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Establishment and verification of labor demand estimation model in planting industry

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International Journal of Agricultural and Biological Engineering 2017年第6期10卷 86-93页

作者： Xu Bing wang fulin wang Jiquan Zhao Shengxue College of Engineering Northeast Agricultural UniversityHarbin 150030China

In view of the poor precision of the theoretical model of labor demand estimation,it is difficult to estimate and predict the actual production problems accurately.Based on the actual production conditions and the relationship between the degree of mechanization of planting and the demand of labor force,this study established an estimation model for the labor demand of planting industry considering the factors of planting structure and mechanization degree.In order to ensure high reliability of data,the method of checking out abnormal data was adopted to obtain the cultivated land area index when the mechanization degree is from 0 to 100%.Taking Suihua region(Heilongjiang Province,China)as an example,the theory of the research was analyzed and applied.This study accessed to the data of cultivated land area per labor can afford when the mechanization level in Suihua area were 0 and 100%respectively through the investigation,and the average cultivated land area data of each labor force in two cases were sorted out and the abnormal data were eliminated at the same time.Finally,using the derived model,the data obtained and the mechanization level and cultivated land area of Suihua in the future,the labor demand amount in Suihua area from 2015 to 2019 were predicted.The model established in this study can be used to calculate the quantity of both current labor demand in planting industry and the labor demand in the various moments in the future through forecasting the future mechanization level and cultivated area which are the two main factors influencing the quantity of labor demand in planting structure.

关键词： planting industry labor estimation model case verification forecast evaluation

Improved estimation model and empirical analysis of relationship between agricultural mechanization level and labor demand

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International Journal of Agricultural and Biological Engineering 2016年第2期9卷 48-53页

作者： wang fulin Zhao Shengxue Fu Xiaoming College of Engineering Northeast Agriculture UniversityHarbin 150030China

The research on the relationship between mechanization level in planting industry and labor demand was carried out based on the present literatures.The former estimation model of labor demand in planting industry was established without analyzing the effects of planting structure on labor demand in planting industry.The purpose of the research is to develop and perfect the theory of estimating both labor demand and rural surplus labor in planting industry,then to provide some theoretical references for scientific estimation.The model established in this research can be used to calculate not only the amount of current labor demand,but also the demand in the various moment of future according to forecasted mechanization level and cultivated areas.Furthermore,it was explored how to obtain the indexes of cultivated areas,mechanization level and the average cultivated area that each labor can burden when the mechanization level is 0 and 100%.According to statistics principle,the methods of inspection to eliminate abnormal data and data processing were given in order to make the data more credible.Finally,an example was presented for demonstration purposes.

关键词： agricultural mechanization level planting industry labor demand estimation model data acquisition crop production

基于改进实数遗传算法的桑叶采摘机结构参数优化

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中国农机化学报 2024年第1期45卷 14-20,53页

作者：王吉权宋丽宋豪豪张攀利王福林东北农业大学工程学院哈尔滨市150030

针对遗传算法在求解桑叶采摘机结构优化问题时容易陷入局部最优和求解精度低等问题,提出一种改进实数遗传算法。首先是给出一种基于序的组合适应度函数的轮盘赌选择算子,该算子在轮盘赌的基础上,通过一个自适应变化的参数在两种适应度... 详细信息

针对遗传算法在求解桑叶采摘机结构优化问题时容易陷入局部最优和求解精度低等问题,提出一种改进实数遗传算法。首先是给出一种基于序的组合适应度函数的轮盘赌选择算子,该算子在轮盘赌的基础上,通过一个自适应变化的参数在两种适应度函数中选择一个,再去计算适应度值;然后设计一种基于方向的改进启发式交叉算子,该算子既保留两个父代个体中较优个体对子代个体的影响,又增加种群中最优个体对子代个体的影响,提高交叉产生有潜力子代的可能性。接着将改进算法应用于摇杆式桑叶采摘机的优化参数设计中,通过与其他算法作仿真对比试验验证算法的优越性,获得采摘机最优参数组合:行走结构速度为24 mm/s、拨动结构角速度为1.2 rad/s、采摘结构速度为440 mm/s,并由运行结果可知整机性能与优化前相比提高13%。最后用优化得到的参数组合进行实地试验,结果显示桑叶采摘机性能提升10.9%,误差较小为2.1%。可见,所提改进实数遗传算法是优化采摘机参数的一种有效算法。

