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Formulation of Optimization Problems with Radiation Field Phases as Design Variables for Pattern Synthesis of Linear Antenna Arrays

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China Communications 2022年第12期19卷 86-100页

作者： Fei Zhao Jun He Sanyou Zeng changhe Li Qinghui Xu Zhigao Zeng School of Mechanical Engineering and Electronic Information China University of GeosciencesWuhan 430074China Science and Technology on Blind Signal Processing Laboratory Southwest Electronics and Telecommunication Technology Research InstituteChengdu 610041China School of Automation China University of GeosciencesWuhan 430074China Hubei Key Laboratory of Advanced Control and Intelligent Automation for Complex Systems Wuhan 430074China College of Computer Hunan University of TechnologyZhuzhou CityHunan Province412007China

Pattern synthesise of antenna arrays is usually complicated optimization problems,while evolutionary algorithms(EAs)are promising in solving these problems.This paper does not propose a new EA,but does construct a new form of optimization problems.The new optimization formulation has two differences from the common ones.One is the objective function is the field error between the desired and the designed,not the usual amplitude error between the desired and the designed.This difference is beneficial to decrease complexity in some sense.The second difference is that the design variables are changed as phases of desired radiation field within shaped-region,instead of excitation parameters.This difference leads to the reduction of the number of design variables.A series of synthesis experiments including equally and unequally spaced linear arrays with different pattern shape requirements are applied,and the effectiveness and advantages of the proposed new optimization problems are validated.The results show that the proposing a new optimization formulation with less complexity is as significant as proposing a new algorithm.

关键词： pattern synthesis evolutionary algorithms linear antenna arrays

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采棉机输棉系统的研究现状与分析

新疆农机化 2024年第2期 38-41页

作者：石鑫刘延彬牛长河陈毅飞新疆农业科学院农业机械化研究所新疆乌鲁木齐830091 农业部林果棉与设施农业设备科学观测试验站新疆乌鲁木齐830091 江苏大学农业工程学院江苏镇江202123

输棉系统是采棉机的核心系统,对其研究可提高输棉系统输送能力、降低堵塞率和提高作业效率等方面起着重要作用。本文介绍了采棉机输棉系统的分类和工作原理,系统阐述了采棉机输棉系统的研究发展现状,分析了输棉系统存在问题并提出解决方... 详细信息

输棉系统是采棉机的核心系统,对其研究可提高输棉系统输送能力、降低堵塞率和提高作业效率等方面起着重要作用。本文介绍了采棉机输棉系统的分类和工作原理,系统阐述了采棉机输棉系统的研究发展现状,分析了输棉系统存在问题并提出解决方法,这为今后我国采棉机输棉系统的研制和发展提供技术支持。

关键词：采棉机输棉系统现状问题

Cu-Mn-Al三元尖晶石催化甲醇重整反应特性

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石油化工高等学校学报 2024年第2期37卷 50-57页

作者：吕昌赫吴殿卿张楷文于东北张财顺韩蛟高志贤辽宁石油化工大学石油化工学院辽宁抚顺113001

以硝酸铜为铜源、拟薄水铝石为铝源、柠檬酸为添加剂,以乙酸锰为第三组分部分取代铜,采用球磨法制备了Cu_(0.7)Mn_(0.3)Al_(2.5)三元固溶体尖晶石催化剂;借助XRD、BET、H_(2)-TPR和XPS等表征技术,对Cu_(0.7)Mn_(0.3)Al_(2.5)的晶相结构... 详细信息

