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ZTE Communications 2008年第2期 15-19页

作者： Tian Hui, Tao Xiaofeng (beijing University of Posts and Telecommunications, beijing 100876, china)

Combining the performance advantages of both Wireless Local Area Network (WLAN) and Ad hoc network, Wireless Mesh Network (WMN) is characterized by large capacity, high rate and wide coverage. It has become an effective means for broadband wireless access and can be applied flexibly in various wireless environments. The wired connections between base stations in traditional cellular mobile communications systems can no longer satisfy the requirements for flexible deployment, low cost, high scalability and good reliability. The wireless Mesh architecture for IP-based base stations is thus introduced as an optional solution to support the flat and simplified next generation mobile communications networks. The key technologies used to support self-organization of IP-based base stations involve several aspects, including on-demand self-organization of base stations, joint radio resource scheduling mechanism, routing, security and network management.

关键词： Mesh Wireless Mesh Architecture for IP-Based Base Stations WMN IP

Zinc up-regulated the expression of the rice metallonthionein gene family and enhanced the zinc tolerance of yeast cells

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Progress in Natural Science:Materials International 2007年第10期17卷 1166-1171页

作者： Xu Yufeng, Zhou Gongke, Li Yiqin and Liu Jinyuan(Laboratory of Molecular Biology and Protein Science Laboratory of the Ministry of Education, Department of Biological Sciences and Biotechnology, Tsinghua University, beijing 100084, china) Laboratory of Molecular Biology and Protein Science Laboratory of the Ministry of Education Department of Biological Sciences and Biotechnology Tsinghua University Beijing 100084 China

Northern blot and functional complementation assay were employed to analyze the effects of zinc on expression of ten rice metallothionein genes (OsMT-Is) in rice seedlings and the growth of yeast cells transformed with OsMT-Is. Northern blot revealed that in shoots of the rice seedlings treated with different Zn2+concentrations, expression of most members of OsMT-I family was increased, except the type 4 OsMT-Is (OsMT-I-4a, 4b and 4c). In roots, Zn2+significantly increased the transcription of OsMT-I-1b and OsMT-I-2c, but reduced the trascription of OsMT-I-1a and OsMT-I-3.. When these ten cDNAs were heterologously expressed in zinc sensitive yeast mutant, all transgenic yeasts showed increased tolerance to Zn2+, and zinc accumulation in these yeast cells also increased. These indicated that OsMT-I family members might respond to extra Zn2+, and they could enhance Zn2+ tolerance of cells by direct binding Zn2+.

关键词： rice metallothionein induced expression Zn2+ tolerance.

EQUILIBRIUM ALGORITHMS WITH NONMONOTONE LINE SEARCH TECHNIQUE FOR SOLVING THE TRAFFIC ASSIGNMENT PROBLEMS

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Journal of Systems Science & Complexity 2005年第4期18卷 543-555页

作者： ZHAO Hui GAO Ziyou School of Traffic and Transportation Beijing Jiaotong University Beijing 100044 China.

This paper presents a unified bination algorithms （such as FrankWolfe problems. Global convergence results are framework of the nonmonotone convex comAlgorithm） for solving the traffic assignment established under mild conditions. The line search procedure used in our algorithm includes the nonmonotone Armijo rule, the non- monotone Goldstein rule and the nonmonotone Wolfe rule as special cases. So, the new algorithm can be viewed as a generalization of the regular convex combination algorithm.

关键词： Traffic convex combination algorithm nonmonotone line search global convergence.

三江源区生态型产业的发展与示范区建设思路(英文)

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山地学报 2006年第6期24卷 744-760页

作者：方创琳刘海燕中国科学院地理科学与资源研究所中国科学院地理科学与资源研究所北京100101 中国科学院研究生院北京100049

从三江源地区生态保护与区域建设的双重目标出发,分析了三江源地区经济发展与产业结构的基本特征。首先,分析了三江源自然保护区发展生态产业在我国西部生态型产业发展与生态环境建设中的战略影响、在青藏高原生态型产业发展与生态环境... 详细信息