关键词：桑叶采摘机结构优化实数遗传算法轮盘赌选择启发式交叉算子

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拖拉机转向梯形优化设计研究

农机化研究 2024年第5期46卷 235-239,246页

作者：王茉孙盛智宋莹莹卢珊王福林东北农业大学工程学院黑龙江哈尔滨150030 东北农业大学经济管理学院黑龙江哈尔滨150030 大连大学经济管理学院辽宁大连116622

在现有文献研究的基础上,对拖拉机转向梯形优化设计问题进行了进一步深入研究,提出了一种以拖拉机转弯半径最小为目标的优化设计方法。以减小拖拉机最小转弯半径为目标,以转向臂长度、梯形底角和传动角为约束条件,通过推导给出了相关的... 详细信息

在现有文献研究的基础上,对拖拉机转向梯形优化设计问题进行了进一步深入研究,提出了一种以拖拉机转弯半径最小为目标的优化设计方法。以减小拖拉机最小转弯半径为目标,以转向臂长度、梯形底角和传动角为约束条件,通过推导给出了相关的数学公式,建立了拖拉机转向梯形优化设计模型。针对模型的求解,给出了一种求解该问题的改进实数遗传算法。最后,对转向梯形优化设计模型进行了实例计算,取得了良好的结果,优化后的拖拉机转弯半径较优化前减小了0.1039m。

关键词：拖拉机转向梯形最小转弯半径实数遗传算法

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电位滴定法测定土壤中水溶性氯离子

生物化工 2024年第2期10卷 134-137页

作者：赖波王福林四川省冶金地质勘查局六0五大队四川眉山620860

建立了电位滴定法测定土壤中水溶性氯离子含量的方法。通过对浸提温度、pH值、干扰消除等条件进行详细试验,确定最佳的测定条件:土样于25℃下加水振荡后,加入适量硝酸消除碳酸根、硫离子的影响,使pH在3.0~5.0。此方法土壤水溶性氯离子... 详细信息

建立了电位滴定法测定土壤中水溶性氯离子含量的方法。通过对浸提温度、pH值、干扰消除等条件进行详细试验,确定最佳的测定条件:土样于25℃下加水振荡后,加入适量硝酸消除碳酸根、硫离子的影响,使pH在3.0~5.0。此方法土壤水溶性氯离子的检出限为0.002 g/kg,精密度(RSD,n=7)为1.7%~4.8%,准确度(RE)为-0.3%~1.5%。方法准确可靠,满足《第三次全国土壤普查全程质量控制技术规范》要求。本方法克服了传统滴定法对于色度严重的样品终点难以判断的缺点,具有普遍适用性,易于推广使用。

关键词：电位滴定土壤水溶性氯离子

38CrMoAl渗氮钢微晶刚玉砂轮摆线磨削工艺试验研究

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工具技术 2024年第4期58卷 49-53页

作者：周辉蔡云辉王熔李希扬黄向明王伏林汤涛湖南星途航空航天器制造有限公司湖南省株洲市412007 湖南大学机械与运载工程学院

在实际磨削38CrMoAl渗氮钢过程中,存在磨削烧伤情况。本文分别采用白刚玉砂轮和微晶刚玉砂轮磨削38CrMoAl渗氮钢,对比研究了不同磨料类型刚玉砂轮对磨削力和表面粗糙度的影响规律。试验结果表明:相较于白刚玉砂轮,微晶刚玉砂轮磨削时磨... 详细信息

在实际磨削38CrMoAl渗氮钢过程中,存在磨削烧伤情况。本文分别采用白刚玉砂轮和微晶刚玉砂轮磨削38CrMoAl渗氮钢,对比研究了不同磨料类型刚玉砂轮对磨削力和表面粗糙度的影响规律。试验结果表明:相较于白刚玉砂轮,微晶刚玉砂轮磨削时磨削力降低了14.2%。基于正交试验方法,通过微晶刚玉砂轮平面磨削试验,探究了磨削工艺参数对磨削力和工件表面粗糙度的影响。结果分析表明:磨削深度对磨削力影响最大,其次是工件进给速度和砂轮转速;对于工件表面粗糙度而言,工件进给速度的影响最大,其次是砂轮速度和磨削深度。最终采用微晶刚玉砂轮对38CrMoAl渗氮钢齿轮样件进行批次加工,结果显示无磨削烧伤发生,且磨削表面质量得到了显著提高。

关键词：渗氮钢齿轮微晶刚玉砂轮磨削力表面粗糙度

Effect of Natural Zeolite on Pore Structure of Cemented Uranium Tailings Backfill

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Journal of Renewable Materials 2023年第3期11卷 1469-1484页

