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111.
针对基本遗传算法在机器人路径规划中存在收敛速度慢、易陷入局部最优解的问题,提出一种改进的遗传算法. 在适应度函数中增加带有惩罚项的平滑度函数; 引入精英保留机制,保留每一代最优个体; 自适应调整交叉概率和变异概率,使交叉概率和变异概率随进化次数变化而变化. 利用MATLAB在两种障碍物地图中与其他两种算法进行仿真对比分析,实验结果表明,改进后的算法在路径规划的应用中有效减少了机器人的转弯次数,提高了逃离局部最优路径的能力,寻优能力更强. 相似文献
112.
113.
以栅格法和粒子群算法为基础,提出了一种新的机器人实时全局最优路径规划方法.该方法包括采用栅格法对环境进行建模和直接运用粒子群算法在环境模型中搜索全局最优路径.在计算机上进行了仿真,仿真结果证明了该方法的可行性和有效性. 相似文献
114.
Rosalinda Madonna Stefania Moscato Enza Polizzi Damiana Pieragostino Maria Concetta Cufaro Piero Del Boccio Francesco Bianchi Raffaele De Caterina Letizia Mattii 《International journal of molecular sciences》2021,22(11)
Cardiac connexins (Cxs) are proteins responsible for proper heart function. They form gap junctions that mediate electrical and chemical signalling throughout the cardiac system, and thus enable a synchronized contraction. Connexins can also individually participate in many signal transduction pathways, interacting with intracellular proteins at various cellular compartments. Altered connexin expression and localization have been described in diseased myocardium and the aim of this study is to assess the involvement of Cx43, Cx26, and some related molecules in ponatinib-induced cardiac toxicity. Ponatinib is a new multi-tyrosine kinase inhibitor that has been successfully used against human malignancies, but its cardiotoxicity remains worrisome. Therefore, understanding its signaling mechanism is important to adopt potential anti cardiac damage strategies. Our experiments were performed on hearts from male and female mice treated with ponatinib and with ponatinib plus siRNA-Notch1 by using immunofluorescence, Western blotting, and proteomic analyses. The altered cardiac function and the change in Cxs expression observed in mice after ponatinib treatment, were results dependent on the Notch1 pathway and sex. Females showed a lower susceptibility to ponatinib than males. The downmodulation of cardiac Cx43, Cx26 and miR-122, high pS368-Cx43 phosphorylation, cell viability and survival activation could represent some of the female adaptative/compensatory reactions to ponatinib cardiotoxicity. 相似文献
115.
结合《轮胎工业》创刊40年来的报道内容,综述我国轮胎工业40年来的发展历程。我国轮胎生产从最初的使用棉帘线、天然橡胶生产斜交轮胎,通过不断的技术攻关,逐步发展到生产子午线轮胎、无内胎轮胎、扁平化轮胎,进而到航空轮胎、绿色轮胎、安全轮胎、智能轮胎,每一步发展都包含着大量科技创新和自主知识产权。发展民用航空子午线轮胎、新能源汽车轮胎、免充气轮胎等生产技术是“十四五”的发展重点。 相似文献
116.
A comparative study of high-temperature oxidation of Ni containing 1 at.% Cr and pure Ni was carried out. Instead of the conventional kinetics study using thermogravimetry, a microlithographic marker experiment was designed. Observation of the markers using cross-sectional TEM and SEM has revealed striking differences in the scale morphology, microstructures, and oxidation mechanisms between pure Ni and the Cr-doped Ni substrates. In particular, the results suggest that a small addition of Cr promotes significant inward transport of oxygen. Marker experiments revealed that NiO grown on pure Ni is wholly attributable to outward-cation diffusion. In contrast, NiO grown on Ni–1 at.% Cr exhibited formation of a substantial inner layer having a submicron grain size, established by the markers to have formed from oxygen ingress. For pure Ni, voids were observed to be distributed only within oxide grains. In contrast, for Ni containing 1 at.% Cr, elongated pores formed extensively along oxide-grain boundaries. Formation of new fine-grain oxide in these pores was observed to have sometimes completely resealed the void. It is, therefore, proposed that the transport of oxygen in the case of oxide scale grown on Ni–1 at.% Cr occurs via voids (pores) formed by vacancy coalescence at the grain boundaries. 相似文献
117.
A new short-path distillation system applied to the reduction of cholesterol in butter and lard 总被引:5,自引:0,他引:5
Armando Lanzani Paolo Bondioli Carlo Mariani Liliana Folegatti Stefania Venturini Enzo Fedeli Pierre Barreteau 《Journal of the American Oil Chemists' Society》1994,71(6):609-614
A molecular distillation plant, built particularly to increase the separation efficiency and to obtain safer working conditions,
was tested to remove cholesterol from anhydrous butter and lard. A preliminary experiment was carried out with butter to evaluate
the fractionation obtained at temperatures between 190 and 250°C and residual pressures between 10−3 and 10−4 torr. A second experiment was carried out at 185°C and at the maximum operational vacuum, evaluating the fractionation achieved
within a time scale between 30 and 180 min. Cholesterol was almost completely removed during the second hour with minimal
loss of low-molecular weight triglycerides. An experiment was carried out with lard at 250°C and maximum achievable operational
vacuum (10−4 Torr), lasting approximately 6 h, and cholesterol was removed almost completely during the second hour without significant
modifications in the triglyceride composition. This situation remained constant throughout the duration of the test. 相似文献
118.
Synthesis of Dimethyl Carbonate from Methanol and Carbon dioxide using Potassium Methoxide as Catalyst under Mild Conditions 总被引:2,自引:0,他引:2
Pd-supported on WO3–ZrO2 (W/Zr atomic ratio=0.2) calcined at 1073 K was found to be highly active and selective for gas-phase oxidation of ethylene to acetic acid in the presence of water at 423 K and 0.6 MPa. Contact time dependence demonstrated that acetic acid is formed via acetaldehyde formed by a Wacker-type reaction, not through ethanol by hydration of ethylene. 相似文献
119.
120.
探讨牙科陶瓷配色的方法和机理,通过将钒锆黄、锆镨黄、锆铁红、铬铝锌红对牙科陶瓷进行配色。采用分光光度计测量了样品的L*、a*、b*值和色差,并与VitaA2和ceramcoA2瓷粉对比,研究了样品色差与配方之间的关系。 相似文献