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End-to-end utility-based resource allocation for multi-RAT nodes in heterogeneous cognitive wireless networks

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The Journal of China Universities of Posts and Telecommunications 2013年第2期20卷 19-24页

作者： CHEN Feng XU Wen-jun LIN Jia-ru NIU kai ma hong-yu Key Laboratory of Universal Wireless Communications Ministry of Education Beijing University of Posts and Telecommunications

This paper studies the problem of effective resource allocation for multi-radio access technologies （Multi-RAT） nodes in heterogeneous cognitive wireless networks （HCWNs）. End-to-end utility, which is defined as the delay of end-to-end communication, is taken into account in this paper. In the scenario of HCWNs, it is assumed that the cognitive radio nodes have the ability of Multi-RAT and can communicate with each other through different paths simultaneously by splitting the arrival packets. In this paper, the problem is formulated as the optimization of split ratio and power allocation of the source cognitive radio node to minimize the delay of end-to-end communication, and a low complexity step-by-step iterative algorithm is proposed. Numerical results show good performance of the proposed algorithm over two other conventional algorithms.

关键词： resource allocation heterogeneous cognitive wireless networks end-to-end utility Multi-RAT

New Periodic Wave Solutions and Their Interaction for （2＋1）-dimensional KdV Equation

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Chinese Quarterly Journal of mathematics 2009年第4期24卷 525-536页

作者： GE Dong-jie ma hong-cai yu Yao-dong College of Science Donghua University Shanghai 201620 China

A class of new doubly periodic wave solutions for （2＋1）-dimensional KdV equation are obtained by introducing appropriate Jacobi elliptic functions and Weierstrass elliptic functions in the general solution（contains two arbitrary functions） got by means of multilinear variable separation approach for （2＋1）-dimensional KdV equation. Limiting cases are considered and some localized excitations are derived, such as dromion, multidromions, dromion-antidromion, multidromions-antidromions, and so on. Some solutions of the dromion-antidromion and multidromions-antidromions are periodic in one direction but localized in the other direction. The interaction properties of these solutions, which are numerically studied, reveal that some of them are nonelastic and some are completely elastic. Furthermore, these results are visualized.

关键词： (2+1)-dimensional KdV equation multilinear variable separation approach elliptic functions periodic wave solutions localized excitations interaction property nonelastic completely elastic

management with the insufficient proximal landing zone for endovascular repair in aortic dissection

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Chinese Medical Journal 2011年第19期124卷 3003-3007页

作者： ma Hao YANG hong-yu ZOU Jun-jie ZHANG Xi-wei Department of General Surgery the First Affiliated HospitalNanjing Medical University Department of General Surgery Jiangsu Province Hospital Nanjing Jiangsu 210029 China

Background Sufficient length of the proximal landing zone （PLZ） is the key for a successful thoracic endovascular aortic repair （TEVAR） of an aortic lesion. The aim of this research was to investigate the safety, feasibility, efficacy, and problems of endovascular repair for aortic dissection with insufficient *** The clinical data between August 2005 and February 2010 from patients with insufficient PLZ for endovascular repair of aortic dissection were retrospectively reviewed. According to the classification proposed by Ishimaru, aortic zone 0 was involved in 3 cases, zone 1 in 10 cases, and zone 2 in 11 cases. A hybrid surgical procedure of supraortic debranching and revascularization, directly coverage the orifice of left subclavian artery, or a left common carotid artery chimney graft technique were performed to obtain an adequate proximal aortic landing *** There was no significant difference in risk factors and diameter of the PLZ between Zone 0, Zone 1, and Zone 2. But the length of the PLZ was significantly different in the three groups （P 〈0.01）. There was no significant difference in technical and clinical success rate between the *** The procedure for extending an insufficient PLZ for endovascular repair for aortic arch pathology is feasible and relatively safe. The applicability of TEVAR in such aortic disorders may be expanded.

关键词： endovascular procedures aortic dissection proximal landing zone aorta, thoracic

Measurement System of Uniformity between Breech Horizontal Platform and Datum Tube Axis of Rocket Artillery

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Semiconductor Photonics and Technology 2007年第3期13卷 235-237页

作者： GUO Rui ma hong YAN yu-feng BAI Su-ping Changchun University of Science and Technology Changchun 130022 CHN

The purpose of this development is to detect the parallelism between the breech horizontal platform and the datum tube axis of the rocket artillery. The located aiming mechanism at the muzzle and located adjustment mechanism at the breech are designed in the system. Besides those, the system also uses an autocollimator with accuracy of 1″ and a collimating mirror together to determine the axis of the datum tube. An electronic level with accuracy of 2″ is employed to measure and display the value of the included angle and the parameter of the inclined direction. The entire accuracy of this system is σ≤±9.1″. This paper describes the composition and the operating principle of the system and analyzes the accuracy. The development of this system supplies reliable measurement method for new rocket artilleries and artilleries, and this technology is of a good application prospect.

