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Are vulnerable farmers more easily influenced?Heterogeneous effects of Internet use on the adoption of integrated pest management

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Journal of Integrative Agriculture 2023年第10期22卷 3220-3233页

作者： LI Kai jin Yu ZHOU jie-hong School of Economics Qufu Normal UniversityRizhao 276826P.R.China China Academy for Rural Development Zhejiang UniversityHangzhou 310058P.R.China School of Public Affairs Zhejiang UniversityHangzhou 310058P.R.China

The Internet is believed to bring more technological dividends to vulnerable farmers during the green agriculture ***,this is different from the theory of skill-biased technological change,which emphasizes that individuals with higher levels of human capital and more technological endowments benefit *** study investigates the effects of Internet use on farmers'adoption of integrated pest management(IPM),theoretically and empirically,based on a dataset containing 1015 farmers in China's Shandong *** exploring the perspective of rational inattention,the reasons for the heterogeneity of the effects across farmers with different endowments,i.e.,education and land size,are *** potential endogeneity issues are addressed using the endogenous switching probit *** results reveal that:(1)although Internet use significantly positively affects farmers'adoption of IPM,vulnerable farmers do not benefit more from *** selection bias leads to an overestimation of technological dividends for vulnerable farmers;(2)different sources of technology information lead to the difference in the degree of farmers'rational inattention toward Internet information,which plays a crucial role in the heterogeneous effect of Internet use;and(3)excessive dependence on strong-tie social network information sources entraps vulnerable farmers in information cocoons,hindering their ability to reap the benefits of Internet use ***,it is essential to promote services geared towards elderly-oriented Internet agricultural technology information and encourage farmers with strong Internet utilization skills to share technology information with other farmers actively.

关键词： Internet use IPM vulnerable farmers technological dividends endogenous switching probit model

Optimal operation of multi-storage tank multi-source system based on storage policy

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2010年第8期11卷 571-579页

作者： Hai-en FANG jie ZHANG jin-liang GAO School of Municipal and Environment Engineering Harbin Institute of Technology Harbin 150090 China

A two-stage method is developed to solve a new class of multi-storage tank multi-source (MTMS) systems. In the first stage, the optimal storage policy of each tank is determined according to the electricity tariff, and the ground-level storage tank is modeled as a node. In the second stage, the genetic algorithm, combined with a repairing scheme, is applied to solve the pump scheduling problem. The objective of the pump scheduling problem is to ensure that the required volume is adequately provided by the pumps while minimizing the operation cost (energy cost and treatment cost). The decision variables are the settings of the pumps and speed ratio of variable-speed pumps at time steps of the total operational time horizon. A mixed coding methodology is developed according to the characteristics of the decision variables. daily operation cost savings of approximately 11% are obtained by application of the proposed method to a pressure zone of S. Y. water distribution system (WDS), China.

关键词： Multi-storage tank system Storage policy Genetic algorithm Repairing scheme Pump scheduling

Record-breaking rainfall over the middle reaches of the Yangtze River in August 2021: Sub-seasonal perspective and its predictability

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Advances in Climate Change Research 2022年第6期13卷 826-834页

作者： Li GUO jie WU jin-Qing ZUO Climate Studies Key Laboratory National Climate CenterChina Meteorological AdministrationBeijing 100081China Collaborative Innovation Center on Forecast and Evaluation of Meteorological Disasters(CIC-FEMD) Nanjing University of Information Science&TechnologyNanjing 210066China

An extremely heavy rainfall cluster was observed over the middle reaches of the Yangtze River(MYR)in August 2021,breaking the historical record since 1981 and causing severe *** controlling circulation regime and possible predictability sources of the un-expected rainfall are still unclear,especially from a sub-seasonal *** results show that the successive heavy rainfall events in August 2021 had significant intraseasonal oscillations for 10-24 d and 30-60 d,and they were synergistically influenced by tropical and extra-tropical circulation *** all,the East Asia-Pacific teleconnection pattern(EAP)turned into a negative phase in late July and maintained throughout August,providing favorable background conditions for the northward transport of tropical water vapor and the southward intrusion of cold air from mid-high *** 30-60-d oscillation of precipitation was dominated by the first mode of boreal summer intraseasonal oscillation(BSISO1,with 30-60-d period),which strengthened the tropical moisture transport,while the quasi-biweekly oscillation of the western Pacific subtropical high and the anomalous mid-latitude cyclone of EAP intensified the precipitation on the scale of 10-24 *** addition,the second mode of BSISO(BSISO2,with 10-30-d period)may also intensify the 10-24-d precipitation in late *** forecast leading time of the S2S models for the persistent heavy rainfall in August 2021 was basically 1-2 weeks,while the EAP and BSISO1 were revealed as the main predictable sources of the abnormal rainfall *** results highlight the importance of superposition of different intraseasonal oscillations in forming the extreme rainfall event and demonstrate a potential chance to enhance the prediction skill of extreme event if the ensemble members in S2S models could be reasonably selected according to their performances on key predictability sources.

