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Outage-optimal relaying through opportunistic hybrid forward cooperation

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Science china(Information Sciences) 2011年第6期54卷 1264-1273页

作者： LI YuBo , YIN QinYe & WANG JunSong Ministry of Education key Lab for Intelligent networks and network Security, xi’an Jiaotong university, xi’an 71004., {4. 1. Ministry of Education key Lab for Intelligent networks and network Security Xi’an Jiaotong University Xi’an 710049 China

In this paper, a new scheme based on relay selection and data forwarding in multi-relay cooperative networks is introduced. Unlike most existing solutions focused on amplify-and-forward (AF) or decode-and-forward (DF) protocol separately, the proposed hybrid forward (HF) scheme takes advantage of both AF and DF protocols in relay forwarding. Based on theoretical analysis, a closed-form expression for the tight lower bound of its outage probability is derived, and further performance analysis is also presented. Then, in total power restricted networks, an optimal power allocation strategy between the source and the selected relay is developed to minimize the outage probability. Simulations are carried out finally, which validate the analysis and show that the HF scheme outperforms other existing ones in terms of outage probability.

关键词： cooperative diversity opportunistic cooperation outage probability power allocation diversity-multiplexing-tradeoff

Emerging clinical relevance of microbiome in cancer:promising biomarkers and therapeutic targets

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Protein & Cell 2024年第4期15卷 239-260页

作者： Jia-Hao Dai xi-Rong Tan Han Qiao Na Liu state key Laboratory of Oncology in South china Guangdong Key Laboratory of Nasopharyngeal Carcinoma Diagnosis and TherapyGuangdong Provincial Clinical Research Center for CancerSun Yat-sen University Cancer CenterGuangzhou 510050China

The profound influence of microbiota in cancer initiation and progression has been under the spotlight for years,leading to numerous researches on cancer microbiome entering clinical *** promising biomarkers and therapeutic targets,the critical involvement of microbiota in cancer clinical practice has been increasingly ***,recent progress in this field is *** describe the potential of tumor-associated microbiota as effective diagnostic and prognostic biomarkers,*** addition,we highlight the relationship between microbiota and the therapeutic efficacy,toxicity,or side effects of commonly utilized treatments for cancer,including chemotherapy,radiotherapy,and *** that microbial factors influence the cancer treatment outcome,we further summarize some dominating microbial interventions and discuss the hidden risks of these *** review aims to provide an overview of the applications and advancements of microbes in cancer clinical relevance.

关键词： microbiome cancer diagnosis prognosis therapy

Predication of Selective Ring-opening Hydrogenolysis for Furfuryl Alcohol to Produce Pentanediol over Dual-atom Catalysts

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Chemical Research in Chinese Universities 2024年第1期40卷 55-63页

作者： WANG Tingting WANG Jia xi Yongjie HU Bin LI Fuwei state key Laboratory for Oxo Synthesis and Selective Oxidation Lanzhou Institute of Chemical PhysicsChinese Academy of SciencesLanzhou 730000P.R.China university of Chinese Academy of Sciences Beijing 100049P.R.China

Selective activation of C-O bond is of fundamental importance in the precise conversion of oxygenates into value-added compounds in an atom-economic and sustainable manner, and meanwhile, the structurally well-defined dual-atoms catalysts (DACs) have been scarcely investigated in this field. In this study, a series of transition metal DACs anchored on nitrogen-doped graphene (TM2/NC, TM=Pt, Ir, Rh, Pd, Ru, Co, Ni and Cu) was constructed to make a comprehensive investigation of their selectivity in the hydrogenative transformation of furfuryl alcohol (FAL), an important biomass platform molecule, to 1,2-pentanediol (1,2-PeD) via selective cleavage of furanic C5-O bond, by density functional theory (DFT) calculations and microkinetic modeling. We found that Ir2/NC demonstrated a high selectivity for the cleavage of furanic C5-O bond to produce 1,2-PeD, while the production of THFAL or 1,5-pentanediol (1,5-PeD) on other TM2/NC catalysts are more favorable. Furthermore, we found that the selective C-O bond cleavage of FAL furan ring is affected by the orbital overlap between the d-orbitals of the anchored metal atoms and the p-orbitals of the adsorbed C atom in FAL, suggesting that the selectivity of the C-O bond cleavage is inextricably related with the electronic property of the anchored metals.

关键词： Furfuryl alcohol Hydrogenation Dual-atom catalyst Density functional theory(DFT)calculation

THERMOMECHANICAL RESPONSE OF SMA FIBER COMPOSITES WITH NON-UNIFORM TEMPERATURE DISTRIBUTION

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Acta Mechanica Solida Sinica 2003年第4期16卷 334-344页

作者： Zhang Zhen Wang Jian Shen Yapeng (The state key Laboratory of Mechanical Structural and Vibration,xi’an Jiaotong university,xi’an 71004.,china) The state key Laboratory of Mechanical Structural and Vibration Xi\'an Jiaotong University Xi\'an 710049 China

A micromechanics method based on the High-Order-Theory developed by Aboudi et *** used to predict the thermomechanical response of composites reinforced by shape memory alloy (SMA) fibers,and the non-uniform thermal distribution in composite arising from the process of heating or cooling is *** numerical development based on this model was coded to predict the thermomechanical response of shape memory alloy fiber/elastomer matrix composite subjected to thermal cycle *** the composite is heated,two heating ways,thermal gradients and heat source by passing an electric current through the SMA fibers are imposed on the composite *** cooling,the first thermal boundary condition and the second thermal boundary condition are subjected to the composite respectively.A series of stress distributions and temperature distributions for different instants are calculated to reveal the interaction between the SMA material and *** is useful to analyze and design the SMA actuator driven by heat source or the surface temperature.