关键词： rocket artillery autocollimator electronic level instrument uniformity

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基于科赫曲线分形结构太赫兹带通滤波器

光谱学与光谱分析 2020年第3期40卷 733-737页

作者：马宏宇李九生中国计量大学太赫兹研究所

太赫兹滤波器是太赫兹通信、太赫兹成像和太赫兹检测等太赫兹应用系统中不可或缺的功能器件。按照不同的分类方式,滤波器有不同的种类,常见的按照选频功能可分为高通滤波器、低通滤波器、带阻滤波器和带通滤波器。为了实现在太赫兹波段... 详细信息

太赫兹滤波器是太赫兹通信、太赫兹成像和太赫兹检测等太赫兹应用系统中不可或缺的功能器件。按照不同的分类方式,滤波器有不同的种类,常见的按照选频功能可分为高通滤波器、低通滤波器、带阻滤波器和带通滤波器。为了实现在太赫兹波段的滤波效果,世界各地的研究人员利用不同的结构、材料和控制方式实现了功能各异的太赫兹滤波器,但是考虑到设计的器件要应用到太赫兹系统中,成本低廉、结构简单、性能优越的太赫兹滤波器一直是研究人员的追求。分形概念自提出以来在很多研究领域都有了快速发展,但是在太赫兹波段的应用还不是很常见,特别是应用于太赫兹功能器件的设计。引入分形中科赫曲线的概念设计并制备了一种新型的太赫兹带通滤波器,该滤波器是在金属薄膜上刻蚀出科赫曲线分形结构,当太赫兹波垂直入射到该滤波器时候实现了在太赫兹波段的窄带滤波。在滤波器的设计过程中,追求理论与实验相结合,首先在电磁仿真软件中建立科赫曲线分形结构滤波器模型进行计算,探究分形结构应用于太赫兹波段进行滤波的可行性,在进行多次计算之后得到优化后的尺寸和结构,然后根据优化后的尺寸加工出科赫曲线分形结构太赫兹滤波器样品,并且将样品放在太赫兹时域光谱系统中进行实验测量,得到实验数据后与仿真结果进行比较。在仿真中利用了时域有限差分法模拟科赫曲线分形结构太赫兹带通滤波器的传输特性,优化后的仿真结果表明:滤波器的谐振频率为0.715 THz,透射系数能够达到0.92,-3 dB带宽为21.9 GHz,将仿真得到的散射参数进行S参数反演得到了太赫兹滤波器样品的电磁参数,这在理论上分析了太赫兹波在谐振点处产生透射增强的原因。利用飞秒激光微加工系统制备了尺寸优化后的科赫曲线分形结构太赫兹带通滤波器样品,然后使用太赫兹时域光谱系统对样品的传输特性进行测试,对实验得到的时域数据进行快速傅里叶变换之后得到频域数据,再把频域数据进行归一化处理后与之前的电磁仿真结果进行对比,发现实验测得的结果与电磁软件仿真得到的结果较为吻合。

关键词：太赫兹带通滤波器科赫曲线分形参数反演太赫兹时域光谱

Enhanced expressions and activations of leukotriene C4synthesis enzymes in D-galactosamine/lipopolysaccharide-induced rat fulminant hepatic failure model

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World Journal of Gastroenterology 2008年第17期14卷 2748-2756页

作者： Kui-Fen ma hong-yu Yang Zhe Chen Luo-Yang Qi Dan-Yan Zhu Yi-Jia Lou Institute of Pharmacology & Toxicology andBiochemical Pharmaceutics College of Pharmaceutical SciencesZlaejiang University Hangzhou 310058 Zhejiang Province China

AIM： To investigate the expression and activity of leukotriene C4 （LTC4） synthesis enzymes and their underlying relationship with cysteinyl leukotriene （cys-LT） generation in a rat fulminant hepatic failure （FHF） model induced by D-galactosamine/lipopolysaccharide （D-GaIN/ LPS）. METHODS： Rats were treated with D-GaIN （300 mg/kg） plus LPS （0.1 mg/kg） for 1, 3, 6, and 12 h. Enzyme immunoassay was used to determine the hepatic cys-LT content. Reverse transcription-polymerase chain reaction （RT-PCR）, Western blot or immunohistochemical assay were employed to assess the expression or location of LTC4 synthesis enzymes, which belong to membrane associated proteins in eicosanoid and glutathione （maPEG） metabolism superfamily. Activity of LTC4 synthesis enzymes was evaluated by determination of the products of LTA4 after incubation with liver microsomes using high performance liquid chromatography （HPLC）. RESULTS： Livers were injured after treatment with D-GaIN/LPS, accompanied by cys-LT accumulation at the prophase of liver injury. Both LTC4 synthase （LTC4S） and microsomal glutathione-S-transferase （mGST） 2 were expressed in the rat liver, while the latter was specifically located in hepatocytes. Their mRNA and protein expressions were up-regulated at an earlier phase after treatment with D-GaIN/LPS. Meantime, a higher activity of LTC4 synthesis enzymes was detected, although theactivity of LTC4S played the main role in this case. CONCLUSION： The expression and activity of both LTC4S and mGST2 are up regulated in a rat FHF model, which are, at least, partly responsible for cys-LT hepatic accumulation.

