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A Raman Study of the Origin of Oxygen Defects in Hexagonal Manganite Thin Films

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Chinese Physics Letters 2012年第12期29卷 148-151页

作者： CHEN Xiang-Bai HIEN Nguyen Thi Minh yang in-sang LEE Daesu NOH Tae-Won Department of Nano Science&Mechanical Engineering and Nanotechnology Research Center Konkuk UniversityChungju 380-701Korea 2Department of Physics and Division of Nano-SciencesEwha Womans UniversitySeoul 120-750Korea 3ReCFIDepartment of Physics and AstronomySeoul National UniversitySeoul 151-747Korea

Oxygen defects are usually unavoidable when synthesizing oxide thin *** study the origin of the oxygen defects in hexagonal manganite HoMnO_(3) epitaxial thin films through Raman scattering *** results show that the oxygen defects in hexagonal HoMnO_(3) thin films have distinct effects on different phonon modes and on magnon *** analyses indicate that the oxygen defects in hexagonal HoMnO_(3) thin films mainly originate from the basal O3 and/or O4 oxygen ***,our analyses of oxygen defects predict that the Mn 3d orbitals would be more strongly hybridized with the apical O1 and/or O22p orbitals than the basal O3 and/or O42p *** prediction is consistent with our resonant Raman scattering study and earlier first-principle calculations of the electronic structures of hexagonal manganites.

关键词： spectroscopy. hexagonal Oxygen

Laser step-heating ^(40)Ar/^(39)Ar dating on young volcanic rocks

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Chinese Science Bulletin 2006年第23期51卷 2892-2896页

作者： WANG Fei HE Huaiyu ZHU Rixiang yang Liekun sang Haiqing WANG Yinglan Institute of Geology and Geophysics Chinese Academy of SciencesBeijing 100029 China

An attempt was made to use CO_2 laser step-heating method to date the late Pleistocene basaltic groundmass (DF-2) from Tengchong volcanic field. Among the fourteen heating steps, ten define a good inverse isochron (MSWD = 1.4) with an age of 32.2 ± 7.1 ka (2 σ).The inverse isochron also shows that the initial argon isotopic ratio is 297.1±2.0 (2σ) which is the same as the atmospheric argon at the 2σ error level. Study indicates that it is a useful means to date young volcanic groundmass with low K content by using CO_2 laser step-heating ^(40)Ar/^(39)Ar method.

关键词：二氧化碳激光步式加热玄武岩基质岩石学火山岩

Dynamic System Level Frequency Spectrum Allocation Scheme Based on Cognitive Radio Technology

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China Communications 2014年第7期11卷 84-91页

作者： WEI Zaixue yang Dacheng sang Lin Wireless Theories and Technologies Lab (WT&T) Beijing University of Posts and TelecommunicationsBeijing 100876 Beijing P. R. China

Cognitive radio is being widely discussed,and resource allocation scheme is drawing a lot of *** the existed resource allocation strategies have successfully enhanced spectrum efficiency,some critical challenges still remain unanswered such as the jointly consideration of the efficiency and fairness,the rational description of the spectrum resources,and the execution mode of the spectrum *** paper presents a system level dynamic frequency spectrum allocation scheme based on a central heterogeneous network architecture,evaluates the matching degree of the spectrum demand and the available spectrum resources with corresponding matrices,jointly considers the efficiency and fairness of different cognitive radio *** results and the application scenario are also presented and analyzed.

关键词： frequency spectrum allocationscheme heterogeneous network cognitiveradio spectrum resource manage center

An Improved NHPP Model with Time-Varying Fault Removal Delay

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Journal of Electronic Science and Technology of China 2008年第3期6卷 334-337页

作者： Xue yang Nan sang Hang Lei School of Computer Science and Engineering. University of Electronic Science and Technology of China （UESTC） Chengdu 610054 China

In this paper, an improved NHPP model is proposed by replacing constant fault removal time with time-varying fault removal delay in NHPP model, proposed by Daniel R Jeske. In our model, a time-dependent delay function is established to fit the fault removal process. By using two sets of practical data, the descriptive and predictive abilities of the improved NHPP model are compared with those of the NHPP model, G-O model, and delayed S-shape model. The results show that the improved model can fit and predict the data better.

关键词： Fault removal delay fault removal efficiency non-homogeneous Poisson process (NHPP) software reliability software reliability growth model

上瘾物品消费研究--从行为经济学视角看中国烟草消费市场

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探索与争鸣 2010年第6期 52-55页

作者：桑旸复旦大学社会发展与公共政策学院研究生上海200433

长期以来,国内外不同领域的研究人员一直致力于有害上瘾物品的消费研究,试图理解为什么人们要保持并继续发展实质上有害的上瘾行为,以期找到影响此类产品消费需求的因素。同时,政策上也有不少禁烟法规,并借助增加税收、教育宣传、医疗... 详细信息

长期以来,国内外不同领域的研究人员一直致力于有害上瘾物品的消费研究,试图理解为什么人们要保持并继续发展实质上有害的上瘾行为,以期找到影响此类产品消费需求的因素。同时,政策上也有不少禁烟法规,并借助增加税收、教育宣传、医疗辅助等手段干预消费者的决策,减少其对健康的危害。基于既有研究,从个人对上瘾物品的消费决策出发,通过对中国烟草消费市场现状的分析,试图深入理解消费者的上瘾行为,努力找到控制此类消费的有效途径,减少其对社会的外溢成本。上海今年将控烟纳入法律法规范畴,希望此举成为国家加强烟草消费有效干预的契机。

关键词：害品上瘾物品同群效应外部效应自我控制时间不一致性

Security-Aware Periodic-Write Scheduling for Mission-Critical Embedded Storage System

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Journal of Electronic Science and Technology of China 2009年第2期7卷 119-124页

作者： Wei Jiang Guang-Ze Xiong Zheng-Wei Chang Xu-yang Ding Nan sang The authors are with School of Computer Science University of Electronic Science and Technology of China Chengdu 610054 China

High quality of security and guaranteed real-time requirements are two key goals of mission- critical embedded storage systems. But most existing real-time disk scheduling algorithms do not consider improving security performance of disk requests. A security-aware periodic-write （SAPW） scheduling algorithm is proposed to judiciously select appropriate security level for each disk request to maximize security value of N periodic disk users, while without sacrificing timing constraint of each user. Simulation results show the significant effectiveness of SAPW algorithm, and the average security improvement is up to 223.6% over other three algorithms.

关键词： Index Terms-Disk scheduling embedded storagesystem real-time security-aware.

Raman spectroscopy studies of spin wave and spin flip in hexagonal manganites

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Raman spectroscopy studies of spin wave and spin flip in hex...