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Subcarrier and power allocation algorithm based on inter-cell interference mitigation for OFDMA system

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The Journal of China Universities of Posts and Telecommunications 2007年第1期14卷 90-95页

作者： zou Ting DENG gang WANG Ying ZHANG Ping Wireless Technology Innovation Institute Beijing University of Posts and Telecommunications. Beijing 100876 China

This article proposes a dynamic subcarrier and power allocation algorithm for multicell orthogonal frequency division multiple access （OFDMA） downlink system, based on inter-cell interference （ICI） mitigation. Different from other ICI mitigation schemes, which pay little attention to power allocation in the system, the proposed algorithm assigns channels to each user, based on proportional-fair （PF） scheduling and ICI coordination, whereas allocating power is based on link gain distribution and the loading bit based on adaptive modulation and coding （AMC） in base transceiver station （BTS）. Simulation results show that the algorithm yields better performance for data services under fast fading.

关键词： ICI mitigation OFDMA cell edge user equipments(CEUs) cell centre user equipments (CCUs) dynamic resource allocation

Highly efficient nickel/phosphine catalyzed cross-couplings of diarylborinic acids with aryl tosylates and sulfamates

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Science China Chemistry 2014年第8期57卷 1126-1131页

作者： KE HaiHua CHEN XiaoFeng FENG YuanYuan zou gang Department of Fine Chemicals East China University of Science and Technology

Highly efficient cross-couplings of diarylborinic acids with aryl tosylates and sulfamates are reported for construction of biaryls using a tri(4-methoxyphenyl)phosphine-supported nickel catalyst system: Ni[P(4-MeOC6H4)3]2Cl2/2P(4-MeOC6H4)3 in the presence of K3PO4·3H2O in toluene. A variety of unsymmetrical biaryls could be obtained in good to excellent yields with1.5–3 mol% or 3–5 mol% catalyst loadings for aryl sulfamates and tosylates, respectively. In sharp contrast to the conventional nickel-catalyzed Suzuki coupling with arylboronic acids, arylsulfamates unexpectedly displayed a higher reactivity than the corresponding tosylates in coupling with diarylborinic acids catalyzed by the nickel/phosphine catalyst system.

关键词： nickel phosphine cross-coupling diarylborinic acid aryl tosylate aryl sulfamate

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驾驶素质缺失测试眼状态的深度学习分类方法研究

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计算机工程 2025年第02期51卷 149-158页

作者：杨旺达万亚平邹刚闵晓珊王沂陆宇程南华大学计算机学院南华大学湖南中科助英智能科技研究院中南大学湘雅医院眼科学科室北京邮电大学国际学院

由驾驶员的不安全行为导致的交通事故占多数，针对驾驶认知素质特性的研究，搭建虚拟驾驶场景评估驾驶者的驾驶素质，可以最大限度地贴近现实环境和操作，唤醒驾驶者的潜在驾驶能力和应对能力。眼球运动可以极大程度地反映出驾驶者的认... 详细信息

由驾驶员的不安全行为导致的交通事故占多数，针对驾驶认知素质特性的研究，搭建虚拟驾驶场景评估驾驶者的驾驶素质，可以最大限度地贴近现实环境和操作，唤醒驾驶者的潜在驾驶能力和应对能力。眼球运动可以极大程度地反映出驾驶者的认知状态，但目前多数眼动状态识别研究主要关注在自然状态中基本视觉运动方向或者眼睑的闭合，识别类别的能力和效果对于驾驶场景的认知状态评估有限。收集了10类静态眼动方向的双眼数据，并提出融合注意力机制的多尺度眼状态图像识别模型。首先，使用部分卷积设计双分支特征融合模块，在加强模型特征提取能力的同时减少计算冗余；然后，在双分支特征融合的残差模块中嵌入改进的坐标注意力(CA)机制，提升模型对不同尺度特征的信息表征能力；最后，对模型的通道结构和数量进行调整，平衡模型的参数量与识别准确率。实验结果表明，所提方法在构建的10类眼动状态数据集上识别准确率达到95.1%,相比改进前的网络提高3.4个百分点；在Eye Chimera数据集和MRL眼睛数据集上的识别准确率分别为95.1%和98.95%,可以满足在虚拟驾驶测试环境下眼动状态识别的要求，并为进一步结合多参数分析驾驶素质缺失任务奠定基础。

