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基于双混沌优化搜索的改进粒子群算法及应用

数学的实践与认识 2024年第4期54卷 151-161页

作者：张晓勇王仲君闫军杨忠保鹤壁职业技术学院公共基础教育学院河南鹤壁458030 武汉理工大学理学院统计系湖北武汉430070 鹤壁华盛监控设备制造有限公司河南鹤壁458000 黔南民族师范学院数学与统计学院贵州都匀558000

针对现有算法在智能电阻箱动态误差校正方面存在的收敛速度慢、计算精度低,且易进入“局部最优”的陷阱等缺点,展开对智能电阻箱动态示数校正过程的重构及设计,并对动态误差校正优化算法进行研究.在双混沌优化系统中添加扰动因子与指数... 详细信息

针对现有算法在智能电阻箱动态误差校正方面存在的收敛速度慢、计算精度低,且易进入“局部最优”的陷阱等缺点,展开对智能电阻箱动态示数校正过程的重构及设计,并对动态误差校正优化算法进行研究.在双混沌优化系统中添加扰动因子与指数自适应学习方式改进搜索策略;在粒子群算法中将惯性权重因子修正为自适应权重因子,将学习因子修正为异步线性学习因子以优化算法,进而提出一种改进的粒子群优化算法(AL-DCPSO).利用8个经典函数对算法性能进行测试后,将这种算法应用在某型号智能电阻箱动态误差校正的过程中,研究结果表明:改进后的算法具有更高的计算精度(达到0.001)与更强的寻优能力,且在优化过程中呈现出较强的自适应学习能力,计算过程较为稳定,鲁棒性有效提升,耗时在阈值范围内有所增加.其创新性在于将双混沌优化机制的优点与粒子群算法相结合,应用到智能电阻箱动态误差校正的过程中,对动态误差校正方法进行了一定拓展,为粒子群优化算法在具体实际优化过程中的关键参数选取与策略设计,有效提升算法优化性能提供了一些借鉴.

关键词：智能电阻箱双混沌优化扰动因子自适应学习粒子群算法测试函数寻优策略动态误差校正

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农业现代化语境下的土地细碎化治理理论框架

安徽农业科学 2024年第17期52卷 262-266页

作者：张晓勇王刚徐峰增南京众诚规划设计咨询有限公司江苏南京210019 灌云县自然资源和规划局江苏灌云222200

土地细碎化问题是阻碍农业现代化的主要因素之一。基于问题导向,尝试在农业现代化的语境下,从技术角度探讨土地细碎化治理的理论框架:首先通过构建区域未来农业现代化场景和农业生产要素配置范式,建立针对本区域的问题识别标准和参照物... 详细信息

土地细碎化问题是阻碍农业现代化的主要因素之一。基于问题导向,尝试在农业现代化的语境下,从技术角度探讨土地细碎化治理的理论框架:首先通过构建区域未来农业现代化场景和农业生产要素配置范式,建立针对本区域的问题识别标准和参照物;以现状调查数据为基础,以范式特征为标准,进行土地细碎化问题识别与诊断,明确问题地块、农户、区域以及问题类型和影响程度;以问题可视化成果为基础,制定治理方案;通过方案评价,判别治理方案可行性,优化治理方案。土地细碎化治理理论框架的建立,有助于解决土地细碎化治理理论规范与农民认知之间的融合问题,为治理实践寻求有效路径。

关键词：农业现代化土地细碎化要素配置范式理论框架

Dorsal root entry zone coagulation for treatment of deafferentation pain syndromes

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Chinese Medical Journal 2008年第12期121卷 1089-1092页

作者： zhang xiao-hua LI yong-jie HU yong-sheng TAO Wei ZHENG Zhe Beijing Institute of Functional Neurosurgery Xuanwu Hospital Capital Medical University Beijing 100053 China

Background Deafferentation pain is a kind of chronic pain syndrome and hard to manipulate. To evaluate the effectiveness and safety of junctional dorsal root entry zone （DREZ） coagulation, 23 consecutive patients with intractable deafferentation pain syndrome were studied.Methods Twenty-three patients underwent junctional DREZ coagulation （C5-T1 for upper extremities and L2-S1 for lower extremities） under general anesthesia. The pain severity was evaluated by the short McGill pain questionnaire （MPQ） and the visual analog scale （VAS）, and the depression and anxiety of patients were assessed by Hamilton rating scale for depression （HRSD）, Hamilton anxiety scale （HAMA）, self-rating anxiety scale （SAS） and self-rating depression scale （SDS）.Results All the patients experienced significant pain reduction immediately after surgery. The scales of short MPQ and VAS at pre-operation, 6-month and 12-month follow-up were 31.5±3.4 and 8.8±1.5, 6.5±1.9 and 2.5±2.2, 7.1±2.1 and 2.9±1.9, respectively. The postoperative scores comparing to pre-operative scores showed a statistically significant difference （P 〈0.01）. The depression and anxiety state was also significantly relieved. At 12-month follow-up 6 patients had complete pain relief, 11 had excellent results with more than 75% pain relief, 17 had good results with more than 50% pain relief （73.9%）. The main postoperative complications were transient slight hemiplegia （8）, hypesthesia and paresthesia （15）, a bearing down feeling of affected extremity （6）, and deep sensory disability in the lower limbs （4） on the operated side. Because of the long time and prone position of the operation, 13 cases had a transient hyperalgesia in the upper chest. Conclusion DREZ coagulation is a safe and effective procedure in the treatment of deafferentation pain syndromes.

