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Improve access to the EU market by identifying French consumer preference for fresh fruit from China

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Journal of Integrative Agriculture 2018年第6期17卷 1463-1474页

作者： WANG Er-peng zhifeng gao Yan Heng School of Economics and Management Nanjing Tech University College of Economics and Management Jilin Agricultural University Food and Resource Economics Department University of Florida

Most previous studies have investigated country-of-origin effect for agricultural products from the economically developed country, but few have focused on the impact of country-of-origin on agricultural products from economically developing countries. Using a national online survey in France, we determine French consumers＇ perceptions and preferences for fresh fruit from China. Results of ordered logit models show that fresh fruit from China was perceived as low quality and unsafe. Respondents who care about country-of-origin were less likely to purchase fresh fruit from China, while those who care about brand were more likely to buy Chinese fresh fruit. Risk perception and quality perception both had a significant impact on the purchase of Chinese fresh fruit. Results of latent class models obtained with key consumer demographics show that heterogeneous preferences exist among different consumer groups. The results provide critical information to both China and other economically developing countries in their efforts to improve market penetration in economically developed countries.

关键词： country of origin perception consumer preference fresh fruit China

Adaptive sliding mode backstepping control for near space vehicles considering engine faults

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Journal of Systems Engineering and Electronics 2018年第2期29卷 343-351页

作者： ZHAO Jing JIANG Bin XIE Fei gao zhifeng XU Yufei College of Automation Engineering Nanjing University of Posts and TelecommunicationsNanjing 210023China College of Automation Engineering Nanjing University of Aeronautics and AstronauticsNanjing 210016China School of Electrical and Automation Engineering Nanjing Normal UniversityNanjing 210046China Jiangsu Province 3D Printing Equipment and Manufacturing Key Lab Nanjing 210042China Shanghai Institute of Satellite Engineering Shanghai 200240China Jiangsu Engineering Laboratory for Internet of Things and Intelligent Robots Nanjing 210023China

A fault tolerant control methodology based adaptive sliding mode(ASM) backstepping is proposed for near space vehicle(NSV) attitude control system under engine faults. The proposed scheme combined adaptive backstepping with the sliding mode control strategy could guarantee the system’s stability and track desired signals under external disturbances and engine faults. Firstly, attitude mode description and the engine faulty model are given. Secondly, a nominal control law is ***, a sliding mode observer is given later in order to estimate both the information of engine faults and external disturbances. An adaptive sliding mode technology based on the previous nominal control law is developed via updating faulty parameters. Finally,analyze the system’s fault-tolerant performance and reliability through experiment simulation, which verifies the proposed design of fault-tolerant control can tolerate engine faults, as well as the strong robustness for external disturbance.

关键词： fault tolerant control adaptive sliding mode(ASM) engine fault near space vehicle(NSV)

Changing structure of China's meat imports

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Journal of Integrative Agriculture 2015年第6期14卷 1081-1091页

作者： CHENG Ya-hao zhifeng gao James Seale Jr. Department of Economics Nankai University Food and Resource Economics Department University of Florida

This paper discusses the determinants of meat imports of China. Results indicate that import demand is mostly determined by import price and real GDP. Imported price has a negative effect and real GDP has a positive influence on import quantity. Tariff does not have a significant effect. As GDP and consumption capacity increases, China has a large potential demand for meat imports. Some countries may gain if China＇s economy continues expanding, while others, like the United States, are the most sensitive to the trade policy of China.

