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Research on a TOPSIS energy efficiency evaluation system for crude oil gathering and transportation systems based on a GA-BP neural network

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Petroleum Science 2024年第1期21卷 621-640页

作者： Xue-Qiang Zhang Qing-Lin Cheng wei Sun Yi Zhao Zhi-min Li Key Lab of ministry of Education for Enhancing the Oil and Gas Recovery Ratio Northeast Petroleum UniversityDaqing163318HeilongjiangChina China Petroleum Pipeline Material and Equipment Co. LtdLangfang065000HebeiChina Research Institute of Petroleum Engineering and Technology Sinopec Northwest Oilfield CompanyUrumqi830011XinjiangChina

As the main link of ground engineering,crude oil gathering and transportation systems require huge energy consumption and complex *** is necessary to establish an energy efficiency evaluation system for crude oil gathering and transportation systems and identify the energy efficiency *** this paper,the energy efficiency evaluation system of the crude oil gathering and transportation system in an oilfield in western China is *** with the big data analysis method,the GA-BP neural network is used to establish the energy efficiency index prediction model for crude oil gathering and transportation *** comprehensive energy consumption,gas consumption,power consumption,energy utilization rate,heat utilization rate,and power utilization rate of crude oil gathering and transportation systems are *** the efficiency and unit consumption index of the crude oil gathering and transportation system,the energy efficiency evaluation system of the crude oil gathering and transportation system is established based on a game theory combined weighting method and TOPSIS evaluation method,and the subjective weight is determined by the triangular fuzzy analytic hierarchy *** entropy weight method determines the objective weight,and the combined weight of game theory combines subjectivity with objectivity to comprehensively evaluate the comprehensive energy efficiency of crude oil gathering and transportation systems and their ***,the weak links in energy utilization are identified,and energy conservation and consumption reduction are *** above research provides technical support for the green,efficient and intelligent development of crude oil gathering and transportation systems.

关键词： Crude oil gathering and transportation system GA-BP neural network Energy efficiency evaluation TOPSIS evaluation method Energy saving and consumption reduction

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一般7R串联机器人标定的仿真与实验

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机器人 2006年第5期28卷 483-487,494页

作者：王品廖启征庄育锋魏世民北京邮电大学自动化学院北京100876

为了标定一般7R冗余度串联机器人的所有几何参数,提出了一种实效的算法.首先,使用D-H矩阵对机器人建立了运动学模型和几何参数识别模型,对雅可比矩阵进行奇异值分解并对分解后的正交阵的最后5行进行初等行变换,以确定需要补偿的几何参数... 详细信息

为了标定一般7R冗余度串联机器人的所有几何参数,提出了一种实效的算法.首先,使用D-H矩阵对机器人建立了运动学模型和几何参数识别模型,对雅可比矩阵进行奇异值分解并对分解后的正交阵的最后5行进行初等行变换,以确定需要补偿的几何参数.通过机器人关节角和末端手爪位置的测量数据,计算雅可比矩阵以及手爪位置理论值和实测值的误差,采用最小二乘法对机器人的尺寸参数进行补偿量的计算.仿真过程表明,在有测量扰动的情况下,算法是稳定的和可靠的.最后,对机器人进行了实际的测量和标定,取得了满意的结果.

关键词：标定仿真最小二乘法奇异值分解运动学模型

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基于代数法的平面四杆机构五精确点轨迹综合

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北京邮电大学学报 2008年第2期31卷 1-4,25页

作者：黄昔光廖启征魏世民徐强北京邮电大学自动化学院北京100876

使用分次字典序Groebner基与Sylvester结式相结合的代数方法,研究了给定固定铰链位置的平面四杆机构五精确点轨迹综合问题.首先建立单个轨迹点的封闭方程;然后计算5个轨迹点方程组分次字典序Groebner基,从89个基中选取23个基构造Sylves... 详细信息

使用分次字典序Groebner基与Sylvester结式相结合的代数方法,研究了给定固定铰链位置的平面四杆机构五精确点轨迹综合问题.首先建立单个轨迹点的封闭方程;然后计算5个轨迹点方程组分次字典序Groebner基,从89个基中选取23个基构造Sylvester结式,不需要提取任何公因式,可直接获得一元36次方程及其全部封闭形式的解析解.为了对结果进行验证,使用同伦连续法对同一个数字算例进行计算,2种方法所得结果一致,说明该机构轨迹综合在复数域内最多有36组解.

