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Assessing the impact of non-governmental organization’s extension programs on sustainable cocoa production and household income in Ghana

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Journal of Integrative Agriculture 2021年第10期20卷 2820-2836页

作者： Sonny Gad ATTIPOE cao jian-min Yaa OPOKU-KWANOWAA Frank OHENE-SEFA College of Economics and Management Jilin Agricultural UniversityChangchun 130118P.R.China ministry of Food and Agriculture Department of EconomicsAccra 183Ghana College of Resources and Environment Sciences Jilin Agricultural UniversityChangchun 130118P.R.China Ghana Cocoa Board Warehousing and Port OperationsAccra 1017Ghana

Globally,cocoa is famous for the production of chocolates and ***,it also serves as a source of raw material for the manufacturing of high-quality cosmetic and pharmaceutical products. Due to its high demand,cocoa is regarded as a major commodity for poverty alleviation in deprived cocoa farming communities. Government has therefore instigated relevant measures to address issues facing the sector by investing in extension programs. These programs act as information dissemination tools for teaching modern farming technologies and enhancing learning among farmers. This study highlighted the effects of the Cocoa Life Project (CLP) by Cooperative for Assistance and Relief Everywhere (CARE) International on farm productivity and income of 200 cocoa farmers in three districts of the Eastern Region,Ghana. Regression on covariates,Heckman’s treatment effects model,and propensity scores were used to test the robustness of the estimates. A positive association between extension program participation,farm productivity,and household income was discovered. Specifically,after correcting for selection bias,the estimated results of the Heckman’s model showed that the extension program significantly increased participating farmers’ cocoa yield by 14.3%. The effects on total farm income showed a significant increase of 25.1 and 42.9%,respectively from regression on propensity scores and the Heckman’s model. Across all three models,program participation led to an increase in total household income by 46.1,31.7,and 69.3%,respectively. Other variables such as farming characteristics,institutional and demographic factors affected farmers’ income,depending on the estimation method used. This study reiterated the supporting role played by extension programs in enhancing cocoa production and increasing household income in Ghana. Conclusively,government and development partners should invest in extension programs by providing enough logistics,training qualified agents,and creat

关键词： cocoa extension Heckman’s model regression on propensity scores smallholders

膜下滴灌不同灌水下限对花生生长发育的影响及DMA数字模型构建

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辽宁农业科学 2024年第1期 1-7页

作者：张振子孙翔龙曹敏建冯良山沈阳农业大学辽宁沈阳110866 辽宁省农业科学院辽宁沈阳110161

探究辽西地区花生膜下滴灌最佳灌溉制度,建立以有效积温为自变量的不同灌水下限花生干物质积累动态模型,以期为花生高产节水节效栽培管理提供参考依据。采用大田试验以花生白沙1016为试验材料,设置4个灌水处理,雨养处理(CK)、W50、W60、... 详细信息

探究辽西地区花生膜下滴灌最佳灌溉制度,建立以有效积温为自变量的不同灌水下限花生干物质积累动态模型,以期为花生高产节水节效栽培管理提供参考依据。采用大田试验以花生白沙1016为试验材料,设置4个灌水处理,雨养处理(CK)、W50、W60、W70(灌水下限分别为田间持水率的50%、60%、70%),通过观测花生株高、LAI和干物质积累量(DMA)变化,分析不同灌水下限对花生生长发育的影响,并建立基于有效积温为自变量,DMA为因变量的花生生长动态模型。结果表明:花生在花针期、结荚期的生长速度较快,对水分的敏感度较高,生育后期的生长速度较慢,W70处理较其他处理的花生株高、LAI和DMA有显著的提高,其产量最高达到5 181.81 kg/hm^(2)、水分利用效率最大为1.79 kg/m3。所以田间持水率70%为该地区膜下滴灌条件下花生最适宜的灌水参数,并建立了其基于归一化的有效积温为自变量的相对DMA预测的Gompertz方程:■。

关键词：膜下滴灌灌水花生生长发育水分利用效率数字模型

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融合标尺信息的足迹性别检验方法

淮阴师范学院学报（自然科学版） 2024年第2期23卷 114-120页

作者：曹俭民祁麟张一平张飞周逸阳江苏省太湖疗养院信息科江苏无锡214000 江苏警官学院刑事科学技术系江苏南京210031 江苏警官学院计算机信息与网络安全系江苏南京210031

提出了一种融合标尺信息的足迹性别检验方法.该方法采用Sobel算子得出图像中的标尺和足迹位置,基于位置信息提取足迹和标尺的全局和局部特征进行特征融合,将标尺的比例信息作为度量足迹的一部分来预测足迹性别.该研究在标准足迹检验数... 详细信息

提出了一种融合标尺信息的足迹性别检验方法.该方法采用Sobel算子得出图像中的标尺和足迹位置,基于位置信息提取足迹和标尺的全局和局部特征进行特征融合,将标尺的比例信息作为度量足迹的一部分来预测足迹性别.该研究在标准足迹检验数据集上进行了实证比较,预测准确率93.2%,比基准方法提高了2.5%.同时,消融实验表明,融合标尺信息是提高预测准确率的关键性因素.

