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channel Sandstone Architecture Characterization by Seismic Simulation

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Journal of Earth Science 2019年第4期30卷 799-808页

作者： Hongwei Liang Xiaoqing Zhao Longxin Mu Zifei Fan Lun Zhao Shenghe Wu Research Institute of Petroleum Exploration and Development Beijing 100083China Geophysical Research Center Bureau of Geophysical Prospecting IncorporationCNPCBaoding 072751China College of Geosciences China University of PetroleumBeijing 102249China

To describe the distribution of sandstone reservoirs between wells finely,this paper takes the sandstone reservoir of Layer Nm II-4 in Qinhuangdao 32-6 Oilfield for example,and uses the seismic forward simulation and well loggings to study the channel sandstone reservoir. Under the guidance of the modern rivers and outcrops sandstone distribution pattern,the predicting limitations of the seismic forward simulation about channel sandstone boundaries such as mudstone interlayer between channel sandstone and elevation distance between adjacent channel sandstone are clear. The research shows that the mudstone interlayer can be described by seismic forward simulation seismic when the mudstone interlayer is thicker than 2 m and the channel sandstone is thicker than 10 m because of the appearance of the seismic peak when the main frequency of seismic data is nearly 60 Hz. And the elevation distance between adjacent channel sandstone can be described by the seismic forward simulation when elevation distance is longer than 6 m and the channel sandstone is thicker than 10 m because of the appearance of the seismic peak. And the seismic waveform features of single channel sandstone boundaries such as elevation distance between channels,overbank sandstone and abandoned channels. Under the study mentioned above,the single channel boundaries are described in Layer Nm II-4 of Qinhuangdao 32-6 Oilfield,and the predicting boundaries are confirmed by the chemical tracers. The results show that the channel sandstone reservoir architecture characterization can be improved by the seismic forward simulation.

关键词： architecture overbank sandstone seismic abandoned channel

channel Modeling and Performance Analysis for UAV Relay Systems

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China Communications 2018年第12期15卷 89-97页

作者： Xiaomin Chen Xujun Hu Qiuming Zhu Weizhi Zhong Bin Chen College of Electronic and Information Engineering Nanjing University of Aeronautics and Astronautics College of Astronautics Nanjing University of Aeronautics and Astronautics College of Computer Science and Technology Nanjing University of Aeronautics and Astronautics

In this paper, a multi-hop relay channel model based on unmanned aerial vehicles(UAVs) is established by taking into account of the propagation loss, shadowing, and multi-path fading. Based on the proposed channel model, the cascaded propagation loss of relay link and the cascaded probability density function(PDF) of channel fading are derived. Moreover, the theoretical performance of the UAV-based relay system, i.e., the outage probability, bit error rate(BER), and channel capacity, is also analysed and derived. Simulation results show agreement with theoretical results for the hill, mountain, and sea scenarios, indicating the accuracy of both the simulations and derivations.

关键词： UAV relay system relay channel model outage probability bit error rate channel capacity

channel Estimation for One-Bit Massive MIMO Based on Improved CGAN

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Journal of Communications and Information Networks 2022年第2期7卷 214-220页

作者： Yongli An Jinking Yue Lei Chen Zhanlin Ji School of Artificial Intelligence North China University of Science and TechnologyTangshan 063000China. Key Laboratory of Industrial Intelligent Perception of Hebei Province Tangshan 063000China

In the one-bit massive multiple-input multiple-output(MIMO)channel scenario,the accurate channel estimation becomes more difficult because the signals received by the low-resolution analog-to-digital converters(ADC)are quantized and affected by channel ***,a one-bit massive MIMO channel estimation method is proposed in this *** channel matrix is regarded as a two-dimensional *** order to enhance the significance of noise features in the image and remove them,the channel attention mechanism is introduced into the conditional generative adversarial network(CGAN)to generate channel images,and im-prove the loss *** simulation results show that the improved network can use a smaller number of pilots to obtain better channel estimation *** the same number of pilots and signal-to-noise ratio(SNR),the channel estimation accuracy can be improved by about 7.5 dB,and can adapt to the scenarios with more antennas.

