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A Remote Driving Path Planning Scheme Based on 5G QoS Prediction

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A Remote Driving Path Planning Scheme Based on 5G QoS Predic...

Research on Heavy Load Logistics Control System

第35届中国过程控制会议

作者： daqian liu Huajun Huang Yuntao Shi Xiang Yin School of Electrical and Control Engineering North China University of Technology

Vehicle-to-everything(V2X) services are now a reality due to the rapid development of 5G networks and autonomous driving technologies. Compared to the consumer internet, the V2X often faces tough network performance requirements,including metrics such as throughput and end-to-end delay. Therefore, predicting the Quality of service(QoS) of V2X for vehicle users in a timely manner and responding quickly is crucial. Although QoS prediction techniques are mature, their application in remote driving use cases is still being explored. This paper proposes a path planning scheme for remote driving under 5G network coverage. The scheme combines path planning algorithms and QoS prediction techniques to select the most suitable traffic path for the current situation. The study evaluates the scheme based on 3GPP standard scenarios and demonstrates its feasibility and practicality. The evaluation results indicate that the scheme is able to accurately predict predefined QoS metrics and based on these metrics select the optimal traffic path for the vehicle's current situation.

关键词： 5G V2X QoS prediction Traffic path planning

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Research on Heavy Load Logistics Control System

面向动态目标搜索与打击的空地协同自主任务分配方法

第35届中国过程控制会议

作者： Fuping Dou Bin Zuo Jian Xu daqian liu Xiang Yin School of Electrical and Control Engineering North China University of Technology

The research objective of this paper is to develop a steel coil transportation control system in the metallurgical *** system applies PLC control technology, motion control technology, wireless communication technology, and information scheduling planning algorithm technology. The traditional steel coil transportation control system is difficult to accurately locate the transportation vehicles of dozens of tons of goods, track the information of steel coils, and manage logistics scheduling. To address the aforementioned issues, this article designs and implements a heavy load logistics transportation control system. This well-designed control system has the characteristics of wide coverage area, high positioning accuracy of transport vehicles and intelligent scheduling of the whole process. Field operation results show that the control system can meet the requirements of end-to-end seamless cooperation and efficient and safe operation of each production process.

关键词： Control system Process control Motion control Heavy load logistics Intelligent scheduling

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系统工程与电子技术 2024年第7期46卷 2346-2358页

作者：费博雯包卫东刘大千朱晓敏国防科技大学系统工程学院湖南长沙410073

面向复杂城市环境中的运动目标搜索与打击任务,单域无人平台受视野范围和运动能力等限制,易出现目标遗漏和任务完成率低的问题。针对这些问题,提出一种面向动态目标搜索与打击的空地协同自主任务分配方法,通过结合无人机视野范围广以及... 详细信息

面向复杂城市环境中的运动目标搜索与打击任务,单域无人平台受视野范围和运动能力等限制,易出现目标遗漏和任务完成率低的问题。针对这些问题,提出一种面向动态目标搜索与打击的空地协同自主任务分配方法,通过结合无人机视野范围广以及无人车机动性强的特点,提升空地无人系统的任务执行效率和区域覆盖率。一方面,针对未知运动目标,提出一种基于数字信息素的目标搜索模型,以平台协同收益和区域覆盖率为优化指标,保证在尽可能短的时间周期内发现区域中的所有目标。另一方面,面向动态到达的打击任务,构建基于可行路径规划的任务分配模型,以平台能耗和任务完成时间为目标函数,在保证任务完成率的同时,提高空地协同系统的资源利用率。与现有方法相比,所提方法能够在最短的时间内发现所有目标,区域覆盖率达到55%以上,且资源利用率为84.4%。实验结果表明,所提方法具备较好的目标搜索和任务执行能力。

关键词：空地协同数字信息素目标搜索任务分配路径规划

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长白山地区乡村聚落空间格局及影响因素

水土保持研究 2024年第3期31卷 383-390,400页

作者：刘大千王丹许骏孙汉杰中国科学院东北地理与农业生态研究所长春130102 吉林工商学院旅游学院长春130507 长春工程学院长春130012 长白山历史文化与VR技术重构吉林省重点实验室长春130012

[目的]探究长白山地区乡村聚落空间分布特征和影响因素,理解近代大量移民背景下中高纬度山区乡村居民点空间格局的形成过程和机制。[方法]综合运用核密度分析、空间自相关分析、空间回归分析和地理探测器等方法,解析长白山地区乡村聚落... 详细信息

