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无线传感器网络覆盖问题中的目标最优运动模式臧传治,于海斌,梁韡,白洁音摘 要:研究无线传感器网络中的覆盖问题,这对传感器网络的节能,性能优化以及部署策略等问题具有十分重要的意义.相对已有的传感器模型和Exposure模型,给出更合理,更符合实际的模型,而且新模型便于分析计算.给定目标的起点,分析出使其具有最大值和最小Exposure值的运动方向;给定目标的速率和运行时间,分析出使其Ex-posure值最大的运动模式.对Exposure的分析简化了对覆盖问题的分析工作.仿真结果验证了理论分析的正确性.关键词:传感器网络;覆盖;Exposure;......
, the high heat-resistance was usually obtained at the cost of thermal stability loss. The main factors were surface oxidation and microstructural changes during long-term high temperature exposure...]. Materials Park (OH): ASM International, 1994: 431-434. [3] GUAN Shao-xuan, KANG Qiang, WANG Qing-jiang, LIU Yu-yin, LI Dong. Influence of long-term thermal exposure on the tensile properties of a high......
Sun1,Yi-Zhou Zhou11. Institute of Metal Research ,Chinese Academy of Sciences2. Shenyang University of Technology摘 要:The effect of long-term thermal exposure... and transmission electron microscopy, and the phase transformation of the alloy during long-term thermal exposure was analyzed by X-ray diffraction patterns and differential thermal analysis. Results showed......
oxidation of methane(CPOM),Ni/CeO2-ZrO2-Al2O3 displayed the highest activity,which resulted from its largest BET area and best NiO dispersion.Furthermore,Ni/CeO2-ZrO2-Al2O3 maintained a long-time......
RHEOLOGICAL BEHAVIOUR FOR AN ANHYDRITE SPECIMEN AND DETERMINATION OF ITS LONG TIME STRENGTH李宏摘 要:<正> Based on the method of torsional creep... is more than another value , all the three stages of a creep curve,i.e. primary, steady -state and accelerated are exhibited. The long-time strength of the anhydrite specimen is acquired; it is 2.77......
largest BET area and best NiO dispersion. Furthermore, Ni/CeO2-ZrO2-Al2O3 maintained a long-time stability in CPOM, which was attributed to its best coking resistance among all the prepared catalysts......
affects the mechanical properties of the forging significantly. When the alloy is exposed at 125 ℃ or lower, the strength will increase and then keep stable for a long time. When the thermal exposure...): 73-77. [3] 张 坤, 戴圣龙, 黄 敏, 颜鸣皋. 长时间热暴露对Al-Cu-Mg-Ag合金微观组织的影响[J]. 材料工程, 2007, 11: 15-19.ZHANG Kun, DAI Sheng-long, HUANG Min, YAN Ming-gao. Effect of long time thermal exposure on microstructures of Al......
by the precipitation of M23C6 carbide and intermetallic Laves phase. DL-EPR test is unsuitable to evaluate the IGC susceptibility of B316 LX with long-time sensitization, because more carbides and intermetallic phases......
金属蠕变律及蠕变行为研究 屠勇1,孙亚芳2,孙训方2,金尧2,刘洪杰1,邓勇1 (1.东方锅炉厂材料研究所,自贡 643011;2.西南交通大学力学系,成都 610031) 摘要:蠕变过程中,材料内部状态的不断演化,使得材料的蠕变行为发生改变.本文提出考虑损伤和硬化影响的蠕变律.利用该蠕变律讨论了12Cr1MoV钢蠕变行为.分析结果表明,c在蠕变过程中始终变化,第二阶段仅仅是c相对稳定的阶段,其相对稳定程度和持续范围与载荷大小有关.在相同寿命分数下,不同应力水平引起的硬化状态也不相同. 关键词:蠕变; 蠕变律; 损伤; 硬化; 蠕变速率; [全文内容正在添加中] ......
农用棚膜人工加速老化试验与大气曝露试验相关性探讨 苗翠霞1,郑慧琴1 (1.北京燕山石化树脂应用研究所,北京,102500) 摘要:介绍农膜大气曝露试验与人工加速老化的试验结果,寻求农膜老化性能的变化规律,并探讨农膜大气曝露与人工加速老化试验之间性能变化的相关性. 关键词:加速老化; 相关性; 变化规律; [全文内容正在添加中] ......
