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Shape and Size Optimization of Truss Structures under Frequency Constraints Based on Hybrid Sine Cosine Firefly Algorithm

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Computer Modeling in Engineering & Sciences 2023年第1期134卷 405-428页

作者： Ran Tao xiaomeng yang Huanlin Zhou Zeng Meng School of Civil Engineering Hefei University of TechnologyHefei230009China

Shape and size optimization with frequency constraints is a highly nonlinear problem withmixed design variables,non-convex search space,and multiple local optima.Therefore,a hybrid sine cosine firefly algorithm(HSCFA)is proposed to acquire more accurate solutions with less finite element analysis.The full attraction model of firefly algorithm(FA)is analyzed,and the factors that affect its computational efficiency and accuracy are revealed.A modified FA with simplified attraction model and adaptive parameter of sine cosine algorithm(SCA)is proposed to reduce the computational complexity and enhance the convergence rate.Then,the population is classified,and different populations are updated by modified FA and SCA respectively.Besides,the random search strategy based on Lévy flight is adopted to update the stagnant or infeasible solutions to enhance the population diversity.Elitist selection technique is applied to save the promising solutions and further improve the convergence rate.Moreover,the adaptive penalty function is employed to deal with the constraints.Finally,the performance of HSCFA is demonstrated through the numerical examples with nonstructural masses and frequency constraints.The results show that HSCFA is an efficient and competitive tool for shape and size optimization problems with frequency constraints.

关键词： Firefly algorithm sine cosine algorithm frequency constraints structural optimization

Electrospun porous carbon nanofibers derived from bio-based phenolic resins as free-standing electrodes for high-performance supercapacitors

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Frontiers of Chemical Science and Engineering 2023年第5期17卷 504-515页

作者： Yongsheng Zhang xiaomeng yang Jinpan Bao Hang Qian Dong Sui Jianshe Wang Chunbao Charles Xu Yanfang Huang School of Chemical Engineering Zhengzhou UniversityZhengzhou 450001China School of Chemistry and Chemical Engineering Luoyang Normal UniversityLuoyang 471934China Department of Chemical and Biochemical Engineering Western UniversityLondonN6A 3K7Canada

Phenolic resins were employed to prepare electrospun porous carbon nanofibers with a high specific surface area as free-standing electrodes for high-performance supercapacitors.However,the sustainable development of conventional phenolic resin has been challenged by petroleum-based phenol and formaldehyde.Lignin with abundant phenolic hydroxyl groups is the main non-petroleum resource that can provide renewable aromatic compounds.Hence,lignin,phenol,and furfural were used to synthesize bio-based phenolic resins,and the activated carbon nanofibers were obtained by electrospinning and one-step carbonization activation.Fourier transform infrared and differential scanning calorimetry were used to characterize the structural and thermal properties.The results reveal that the apparent activation energy of the curing reaction is 89.21 kJ·mol–1 and the reaction order is 0.78.The activated carbon nanofibers show a uniform diameter,specific surface area up to 1100 m^(2)·g^(-1),and total pore volume of 0.62 cm^(3)·g^(-1).The electrode demonstrates a specific capacitance of 238 F·g^(-1)(0.1 A·g^(-1))and good rate capability.The symmetric supercapacitor yields a high energy density of 26.39 W·h·kg^(-1)at 100 W·kg^(-1)and an excellent capacitance retention of 98%after 10000 cycles.These results confirm that the activated carbon nanofiber from bio-based phenolic resins can be applied as electrode material for high-performance supercapacitors.

关键词： lignin bio-based phenolic resins electrospinning activated carbon nanofibers supercapacitors

Short-term biochar effect on soil physicochemical and microbiological properties of a degraded alpine grassland

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Pedosphere 2022年第3期32卷 426-437页

作者： Jinsheng LI Xinqing SHAO Ding HUANG Kesi LIU Jianying SHANG Qian ZHANG Tianci ZHAO xiaomeng yang College of Grassland Science and Technology China Agricultural UniversityBeijing 100193(China) National Field Station of Grassland Ecosystem at Guyuan Hebei 076550(China) Department of Water and soil Science China Agricultural UniversityBeijing 100193(China)

Soil remediation is an important part of the restoration process of degraded terrestrial ecosystems.Due to its unique properties,biochar is being used widely as an effective soil modifier in agricultural systems,but research is still rare on biochar application in grassland ecosystems,especially in degraded alpine grasslands.In this study,we conducted a plot experiment to investigate the effect of biochar application on soil physicochemical properties and microorganisms at the 0–20 cm soil depth of a degraded alpine grassland in Qinghai-Tibet Plateau,China.The experiment consisted of four corn straw biochar application levels(0%,0.5%,1%and 2%,with the percentage representing the ratio of biochar weight to the dry weight of soil in the surface 20 cm soil layer).When the biochar addition increased from 0%to 2%,total nitrogen,total organic carbon and available phosphorus in the 0–10 cm soil layer increased by 41%,55%and 45%,respectively,in the second year after biochar addition.Meanwhile,soil electrical conductivity decreased,and soil water content increased.Total microbial,fungal and bacterial biomasses in the 0–10 cm soil layer increased from 9.15 to 12.68,0.91 to 1.34,and 3.85 to 4.55μg g^(-1),respectively.The relative biomasses of saprophytic fungi and methanotrophic bacteria decreased,while the relative biomasses of ectomycorrhizal fungi and arbuscular mycorrhizal fungi increased.These results indicate that biochar has a great potential in improving microbial activity and soil fertility in soil remediation of the degraded alpine grassland.