关键词： deafferentation pain dorsal roat entry zone coagulation

Effect of oxide inclusions on MnS precipitates and tensile mechanical property of high-strength low-alloy steel

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Journal of Iron and Steel Research International 2024年第5期31卷 1210-1220页

作者： xiao-yong Gao Hong Wei Li-feng zhang School of Mechanical Engineering Yanshan UniversityQinhuangdao066004HebeiChina School of Materials Science and Engineering Yanshan UniversityQinhuangdao066004HebeiChina School of Mechanical and Materials Engineering North China University of TechnologyBeijing100144China

The key role of oxide inclusions on the microstructure and mechanical property of a high-strength low-alloy steel was *** field emission scanning electron microscope equipped with energy-dispersive spectrometry was used to characterize MnS *** inclusions play an important role in the shape control of MnS *** oxides fovored to decrease the size and the aspect ratio of MnS *** less oxide inclusions in the steel,approximately over 16.7%MnS precipitates were with aspect ratio a>5 and pure MnS precipitates accounted for 75.9%in ***,with more oxide inclusions in the steel,only 7.4%MnS precipitates were with a>5 and pure MnS precipitates accounted for 60.1%in *** of MnS by oxide inclusions improved the strength and inhibited the *** oxide inclusions in the steel increased the yield strength and tensile strength of the steel in both longitudinal and transverse directions,and lowered the anisotropy of the mechanical property.

关键词： High-strength low-alloy steel MnS Oxide inclusion Mechanical property Anisotropy

A management information system for mine railway transportation equipment

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Journal of China University of Mining and Technology 2008年第3期18卷 373-376页

作者： LI Mei-yu HAN Ke-qi zhang xiao-yong LI xiao-lin ZHAI yong-jun YU Wei-hu School of Mines China University of Mining ＆ Technology Xuzhou Jiangsu 221008 China Railway Operators and Manufacturers of Shanxi Luan Mining Group Company Changzhi Shanxi 046000 China

Good equipment management is essential for the day to day management of an enterprise. Targeted at production opera-tion of the railway transportation department of a mining group and aimed at mine railway equipment management, we have estab-lished a management information system for the equipment in the entire process of the life cycle of equipment. The project deals with basic data about equipment, initial management, maintenance, operation and even disposal, based on a C/S and B/S structure. We adopted an object-oriented approach, dealing with software engineering, information engineering, economic and organizational measures. Thus, effective monitoring and control of the operation of railway equipment and its status in the entire process has been achieved.

关键词： mine railway transportation equipment management information system

Synthesis, Structure, and the Second-order Nonlinear Optical Properties of a Borate-carboxylic Acid Compound: KB[L-（-）-C4H4O5]2·H2O

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Chinese Journal of Structural Chemistry 2019年第8期38卷 1398-1403页

作者： YANG Kun YANG Ming yong Sheng-Li zhang xiao-yong LUO Jun-Hua Teachers College Inner Mongolia University of Science and TechnologyBaotou 014030China State Key Laboratory of Structural Chemistry Fujian Institute of Research on the Structure of MatterChinese Academy of SciencesFuzhou 350002China

A new organic-inorganic hybrid noncentrosymmetric potassium bis(malic acid)-borates KB(L-(-)-C4H4O5)2·H2O was synthesized by solution method. It was characterized by elemental analysis, FT-IR, TGA and single-crystal X-ray crystallography. It crystallizes in the monoclinic space group P21/c with a = 5.546(6), b = 11.985(13), c = 9.952(11) ?, β = 97.522(17)°, V = 655.8(13) ?3, Z = 2, Dc = 1.682 g/cm3, μ(MoKa) = 0.46 mm–1 and F(000) = 340. 5009 reflections were measured and 2893 independent reflections(Rint = 0.051) were used for further refinement. Single-crystal X-ray diffraction reveals that the complex exhibits a threedimensional pseudo tunnel structure consisting of fundamental building block [B(L-(-)-C4H4O5)2]– anions. The small cavities are occupied by the H2O molecules, which stabilize the whole structure by O–H×××O hydrogen bonds. The complex exhibits nonlinear optical effect as high as 1.5 times that of KDP standard.