[目的]探究长白山地区乡村聚落空间分布特征和影响因素,理解近代大量移民背景下中高纬度山区乡村居民点空间格局的形成过程和机制。[方法]综合运用核密度分析、空间自相关分析、空间回归分析和地理探测器等方法,解析长白山地区乡村聚落的空间格局并揭示其影响因素。[结果]长白山地区的乡村聚落呈现出明显的集聚分布特征,存在东北和西南两个聚集区域;各类空间回归方法中,空间杜宾误差模型的拟合效果最佳,结果表明耕地资源和高程是影响长白山地区乡村聚落格局最重要的因素,且对于邻域居民点的布局存在“推拉”效应,潜在未知变量(如土壤质量、文化因素等)也是导致乡村聚落表现出空间自相关的因素;地理探测器分析的结果进一步证实了耕地资源和高程的重要性,同时也表明与县级以上城市、建制镇、主要交通线、主要河流的距离等区位因素以及地形坡度同样对乡村聚落分布有显著影响,且彼此间均呈现出交互增强的特点。[结论]主要由移民形成的中高纬度山区乡村聚落的空间格局是多因素综合作用的结果,其中耕地资源和高程的影响更为显著;空间回归杜宾(误差)模型能够同时探测自变量和因变量的空间自相关问题,在乡村聚落空间格局的研究中具有一定的适用性。

关键词：乡村聚落空间格局空间回归模型地理探测器长白山地区

Spatiotemporal Variations and Influencing Factors Analysis of PM_(2.5) Concentrations in Jilin Province,Northeast China

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Chinese Geographical Science 2018年第5期28卷 810-822页

作者： WEN Xin ZHANG Pingyu liu daqian Northeast Institute of Geography and Agroecology Chinese Academy of Sciences

High PM_(2.5) concentrations and frequent air pollution episodes during late autumn and winter in Jilin Province have attracted attention in recent years. To describe the spatial and temporal variations of PM_(2.5) concentrations and identify the decisive influencing factors, a large amount of continuous daily PM_(2.5) concentration data collected from 33 monitoring stations over 2-year period from 2015 to 2016 were analyzed. Meanwhile, the relationships were investigated between PM_(2.5) concentrations and the land cover, socioeconomic and meteorological factors from the macroscopic perspective using multiple linear regressions(MLR) approach. PM_(2.5) concentrations across Jilin Province averaged 49 μg/m^3, nearly 1.5 times of the Chinese annual average standard, and exhibited seasonal patterns with generally higher levels during late autumn and over the long winter than the other seasons. Jilin Province could be divided into three kinds of sub-regions according to 2-year average PM_(2.5) concentration of each city. Most of the spatial variation in PM_(2.5) levels could be explained by forest land area, cultivated land area, urban greening rate, coal consumption and soot emissions of cement manufacturing. In addition, daily PM_(2.5) concentrations had negative correlation with daily precipitation and positive correlation with air pressure for each city, and the spread and dilution effect of wind speed on PM_(2.5) was more obvious at mountainous area in Jilin Province. These results indicated that coal consumption, cement manufacturing and straw burning were the most important emission sources for the high PM_(2.5) levels, while afforestation and urban greening could mitigate particulate air pollution. Meanwhile, the individual meteorological factors such as precipitation, air pressure, wind speed and temperature could influence local PM_(2.5) concentration indirectly.

关键词： particulate matter PM2.5 spatial variation temporal variation Jilin Province

A New Approach to Measurement of Regional Inequality in Particular Directions

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Chinese Geographical Science 2012年第6期22卷 705-717页

作者： WANG Yang FANG Chuanglin XIU Chunliang liu daqian Institute of Geographic Sciences and Natural Resources Research Chinese Academy of Sciences Beijing 100101 China Graduate University of Chinese Academy of Sciences Beijing 100049 China School of Urban and Environmental Sciences Northeast Normal University Changchun 130024 China

Regional inequality is a core issue in geography,and it can be measured by several approaches and ***,the global inequality measures can not reflect regional characteristics in terms of spatiality and non-mobility,as well as correctly explore regional inequality in particular *** conventional between-group inequality indexes can measure the inequality in particular directions,they can not reflect the reversals of regional patterns and changes of within-group ***,we set forth a new approach to measure regional inequality in particular directions,which is applicable to geographic *** on grouping,we established a new index to measure regional inequality in particular directions named Particular Direction Inequality index(PDI index),which is comprised of between-group inequality of all data and between-group average *** can reflect regional spatiality and non-mobility,judge the main direction of regional inequality,and capture the changes and reversals of regional *** used the PDI index to measure the changes of regional inequality from 1952 to 2009 in *** results show that:1) the main direction of China's regional inequality was between coastal areas and inland areas;the increasing extent of inequality between coastal areas and inland areas was higher than the global inequality;2) the PDI index can measure the between-region average gap,and is more sensitive to evolution of within-region patterns;3) the inequality between the northern China and the southern China has been decreasing from 1952 to 2009 and was reversed in 1994 and 1995.