关键词： imports Zealand expanding Australia income prices capita Fresh mostly accounting

Consumers'willingness to pay for ethical consumption initiatives on e-commerce platforms

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Journal of Integrative Agriculture 2021年第4期20卷 1012-1020页

作者： WANG Er-peng AN Ning GENG Xian-hui zhifeng gao Emmanuel KIPROP School of Economics and Management Nanjing Tech UniversityNanjing 211816P.R.China College of Economics and Management Nanjing Agricultural UniversityNanjing 210095P.R.China Food and Resource Economics Department University of FloridaGainesvilleFL 32611-0240USA

Despite China's fast-growing e-commerce and its great achievement in promoting poverty alleviation through consumption,little is known about Chinese consumers'online ethical *** the payment card elicitation method,this paper designs a within-subject survey and a between-subject survey to investigate Chinese consumers'quality perception and preference for apples from poverty-stricken *** results show that before"information shock",emphasizing that taste and safety attributes of apples from poverty-stricken areas are the same as the conventional ones,Chinese consumers on average are willing to pay a 31%premium for apples from poverty-stricken ***"information shock",both the within-subject and between-subject designs show a minimal drop of the premium,implying that the ethical attribute is the main motivation for buying apples from poverty-stricken *** regression results show that quality perception of private attributes has significant effect on consumers'willingness to pay(WTP)for apples from poverty-stricken areas,and trust in government supervision of e-commerce plays an essential role in motivating online ethical consumption.

关键词： ethical consumption apples from poverty-stricken areas WTP interval regression

Characteristics and ozone formation potential of volatile organic compounds in emissions from a typical Chinese coking plant

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Journal of Environmental Sciences 2020年第9期32卷 183-189页

作者： Xinmin Zhang Di Wang Yan Liu Yufan Cui Zhigang Xue zhifeng gao Jinhong Du State Key Laboratory of Environmental Criteria and Risk Assessment Chinese Research Academy of Environmental SciencesBeijing 100012China

Coking industry is an important volatile organic compounds(VOCs) emission source in China,however,detailed information on VOCs emissions is ***,we selected a typical mechanized coking plant and collected air samples according to the Emission Standard of Pollutants for Coking Chemical Industry(GB16171-2012).Using gas chromatographymass spectrometry method,we analyzed the VOCs in the air samples,and applied maximum increment reactivity(MIR) rule to estimate ozone formation potential(OFP) of the VOCs emitted from the coke *** than 90 VOCs species were detected from the coking plant,including alkanes,alkenes,alkynes,aromatic hydrocarbons,halogenated hydrocarbons and oxygenated *** concentrations of VOCs(p(VOCs)) generated at different stages of the coking process are significantly different.p(VOCs) from coke oven chimney had the highest concentration(87.1 mg/m3),followed by coke pushing(4.0 mg/m3),coal charging(3.3 mg/m3) and coke oven tops(1.1 mg/m3).VOCs species emitted from the coke production processes were dominated by alkanes and alkenes,but the composition proportions were different at the different *** were the most abundant emission species in flue gases of the coke oven chimney accounting for up to 66% of the total VOCs,while the VOCs emissions from coke pushing and coal charging were dominated by alkanes(36% and 42%,respectively),and the alkanes and alkenes emitted from coke oven top were similar(31% and 29%,respectively).Based on above results,reduction of VOCs emissions from coke oven chimney flue gases is suggested to be an effective measure,especially for alkenes.

关键词： ozone volatile gases

A sliding mode control algorithm based on improved super-twisting and its application to quadrotors

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Journal of Control and Decision 2023年第3期10卷 433-442页

作者： Jing Zhao Zuoyu Xie Min Xiao Fengyu Xu zhifeng gao College of Automation and College of Artificial Intelligence Nanjing University of Posts and TelecommunicationsNanjingPeople’s Republic of China

This paper presents a fast terminal sliding mode control strategy based on improved supertwistingalgorithm (IST-FTSMC) for quadrotors with external disturbances. First, the dynamicmodel of quadrotors is described. Then, a control strategy based on fast terminal sliding modewith improved super-twisting algorithm is proposed for attitude subsystem and position ***, some comparative results show superior tracking performance of the proposedmethod in this paper under external disturbances.