关键词： synthesis structure second-order nonlinear optical borate-carboxylic acid

Impact wear properties of dissimilar joints between bainitic frogs and pearlite rails

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Journal of Iron and Steel Research International 2024年第1期31卷 275-287页

作者： Pin-yong Zeng Chun-guang Zuo xiao-yu zhang Wei Li Tribology Research Institute Southwest Jiaotong UniversityChengdu610031SichuanChina

The impact wear behavior and damage mechanism of dissimilar welded joints between U26Mn frog and U75 V rail before and after normalizing treatment were studied by cyclic impact *** experiment indicated that the impact wear volume of the joints increased with the increasing number of impact *** main wear mechanisms include pitting wear,mild fatigue wear,delamination wear,and fatigue wear,and plastic deformation was the primary impact wear *** them,fatigue wear had the greatest influence on wear volume,while other wear mechanisms had limited *** impact wear resistance of the base material was better than that of the heat-affected *** treatment was beneficial to improving the impact wear resistance of welded joints owing to its effect to promote pearlite recovery,grain refinement,and uniform distribution of *** martensite generated in the rail welded joints aggravated the impact wear damage to the materials,which should be avoided.

关键词： Dissimilar welded joint Impact wear Bainitic steel Damage mechanism Wear rate

Improving flangeability of multiphase steel by increasing microstructural homogeneity

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Journal of Iron and Steel Research International 2024年第7期31卷 1736-1745页

作者： xiao-yu Yang yong-gang Yang Xing Fang Han-long zhang Zhen-li Mi Beijing Advanced Innovation Center for Materials Genome Engineering Institute of Engineering TechnologyUniversity of Science and Technology BeijingBeijing 100083China Shanghai Baosteel Group Corp.Technology Center Shanghai 201900China

Multiphase microstructure significantly increases the strength,usually at the expense of flangeability because of lacking microstructure *** further improve the strength-flangeability of multiphase steel,the microstructural homogeneity was advanced by adjusting the hard martensite/austenite(M/A)*** strength-flangeability was measured via uniaxial tensile tests and hole expansion *** microstructures were characterized using a scanning electron microscope equipped with an electron backscatter diffraction detector and a transmission electron *** tests were supplementally used to quantitatively reveal the microstructural homogeneity of the *** show that the adjusted multiphase steel achieves an excellent ultimate tensile strength(~800 MPa)and flangeability(~135%hole expansion ratio).A promising homogeneous multiphase microstructure was obtained by controlling undercooled austenite transformed at about 600℃.This microstructure consists of soft polygonal ferrite,blocky bainitic ferrite,and hard M/A *** volume fraction of M/A islands is around 5%,and the average size is less than l *** nanoindentation analysis indicated that the participation of M/A islands impressively influenced the microstructural *** strain partition and better mechanical compatibility were present in the adjusted multiphase steel since the plasticity initiation started late,which resulted in a positive ***,avoiding M/A islands distributed in the chain along the rolling direction on the matrix hindered the possibility of voids coalescing into cracks and stabilized the flanging performance.

关键词： Multiphase steel Flangeability Martensite/austenite island-Microstructural homogeneity-Microstructure Compact strip production process

Hot Compression Behavior and Tensile Property of a Novel Ni-Co-Based Superalloy Prepared by Electron Beam Smelting Layered Solidification Technology

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Acta Metallurgica Sinica(English Letters) 2024年第2期37卷 283-292页

作者： yong-Chao Gai Rui zhang Chuan-yong Cui Zi-Jian Zhou Yi Tan Yi-Zhou Zhou xiao-Feng Sun Key Laboratory of Materials Modification by Laser Ionand Electron Beams(Ministry of Education)School of Materials Science and EngineeringDalian University of TechnologyDalian116024China Shi-Changxu Innovation Center for Advanced Materials Institute of Metal ResearchChinese Academy of SciencesShenyang110016China

The hot compression behavior and tensile strength after compression of a new Ni-Co-based superalloy produced using electron beam smelting layered(EBSL)solidification technology were *** compression tests were performed at temperatures of 1120℃and 1150℃,with strain rates of 1 s^(-1) and 0.01 s^(-1),reaching a true strain of *** strength was evaluated at room *** results revealed that this EBSL technology accelerates dynamic recrystallization(DRX),without compromising the strength of alloy.A significant correlation between the volume fraction of DRX and the strain rate was observed,with higher fractions at lower strain rates,leading to higher tensile ***,at the same strain rate,the specimens compressed at 1120℃exhibited higher tensile strength due to undissolvedγ′*** solution and aging heat treatment,the alloy maintained high tensile *** results suggested that the EBSL Ni-Co-based superalloy offers excellent prospects for practical applications.

关键词： Ni-Co-based superalloy Hot deformation Electron beam smelting Tensile strength