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111.
112.
The purpose of this study was to evaluate the usability perception of seniors on video game use with different control devices. Twenty-four seniors participated in the study (12 women, 12 men, 69 years old in average) and eight children (8 years old in average). The setting included the use of two Kinect motion sensors, three computers, three projectors, three video cameras, two audio devices, the Angry Birds and Happy Sky videogames, one Xbox 360 console, a Nintendo Wii device and a Touchscreen configured so that participants could play the games in senior–child pairs. Data were collected according to user friendliness, experience and social interaction. This study suggests that video game control devices for seniors should be adapted to compensate for their function, sensor and cognitive limitations.  相似文献   
113.
We developed two radiation mapping algorithms that can handle different situations based on prior information of the search area. The algorithms were developed in the framework of model-driven measurement, where a world model was used to drive measurement collection, and measurements were used to update the world model.We developed and experimentally tested a robotic implementation of two Bayesian-based radiation mapping strategies in two dimensions, using a commercially available desktop mobile robot fitted with a CsI radiation sensor. Our approach for implementing the Bayesian radiation mapping algorithms was to drive the robot over each segment of the search area, in real time, according to the radiation counts collected by the sensor. Future research directions include extensions to three-dimensional mapping; exploring and characterizing the tradeoffs between time efficiency, map confidence level, and utilization of prior knowledge information; as well as the implementation of Bayesian statistics for the online update of the world model.  相似文献   
114.
首先讨论传统的设计方法在设计无线通信系统物理层基带部分时的弊端。然后展示一个具有可行性的设计流程,它基于使用信号处理工作系统(SPW)作为系统和硬件工程师的通用设计平台。  相似文献   
115.
Fabrication of uranium oxicarbide microspheres, a component of TRISO fuel particles for high temperature nuclear power systems, is based on the internal gelation of uranium salts in the presence of carbon black. In order to obtain a high quality product, carbon black should remain dispersed during all phases of the gelation process. In this study, the surface and structural properties of several commercial carbon black materials, and the use of dispersing agents was examined with the goal of finding optimal conditions for stabilizing submicron-sized carbon black dispersions. Traditional methods for stabilizing dispersions, based on the use of dispersing agents, failed to stabilize carbon dispersions against large pH variations, typical for the internal gelation process. An alternate dispersing method was proposed, based on using surface-modified carbons functionalized with strongly ionized surface groups (sodium sulfonate). With a proper choice of surface modifiers, these advanced carbons disperse easily to particles in the range of 0.15-0.20 μm and the dispersions remain stable during the conditions of internal gelation.  相似文献   
116.
Current capabilities of Large-Eddy Simulation (LES) in Eulerian–Lagrangian studies of dispersed flows are limited by the modeling of the Sub-Grid Scale (SGS) turbulence effects on particle dynamics. These effects should be taken into account in order to reproduce accurately the physics of particle dispersion since the LES cut-off filter removes both energy and flow structures from the turbulent flow field. In this paper, we examine the possibility of including explicitly SGS effects by incorporating ad hoc closure models in the Lagrangian equations of particle motion. Specifically, we consider candidate models based on fractal interpolation and approximate deconvolution techniques. Results show that, even when closure models are able to recover the fraction of SGS turbulent kinetic energy for the fluid velocity field (not resolved in LES), prediction of local segregation and, in turn, of near-wall accumulation may still be inaccurate. This failure indicates that reconstructing the correct amount of fluid and particle velocity fluctuations is not enough to reproduce the effect of SGS turbulence on particle near-wall accumulation.  相似文献   
117.
量测平台的复杂性和光学原理上的局限性制约着测量系统的应用,直到真空紫外光谱反射仪的出现,这种状况才得到改变。  相似文献   
118.

The need to leverage knowledge through data mining has driven enterprises in a demand for more data. However, there is a gap between the availability of data and the application of extracted knowledge for improving decision support. In fact, more data do not necessarily imply better predictive data-driven marketing models, since it is often the case that the problem domain requires a deeper characterization. Aiming at such characterization, we propose a framework drawn on three feature selection strategies, where the goal is to unveil novel features that can effectively increase the value of data by providing a richer characterization of the problem domain. Such strategies involve encompassing context (e.g., social and economic variables), evaluating past history, and disaggregate the main problem into smaller but interesting subproblems. The framework is evaluated through an empirical analysis for a real bank telemarketing application, with the results proving the benefits of such approach, as the area under the receiver operating characteristic curve increased with each stage, improving previous model in terms of predictive performance.

  相似文献   
119.
One continues the qualitative analysis started in Part I (F?ciu and Molinari in Acta Mech) concerning the thermomechanical characteristics of a steady, structured moving phase boundary in a shape memory alloy (SMA) by a quantitative investigation. The internal structure of these interphase layers is governed by a Maxwellian rate-type constitutive equation coupled or not with the Fourier heat conduction law. We consider as equilibrium stress–strain–temperature response function for the Maxwellian model an explicit piecewise linear thermoelastic relation for an SMA bar which can exist in the austenite phase A and in two variants of martensite M ±. Its thermal properties are built in agreement with experimental results on NiTi. This equilibrium relation has the atypical property that not only the derivative of the stress response function with respect to the strain changes its sign, but also the derivative with respect to the temperature. Considerable temperature variation is generated by impact-induced phase transformations due to the large amount of latent heat released (absorbed) inside the transition layer. One gets strong heating (cooling) across a compressive AM ? (expansive M ?A) propagating interphase layer. A significant lower (larger) temperature than that at the front and Hugoniot back state is obtained inside an impact-induced M +M ? (M ?M +) interphase layer. The experimental finding of this phenomenon of temperature undershoot (overshoot) could be a valuable indication for the existence of an interphase layer.  相似文献   
120.
Fault diagnosis of air conditioning systems based on qualitative bond graph   总被引:1,自引:0,他引:1  
The bond graph method represents a unified approach for modeling engineering systems. The main idea is that power transfer bonds the components of a system. The bond graph model is the same for both quantitative representation, in which parameters have numerical values, and qualitative approach, in which they are classified qualitatively. To infer the cause of faults using a qualitative method, a system of qualitative equations must be solved. However, the characteristics of qualitative operators require specific methods for solving systems of equations having qualitative variables. This paper proposes both a method for recursively solving the qualitative system of equations derived from bond graph, and a bond graph model of a direct-expansion, mechanical vapor–compression air conditioning system. Results from diagnosing two faults in a real air conditioning system are presented and discussed. Occasionally, more than one fault candidate is inferred for the same set of qualitative values derived from measurements. In these cases, additional information is required to localize the fault. Fault diagnosis is initiated by a fault detection mechanism which also classifies the quantitative measurements into qualitative values; the fault detection is not presented here.  相似文献   
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