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1.
In this paper, a novel decentralized adaptive neural control scheme is proposed for a class of interconnected large‐scale uncertain nonlinear time‐delay systems with input saturation. Radial basis function (RBF) neural networks (NNs) are used to tackle unknown nonlinear functions. Then, the decentralized adaptive NN tracking controller is constructed by combining Lyapunov–Krasovskii functions and the dynamic surface control (DSC) technique, along with the minimal‐learning‐parameters (MLP) algorithm. The stability analysis subject to the effect of input saturation constraints are conducted with the help of an auxiliary design system based on the Lyapunov–Krasovskii method. The proposed controller guarantees uniform ultimate boundedness (UUB) of all of the signals in the closed‐loop large‐scale system, while the tracking errors converge to a small neighborhood around the origin. An advantage of the proposed control scheme lies in the number of adaptive parameters of the whole system being reduced to one and in the solution of the three problems of “computational explosion,” “dimension curse,” and “controller singularity”. Finally, simulation results along with comparisons are presented to demonstrate the advantages, effectiveness, and performance of the proposed scheme.  相似文献   
2.
针对小样本、多类煤矿顶板的状态检测问题,提出了基于支持向量机集成的算法。采用深度优先搜索对支持向量机集成参数进行优化,并结合煤矿顶板敲击声信号的人耳听觉功率谱特征,对煤矿顶板中浮石、剥层等现象进行分类识别。实验表明,该算法能够对多类顶板状态进行有效分类,且识别率较高,能够作为安全开采的保障手段。  相似文献   
3.
基于智能对象的知识处理方法在专家系统中的应用研究   总被引:2,自引:1,他引:2  
在分析传统的基于被动对象的知识系统基础上,提出了一种基于智能对象的知识处理方法,并对基于智能对象的知识表示、存储及推理方法进行了较深入的研究。最后通过实例说明了该方法的有效性。  相似文献   
4.
热反射隔热涂料这一新型功能性涂料已在易挥发油品储罐及管道外表面成功地广泛使用,取得了降温减压、安全增效、节能节水的良好效果。介绍了此涂料的分类和主要技术指标:“隔热温差”不小于10℃;“隔热温差衰减(白色)”不大于12℃。“耐人工气候老化性”指标中“粉化/级”不大于1;“变色”(白色和浅色)/级不大于2;“太阳反射比(白色)”不小于0.81;“半球发射率”不小于0.83。涂料指标达到“太阳热反射比”不小于0.90(全波区);“半球发射率”不小于0.85“太阳热反射比”不小于0.90(全波区);“半球发射率”不小于0.85;罐体表面平均降温10~20℃;罐体介质温度降低约5~10℃。  相似文献   
5.
6.
放射性同位素衰变能发电机制的研究与探索   总被引:6,自引:0,他引:6  
王铁山  张保国 《核技术》1994,17(9):548-551
报道了国际上有关放射性同位素电池研究的最新动态。首次提出了利用β粒子的电磁辐射实现由核衰变能向电能直接转换的基本设想,并制定了具体的与β伏特效应相结合的技术路线。以期在实验上获得空前的能量转化率,在核衰变能发电机制研究领域取得突破性进展,同时为核废物的再利用探索新途径。研究结果表明对90Sr-90Yβ源理论上可达到62%的能量转换率极限,实验能量转换率可望达到27%。  相似文献   
7.
基于相似原理的摩擦材料1:5缩比台架及其可比性分析   总被引:1,自引:0,他引:1  
因试验设备结构、功能不同,导致车用摩擦材料摩擦磨损性能的小样试验结果与台架试验相差较大。为提高小样试验与台架试验的可比性,依据相似原理,并参照现有JFl22型轻轿车1:1惯性台架试验机的参数,研制了JFl22SB型摩擦材料1:5缩比台架摩擦试验机,用于轿车盘式制动器摩擦衬片的缩比试验。介绍了1:5缩比台架摩擦试验机的设计准则、缩比比例、主要参数和结构,并采用同一个试验方法标准SAEJ2681,与1:1台架进行了对比试验,结果表明:二者的试验数据具有良好的一致性和可比性。  相似文献   
8.
In this paper, an innovative framework labeled as cooperative cognitive maritime big data systems (CCMBDSs) on the sea is developed to provide opportunistic channel access and secure communication. A two-phase frame structure is applied to let Secondary users (SUs) entirely utilize the transmission opportunities for a portion of time as the reward by cooperation with Primary users (PUs). Amplify-and-forward (AF) relaying mode is exploited in SU nodes, and Backward induction method based Stackelberg game is employed to achieve optimal determination of SU, power consumption and time portion of cooperation both for non-secure communication scenario and secure communication. Specifically, a jammer-based secure communications scheme is developed to maximize the secure utility of PU, to confront of the situation that the eavesdropper could overheard the signals from SU i and the jammer. Close-form solutions for the best access time portion as well as the power for SU i and jammer are derived to realize the Nash Equilibrium. Simulation results validate the effectiveness of our proposed strategy.  相似文献   
9.
Structured surfaces have attracted wide attention because of their great potential in directional transport, liquid collection or separation, microfluidics, etc. However, it remains a big challenge to design a surface that can distinguish various liquids, utilize their inherent properties to control their transportation, and realize functional applications. Herein, it is presented an asymmetric soft-structure functional surface (ASFS) with arrayed curvature units that can make the Laplace pressure as a driving force to determine the preferential spreading direction and show abundant transport behaviors for liquids with different surface tensions. With good deformability, the proposed ASFS can directionally transport liquids along complex terrains, e.g., 1D-tilted, 2D-curved, and 3D-helical trajectories. It is also demonstrated that the ASFS can achieve synchronous or asynchronous liquid mixing by choosing appropriate liquids. Moreover, the intelligent response ability allows the ASFS to be a portable contact angle discriminator. This study proposes a new strategy to manipulate liquids via their intrinsic properties and opens new avenues for application-oriented liquid operation surfaces.  相似文献   
10.
To study the role of color in expectations of drug effects, 80 Chinese participants (40 females and 40 males) were asked to classify each of seven single colored capsules and six differently colored two‐piece capsules into one of four classifications of drug effects. The results from the Chinese sample were also compared with that from four other cultural groups studied elsewhere. The Chi‐square test results showed that all seven single colored capsules yielded non‐chance distributions in classifications of drug effects, with six showing specific effects; and that five two‐colored capsules had non‐chance distributions, with four significantly associated with specific effects. Notable gender differences were observed in the expectations of drug effects. While the cross‐group comparison revealed consistent red‐stimulant and blue‐depressant associations across the five cultural groups, disagreements existed for other colors among the groups. The findings emphasized the importance of color in drug design and administration in support of drug differentiation, medication adherence, and drug efficacy, and suggest gender and cultural implications on the basis of color to achieve better drug effects. © 2016 Wiley Periodicals, Inc. Col Res Appl, 42, 124–130, 2017  相似文献   
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