics of industrial scenarios, consistency, authenticity, smoothness, and comfort are identified as the factors that influence the user experience (UX) of industrial MR applications. Specific optimization methods for industrial MR applications are proposed to improve the UX with regard to these four factors. To verify the effectiveness of the proposed methods, a QoE evaluation model of the industrial metaverse based on the fuzzy analytic hierarchy process (FAHP) is established. Moreover, an industrial metaverse prototype for longwall mining that incorporates the proposed methods is developed and its QoE is evaluated. The results show that the proposed optimization methods for industrial MR applications significantly enhance the QoE in the industrial metaverse, and can provide better services for users in industrial systems, thus better serving these systems. 相似文献
60.
Recently, the rapid development of digital twin (DT) technology has been regarded significant in Cyber-physical systems (CPS) promotion. Scholars are focusing on the theoretical architecture and implementing applications, in order to establish a high-fidelity, dynamic, and full-lifecycle DT model and achieve a deep fusion of real and virtual. As a typical complex system with multi-disciplines, multi-physics, and multi-domain characteristics, industrial robot (IR) involves various processes and elements from the two other levels of the system: components and production lines. Their complex relationships lead to a huge challenge to build a comprehensive DT model. Current researchers usually concentrates on single-layer services because of limited construction methodology, which results in enormous isolated models, and leads to low reusable system blocks, finite scalability, and high costs of design, adjustment, upgrade, and maintenance. To address these issues, a standardized methodology and a hierarchical, modular, and generic architecture are proposed to depict comprehensive and variable industrial robot digital twin (IRDT). Firstly, the ontology information model is presented by analyzing variable factors systematically. Then, model-based system engineering (MBSE) based methodology is introduced, including construction process and variants management. After modeling process of three levels (problem domain, solution main, and implementation domain) and four viewpoints (requirement, structure, behavior, and parameter), a generic architecture of IRDT is constructed and a feature-based variants management method is described. Besides, a six-axis IRDTS is implemented to illustrate the mapping of logical architecture and physical system as a multi-level elements and processes representation example. And the steps of numerical evaluations consist of system delay and derivation. Finally, results show the effectiveness and the potential of the proposed theoretical methodology for constructing IRDTS and other industrial applications. 相似文献