关键词：轨迹综合机构综合 Groebner基 Sylvester结式

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前轮驱动自行车机器人定车运动的建模与实现

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北京邮电大学学报 2012年第2期35卷 5-9页

作者：黄用华廖启征魏世民郭磊北京邮电大学自动化学院北京100876

针对前轮驱动自行车机器人原地难以实现定车问题,提出一种简化的力学模型,并研究其部分反馈线性化控制策略.首先,考虑车轮纯滚动条件及定车时车把和车架垂直的特点,推导出前轮驱动角速度和车架航向角速率间的约束关系,并利用拉格朗日方... 详细信息

针对前轮驱动自行车机器人原地难以实现定车问题,提出一种简化的力学模型,并研究其部分反馈线性化控制策略.首先,考虑车轮纯滚动条件及定车时车把和车架垂直的特点,推导出前轮驱动角速度和车架航向角速率间的约束关系,并利用拉格朗日方程建立系统的动力学模型.然后,将系统欠驱动的车架横滚角线性化,并选择全部自由度为输出,根据部分反馈线性化原理设计定车运动控制器.仿真控制结果表明,适当地选取控制参数,系统可以在输入驱动力矩不大的情况下快速实现±10°范围内定车.物理样机实验进一步证明,利用所设计的控制器,前轮驱动自行车机器人可仅依靠前轮驱动实现小角度范围的原地定车运动.

关键词：自行车机器人前轮驱动定车运动动力学建模稳定平衡控制

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自平衡自行车机器人的运动学分析

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北京邮电大学学报 2011年第6期34卷 99-102页

作者：郭磊黄用华廖启征魏世民北京邮电大学自动化学院北京100876

针对一种自行车机器人进行了运动学分析,得到了机器人横滚角度与车把转角和驱动速度之间的函数关系.从理论上给出了能调整机器人平衡所需要的驱动速度下界,只要驱动速度高于此临界值,就能通过调整车把保持车体平衡.仿真结果表明,当机器... 详细信息

针对一种自行车机器人进行了运动学分析,得到了机器人横滚角度与车把转角和驱动速度之间的函数关系.从理论上给出了能调整机器人平衡所需要的驱动速度下界,只要驱动速度高于此临界值,就能通过调整车把保持车体平衡.仿真结果表明,当机器人具有不同横滚角度和车把转角的姿态时,要将其调整回平衡态所需的驱动速度处于以该临界值为下限的一个区间.基于这种运动学关系,进行了运动控制实验.通过将横滚角度理论计算值与实验数据进行对比,发现这两者基本一致,从而通过实验验证了所提出运动学分析的正确性.

关键词：自行车机器人运动学横滚角度车把转角驱动速度

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一种9杆巴氏桁架的位置分析

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北京邮电大学学报 2006年第3期29卷 12-16页

作者：王品廖启征魏世民庄育锋北京邮电大学自动化学院北京100876

使用复数向量法对9杆巴氏桁架4个回路建立几何关系,列出矢量方程组并转化成为复指数形式.首先使用结式对4个多项式方程直接消元,得到1个一元52次的多项式方程,再用辗转相除法求其他3个变量,在此过程中发现了6个增根.分析了产生增根的原... 详细信息

使用复数向量法对9杆巴氏桁架4个回路建立几何关系,列出矢量方程组并转化成为复指数形式.首先使用结式对4个多项式方程直接消元,得到1个一元52次的多项式方程,再用辗转相除法求其他3个变量,在此过程中发现了6个增根.分析了产生增根的原因并提出了消元过程中避免增根的改进措施,即寻找相关向量之间的关系,在消元过程中降低变量的次数,直接得到一元46次方程.最后通过一个算例,验证了这种巴氏桁架的解析解的数目为46.