关键词： bacteria fungi microbial community phosphatase soil fertility soil modifier soil remediation urease

急诊重症监护室急性失代偿性肺高压患者的预后及其危险因素分析

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中国医科大学学报 2024年第6期53卷 555-560,564页

作者：杨晓曚陶维晨中国医科大学附属盛京医院急诊科沈阳110004

目的探讨急性失代偿性肺高压患者的预后及其危险因素,旨在为急性失代偿性肺高压患者的临床管理提供依据。方法选取2015年4月至2020年4月我院急诊重症监护室诊治的287例急性失代偿性肺高压患者。根据是否发生院内死亡将患者分为生存组(n=... 详细信息

目的探讨急性失代偿性肺高压患者的预后及其危险因素,旨在为急性失代偿性肺高压患者的临床管理提供依据。方法选取2015年4月至2020年4月我院急诊重症监护室诊治的287例急性失代偿性肺高压患者。根据是否发生院内死亡将患者分为生存组(n=140)和死亡组(n=147)。比较2组患者临床特征、实验室检查、治疗方案、临床事件及预后情况。利用多因素回归分析评价患者院内死亡率与欧洲心脏学会/欧洲呼吸学会(ESC/ERS)风险评估体系及SOFA评分的相关性。利用受试者操作特征(ROC)曲线分析ESC/ERS风险评估体系及SOFA评分对患者临床预后的评价效能。结果与生存组比较,死亡组ERS/ESC危险分层中、高危险及纽约心脏学会心功能分级Ⅲ、Ⅳ级比例显著增加;平均肺动脉压和N末端B型利钠肽原(NT-proBNP)明显升高;动脉血氧分压(PaO2)及三尖瓣环收缩期运动幅度(TAPSE)明显降低,差异均有统计学意义(均P<0.05)。多因素分析结果显示,SOFA评分≥8、ESC/ERS危险分级高危、NT-proBNP和PaO2是急性失代偿性肺高压患者院内死亡的独立危险因素(均P<0.05)。ROC曲线分析结果显示,ERS/ESC危险分级高危联合SOFA评分≥8的曲线下面积最大,为0.877;灵敏度为92.5%,特异度为83.0%。结论ERS/ESC危险分级高危及SOFA评分≥8是预测急性失代偿性肺高压患者院内死亡的独立危险因素。ERS/ESC危险分级及SOFA评分可以作为评价重症监护病房中急性失代偿性肺高压患者预后的指标,且二者联合的预测效能更高。

关键词：急性失代偿性肺高压急诊重症监护室预后危险因素

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基于改进正余弦算法的抱杆结构优化

应用数学和力学 2024年第5期45卷 529-538页

作者：杨小猛李亮胡雄飞周焕林合肥工业大学土木与水利工程学院合肥230009 国网安徽省电力有限公司建设分公司合肥230071 国网安徽省电力有限公司安庆供电公司安徽安庆246001

抱杆是组立输电铁塔的特种起重设备.以最小质量为优化目标,杆件的截面尺寸、辅材连接方式以及摇臂节点坐标为优化变量,许用应力、位移和屈曲系数为约束条件,建立抱杆优化设计模型.提出一种改进的正余弦算法(improved sine cosine algori... 详细信息

抱杆是组立输电铁塔的特种起重设备.以最小质量为优化目标,杆件的截面尺寸、辅材连接方式以及摇臂节点坐标为优化变量,许用应力、位移和屈曲系数为约束条件,建立抱杆优化设计模型.提出一种改进的正余弦算法(improved sine cosine algorithm,ISCA),开展抱杆尺寸、形状和拓扑优化.引入Lévy飞行增强算法全局搜索能力,采用精英引导策略增强算法局部搜索能力,使用贪婪选择策略更新最优解.算例表明ISCA能够有效求解空间桁架结构的优化设计问题.

