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基于渐近均匀化的力-电-湿耦合光滑有限元法

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吉林大学学报（工学版） 2024年第7期54卷 1876-1886页

作者：郑建校王文博刘金颂周立明李宇西安建筑科技大学机电工程学院西安710055 陕西省纳米材料与技术重点实验室西安710055 吉林大学机械与航空航天工程学院长春130022 上海宝冶集团有限公司上海201999

针对基于微观结构的力-电-湿多物理场耦合压电复合材料的力学特性分析问题,基于压电复合材料的基本方程、力-电-湿多物理场耦合效应,结合渐近均匀化方法预测的压电复合材料有效性能参数,提出基于渐近均匀化的力-电-湿耦合光滑有限元法... 详细信息

针对基于微观结构的力-电-湿多物理场耦合压电复合材料的力学特性分析问题,基于压电复合材料的基本方程、力-电-湿多物理场耦合效应,结合渐近均匀化方法预测的压电复合材料有效性能参数,提出基于渐近均匀化的力-电-湿耦合光滑有限元法。推导了力-电-湿耦合光滑有限元的动力学控制方程,并运用Wilson-θ法求解压电复合材料结构动力学问题,研究了湿度变化对结构固有频率和动力学响应的影响,并与有限元法的计算结果进行比较,验证了该方法的正确性和有效性。可见,该方法对分析压电复合材料元器件的多物理场耦合力学特性具有广阔的应用前景。

关键词：固体力学有限元法力-电-湿耦合渐近理论

Improved sample added LMMSE receiver based on interference mitigation for HSDPA downlink

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The Journal of China Universities of Posts and Telecommunications 2008年第2期15卷 39-44页

作者： CHE wen ZHAO Hui wang wen-bo Key Laboratory of Universal Wireless Communications Ministry of EducationBeijing University of Posts and Telecommunications Beijing 100876 China

In the downlink of wideband code division multiple access （WCDMA） or WCDMA- high speed downlink packet access （HSDPA） system, the frequency reuse factor is equal to 1, which leads to more possible co-channel interference from neighbor cells. In this situation, user equipment（UE） with traditional receiver will suffer from significant performance degradation at the edge of the cell. To solve this problem, a receiver structure considering interference mitigation has been proposed for long term evolution（LTE） of third-generation partnership project （3GPP）. Such receiver makes use of all the interfering cells＇ channel information to perform a linear minimum mean square error （LMMSE） equalization algorithm. In this article, an improved equalization algorithm is presented, which simply adds more samples to perform one equalization operation. Simulations show that the proposed algorithm can obtain a considerable performance improvement in frequency selective fading channel, with relative little additional complexity introduced.

关键词： LMMSE HSDPA equalizer

Physical layer security strategies for downlink heterogeneous cloud radio access networks

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The Journal of China Universities of Posts and Telecommunications 2014年第5期21卷 47-54,60页

作者： YAN Shi wang wen-bo Key Laboratory of Universal Wireless Communication Beijing University of Posts and Telecommunications

Cloud radio access networks （C-RANs） were proposed as promising solutions to increase both spectrum and energy efficiency performance in next generation wireless communication systems. Much works discussed the concrete implementation technology to justify the huge development potential of C-RAN. However, only a few litterateurs focused on characterizing the physical layer security in the downlink. The authors studied the physical layer security in downlink heterogeneous C-RAN systems in the article. To characterize the random deployment of remote radio units （RRUs） with single antenna configuration, the stochastic geometry is based to evaluate the proposals＇ secrecy transmission capacity performances, where the closed-form expressions are derived. Furthermore, two security strategies based on eavesdropper neutralization region to protect the target RRU user against eavesdropping were presented and analyzed. Simulation illustrates the secrecy transmission capacity performance limits on different system parameters. The presented security strategies show a significant enhancement on the secrecy performance.

关键词： C-RAN Poisson point process (PPP) physical layer security heterogeneous

一种计算机CPU被动式散热器的设计、仿真与实验研究

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陕西科技大学学报 2024年第4期42卷 133-141页

作者：王文博尚小标范会丽王先锋张群昆明理工大学机电工程学院云南昆明650500

针对当前高功率CPU静音散热需求,提出了一种新型被动式散热器.应用数值仿真与实验验证的方式对该散热器在不同加热功率下的温度、启动性能、热阻进行了研究.仿真结果表明:在120 W加热条件下,该散热器温度分布均匀,波动较小,最高温度仅为... 详细信息

针对当前高功率CPU静音散热需求,提出了一种新型被动式散热器.应用数值仿真与实验验证的方式对该散热器在不同加热功率下的温度、启动性能、热阻进行了研究.仿真结果表明:在120 W加热条件下,该散热器温度分布均匀,波动较小,最高温度仅为64.00℃,启动时间在900 s左右,平均接触热阻处在0.01~0.2℃/W之间.实验结果表明:在120 W加热条件下,该散热器最高温度仅为68.28℃,启动时间在900 s左右,平均接触热阻仅为0.11℃/W,满足计算机CPU在该功率下正常运行需求.

