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101.
为解决数字家庭中设备间媒体共享的问题,研究UPnP协议和UPnP AV架构,设计实现基于嵌入式智能终端的媒体共享系统。针对智能手机、平板电脑的便携特性,单独实现控制点功能,支持“推播”模式,支持智能移动设备单独做控制点的操作逻辑。核心功能模块采用native开发,上层采用Java进行界面控制,已在Android设备上成功部署。测试结果表明,该系统可以很好地实现局域网内的媒体资源共享,提升用户娱乐体验。 相似文献
102.
多孔介质内部热质传递的等效耦合扩散模型的推导及其应用 总被引:1,自引:2,他引:1
基于Whitaker的体积平均方程,在不附加任何新的假设的基础上,对多孔介质内部热质传递的等效耦合扩散模型进行推导,得出了多孔介质内部热质传递的等效耦合扩散模型。并应用该模型对瓷质砖体干燥过程进行了数值模拟,模拟结果与实验结果十分吻合。 相似文献
103.
本文对碳纤维增强铸型尼龙(CF/MC 尼龙)复合材料在不同吸湿介质中的吸湿行为进行了研究。结果表明,对于纤维体积分数为10%的碳纤维增强铸型尼龙复合材料(10%CF/MC尼龙复合材料),随着吸湿介质的PH值减小,它的吸湿率增大。同时,经过吸湿后,10%CF/MC尼龙复合材料的弯曲强度有明显的下降。随着吸湿介质的PH值减小,试样的弯曲强度下降。使用环境扫描电子显微镜观察在10%HCl溶液中吸湿的试样的剪切断口形貌,得到的结果与吸湿实验的结果一致。 相似文献
104.
福建三明水泥厂矿渣和熟料易磨性不同,制约了 2.2 m×6.5m闭路水泥磨系统的产质量,导致产量低仅12 t/h;矿渣掺量低,仅7%;水泥强度低R28仅达47.0MPa。为此该厂增加了2台 2.2m×7.5m开流磨单独粉磨矿渣,实现熟料矿渣分别粉磨工艺。同时对 2_2m×6.5m矿渣磨进行结构改造和工艺操作参数调整。这样二套粉磨系统可根据熟料和矿渣的不同粉磨特性分别进行操作控制,工厂实现了高产高质,高矿渣掺量(达15%)和低成本生产。 相似文献
105.
Chen Kou Wei H. Ted Davis Eugenia A. Davis Joan Gordon 《Chemical Engineering Communications》1987,56(1):269-284
A capillary tube model was solved to investigate the influence of mass transfer coefficient, temperature, and front depth on the evaporation rate during the penetrating-front period of water-filled porous media dried in hot air. The results show that increasing the flow rate of the drying air is not so efficient as increasing the sample temperature. Due to attenuating diffusion rate, the rate of liquid front migration decreases with time. The calculations explain the falling rate period behavior of sandstone heated at 121°C. Trends depicted by the model may be useful for the design of heating conditions for drying processes. 相似文献
106.
Rotating disk electrode (RDE) and rotating ring-disk electrode (RRDE) measurements have been undertaken to study the behaviour of pure aluminum electrodes in alkaline media. The measurements did consist of linear sweep voltammetry from anodic to cathodic potentials on 4N, 5N or 5N5-aluminum samples in 4 M aqueous potassium hydroxide solution. In the potential range studied (−0.7 V versus NHE to −2.5 V versus NHE) the aluminum undergoes oxidation/dissolution into aluminates anions at high electrode potential while it yields strong hydrogen evolution at low potentials. Thanks to the RRDE technique, we show that hydrogen starts to evolve from the aluminum electrode even above the open circuit potential. Also, the oxidation state of superficial aluminum varies according to the electrode potential: whereas non-conducting aluminum oxides are present above the open-circuit potential hindering hydrogen evolution reaction (HER), they tend to disappear below the ocp, due to the strong hydrogen evolution, following the probable porous oxide layer blow up induced by the hydrogen bubbles formation. In consequence at very low potential, HER occurs on bare aluminum, HER kinetics being much faster than on oxide-covered aluminum. 相似文献
107.
韩忠明 《化学工业与工程技术》2004,25(3):27-29
介绍了国内外纯碱市场的状况、碱厂在海盐供应上存在的问题和淮安地区盐矿资源的情况 ,阐述了尽快实施卤水制碱项目的意义 ,简要说明了卤水除硝的技术方案 ,同时提出了推进项目实施进度的建议。 相似文献
108.
The inverse problem approach by conjugate gradient with adjoint equations is adapted to the context of a non-isothermal bioprocess, controlled by internal heat generation from microbial oxidation, as could be found in a composting reactor for instance, to determine the heat source from internal temperature measurements. The volumetric heat source is assumed proportional to the rate of consumption of a substrate by a biomass, as described by a Monod model. Computations are performed for Rayleigh numbers equal to 0.25 and 25, for a representative biochemical reaction under typical boundary conditions, for constant and temperature-dependent model parameters. The influence of noisy input data is also considered. It is found that good solutions can be obtained when heat release and diffusion occur over very different time scales. The variation of the model parameters with temperature must be taken into account, but single sensor solutions are possible at relatively small Rayleigh numbers when convection is present. 相似文献
109.
Benedikt Ley Corinna Ogonowski Jan Hess Tim Reichling Lin Wan Volker Wulf 《Behaviour & Information Technology》2014,33(8):815-828
Technological infrastructure at home is changing continuously and is becoming increasingly interconnected. Media devices, including the TV set, provide access to the Internet and offer manifold opportunities to consume media on demand. Additionally, personal devices, such as smartphones, also enable flexible consumption and sharing of media. Questions about how these technologies change the user's media usage and how these changes affect the social structure of a household, however, remain largely unanswered. In order to gain insight into the adoption of new technologies into daily routines, we explored these changes in respect of people's media usage in a qualitative long-term Living Lab study. We will present findings regarding personal routines, flexible integration of new devices into existing practices, influences on households as social systems and related issues in device access and collective use. We will highlight potentials and conflicts regarding device shifts and roles; restrictions in device access; social influences in the living room; and individual changes in media consumption. 相似文献
110.
A. V. Fedorov 《Combustion, Explosion, and Shock Waves》2004,40(1):17-31
A review is made of uptodate investigations in the field of physicomathematical modeling of mixing of solid particles with highvelocity gas flows arising under the action on shock waves, compression waves, and expansion waves on unstable dust deposits on the boundaries of channels or plates and in cavities, as well as on free clouds of particles. In particular, experiments in shock tubes with particles initially located in cavities and on surfaces are described. The experimental data presented in the form of distributions of particle concentrations at various points of space above the unstable layer, pressure distributions on the lower wall of the shock tube, etc., are used for verification of proposed mathematical models in regimes of single particles, interacting continua, and turbulent diffusion. An analysis of experimental and numerical data shows that the models considered sometimes allow adequate identification of the wave structure of motion of the mixture and the field of parameters inside and outside the layer. 相似文献