关键词： regional inequality inequality indexes PDI index particular directions China

Spatial Patterns of Car Sales and Their Socio-economic Attributes in China

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Chinese Geographical Science 2017年第5期27卷 684-696页

作者： liu daqian LO Kevin SONG Wei XIE Chunyan Northeast Institute of Geography and Agroecology Chinese Academy of SciencesChangchun 130102China Department of Geography Hong Kong Baptist UniversityHong Kong 999077China Department of Geography and Geosciences University of LouisvilleLouisville KY 40292USA FAW-Volkswagen Automotive Company Ltd. Changehun 130061China

Using data from the Economic Advisory Center of the State Information Center(SIC), we examined the spatial patterns of car sales in China at the prefectural level in 2012. We first analyzed the spatial distributions of car sales of different kinds of automakers(foreign automakers, Sino-foreign joint automakers, and Chinese automakers), and then identified spatial clusters using the local Moran's indexes. Location quotient analysis was applied to examine the relative advantage of each type of automaker in the local markets. To explain the variations of car sales across cities, we collected several socioeconomic variables and conducted regression analyses. Further, factor analysis was used to extract independent variables to avoid the problem of multicollinearity. By incorporating a spatial lag or spatial error in the models, we calibrated our spatial regression models to address the spatial dependence problem. The analytical results show that car sales varied significantly across cities in China, and most of the cities with higher car sales were the developed cities. Different automakers exhibit diverse spatial patterns in terms of car sales volume, spatial clusters, and location quotients. The scale and incomes factor were extracted and verified as the two most significant and positive factors that shape the spatial distributions of car sales, and together with the spatial effect, explained most of the variations of car sales across cities.

关键词： car sales spatial clusters Location Quotient socio-economic attributes China

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吉林油田典型集输接转站场提质提效研究

油气田地面工程 2024年第7期43卷 14-21页

作者：刘大千李晓平周海莲赵子慧宫敬中国石油大学(北京) 中国石油天然气股份有限公司吉林油田分公司(勘察设计院)

吉林油田地面工程系统中接转站存在高能耗问题。通过分析接转站的主要工作流程,计算出每个流程中用能环节的能耗占比,找出接转站产生高能耗的主要原因为加热炉的能耗过高。对加热炉出口温度进行调整,降低加热炉能耗,最终达到接转站能耗... 详细信息

吉林油田地面工程系统中接转站存在高能耗问题。通过分析接转站的主要工作流程,计算出每个流程中用能环节的能耗占比,找出接转站产生高能耗的主要原因为加热炉的能耗过高。对加热炉出口温度进行调整,降低加热炉能耗,最终达到接转站能耗降至最低的效果。优化计算结果表明,当海118接转站冬季、夏季外输流程加热炉出口温度分别为43.8℃和37.2℃,冬季、夏季掺输流程加热炉出口温度分别为51℃和44℃时,接转站全年能耗最低,可减少使用碳307 t/a;当新民6接转站冬季、夏季外输流程加热炉出口温度分别为44.4℃和44.2℃,冬季、夏季掺输流程加热炉出口温度分别为54.5℃和49.5℃时,接转站全年能耗最低,可减少使用碳375 t/a;当让47接转站冬季、夏季外输流程加热炉出口温度分别为47.9℃和46.6℃,冬季、夏季掺输流程加热炉出口温度分别为57℃和56℃时,接转站全年能耗最低,可减少使用碳333 t/a。

关键词：接转站加热炉出口温度能耗占比外输流程掺输流程

Efficient hydrogenolysis of fructose to 1,2-propanediol over bifunctional Ru-WO_(x)-MgO_(y) catalysts under mild reaction conditions via enhancing the chemoselective cleavage of C-C bonds

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Journal of Energy Chemistry 2024年第5期92卷 311-321页

作者： Shuang Luo Tie Shu Min Mao Haijie Yu Yuxin Zheng daqian Ding Lingmei liu Kexin Yao Jianjian Wang School of Chemistry and Chemical Engineering State Key Laboratory of Coal Mine Disaster Dynamics and ControlInstitute of Advanced Interdisciplinary StudiesMulti-scale Porous Materials CenterChongqing UniversityChongqing 401331China Key Laboratory for Efficient Conversion and Circular Economy of Coal Chemical Engineering CollegeInner Mongolia University of TechnologyHohhot 010051Inner MongoliaChina

Selective conversion of fructose to 1,2-propanediol(1,2-PDO)is considered as a sustainable and cost-effective alternative to petroleum-based processes,however,this approach still faces challenges associated with low efficiency and harsh reaction ***,we have successfully synthesized a novel bifunctional Ru-WO_(x)-MgO_(y) catalyst through a facile'one-pot'solvothermal ***,this catalyst exhibits exceptional catalytic performances in the conversion of fructose to 1,2-PDO under mild reaction *** yield of 1,2-PDO is up to 56.2%at 140°C for 4 h under an ultra-low hydrogen pressure of only 0.2 MPa,surpassing the reported results in recent literature(below 51%).Comprehensive characterizations and density functional theory(DFT)calculations reveal that the presence of oxygen vacancies in the Ru-WO_(x)-MgO_(y) catalyst,serving as active acidic sites,facilitates the chemoselective cleavage of C-C bonds in fructose,which leads to the generation of active intermediates and ultimately resulted in the high yield of 1,2-PDO.

关键词： Biomass Fructose 1,2-Propanediol Retroaldol condensation Heterogenous catalysis