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1.
Aromatic characterization is a key element of enhancing one’s knowledge of wine. While several studies have investigated the importance of wine expertise in the ability to perform odor-related sensory tasks, little attention has been paid to the influence of expertise on the semantic categorization of wine odors. To bridge this gap, this study aimed to explore the influence of a subject’s expertise on the semantic representation of wine odors by means of a free sorting task. For this purpose, 156 subjects were recruited. Their level of expertise was measured using a questionnaire and the data analysis revealed four clusters of subjects with a gradual level of expertise. Subjects also performed a sorting task on 96 odor terms. From the number and the size of odor groups formed, as well as the additive tree representation and the consensus partition between the terms for each expertise level, we observed that all subjects, regardless of their experience, had largely the same semantic categorization of wine-odor attributes, which was mainly shaped by the sources of the odorants. It appeared that level of wine expertise played a minor role in creating the semantic representation of wine odors, affecting mainly the knowledge of specialized terms.  相似文献   
2.
单汽泡沸腾过程数值模拟的研究   总被引:1,自引:0,他引:1  
《石油化工》2015,44(11):1295
利用Comsol Multiphysics软件中的Level Set方法对单汽泡沸腾过程进行了模拟,建立了微细结构网格,给出了边界条件,求解了质量、动量、能量和Level Set方程,得到了正确的模拟结果。分析了单汽泡沸腾过程中相含率、压力场、速度场和温度场随时间的变化规律;考察了接触角和壁面效应对汽泡脱离直径和汽泡生长周期的影响。模拟结果表明,当接触角小于12°时,汽泡脱离直径维持不变;当接触角大于12°时,接触角越大,汽泡脱离直径越大。汽泡生长周期随接触角的增大而延长。当加热装置的直径小于汽泡脱离直径时,汽泡受壁面效应的影响不易脱离;当加热装置的直径大于汽泡脱离直径时,汽泡脱离直径不随加热装置直径的增大而变化;汽泡生长周期随加热装置直径的增大而缩短。  相似文献   
3.
In the era of digitalization, there are many emerging technologies, such as the Internet of Things (IoT), Digital Twin (DT), Cloud Computing and Artificial Intelligence (AI), which are quickly developped and used in product design and development. Among those technologies, DT is one promising technology which has been widely used in different industries, especially manufacturing, to monitor the performance, optimize the progresses, simulate the results and predict the potential errors. DT also plays various roles within the whole product lifecycle from design, manufacturing, delivery, use and end-of-life. With the growing demands of individualized products and implementation of Industry 4.0, DT can provide an effective solution for future product design, development and innovation. This paper aims to figure out the current states of DT research focusing on product design and development through summarizing typical industrial cases. Challenges and potential applications of DT in product design and development are also discussed to inspire future studies.  相似文献   
4.
解读现代建筑中的廊空间   总被引:4,自引:0,他引:4  
王彦杰  仲德崑 《华中建筑》2004,22(2):42-44,51
廊是比较传统的建筑物或建筑元素,但依日常用于各种类型的现代建筑中,成为建筑的亮点。从概念出发,对具体实例进行解析,总结出廊空间在现代建筑中的作用与设计手法。  相似文献   
5.
In order to calculate the burnt mass fraction of complex three‐dimensional (3D) propellant grains to meet the requirements of interior ballistic modelling; the level set method is introduced to emulate and calculate the burning surface area of partially cut 7‐perforated propellant. The surface evolution and simulation of a 3D grain of partially cut 7‐perforated propellant are divided into two parts: the grain configuration initialization and the level set calculation of the propellant regression process. Parallel layer burning is assumed so that the burning surface regresses layer by layer in a direction normal to the surface until the grain is burnt completely. As the burnt mass fraction increases, the remaining propellant volume decreases gradually. The level set method easily simulates the slivering process for complex grain geometries. In this way, the burnt mass fraction of partially cut 7‐perforated propellant grain can be calculated by the level set method for the entire combustion process. Results show that the level set method is suitable to capture the burning surface for each burning step and its related parameters, such as the burning area, the remaining propellant volume and burnt mass fraction. More importantly, the level set method gives a possible solution to the coupling of grain combustion with the internal fluid simulation by the pressure and velocity. It is impossible for geometry‐based methods to integrate the internal fluid parameters in an interior ballistic model. Also, the level set method will benefit substantially the grain design and lead to improved internal ballistic performance.  相似文献   
6.
