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A Multi-strategy Improved Snake Optimizer Assisted with Population Crowding Analysis for Engineering Design Problems

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Journal of Bionic Engineering 2024年第3期21卷 1567-1591页

作者： Lei Peng Zhuoming Yuan Guangming Dai maocai wang Jian Li Zhiming Song Xiaoyu Chen School of Computer Science China University of GeosciencesWuhan430074China Hubei Key Laboratory of Intelligent Geo-Information Processing China University of GeosciencesWuhan430074China China Astronautics Standards Institute Beijing100071China

Snake Optimizer(SO)is a novel Meta-heuristic Algorithm(MA)inspired by the mating behaviour of snakes,which has achieved success in global numerical optimization problems and practical engineering ***,it also has certain drawbacks for the exploration stage and the egg hatch process,resulting in slow convergence speed and inferior solution *** address the above issues,a novel multi-strategy improved SO(MISO)with the assistance of population crowding analysis is proposed in this *** the algorithm,a novel multi-strategy operator is designed for the exploration stage,which not only focuses on using the information of better performing individuals to improve the quality of solution,but also focuses on maintaining population *** boost the efficiency of the egg hatch process,the multi-strategy egg hatch process is proposed to regenerate individuals according to the results of the population crowding *** addition,a local search method is employed to further enhance the convergence speed and the local search *** is first compared with three sets of algorithms in the CEC2020 benchmark functions,including SO with its two recently discussed variants,ten advanced MAs,and six powerful CEC competition *** performance of MISO is then verified on five practical engineering design *** experimental results show that MISO provides a promising performance for the above optimization cases in terms of convergence speed and solution quality.

关键词： Snake optimizer Multi-strategy Population crowding analysis Engineering design problem

An Efficient Method of Generating Parameters for Pairing-Based Cryptosystems

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China Communications 2010年第4期7卷 167-171页

作者： wang maocai DAI Guangming PEN Lei ZHEN Chang QIN Ruijie School of Computer China University of Geosciences Wuhan 430074 China

Efficient computation of Tate pairing is a crucial factor for practical applications of pairing-based cryptosystems(PBC).Recently,there have been many improvements for the computation of Tate pairing,which focuses on the arithmetical operations above the finite *** this paper,we analyze the structure of Miller’s algorithm firstly,which is used to implement Tate *** on the characteristics that Miller’s algorithm will be improved tremendous if the order of the subgroup of elliptic curve group is low hamming prime,a new method for generating parameters for PBC is put forward,which enable it feasible that there is certain some subgroup of low hamming prime order in the elliptic curve group ***,we analyze the computation efficiency of Tate pairing using the new parameters for PBC and give the test *** is clear that the computation of Tate pairing above the elliptic curve group generating by our method can be improved tremendously.

关键词： Pairing-based Cryptosystems Miller's Algorithm Tate Pairing Low Hamming Elliptic Curve

Oxygen Permeation Behaviors and Hardening Effect of Titanium Alloys at High Temperature

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Journal of Materials Science & Technology 2004年第6期20卷 719-723页

作者： Hongyan MA, maocai wang and Weitao WUState Key Laboratory for Corrosion and Protection, Institute of Metai Research, Chinese Academy of Sciences, Shenyang 110016, ChinaGraduate School of the Chinese Academy of Sciences, Beijing 100039, China Lab. for Corrosion and Protection Inst. of Metal Res. Chinese Acad. of Sci. Shenyang 110016 China Graduate Sch. Chinese Acad. of Sci. Beijing 100039 China

