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基于信息技术的自动修剪机参数监控与分析

农机化研究 2022年第1期44卷 208-212页

作者：杨正张鹏河北能源职业技术学院河北唐山063000

以自动修剪机运行参数监控系统为研究对象,基于信息采集技术,搭建一种通过位置传感器、角度传感器实现的运行过程参数监控系统。修剪机自动工作过程中,参数监控系统进行修剪机运行参数采集,并与控制系统中的设定值进行比对,进行插补控... 详细信息

以自动修剪机运行参数监控系统为研究对象,基于信息采集技术,搭建一种通过位置传感器、角度传感器实现的运行过程参数监控系统。修剪机自动工作过程中,参数监控系统进行修剪机运行参数采集,并与控制系统中的设定值进行比对,进行插补控制指令修正,实现修剪机运行过程的闭环控制。系统运行参数采集分析表明:自动修剪机运行过程中的转动角度、位移、速度及加速度等参数与系统设定值基本相符,但随着修剪过程的推移,实际运行参数与系统初始设定值之间偏差会逐渐增大。

关键词：自动修剪机信息采集技术过程参数

ANP-GRAP方法在军校教学能力竞赛中的应用

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计算机工程与应用 2015年第12期51卷 260-263,270页

作者：张强张鹏李长波解放军理工大学军教院南京211101 解放军理工大学训练部南京210007

针对军校教学能力竞赛规则中存在的主要问题,采用网络层次分析法与灰色关联分析法集成的方案,提出具体改进措施。着眼教学能力评价指标间具有较强相互影响的实际,利用网络层次分析法确定各指标权重;构建灰色关联分析模型,提出求解评价... 详细信息

针对军校教学能力竞赛规则中存在的主要问题,采用网络层次分析法与灰色关联分析法集成的方案,提出具体改进措施。着眼教学能力评价指标间具有较强相互影响的实际,利用网络层次分析法确定各指标权重;构建灰色关联分析模型,提出求解评价结果的思路;采集某次教学能力竞赛的原始数据,通过实例验证该评价模型的有效性。

关键词：军事教育教学能力竞赛规则网络层次分析灰色关联分析

YC_(x)F_(y)nanosheets-supported Ni nanoparticles as a high-efficient catalyst for hydrogen desorption of MgH_(2)

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Nano Research 2023年第8期16卷 10938-10945页

作者： Cong peng Qingan zhang School of Materials Science and Engineering Anhui University of TechnologyMaanshan 243002China

Magnesium hydride(MgH_(2))has been considered as a promising hydrogen storage material,but the pressing issues including sluggish kinetics and poor cyclic stability hampered its practical applications.Herein,a high-efficient catalyst comprising of YC_(x)F_(y)nanosheets-supported Ni nanoparticles(Ni_(30)/YC_(x)F_(y))was designed and constructed aiming to resolve the abovementioned restrictions facing MgH_(2).After hybridizing with Ni_(30)/YC_(x)F_(y),the as-achieved MgH_(2)–10 wt.%Ni_(30)/YC_(x)F_(y)composite exhibits superior hydrogen desorption kinetics with an activation energy of 80.9 kJ·mol^(−1)and a high capacity retention of 97.6%after 50 cycles.It is confirmed that the in situ formed Mg_(2)NiH_(4)and YH3 catalytic phases accelerate the hydrogen desorption kinetics,while the dispersed MgF_(2)and carbon species prevent the crystallite growth,particle aggregation,and catalyst redispersion,contributing an excellent cyclic stability.This work provides a new strategy to synthesize efficient catalysts for hydrogen desorption of MgH_(2).

关键词： hydrogen storage magnesium hydride catalyst kinetics cyclic stability

Electrochemical transformation of biomass-derived oxygenates

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Science China Chemistry 2023年第4期66卷 1011-1031页

作者： peng Zhou Jie zhang School of Chemistry Monash UniversityClaytonVictoria 3800Australia

Replacing conventional fossil resources with renewable raw materials for chemical production and energy generation is crucial for achieving the carbon-neutral goal and alleviating the emerging energy crisis.Biomass has been considered as one of the most promising candidates for this purpose owing to its great natural abundance and inherent ability to fix CO_(2) in the form of multicarbon compounds.Particularly,biomass conversion through an electrochemical route is intriguing because of its operability near ambient conditions,flexible scalability(suitable for distributed manufacturing and even domestic use)and green generation of oxidative or reductive equivalents instead of wasteful and possibly explosive or flammable reagents.Herein,recent progress in electrochemical transformation of biomass,including hydrogenation and amination,is reviewed with the emphasis on catalysts and strategies for enhancing catalytic efficiency.The advances in mechanistic understanding using in-situ spectroscopy are also briefly discussed.Finally,recommendations for the directions for future development are also provided.

