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The role of time preferences in contract breach:Evidence from Chinese poultry farmers participating in contract farming

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Journal of Integrative Agriculture 2023年第2期22卷 623-641页

作者： HOU Jing ZHOU Li Jennifer IFFT YING rui-yao Business School Jiangsu Normal UniversityXuzhou 221116P.R.China College of Economics and Management Nanjing Agricultural UniversityNanjing 210095P.R.China Department of Agricultural Economics Kansas State UniversityManhattanKansas 66506USA

Farmers’contract breach behavior is cited as one of the major stumbling blocks in the sustainable expansion of contract farming in many developing *** paper examines farmers’contract breach decisions from the perspective of time *** empirical analysis is based on a household survey and economic field experiments of poultry households participating in contract farming conducted in Jiangsu Province,China.A discounted utility model and a maximum likelihood technique are applied to estimate farmers’time preferences and the effect of time preferences on contract breach in the production and sales phases are explored with a bivariate probit *** results show that,on average,the poultry farmers in the sample are generally present biased and impatient regarding future *** regression results show that farmers with a higher preference for the present and a higher discount rate are more likely to breach contracts,and time preferences play a greater role in the production phase than in the sales *** considering heterogeneity,specific investments and transaction costs promote contract stability only for farmers with a low degree of ***,compared with large-scale farmers,small-scale farmers’contract breach decisions are more significantly affected by their time *** results have implications for contract stability policies and other issues that are impacted by the linking of behavioral preferences to agricultural decisions.

关键词： time preferences contract breach contract farming economic field experiments China

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Deep Active Learning for Solvability Prediction in Power Systems

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Journal of Modern Power Systems and Clean Energy 2022年第6期10卷 1773-1777页

作者： Yichen Zhang Jianzhe Liu Feng Qiu Tianqi Hong rui yao Argonne National Laboratory LemontIL 60439USA IEEE

Traditional methods for solvability region analysis can only have inner approximations with inconclusive conservatism and handle limited types of power flow *** this letter,we propose a deep active learning framework for solvability prediction in power *** with passive learning where the training is performed after all instances are labeled,active learning selects most informative instances to be labeled and therefore significantly reduces the size of the labeled dataset for *** the active learning framework,the acquisition functions,which correspond to different sampling strategies,are defined in terms of the on-the-fly posterior probability from the ***,the IEEE 39-bus system is employed to validate the proposed framework,where a two-dimensional case is illustrated to visualize the effectiveness of the sampling method followed by the high-dimensional numerical ***,the Northeast Power Coordinating Council(NPCC)140-bus system is used to validate the performance on large-scale power systems.

关键词： Active learning deep learning power flow solvability power flow equation

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Polyethylene glycol-supported ionic liquid as a highly efficient catalyst for the synthesis of propylene carbonate under mild conditions

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Frontiers of Chemical Science and Engineering 2012年第3期6卷 239-245页

作者： rui yao Hua WANG Jinyu HAN Key Laboratory for Green Chemical Technology of State Education Ministry School of Chemical Engineering&TechnologyTianjin UniversityTianjin 300072China

The coupling reaction ofpropylene and CO2 to form propylene carbonate （PC） was promoted by an ionic liquid （IL） covalently bound to polyethylene glycol （PEG）. The supported ionic liquid, which has both acidic and basic components, proved to be an active catalyst for PC synthesis under mild conditions. The effects of different cations and anions, reaction temperature, CO2 pressure, and reaction time were investigated. It was demonstrated that the acid group in the catalyst plays an important role in the reaction. With this system, a high PC yield （95%） was achieved under mild conditions （3.0 MPa, 120℃ and 4 h） without a co-solvent. In addition, the catalyst was readily recovered and reused. Based on the experimental results, a plausible mechanism for the catalyst was proposed.

关键词： ionic liquid PEG-supported ionic liquid,carbon dioxide propylene carbonate

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Amorphous iron-nickel phosphide nanocone arrays as efficient bifunctional electrodes for overall water splitting

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Green Energy & Environment 2021年第4期6卷 496-505页

作者： Guang Liu Yun Wu rui yao Fei Zhao Qiang Zhao Jinping Li Shanxi Key Laboratory of Gas Energy Efficient and Clean Utilization College of Chemistry and Chemical EngineeringTaiyuan University of TechnologyTaiyuanShanxi 030024China Key Laboratory of Advanced Energy Materials Chemistry(Ministry of Education) College of ChemistryNankai UniversityTianjin 300071China