以硝酸铜为铜源、拟薄水铝石为铝源、柠檬酸为添加剂,以乙酸锰为第三组分部分取代铜,采用球磨法制备了Cu_(0.7)Mn_(0.3)Al_(2.5)三元固溶体尖晶石催化剂;借助XRD、BET、H_(2)-TPR和XPS等表征技术,对Cu_(0.7)Mn_(0.3)Al_(2.5)的晶相结构、织构性质、还原性质及表面阳离子状态及分布进行研究,并在甲醇水蒸气重整制氢(MSR)反应中考察其缓释催化性能。结果表明,与Cu Al_(2.5)、Cu_(0.7)Zn_(0.3)Al_(2.5)相比,Cu_(0.7)Mn_(0.3)Al_(2.5)的晶粒最小,比表面积最大,且晶胞收缩最大,晶胞常数最小;该催化剂呈富铝状态,但表面尖晶石相Cu^(2+)占比更高,H_(2)气氛下还原难度增大,在MSR反应中表现出较好的缓释催化性能;在温度为265℃、n(H_(2)O)/n(CH_(3)OH)=2、质量空速为2.25 h^(-1)的条件下反应40 h,甲醇转化率高达84%。该研究为研发高效铜基缓释催化剂提供了数据参考。

关键词：缓释催化甲醇重整尖晶石球磨法

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Machinability of ultrasonic vibration-assisted micro-grinding in biological bone using nanolubricant

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Frontiers of Mechanical Engineering 2023年第1期18卷 115-130页

作者： Yuying YANG Min YANG changhe LI Runze LI Zafar SAID Hafiz Muhammad ALI Shubham SHARMA School of Mechanical and Automotive Engineering Qingdao University of TechnologyQingdao 266520China College of Physics Qingdao UniversityQingdao 266071China Department of Biomedical Engineering University of Southern CaliforniaLos AngelesCA 90089USA Department of Sustainable and Renewable Energy Engineering University of SharjahSharjah 27272United Arab Emirates Mechanical Engineering Department King Fahd University of Petroleum and MineralsDhahran 31261Saudi Arabia Department of Mechanical Engineering IK Gujral Punjab Technical UniversityJalandhar 144603India

Bone grinding is an essential and vital procedure in most surgical operations.Currently,the insufficient cooling capacity of dry grinding,poor visibility of drip irrigation surgery area,and large grinding force leading to high grinding temperature are the technical bottlenecks of micro-grinding.A new micro-grinding process called ultrasonic vibration-assisted nanoparticle jet mist cooling(U-NJMC)is innovatively proposed to solve the technical problem.It combines the advantages of ultrasonic vibration(UV)and nanoparticle jet mist cooling(NJMC).Notwithstanding,the combined effect of multi parameter collaborative of U-NJMC on cooling has not been investigated.The grinding force,friction coefficient,specific grinding energy,and grinding temperature under dry,drip irrigation,UV,minimum quantity lubrication(MQL),NJMC,and U-NJMC micro-grinding were compared and analyzed.Results showed that the minimum normal grinding force and tangential grinding force of U-NJMC micro-grinding were 1.39 and 0.32 N,which were 75.1%and 82.9%less than those in dry grinding,respectively.The minimum friction coefficient and specific grinding energy were achieved using U-NJMC.Compared with dry,drip,UV,MQL,and NJMC grinding,the friction coefficient of U-NJMC was decreased by 31.3%,17.0%,19.0%,9.8%,and 12.5%,respectively,and the specific grinding energy was decreased by 83.0%,72.7%,77.8%,52.3%,and 64.7%,respectively.Compared with UV or NJMC alone,the grinding temperature of U-NJMC was decreased by 33.5%and 10.0%,respectively.These results showed that U-NJMC provides a novel approach for clinical surgical micro-grinding of biological bone.

关键词： micro-grinding biological bone ultrasonic vibration(UV) nanoparticle jet mist cooling(NJMC) grinding force grinding temperature

Crop production changes and the impact of Grain for Green program in the Loess Plateau of China

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Journal of Arid Land 2020年第1期12卷 18-28页

作者： LYU changhe XU Zhiyuan Key Laboratory of Land Surface Pattern and Simulation Institute of Geographic Sciences and Natural Resources ResearchChinese Academy of SciencesBeijing 100101China College of Resources and Environment University of Chinese Academy of SciencesBeijing 100049China Institute of Rural Development Zhejiang Academy of Agricultural SciencesHangzhou 310021China