关键词：被动散热传热热阻热管计算机模拟芯片

Service behavior modeling and service behavior convergence-based radio resource scheduling in wireless systems

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The Journal of China Universities of Posts and Telecommunications 2011年第4期18卷 52-58,88页

作者： CAI wen-qi ZHANG Xing wang wen-bo School of Information and Communication Engineering Beijing University of Posts and Telecommunications Beijing 100876 China

With the development of wireless networks, the amount of multiple services increased sharply in recent years. High quality multiple services with low price are urgently needed especially in new generation mobile communication systems, e.g., 3G/LTE networks. It is important to enhance the availability of data service resources. Services have strong association which are used by clients with similar behavior habits in networks. Such feature results in service behavior convergence （SBC） and its utilization will enhance resource efficiency. This paper proposes two applications of service behavior： service prediction and a scheduling algorithm which enhances bandwidth efficiency. Convergence cells are classified according to SBC and hot-spot services are broadcasted separately in each convergence cell. It is demonstrated by stimulation that the bandwidth is saved 80% more than classical cellular system and nearly 20% more than traditional broadcasting system.

关键词： service behavior service prediction improved Apriori algorithm service behavior convergence

Performance Analysis of a Sectorized Distributed Antenna System with Reduced Co-Channel Interference

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The Journal of China Universities of Posts and Telecommunications 2006年第1期13卷 20-24页

作者： LIU Chen wang wen-bo Wireless Signal Processing and Networks Laboratory Beijing University of Posts and Telecommunications Beijing 100876 P. R. China

This paper proposes a sectorized distributed antenna system for the orthogonal frequency division multiplexing access system in order to both reduce the co-channel interference introduced by frequency reuse and maintain high spectral efficiency. The proposed system is composed of many 120-degree sectorized antennas that are uniformly distributed throughout the whole coverage area. Three adjacent sectors from different antennas share the same frequency band, which can be reused on the adjacent antennas. The new structure provides downlink interference divergence that greatly reduces co-channel interference and improves the system capacity, compared to the traditional cell structure with frequency reuse factor equal to 3. Multiple antennas broadcasting the same signal for a user using the same frequency, known as simulcasting, has been widely studied in distributed antenna systems. However, this paper demonstrates that simulcasting is not suitable for the close interfering structure. Multiple input multiple output distributed antenna systems might be a better choice.

关键词： distributed antenna system CCI OFDM OFDMA

Probabilistic greedy pursuit for streaming compressed spectrum sensing

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The Journal of China Universities of Posts and Telecommunications 2011年第5期18卷 15-21页

作者： LU Yang GUO wen-bin wang Xing wang wen-bo Key Laboratory of Universal Wireless Communication Ministry of EducationBeijing University of Posts and TelecommunicationsBeijing 100876China

This paper presents a probabilistic greedy pursuit （PGP） algorithm for compressed wide-band spectrum sensing under cognitive radio （CR） scenario. PGP relies on streaming compressed sensing （CS） framework, which differs from traditional CS processing way that only focuses on fixed-length signal＇s compressive sampling and reconstruction. It utilizes analog-to-information converter （AIC） to perform sub-Nyquist rate signal acquisition at the radio front-end （RF） of CR, the measurement process of which is carefully designed for streaming framework. Since the sparsity of wide-band spectrum is unavailable in practical situation, PGP introduces the probabilistic scheme by dynamically updating support confidence coefficient and utilizes greedy pursuit to perform streaming spectrum estimation, which gains sensing performance promotion progressively. The proposed algorithm enables robust spectrum estimation without the priori sparsity knowledge, and keeps low computational complexity simultaneously, which is more suitable for practical on-line applications. Various simulations and comparisons validate the effectiveness of our approach.

关键词： cognitive radio wide-band spectrum sensing streaming compressed sensing probabilistic greedy pursuit support confidence coefficient

Distributed scheduling based on polling policy with maximal spatial reuse in multi-hop WMNs

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The Journal of China Universities of Posts and Telecommunications 2007年第3期14卷 22-27页

作者： wang Kun PENG Mu-gen wang wen-bo Wireless Signal Processing and Network Laboratory Beijing University of Posts and Telecommunications Beijing 100876 China

The scheduling algorithm based on the three-way handshaking scheme in IEEE 802.16d-2004 standard has some serious problems because of the complexity of the algorithm and low scheduling efficiency. To enhance the scheduling efficiency and improve the performance of multi-hop wireless mesh networks （WMNs）, one distributed scheduling algorithm that can maximize the spatial and time reuse with an interference-based network model is proposed. Compared to the graph-based network model, the proposed network model can achieve a better throughput performance with maximal spatial reuse. Furthermore, this proposed scheduling algorithm also keeps fairly scheduling to all links, with a priority-based polling policy. both the theoretical analysis and simulation results show that this proposed distributed scheduling algorithm is simple and efficient.

关键词： WMNs distributed scheduling algorithm spatial reuse polling policy

Efficient delay based scheduling with fairness in multi-hop wireless mesh networks

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The Journal of China Universities of Posts and Telecommunications 2007年第4期14卷 82-87页

作者： wang Kun PENG Mu-gen wang wen-bo Wireless Signal Processing and Network Laboratory Beijing University ofPosts and Telecommunications Beijing 100876 China

Some scheduling algorithms have been designed to improve the performance of multi-hop wireless mesh networks （WMNs） recently. However the end-to-end delay is seldom considered as the complexity of multi-hop topology and open wireless shared channel. This article proposes an efficient delay based scheduling algorithm with the concept of buffer-data- hops. Considering the demand satisfaction factor（DSF）, the proposed algorithm can also achieve a good fairness performance. Moreover, with the interference-based network model, the scheduling algorithm can maximize the spatial reuse, compared to those graph-based scheduling algorithms. Detailed theoretical analysis shows that the algorithm can minimize the end-to-end delay and make a fair scheduling to all the links.

关键词： WMNs scheduling algorithm delay fairness,spatial reuse