关键词： channel estimation massive MIMO condi-tional generative adversarial network attention mecha-nism denoising

channel estimation for multi-panel millimeter wave MIMO based on joint compressed sensing

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The Journal of China Universities of Posts and Telecommunications 2020年第6期27卷 1-7,29页

作者： Liu Xu Xie Yang College of Telecommunications and Information Engineering Nanjing University of Posts and TelecommunicationsNanjing 210023China Jiangsu Key Laboratory of Wireless Communications Nanjing University of Posts and TelecommunicationsNanjing 210023China

channel state information(CSI)is essential for downlink transmission in millimeter wave(mmWave)multiple input multiple output(MIMO)***-panel antenna array is exploited in mmWave MIMO system due to its superior *** channel estimation algorithms are proposed in this paper,named as generalized joint orthogonal matching pursuit(G-JOMP)and optimized joint orthogonal matching pursuit(O-JOMP)for multi-panel mmWave MIMO system based on the compressed sensing(CS)theory.G-JOMP exploits common sparsity structure among channel response between antenna panels of base station(BS)and users to reduce the computational complexity in channel estimation.O-JOMP algorithm is then developed to further improve the accuracy of channel estimation by optimal panel selection based on the power of the received *** results show that the performance of the proposed algorithms is better than that of the conventional orthogonal matching pursuit(OMP)based algorithm in multi-panel mmWave MIMO system.

关键词： channel estimation multi-panel MIMO millimeter wave joint orthogonal matching pursuit common sparsity

channel Estimation for Full-Duplex Relay Transmission in Cloud Radio Access Networks

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China Communications 2015年第11期12卷 35-42页

作者： HU Chunjing LI Jian MAO Zhendong BAN Yourong Key Laboratory of Universal Wireless Communication Ministry of EducationBeijing University of Posts and Telecommunications Department of Electrical Engineering University of Arkansas

Relay in full-duplex(FD) mode can achieve higher spectrum efficiency than that in half-duplex mode,while it is crucial to suppress relay self-interference to ensure transmission quality which requires instantaneous channel state information(CSI). In this paper,the channel estimation issue in FD amplify-andforward relay networks is considered,where the training-based estimation technique is adopted. Firstly,the least square(LS) estimation is implemented to obtain composite channel coefficients of source-relay-destination(SRD) channel and relay loop-interference(LI) channel in order to assist destination in performing data detection. Secondly,both LS and maximum likelihood estimation methods are utilized to perform individual channel estimation aiming at supporting successive interference cancelation at destination. Finally,simulation results demonstrate the effectiveness of both composite and individual channel estimation,and the presented ML method can achieve lower MSEs than LS solution.

关键词： channel estimation full-duplex cloud radio access networks

channel adaptive rate control for energy optimization

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2006年第z1期7卷 82-88页

作者： BLANCH Carolina POLLIN Sofie LAFRUIT Gauthier EBERLE Wolfgang Interuniversity Microelectronics Center Kapeldreef 75 Leuven 3001Belgium Interdisciplinary Institute for BroadBand TechnologyGent-Ledeberg B-9050Belgium Interuniversity Microelectronics Center Kapeldreef 75 Leuven 3001Belgium Interdisciplinary Institute for BroadBand TechnologyGent-Ledeberg B-9050 Belgium Department of Electrical EngineeringK.U.LeuvenESAT/INSYSBelgium Interuniversity Microelectronics Center Kapeldreef 75 Leuven 3001Belgium

Low energy consumption is one of the main challenges for wireless video transmission on battery limited devices. The energy invested at the lower layers of the protocol stack involved in data communication, such as link and physical layer, represent an important part of the total energy consumption. This communication energy highly depends on the channel conditions and on the transmission data rate. Traditionally, video coding is unaware of varying channel conditions. In this paper, we propose a cross-layer approach in which the rate control mechanism of the video codec becomes channel-aware and steers the instantaneous output rate according to the channel conditions to reduce the communication energy. Our results show that energy savings of up to30% can be obtained with a reduction of barely 0.1 dB on the average video quality. The impact of feedback delays is shown to be small. In addition, this adaptive mechanism has low complexity, which makes it suitable for real-time applications.