In order to improve the surface hardness and wear resistance of Ti and Ti alloy components, an oxygen permeation treatment (OPT) was developed. The oxygen permeation behaviors of three Ti alloys, TA2, TB5 and TC11, treated in air with O-P medium at high temperature have been studied. The results show that the 0-P treatment can significantly improve the surface hardness of Ti alloys. The oxidation mass-gain of β-Ti alloy (TB5) is much higher than α-Ti alloy (TA2) under the same condition, while α+β Ti alloy (TC11) is the lowest. All the Ti alloys treated at this condition produce two surface layers: the outer layer consists mainly of TiO2, as well as trace of other oxides, and the inner layer consists of a Ti-O interstitial solid solution formed by the diffusion of oxygen in α crystal lattice. Thick scales of β Ti alloy (TB5) are easily formed depending mainly on the poor solid solution content of oxygen, while deep solution layer can be formed since partial β phase has been transformed into α phase. The scales of α-β Ti alloy (TC11) are very thin and compact. Aluminum-rich zone, as well as deficient zone, is found in oxide layers. A crystallographic characterization of oxygen solution layer has been performed and evaluated by crystallographic lattice constant.

关键词： Microstructure Oxygen permeation Titanium Solid solution

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K403高温合金缺损叶片的粉末冶金法修复

稀有金属材料与工程 2015年第9期44卷 2222-2227页

作者：张杰翟玉春王茂才东北大学辽宁沈阳110819 中国科学院金属研究所腐蚀与防护国家重点实验室辽宁沈阳110016

采用粉末冶金修复工艺(China Powder Metallurgy,CPM),利用2种分别混有微量硼合金和纳米镍粉的镍基高温合金粉末对K403缺损叶片进行修复再制造。采用X射线衍射、扫描电子显微镜(SEM)、EDX能谱和电子探针(EPMA)对叶片修复区的相组成、宏... 详细信息

采用粉末冶金修复工艺(China Powder Metallurgy,CPM),利用2种分别混有微量硼合金和纳米镍粉的镍基高温合金粉末对K403缺损叶片进行修复再制造。采用X射线衍射、扫描电子显微镜(SEM)、EDX能谱和电子探针(EPMA)对叶片修复区的相组成、宏观形貌及微观组织进行分析;同时对修复区致密化和界面连接机理进行初步探讨。结果表明,选用合适的修复粉末,用CPM方法能够将缺损的叶片再制造成原有形状与尺寸;混合硼合金的修复粉末对K403合金的修复效果较好;硼元素的扩散对修复区致密化和界面连接起重要作用,期间发生的反应为Ni m B n+(Cr,W)→γ+(Cr2,W)B2;经计算,在CPM工艺条件下,界面区的硼浓度可以降低至共晶浓度以下。

关键词：粉末冶金修复工艺 K403高温合金叶片

Oxidation Behaviour of Laser Remelted Cr-containing Steels

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Journal of Materials Science & Technology 1993年第4期9卷 258-262页

作者： Guanyan FU Weitao WU maocai wang Shenglong ZHU Corrosion science Lab,Institute of Corrosion and Protection of Metals,Academia Sinica,Shenyang 110015,China

Laser surface remelting of steels with different Cr contents has been performed by using a CO_2 laser. The results of oxidation tests showed that the effects of laser remelting on the oxidation resistance of Cr-containing steels have close relation to the Cr contents and microstructures of the steels. The re- sistance to high temperature oxidation of 18-8 and HK40 at 1273 K can be obviously improved by laser remelting, whereas laser remelting showed little effect on the oxidation resistance of Fe-6Cr and Cr30 at 1173-1273 K.

关键词： laser remelting oxidation Cr-containing steel

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钛合金的高温固态渗氧-扩散固溶复合处理

稀有金属材料与工程 2007年第4期36卷 685-689页

作者：马红岩王茂才魏政中国科学院金属研究所腐蚀与防护国家重点实验室沈阳黎明航空发动机集团公司辽宁沈阳110043

为了提高钛合金的表面耐磨性能,发展了一种表面无氧化膜的高温固态渗氧-扩散固溶复合处理方法(OP-DS)。利用TGA,SEM,XRD,XPS及显微硬度计对OP-DS处理后的钛合金进行了研究。结果表明:OP-DS方法能显著提高合金表面层的硬度,硬化层深度随... 详细信息

