作物品种区域试验的试验精确度和品种比较精确度

 从精确度的基本概念出发，研究作物品种区域试验的试验精确度和品种比较精确度的指标。提出期望品种比较精确度（ＥＶＣＰ）和实现品种比较精确度（ＲＶＣＰ）的概念，给出相应精确度指标计算公式和应用实例，并利用多年历史区试资料对我国长江流域与黄河流域的棉花区域试验及试点的精确度作了调查。     

我国作物品种区域试验的精确研究

根据1982年以来我国部分作物品种区域试验的资料，对比研究棉花、小麦、水稻和玉米试验的试验精确度（EP）和品种比较精确度（VCP）。结果表明，棉花和玉米区试的EP及一年一点试验的VCP普遍低于小麦和水稻，其试验误差有待降低；棉花一点两年试验的VCP严重不足，平均低于25％，各种作物一年多点试验的VCP控制得较好，其平均均在10％以内或左右；但多年多点的试验的VCP在不同试验中差别较大，其差异主要表现在同一种作物的不同组别间。最后，针对区试中存在的精度问题，总结提出提高区精度的各种途径。     

Comparison of Statistical Models for Regional Crop Trial Analysis

Based on the review and comparison of main statistical analysis models for estimating varietyenvironment cell means in regional crop trials, a new statistical model, LR-PCA composite model was proposed, and the predictive precision of these models were compared by cross validation of an example data. Results showed that the order of model precision was LR-PCA model ＞ AMMI model ＞ PCA model ＞ Treatment Means (TM) model ＞ Linear Regression (LR) model ＞ Additive Main Effects ANOVA model. The precision gain factor of LR-PCA model was 1.55, increasing by 8.4% compared with AMMI.     

Detection Precision of Seedmeter for Large-granule Seeds

A detecting method based on machine vision was put forward to test the performance of seedmeter with corn and soybean seeds as test samples, in which MATLAB software was applied to process image data and analyze the results. The experimental results showed that the mean value of absolute error of the sowing speed for soybean was 0.004-0.68 seed · s^?1; the mean value of relative error was from 6.5% to 130%, and there were no significant differences of mean value, standard deviation and coefficient of variation of flowing seeds between manual statistics and MATLAB statistics. The machine vision method was proved to be time-saving, labor-saving and no-touching in the seedmeter precision detecting.     

南方林区森林火险精准区划方法

基于三维地理信息系统(3D GIS)技术,根据南方集体林区森林火灾的特点,以浙江省临安市为实验区,将森林火灾因子分成社会经济、林学特征、气象特征等三大类11个指标,并赋予相应的权重.在此基础上,构建3个特征向量(社会经济特征向量、林学特征向量、气象特征向量),建立了非线性数学模型——森林火险精准区划模型,并利用最小二乘法等数学方法,对模型进行了求解、优化与验证.结果表明:实验值和理论值的误差均小于0.1.该模型和实验区历史火灾发生情况基本吻合.     

四川省小麦区试品系丰产性及稳定性比较分析

[目的]分析评价区试小麦品系产量的稳定性,为选育高产、稳产小麦新品种提供依据。[方法]采用变异系数法和高稳系数法对四川省小麦区试的12个品系进行丰产性、稳定性分析。[结果]参试品系XK055-3、SW22514在2种分析方法中的估计结果均表现较好;品系川04品4、04064、04062丰产性、稳产性较差;而对照品种川麦107处于中游水平,产量中等、稳定性好。[结论]西南科技大学选育XK055-3和省农科院作物所选育SW22514属高产、稳产性苗头品系。     

单粒精播技术在花生新品种快速繁育上的应用研究

[目的]为单粒精播快繁技术在花生良种快繁上的应用提供科学依据.[方法]以吉花3号（多粒型）为研究材料,系统研究大田单粒精播节本增效高产栽培技术和大棚单粒精播高效快繁技术对花生植株性状、产量和繁殖系数的影响.[结果]两种单粒精播技术均可明显降低花生株高,增加单株结果数及饱果率,提高产量和繁殖系数,其中大棚单粒精播高效快繁技术的繁殖系数达到34.3,比常规双粒穴播提高84.5％.[结论]两种快繁技术在节种增产、提高繁殖系数上效果明显,可作为花生新品种快速蘩育的可行技术.     