Since the Grain for Green(GFG)program was implemented in 1999,most steeply sloping farmlands in the Loess Plateau of China have been returned to forestland and grassland.To understand its impact on the food production,this study analyzed the spatiotemporal changes of food crop production(FCP)in the plateau and quantified the contribution of sown area and yield changes to the total FCP during 1998–2014 using factor decomposition models,and then discussed the impact of GFG program on the FCP based on literature data.With the implementation of GFG program,total sown area in the Loess Plateau quickly deceased by 17.3%from 1998 to 2003,and then gradually restored to 1.03×107 hm2 in 2010.Thereafter,it slightly decreased to 1.02×107 hm2(94.6%of the area in 1998)in 2014.By contrast,total FCP generally showed an apparent growth trend,averagely increased by 1.71%per year in the whole plateau during 1998–2014.This increase was jointly contributed by the improved yield of individual crops,and the adjustment of cropping structure,i.e.,the expansion of high yield maize crop.The factor decomposition analysis results indicate that the sown area shrinkage only reduced the growth rate of total FCP by 0.29%per year during 1998–2014,although a significant impact was found for the early stage of 1999–2003.The results suggest that the implementation of GFG program would not induce an obvious risk of the food security.Therefore,it is suggested that the GFG program should be set as a long-term strategic policy,by not only supporting the conversion of slope farmlands,but also helping local farmers to seek sustainable ways of land use to improve the income and livelihood.It can be combined with the poverty eradication program,to simultaneously achieve the national goals of ecological civilization building and the livelihood improvement of rural people in the Loess Plateau.Considering rainfall limitation,the conversion of slope farmlands should be prioritized to grasslands.

关键词： spatiotemporal change farmland conversion hilly region factor decomposition semi-arid regions

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新疆大豆主要种植品种与排种器适配情况探究

新疆农机化 2024年第2期 8-10,28页

作者：白志业杨豫新班婷刘奎牛长河新疆农业科学院农业机械化研究所新疆乌鲁木齐830091

大豆是我国重要的经济作物,在我国农业生产中占有重要地位。目前大豆品种繁多,形状尺寸多样且差异较大,大豆排种器结构单一、尺寸固定,同一排种器播种不同大豆品种适应性较差。本文收集并测量新疆主栽大豆品种三轴尺寸,通过查阅大豆排... 详细信息

大豆是我国重要的经济作物,在我国农业生产中占有重要地位。目前大豆品种繁多,形状尺寸多样且差异较大,大豆排种器结构单一、尺寸固定,同一排种器播种不同大豆品种适应性较差。本文收集并测量新疆主栽大豆品种三轴尺寸,通过查阅大豆排种器相关文献,总结大豆排种器研究现状,分析大豆与现有排种器适配情况,对新疆主栽大豆播种机械化发展做出展望,为未来大豆播种机具创新发展提供参考。

关键词：大豆品种大豆排种器适配

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基于协同过滤的产教一体化平台设计与实现

现代计算机 2024年第3期30卷 107-111页

作者：韩家成何琳曾莉宁王长赫李吉祥北京信息科技大学计算机学院北京102206

当今社会上存在教育资源不平衡的现象,特别是在职业教育、就业学习等方面,所以基于协同过滤开发了“e习堂”产教一体化平台,一个集促进就业、教育学习功能于一体的教育公益平台。使用HTML5、CSS3、JavaScrapt搭建平台前端,使用Tomcat、J... 详细信息

当今社会上存在教育资源不平衡的现象,特别是在职业教育、就业学习等方面,所以基于协同过滤开发了“e习堂”产教一体化平台,一个集促进就业、教育学习功能于一体的教育公益平台。使用HTML5、CSS3、JavaScrapt搭建平台前端,使用Tomcat、JDBC、Servlet、Druid、MySQL搭建平台后端。利用Java实现登录、查看、推荐等平台功能。平台通过协同过滤将企业招聘版块和网课、图书学习资源相互关联,形成产学的闭环,均衡配置教学资源,明确学习的导向性和目的性,激发学生的内生活力。

关键词： UserCF 产教一体化平台 JavaWeb

6个不同品种荔枝果肉内生细菌群落多样性的高通量测序分析

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广东农业科学 2024年第2期51卷 29-38页

作者：史发超蔡长河严倩姜永华刘海伦文英杰欧良喜陈洁珍广东省农业科学院果树研究所/农业农村部南亚热带果树生物学与遗传资源利用重点实验室/广东省热带亚热带果树研究重点实验室广东广州510640