The synthesis of low-cost and highly active electrodes for both oxygen evolution reaction(OER)and hydrogen evolution reaction(HER)is very important for water *** this work,the novel amorphous iron-nickel phosphide(FeP-Ni)nanocone arrays as efficient bifunctional electrodes for overall water splitting have been in-situ assembled on conductive three-dimensional(3D)Ni foam via a facile and mild liquid deposition *** is found that the FeP-Ni electrode demonstrates highly efficient electrocatalytic performance toward overall water *** 1 M KOH electrolyte,the optimal FeP-Ni electrode drives a current density of 10 mA cm^(-2) at overpotential of 218 mV for the OER and120 mV for the HER,and can attain such current density for 25 h without performance ***,a two-electrode electrolyzer comprising the FeP-Ni electrodes can afford 10 mA cm^(-2) electrolysis current at a low cell voltage of 1.62 V and maintain long-term stability,as well as superior to that of the coupled RuO_(2)/NFk Pt/C/NF *** characterizations confirm that the excellent electrocatalytic performances for water splitting are attributed to the unique 3D morphology of nanocone arrays,which could expose more surface active sites,facilitate electrolyte diffusion,and benefit charge transfer and also favorable bubble detachment *** work presents a facile and cost-effective pathway to design and develop active self-supported electrodes with novel 3D morphology for water electrolysis.

关键词： Water splitting Oxygen evolution reaction Hydrogen evolution reaction Phosphides Bifunctional electrodes

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Mixed H_2/H_∞ filtering for a class of high-speed sampling uncertain systems

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Science in China(Series F) 2008年第5期51卷 560-570页

作者： ZHANG rui yao Yu MA KeMao CHEN SongLin Control and Simulation Center Harbin Institute of Technology Harbin 150001 China

The problem of mixed H2/H∞ filtering for polytopic Delta operator systems is investigated. The aim is to design a linear asymptotically stable filter which guarantees that the filtering error system has different performances in different filtering channels. Based on a parameter-dependent Lyapunov function, a new mixed H2/H∞ performance criterion is presented. Upon this performance criterion, a sufficient condition for the full-order mixed H2/H∞ filter is derived in terms of linear matrix inequalities. The filter can be obtained from the solution of a convex optimization problem. The proposed filter design procedure is less conservative than the strategy based on the quadratic stability notion. A numerical example is given to illustrate the feasibility of the proposed approach.

关键词： H2/H∞ filtering linear matrix inequality polytopic uncertainty

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Hybrid position/force control strategy and experiment of the six-cable driven parallel manipulator for the forty-meter aperture radio telescope

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High Technology Letters 2012年第3期18卷 230-237页

作者： Li Jian Tang Xiaoqiang Shao Zhufeng yao rui Department of Precision Instruments and Mechanology Tsinghua University Beijing 100084 P. R. China

This paper mainly analyzes a hybrid position/force control strategy and experiment of a six-cable driven parallel manipulator for a forty-meter aperture radio telescope. Through the establishments of a kinematic model, a catenary model and a cable-force characteristics model, a basic method is presented based on preventing the pseudo-drag problem of a flexible cable and realizing the hybrid position/force control for a six-cable driven parallel manipulator, and a hybrid position/force control system is developed. Some specific experiments in two typical velocities for astronomical observations are carried out. Experimental results show that the tracking accuracy is related to the speed of the movement. The desired tracking accuracy of the support system is achieved through an effective hybrid position/force control strategy, the cable forces are controlled effectively, and the pseudo-drag problem of flexible cable is solved. This study establishes the foundation of achieving the harmonious movement of the six-cable driven parallel manipulator, A-B rotating platform and the Stewart fine tuninz olatform.

关键词： large radio telescope six-cable driven parallel manipulator hybrid position/forcecontrol tracking accuracy

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Combining gradual and abrupt analysis to detect variation of vegetation greenness on the loess areas of China

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Frontiers of Earth Science 2022年第2期16卷 368-380页

作者： Panxing HE Zongjiu SUN Dongxiang XU Huixia LIU rui yao Jun MA Ministry of Education Key Laboratory for Western Arid Region Grassland Resources and Ecology College of Grassland and Environment SciencesXinjiang Agricultural UniversityUrumqi 830000China Ministry of Education Key Laboratory for Biodiversity Science and Ecological Engineering Institute of Biodiversity ScienceFudan UniversityShanghai 200438China School of Earth and Environmental Sciences University of QueenslandQueensland 4072Australia Hubei Key Laboratory of Critical Zone Evolution School of Geography and Information EngineeringChina University of GeosciencesWuhan 430074China

The annual peak growth and trend shift of vegetation are critical in characterizing the carbon sequestration capacity of *** the well-known area with the fastest vegetation growth in the world,the Loess Plateau(LP)lands find an enhanced greening trend in the annual and ***,the spatiotemporal dynamics of vegetation peak growth and breakpoints characteristics on time series still needs to be ***,we performed tendency analysis to characterize recent variations in annual peak vegetation growth through a satellite-derived vegetation index(NDVI_(max),Maximum Normalized Difference Vegetation Index)and then applied breakpoint analysis to capture abrupt points on the time *** results demonstrated that the vegetation peak trend had been significantly increasing,with a growth rate at 0.68×10^(-2)·a^(-1) during 2001-2018,and most pixels(70.81%)have a positive linear greening trend over the entire *** addition,about 83%of the breakpoint type on the monthly NDVI time series is a monotonic increase at the pixel level,and most pixels(57%)have detected breakpoints after *** results also showed that the growth rate accelerates in the northwest and decelerates in the southeast after the *** study indicates that combining abrupt analysis with gradual analysis can describe vegetation dynamics more effectively and *** findings highlighted the importance of breakpoint analysis for monitor timing and shift using time series satellite data at a regional scale,which may help stakeholders to make reasonable and effective ecosystem management policies.

