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改进混合粒子群算法求解带时间窗的无人机与车辆协同路径调度问题

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计算机应用研究 2024年第8期41卷 2336-2342页

作者：叶立威吴钧皓戚远航罗浩宇黄戈文王福杰电子科技大学中山学院计算机学院广东中山528402 广东工业大学自动化学院广州510006 嘉应学院信息网络中心广东梅州514015 东莞理工学院卓越工程师学院广东东莞523808

为提高物流配送效率,考虑时间窗、无人机换电以及无人机多点连续配送等因素,提出了一种带时间窗的车辆与无人机协同配送问题,并设计一种带局部搜索的混合粒子群算法进行求解。该算法以混合粒子群算法为核心,通过构建高效的编解码策略实... 详细信息

为提高物流配送效率,考虑时间窗、无人机换电以及无人机多点连续配送等因素,提出了一种带时间窗的车辆与无人机协同配送问题,并设计一种带局部搜索的混合粒子群算法进行求解。该算法以混合粒子群算法为核心,通过构建高效的编解码策略实现了问题解空间到算法搜索空间的转换。进一步,该算法融合单点插入策略、车辆更换策略、无人机更换策略组成局部搜索策略,以此提高算法寻优能力。实验结果表明:所提模型比纯车辆配送的模型效率更高,节省了3..51%的成本;所提算法优于四种对比算法,优化率最高达到82.08%。

关键词：无人机车辆调度粒子群时间窗车辆路径问题

变厚截面材料激光穿透焊接自适应功率控制研究

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金属加工（热加工） 2024年第2期 23-29,33页

作者：周麒张哲豪李栋梁罗耀恩赵育泽陈聪曾宏玉袁方湖南科技大学难加工材料高效精密加工湖南省重点实验室湖南湘潭411201 湖南科技大学未来技术学院湖南湘潭411201 湖南泰嘉新材料科技股份有限公司湖南长沙410200 湖南大学智能激光制造湖南省重点实验室湖南长沙410082

激光焊接变厚截面板是实现汽车轻量化的有效举措,但在激光焊接过程中,因工艺不稳定易导致焊缝熔透状态不一致,工件焊接质量较差。由于激光功率易于控制且对熔深影响显著,因此从变厚截面板激光焊接过程中的功率控制需求入手,设计了功率... 详细信息

激光焊接变厚截面板是实现汽车轻量化的有效举措,但在激光焊接过程中,因工艺不稳定易导致焊缝熔透状态不一致,工件焊接质量较差。由于激光功率易于控制且对熔深影响显著,因此从变厚截面板激光焊接过程中的功率控制需求入手,设计了功率控制软硬件系统,完成了功率控制平台的搭建;采用卷积神经网络对同轴图像采集系统获取的小孔穿透孔图像进行分类,依据穿透孔面积分为未熔透、适度熔透和过熔透,采用PID控制系统根据分类结果编码实时改变焊接功率以获得适度熔透状态;通过采用变截面板进行激光焊接功率自适应调控试验,获得了背部余高均匀的焊缝,验证了自适应功率监测和控制算法的有效性。

关键词：激光焊接变厚截面材料熔透状态自适应功率控制

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基于声学宽带扩频信号的抗多径测距技术研究

海洋测绘 2024年第1期44卷 26-30页

作者：罗宇王浩辛明真程梦迪张世照亓家宝山东科技大学测绘与空间信息学院山东青岛266590 自然资源部海洋测绘重点实验室山东青岛266590

为研究宽带扩频信号在复杂水声信道下的测距精度,提高水声定位系统的抗多径性能,以BELLHOP模型的多径干扰冲激响应作为水声信道环境基础,通过构造不同传播距离、海洋环境特征的多径水声信道,对宽带扩频编码进行同步相关测距仿真;提出一... 详细信息

为研究宽带扩频信号在复杂水声信道下的测距精度,提高水声定位系统的抗多径性能,以BELLHOP模型的多径干扰冲激响应作为水声信道环境基础,通过构造不同传播距离、海洋环境特征的多径水声信道,对宽带扩频编码进行同步相关测距仿真;提出一种基于宽带扩频信号载波域同步的抗多径测距方法,利用载波携带的宽带特征信息进行相关同步以提高理论测距精度。实验结果表明:在有直达声且不考虑声线弯曲条件下,浅海多径信道条件测距精度可达厘米级,中深水信道维持分米级测距精度,较基带同步方法的抗干扰性能有所提升,基于宽带扩频信号载波域同步的抗多径测距方法,能够为声学定位系统的高性能测距技术提供理论依据。

