加权污染负荷法筛选沈阳市重点工业污染源探讨

在重点污染源筛选时,从污染物排放量、污染物危害程度、污染源位置等方面综合考虑,用加权处理后的污染负荷一个指标来评价污染源的危害能力,通过排序确定环境管理应优先控制的污染源名单。     

污水土地处理技术发展及应用

污水土地处理技术是一种在土壤—微生物—植物系统共同作用下,而实现污水无害化的技术。本文归纳了国内外一些先进的土地处理污水技术及应用,并对其特点进行了探讨和分析。     

提高数字电子技术实验教学质量的分析

 数字电子技术是一门实践性较强的课程,提高实验教学质量是培养工科人才的重要保障,以调查问卷结果为基础,从学生的能动性、实验内容及硬件环境、教师的指导等3个方面,提出了提高数字电子技术实验课程教学质量的几点思考.     

蓝宝石的改善工艺

对蓝宝石进行高温扩散处理,通过加入不同的辅助剂,改善蓝宝石的颜色和透明度。实验证明加入辅助剂Al2O3、硼砂、Na2CO3、MgSO4.7H2O后,加热到1 500℃恒温环境,蓝宝石的透明度和颜色都能得到一定程度的改善;另外山东蓝宝石在热处理时加入柠檬酸,有利于反应的进行;结合X射线荧光光谱仪、紫外-可见光吸收光谱和红外光谱对蓝宝石的改善前后样品进行了对比测试,分析了改善后颜色和透明度变化的原因。     

基于组确认机制的车联网中最佳中继节点的选择

针对特定位置的车辆用户节点和Sink节点,通过选取最佳中继节点来最大限度提高车联网的端到端吞吐量.将上述问题纳入基于组确认机制的车联网模型中,结合数据重传技术及多跳中继技术,提出了最佳中继节点的选择算法OTNS.并借助非线性优化方法来求解,最终确定出车辆用户节点与Sink节点之间的最佳中继的位置,以使得该车辆用户节点与Sink节点间的端到端吞吐量达到最大值.最后通过仿真实验验证了OTNS算法的有效性,结果表明,最佳中继节点的选择方案有利于车联网性能的提高,相比于不使用中继节点,该方案使车联网端到端吞吐量的期望值得到了提高.     

基于逐次神经网络近似技术的轿车简化模型多学科设计优化

提出一种空间形变技术与神经网络近似技术及多学科可行性方法相结合的多学科设计优化方法,基于此方法对轿车简化模型进行多学科设计优化。该方法使用逐次递归近似技术与空间缩放技术,使得收敛空间逐步减小,近似精度逐步提高,利用此高精度的数学代理模型替代整车碰撞学科与NVH学科的有限元模型,最后,基于此代理模型进行车身多学科设计优化,使整车耐撞性得到提高,改善了车身的一阶振动特性,减轻了整车质量。     

基于非单调线性搜索技术的修正HS共轭梯度法

基于拟牛顿法中MBFGS修正技术,对HS共轭梯度法中搜索方向的计算公式进行了修正,在较弱的条件下,结合非单调Armijo线性搜索技术,证明了所提出的修正HS共轭梯度法具有全局收敛性,最后通过数值实验验证了所提出的算法的有效性。     

前腿横踢技术在跆拳道比赛中运用情况的调查分析

采用文献资料法、录象统计法、数理统计分析法对辽宁省2011年青少年跆拳道锦标赛中前腿横踢技术的使用情况进行统计分析．得出结论：辽宁省青少年运动员在跆拳道比赛中得分动作基本上以横踢类为主导;运动员在使用前腿横踢技术的时候击打力度不够;比赛中运动员使用前横踢及其衍生系列技术进攻得分率较高,单一的前腿横踢击打得分区域主要集中在躯干部位,击打头部得分很少．     

Estimation of wind erosion rates by using 137Cs tracing technique: A case study in Tariat-Xilin Gol transect, Mongolian Plateau

Wind erosion is one of the major environmental problems in semi-arid and arid regions. Here we established the Tariat-Xilin Gol transect from northwest to southeast across the Mongolian Plateau, and selected seven sampling sites along the transect. We then estimated the soil wind erosion rates by using the 137Cs tracing technique and examined their spatial dynamics. Our results showed that the 137Cs inventories of sampling sites ranged from 265.63=44.91 to 1279.54=166.53 Bq. m-2, and the wind erosion rates varied from 64.58 to 419.63 t. km-2. a-~ accordingly. In the Mongolia section of the transect （from Tariat to Sainshand）, the wind erosion rate increased gradually with vegetation type and climatic regimes; the wind erosion process was controlled by physical factors such as annual precipitation and vegetation coverage, etc., and the impact of human activities was negligible. While in the China section of the transect （Inner Mongolia）, the wind erosion rates of Xilin Hot and Zhengxiangbai Banner were thrice as much as those of Bayannur of Mongolia, although these three sites were all dominated by typical steppe. Besides the physical factors, higher population density and livestock carrying level should be responsible for the higher wind erosion rates in these two regions of Inner Mongolia.     

Using 137Cs tracing technique to estimate wind erosion rates in the typical steppe region,northern Mongolian Plateau

Wind erosion is one of the major factors of land degradation in the typical steppe region, northern Mongolian Plateau. Using ^137Cs tracing technique, we estimated the wind erosion rates of different pastures and abandoned farmland at Bayannur and Karakorum in Mongolia. The pastures and cutting grassland at Bayannur were slightly eroded by wind, with the rates of 64.58-169.07 t·km^-2.a^-1. The abandoned farmland in Karakorum, however, was strongly eroded by wind, with annual surface soil loss of 4.05 mm. a^-1, and wind erosion rates up to 6723.06 t· km^-2. a^-1. The total loss of surface soil due to wind erosion has been 17.4 cm since the cultivation of the steppe land in the 1960s. The wind ero- sion rate at the abandoned farmland was much higher than that at the typical steppe sites, showing that the cultivation led to serious wind erosion in the typical steppe region, northern Mongolian Plateau. By contrast, traditional livestock grazing resulted in less disturbance to the surface soil, and did not induce to devastating wind erosion, which plays an important role in maintaining the stability of the steppe ecosystem in the northern Mongolian Plateau.