关键词： shape memory alloy composites fiber

Novel strengthening methods for ultralightweight sandwich structures with periodic lattice cores

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Science china(Technological Sciences) 2010年第3期53卷 875-877页

作者： LU TianJian 1 &ZHANG QianCheng 2 1 MOE key Laboratory for Strength and Vibration,School of Aerospace,xi’an Jiaotong university,xi’an 71004.,china 2 state key Laboratory for Mechanical Behavior of Materials,School of Material Science and Engineering,xi’an Jiaotong university,xi’an 71004.,china 1. MOE key Laboratory for Strength and Vibration School of Aerospace Xi’an Jiaotong University Xi’an 710049 China2. State Key Laboratory for Mechanical Behavior of Materials School of Material Science and Engineering Xi’an Jiaotong University Xi’an 710049 China

Recent development of ultralightweight lattice-cored sandwiches is reviewed,with focus placed on various novel fabrication methods introduced to strengthen these structures,covering not only research results published... 详细信息

关键词： cellular metals strengthening method fabrication sandwich panels

MULTI-WATERMARKING SCHEME FOR GROUP USERS BASED ON VISUAL CRYPTOGRAPHY

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Journal of Electronics(china) 2005年第4期22卷 364-370页

作者： YuanZhonglan xiaGuangsheng WenQiaoyan YangYixian P.O.Box126 BeijingUniversityofPostsandTelecommunicationsBeijing100876China statekeyLaboratoryofintegratedservices{4. XidianUniversityXi＇an710071China

All watermarks are shared into shadow images using VCS(Visual Cryptography Scheme). Only one specific shadow (as a new watermark) is embedded into the host signal and the other ones are distributed to every user in each group as a key. In the watermarking extraction procedure, users in different group can obtain different watermark by combining their shadows with the extracted one from the watermarked signal. Analysis and experimental results show that the new watermarking method is novel, secure and robust.

关键词： Digital watermarking Visual cryptography Multi-watermarking

DISLOCATION ARRAY AT VARIOUS DEFORMING AND HARDENING STAGES OF STEEL 1035

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Acta Metallurgica Sinica(English Letters) 1995年第3期8卷 195-198页

作者： LUO Jingxi TAN Yuxu (state key Laboratory for Mechanical Behaviour of Materials,xi’an Jiaotong. university, china xi'an Jiaotong Univ Xi'an China

The alteration of dislocation arrays in the process of strain hardening for normalized carbon steel 1035 was investigated by transmission electron microscopy. At primary stage the separated dislocation lines tend to form tangles and networks, dislocation cells appear at the secondary stage, the amount of the cells increases significantly, its average dimension does not change and the cell walls become clear. The third stage of strain hardening was observed in the process from necking to fracture and shows a straight line segment on the lg σ -lg ε curve, at this time the dislocation cells become smaller and tend to form band structure.

关键词： strain hardening dislocation array cell structure steel 1035

Pairwise entanglement and local polarization of Heisenberg model

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Science china(Physics,Mechanics & Astronomy) 2008年第10期51卷 1515-1522页

作者： xi xiaoQiang1,2, ZHANG Tao3, YUE RuiHong3,4.& LIU WuMing2 1 Department of Applied Mathematics and Physics, xi’an Institute of Post and Telecommunications, xi’an 710061, china 2 Beijing National Laboratory for Condensed Matter Physics, Institute of Physics, Chinese Academy of Sciences, Beijing 100080, china 3 Institute of Modern Physics, Northwest university, xi’an 710069, china 4.Department of Physics, Ningbo university, Ningbo 315211, china Department of Applied Mathematics and Physics Xi’an Institute of Post and Telecommunications Xi’an 710061 China Beijing National Laboratory for Condensed Matter Physics Institute of Physics Chinese Academy of Sciences Beijing 100080 China Institute of Modern Physics Northwest University Xi’an 710069 China Department of Physics Ningbo University Ningbo 315211 China

The characteristics of pairwise entanglement and local polarization (LP) are dis-cussed by studying the ground state (states) of the Heisenberg XX model. The re-sults show that: the ground state (states) is (are) composed of the micro states with the minimal polarization (0 for even qubit and 1/2 for odd qubit); LP and the prob-ability of the micro state have an intimate relation, i.e. the stronger the LP, the smaller the probability, and the same LP corresponds to the same probability; the pairwise entanglement of the ground state is the biggest in all eigenvectors. It is found that the pairwise entanglement is decreased by the state degeneracy and the system size. The concurrence approaches a fixed value of about 0.34.2 (for odd-qubit chain) or 0.34.1 (for even-qubit chain) if the qubit number is large enough.

关键词： Heisenberg XX model local polarization pairwise entanglement

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IPv6网络路径容量测量方法研究

计算机科学 2011年第B10期38卷 312-314,349页

作者：唐军裴昌幸苏博西安电子科技大学综合业务网理论与关键技术国家重点实验室西安710071

分组离散技术是常用的路径容量测量方法之一,它通常采用连续发送策略来发送测量分组。然而该策略对发送带宽的利用率较低,影响了测量的准确性。针对IPv6网络环境,提出了一种新的基于分片机制的路径容量测量方法。该方法通过构造长度大... 详细信息

分组离散技术是常用的路径容量测量方法之一,它通常采用连续发送策略来发送测量分组。然而该策略对发送带宽的利用率较低,影响了测量的准确性。针对IPv6网络环境,提出了一种新的基于分片机制的路径容量测量方法。该方法通过构造长度大于路径最大传输单元的原始测量分组,迫使协议栈对该分组进行分片操作,生成长度相等的测量分片序列。实验结果表明,与经典的pathrate工具相比,该方法能够获得更小的源端分组离散以及更好的背景流量抑制能力。

关键词：路径容量分片机制分组离散背景流量网络测量