关键词： 9杆巴氏桁架位置分析结式消元法辗转相除法

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Effect of pre-twinning and heat treatment on formability of AZX311 Mg alloy

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Journal of Magnesium and Alloys 2024年第3期12卷 1154-1169页

作者： Mahesh Panchal Lalit Kaushik min-Seong Kim Ravi Kottan Renganayagalu shi-Hoon Choi Jaiveer Singh Department of Mechanical Engineering Indian Institute of Technology JodhpurKarwarJodhpur 342030RajasthanIndia Department of Metallurgical and Materials Engineering Indian Institute of Technology JodhpurKarwarJodhpur 342030RajasthanIndia Energy Materials Research Center Korea Institute of Science and Technology(KIST)5 Hwarang-roSeongbuk-guSeoul 02792Republic of Korea Department of Advanced Components and Materials Engineering Sunchon National University255 Jungang-roSuncheonJeonnam 57922Republic of Korea

In this study,the effects of pre-strain-induced tensile twins(TTWs)and controlled heat treatment on the formability behavior of AZX311 Mg alloy sheets were investigated.A 4%compressive strain was applied to pre-strain the sheets using the in-plane compression(IPC)technique along the rolling direction(RD)to introduce *** pre-strained(PS)samples were subsequently heat-treated at 250℃,350℃,and 400℃ independently for 1 hr,and are termed as PSA1,PSA2,and PSA3,*** cupping tests were conducted to assess the formability of the sheet samples under different initial *** results showed that the PS sample heat-treated at 250℃ for 1hr exhibited a decrease in the Erichsen index(IE)compared to the as-rolled sample,whereas PSA2 and PSA3 samples showed an increase in IE *** analysis revealed that most of the TTWs generated through pre-twinning were stable at 250℃;however,the twin volume fraction reduced to 41%at 350℃ compared to the PS samples due to enhanced thermal activity at that ***,PSA2 samples showed severe grain coarsening in some areas of the sample,and the fraction of such grains increased in the PSA3 *** stretch formability(IE value)of PSA2 samples showed a 32.3%increase compared to the as-rolled ***,the analysis of the deformed specimen at failure under the Erichsen test indicated that considerable detwinning occurs in the PS and PSA1 samples,whereas dislocation slip activity dominates in the PSA2 and PSA3 samples during stretch *** from detwinning and dislocation slip,deformation twins were also observed in all samples after the Erichsen ***,this work highlights the importance of texture control and its underlying mechanisms via pre-twinning followed by heat treatment and their impact on the room temperature(RT)stretch formability of AZX311 Mg alloy sheets.

关键词： Mg alloys Pre-twinning Texture Formability EBSD.

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Two-dimensional C_(2)N-based single-atom catalyst with complex microenvironment for enhanced electrochemical nitrogen reduction:A descriptor-based design

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Journal of Energy Chemistry 2024年第10期97卷 110-119,I0003页

作者： Enduo Dai wei An Ruixian Guo Xugen shi Yunyi Li Yibo Wang mingming Liu College of Chemistry and Chemical Engineering.Shanghai University of Engineering Science Shanghai 201620China

The catalytic descriptor with operational feasibility is highly desired towards rational design of high-performance catalyst especially the electrode/electrolyte solution interface working under mild ***,we demonstrate that the descriptorΩparameterized by readily accessible intrinsic properties of metal center and coordination is highly operational and efficient in rational design of single-atom catalyst(SAC)for driving electrochemical nitrogen reduction(NRR).Using twodimensional metal(M)-B_(x)P_(y)S_(z)N_m@C_(2)N as prototype SAC models,we reveal that^(*)N_(2)+(H~++e~-)→^(*)N_(2)H acts predominantly as the potential-limiting step(PLS)of NRR on M-B_(2)P_(2)S_(2)@C_(2)N and M-B_(1)P_(1)S_(1)N_(3)@C_(2)N regardless of the distinction in coordination *** the 28 screened M active sites,withΩvalues close to the optimal 4,M-B_(2)P_(2)S_(2)@C_(2)N(M=V(Ω=3.53),Mo(Ω=5.12),and W(Ω=3.92))and M-B_(1)P_(1)S_(1)N_(3)@C_(2)N(M=V(Ω=3.00),Mo(Ω=4.34),and W(Ω=3.32))yield the lowered limiting potential(U_(L))as-0.45,-0.54.-0.36,-0.58,-0.25,and-0.24 V,respectively,thus making them the promising NRR *** importantly,these SACs are located around the top of volcano-shape plot of U_(L) versusΩ,re-validatingΩas an effective descriptor for accurately predicting the high-activity NRR SACs even with complex *** study unravels the relationship between active-site structure and NRR performance via the descriptorΩ,which can be applied to other important sustainable electrocatalytic reactions involving activation of small molecules viaσ-donation andπ^(*)-backdonation mechanism.

