非平衡系统的自组织与农业

耗散结构理论对当代科学和哲学的影响日益显著。本文运用其中的非平衡系统的自组织理论,结合农业系统中的一些问题进行了讨论。     

库尔勒香梨花序、序位和气温对座果率的影响

通过对库尔勒香梨（简称香梨）不同序数、同一花序不同序位以及花期气温对座果率影响的调查分析，发现香梨的同一花序随着序位的升高座果率逐渐下降。在对香梨疏花时，初果期的幼树留取花序基部1，2，3序位的花朵，结果盛期的成年树序数少的花序保留基部1，2，3序位的花朵，序数多的留取基部1～4序位或1～5序位的花朵为最佳留花位置。     

积分算子与高阶偏微分方程组

In this paper, by using integral operator mathod, we investigate a class of higher order partial differential equations with multiple Laplace operator in higher dimensions. We have obtained the integral representation of solutions of this equation.     

矿业发展的可持续性评价

根据可持续发展的内涵，结合矿业发展的特点和规律，建立了一套在“发展程度”、“发展效率”、“发展潜力”和“发展协调度”这4个准则下设涵盖经济、技术、资源与环境4大系统的34个具体指标组成的综合反映矿业发展态势的矿业可持续发展评价的指标体系。并相应建立了评价指标、准则和目标的模糊三级递阶综合评价模型，运用本模型对我国有色金属矿业发展的可持续性评价进行了实证研究。     

Interpreting Soil Electrical Conductivity and Terrain Attribute Variability with Soil Surveys

Utilizing soil electrical conductivity (EC) measurements and terrain attributes for precision management will require secondary soil information for adequate interpretation. The objective of this study was to determine whether readily available second-order soil surveys were of adequate quality to aid with interpreting soil EC and terrain data. For three locations in Kentucky, USA, first-order soil surveys were created, second-order surveys reports were obtained, elevation was measured and used to calculate terrain attributes (slope, aspect, plan curvature, profile curvature), and bulk soil electrical conductivity was measured. Three analytical methods (an ordinary least squares analysis and two random field analyses), visual map assessment, and examination of least-squares means were used to assess the relationships between soil EC measurements, terrain attributes and first- and second-order soil surveys. The OLS and random field analyses were problematic. However, the ranking of the OLS F-statistics appeared to reflect the general relationship between landscape variables and first-order soil surveys. The landscape variables related particularly well with soil properties that had been impacted by past soil erosion. Unfortunately, however, second-order soil surveys in this study were not created at suitable scales to adequately interpret EC and terrain data regarding erosion history or other attributes. While these surveys may provide some useful information, field measurements, sampling, and observations will likely be required to develop high quality interpretations of soil EC and terrain attribute data.     

一类二阶微分方程的正同宿轨

运用变分方法证明了一类二阶微分方程ü-α(x)u+β(x)u2+γ(x)u3=0,x∈R的正同宿轨存在性,其中系数函数α(x),β(x),γ(x)满足xα'(x)≥0,xβ'(x)≤0,xγ'(x)≤0对任意x∈R成立.     

变型拖拉机转向梯形机构参数最佳值的确定

为了解决变型拖拉机转向性能差等问题，采取建立转向车轮实际转向角的数学模型，计算机辅助分析方法，可以确定转向梯形机构参数的最佳值，从而较好地解决了转向性能差等问题．     

衍生金融工具及其在企业财务管理中的作用

衍生金融工具是在汇率、利率、股票、债券和商品等交易工具的基础上衍生出来的，是金融创新的产物，有其自身的特点。该文阐述了衍生金融工具在国际金融市场上的产生背景、发展历史及在我国的发展状况，并对一些常见衍生金融工具进行了简要介绍。通过分析衍生金融工具的若干共性，指出其在企业融资、投资方面所能发挥的作用。     

用分段放缩法证明不等式

本文提出1种新的证明不等式的方法－分段放缩法。先将不等式转化成函数不等式，然后在每个局部区间上证明不等式。     

一类高阶非线性泛函微分方程的强迫振动性

给出了一类非线性泛函微分方程的新的强迫振动条件，推广了文献中的一些结果，同时还给出了一类非线性强迫中立型方程的振动条件．