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用年费用最小法计算管路经济管径

水电能源科学 2011年第8期29卷 118-120页

作者：肖璐赵廷红张春杨柯宋永占兰州理工大学能源与动力工程学院甘肃兰州730050

针对管路直径对造价最大影响的问题,以景泰川提水工程为例,综合考虑管道与水泵的关系,以年费用最小为目标确定管路经济管径,将求解经济管径的工程问题转化为求解年费用最低的经济问题。计算结果表明,该方法简便、精度较高,可为已建管路... 详细信息

针对管路直径对造价最大影响的问题,以景泰川提水工程为例,综合考虑管道与水泵的关系,以年费用最小为目标确定管路经济管径,将求解经济管径的工程问题转化为求解年费用最低的经济问题。计算结果表明,该方法简便、精度较高,可为已建管路的节能改造提供参考。

关键词：管路年费用最小值经济管径水泵型号泵站效率有机整体

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边不对称网络的QoS组播路由算法

天津大学学报（自然科学与工程技术版） 2003年第2期36卷 160-164页

作者：王燕琳孙雨耕俎云霄天津大学电气与自动化工程学院天津300072 清华大学电机工程系北京100084

针对QoS组播路由问题,建立链路负载不对称网络模型,以平衡网络负载为目标提出一种基于带宽和延时约束的QoS组播路由遗传算法(BDMGA).通过对该算法的收敛性分析和与其他算法的性能比较研究表明,该算法构建的组播树费用较低,且算法具有很... 详细信息

针对QoS组播路由问题,建立链路负载不对称网络模型,以平衡网络负载为目标提出一种基于带宽和延时约束的QoS组播路由遗传算法(BDMGA).通过对该算法的收敛性分析和与其他算法的性能比较研究表明,该算法构建的组播树费用较低,且算法具有很强的均衡负载能力,可有效避免链路拥塞,提高网络运行性能.此外,在小规模的网络上能够以较快的速度收敛到全局最优解.

关键词：组播路由服务质量遗传算法负载平衡

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浅谈英语中的后置定语

陕西广播电视大学学报 2001年第4期3卷 85-88页

作者：马小强兰州大学外国语学院甘肃兰州730000

一般认为定语是英语句子的一个基本成分。英语中的定语的表达是灵活多样的 ,有些定语可以置于被修饰词的前面 ,有些则要跟在后面。本文论述了英语中后置定语的一些类型和特点。

关键词：英语学习后置定语例题分析语言表达语句结构

Preparation of micro-patterned surfaces of Si-N-O films and their influence on adhesion behavior of endothelial cells

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Science china(Technological sciences) 2010年第1期53卷 257-263页

作者： ZHENG Nan,YANG Ping,WANG QiYi,YANG ZhongHai & HUANG Nan Key Laboratory of Advanced technology for Materials of Education Ministry,Key Laboratory of Artificial Organ Surface Engineering of Sichuan,school of Materials Science and Engineering,Southwest Jiaotong {2.,Chengdu 610031,china 1. Key Laboratory of Advanced technology for Materials of Education Ministry Key Laboratory of Artificial Organ Surface Engineering of Sichuan School of Materials Science and Engineering Southwest Jiaotong University Chengdu 610031 China

Microgrooves were prepared on Si(100) surface by photolithography and wet ***,Si-N-O films were deposited on the microgrooves by unbalanced magnetron sputtering(UBMS) and micro-patterned surfaces of Si-N-O films were *** size of the micropatterns was measured by surface *** chemical composition of Si-N-O films were characterized by X-ray photoelectron spectrometry(XPS) and the wettability of the micropatterned surfaces was evaluated by contact angle *** behavior of endothelial cells adhered on the micro-patterned surfaces,including cells adhesion,proliferation and orientation,was evaluated by cell culture test and Alamar blue *** results showed that the amount and activity of endothelial cells on micro-patterned samples were higher than those on flat *** one day's incubation,the cells were well guided along the *** days later,most of the cells grew across the grooves and contacted each *** activity was also much higher than that on flat *** was suggested that the adhesion and proliferation of endothelial cells could be effectively enhanced by micropattern method.