从三江源地区生态保护与区域建设的双重目标出发,分析了三江源地区经济发展与产业结构的基本特征。首先,分析了三江源自然保护区发展生态产业在我国西部生态型产业发展与生态环境建设中的战略影响、在青藏高原生态型产业发展与生态环境建设中的战略影响及在青海省生态型产业发展与生态环境建设中的战略影响,阐明三江源地区发展生态型产业的重大意义;接着分析三江源地区经济社会的基本特征,发现三江源地区由于地处高原地区,气候高寒干燥,并将三江源地区经济发展水平和青海省及全国发展水平作比较,认为三江源地区的经济发展表现出脆弱独特的高寒降效特征。分析该地区经济结构,发现三江源地区经济结构表现出粗放落后的经济特性,产业结构过分单一,地区发展基本上是依靠农牧经济,由于过分的依赖畜牧业和采矿业等资源开发型产业,本地资源开发很大程度上只进行初步利用,资源的深加工和再利用程度低,各产业链单一、短小,前向产业、后向产业和侧向产业发展滞后,造成中下游产业不发育,产业发展呈现封闭性、源头性、粗放性的特征。再者,该地区发展畜牧业经济产生的效益远小于生态环境破坏所造成的生态经济效益,旅游经济发展中旅游设施和开发靠基本靠外来投资,实际上造成经济效益在地区经济贡献中流失的实际情况,经济发展表现出典型的投入漏出特性。另外,从三江源地区的人口承载统计数据发现,该地区长期处于人畜超载特性,人口超载和利益驱动加剧地区脆弱生态环境的恶化。针对当地实际情况,文章提出了三江源地区生态型产业发展的基本思路与重点。整体发展思路立足于生态地区生态保护,从保护与可持续发展的双重角度出发,针对三江源保护区的特殊性和生态-生产-生活承载力,尊重自然规律和科学发展观,分阶段、分层次(核心层、缓冲层、试验层、外未层)提出三江源自然保护区产业发展的总体定位、发展目标、保护重点与发展方向,进而提出与资源优化配置及生态环境建设相适应的生态型产业体系和产业结构培育方案,建设若干个不同类型的示范区,推进三江源自然保护区国民经济的生态化和经济社会活动的生态化。并对建设方案的实施过程进行动态监测评估,对实施效果进行滚动预警。把三江源自然保护区建设成为生态、生产、生活共同繁荣的自然保护区、国家级可持续发展实验区和国家循环经济示范区。提出产业结构调整中“三个转变”的整体思路。即引导产业结构由单一畜牧业向林牧业-加工业-旅游业的多元化生态产业结构转变,建立生态型产业体系;引导产业结构由投入楼出型向投入产出型转变,推行集约型经济增长方式;引导产业结构由生产-生活型向生态-生产-生活型转变,推进国民经济生态化。进而提出要立足生态资源优势,培育和延伸生态型产业链,选择优化现代草畜业、现代医药和生态旅游业为主的支柱产业,建立资源节约型、环境友好型和生态型产业结构体系。文章进一步深入,提出生态农林牧业、生态工业和生态旅游业的发展思路与重点;生态型城镇建设目标与重点;与生态型产业体系和生态城镇建设相适应的生态移民的重点与方向以及生态能源建设与发展方向。鉴于三江源地区面积广大,地域辽阔,保护与开发过程中首先必须选择典型地区先行试验示范,在积累示范区成果和成功经验的基础上再逐步向周围广大地区因地制宜地推广。为此,建议根据三江源自然保护区综合保护与建设方案,选择重点建设地区和适宜建设地区,立足这些重点地区的资源禀赋条件及组合状况,经济社会发展基础、宗教民俗风俗、发展潜力和前景等,有选择、有重点地规划若干个生态经济示范区、生态重建示范区、生态旅游示范区和生态型小城镇建设示范区,对这些示范区提出详细规划设计方案,指明示范区内容、示范方向、示范重点和示范技术,提出各示范区的建设规模和建设模式。立足当地优势,提出要重点建设生态林牧业(种植、养殖、水利等)、生态工业(清洁生产)、生态旅游、生态城镇和生态科研产业示范区5种类型。为保障三江源地区从保护和建设的双重角度推进三江源地区生态型产业体系建设步伐,还从政策保障、基础设施建设、项目保障、空间管制、经费支持保障、动态滚动评估与滚动监测预警等方面提出了对策建议。

关键词：三江源生态型产业生态旅游生态重建示范

Calibrating the HXMT collimators using diffuse illumination

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Science china(Physics,Mechanics & Astronomy) 2010年第S1期53卷 36-39页