关键词： vegetation greenness gradual trend breakpoint BFAST algorithm the Loess Plateau area

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Lattice strain induced by trace Pt single atoms in nickel for accelerating industrial hydrogen evolution

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Journal of Energy Chemistry 2024年第11期98卷 503-511页

作者： rui yao Yun Wu Kaiyang Zhang Shuhui Fan Qiang Zhao Jinping Li Guang Liu College of Chemical Engineering and Technology Shanxi Key Laboratory of Gas Energy Efficient and Clean UtilizationTaiyuan University of TechnologyTaiyuan 030024ShanxiChina Shanxi Research Institute of Huairou Laboratory Taiyuan 030031ShanxiChina

Strategically designing the electrocatalytic system and cleverly inducing strain is an effective approach to balance the cost and activity of Pt-based electrocatalysts for industrial-scale hydrogen ***,we present a unipolar pulsed electrodeposition(UPED) strategy to induce strain in the Ni lattice by introducing trace amounts of Pt single atoms(SAs)(0.22 wt%).The overpotential decreased by 183 mV at 10 mA cm^(-2) in 1.0 M KOH after introducing trace amounts of Pt_(SAs).The industrial electrolyzer,assembled with Pt_(SAs)Ni cathode and a commercial NiFeO_(x) anode,requires a cell voltage of 1.90 V to attain 1 A cm^(-2) of current density and remains stable for 280 h,demonstrating significant potential for practical *** aberration corrected scanning transmission electron microscopy(AC-STEM),X-ray absorption(XAS),and geometric phase analysis(GPA) indicate that the introduction of trace amounts of Pt SAs induces tensile strain in the Ni lattice,thereby altering the local electronic structure and coordination environment around cubic Ni for enhancing the water decomposition kinetics and fundamentally changing the reaction *** doping-strain strategy showcases conformational relationships that could offer new ideas to construct efficient hydrogen evolution reaction(HER) electrocatalysts for industrial hydrogen production in the future.

关键词： Unipolar pulsed electrodeposition Pt single atoms Ni lattice Hydrogen evolution reaction H intermediates

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Deviation Prevention Ability of Rollers in Continuous Annealing Furnace and Application

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Journal of Iron and Steel Research International 2012年第12期19卷 8-13页

作者： ZHANG Yan YANG Quan HE An-rui yao Xi-jiang GUO De-fu National Engineering Research Center of Advanced Rolling University of Science andTechnology Beijing Beijing 100083 China

In order to reduce the strip deviation in the practical production procedure in the continuous annealing fur- nace, a dynamic simulation model was built through finite element method （FEM） to conduct the quantification cal- culation of the effect of regular roller contour types on strip deviation. The result reveals that comparing to the flat roller, forward roller contour can prevent the strip deviation to some degree. In terms of prevention ability, double- taper roller is the strongest, single-taper roller and crown roller are less stronger; and more roller contour values raise the prevention ability. Accordingly, optimization method was applied to continuous annealing furnace, and it largely reduced accidents such as strip break and limited speed that are caused by the deviation.

关键词： strip deviation continuous annealing furnace dynamic simulation roller contour

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Progress and Prospects of Hydrogen Production: Opportunities and Challenges

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Journal of Electronic Science and Technology 2021年第2期19卷 97-118页

作者： Bing Zhang Sui-Xin Zhang rui yao Yong-Hong Wu Jie-Shan Qiu School of Petrochemical Engineering Shenyang University of TechnologyLiaoyang 111003 College of Chemical Engineering Beijing University of Chemical TechnologyBeijing 100029

This study presents an overview of the current status of hydrogen production in relation to the global requirement for energy and ***,it symmetrically outlines the advantages and disadvantages of various production routes including fossil fuel/biomass conversion,water electrolysis,microbial fermentation,and photocatalysis(PC),in terms of their technologies,economy,energy consumption,and *** the characteristics of hydrogen energy and the current infrastructure issues,it highlights that onsite production is indispensable and convenient for some special ***,it briefly summarizes the current industrialization situation and presents future development and research directions,such as theoretical research strengthening,renewable raw material development,process coupling,and sustainable energy use.

关键词： Electrolysis fermentation hydrogen production photocatalysis(PC) process integration renewable resource sustainable energy

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