关键词： biomass utilization electrochemical hydrogenation reductive amination catalyst in-situ spectroscopy mechanism

Multicriteria optimization problems of finite horizon stochastic cooperative linear-quadratic difference games

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Science China(Information Sciences) 2022年第7期65卷 197-209页

作者： Chenchen peng Weihai zhang College of Electrical Engineering and Automation Shandong University of Science and Technology

This paper investigates the Pareto optimality of the regular and the indefinite stochastic cooperative linear-quadratic difference games in a finite time horizon. We derive a general form and a linear property of the solution to the linear stochastic difference system by defining several sequences of bounded and linear operators. The performance criteria’s convexity can be guaranteed naturally under the weighted matrices’ constraints for the regular cooperative game, and the weighting technique can well characterize the Pareto optimality. We also establish a novel convexity criterion for the cost functionals of the indefinite cooperative game, in which we find that the minimization of the performance criteria’s weighted sum is equivalent to the Pareto optimal strategies. To derive all the Pareto optimal strategies and solutions, we present a computing algorithm using the weighted difference Riccati equation and the weighted difference Lyapunov equation for the regular and the indefinite cases. We present a practical example in the economy to validate the results.

关键词： multicriteria optimization problems Pareto optimality cooperative difference games discrete-time stochastic LQ theory the difference Riccati equation the difference Lyapunov equation

Effect of Ti and Ce Microalloy on Microstructure and Properties of Al-Si-Cu-Zr-Sr Cast Aluminum Alloy

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Journal of Wuhan University of Technology(Materials Science) 2023年第4期38卷 897-902页

作者：姚辉许晓静 zhang Rikai ZHANG Peng SUN Zhiwei WANG Hao Institute for Advanced Manufacturing and Modern Equipment Technology Jiangsu UniversityZhenjiang212013China

The effect of Ti and Ce microalloying on the mechanical properties of Al-9Si-3.5Cu-0.2Zr-0.1Sr cast aluminum alloy was investigated,and it was hoped that the cast aluminum alloy with excellent comprehensive properties could be obtained.On the basis of Zr-Sr microalloyed cast aluminum alloy(Al-9Si-3.5Cu-0.2Zr-0.1Sr),the effects of 0.2Zr-0.1Sr-0.16Ti ternary microalloying and 0.2Zr-0.1Sr-0.16Ti-0.1Ce quaternary microalloying on the microstructure and properties of the alloy were investigated.The experimental results show that compared with Zr-Sr microalloying,Zr-Sr-Ti microalloying and Zr-Sr-Ti-Ce microalloying can effectively refine the microstructure,improve the modification effect of Si phase,and promote the improvement of Al_(2)Cu phase,thus improving the properties.The higher the degree of microalloying,the hardness is gradually increasing,but the electrical conductivity is gradually decreasing.Zr-Sr-Ti microalloying can increase the tensile strength of the alloy to 400.07 MPa and the elongation to 9.5%.Zr-Sr-Ti-Ce microalloying do not continue to improve the properties of the alloy,and the tensile strength and elongation after fracture decrease to a certain extent due to the addition of Ce.Therefore,the best comprehensive properties can be obtained by ZrSr-Ti microalloying(Al-9Si-3.5Cu-0.2Zr-0.1Sr-0.16Ti).

