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Fire Technology - The current research on individual risks mainly focuses on the individual risk considering a single fire or the spatial distribution of multiple fires. It is more realistic to... 相似文献
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Jiang Guo Xing-Yu Wang Yong Zhao Chen-Yi Hou Xu Zhu Yin-Di Cai Zhu-Ji Jin Ren-Ke Kang 《先进制造进展(英文版)》2022,10(3):368-381
The tool state exerts a strong influence on surface quality and profile accuracy during precision/ultraprecision machining. However, current on-machine measurement methods cannot precisely obtain the tool nose radius and wear. This study therefore investigated the onmachine measurement of tool nose radius on the order of hundreds of microns and wear on the order of a few microns to tens of microns during precision/ultra-precision machining using the edge reversal method. To provide the necessary replication, pure aluminum and pure copper soft metal substrates were evaluated, with pure copper exhibiting superior performance. The feasibility of the measurement method was then demonstrated by evaluating the replication accuracy using a 3D surface topography instrument; the measurement error was only 0.1%. The wear of the cutting tool was measured using the proposed method to obtain the maximum values for tool arc wear, flank wear, and wear depth of 3.4 lm, 73.5 lm and 3.7 lm, respectively.The full text can be downloaded at https://link.springer.com/article/10.1007/s40436-022-00397-y 相似文献
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通过使用ARL8820直读光谱仪,LECO氧氮氢气体分析仪和铂铑热电偶等方法,研究了40Mn2圆钢中的Als、N和连铸钢液过热度对钢材裂纹的影响。结果表明:Als、N和连铸钢液的过热度分别为0.021%~0.035%,0.0065%~0.0083%和32~46℃的炉次Φ50~60 mm轧材表面出现了裂纹。工艺改进后,控制钢中的Als 0.015%~0.025%,[N]≤0.0060%,连铸钢液过热度18~30℃,连铸坯表面未出现裂纹,保证了轧材表面质量。 相似文献
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Shi-Wei Bai Xiao-Fei Yang Shu-Jing Wang Yong-Chao Liu Peng Zhang Yin-Shen Liu Han-Rui Hu Yang-Fan Guo Jin Wang Ze-Yu Du Zhou Yan Yun-Kai Zhang Yan-Lin Ye Qi-Te Li Yu-Cheng Ge Chuang-Ye He 《核技术(英文版)》2022,33(1):98-106
Collinear laser spectroscopy is a powerful tool for studying the nuclear spins,electromagnetic moments,and charge radii of exotic nuclei.To study the nuclear properties of unstable nuclei at the Beijing Radioactive Ion-beam Facility (BRIF) and the future High Intensity Heavy-ion Accelerator Facility (HIAF),we developed a collinear laser spectroscopy apparatus integrated with an offline laser ablation ion source and a laser system.The overall performance of this state-of-the-art technique was eva... 相似文献
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Clustering divides objects into groups based on similarity. However, traditional clustering approaches are plagued by their difficulty in dealing with data with complex structure and high dimensionality, as well as their inability in solving multi-objective data clustering problems. To address these issues, an evolutionary state-based novel multi-objective periodic bacterial foraging optimization algorithm (ES-NMPBFO) is proposed in this article. The algorithm is designed to alleviate the high-computing complexity of the standard bacterial foraging optimization (BFO) algorithm by introducing periodic BFO. Moreover, two learning strategies, global best individual (gbest) and personal historical best individual (pbest), are used in the chemotaxis operation to enhance the convergence speed and guide the bacteria to the optimum position. Two elimination-dispersal operations are also proposed to prevent falling into local optima and improve the diversity of solutions. The proposed algorithm is compared with five other algorithms on six validity indexes in two data clustering cases comprising nine general benchmark datasets and four credit risk assessment datasets. The experimental results suggest that the proposed algorithm significantly outperforms the competing approaches. To further examine the effectiveness of the proposed strategies, two variants of ES-NMPBFO were designed, and all three forms of ES-NMPBFO were tested. The experimental results show that all of the proposed strategies are conducive to the improvement of solution quality, diversity and convergence. 相似文献
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Cui Ying Guo Dongyan Shao Yanyan Wang Zhenhua Shen Chunhua Zhang Liyan Chen Shengyong 《International Journal of Computer Vision》2022,130(2):550-566
International Journal of Computer Vision - Visual tracking of generic objects is one of the fundamental but challenging problems in computer vision. Here, we propose a novel fully convolutional... 相似文献