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61.
为了提高滑坡灾害预报准确率,改善传统的滑坡监测和预报中存在的参数选取困难及模糊控制系统作为预报模型精确度不高的问题,首先采用山体结构稳定性分析法进行滑坡灾害参数的选取,得出降雨量、含水率、土压力及岩土表面位移增量作为预报参数的结论;其次将选取的参数作为模糊系统的输入,建立滑坡灾害发生概率模型,并引入优化的GD算法修正预报模型中的动态参数,使模糊控制模型具有自适应性;同时与未优化的模糊控制模型以及单独模糊控制模型进行仿真对比,仿真结果表明,该控制算法收敛速度快,具有很好的收敛性;最后将该模型在某滑坡重点灾区实验区进行实验测试,实验结果显示该模型具有较好的收敛性,且预报精度达到90%。 相似文献
62.
Wireless Networks - Key generation leveraging wireless channel reciprocity can establish secret keys from unauthenticated broadcast channels and thus protect the communication of wireless networks.... 相似文献
63.
64.
Multi-tag collision imposes a vital detrimental effect on reading performance of an RFID system. In order to ameliorate such collision problem and to improve the reading performance, this paper proposes an efficient tag identification algorithm termed as the Enhanced Adaptive Tree Slotted Aloha (EATSA). The key novelty of EATSA is to identify the tags using grouping strategy. Specifically, the whole tag set is divided into groups by a frame of size F. In cases multiple tags fall into a group, the tags of the group are recognized by the improved binary splitting (IBS) method whereas the rest tags are waiting in the pipeline. In addition, an early observation mechanism is introduced to update the frame size to an optimum value fitting the number of tags. Theoretical analysis and simulation results show that the system throughput of our proposed algorithm can reach as much as 0.46, outperforming the prior Aloha-based protocols. 相似文献
65.
Water Resources Management - Seeking cost-effective design of urban hydrological facilities and drainage systems is an important task for many city planners. However, such a process has always been... 相似文献
66.
Multimedia Tools and Applications - We present three stages of a novel backgrounds subtraction method in this paper: a new pixel-block based randomized arrangement is utilized to preprocess all the... 相似文献
67.
68.
Ab initio molecular-dynamics simulations have been used to investigate the liquid and amorphous Al94-xNi6Lax (x=3-9) alloys. Through calculating the pair distribution functions and partial coordination numbers, the structure and properties of these alloys are researched, which will help the design bulk metallic glass. The concentration of La atoms can affect the short-range order of Al94-xNi6Lax alloys, which is also studied in this calculation result. 相似文献
69.
Dr. Sónia Teixeira Dr. Miguel M. Santos Prof. Ricardo Ferraz Prof. Cristina Prudêncio Prof. Maria H. Fernandes Prof. João Costa-Rodrigues Dr. Luís C. Branco 《ChemMedChem》2019,14(20):1767-1770
Novel ionic liquids and organic salts based on mono- or dianionic zoledronate and protonated superbases, choline and n-alkylmethylimidazolium cations, were prepared and characterized by spectroscopic and thermal analyses. Most of the prepared salts display amorphous structures and very high solubility in water and saline solutions, especially the dianionic salts. Among the zoledronate-based ionic compounds, those containing choline [Ch] and methoxyethylmethylimidazolium [C3OMIM] cations appear to have significant cytotoxicity against human osteosarcoma cells (MG63) and low toxicity toward healthy skin fibroblast cells. Because osteosarcoma is a bone pathology characterized by an increase in bone turnover rate, the results presented herein may be a promising starting point for the development of new ionic pharmaceutical drugs against osteosarcoma. 相似文献
70.
Chen Gang Liss Klaus-Dieter Cao Peng Lu Xin Qu Xuanhui 《Metallurgical and Materials Transactions B》2019,50(1):429-437
Metallurgical and Materials Transactions B - Sintering behaviors of two types of powder compact, i.e., Ti/Al and TiH2/Al, under vacuum were studied using in situ neutron diffraction, in situ... 相似文献