关键词： micropatterns Si-N-O film endothelial cell unbalanced magnetron sputtering

RESEARCH ON HYDRODYNAMIC AND WATER QUALITY MODEL FOR TIDAL RIVER NETWORKS

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Journal of Hydrodynamics 2003年第2期15卷 64-70页

作者： Xu Zu xin, Lu Shi qiang school of Environment Science and Engineering, State Key Laboratory of Pollution Control and Resource Reuse, Tongji university, Shanghai 2.0092.{2. school of Environment Science and Engineering State Key Laboratory of Pollution Control and Resource Reuse Tongji University Shanghai 200092 China

Hydrodynamic and water quality model for tidal river network is set up withMIKE11 modeling system, according to the features of tidal river networks in plain area. The modelwas calibrated using the hydrological and water quality data of 1999, and the results show that thesimulated values agree with the measured data very well. This model is used to numerically analyzethe effects of low flow augmentation on hydrodynamic and water quality conditions of Suzhou *** simulation results show that the flow augmentation can increase net discharge of Suzhou Creekand improve its ability of re-aeration; and its concentration of dissolved oxygen in the rivernetworks can also increase correspondingly.

关键词： tidal river network water quality model suzhou creek low flow augmentation

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藏族大学生的民族认同

心理学报 2004年第1期36卷 83-88页

作者：万明钢王亚鹏西北师范大学心理系兰州730070 北京师范大学心理学院北京100875

个体从自己的母体文化进入陌生的异文化后 ,一方面面临着民族认同的困境 ,另一方面面临着文化适应的考验 ,同时还面临着心理疏离感的困扰。本研究以 2.85名藏族大学生为被试 ,研究了藏族大学生的民族认同。研究结果表明 :(1)藏族大学生... 详细信息

个体从自己的母体文化进入陌生的异文化后 ,一方面面临着民族认同的困境 ,另一方面面临着文化适应的考验 ,同时还面临着心理疏离感的困扰。本研究以 2.85名藏族大学生为被试 ,研究了藏族大学生的民族认同。研究结果表明 :(1)藏族大学生的民族认同主要包括消极的民族认同、积极的民族认同和主流文化认同等三方面。民族认同的不同方面其影响因素互有差异 ,但总体而言 ,汉族朋友的数量、父母的民族身份、学习汉语的时间以及汉族的接受性等可以预测藏族大学生的民族认同。 (2.)民族认同的不同成分与不同的文化适应策略之间存在着广泛的正相关或负相关。 (3)消极的民族认同与失范感、社会孤立感和文化分离感之间存在着显著的正相关 ,而同自我分离感之间相关并不显著 ;而主流文化认同和积极的民族认同与失范感、社会孤立感、文化分离感、自我分离感之间的相关都不显著。

关键词：藏族大学生文化适应民族认同心理疏离感

Nonheme Oxovanadium(V,IV) Complexes Catalyze the Oxidative Cleavage of Catechols

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Chinese Chemical Letters 1997年第6期8卷 547-550页

作者： Bo Yan ZHANG Yi ZHANG Bao Wei CHEN Kui WANG (Inorganic Chemistry Department. school of Pharmaceutical sciences. Beijing Medical {2., Beijing 100083) BEIJING MED UNIV SCH PHARMACEUT SCIDEPT INORGAN CHEMBEIJING 100083PEOPLES R CHINA

It was found that the oxovanadium(V) complex of triethanolamine (TEA) exhibits catalytic activity to the oxidative cleavage of catechols. On the other hand. the vanadyl nitrilotriacetic acid (NTA) complex is inactive. but leads to the formation of stable ternary complex. The main products of the catalytic oxidative cleavage of 3.5-di-tert-butylcatechol were separated and characterized. Based on the results. a reaction mechanism was discussed

关键词： ppm TEA FAB Complexes Catalyze the Oxidative Cleavage of Catechols Nonheme Oxovanadium

SMALLEST g-SUPERSOLUTION FOR BSDE WITH CONTINUOUS DRIFT COEFFICIENTS

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Chinese Annals of Mathematics,Series B 2000年第3期21卷 359-366页

作者： LIN QINGQUAN (school of Mathematics and System Science, Shandong university, Jinan 2.0100,{2..) PENG SHIGE(school of Mathematics and System Science, Shandong university, Jinan 2.0100,{2..) E-mail: Linqingquan@math. sdu. cn Peng@sdu. edu. cn school of Mathematics and System Science Shandong University Jinan 250100 China

The authors prove the existence and uniqueness of smallest g-supersolution with an equality constrains on (y, z) for one demensional stochastic differential equations whose drift coefficients are continuous and linear... 详细信息

关键词： Backward stochastic differentail equation g-supersolution Constraint

General fuzzy number intuitionistic fuzzy arithmetic aggregation operators based on fuzzy structured element

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General fuzzy number intuitionistic fuzzy arithmetic aggrega...