关键词：正余弦算法抱杆桁架结构结构优化有限元分析

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加快构建具有东北特色优势的现代化产业体系

行政与法 2024年第2期 91-102页

作者：吴刚杨晓猛中共大连市委党校(大连行政学院、大连市社会主义学院)经济学教研部

新时代推动东北全面振兴,要准确把握习近平总书记关于构建具有东北特色优势现代化产业体系的重要论述,加快形成新质生产力。新质生产力是现代生产力演进的一种能级跃迁,是以科技创新驱动高质量发展的现代生产力。形成新质生产力的关键... 详细信息

新时代推动东北全面振兴,要准确把握习近平总书记关于构建具有东北特色优势现代化产业体系的重要论述,加快形成新质生产力。新质生产力是现代生产力演进的一种能级跃迁,是以科技创新驱动高质量发展的现代生产力。形成新质生产力的关键要素包括创新型人才、科技创新和制度创新。推动东北全面振兴关键在科技创新,方向是产业升级,根基在实体经济。加快构建具有东北特色优势的现代化产业体系,要夯实实体经济根基,以数智化转型赋能传统制造业高质量发展,培育战略性新兴产业增强发展新动能,培育未来产业抢占未来发展制高点。

关键词：新质生产力现代化产业体系东北特色优势

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乡村基层矛盾纠纷多元化解机制创新研究

长春市委党校学报 2024年第2期 21-27页

作者：杨晓猛吴刚大连市委党校经济学教研部中共大连市委党校经济学教研部

基层矛盾纠纷多元化解机制需要党建引领的多元主体参与、组织领导的部门联动制度、以民为本的网格管理运行。基于对﹡市乡镇的问卷、走访调研,当前乡村基层矛盾纠纷多元化解面临的问题主要表现为:基层调解队伍薄弱,整体待遇保障偏低;上... 详细信息

基层矛盾纠纷多元化解机制需要党建引领的多元主体参与、组织领导的部门联动制度、以民为本的网格管理运行。基于对﹡市乡镇的问卷、走访调研,当前乡村基层矛盾纠纷多元化解面临的问题主要表现为:基层调解队伍薄弱,整体待遇保障偏低;上下部门协同不畅,基层党员结构失调;数据治理水平不高,组织机制尚未完善;工作方式创新不足,属地管理权责不一。提升基层矛盾纠纷多元化解法治保障能力,应从以下几点着手:加强制度建设,壮大基层调解队伍;推进部门联动,实现组织协同治理;跟进技术升级,完善组织保障机制;创新治理方式,理顺基层管理体系。

关键词：基层矛盾多元化解乡村治理机制创新

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Antibacterial surfaces:Strategies and applications

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Science China(Technological Sciences) 2022年第5期65卷 1000-1010页

作者： yang xiaomeng HOU JianWen TIAN Yuan ZHAO JingYa SUN QiangQiang ZHOU ShaoBing Key Laboratory of Advanced Technologies of Materials Ministry of EducationSchool of Materials Science and EngineeringSouthwest Jiaotong UniversityChengdu610031China School of Life Science and Engineering Southwest Jiaotong UniversityChengdu610031China

Antibacterial surfaces are surfaces that can resist bacteria,relying on the nature of the material itself.It is significant for safe food and water,human health,and industrial equipment.Biofilm is the main form of bacterial contamination on the material surface.Preventing the formation of biofilm is an efficient way to develop antibacterial surfaces.The strategy for constructing the antibacterial surface is divided into bacteria repelling and bacteria killing based on the formation of the biofilm.Material surface wettability,adhesion,and steric hindrance determine bacteria repelling performance.Bacteria should be killed by surface chemistry or physical structures when they are attached to a material surface irreversibly.Killing approaches are usually in the light of the cell membrane of bacteria.This review summarizes the fabrication methods and applications of antibacterial surfaces from the view of the treatment of the material surfaces.We also present several crucial points for developing long-term stability,no drug resistance,broad-spectrum,and even programable antibacterial surfaces.

关键词： antibacterial surface bacteria repelling bacteria killing

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氨硼烷催化水解制氢综合实验设计

实验室研究与探索 2024年第1期43卷 147-151页

作者：武美霞杨肖萌王俊丽张三兵李作鹏山西大同大学化学与化工学院山西大同037009 中国农业大学理学院应用化学系北京100193

根据物理化学实验教学的需求,设计了氨硼烷催化水解制氢综合探索性实验。采用化学还原法制备了新型镍硼纳米催化剂,将其用于氨硼烷水解催化反应,考察催化剂用量和温度对反应速率的影响,并根据阿雷尼乌斯公式测定反应的活化能。通过探索... 详细信息

根据物理化学实验教学的需求,设计了氨硼烷催化水解制氢综合探索性实验。采用化学还原法制备了新型镍硼纳米催化剂,将其用于氨硼烷水解催化反应,考察催化剂用量和温度对反应速率的影响,并根据阿雷尼乌斯公式测定反应的活化能。通过探索性操作完成整个实验流程,学生不仅可以掌握催化剂的化学还原法制备技术,还可以强化和巩固利用化学动力学知识分析处理实验数据的能力。

关键词：氨硼烷储氢材料制氢实验教学