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91.
覃德泽 《网络安全技术与应用》2012,(4):60-62
本文简述了对等网络的概念及分类,分析了结构化对等网络特性、存在问题和关键技术,指出结构化对等网络的发展前景。 相似文献
92.
Gary Gibson Xia Sheng Dick Henze Si‐Ty Lam Patricia Beck Yoocharn Jeon Zhang‐Lin Zhou Brad Benson Qin Liu Gregg Combs Tim Koch Kent Biggs 《Journal of the Society for Information Display》2012,20(10):552-558
Reflective displays are advantageous in applications requiring low power or daylight readability. However, there are no low‐cost reflective technologies capable of displaying bright colors. By employing photoluminescence to more efficiently use ambient light, we created a prototype display that provides bright, full color in a simple, low‐cost architecture. This prototype includes a novel electrokinetic shutter, a layer that incorporates patterned luminescent red, green, and blue sub‐pixel elements, and a novel optical out‐coupling scheme. The luminescent elements convert otherwise‐wasted portions of the incident spectrum to light in the desired color band, resulting in improved color saturation and lightness. This prototype provides a color gamut that is superior to competing reflective display technologies that utilize color filters in single‐layer side‐by‐side sub‐pixel architectures. The current prototype is capable of switching in <0.5 s; future displays based on an alternative electro‐optic shutter technology should achieve video rate operation. A transflective version of this technology has also been prototyped. The transflective version utilizes its backlight with a power efficiency that is at least three times that of a conventional liquid crystal display. These photoluminescence‐based technologies enable a host of applications ranging from low‐power mobile products and retail pricing signage to daylight readable signage for outdoor advertising segments. 相似文献
93.
Guozheng Qin Zhisheng Duan 《International Journal of Control, Automation and Systems》2012,10(3):651-658
In this paper, an output chattering attenuation scheme is proposed for two tracking controllers. The controllers have integral actions and are used to eliminate the steady-state tracking errors. By designing a compensator and reducing the discontinuous switching, the output chattering at the switching points can be attenuated significantly. Moreover, combining with the generalized Kalman-Yakubovich-Popov (KYP) lemma and the parameter-dependent Lyapunov function method, this problem can be characterized in terms of linear matrix inequality (LMI) formulation. Finally, the simulation results demonstrate the effectiveness of the proposed method. 相似文献
94.
Xin Fusheng Ding Wangwang Tao Qiying Tian Hanqing Chen Gang Qin Mingli Qu Xuanhui 《Metallurgical and Materials Transactions A》2022,53(4):1164-1175
Metallurgical and Materials Transactions A - In this work, we used hydride-dehydride Ti (HDH-Ti) powders (with the oxygen levels of 0.17 and 0.51 wt pct, respectively) combined with microstructural... 相似文献
95.
混凝土是巷道支护过程中的重要建筑材料,然而混凝土在巷道施工中常常出现质量问题,为了不影响正常生产,需要对其进行修补。地聚合物混凝土凝结时间快,早期强度高,界面结合能力强,耐高温性和抗冻性强,耐腐蚀性良好,具有用作修补材料的潜力。以粉煤灰和矿粉为原料,Na2SiO3溶液和NaOH为碱激发剂制备地聚合物胶砂,研究不同的碱激发剂模数(1.0、1.2、1.4)和掺量(10%、15%、20%)对不同龄期胶砂力学性能的影响。结果表明:当碱激发剂模数为1.2,碱掺量为15%时,胶砂强度达到最大值。设计正交试验,研究了不同水胶比(0.45、0.50、0.55)、粉煤灰掺量(30%、50%、70%)和砂率(30%、35%、40%)对不同龄期地聚合物混凝土的工作性能和力学性能的影响。结果表明:粉煤灰掺量对抗压强度影响最为显著,水胶比次之,而砂率对强度发展几乎没有影响。最优的配合比为水胶比为0.50,粉煤灰掺量为50%,砂率为35%。 相似文献
96.
采用“单颗”回摆法,在普通的德拜相机中,对重量只有0.003μg的超微量物质进行X射线相分析。 对方法的原理、衍射角的测量及计算、衍射斑点的数目、各个斑点的相对强度与ASTM卡片上同一物质各线条的相对强度间的关系等问题,进行了详细的分析和讨论。 举例说阴这种方法在鉴定稀土夹杂物上的应用,并验证所推导的公式的正确性。 相似文献
97.
聚氨酯防水涂料是当今最有效的柔性防水材料之一,介绍了聚氨酯防水涂料的发展状况,并对其市场前景进行了展望。 相似文献
98.
Medium-Term Hydro Generation Scheduling (MTHGS) with Chance Constrained Model (CCM) and Dynamic Control Model (DCM) 总被引:1,自引:0,他引:1
Jianzhong Zhou Mengfei Xie Zhongzhen He Hui Qin Liu Yuan 《Water Resources Management》2017,31(11):3543-3555
Medium-Term Hydro Generation Scheduling (MTHGS) plays an important role in the operation of hydropower systems. In the first place, this paper presents a Chance Constrained Model for solving the optimal MTHGS problem. The model recognizes the impact of inflow uncertainty and the constraints involving hydrologic parameters subjected to uncertainty are described as probabilistic statements. It aims at providing a more practical technique compared to the traditional deterministic approaches used for MTHGS. The stochastic inflow is expressed as a simple discrete-time Markov chain and Stochastic Dynamic Programming is adopted to solve the model. Then in order to use the information of long-term inflow forecast to improve dispatching decisions, a Dynamic Control Model is developed. Short-term forecast results of the current period and long-term forecast results of the remaining period are treated as inputs of the model. Finally, the two methods are applied to MTHGS of Xiluodu hydro plant in China. The results are compared to those obtained from Deterministic Dynamic Programming with hindsight and advantages and disadvantages of the two methods are analyzed. 相似文献
99.
A set of Co promoted 10% Mo/Al2O3 samples have been characterized by means of Raman spectroscopy under ambient as well as in situ dehydrated conditions. Under ambient conditions, the degree of the polymerization of surface molybdenum oxide species decreases with increasing Co loading. Under dehydrated conditions, the polymeric molybdenum oxide species is absent with the addition of only 0.2% Co. At low Co loadings (2%), before the formation of CoMoO4 compound, the spectral features are very similar under ambient conditions. Dehydration causes the upward shift of the Mo=O symmetric stretching mode. A broad band around 920–930 cm–1 was thus observed. This band has been suggested to be associated with the Co-Mo interaction species. In contrast to crystalline CoMoO4, this species shows a reversibility on H2 reduction-O2 reoxidation treatments. From the results obtained, it is proposed that cobalt oxide interacts with the most polymerized molybdenum oxide species to form Co-Mo interaction species and/or crystalline CoMoO4; therefore, the amount of the surface molybdenum oxide species decreases with a change in the molecular structure as a function of the Co concentration. 相似文献
100.
回顾了2005年我国烧碱的生产与市场消费情况,分析了2006年国内烧碱市场形势,对“十一五”期间我国烧碱市场总体趋势进行了展望。 相似文献