关键词： Heavy rainfalls Intraseasonal oscillation Predictability East Asia-Pacific teleconnection pattern Boreal summer intraseasonal oscillation

Polyethylene Oxide-Coated Electrospun Polyimide Fibrous Seperator for High-Performance Lithium-Ion Battery

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Journal of Materials Science & Technology 2016年第3期32卷 200-206页

作者： Xingxing Liang Ying Yang Xin jin jie Cheng Department of Electrical Engineering Tsinghua University Beijing 100084 China Beijing Smart China Energy Internet Research Institute Beijing 100176 China State Key Lab. of Power System Tsinghua University Beijing 100084 China Zhangjiagang Smartgrid Research Institute Zhangjiagang 215600 China Research Institute of Chemical Defense Beijing 100191 China

A polyethylene oxide （PEO）-coated polyimide （PI） membrane was prepared by electrospinning method followed by a dip-coating and drying process for high-performance lithium-ion batteries （LIB）. 8emicrystal PEO was covered on the surface of the fibers and partially enmeshed in PI matrix, which formed unique porous structures. The pores with an average size of 4.1 μm and a porosity of 90% served as ion transport channels. Compared with the cell with Celgard 2400 membrane, the half-cell using PEO-coated P1 membrane as a separator exhibits excellent electrochemical performance both at room temperature and at low temperature. The electrolyte uptaking rate of PEO-coated PI membrane was 170% and the ionic conductivity was 3.83 × 10^-3 S cm^-1. PEO-coated PI membrane possessed 5.3 V electrochemical window. The electrode-electrolyte interfacial resistance was 62.4 Ω. The capacity retention ratios with PEO- coated PI membrane were 86.4% at 5 C and 73.5% at 10 C at 25 ℃ and 75% at 5 C at 0 ℃. Furthermore, the cell using the separator demonstrates excellent capacity retention over cycling. These advanced characteristics would boost the application of the PEO-coated PI membrane for high-power lithium ion battery.

关键词： Lithium-ion batteries Electrospinning Polyimide Polyethylene oxide Low temperature

Attitude control of a rigid spacecraft with one variable-speed control moment gyro

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Acta Mechanica Sinica 2013年第5期29卷 749-760页

作者： Hai-Chao Gui Lei jin Shi-jie Xu School of Astronautics Beihang University

Nonlinear controllability and attitude stabilization are studied for the underactuated nonholonomic dynamics of a rigid spacecraft with one variable-speed control moment gyro （VSCMG）, which supplies only two internal torques. Nonlinear controllability theory is used to show that the dynamics are locally controllable from the equilibrium point and thus can be asymptotically stabilized to the equilibrium point via time-invariant piecewise continuous feedback laws or time-periodic continuous feedback laws. Specifically, when the total angular momentum of the spacecraft-VSCMG system is zero, any orientation can be a controllable equilib- rium attitude. In this case, the attitude stabilization problem is addressed by designing a kinematic stabilizing law, which is implemented through a nonlinear proportional and deriva- tive controller, using the generalized dynamic inverse （GDI） method. The steady-state instability inherent in the GDI con- troller is elegantly avoided by appropriately choosing control gains. In order to obtain the command gimbal rate and wheel acceleration from control torques, a simple steering logic is constructed to accommodate the requirements of attitude sta- bilization and singularity avoidance of the VSCMG. Illustrative numerical examples verify the efficacy of the proposed control strategy.