关键词： Electrocatalysis N_(2) reduction Single-atom catalyst Descriptor DFT

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Lightweight and high-security laser-based cotton tip pruning robot

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International Journal of Agricultural and Biological Engineering 2024年第4期17卷 98-108页

作者： Xuan'ang Guo Ziyang Mao Zedong shi wei Lu School of Artificial Intelligence Nanjing Agricultural UniversityNanjing 210031China

Considering the current environmental pollution caused by chemical topping,plant damage caused by mechanical topping,and the high cost of manual topping,a laser-based cotton-tip pruning robot for field cotton was designed in this *** main advantages of this robot include its safety,light weight,low cost,and environmental ***,the structural design,measurement,and corresponding control system design of the robot were ***,a precise laser control method based on Yolov5 cotton top identification and the inverse kinematic solution of parallel robot rapid positioning were ***,the optimal laser irradiation wavelength and duration were ***,a laser-topping experiment was conducted,and the overall accuracy and recall rates for cotton identification were 98.3%and 99.3%,*** AP and mAP at the threshold value of 0.5 reached 99.3%and 78.8%,*** maximum positioning error of the jacking system is 2.6 mm,and the repeated positioning error is within±1.2 cm,which meets the accuracy requirements of laser ***-purple laser irradiation at 15 W and 405 nm for 22 s was the best topping *** the effects of cotton topping with and without manual topping,it can be seen that laser topping significantly improved the yield and *** with the photothermal response of the cotton topping,the feasibility of laser topping was verified both theoretically and *** laser-topping scheme proposed in this study exhibits high efficiency,environmental protection,and safety,as well as good application prospects.

关键词： laser topping parallel manipulator photothermal response object detection

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Different concentrations of hyaluronic acid eye drops for dry eye syndrome: a systematic review and Meta-analysis

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International Journal of Ophthalmology(English edition) 2024年第6期17卷 1110-1119页

作者： Xiao-wei Ouyang Sheng Fang Yun-min Yi shi-Peng Zou Qi-Yu Hu Zi-Xuan Huang Qing-Xia Li Jin-Yan Luo Department of Ophthalmology Nanchang Hongdu Hospital of Traditional Chinese MedicineNanchang 330000Jiangxi ProvinceChina Department of Ophthalmology Jiangxi Hospital of Integrated Traditional Chinese and Western MedicineNanchang 330000Jiangxi ProvinceChina Department of Cataract Nanchang University Affiliated Eye HospitalNanchang 330000Jiangxi ProvinceChina Department of Neuro-ophthalmology Nanchang University Affiliated Eye HospitalNanchang 330000Jiangxi ProvinceChina

AIM:To compare high or low concentration of hyaluronic acid eye drops(HY)for dry eye syndromes(DES).METHODS:Randomized controlled trials(RCTs)comparing various concentrations of HY were searched in PubMed,Embase,Web of Science,Cochrane,SinoMed,CNKI,Wanfang Database,CQVIP,and Chinese journals databases between inception and July *** standardized mean differences(SMD)or weighted mean difference(WMD)with 95%confidence intervals(CI)from RCTs evaluating Schirmer’s I test(SIT),corneal fluorescein staining score(CFS),tear breakup time(TBUT),DES score(DESS),and Ocular Surface Disease Index(OSDI)were *** analysis,Egger’s test and Meta-regression analysis were performed for all ***:We conducted a Meta-analysis of 10 RCTs that met the inclusion criteria,involving 1796 ***-concentrations group significantly improved the outcome of CFS according to random effects modelling(SMD,-3.37;95%CI,-5.25 to-1.48;P=0.0005).The rest of the results were not statistically significant,including indicators such as SIT,TBUT,DESS and ***:For dry eyes with positive corneal staining,a high concentration of HY is recommended,whereas in other cases,a high concentration of HY does not offer a more pronounced advantage over a low concentration of HY in the treatment of dry eyes.

关键词： dry eye hyaluronic acid concentration Meta-analysis

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