【目的】内生菌在植物生长发育中发挥重要作用,分析不同品种荔枝果肉内生细菌群落结构及多样性,挖掘和利用潜在荔枝内生菌种资源,为进一步研究荔枝与内生菌互作关系提供参考依据。【方法】以6个不同品种荔枝的果肉组织为材料,PCR扩增16S... 详细信息

【目的】内生菌在植物生长发育中发挥重要作用,分析不同品种荔枝果肉内生细菌群落结构及多样性,挖掘和利用潜在荔枝内生菌种资源,为进一步研究荔枝与内生菌互作关系提供参考依据。【方法】以6个不同品种荔枝的果肉组织为材料,PCR扩增16SrDNA的V3~V4区,利用MiSeq高通量测序技术分析果肉组织内生细菌在门、科、属和种分类水平上的群落组成及优势菌群,结合Alpha多样性分析评估内生细菌群落多样性。【结果】对6个品种荔枝果肉内生细菌16S rDNA的V3~V4区进行扩增,共获得2139086条序列,其平均长度为376 bp。不同品种荔枝果肉内生细菌群落在相对丰度和多样性上无显著差异。在门分类水平,变形菌门为主要优势细菌门类,其次为放线菌门。在科、属和种分类水平上,不同品种荔枝内生菌群落结构相似,但相对丰度占比不同。差异菌群分析结果显示,假单胞菌属(Pseudomonas)、果胶杆菌属(Pectobacterium)、苍白杆菌属(Ochrobactrum)和迪基氏菌属(Dickeya)在优良品种‘鹅蛋荔’‘糯米糍’和‘观音绿’中显著富集,根瘤菌属(Bradyrhizobium)和变形菌属(Snodgrassella)只在‘鹅蛋荔’中富集。根据菌群相对丰度进行聚类分析,‘观音绿’‘糯米糍’和‘鹅蛋荔’的相似性更高。Alpha多样性分析结果表明,6种荔枝果肉内生菌群仅在丰度和多样性上存在差异,但未达到显著水平。【结论】该研究首次分析了6个不同品种荔枝果肉内生细菌的群落结构,并在优良荔枝品种中发现特有的微生物类群富集现象,可为后续提升荔枝品质、开发利用内生菌提供理论依据和重要参考。

关键词：荔枝果肉内生细菌群落结构微生物多样性优势菌群高通量测序

Urban land expansion and arable land loss of the major cities in China in the 1990s

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Science China Earth Sciences 2005年第9期48卷 1492-1500页

作者： TAN Minghong LI Xiubin LU changhe Institute of Geographic Sciences and Natural Resources Research Chinese Academy of Sciences Beijing 100101 China Institute of Geographic Sciences and Natural Resources Research Chinese Academy of Sciences Beijing 100101 China Institute of Geographic Sciences and Natural Resources Research Chinese Academy of Sciences Beijing 100101 China

Based on the land-use data in 1990 and 2000, determined by interpreting Landsat Thematic Mapper (TM) imagery, this paper defines the extent of urban construction land, and extracts patches of urban construction land of 145 cities with the largest areas in 1990 and arable land patches around these cities. With these data, this paper analyzes the characteristics of ur- ban construction land expansion and the consequent arable land loss in East, Middle and West China, and further identifies the social, economic and spatial factors of the urban land use changes, using GIS (Geographical Information System) and multivariate regression approaches. The results show that total urban land of the 145 cities expanded by 39.8%, with about 70% of the new urban land converted from arable land in the 1990s. The urban land expansion varied among the three regions, with a value of 43.0% in the East, 33.1% in the West (33.1%) and 17.8% in the Middle. Moreover, mean urban construction land per capita increased by10.7% in the East, but it decreased by 7.7% in the Middle, 1.4% in the West. Statistical analysis indicated that total wages of staff and workers could best explain the differences of urban land expansion.

关键词： China, urban construction land expansion, arable land loss, regional difference, neighboring index [I(i)].