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橡胶胶囊硫化模具的结构设计

特种橡胶制品 2024年第1期45卷 45-49页

作者：王文博王涛杨兴云西北橡胶塑料研究设计院有限公司陕西咸阳712023 中国人民解放军93170部队陕西咸阳712023

以硬质铝合金2A14-T6作原材料设计并制做了橡胶胶囊充气式硫化模具;使用电脑软件ANSYS-Workbench建立了硫化模具热力耦合模型,分析了力学强度、模具厚度和热膨胀变形量并利用相关理论校验了分析结果。结果表明,设计的三个半硫化模具有... 详细信息

以硬质铝合金2A14-T6作原材料设计并制做了橡胶胶囊充气式硫化模具;使用电脑软件ANSYS-Workbench建立了硫化模具热力耦合模型,分析了力学强度、模具厚度和热膨胀变形量并利用相关理论校验了分析结果。结果表明,设计的三个半硫化模具有力保证了橡胶胶囊硫化成型过程中尺寸和厚度稳定;力学强度、模具厚度和热膨胀变形量校验结果符合技术要求;橡胶胶囊硫化模具满足用户使用要求。

关键词：橡胶胶囊充气式硫化模具半硫化模具硬质铝材相关理论校验

A novel adaptive modulation and coding strategy based on partial feedback for enhanced MBMS network

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The Journal of China Universities of Posts and Telecommunications 2008年第1期15卷 48-54页

作者： SHENG Yu PENG Mu-gen wang wen-bo School of Telecommunications Engineering Beijing University of Posts and Telecommunications Beijing 100876 China

The difference in link condition of broadcast/ multicast users and the limitation of uplink resource, make it difficult to utilize adaptive modulation and coding （AMC） in the enhanced multimedia broadcast and multicast service （E-MBMS） network. To obtain the improvement of system throughput, this study proposes an adaptive modulation and coding scheme based on partial feedback, by which only partial users whose channel qualities are lower than the system threshold need to make a response to the modulation coding scheme （MCS） adaptation procedure. By this investigation, an adaptive scheme can be introduced in the E-MBMS network. both the theoretical analysis and simulation results demonstrate the efficiency of the proposed strategy, in which the performance is close to the ideal one and has a significant throughput improvement when compared with that of the fixed MCS transmission scheme.

关键词： E-MBMS partial feedback AMC system throughput

Optimal transmission mode proportion for heterogeneous networks of cellular and device-to-device communications

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The Journal of China Universities of Posts and Telecommunications 2013年第4期20卷 21-27页

作者： LIU Zi-yang PENG Tao wang wen-bo Key Laboratory of Universal Wireless Communications Beijing University of Posts and Telecommunications

This paper discusses about the optimal mode allocation for the heterogeneous networks, in which the network can schedule users working in the device-to-device （D2D） mode or cellular mode. The D2D user is allowed to reuse the uplink resource of cellular system and the problem is formed as a sum-capacity optimization issue with outage constraints for both cellular and D2D links. The method for the optimal user proration is proved to be divided into three cases according to the total user density： when the total user density is small, the optimal proration trends to all users utilizing one mode; when the total user density is large, the optimal proration is all of users choosing D2D mode; and when the total user density situates in the between, there is a unique optimal transmission mode proportion for the hybrid networks to maximize its sumcapacity. The simulation results demonstrate the validity of the conclusions in the analysis part.

关键词： device-to-device mode proration sum-capacity optimization

Multiuser beamforming based on max SINR for downlink spatial multiplexing MIMO

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The Journal of China Universities of Posts and Telecommunications 2007年第3期14卷 28-33页

作者： MA Peng-fei ZHENG Kan wang wen-bo Wireless Signal Processing and Network Laboratory Beijing University ofPosts and Telecommunications Beijing 100876 China

In this article, a method based on max signal interference noise ratio（SINR） criterion is proposed, to mitigate the interuser interference for downlink multiuser spatial multiplexing multi-input multi-output（MIMO） systems. Unlike the zero forcing （ZF） scheme in which the SNR is decreased when the interference is eliminated completely, max SINR method makes a compromise between noise and interuser interference. When the number of substreams is larger than the difference between the number of base station antennas and the sum of interference mobile station antennas, the ZF is infeasible An existing coordinated TX-RX block diagonalization（COOR BD） method uses preprocessing at the receiver to cancel the interuser interference. However, it cannot obtain more receive diversity gain because of the preprocessing. Analysis and simulation show that the max SINR scheme has better performance than the ZF method. Moreover, when the ZF is infeasible, the max SINR scheme can obtain more receive diversity gain than COOR BD in the two-user case.

关键词： array signal processing beamforming MIMO systems spatial multiplexing

Adaptive modulation for SVD-based MIMO systems with outdated CSI

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The Journal of China Universities of Posts and Telecommunications 2009年第4期16卷 78-83页

作者： YAN Zhi wang wen-bo wang Xiao-ting ZHENG Kan Key Laboratory of Universal Wireless Communication Ministry of Education Beijing University of Posts and Telecommunications Beijing 100876 China

The performance of singular value decomposition （SVD）-based multiple-input multiple-output （MIMO） with adaptive modulation （AM） is dependent on the accuracy of the channel state information （CSI） at the transmitter and the receiver. However, for a time-varying channel, the CSI obtained at the transmitter or the receiver is incorrect owing to an inherent delay or error. A typical system employing SVD suffers degradation in capacity when outdated CSI is used to transmit data. This article first addresses the adaptive modulation MIMO system designed under perfect CSI assumption. Based on that, two scenarios of outdated CSI are investigated and analyzed. The effect of imperfect CSI on the system performance is focused on and a simple post processing SNR （pSNR） adjustment design is proposed on AM system in the two scenarios for reducing degradation in average spectral efficiency （ASE）. Simulation results show that these designs provide good performance in an adaptive way, and enable the adaptive MIMO system considerably more to be robust against CSI imperfection.