关键词： Quadrotor super-twisting sliding mode control trajectory tracking external disturbances

Experimental study on filtering,transporting, concentrating and focusing of microparticles based on optically induced dielectrophoresis

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Science China(Technological Sciences) 2010年第9期53卷 2388-2396页

作者： ZHU XiaoLu,YIN zhifeng,gao ZhiQiang & NI ZhongHua Jiangsu Key Laboratory for Design and Manufacture of Micro-Nano Biomedical Instruments,Southeast University,Nanjing 211189,China Jiangsu Key Laboratory for Design and Manufacture of Micro-Nano Biomedical Instruments Southeast University Nanjing China

The key problem to be solved for the dielectrophoresis (DEP) application is to provide dynamically reconfigurable microelectrodes and low-cost methodology for bioparticle *** emergence of optically induced DEP (ODEP) based on photoconductive effect provides a potential solution for the above *** this paper,an ODEP chip is designed and fabricated,and the corresponding experimental platform was established,whereupon four types of particle manipulation regimes–filtering,transporting,concentrating and focusing based on ODEP are experimentally demonstrated and the operating performances are quantitatively *** experiment results show that the functions and performances of ODEP manipulation are heavily dependent on the geometrical shape,scales and speed of optical patterns,actuating signal frequency and the electric conductivity of the *** manipulation efficiency can increase by more than 50% via increasing the optical line ***,the efficiency is obviously affected by the inclination angle of the optical oblique lines in the manipulation of particle ***,the maximum velocity of particles increases with the increment of the inside radius and the thickness of the optical trapping *** manipulation efficiency is always related to signal frequency and solution conductivity,and empirically,satisfactory performance and high efficiency are obtained when the solution electric conductivity ranges from 5×10-4 S/m to 5×10-3 S/m.

关键词： optically-induced dielectrophoresis particle manipulation filtering transporting concentrating focusing

Delay-Dependent Robust Passive Control for Uncertain Discrete-Time Systems with Time Delays

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Open Journal of Discrete Mathematics 2013年第3期3卷 123-126页

作者： Jufang Wang Changlong Yu zhifeng gao College of Sciences Hebei University of Science and Technology Shijiazhuang China Nanjing University of Aeronautics and Astronautics Nanjing China

This paper considers the problem of robust passive control for uncertain discrete systems with time-varying delays. We pay attention to designing a state feedback controller which guarantees the passivity of the closed-loop system for all admissible uncertainties. In terms of a linear matrix inequality, a sufficient condition for the solvability of this problem is presented and the explicit expression of the desired state feedback controller is given.

关键词： Robust Passive Control Discrete Systems Time Delay

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最小方差谱估计中匹配滤波器迭代求解算法

仪器仪表学报 2013年第7期34卷 1479-1484页

作者：彭宇高志峰彭喜元哈尔滨工业大学自动化测试与控制研究所哈尔滨150001 山东大学(威海)机电与信息工程学院威海264209

基于匹配滤波器组的最小方差谱估计方法,由一组匹配滤波器输出计算输入信号的谱估计值,其匹配滤波器的求解基于自相关矩阵逆矩阵,受到矩阵维数和奇异性的限制。提出一种迭代求解算法直接计算匹配滤波器,基于简化的复系数凸二次优化问题... 详细信息

基于匹配滤波器组的最小方差谱估计方法,由一组匹配滤波器输出计算输入信号的谱估计值,其匹配滤波器的求解基于自相关矩阵逆矩阵,受到矩阵维数和奇异性的限制。提出一种迭代求解算法直接计算匹配滤波器,基于简化的复系数凸二次优化问题来实现,回避了矩阵求逆。算法具有二次终止性质,在有限次迭代内达到最优解。而限制迭代次数可以对频率分辨率和谱线不匹配现象折中,以得到更高谱峰幅度。实验采用新算法实现MVDR和CCA算法匹配滤波器,并对谱估计结果进行比较。

关键词：匹配滤波器矩阵求逆凸二次规划 MVDR CCA 频率估计