关键词：水声定位 BELLHOP模型时延测距抗多径宽带扩频

Identification of genes involved in regulating MnSOD2.production and root colonization in Bacillus cereus 905

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Journal of Integrative Agriculture 2021年第6期20卷 1570-1584页

作者： GAO Tan-tan DING Ming-zheng LI Yan zeng qing-chao WANG qi Key Laboratory for Northern Urban Agriculture of Ministry of Agriculture and Rural Affairs Beijing University of AgricultureBeijing 102206P.R.China Department of Plant Pathology College of Plant ProtectionChina Agricultural UniversityBeijing 100193P.R.China

sodA2.encoding manganese-containing superoxide dismutase(MnSOD2.in Bacillus cereus 905 plays an essential role in antioxidative stress,nutrition utilization,rhizosphere and phyllosphere ***,the genes involved in regulating the sod A2.expression have not been clearly elucidated in *** this study,a genome-wide random insertion mutagenesis was constructed by using transposon TnYLB-1 to identify novel genes regulating the sodA2.*** mutants that changed the sodA2.expression at both m RNA and protein levels were finally *** analysis and BLAST data showed that the genes disrupted by TnYLB-1 in *** 905 shared high conservations with those in the *** type strain,ATCC *** genes encode heat-inducible transcription repressor,chloride channel protein,recombinase A,ferrous iron transport protein,nucleoside diphosphate kinase,and histidine ***,we also provided the evidence that the genes regulating the sodA2.expression could influence colonization ability of *** 905 on wheat ***,those genes downregulating the sodA2.expression significantly reduced bacterial colonization on wheat roots,and mutants with increased MnSOD2.activities could enhance bacterial population densities on wheat roots to a certain *** work provided information that multiple genes are involved in MnSOD2.production and wheat root *** molecular regulatory pathways through which these genes modulate the sod A2.expression and root colonization need to be investigated extensively in the future.

关键词： Bacillus cereus sod A2 TnYLB-1 transposon colonization

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设施温室物联网智能测控系统研究

山东农业大学学报（自然科学版） 2024年第4期55卷 633-643页

作者：章子文梁思程张洪奇吴勇张大磊柳平增山东农业大学信息科学与工程学院山东泰安271018 农业农村部黄淮海智慧农业技术重点实验室山东泰安271018 山东农业大学农业大数据研究中心山东泰安271018 泰山科技学院山东泰安271038 山东勇冠农业科技发展有限公司山东菏泽274900

针对温室环境调控中手动控制和阈值条件调控存在调控精度低、参数超调严重等问题,以设施番茄温室为例,研究提出一种基于环境预测的精准调控策略。首先,构建专用物联网“六域”架构,采用MSP43.F543.A作为主控模块,设计感知、通信等功能... 详细信息

针对温室环境调控中手动控制和阈值条件调控存在调控精度低、参数超调严重等问题,以设施番茄温室为例,研究提出一种基于环境预测的精准调控策略。首先,构建专用物联网“六域”架构,采用MSP43.F543.A作为主控模块,设计感知、通信等功能模块。其次,构建SSA-LSTM预测模型实现对温室环境的精准预测,并根据模型预测结果确定环境调控策略,通过PSO-PID控制模型实现对温室风口电机的精准控制。实验结果表明,相较于传统LSTM模型,SSA-LSTM预测模型的MAE降低58.52.,MAPE降低61.68%,RMSE降低63.84%。同时,相较于传统PID模型,PSO-PID控制模型的超调量降低89.99%,调节时间降低59.85%。系统经过实地部署验证,在保持种植品种和农事管理操作一致的情形下,智能调控的温室产量相较于传统温室提升约8.5%,证明了系统的有效实用性。

关键词：温度预测控制模型农业物联网温室环境

维普期刊数据库博看期刊

Theory and application of stability for stochastic reaction diffusion systems

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science in china(Series F) 2008年第2期51卷 158-170页