关键词： MIMO SVD adaptive modulation ohtdated CSI

干扰素诱导跨膜蛋白基因多态性与HBV感染程度的关联

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中华医院感染学杂志 2024年第12期34卷 1784-1788页

作者：王博文王强黄严春章革民陈华朱雄林武汉市新洲区人民医院感染内科湖北武汉430400 武汉市金银潭医院感染内科湖北武汉430048

目的探究干扰素诱导跨膜蛋白(IFITM)基因多态性与乙型肝炎病毒(HBV)感染程度的关系.方法选择2017年1月-2021年1月武汉市新洲区人民医院收治的104例HBV感染患者为研究组,按照HBV感染损伤肝功能的程度将患者分为A组(Child-Pugh A级,n=31)... 详细信息

目的探究干扰素诱导跨膜蛋白(IFITM)基因多态性与乙型肝炎病毒(HBV)感染程度的关系.方法选择2017年1月-2021年1月武汉市新洲区人民医院收治的104例HBV感染患者为研究组,按照HBV感染损伤肝功能的程度将患者分为A组(Child-Pugh A级,n=31)、B组(Child-Pugh B级,n=30)和C组(Child-Pugh C级,n=43),选择同一时间段内于医院进行体检的90名健康体检者为对照组;采用直接测序法检测IFITM基因多态性,并采用Logistic回归分析IFITM3基因多态性与HBV感染程度的关联.结果研究组IFITM3基因rs12252位点CC基因型、C等位基因频率高于对照组(P<0.05);不同HBV感染程度患者IFITM3基因rs12252位点CC基因型、C等位基因频率比较,差异有统计学意义(P<0.05);Logistic回归分析结果显示,IF-ITM3基因rs12252位点加性模式中携带CC基因型者HBV重度感染风险是携带TT基因型者的3.600倍(P<0.05),rs12252位点隐性模式中携带CC基因型者HBV重度感染风险是携带TT+TC基因型者的3.527倍(P<0.05);IFITM3基因rs12252位点CC基因型是HBV感染程度的危险因素(P<0.05).结论IFITM3基因rs12252位点多态性与HBV感染程度相关,CC基因型可能增加重度HBV感染风险.

关键词：干扰素诱导跨膜蛋白基因多态性乙型肝炎病毒感染程度关联性

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丝绸之路与茹河道沿线佛教遗存

陇东学院学报 2024年第4期35卷 31-34页

作者：刘治立王荣乐王博文陇东学院文学与历史文化学院甘肃庆阳745000 甘肃省庆阳林业学校甘肃庆阳745000 镇原县博物馆甘肃镇原744500

茹河道是汉唐时期丝绸之路交通网上非常重要的一段,其开通时间早,距离长安较近,沿线曾经上演过许多历史壮剧,留下许多中西文化交流的遗迹,众多的佛教石窟、碑塔及金石造像镶嵌在沿途的摩崖或道旁,静静地守望古道,折射出昔日中外文化交... 详细信息

茹河道是汉唐时期丝绸之路交通网上非常重要的一段,其开通时间早,距离长安较近,沿线曾经上演过许多历史壮剧,留下许多中西文化交流的遗迹,众多的佛教石窟、碑塔及金石造像镶嵌在沿途的摩崖或道旁,静静地守望古道,折射出昔日中外文化交融的盛况。

关键词：丝绸之路茹河道佛教遗存

Capacity of FH wireless multi-hop networks

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The Journal of China Universities of Posts and Telecommunications 2009年第6期16卷 78-83页

作者： WEI Dong-yan wang wen-bo PENG Mu-gen Key Laboratory of Universal Wireless Communication Ministry of Education Beij hag University of Posts and Telecommunications Beijing 100876 China

In this article,the capacity of wireless multi-hop networks with the frequency hopping（FH） technique is *** from the previous work based on non-spread spectrum（SS） system,this study is based on frequency hopping spread spectrum（FHSS） and the retransmission *** analysis results show that the normalized transport capacity decreases as 1/Mλ,when the total available frequency band is divided into M sub-bands for frequency hopping and the nodes are randomly distributed in space according to a Poisson point process with intensity λ .In this work,the best transmission range per hop to get the maximum capacity is also ***,the results summarize how the capacity of FH wireless multihop networks is affected by the outage probability,target signal to interference plus noise ratio（SINR） and other system parameters.

关键词： multihop frequency hopping capacity

Joint linear precoder and power allocation design for uplink MIMO systems with limited feedback

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The Journal of China Universities of Posts and Telecommunications 2009年第3期16卷 14-18页

作者： YAN Zhi wang wen-bo wang Jian-feng ZHENG Kan Key Laboratory of Universal Wireless Communication Ministry of Education Beijing University of Posts and Telecommunications Beijing 100876 China

In this article, the authors consider joint design of a linear precoder and power allocation for uplink multiuser multiple input multiple output （MIMO） communication systems with limited feedback to improve the bit error rate （BER） performance for all users. Precoder selection from the codebook set is directly based on the exact BER performance, instead of other suboptimal criteria, to achieve the optimal precoder matrix, but closed-form expressions may not exist in the view of power allocation based directly on the BER criterion. From this perspective, the authors propose the joint transmitter optimization algorithm for the consideration of precoder design, with total power constraint for asymptotic MBER （AMBER） criterion. In this AMBER criterion, a closed-form solution has been derived for power allocation with an optimal precoder. The simulation results show that the proposed joint design algorithm can achieve a much better performance than precoding with uniform power allocation and only consideration of power allocation.

关键词： MIMO linear precoder power allocation spatial multiplexing multiuser