采样数量和分布模式对土壤有机质空间插值精度的影响

基于北京市大兴区南部郊区平原农用地的高密度土壤样点,结合GIS和空间插值方法,对研究区的样点数据进行随机抽样生成不同数量的数据集,探讨采样点数量和分布模式对土壤有机质空间预测插值精度的影响。研究结果表明:(1)利用不同方式确定的合理采样点数量由高到低依次是插值方法的精度要求、变异函数拟合效果、正态分布法和均值及变异函数的满足小于5%相对误差;(2)变异函数拟合效果总体随着采样点数量的增加呈梯度式增强,但495点集优于825点集;相同样点分布模式下变异函数拟合效果相似;(3)相同样点集的不同插值方法预测精度存在差异,最佳插值方法不同;2272、825、115点集BEK都是最优,1485、495和83点集分别是SWT、SK和LPI最优;(4)样点间最近邻距离分布模式中P值小于0.05,插值模型对土壤有机质插值精度低;P0.05,R比率接近1,样点分布强于样点数量对插值模型对预测精度的影响;其P0.05且R比率大于1.20,各常规插值方法能得到较稳定的插值精度。     

Development and Validation of National Cotton Cultivar Registration Index Model in Yangtze River Valley

[Objective] Based on the cotton variety high yielding potential, fiber quality traits, disease resistance, and early maturity characters, a cultivar registration index model was developed to simplify the tedious calculation process in national cotton registration procedure, and thus to enhance the practical application of cultivar regis- tration index in cotton breeding ancl cotton recommending. [Method] By means of correlation analysis, partial correlation analysis and path analysis methods, the cor- relation of cotton main properties and their effects on cultivar registration index were explored using the dataset of national cotton regional trials in Yangtze River Valley during 1996-2013. The cultivar registration index model was constructed with step- wise regression statistical technique to ascertain the quantitative relationship of main characters with cultivar registration index, and the regional cotton trial dataset in 2013 was used to validate the model. [Result] Several characters with larger deter- minants to cultivar registration index were screened out,ie. lint yield increase ratio, pro-frost yield ratio, verticillium wilt index, fiber strength, fusarium wilt index and mi- cronaire value. The cultivar registration index model defined the functional relation- ship of cultivar registration index with the selected main characters, among which lint yield increase ratio, fiber strength and micronaire value contributed most to culti- var registration index. The model validation with regional cotton trials in 2013 indi- cated the root mean square error, RMSE was only 2.77, and the variation coeffi- cient was 6.77%, which confirmed the model prediction effect was quite perfect. [Conclusion] The developed cultivar registration index model was reliable enough to simulate the complicated scoring system in cultivar registration procedure, also sim- plified cotton registration process, and enhanced the practicability of the cultivar reg- istration index.     

称重法和光电法量测面积的精度分析与比较

应用称重法和光电法对图纸面积的量测精度研究。结果表明:两种方法都可达到规范要求,且简单易行,尤其是称重法可降低成本。称重法主要误差来源是剪裁走线不准;光电法主要误差来源是图纸染色不均匀。     

样点数量对林区土壤水分动态测定精度的影响

为了保证土壤水分动态的测定精度对森林土壤水分变异性进行了研究,以合理确定样点数。结果表明,森林土壤水分的变异主要来源于林地土壤条件的变化及树冠对降雨的不均匀截留,且随季节而变化。在研究地区,土壤水分的变异系数在6～20％,要使土壤水分动态的测定精度高于0.90,测定重量含水量及容重的样点数须分别不少于10个及8个。对林木分布不均或土壤条件变化较大的林地,土壤水分变异系数更大,所需的样点数也更多。     

时域反射仪的测量精度及其与中子仪的对比

野外和室内试验表明，用６０５０Ⅺ型时域反射仪（ＴＤＲ）测定土壤含水率与中子仪法相比，速度快，精度高；还发现随着导棒长度的增大，ＴＤＲ与烘干法测定结果的偏差有所增大，文中给出了５种导棒长度的校正公式     

样地林木生物量精度评定的研究

为了评定样地林木生物量的估算精度,利用方差--协方差传播律,导出平均断面积法、每木树高胸径法和径阶平均断面积法计算样地林木生物量的精度评定公式;应用实例,分析模型误差、树高误差和胸径误差对样地生物量的影响,并对3种计算样地林木生物量公式的精度进行比较.根据一尾叶桉林样地中90棵树木的分析结果,平均断面积法的精度为2.18%,每木法的精度为1.99%,径阶均值法的精度为1.89%.具体结论为:①样地林木生物量的精度可用公式进行评定;②每木法和径阶均值法计算的样地生物量精度较高,平均断面积法计算的样地生物量精度较低;③样地林木生物量的估算误差,主要受模型参数误差的影响,受树高和胸径误差的影响处次要地位.     

花生新品种郑农花15号丰产性、稳产性及品质性状分析

为了解花生新品种郑农花15号的优良特性,根据2015-2016年国家（北方片）花生区域试验产量结果,本研究利用高稳系数法和GGE双标图法对郑农花15号的丰产性和稳产性进行了评估,并根据品质化验结果对该品种的品质进行综合分析。结果表明：郑农花15号表现出较好的丰产性、稳产性和广泛的适应性,含有较高的蛋白含量和油酸含量,具有广阔的推广应用价值。     

手持GPS测量面积的精度分析

介绍了手持GPS在森林资源调查、工程造林中林地面积测量的精度,选择已知面积作为测量对象,对测量误差及其精度进行分析计算,结果表明:手持GPS测量林地面积的精度能够满足林业中的应用要求.     