作者： luo qi DENG Feiqi MAO XueRong BAO JunDong ZHANG YuTian college of information and {2. Nanjing University of Information Science & Technology Nanjing 210044 China college of Automation South China University of Technology Guangzhou 410640 China Department of Statistics and Modelling science University of-Strathc/yde Glasgow G1 IXH Scotland UK Coilege of Mathematics science Inner Mongolia Normal'University Huhhot 010000 China college of Mathematics and Physics Nanjing University of Information Science & Technology Nanjing 210044 China

So far, the Lyapunov direct method is still the most effective technique in the study of stability for ordinary differential equations and stochastic differential equations. Due to the shortage of the corresponding It6 formula, this useful method has not been popularized in stochastic partial differential equations. The aim of this work is to try to extend the Lyapunov direct method to the It6 stochastic reaction diffusion systems and to establish the corresponding Lyapunov stability theory, including stability in probablity, asymptotic stability in probablity, and exponential stability in mean square. As the application of the obtained theorems, this paper addresses the stability of the Hopfield neural network and points out that the main results ob- tained by Holden Helge and liao xiaoxin et al. can be all regarded as the corollaries of the theorems presented in this paper.

关键词： stochastic reaction diffusion system stability in probability asymptotic stability in probability exponentialstability in mean square

Assessing the influence of highway and high-speed railway construction on local climate using Landsat images in karst areas

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Journal of Mountain science 2019年第7期16卷 1584-1597页

作者： ZHOU Hua luo Yang DING Fang-jun LIN qi-nan Guizhou Academy of Forestry No.382 Fuyuan South Road Nanming DistrictGuiyang 550000China Beijing Forestry University Forestry CollegeN0.35 Tsinghua East RoadHaidian DistrictBeijing 100083China

Large-scale transportation infrastructure construction in ecologically vulnerable areas such as the karst region of Southwest china requires estimation method for better project *** research was carried out on a four-lane highway(the Guilin-Guiyang highway,G76)and a two-lane highspeed railway(the Guilin-Guiyang high-speed railway,GGHSR)in karst areas in Guizhou and Guangxi *** highway and high-speed railway were constructed in the 2.10 s and covered by Landsat images whose multispectral {2. could be used for research *** this study,the severity of the impact and the CO2.emissions from the G76 and GGHSR construction were *** images and field meteorological measurements were applied to calculate the surface functional parameters(surface temperature and surface wetness)and heat fluxes(latent,sensible and ground heat flux)before and during the highway and high-speed railway construction;the amount of CO2.emissions during the G76 and GGHSR construction were determined by using budget sheets,which record the detail consumptions of materials and *** results showed that the decrease of water evaporation from the highway and high-speed railway construction can reach up to 2..4 m3.and 2..1 m3.per kilometer,which corresponds to an average decrease in the vegetation cooling effect of 18.0 MWh per day per highway kilometer and 13.7 MWh per day per high-speed railway kilometer,*** the meantime,the average CO2.emission densities from the G76 and GGHSR construction can reach up to 2.813.7 and 3.92..1 t/km,*** study implied that extensive line constructions have a significant impact on the local climate and the energy balance,and it is evident that selecting and planting appropriate plant species can compensate for the adverse effects of line constructions in karst mountain regions.

关键词： Highway construction High-speed railway construction Heat flux balance Surface temperature Landsat Vegetation cooling effect CO2 emission

Effects of seasonal variation on soil microbial community structure and enzyme activity in a Masson pine forest in Southwest china

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Journal of Mountain science 2020年第6期17卷 1398-1409页

作者： luo Song-ping HE Bing-hui zeng {2.ng-ping LI Nan-jie YANG Lei college of Resources and Environment Southwest UniversityChongqing 400715China technology Consulting Research Center of Soil and Water Conservation of Guizhou Province Guiyang 550002China Chongqing Engineering technology Research Center for {2. Management in Development Chongqing Technology and Business UniversityChongqing 400067China State Key Laboratory of Urban and Regional Ecology Research Center for Eco-Environmental SciencesChinese Academy of SciencesBeijing 100085China