关键词：驾驶认知眼状态图像分类特征融合注意力模块

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Highly Selective Fluorescence Turn-on Chemosensor Based on Naphthalimide Derivatives for Detection of Trivalent Chromium Ions

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Chinese Journal of Chemistry 2012年第12期30卷 2844-2848页

作者： Chen Zhijun Wang Limin zou gang Teng Mingshuang Yu Jianjun Shanghai Key Laboratory of Functional Materials Chemistry and Institute of Fine Chemicals East China University of Science and Technology Shanghai 200237 China College of Chemistry & Materials Engineering Wenzhou University Wenzhou Zhejiang 325035 China

A new fluorescent probe, NPQ-C, was synthesized. NPQ-C was based on the naphthalimide derivatives and exhibited high selectivity and sensitivity for Cr3＋ ions. As a Cr3＋-amplified fluorescent probe, Its fluorescence spectrum showed 5.5-fold enhancement in the intensity of the signal at 500 nm on binding with the Cr3＋. Based on the fluorescence titration spectra and Job＇s-plot analysis, binding mode of NPQ-C with Cr3＋ was proposed. Fluorescence intensity was linear with concentration of Cr3＋ cation in a range from 0 to 10 μmol·L-1. NPQ-C was also sensitive for Cr3＋. The detection limit was calculated to be 0.20 pmol.L-1 which indicated that NPQ-C was sensitive to Cr3＋.

关键词： trivalent chromium ions fluorescent probe fluorescence enhancement high selectivity, high sensitivity

Entanglement of Non-symmetric Two Atomic Qubits Induced by a Coherent State Field

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Communications in Theoretical Physics 2006年第1期45卷 67-70页

作者： LI Jun-gang zou Jian CAI Jin-Fang SHAO Bin Department of Physics School of Science Beijing Institute of Technology Beijing 100081 China

The entanglement of two atomic qubits, which are coupled to a coherent state field with different couplings, is studied. The dynamical evolution of the concurrence, which measures the degree of the entanglement between the two qubits, is plotted versus the scaled time gt. It is found that the two qubits can be entangled by the coherent state field even when they are initially prepared in the most mixed state, and for very weak field, the most mixed state can be; more easily entangled than some pure states. It is also found that the entanglement between the qubits sensitively depends on the relative difference of the atomic couplings and the mean photon number of the field.

关键词： entanglement mixed state coherent state field

Fatigue Strength Improvement of Welded Joint by Ultrasonic Peening in Ultra-Fine Grain Steel

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Journal of Iron and Steel Research International 2003年第3期10卷 64-66页

作者： TIAN Zhi-ling zou gang HE Chang-hong ZHANG Xiao-mu Central Iron and Steel Research Institute

The influence of rare earths (RE) on carbides in high carbon steel weld metal was studied by transmission electron microscope (TEM) and energy dispersive X ray microanalysis (EDX). It is found that rare earth markedly affects the quantity, morphology and distribution of carbides. The precipitating mechanism of carbides was proposed in which rare earth compounds with high surface energy serve as the nucleation sites for carbides in superheated liquid metal and the induced carbides are precipitated extensively and distributed evenly. The preferential precipitation of carbides decreases the carbon content in matrix, which is transformed into low carbon lath martensite after welds are chilled to room temperature.

