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1.
Healthcare delivery is evolving from disease-centered to patient-centered care delivery where patients are active participants in their healthcare delivery. This calls for more communication and collaboration among all healthcare actors. There is also an increasing demand for personalized healthcare systems that provide effective information management, facilitate communication and collaboration, and support applications to meet user requirements. To address these challenges, we need to advance the integration and interoperability of healthcare applications in a controlled manner. Drawing upon a conceptual model from a collaborative care case study, we identified a set of interoperability requirements and developed a Mashup based interoperability framework. Our framework allows patients and other healthcare actors to engage in collaborative processes through online applications facilitated by mashups. We then use proof-of-concept implementations to demonstrate how our framework is able to facilitate different types of interoperability. We believe that collaborative technologies such as mashups can implement process interoperability requirements to support collaborative care delivery, particularly for asynchronous care delivery.  相似文献   
2.
The final goal of this study was to manufacture an epoxy–glass leaf spring by microwave processing. The physical properties of the final part to be manufactured, in particular, the mechanical properties, were directly related at the repartition of microwave‐source heating during the treatment. The major problem in microwave processing, however, is the attenuation of the microwave source. Here, we propose a dielectric effect of attenuation inversion of the electromagnetic waves as a new method for the uniform treatment of epoxy–glass by microwave energy. This solution used the dielectric properties of the mold to control the microwave‐heat‐source attenuation into the composite to be treated. Many experiments were carried out to validate the proposed solution. The results show that the microwave‐source heating attenuation could controlled and inversed. We demonstrated the uniform treatment of epoxy–glass parts about 100 cm long by means of the compensation of microwave‐source attenuation. © 2013 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014 , 131, 39908.  相似文献   
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Convective drying of wastewater sludges and sawdust/sludge mixtures was studied. The first part of this work was an experimental study performed in a cross-flow convective dryer using 500 g of wet material extruded through a disk with circular dies of 12 mm. The results showed that the sawdust addition has a positive impact on the drying process from a mass ratio of 2/8, on a dry basis, with observed drying rates higher than the original sludge. The second part of this work consisted of developing a drying model in order to identify the internal diffusion coefficient and convective mass transfer coefficient from the experimental data. A comparison was made between fitted drying curves, well represented by the Newton's model, and the analytical solutions of the diffusion equation applied to a finite cylinder. Variations of dimensional characteristics, such as the volume and exchange surface of the sample bed, were obtained by X-ray tomography. This technique allowed us to confirm that shrinkage, which is an important phenomenon occurring during sludge and sawdust/sludge mixture drying, must be taken into account. The results showed that both the internal diffusion coefficient and convective mass transfer coefficient were affected by mixing and sawdust addition. The internal diffusion coefficient changed from 7.77 × 10?9 m2/s for the original sludge to 7.01 × 10?9 m2/s for the mixed sludge and then increased to 8.35 × 10?9 m2/s for the mixture of a mass ratio of 4/6. The convective mass transfer coefficient changed from 9.70 × 10?8 m/s for the original sludge to 8.67 × 10?8 m/s for the mixed sludge and then increased to 12.09 × 10?8 m/s for the mixture of a mass ratio of 4/6. These results confirmed that sawdust addition was beneficial to the sludge drying process as the mass transfer efficiency between the air and material increased. Reinforcing the texture of sludge by adding sawdust can increase the drying rate and decrease the drying time, and then the heat energy supply will be reduced significantly. The study also showed that neglecting shrinkage phenomenon resulted in an overestimation for the internal diffusion coefficient for the convective drying of sludges and sawdust/sludge mixtures.  相似文献   
5.
While capillary filling in channels of micrometers scale is experimentally verified to obey Washburn's law well, the speed of capillary filling in nanochannels is noticeably lower than described by Washburn's formula. This article reports the theoretical and experimental results on capillary filling in open-end and closed-end nanochannels. Nanochannels of 45 nm and 80 nm depth, 10 μm width, were etched in silicon and bonded to a glass cover. Experiments on filling of non-electrolytic liquid in silicon nanochannels were carried out. The filling processes were observed and recorded. To estimate the influence of electrokinetics, a mathematical model to calculate the electroviscous effect was established. This model shows that the contribution of the electroviscous effect in the reduction of filling speed is small. This result also agrees well with previous theoretical work on the electroviscous effect. That means that besides the electroviscous effect, there are other phenomena that contribute to the reduction of capillary filling speed in a nanochannel, such as air bubbles formation. Experimental investigation of capillary filling in open-end and closed-end nanochannels with different lengths was performed. The filling processes of ethanol and isopropanol and the behavior of the trapped air were recorded and evaluated. Analytical models based on the continuum assumption were used to evaluate the experimental data. We observed that the filling process consists of two stages. At the initial stage, experimental data agree well with the theoretical model, but with a higher apparent viscosity. In the final stage, condensation of the liquid phase and dissolution of the gas phase lead to total filling of the nanochannel. The observed phenomena are important for understanding the behavior of multiphase systems in nanochannels.  相似文献   
6.