作者： fulin wang Xinyang Geng Zhengping Yuan Shijiao Yang School of Resource&Environment and Safety Engineering University of South ChinaHengyang421001China

The use of some environmental functional minerals as backfill-modified materials may improve the leaching resistance of cemented uranium tailings backfill created from alkali-activated slag(CUTB),but these materials may participate in the hydration reaction of the cementitious materials,which could have a certain impact on the pore structure of the CUTB,thus affecting its mechanical properties and leaching resistance.In this paper,natural zeolite is selected as the backfill-modified material,and it is added to alkali-activated slag paste(AASP)and CUTB in cementitious material proportions of 4%,8%,12%,and 16%to prepare AASP mixtures and CUTB mixtures containing environmental functional minerals.After the addition of natural zeolite,the porosity of the CUTB generally increases,but when the content is 4%,the porosity decreases to 22.30%.The uniaxial compressive strength(UCS)of the CUTB generally decreases,but the decrease is the smallest when the content is 4%,and the UCS is 12.37 MPa.The addition of natural zeolite mainly reduces the number of fine pores in the CUTB,but the pores with relaxation times T_(2)of greater than 10 ms account for about 10%of the total pores,and there are a certain number of large pores in the CUTB.The main product of alkali-activated slag is calcium(alumino)silicate hydrate(C-(A)-S-H gel).When natural zeolite is added,the hydration products develop towards denser products with a high degree of polymerization and the formation of low polymerization products is reduced.This affects the internal fracture pores of the hydration products and the interface pores of the CUTB,has an irregular effect on the pore characteristics of the CUTB,and influences the UCS.

关键词： Pore structure cemented backfill natural zeolite uranium tailings LF-NMR

电感耦合等离子体发射光谱法同时测定土壤中硼和硫

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化学分析计量 2024年第3期33卷 59-64页

作者：王福林赖波邢智钟郑飞四川省冶金地质勘查局六0五大队四川眉山620860

建立了同时测定土壤中硼和硫元素含量的封闭溶样-电感耦合等离子体发射光谱法。以HCl-HNO3-HF-H3PO4混合酸为消解液,经封闭溶样进行样品消解。对消解体系、溶样时间和赶酸温度等条件进行了优化,并配制添加磷酸的标准工作溶液进行基体匹... 详细信息

建立了同时测定土壤中硼和硫元素含量的封闭溶样-电感耦合等离子体发射光谱法。以HCl-HNO3-HF-H3PO4混合酸为消解液,经封闭溶样进行样品消解。对消解体系、溶样时间和赶酸温度等条件进行了优化,并配制添加磷酸的标准工作溶液进行基体匹配,成功消除了基体效应带来的系统误差。采用了氩气吹扫光室,避免空气以及水蒸气对紫外光的吸收,增强待测元素硫的强度,采用电感耦合等离子体发射光谱法同时测定土壤中的全硼和全硫。硼、硫的质量浓度在0~10 mg/L范围内与光谱强度线性关系良好,线性相关系数均大于0.999 1,硼的检出限为0.7 mg/kg,硫的检出限为2.5 mg/kg。硼、硫测定结果的相对标准偏差分别为1.0%~5.7%和1.7%~7.9%(n=7),相对误差分别为-10.0%~6.2%和-7.5%~10.6%。该方法操作简便、分析快速,满足第三次全国普查全程质量控制技术规范要求,可用于土壤中全硼和全硫的分析。

关键词：封闭溶样土壤电感耦合等离子体发射光谱硼硫磷酸

Solution for Distributed Model of Groundwater System with PCG2 for Naolihe Basin in Sanjiang Plain

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Journal of Northeast Agricultural University(English Edition) 2009年第1期16卷 59-63页

作者： GUO Longzhu wang fulin PENG Shengmin College of Agriculture Northeast Agricultural University Harbin 150030 China State Key Laboratory of Hydrology-Water Resources and Hydraulic Engineering Hohai University Nanjing 210098 China Engineering College Northeast Agricultural University Harbin 150030 China

PCG2 （Preconditioned Conjugate-Gradient Method 2）, the most popular mothod used in groundwater field, was used to solve the distributed model of large-scale groundwater system. Its principle and effect was analyzed mathematically, and verified by some specific examples. Numerical results acquired by PCG2 are accurate, it demonstrates that PCG2 is effective on methodology itself and man-ralated operation. So PCG2 is worthy of popularizing in the area of groundwater system for numerical analysis.

关键词： PCG2 groundwater distributed model accuracy