关键词： rare earth metal carbide weld

Study on pitting process of 316L stainless steel by means of staircase potential electrochemical impedance spectroscopy

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International Journal of Minerals,Metallurgy and Materials 2011年第1期18卷 48-52页

作者： Zhi-jun Jia Cui-wei Du Cheng-tao Li zou Yi Xiao-gang Li School of Materials Science and Technology University of science and Technology Beijing Beijing 100083 China

Pitting corrosion of 316L stainless steel in NaCl solution was investigated by means of staircase potential electrochemical impedance spectroscopy（SPEIS）.The investigation focused on the transition of stainless steel from the passive state to pitting *** on the evolution of electrical parameters of the equivalent electrical circuit,it is suggested that the most probable mechanism of pit creation is the film breaking *** result demonstrates that staircase potential electrochemical impedance spectroscopy is an effective method for the investigation of pitting corrosion.

关键词： stainless steel passivation film steel corrosion pitting electrochemical impedance spectroscopy

Raman and UV-Vis Spectroscopy Applied to the Analysis of Liver Tissues from Rats with Myocardial Ischemia Induced by Isoproterenol

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Chemical Research in Chinese Universities 2011年第4期27卷 570-573页

作者： GAO Hai-cheng zou Ying-gang HUANG Yu-xin GAO Hai-mei CHEN Lei PEI Jin School of Pharmaceutical Sciences Jilin University Changchun 130012 P. R. China Department of Obstetrics ＆ Gynecology the Second Hospital of Jilin University Changchun 130041 P. R. China Basic Science College Changchun University of Technology Changchun 130012 P. R. China Key Laboratory for Molecular Enzymology and Engineering Ministry of Education Jilin University Changchun 130012 P. R. China

The application of the laser Raman spectroscopic（LRS） technique for the analysis of liver tissues from rats with myocardial ischemia induced by isoproterenol（ISO） was *** model of myocardial ischemia was established for rats induced by *** were randomly divided into four groups as normal group and myocardial ischemia *** observed the successful myocardial ischemia model via serum enzymes levels and hematoxylin-eosin（HE） staining,and detected the liver tissue of the rats from normal group and liver tissue of the rats from myocardial ischemia groups via UV-Vis spectroscopy（UV-Vis） and LRS,and the changes of the absorbance spectra were compared in the above four different *** results show that ISO can induce rat myocardial ischemia *** spectrum of normal liver tissue supernatant exhibits a strong absorption band at 968 nm,but no absorption band appears in the spectra of liver tissue supernatant solutions from the rats with myocardial ischemia induction after 2,12 and 72 h presented at 968 *** results show that Raman intensities of the precipitates suffered from ISO-treatment after 2,12 and 72 h were obviously increased compared with that of the precipitate of the liver tissue of the normal rats suffered from 0.9 g/L normal saline（NS） *** results indicate that LRS and UV-Vis can be harmless,nondestructive,rapid and effective methods for analyzing different pathological specimens of liver tissue from myocardial ischemia rats.

关键词： Laser Raman spectroscopy UV-Vis spectroscopy Isoproterenol Myocardial ischemia Rat Liver tissue

On Three-Dimensional Spiral Galaxies

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Chinese Physics Letters 2000年第12期17卷 932-934页

作者： LUO Xin-Lian PENG Qiu-He LONG Min PENG Fang zou Zhi-gang Department of Astronomy Nanjing UniversityNanjing 210093 Chinese Academy of Sciences-Peking University Joint Beijing Astrophysical Center Beijing UniversityBeijing 100871 Graduate Institute of Astronomy National Central UniversityChung-Li32054TaiwanChina

Density waves in 3D spiral galaxies are *** order to eliminate the forbidden region near the corotation in the grand-design galaxies,we assume that the perturbation satisfies the stable condition Q(r)>1 over all the disk except that at the ***,a new method is put forward here to determine some basic parameters of spiral *** apply it to our Galaxy,and the results are in good agreement with the previous results.

关键词： rotation. galaxies spiral