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101.
102.
This letter extends a low-density parity-check code construction using maximum-length linear congruential sequences by Prabhakar and Narayanan. The corresponding bipartite graphs of their construction were guaranteed to have a girth larger than four by a sufficient condition. However, their sufficient condition was limited to regular codes and data-node degree equal to three. The extension in this letter allows arbitrary data-node degrees and is applicable to irregular codes. Further, simpler sufficient conditions are derived and larger girths are addressed. 相似文献
103.
Young Sil Jeon Jing Lei Ji-Heung Kim 《Journal of Industrial and Engineering Chemistry》2008,14(6):726-731
This study examined the removal of some basic dyes, such as Methylene Blue, Malachite Green and Methyl Orange, using alginate or alginate/polyaspartate composite gel beads. The adsorption of dyes from aqueous solutions at 25 °C was examined using a batch sorption technique. The effects of CaCl2 and the dye concentration on the adsorption were examined. Type-S adsorption isotherms were obtained, which is characteristic of a weak solute–solid interaction. The ionic interaction between the dye molecule and gel matrix appears to be responsible for the efficient adsorption of cationic dyes in this system. These results suggest that an alginate/polyaspartate gel can be used as an effective sorbent for water pollutants such as dyes, and the immobilization of these organic contaminants in the hydrogels from wastewater can solve one of the most important environmental problems in the related industry. 相似文献
104.
105.
Jing Wang 《Materials Letters》2007,61(3):917-920
As a powerful method for the study of mechanical properties at micro-/nanoscale, nanoindentation was applied to measure the hardness and elastic modulus of bacteria-templated metallic nanomaterials for the first time. Based on the morphological characterization by Atomic Force Microscopy (AFM) and Transmission Electron Microscopy (TEM), nanoindentation testing results showed that after coating with nickel via electroless chemical plating, the elastic modulus and hardness of bacterial cells were increased about 17 times and 50 times, respectively, indicating a great improvement in mechanical properties. This study would lay a forceful mechanical foundation for a better and general understanding of this kind of biotemplated metallic nanomaterials, which showed potential applications in nanoelectronics, nanomagnetism and nanomechanics. 相似文献
106.
FloorControl是在大型网络实时交互平台下对共享资源进行控制管理的一项技术。FloorControl的概念分为机制和策略两个部分,协议属于机制,而策略则是具体的控制办法。本文着重介绍了在共享应用中使用FloorControl的技术要点,分析了目前常用的FloorControl协议,并给出了若干具体的FloorControl策略,这些策略的共同作用结果是具有公平、灵活和协同性。 相似文献
107.
以双柳矿选煤厂为例,对Quantum系列PLC集中控制系统进行了分析,重点介绍了该系统的技术特点、工作原理和结构组成,并提出了日常使用维护的相应措施。 相似文献
108.
Shu‐Li Sun Jing Ma Nan Lv 《International Journal of Adaptive Control and Signal Processing》2008,22(10):932-948
Based on the optimal fusion estimation algorithm weighted by scalars in the linear minimum variance sense, a distributed optimal fusion Kalman filter weighted by scalars is presented for discrete‐time stochastic singular systems with multiple sensors and correlated noises. A cross‐covariance matrix of filtering errors between any two sensors is derived. When the noise statistical information is unknown, a distributed identification approach is presented based on correlation functions and the weighted average method. Further, a distributed self‐tuning fusion filter is given, which includes two stage fusions where the first‐stage fusion is used to identify the noise covariance and the second‐stage fusion is used to obtain the fusion state filter. A simulation verifies the effectiveness of the proposed algorithm. Copyright © 2008 John Wiley & Sons, Ltd. 相似文献
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