关键词： cast aluminum alloy microalloying mechanical properties Al-Si-Cu

Secondary Frequency Control Considering Optimized Power Support From Virtual Power Plant Containing Aluminum Smelter Loads Through VSC-HVDC Link

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Journal of Modern Power Systems and Clean Energy 2023年第1期11卷 355-367页

作者： peng Bao Wen zhang Yuxi zhang Key Laboratory of Power System Intelligent Dispatch and Control of the Ministry of Education Shandong UniversityJinan 250061China

The growing number of renewable energy replacing conventional generators results in a loss of the reserve for frequency control in power systems,while many industrial power grids often have excess energy supply due to abundant wind and solar energy resources.This paper proposes a secondary frequency control(SFC)strategy that allows industrial power grids to provide emergency high-voltage direct current(HVDC)power support(EDCPS)for emergency to a system requiring power support through a voltage source converter(VSC)HVDC link.An architecture including multiple model predictive control(MPC)controllers with periodic communication is designed to simultaneously obtain optimized EDCPS capacity and minimize adverse effects on the providing power support(PPS)system.Moreover,a model of a virtual power plant(VPP)containing aluminum smelter loads(ASLs)and a high penetration of wind power is established for the PPS system.The flexibility and controllability of the VPP are improved by the demand response of the ASLs.The uncertainty associated with wind power is considered by chance constraints.The effectiveness of the proposed strategy is verified by simulation results using the data of an actual industrial power grid in Inner Mongolia,China.The DC voltage of the VSCs and the DC in the potlines of the ASLs are also investigated in the simulation.

关键词： Secondary frequency control power support voltage source converter(VSC) high-voltage direct current(HVDC) model predictive control(MPC) virtual power plant(VPP) demand response

Fatigue cracking criterion of high-strength steels induced by inclusions under high-cycle fatigue

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Journal of Materials Science & Technology 2023年第23期154卷 114-128页

作者： peng Wang peng zhang Bin Wang Yankun Zhu Zikuan Xu Zhefeng zhang Shi-changxu Innovation Center for Advanced Materials Institute of Metal Research Chinese Academy of Sciences Shenyang 110016 China School of Materials Science and Engineering University of Science and Technology of China Shenyang 110016 China

Fatigue properties of high-strength steels become more and more sensitive to inclusions with enhancing the ultimate tensile strength (UTS) because the inclusions often cause a relatively low fatigue strength and a large scatter of fatigue lives. In this work, four S–N curves and more than 200 fatigue fracture morphologies were comprehensively investigated with a special focus on the size and type of inclusions at the fatigue cracking origin in GCr15 steel with a wide strength range by different heat treatments after high-cycle fatigue (HCF). It is found that the percentage of fatigue failure induced by the inclusion including Al2 O3 and TiN gradually increases with increasing the UTS, while the percentage of failure at sample surfaces decreases conversely and the fatigue strength first increases and then decreases. Besides, it is interestingly noted that the inclusion sizes at the cracking origin for TiN are smaller than that for Al2 O3 because the stress concentration factor for TiN is larger than that for Al2 O3 based on the finite element simulation. For the first time, a new fatigue cracking criterion including the isometric inclusion size line in the strength-toughness coordinate system with specific physical meaning was established to reveal the relationship among the UTS, fracture toughness, and the critical inclusion size considering different types of inclusions based on the fracture mechanics. And the critical inclusion size of Al2 O3 is about 1.33 times of TiN. The fatigue cracking criterion could be used to judge whether fatigue fracture occurred at inclusions or not and provides a theoretical basis for controlling the scale of different inclusion types for high-strength steels. Our work may offer a new perspective on the critical inclusion size in terms of the inclusion types, which is of scientific interest and has great merit to industrial metallurgical control for anti-fatigue design.

关键词： High-strength steel High-cycle fatigue Critical inclusion size Inclusion types Tensile strength Fracture toughness Fatigue cracking criterion

CD4+T Cell Recovery among Patients with HIV/AIDS who Received Highly Active Antiretroviral Therapy Regularly in Chongqing,China:An Ambispective Cohort Study

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Biomedical and Environmental Sciences 2022年第3期35卷 254-258页

作者： ZHANG Peng YAN Xiang Yu LI Yong Jie zhang Bo WANG Jing Jiulongpo District Center for Disease Control and Prevention Chongqing 400030China School of Public Health Peking UniversityBeijing 100191China Department of Laboratory the Second People's Hospital of Jiulongpo DistrictChongqing 400030China

The HIV/AIDS epidemic in China is spreading rapidly,with the number of people living with HIV(PLHIV)increasing nearly 1.5 times from 0.44 million in 2011 to 1.05 million in 2020^([1,2]).Antiretroviral therapy(ART)is t... 详细信息

关键词： HIV/AIDS Therapy Chongqing