关键词： Rate control, channel condition, Communication energy

Numerical study on turbulent mixed convection in a vertical plane channel using hybrid RANS/LES and LES models

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Chinese Journal of Chemical Engineering 2020年第1期28卷 1-8页

作者： Puxian Ding Shuangfeng Wang Kai Chen Key Laboratory of Enhanced Heat Transfer and Energy Conservation of the Ministry of Education School of Chemistry and Chemical EngineeringSouth China University of TechnologyGuangzhou 510640China

Two Delayed-Detached Eddy Simulation(DDES) models, and a Large-Eddy Simulation(LES) model are used to investigate the turbulent flows and mixed convection between a hot plate and a cold plate via the software FLUENT. The two DDES models include Production-limited DDES(PL-DDES) and Improved DDES(IDDES) *** Wall-Adapting Local Eddy-Viscosity(WALE) model is the used LES model. The numerical computations are performed at Reynolds number Reb= 4494 and different Richardson numbers Ri = 0.025, 0.048, 0.1. The comparing data is from the Direct Numerical Simulation(DNS) at Reb= 4494 and Ri = 0.048. The comparison reveals that the two DDES models have better performance in predicting time-averaged parameters than the WALE model in the aiding flow. The best predicted time-averaged results are obtained by the PL-DDES model in the opposing flow. Furthermore, the results of different Ri obtained by the PL-DDES model agree well with the DNS data.

关键词： Turbulent mixed convection Hybrid RANS/LES model PL-DDES model WALE model Vertical plane channel

Effects of dimensional wall temperature on velocity-temperature correlations in supersonic turbulent channel flow of thermally perfect gas

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Science China(Physics,Mechanics & Astronomy) 2019年第6期62卷 64-74页

作者： XiaoPing Chen XinLiang Li ZuChao Zhu Key Laboratory of Fluid Transmission Technology of Zhejiang Province Zhejiang Sci-Tech University Key Laboratory of High Temperature Gas Dynamics Institute of Mechanics Chinese Academy of Sciences School of Engineering Science University of Chinese Academy of Sciences

Direct numerical simulations of temporally evolving supersonic turbulent channel flows of thermally perfect gas are conducted at Mach number 3.0 and Reynolds number 4800 for various values of the dimensional wall temperature to study the influence of the latter on the velocity-temperature correlations. The results show that in a fully developed turbulent channel flow, as the dimensional wall temperature increases, there is little change in the mean velocity, but the mean temperature decreases. The mean temperature is found to be a quadratic function of the mean velocity, the curvature of which increases with increasing dimensional wall temperature. The concept of "recovery enthalpy" provides a connection between the mean velocity and the mean temperature, and is independent of dimensional wall temperature. The right tails of probability density function of the streamwise velocity fluctuation grows with increasing dimensional wall temperature. The dimensional wall temperature does not have a significant influence on the Reynolds analogy factor or strong Reynolds analogy(SRA). The modifications of SRA by Huang et al. and Zhang et al. provide reasonably good results, which are better than those of the modifications by Cebeci and Smith and by Rubesin.

关键词： direct numerical simulation velocity-temperature correlation supersonic flow channel flow thermally perfect gas strong Reynolds analogy

Experimental repetitive quantum channel simulation

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Science Bulletin 2018年第23期63卷 1551-1557页

作者： Ling Hu Xianghao Mu Weizhou Cai Yuwei Ma Yuan Xu Haiyan Wang Yipu Song Chang-Ling Zou Luyan Sun Center for Quantum Information Institute for Interdisciplinary Information Sciences Tsinghua University Key Laboratory of Quantum Information CAS University of Science and Technology of China

Universal control of quantum systems is a major goal to be achieved for quantum information processing,which demands thorough understanding of fundamental quantum mechanics and promises applications of quantum technologies. So far, most studies concentrate on ideally isolated quantum systems governed by unitary evolutions, while practical quantum systems are open and described by quantum channels due to their inevitable coupling to environment. Here, we experimentally simulate arbitrary quantum channels for an open quantum system, i.e. a single photonic qubit in a superconducting quantum *** arbitrary channel simulation is achieved with minimum resource of only one ancilla qubit and measurement-based adaptive control. By repetitively implementing the quantum channel simulation,we realize an arbitrary Liouvillian for a continuous evolution of an open quantum system for the first time. Our experiment provides not only a testbed for understanding quantum noise and decoherence,but also a powerful tool for full control of practical open quantum systems.

关键词： Quantum channel simulation Open quantum system Adaptive quantum control Superconducting quantum computation