水稻水分精确管理的知识模型研究

【目的】水稻是中国主要的粮食作物,其生长需消耗大量的水资源,因此水分精确管理对于水稻高效生产具有重要的意义。【方法】在分析和提炼水稻栽培理论与技术研究资料的基础上,通过定量描述水稻需水规律与栽培技术、品种类型、生态环境之间的动态关系,根据土壤水分平衡原理,采用土壤水势作为灌溉指标,建立水稻水分精确管理知识模型;基于系统工程思想,进一步在Microsoft Visual Studio.NET 2005平台上构建水分精确管理知识模型系统。【结果】模型具有灌溉管理方案设计以及动态调控的功能,在杭州和南京两个生态点进行的大田对比试验表明,两生态点按照模型设计方案进行水分管理的田块,其产量平均分别提高了6.9%和9.1%,灌溉水分生产率平均分别提高了53.61%和42.73%。【结论】该模型对于不同条件下的水稻水分精确管理具有较好的适用性和指导性。     

Educational Resources for Precision Agriculture

As site-specific management evolved into precision agriculture and began to be adopted by producers in the late 1980s and early 1990s, information about precision agriculture emerged in a variety of forms. Much of the information was initially available only in industry guides and popular press articles, such as Successful Farming and Farm Journal. Today, a variety of educational resources for both producers and advisors on precision agriculture has emerged, including books, proceedings of conferences, Extension bulletins, newsletters, industry guides, and multimedia modules. Recently, the Internet has had a significant influence on the production and dissemination of information on precision agriculture. The Internet has been a particularly valuable mode of information exchange due to the rapid evolution of technology and practices associated with precision agriculture, and because many of the early adopters of precision agriculture technologies were also early adopters of electronic communication technologies.     

A Data Generator for Evaluating Spatial Issues in Precision Agriculture

With the rapid rise in site-specific data collection, many research efforts have been directed towards finding optimal sampling and analysis procedures. However, the absence of widely available high quality precision agriculture data sets makes it difficult to compare results from separate experiments and to assess the optimality and applicability of procedures. To provide a tool for spatial data experimentation, we have developed a spatial data generator that allows users to produce data layers with given spatial properties and a response variable (e.g. crop yield) dependent upon user specified functions. Differences in response functions within fields can be simulated by assigning different models to regions in coordinate-(x and y) or feature space (multidimensional space of attributes that may have an influence on response). Noise, either unexplained variance or sensor error, can be added to all spatial layers. Sampling and interpolation error is modeled by sampling a continuous data layer and interpolating values at unsampled locations. The program has been successfully tested for up to 15000 grid points, 10 features and 5 models. As an illustration of the potential uses of generated data, the effect of sampling density and kriging interpolation on neural network prediction of crop yield was assessed. Yield prediction accuracy was highly related (correlation coefficient 0.98) to the accuracy of the interpolated layers indicating that unless data are sampled at very high densities relative to their geostatistical properties, one should not attempt to build highly accurate regression functions using interpolated data. By allowing users to generate large amounts of data with controlled complexity and features, the spatial data generator should facilitate the development of improved sampling and analysis procedures for spatial data.     

工业无线微机遥测系统误差原因及精度分析

为了使工业无线微机遥测系统获得的数据准确、可靠、系统误差必须在允许的范围内。工业无线微机遥测系统误差主要来自系统取样，编码和信道传送信号过程，详细分析了这三个环节产生误差的具体原因。     

陇春24小麦品种的丰产性和稳定性分析

[目的]为了全面了解陇春24小麦品种的丰产性能。[方法]依据2004～2005年甘肃省水地春小麦区域试验资料,运用联合方差分析法和高稳系数法(HSC),对陇春24和其他21个品种的丰产性和稳产性进行了分析,同时利用灰色关联度分析法对2004￣2005年小麦区域试验中相同地点的4个品种进行了综合评价。[结果]联合方差分析结果表明,2004年区域试验中,陇春24平均产量为8624.40 kg/hm2,较对照高原602增产6.65%;2005年区域试验平均产量为7 627.35 kg/hm2,较对照增产11.65%。HSC分析表明,陇春24、91043的高稳系数与产量间的相关系数为-0.8515,高稳系数与变异系数的相关系数为0.7845,高稳系数与标准差间的相关系数为0.4806。[结论]陇春24小麦品种丰产稳产性好,具有较大的增产潜力,在甘肃河西及沿黄灌区适应性较好。