为了提高钛合金的表面耐磨性能,发展了一种表面无氧化膜的高温固态渗氧-扩散固溶复合处理方法(OP-DS)。利用TGA,SEM,XRD,XPS及显微硬度计对OP-DS处理后的钛合金进行了研究。结果表明:OP-DS方法能显著提高合金表面层的硬度,硬化层深度随预渗氧时间的延长而增加;预渗氧处理时间对扩散固溶效果有很大的影响,适当的预渗氧时间可在表面形成无膜强化固溶层。从热力学及动力学角度对渗氧-扩散固溶机理进行了探讨。

关键词：钛合金固态渗氧扩散固溶无氧化膜

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脉冲激光熔覆制备钛合金的柱状组织涂层

材料研究学报 2008年第3期22卷 322-326页

作者：王维夫孙凤久王茂才东北大学理学院沈阳110004 中国科学院金属研究所金属腐蚀与防护国家重点实验室沈阳110016

用脉冲激光熔覆方法在TC6钛合金表面制备具有柱状组织特征的钛合金涂层,研究了涂层的组织特征和液-固前沿热力学参数的变化及其对柱状组织的影响.结果表明,该涂层的组织形态具有典型的柱状特征,涂层仍由α′马氏体构成,但是其尺寸更加细... 详细信息

用脉冲激光熔覆方法在TC6钛合金表面制备具有柱状组织特征的钛合金涂层,研究了涂层的组织特征和液-固前沿热力学参数的变化及其对柱状组织的影响.结果表明,该涂层的组织形态具有典型的柱状特征,涂层仍由α′马氏体构成,但是其尺寸更加细小,柱状组织中主要合金元素分布的均匀性显著提高.柱状组织是在"液相→β相"转变过程中由G/R比值所决定的原始柱状β相结构在室温下的残留.在凝固过程中,固液界面处G/R值的变化决定了所获得的柱状β相形态的变化,并最终导致柱状组织向非柱状组织转变.

关键词：材料表面与界面激光熔覆钛合金显微组织柱状结构凝固

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凸多边形最小面积四边形包围盒算法

华中科技大学学报（自然科学版） 2006年第6期34卷 71-73页

作者：戴光明王茂才彭雷中国地质大学计算机学院湖北武汉430074

针对凸多边形的最小面积四边形包围盒问题进行研究,通过数学推导证明,得出了凸多边形的最小面积四边形包围盒的四边都是多共点边,或三边是多共点边而另一边(单共点边)中点与凸多边形的一顶点重合等一系列结论.依据此结论设计了时间复杂... 详细信息

针对凸多边形的最小面积四边形包围盒问题进行研究,通过数学推导证明,得出了凸多边形的最小面积四边形包围盒的四边都是多共点边,或三边是多共点边而另一边(单共点边)中点与凸多边形的一顶点重合等一系列结论.依据此结论设计了时间复杂度为O(n4)的算法,依据本算法可以构造出凸多边形面积最小的凸四边形包围盒,而且其算法的复杂度仅与凸多边形的边数n相关,是多项式级的复杂度.运算实例表明了算法的正确性和有效性.

关键词：凸多边形最小四边形包围盒多共点边

多次辐照条件下YAG脉冲激光熔敷层开裂敏感性研究

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中国激光 1999年第4期26卷 363-366页

作者：张松陈江王茂才吴维 中国科学院金属腐蚀与防护所金属腐蚀与防护国家重点实验室沈阳110015

采用Nd:YAG固体脉冲激光器,在镍基高温合金上激光熔敷镍基自熔合金,对激光多次辐照条件下熔敷层的开裂问题进行了探索性研究。试验结果表明:脉冲激光多次辐照,对熔敷层的组织及硬度影响不大;激光辐照次数的增多,促进了熔敷层裂纹萌生,... 详细信息

采用Nd:YAG固体脉冲激光器,在镍基高温合金上激光熔敷镍基自熔合金,对激光多次辐照条件下熔敷层的开裂问题进行了探索性研究。试验结果表明:脉冲激光多次辐照,对熔敷层的组织及硬度影响不大;激光辐照次数的增多,促进了熔敷层裂纹萌生,其裂纹形态为沿晶高温液化裂纹;对基材热输入的增多。

关键词：脉冲激光多次辐照熔敷开裂激光热处理