关键词：足迹卷积神经网络物证检验性别预测

Decreased AKAP4/PKA signaling pathway in high DFI sperm affects sperm capacitation

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Asian Journal of Andrology 2024年第1期26卷 25-33页

作者： Kun Zhang Xiu-Hua Xu jian Wu Ning Wang Gang Li Gui-min Hao Jin-Feng cao Hebei Key Laboratory of Infertility and Genetics Department of Reproductive MedicineSecond Hospital of Hebei Medical UniversityShijiazhuang 050000China Department of Reproductive Medicine Affiliated Hospital of Xuzhou Medical UniversityXuzhou 221000China Department of Neurology The 980th Hospital of the People's Liberation Army Joint Logistics Support Force(Bethune International Peace Hospital)Shijiazhuang 050000China.

The sperm DNA fragmentation index(DFI)is a metric used to assess DNA fragmentation within *** in vitro fertilizationembryo transfer(IVF-ET),high sperm DFI can lead to a low fertilization rate,poor embryo development,early miscarriage,etc.A kinase anchoring protein(AKAP)is a scaffold protein that can bind protein kinase A(PKA)to subcellular sites of specific substrates and protects the biophosphorylation *** protein antigen 17(SPA17)can also bind to *** study intends to explore the reason for the decreased fertilization rate observed in high sperm DFI(H-DFI)patients during *** addition,the study investigates the expression of AKAP,protein kinase A regulatory subunit(PKARIl),and SPA17 between H-DFI and low sperm DFI(L-DFI)***17 at the transcriptional level is abnormal,the translational level increases in H-DFI patients,and the expression of AKAP4/PKARIl protein decreases.H,O,has been used to simulate oxidative stress damage to spermatozoa during the formation of sperm *** indicates that H,O,increases the expression of sperm SPA17 protein and suppresses AKAP4/PKARIl protein *** processes inhibit sperm capacitation and reduce acrosomal *** culture data and IVF outcomes have been *** H-DFI group has a lower fertilization ***,the results indicate that the possible causes for the decreased fertilization rate in the H-DFI patients have included loss of sperm AKAP4/PKARIl proteins,blocked sperm capacitation,and reduced occurrence of acrosome reaction.

关键词： AKAP PKA SPA17 sperm capacitation sperm DNA fragmentation index

3D Road Network Modeling and Road Structure Recognition in Internet of Vehicles

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Computer Modeling in Engineering & Sciences 2024年第2期138卷 1365-1384页

作者： Dun cao Jia Ru jian Qin Amr Tolba Jin Wang min Zhu College of Computer and Communication Engineering Changsha University of Science and TechnologyChangsha410114China Department of Computer Science Community CollegeKing Saud UniversityRiyadh11437Saudi Arabia College of Information Science and Technology Zhejiang Shuren UniversityHangzhou310015China

Internet of Vehicles (IoV) is a new system that enables individual vehicles to connect with nearby vehicles,people, transportation infrastructure, and networks, thereby realizing amore intelligent and efficient transportationsystem. The movement of vehicles and the three-dimensional (3D) nature of the road network cause the topologicalstructure of IoV to have the high space and time *** modeling and structure recognition for 3Droads can benefit the description of topological changes for IoV. This paper proposes a 3Dgeneral roadmodel basedon discrete points of roads obtained from GIS. First, the constraints imposed by 3D roads on moving vehicles areanalyzed. Then the effects of road curvature radius (Ra), longitudinal slope (Slo), and length (Len) on speed andacceleration are studied. Finally, a general 3D road network model based on road section features is *** paper also presents intersection and road section recognition methods based on the structural features ofthe 3D road network model and the road features. Real GIS data from a specific region of Beijing is adopted tocreate the simulation scenario, and the simulation results validate the general 3D road network model and therecognitionmethod. Therefore, thiswork makes contributions to the field of intelligent transportation by providinga comprehensive approach tomodeling the 3Droad network and its topological changes in achieving efficient trafficflowand improved road safety.