Abstract—In this article, an improved deadbeat control algorithm suitable for digital signal processor-based circuit implementation is proposed. The control algorithm allows the derivation of a nearly sine wave output current with a fixed switching frequency of a current-controlled voltage source inverter. Two low-pass output filters configurations are considered in this study: a simple inductance filter and an LCL-filter. By taking advantage of prior knowledge of the state variables’ shape, the improved deadbeat control algorithm is based on a simple prediction model to derive the expected duty cycle needed to switch on and off the power switches. The control study of the grid-connected inverter with L and LCL output filters has been considered using a co-simulation approach with (Powersim Inc., Rockville, Maryland, USA) and MATLAB software (The MathWorks, Natick, Massachusetts, USA). The obtained results show the improvement of both shape quality and tracking accuracy of the output current quantified by low ripple content and a nearly unity power factor.  相似文献   
7.
We report on the experimental observation of bright photoluminescence emission at room temperature from single unstrained GaAs quantum dots (QDs). The linewidth of a single-QD ground-state emission (≈ 8.5 meV) is comparable to the ensemble inhomogeneous broadening (≈ 12.4 meV). At low temperature (T  ≤  40 K) photon correlation measurements under continuous wave excitation show nearly perfect single-photon emission from a single GaAs QD and reveal the single photon nature of the emitted light up to 77 K. The QD emission energies, homogeneous linewidths and the thermally activated behavior as a function of temperature are discussed.  相似文献   
8.
Lyes  Hamamache   《Ad hoc Networks》2008,6(2):168-194
The ad hoc networks are completely autonomous wireless networks where all the users are mobile. These networks do not work on any infrastructure and the mobiles communicate either directly or via other nodes of the network by establishing routes. These routes are prone to frequent ruptures because of nodes mobility. If the future movement of the mobile can be predicted in a precise way, the resources reservation can be made before be asked, which enables the network to provide a better QoS. In this aim, we propose a virtual dynamic topology, which on one hand, will organize the network as well as possible and decreases the impact of mobility, and on the other hand, is oriented user mobility prediction. Our prediction scheme uses the evidence theory of Dempster–Shafer in order to predict the future position of the mobile by basing itself on relevant criteria. These ones are related to mobility and network operation optimisation. The proposed scheme is flexible and can be extended to a general framework. To show the relevance of our scheme, we combine it with a routing protocol. Then, we implemented the prediction-oriented topology and the prediction scheme which performs on it. We implemented also a mobility prediction based routing protocol. Simulations are made according to a set of elaborate scenarios.  相似文献   
9.
Achieving competitiveness in nowadays manufacturing market goes through being cost and time-efficient as well as environmentally harmless. Reconfigurable manufacturing system (RMS) is a paradigm that is able to meet these challenges due to its scalability and integrability. In this paper, we aim to solve the multi-objective sustainable process plan generation problem in a reconfigurable environment. In addition to the total production cost and the completion time, we use the amount of greenhouse gases (GHG) emitted during the manufacturing process as a sustainability criterion. We propose an iterative multi-objective integer linear programming (I-MOILP) approach and its comparison with adapted versions of the two well-known evolutionary algorithms, respectively, the Archived Multi-Objective Simulated Annealing (AMOSA) and the Non-dominated Sorting Genetic Algorithm (NSGA-II). Moreover, we study the influence of the probabilities of genetic operators on the convergence of the adapted NSGA-II. To illustrate the applicability of the three approaches, an example is presented and obtained numerical results analysed.  相似文献   
10.
The main objective is studying the fundamental aspect, by means of drying kinetics and the application of forced convective drying of wastewater sludge with the determination of the optimum drying conditions. The drying system is composed of two units; small samples of 2.5 g are dried in the first unit and a bed of sludge weighing 250 g is dried in the second unit. The experiments are performed under air temperatures varying between 80°C and 200°C. The range of the air velocity and its humidity is 1–2 m/s and 0.005–0.05 kgwater/kgdry air, respectively. The experiments are performed for two different sludges: activated sludge (AS) and thermalized and digested sludge (TDS). Usually, three main drying phases are observed during drying of bed of sludge. These phases are reduced to only two for small samples. Determination of the influent parameters shows that the temperature of the drying air and sludge origin can profoundly influence the drying kinetic of the sludge. The exergy analysis of the two units of the drying system allows selecting 140°C, 2 m/s, and 0.05 kgwater/kgdry air as optimum drying conditions with an exergy efficiency reaching 90%.  相似文献   
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