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11.
For oil sand extractions with microemulsions it is important to disperse large quantities of light hydrocarbons in an aqueous medium. Fundamental studies on the properties of 2-butoxyethanol (BE) and diethylmethylamine (Et2McN) in water suggest that these two liquids could be more effective cosurfactants than the usual alcohols used for this purpose. The phase diagrams of microemulsions using BE and Et2MeN as cosurfactants, combined with typical ionic and non-ionic surfactants and typical aliphatic and aromatic hydrocarbons, were therefore investigated and compared with microemulsions based on n-butanol. Although the phase diagrams depend significantly on the nature of the surfactant and of the oil, the monophasic region generally increases with the cosurfactant in the order n-butanol < Et2McN < BE. With the active mixture BE-cetyltrimethylammonium bromide, temperature has little effect on the phase diagram and NaCl generally destabilizes the microemulsion. 相似文献
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针对弧光保护系统的实际需要,设计了一种基于SPI的双机通信系统。简要阐述了该系统的设计思路,并给出了具体的实现方法。实验表明,采用该方法能够满足实际工程中的需求,对于其他SPI的应用也有很好的借鉴价值。 相似文献
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Lili Wang Yan Tu Li Chen Panpan Zhang Kees Teunissen Ingrid Heynderickx 《Journal of the Society for Information Display》2010,18(6):405-414
Abstract— One of the most annoying distortions in (auto)stereoscopic displays is probably cross‐talk, visible as double edges, which is mainly caused by an imperfect separation of left‐ and right‐eye images. For different types of three‐dimensional (3‐D) displays, cross‐talk is caused by different origins, which could result in different levels of perceived image distortion. To evaluate the influence of (auto)stereoscopic display technology on cross‐talk perception, optical measurements and subjective assessments were performed with three different types of 3‐D displays. It is shown with natural still images that the 3‐D display technology with the lowest luminance and contrast level tolerates the highest level of cross‐talk, while still maintaining an acceptable image‐quality level. 相似文献
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In this paper, we present a general framework, using a systems science approach, for developing a decision support system (DSS) for fisheries management. Decision support systems are quantitative tools for managers to evaluate outcomes of their policies prior to implementation. Our fishery model considers multiple stocks and fisheries simultaneously in balancing catch among targeted and protected fish abundances. Since in the Northeastern US multispecies fishery the distribution of abundance, catch-per-unit-effort and bycatch vary geographically, we focus on a spatial management approach to address their spatial variability. The core component of this DSS applies operations research techniques of simulation and optimization to determine the optimal inter-annual and intra-annual fishing plans in terms of fishing efforts in each sub-area and the time period. The result is the recommended amount to catch from each fish species at each sub-area at any time period so that while management objectives for sustainability of fish stocks are satisfied, the value of landings is maximized. The graphical user interface of the proposed DSS helps users to define inputs, to set constraints and sub-area boundaries, and to visualize the outcomes. 相似文献
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面向嵌入式零代码基础使用者和低成本开发者,搭建了一个基于STM32的软硬件一体化编程的流程图化的嵌入式系统开发平台.该平台采用STM32作为硬件载体,用QT跨平台C++图形用户界面搭建简单易懂的流程图操作界面.硬件框图界面能驱动嵌入式设备,用编译软件封装功能模块放置功能编辑盒,通过命令行调用编译器,调用外部烧录软件完成下载,代码查看器可直观监视编译全过程.测试结果表明,该平台可方便、快捷解决编程问题. 相似文献
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A normalized measure is established to provide the quantitative information about the degree of observability for the discrete-time, stochastically autonomous system. This measure is based on the generalized information theoretic quantities (generalized entropy, mutual information) of the system state and the observations, where the system state can be a discrete or a continuous random vector. Some important properties are presented. For the linear case, the explicit formula for the degree of observability is derived, and the equivalence between the proposed measure and the traditional rank condition is proved. The curves for the degree of observability are depicted in a simple example. 相似文献
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造纸过程水分智能控制 总被引:3,自引:0,他引:3
针对造纸过程的复杂性、工艺特点及要求,本文对造纸过程的水分控制,提出模糊控制和专家系统结合的智能控制方法。实践证明该控制器满足了造纸过程对水分的工艺要求,且具有良好的鲁棒性。 相似文献
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