关键词： Attitude control inverse Nonholonomic system Generalized dynamic Small-time local controlla- bility - Stabilization Variable-speed control moment gyro

循环荷载作用下含倾斜单裂隙砂岩力学响应特征及渗流演化规律

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岩土力学 2025年第1期46卷 199-212页

作者：唐劲舟唐文豪杨科赵延林刘钦节段敏克谭哲安徽理工大学矿业工程学院安徽淮南232001 安徽理工大学安徽省关闭废弃矿井资源开发利用工程研究中心安徽淮南232001 合肥综合性国家科学中心能源研究院安徽合肥230031 湖南科技大学资源环境与安全工程学院湖南湘潭411201

为了研究循环荷载对裂隙岩体力学破坏特征和渗流演化规律的影响,开展轴压和孔压低频多次循环加卸载条件下含倾斜粗糙单裂隙砂岩的应力-渗流耦合试验。结果表明:在应力的作用下,岩样沿预制裂隙面发生相对滑移,裂隙表面凸起在滑移过程中... 详细信息

为了研究循环荷载对裂隙岩体力学破坏特征和渗流演化规律的影响,开展轴压和孔压低频多次循环加卸载条件下含倾斜粗糙单裂隙砂岩的应力-渗流耦合试验。结果表明:在应力的作用下,岩样沿预制裂隙面发生相对滑移,裂隙表面凸起在滑移过程中发生磨损、剪断,凸起的剪断和磨损会导致加载过程中应力的小幅跌落,也是导致流量在压缩过程中发生波动的主要原因;对于含倾斜单裂隙的试样,其强度主要取决岩块是否沿预制裂隙面产生滑移和孔压的大小;在轴压循环加卸载过程中,裂隙岩体随着循环次数的增加产生损伤劣化,试样抵抗变形的能力变弱,表现为弹性模量非线性下降,泊松比非线性上升;孔压循环加卸载会减短衰减蠕变段的时间,在稳定蠕变阶段会减小蠕变的应变率;循环加卸载过程中流量是一个动态演化的过程,在加载初期,因为裂隙在应力的作用下发生闭合,流量呈下降趋势,随后流量随着轴压的循环加载―卸载而减小―增大;基于灰度阈值分割方法可以将裂隙的连通域和接触域较好的分离开,连通域与整个裂隙面面积相比得到的裂隙连通率Ф,最终流量随分形维数D与裂隙连通率Ф的增大呈指数级增大。

关键词：裂隙岩体循环加卸载力学特性渗流形貌表征

Material removal at atomic and close-to-atomic scale by highenergy photon:a case study using atomistic-continuum method

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Advances in Manufacturing 2022年第1期10卷 59-71页

作者： Hao-jie An jin-Shi Wang Feng-Zhou Fang State Key Laboratory of Precision Measuring Technology and Instruments Laboratory of MicroNano Manufacturing Technology(MNMT)Tianjin UniversityTianjin 300072People’s Republic of China Centre of MicroNano Manufacturing Technology(MNMTDublin) School of Mechanical and Materials EngineeringUniversity College DublinDublin 4Ireland

Extreme ultraviolet(EUV)light plays an important role in various fields such as material characterization and semiconductor *** is also a potential approach in material fabrication at atomic and close-to-atomic ***,the material removal mechanism has not yet been fully *** paper studies the interaction of a femtosecond EUV pulse with monocrystalline silicon using molecular dynamics(MD)coupled with a two-temperature model(TTM).The photoionization mechanism,an important process occurring at a short wavelength,is introduced to the simulation and the results are compared with those of the traditional *** processes including photoionization,atom desorption,and laser-induced shockwave are discussed under various fluencies,and the possibility of single atomic layer removal is *** show that photoionization and the corresponding bond breakage are the main reasons of atom *** method developed can be further employed to investigate the interaction between high-energy photons and the material at moderate fluence.

关键词： Extreme ultraviolet(EUV) Molecular dynamics(MD) Two-temperature model(TTM)Photoionization Atomic and close-to-atomic scale manufacturing(ACSM)

Coupling effect of micro-textured tools and cooling conditions on the turning performance of aluminum alloy 6061

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Advances in Manufacturing 2023年第4期11卷 663-681页

