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Search Results: 1 - 10 of 137996 matches for " 董志良DU Qinjun "
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基于逐次DEA的矿产资源开发效率评价
Evaluating Mineral Resources Exploitation Efficiency with Sequential Data Envelopment Analysis

都沁军,武建章,冯兰刚,
DU Qinjun
,WU Jianzhang,FENG Langang,DONG Zhiliang

- , 2015,
Abstract: 摘要 从劳动力投入、资本投入、土地等自然资源投入,经济效益产出、环境效益产出等方面来构建矿产资源开发评价指标体系。采用逐次数据包络分析(SDEA)方法来确定各级效率前沿面,实现对各决策单元的矿产资源开发效率的分级划分。 以河北省2011年各县区铁矿资源开发效率评价,实例验证了指标体系的可用性与SDEA方法的有效性
Mutation Effect of Plasma Immersion N+ Ion Implantation on Plumule Cells of M1 in Pea Seeds
等离子体浸没N+ 注入对豌豆胚芽细胞的诱变效应 Mutation Effect of Plasma Immersion N+ Ion Implantation on Plumule Cells of M1 in Pea Seeds

DU Lan-fang,GU Zhi-liang,ZHONG Hua,DONG Ying,WU Mei-ping,PAN Chong-guang,
杜兰芳
,,钟华,,吴美萍,潘重光

遗传 , 2000,
Abstract: Preliminary results indicated that the pea seeds after implantation with plasma immersion ion was not only restrained spindle form but also induced plumule cell nuclear and chromosomal aberration.Being an economical and available method plasma immersion ion implantation in mutagenic breeding is proposed.
Hydrology and Pollution Characteristics of Urban Runoff: Beijing as a Sample
城市降雨屋面、路面径流水文水质特征研究

DONG Xin,DU Peng-fei,LI Zhi-yi,YU Zheng-rong,WANG Rui,HUANG Jin-liang,
,杜鹏飞,,喻峥嵘,王锐,黄金

环境科学 , 2008,
Abstract: The purpose of this study is identification and characterization of hydrological process of urban runoff, as well as concentration variation of pollutants in it. Samples were collected in 4 rainfall events in Beijing from Jun. 2006 to Aug. 2006. Hydrology and pollution of the rainfall-runoff process were analyzed on roof and road. Study results show that the shapes of hydrological curves of runoff, despite for a 5min~20min delay and a milder tendency, are similar to rainfall curves. Runoff coefficients of roof are 0.80~0.98, while 0.87~0.97 of road. Event Mean Concentrations (EMC) of pollutants are influenced by build-up and wash-off features, which lead to a higher concentration in road runoff than in roof runoff. Major pollutants that excess the water quality standards are COD, TN, and TP. Evident correlations (>0.1) are found between pollutants. Correlation with particles are higher for COD and SO42- (>0.5), while lower for nutrients (<0.5). First Flush Effects (FFE) are found and affected by several factors; such as pollutant variety, types of land covers, and rainfall intensity. FFE are found more intense in SS, more frequently in road runoff, and more difficult to form for COD and nutrients with low rainfall intensity. Therefore, control of first period of runoff would be an effective approach for runoff management in Beijing.
军民科技创新资源信息平台建设路径与运行机制研究
,丁超
科技进步与对策 , 2011,
Abstract: 在探讨军民合作信息交流障碍,并提出信息交流平台建设目标和建设原则的基础上,提出了军民科技创新资源信息服务平台建设中的风险控制方案,同时提出平台的建设路径。军民合作创新资源信息服务平台风险控制建设路径运行机制
微通道人工空穴汽泡核化跃离的latticeBoltzmann模拟
,徐进
工程力学 , 2012,
Abstract: 研究微纳尺度的汽泡动力学行为是微纳流动与传热的基础前沿。基于作者提出的能描述相变之热质传递的latticeBoltzmann大密度比多相流复合模型,该文数值研究了单微通道中汽泡在人工空穴上核化跃离的物理过程,量化分析了汽泡核化、跃离和运动对微通道内液相流动和传热的影响,可为理论探索人工空穴强化微通道传热提供有意义的参考。
河北省互联网发展的地理特征分析
,白翠玲
地球信息科学学报 , 2007,
Abstract: 信息流在社会空间结构研究尤其是在城市和区域空间结构研究中,占据了越来越重要的地位,本文以网络的基础设施-网络带宽数据为基础,分析了信息流的等级结构和结构模式,揭示了目前河北省互联网网络结构的空间特征,并对其未来的发展提出初步的设想。
UBF-接触氧化处理船舶生活污水
,
长安大学学报(自然科学版) , 2005,
Abstract: 针对船舶生活污水的特点,对UBF接触氧化工艺处理船舶生活污水进行了实验研究,在UBF、接触氧化池、接触沉淀池的有效水力停留时间分别为1.5h、2.0h、1.0h时,出水BOD5、SS均小于50mg?L-1,并实现了污水、污泥的一体化处理;重点分析了UBF的结构特征及其基质降解的机理,其具有厌氧生物滤池的特征。并给出了适合船舶生活污水处理的装置构造形式及设计参数。
软土地区基坑工程深层水平位移报警值分析
胡珩,,罗彦
铁道工程学报 , 2011,
Abstract: ?研究目的:目前越来越多的基坑工程建设在软土地区,如何保证软土条件下的基坑开挖安全和经济性成为大家所关心的问题,而合理设置基坑监控报警值是降低基坑风险的有效方法。目前规范中所提出的监控报警值更多是在非软土条件下建立的,并不太适用于软土条件,因此有必要制定适用于软土地区的报警值标准。研究结论:通过对以往软土地区的基坑实测数据的统计分析,得出:(1)软土地区一级基坑深层水平位移最大值集中于60~100mm,且随着开挖深度的增加逐渐减少;(2)在不改变支护结构稳定的前提下,会明显增加支护桩的变形量,但不改变其变形规律;(3)支护桩最大水平位移量随土体弹性模量的增加基本呈线性减少。
偶极子在城区渗流场的结构物模拟中的应用
叶锋,曹洪,
岩土力学 , 2010,
Abstract: 城区渗流场中地下阻水结构物众多,由于结构物的角点为奇异点,而且结构物的尺寸跟整个城区渗流场的尺寸相比非常小,这导致现有的计算方法难以对城区渗流场进行模拟分析。针对城区渗流场的这些特点,通过引进流体力学的复势、偶极子等理论,采用抽注水井对结构物进行模拟。通过控制井流量的大小,以形成强弱程度不同的阻水效果,而单元尺寸可以以井点间距为尺度,用较少的节点和单元即可对地下结构物进行处理,达到简化计算的目的。抽注水井法是一种简化的模拟算法,它忽略了结构物附近局部区域流场失真的情况,强调在宏观上与真实流场接近。
一类陈–西蒙斯–薛定谔方程径向对称解的非存在性结论
The Nonexistence Results of Radial Solutions to Some Chern-Simons-Schr?dinger Equations
 [PDF]

, 张灿,, 谢俊, 朱康力, 万优艳
Pure Mathematics (PM) , 2014, DOI: 10.12677/PM.2014.45031
Abstract:
通过变分法研究得到:当参数λ大于零时,一类带正的径向对称的位势和特殊非线性项的陈–西蒙斯–薛定谔方程不存在非平凡的径向对称解。
Using variational methods, we obtain that the nonexistence of radial solutions to some Chern-Si- mons-Schr?dinger equations with radial symmetric potentials and special nonlinearities when the parameter λ is positive.
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