出于生产安全及经济安全的目的,根据标准规范的要求,需为储油罐设置液位保护或报警,满足储罐收发油作业安全平稳进行,实现这一目标的关键在于准确设定储罐的高、低液位报警高度。为设计储罐的储存液位,系统整理了固定顶罐和浮顶罐高、低液位的计算方法,利用积分和迭代算法详细论证了卧式罐单位时间内最大进/出液折算高度,进而计算卧式罐设计储存液位高度值,并以某油库现场卧式罐为例将计算值与现场设定参数进行比较。结果表明,计算所得卧式罐高、低液位报警高度与现场实际运行情况相符。  相似文献   
7.
文章针对最新版EMV Level 1标准,对PCD的EMV Level 1 Analog test认证的检测环境及检测项目进行总结,对实际测试中可能遇到的问题进行分析,总结出其技术难点。针对这些难点提出PCD设计中需要重点关注的方面以及设计技巧,进一步给出调试中使用怎样的方法达到系统的最优配置,成功通过EMV Level1 Analog test的检测。  相似文献   
8.
In this paper, a fuzzy controller is designed based on parallel distributed compensation (PDC) method and it is implemented in an experimental tank level control system. Firstly, a mathematical model of the system is obtained experimentally. An important feature of the plant is its nonlinearity. To control the level of water in the tank over the whole range, the nonlinear model of the system is linearized around three different operating points. Then, three PI controllers are designed for the operating points, using Skogestad's method. By using the PDC method, an overall fuzzy controller is designed by the fuzzy blending of the three PI-controllers. To evaluate the practical performance of the PDC-based fuzzy controller, the control system is implemented in the experimental system. The evaluation criteria considered are step response and disturbance rejection. The comparison results showed the superiority of the PDC-controller over the classical PI-controller.  相似文献   
9.
Risk assessments for bromate (BrO3-) in drinking water are based on linear extrapolation from the total incidence of tumors in male rats. The only genotoxic effects that might result from carcinogenic doses of BrO3- in vivo are the formation of 8-oxodeoxyguanosine (8-oxoG) in deoxyribonucleic acid (DNA) and the production of micronuclei. The mutations in tumors are consistent with the 8-oxoG adduct, and both effects are nonlinear with respect to dose. Treatment of rats with BrO3- resulted in bromination of protein tyrosines. The accumulation of these proteins in the kidney appeared to contribute to kidney cancer in male, but not female, rats. BrO3- increased the rate of apoptosis (programmed cell death) in the kidneys of rats of both sexes, an effect associated with increasing expression of antiapoptotic genes and proteins. Consequently, suppression of apoptosis is a likely mechanism for BrO3- induced kidney cancer. More limited data suggest nongenotoxic modes of action for thyroid tumors and mesotheliomas. If these data are confirmed, linear extrapolation of risk to low doses is inappropriate.  相似文献   
10.
As the size and complexity of Cloud systems increase, the manual management of these solutions becomes a challenging issue as more personnel, resources and expertise are needed. Service Level Agreement (SLA)-aware autonomic cloud solutions enable managing large scale infrastructure management meanwhile supporting multiple dynamic requirement from users. This paper contributes to these topics by the introduction of Cloudcompaas, a SLA-aware PaaS Cloud platform that manages the complete resource lifecycle. This platform features an extension of the SLA specification WS-Agreement, tailored to the specific needs of Cloud Computing. In particular, Cloudcompaas enables Cloud providers with a generic SLA model to deal with higher-level metrics, closer to end-user perception, and with flexible composition of the requirements of multiple actors in the computational scene. Moreover, Cloudcompaas provides a framework for general Cloud computing applications that could be dynamically adapted to correct the QoS violations by using the elasticity features of Cloud infrastructures. The effectiveness of this solution is demonstrated in this paper through a simulation that considers several realistic workload profiles, where Cloudcompaas achieves minimum cost and maximum efficiency, under highly heterogeneous utilization patterns.  相似文献   
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