Soil microbial communities and enzyme activities play key roles in soil *** are sensitive to changes in environmental factors,including seasonal temperature,precipitation variations and soil *** understand the interactive mechanisms of seasonal changes that affect soil microbial communities and enzyme activities in a subtropical masson pine(Pinus massoniana)forest,we investigated the soil microbial community structure and enzyme activities to identify the effect of seasonal changes on the soil microbial community for two years in Jinyun Mountain National Nature Reserve,Chongqing,*** soil microbial community structure was investigated using phospholipid fatty acids(PLFAs).The results indicated that a total of 3. different PLFAs were identified,and 16:0 was found in the highest proportions in the four seasons,moreover,the total PLFAs abundance were highest in spring and lowest in *** and actinomycetes were the dominant types in the study *** changes also had a significant(P<0.05)influence on the soil enzyme *** maximum and minimum values of the invertase and catalase activities were observed in autumn and winter,***,the maximum and minimum values of the urease and phosphatase acid enzymatic activities were found in spring and winter,*** correspondence analysis(CCA)analysis revealed that the seasonal shifts in soil community composition and enzyme activities were relatively more sensitive to soil moisture and temperature,but the microbial community structure and enzyme activity were not correlated with soil pH in the study *** study highlights how the seasonal variations affect the microbial community and function(enzyme activity)to better understand and predict microbial responses to future climate regimes in subtropical area.

关键词： PLFA analysis Soil microorganisms soil enzymes Seasonal shifts Soil moisture Soil temperature

用于紫外线成像和无线报警的水凝胶基可伸缩、高稳定性和高性能的光电传感器

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science china Materials 2024年第6期67卷 1926-1937页

作者：洪杰钊姚帝杰王浩丁琼玲罗艺冰于家豪张鹤曾令兴杨柏儒王冰陶凯吴进 State Key Laboratory of Optoelectronic Materials and Technologies and Guangdong Province Key Laboratory of Display Material and technology School of Electronics and Information TechnologySun Yat-sen UniversityGuangzhou 510275China Ministry of Education Key Laboratory of Micro and Nano Systems for Aerospace Northwestern Polytechnical UniversityXi’an 710072China Research&Development Institute of Northwestern Polytechnical University in Shenzhen Northwestern Polytechnical UniversityShenzhen 518063China State Key Laboratory of Transducer technology Shanghai 200050China Guangdong Provincial Key Laboratory of Technique and Equipment for Macromolecular Advanced Manufacturing National Engineering Research Center of Novel Equipment for Polymer ProcessingKey Laboratory of Polymer Processing Engineering(SCUT)Ministry of EducationSouth China University of TechnologyGuangzhou 510641China Engineering Research Center of Polymer Green Recycling of Ministry of Education College of Environment and ResourcesFujian Normal UniversityFuzhou 350007China State Key Laboratory of Polymer Materials Engineering Sichuan UniversityChengdu 610065China

柔性可穿戴的紫外线探测器在个体紫外线暴露监测、智能仿生眼和军事领域受到广泛关注.然而,传统不可拉伸的材料和器件结构设计限制了设备在可动态变形的人体皮肤和非平面表面上的精确监测应用和稳定附着.在本研究中,我们提出了基于氧化... 详细信息

柔性可穿戴的紫外线探测器在个体紫外线暴露监测、智能仿生眼和军事领域受到广泛关注.然而,传统不可拉伸的材料和器件结构设计限制了设备在可动态变形的人体皮肤和非平面表面上的精确监测应用和稳定附着.在本研究中,我们提出了基于氧化铜/碳-水凝胶-氧化锌/碳的新型应变隔离异质结构的本征可拉伸(拉伸应变或弯曲高达150%)紫外线探测器,该探测器具有高灵敏度(开/关比为2.00%)、高稳定性(大于4000次循环),以及快速响应和恢复时间(分别为1.5和4 s).值得注意的是,该探测器通过水凝胶桥在氧化铜/碳和氧化锌/碳电极之间引入的p-n结能带结构,以及离子导电水凝胶中I^(-)/I_(3.^(-)的电化学反应机制,显著提高了其载流子效率和紫外线响应强度.本文通过集成传感器与所设计的电路板,进一步开发了一种无线紫外线报警系统,用于紫外线强度超标警报.此外,本文还设计了一种光电传感器阵列,并将其用作视网膜假体,以实现对环境紫外线强度的实时监测和成像.本文基于水凝胶基异质结构为开发可穿戴、可拉伸的光电紫外线传感器单元和成像阵列提供了一种新的可行方法.

关键词： flexible hydrogel sensors stretchable UV sensors UV imaging array optoelectronic sensors wireless alarm