作者： Guo-Liang Liu jin-Tao Zheng Chuan-Zhen Huang Shu-Feng Sun Xin-Fu Liu Long-jie dai De-Xiang Wang Xiang-Yu Wang Key Lab of Industrial Fluid Energy Conservation and Pollution Control Ministry of EducationKey Lab of Industrial Fluid Energy Conservation and Pollution ControlMinistry of EducationSchool of Mechanical and Automotive EngineeringQingdao University of TechnologyQingdao266520ShandongPeople’s Republic of China State Key Laboratory of High Performance Complex Manufacturing Central South UniversityChangsha410083People’s Republic of China Key Laboratory of High-Efficiency and Clean Mechanical Manufacture(Ministry of Education) School of Mechanical EngineeringShandong UniversityJinan250061People’s Republic of China School of Mechanical Engineering Yanshan UniversityQinhuangdao066004HebeiPeople’s Republic of China Qingdao Choho Ind Co Ltd Qingdao266705ShandongPeople’s Republic of China School of Mechanical Engineering University of JinanJinan250022People’s Republic of China

Micro-texturing has been widely proven to be an effective technology for achieving sustainable ***,the performance of micro-textured tools under different cooling conditions,especially their coupling effect on machined surface integrity,was scarcely *** this paper,the non-textured,linear micro-grooved,and curvilinear micro-grooved inserts were used to turn aluminum alloy 6061 under dry,emulsion,and liquid nitrogen cryogenic cooling *** coupling effects of different micro-textures and cooling conditions on cutting force,cutting temperature,and machined surface integrity,including the surface roughness,work hardening,and residual stress,were revealed and discussed in *** indicated that the micro-grooved tools,especially the curvilinear micro-grooved tools,not only reduced the cutting force and cutting temperature,but also improved the machined surface *** addition,the micro-grooved tools can cooperate with the emulsion or liquid nitrogen to reduce the cutting force,cutting temperature,and improve the machined surface integrity generally,although the combination of emulsion cooling condition and micro-grooved tools generated negative coupling effects on cutting forces and surface work ***,the combination of curvilinear micro-grooved cutting tools and cryogenic cooling condition resulted in the lowest cutting force and cutting temperature,which generated the surface with low roughness,weak work hardening,and compressive residual stress.

关键词： Micro-grooved cutting tool Cooling condition Cutting force Cutting temperature Surface integrity

超级微波消解ICP-OES法测定宠物饲料中硫含量及与总蛋白质相关性分析

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光谱学与光谱分析 2025年第2期45卷 420-425页

作者：陈树娣李锦才陈晓燕李胜张世伟郑彦婕深圳市计量质量检测研究院广东深圳518131 国家市场监管技术创新中心(智能光电传感) 广东深圳518131

建立了超级微波消解-电感耦合等离子体发射光谱法(ICP-OES)测定宠物饲料中硫含量的新方法。系统探究了超级微波消解条件对消解液中残留碳含量(RCC)和残留酸量(RA)的影响,以这两项指标为依据,有效评估了消解效果,建立了优化微波消解条件... 详细信息

建立了超级微波消解-电感耦合等离子体发射光谱法(ICP-OES)测定宠物饲料中硫含量的新方法。系统探究了超级微波消解条件对消解液中残留碳含量(RCC)和残留酸量(RA)的影响,以这两项指标为依据,有效评估了消解效果,建立了优化微波消解条件的新策略。系统性研究了五种不同价态的硫形态对硫元素测定的影响,发现低价态硫标准物质在酸性条件下制备时,硫元素发射强度显著增强,而高价态硫标准物质在三种条件(酸性、中性和碱性)下制备时,硫元素发射强度均较稳定,为配制介质和硫标准物质的选择提供了有益的指导。研究发现,超级微波消解系统所创造的高温高压环境以及消解试剂的强氧化性条件,能有效消除低价态硫在酸性前处理条件下的发射强度增强效应。采用酸性条件配制高价态硫(SO_(4)^(2-))标准物质,并结合超级微波消解系统,能够实现宠物饲料中五种不同价态硫的准确测定。加标回收率为86.5%~108%,RSD值为1.69%~4.18%,检出限为6.2 mg·kg^(-1),与国家标准方法相比,该方法具有灵敏度高、成本低、绿色环保、工作效率高的优点。研究发现宠物饲料中硫含量与总蛋白质含量之间存在极显著正相关性(相关系数=0.819,p<0.01),可以为宠物饲料中总蛋白质含量的准确测定提供新思路和方向。

关键词：超级微波消解超级微波消解-电感耦合等离子体发射光谱(ICP-OES) 宠物饲料硫总蛋白质相关性