关键词： Internet of vehicles road networks 3D road model structure recognition GIS

Force-position collaborative optimization of rope-driven snake manipulator for capturing non-cooperative space targets

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CHINESE JOURNAL OF AERONAUTICS 2024年第9期37卷 369-384页

作者： Li, Xiaofeng Tian, jian Wei, Cheng cao, Xibin Harbin Inst Technol Sch Astronaut Harbin 150001 Peoples R China China Acad Space Technol Beijing Inst Spacecraft Syst Engn Beijing 100094 Peoples R China

With the rapid development of space activities, non-cooperative space targets increase swiftly, such as failed satellites and upper stages, threating normal spacecrafts seriously. As there are some problems in the capture process, such as excessive collision and fast tumbling of targets, manipulator with redundant Degrees of Freedom (DOFs) can be used to improve the compliance and therefore solve these problems. The Rope-Driven Snake Manipulator (RDSM) is a combination of hyper-redundant DOFs and better compliance, and therefore it is suitable for capturing mission. In this paper, a snake manipulator mechanism is designed, and the complete kinematic model and system dynamic model considering RDSM, target and contact is established. Then, to obtain the configuration of joint with hyper-redundant DOFs, an improved motion dexterity index is proposed as the joint motion optimization target. Besides, the force-position collaborative optimization index is designed to adjust active stiffness, and the impedance control method based on the modified index is used to capture the space target. Finally, the proposed force-position collaborative optimization method is verified by virtual prototype co-simulation. The results demonstrate that based on the proposed method, the collision force is reduced by about 25% compared to normal impedance control, showing higher safety. (c) 2024 Production and hosting by Elsevier Ltd. on behalf of Chinese Society of Aeronautics and Astronautics. This is an open access article under the CC BY-NC-ND license (http://***/ licenses/by-nc-nd/4.0/).

关键词： Capturing non-cooperative space targets Rope-driven snake manipu- lator Force-position collaborative optimization Redundant degrees of free- dom Active stiffness adjustment DUAL-ARM SPACE IMPEDANCE CONTROL ROBOT DEXTERITY INDEX

The expression of p38MAPK, NFκB, TNF-α in rats with exercise and the effects of procyanidines

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The expression of p38MAPK, NFκB, TNF-α in rats with exerci...

Variability Analysis for a Two-station Queueing Network in Heavy Traffic with Arrival Processes Driven by Queues

中国生物化学与分子生物学会2016年全国学术会议

作者： Wang Can cao jian-min Beijing Sport University

Purpose:The aim of the study was to investigate the expression of mitogen activated protein kinase p38(p38MAPK),nuclear transcription factor kappa B(NFκB)and tumor necrosis factor-α(TNF-α)in rats with high intensity exercise,and the effects of ***:With random number table,40 SPF SD eight-week rats were divided into 4 groups as follows:the

关键词： p38MAPK NFκB TNF-α IL-6 procyanidines

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Acta Mathematicae Applicatae Sinica 2024年第2期40卷 445-466页

作者： jian cao Yong-jiang GUO Kai-ming YANG School of Science Beijing University of Posts and TelecommunicationsBeijing 100876China

The law of the iterated logarithm(LIL)for the performance measures of a two-station queueing network with arrivals modulated by independent queues is developed by a strong approximation *** convenience,two arrival processes modulated by queues comprise the external system,all others are belong to the internal *** is well known that the exogenous arrival has a great influence on the asymptotic variability of performance measures in *** the considered queueing network in heavy traffic,we get all the LILs for the queue length,workload,busy time,idle time and departure processes,and present them by some simple functions of the primitive *** LILs tell us some interesting insights,such as,the LILs of busy and idle times are zero and they reflect a small variability around their fluid approximations,the LIL of departure has nothing to do with the arrival process,both of the two phenomena well explain the service station’s situation of being busy all the *** external system shows us a distinguishing effect on the performance measures:an underloaded(overloaded,critically loaded)external system affects the internal system through its arrival(departure,arrival and departure together).In addition,we also get the strong approximation of the network as an auxiliary result.

关键词： two-station queueing network the law of the iterated logarithm(LIL) strong approximation fluid approximation

Two-layer Lagrange-based relay network topology and trajectory design for solar system explorations

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Science China(Information Sciences) 2024年第6期67卷 342-358页

作者： Jun cao jian JIAO Hao LIU Rongxing LU Qinyu ZHANG Guangdong Provincial Key Laboratory of Aerospace Communication and Networking Technology Harbin Institute of Technology (Shenzhen) Faculty of Computer Science (FCS) University of New Brunswick

Exploration targeting outer planets and even the edge of the solar system is an emerging direction for the deep-space exploration in the next decades. To address this challenge, a novel two-layer Lagrangebased relay network topology is proposed in this study. Specifically, we utilize the Sun-Mars and Sun-Saturn Lagrange points(LPs) L4 and L5 to build a two-layer backbone relay network, which ensures continuous and high-efficiency communication capability for the exploration of the solar system. Furthermore, we utilize the planetary gravity assist and design the transfer trajectory of backbone relays with the help of planetary celestial body motion equations and Kepler's laws. Moreover, we conduct link budget analysis for multihop relay transmission under Gamma-Gamma distribution, shadowed Rician fading, and additive white Gaussian noise channels in several typical exploration scenarios and validate that the LP relays can effectively support future deep-space exploration missions.

关键词： deep-space communication Lagrangian points backbone relay network transfer trajectory relay selection