作者： HAN Dong1,JIN YongJie1,WU Mei2 & ZHANG Zhi1 1 Department of Engineering Physics & Center for Astrophysics,Tsinghua University,beijing 100084,china 2 Key Laboratory of Particle Astrophysics,Institute of High Energy Physics,Chinese Academy of Sciences,beijing 100049,china 1. Department of Engineering Physics & Center for Astrophysics Tsinghua University Beijing 100084 China 2. Key Laboratory of Particle Astrophysics Institute of High Energy Physics Chinese Academy of Sciences Beijing 100049 China

We propose a new method to calibrate the HXMT collimators by measuring the optical point spread function(PSF) of the hard X-ray modulation telescope(HXMT).The light transmission of the collimator at different viewing angles with a camera and a diffuse backlight placed behind the collimator is *** method is much easier to accomplish than measuring the PSF with a parallel optical *** experimental results are very consistent with the *** PSF of the collimator of the high energy X-ray telescope on HXMT is found to be in good agreement with the design,with accuracy better than 1 arcmin.

关键词： HXMT collimator point spread function Monte Carlo simulation diffuse illumination

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基于计算机图形学的SAR图像几何畸变仿真

系统仿真学报 2009年第9期21卷 2503-2508,2512页

作者：张帆洪文中国科学院电子学研究所微波成像国家级重点实验室北京100080 中科院研究生院北京100039

分析了传统的SAR图像几何畸变仿真方法,对其重采样方法和几何模型进行修正使其能够适用于机载SAR图像几何畸变仿真。指出了传统仿真方法在计算效率和精度方面的不足,并提出了能够提高这两项指标的基于计算机图形学的SAR图像几何畸变仿... 详细信息

分析了传统的SAR图像几何畸变仿真方法,对其重采样方法和几何模型进行修正使其能够适用于机载SAR图像几何畸变仿真。指出了传统仿真方法在计算效率和精度方面的不足,并提出了能够提高这两项指标的基于计算机图形学的SAR图像几何畸变仿真方法。通过该方法在DEM数据阴影区计算、典型目标几何畸变仿真中的应用,证明了该方法能够高效地计算阴影遮挡和高精度地重采样。

关键词：合成孔径雷达(SAR) 图像仿真几何畸变计算机图形学

Influence of surfactants used in surfactant-polymer flooding on the stability of Gudong crude oil emulsion

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Petroleum Science 2010年第2期7卷 263-267页

作者： Dong Zhaoxia Lin Meiqin Wang Hao Li Mingyuan Enhanced Oil Recovery Research Center China University of Petroleum Beijing 102249 China

The influences of an anionic-nonionic composite surfactant and petroleum sulfonate, used in surfactant-polymer flooding in Shengli Gudong oilfield, East china, on the interfacial properties of Gudong crude model oil and synthetic formation water was studied by measuring interfacial tension, interfacial viscoelasticity and Zeta potential. The in？ uence of the surfactants on the stability of Gudong water-in-oil （W/O） and oil-in-water （O/W） emulsions was evaluated by separating water from the W/O emulsion and residual oil in the aqueous phase of the O/W emulsion respectively. The results showed that the two kinds of surfactants, namely anionic-nonionic composite surfactant and petroleum sulfonate, are both able to decrease the interfacial tension between the oil phase and the aqueous phase and increase the surface potential of the oil droplets dispersed in the O/W emulsion, which can enhance the stability of the W/O and O/W crude oil emulsions. Compared with petroleum sulfonate, the anionic-nonionic composite surfactant is more interfacially active and able to enhance the strength of the interfacial film between oil and water, hence enhance the stability of the W/O and O/W emulsions more effectively.

关键词： Surfactant Gudong crude oil interfacial properties emulsion stability

Quantum Topological Studies on the Molecular Complexes-CO_2-NCH and CO_2-OH_2

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Chemical Research in Chinese Universities 1993年第1期9卷 65-69页

作者： LI Qing-ming and FU Xiao-yuan (Department of Chemistry, beijing Normal University, beijing, 100875)ZHANG Jing-chang and CAO Wei-liang (beijing Institute of Chemical Technology, beijing, 10003.)

Topological properties of charge distribution for the title complexes and their constituent are analyzed by using ab initio calculations at 3.21G basis set. The results obtained are compared with those originated from ab initio and energy decomposition method. It has been determined that the title molecular complexes are T-shaped. The characteristics of the bonds and the changes originated from the formation of the complexes are discussed.

关键词： Charge density Molecular complex ab initio calculation

MKK7-Mediated Signaling Pathways in Arabidopsis

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MKK7-Mediated Signaling Pathways in Arabidopsis