关键词： Cysteinyl leukotriene Micmsomal glutathioneS-transferase 2 Leukotriene C4 synthase D-galacto-samine/lipopolysaccharide Fulminant hepatic failure

村镇建筑带限位装置摩擦隔震体系的参数影响研究

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振动与冲击 2011年第11期30卷 148-152页

作者：赵桂峰马玉宏广州大学土木工程学院广州510006 广州大学工程抗震研究中心广州大学减震控制与结构安全重点实验室广州510405

针对村镇建筑带限位装置摩擦隔震技术,建立了隔震装置的综合恢复力模型和隔震体系的运动方程,编制了考虑摩擦效应的非线性分析程序,详细分析了隔震层摩擦系数、限位装置弹性刚度和屈服位移等因素对隔震体系的影响,最终通过大量计算给出... 详细信息

针对村镇建筑带限位装置摩擦隔震技术,建立了隔震装置的综合恢复力模型和隔震体系的运动方程,编制了考虑摩擦效应的非线性分析程序,详细分析了隔震层摩擦系数、限位装置弹性刚度和屈服位移等因素对隔震体系的影响,最终通过大量计算给出了参数选取的合理取值范围,可为该隔震体系的简化设计和实际应用提供依据。

关键词：村镇建筑限位装置摩擦基础隔震

全甲基及其多胺修饰环糊精与牛血清白蛋白的相互作用

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高等学校化学学报 2007年第3期28卷 458-461页

作者：康澍陈湧史珺马玉红刘育南开大学化学系元素有机化学国家重点实验室天津300071

制备了两个多胺修饰全甲基化环糊精,即单-[6-(乙二胺)-6-脱氧]-七-(2,3,6-三甲氧基)-β-环糊精(4)和单-[6-(二乙烯三胺)-6-脱氧]-七-(2,3,6-三甲氧基)-β-环糊精(5),并采用荧光和紫外-可见光谱方法测定了全甲基化环糊精及其多胺修饰衍... 详细信息

制备了两个多胺修饰全甲基化环糊精,即单-[6-(乙二胺)-6-脱氧]-七-(2,3,6-三甲氧基)-β-环糊精(4)和单-[6-(二乙烯三胺)-6-脱氧]-七-(2,3,6-三甲氧基)-β-环糊精(5),并采用荧光和紫外-可见光谱方法测定了全甲基化环糊精及其多胺修饰衍生物在磷酸缓冲溶液中(25℃,pH=7.2)与牛血清白蛋白形成化学计量比为8∶1的超分子配合物的稳定常数.结果表明,全甲基化环糊精对牛血清白蛋白具有强于天然环糊精和部分甲基化环糊精的分子键合能力,而经过多胺修饰的全甲基化环糊精衍生物则显示了更强的键合能力,这些强的键合能力源于疏水作用、静电作用和氢键作用的协同效应.

关键词：全甲基化环糊精衍生物光谱滴定牛血清白蛋白超分子化学

采用Zeeman效应与饱和吸收法的激光器稳频

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光电工程 2006年第3期33卷 123-126页

作者：马红玉徐震王育竹中国科学院上海光学精密机械研究所量子光学实验室中国科学院研究生院北京100039

由于塞曼效应中性原子的超精细能级在磁场中会产生塞曼分裂,且对于左旋和右旋圆偏振光原子能级的偏移不同,因此利用Zeeman效应的这种特性与饱和吸收相结合的方法对光栅外腔反馈的半导体激光器系统进行稳频。这种方法能够将激光频率稳定... 详细信息

由于塞曼效应中性原子的超精细能级在磁场中会产生塞曼分裂,且对于左旋和右旋圆偏振光原子能级的偏移不同,因此利用Zeeman效应的这种特性与饱和吸收相结合的方法对光栅外腔反馈的半导体激光器系统进行稳频。这种方法能够将激光频率稳定地锁在原子吸收谱线的峰值处,锁频后激光器不易失锁,用于激光冷却铷原子实验。

关键词： Zeeman效应饱和吸收光谱稳频