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Energy-efficient Butler-matrix-based hybrid beamforming for multiuser mm Wave MIMO system

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Science China(Information Sciences) 2017年第8期60卷 48-57页

作者： Jiahui LI Limin xiao xibin XU Xin SU Shidong ZHOU State Key Laboratory on Microwave and Digital Communications Tsinghua National Laboratory for Information Science and TechnologyDepartment of Electronic Engineering Tsinghua University

In order to reduce the cost and power consumption of radio frequency(RF) chains in a millimeterwave(mm Wave) multiple-input multiple-output(MIMO) system, hybrid analog/digital beamforming(HBF)can be utilized to reduce the number of RF chains. The HBF consists of an analog beamforming(ABF) stage and a digital beamforming(DBF) stage. The ABF is always realized by using phase shifters and the DBF is done in a low-dimensional digital domain. However, phase shifters have several drawbacks, such as high power consumption and inconsistency of insertion loss. In this paper, we propose an energy-efficient HBF structure to handle these problems, which utilizes the Butler phase shifting matrix in the ABF stage. With the Butlermatrix-based ABF, several fixed beam directions can be obtained, and the best beam directions of different Butler matrices can be chosen by using exhaustive search. To reduce the high complexity of exhaustive search,we further provide a low complexity HBF algorithm. Simulations under the conditions of perfect channel state information(CSI) and estimated CSI verify the effectiveness of our proposed Butler-matrix-based HBF structure and related algorithms.

关键词： Butler matrix energy-efficient hybrid beamforming MIMO mm Wave multiuser

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医学生医患沟通能力培养的实践与研究

中国高等医学教育 2017年第1期 61-62页

作者：肖希斌丁卢胤黄连生浙江大学医学院附属第二医院浙江杭州310009

良好的医患沟通能力是医学生成为一名合格医生不可缺少的条件。从临床教学角度,探讨医学生医患沟通能力存在的问题及提高医学生医患沟通能力的方法。通过对学员培训前医患沟通能力的评估,进行个性化的培训,提高学员的医患沟通能力,为日... 详细信息

良好的医患沟通能力是医学生成为一名合格医生不可缺少的条件。从临床教学角度,探讨医学生医患沟通能力存在的问题及提高医学生医患沟通能力的方法。通过对学员培训前医患沟通能力的评估,进行个性化的培训,提高学员的医患沟通能力,为日后的工作创造更好的条件,更好地服务病患。

关键词：医患沟通医学生医患关系

Sectorization based pilot reuse for improving net spectral efficiency in the multicell massive MIMO system

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Science China(Information Sciences) 2016年第2期59卷 97-111页

作者： Jiahui LI Limin xiao xibin XU Shidong ZHOU State Key Laboratory on Microwave and Digital Communications Tsinghua National Laboratory for Information Science and Technology Department of Electronic Engineering Tsinghua University

A sectorization method using the uniform circular array(UCA) is proposed to improve the net spectral efficiency(SE) of the multicell massive MIMO system, which is an important index for evaluating the performance of a communication system. We derive the ergodic achievable uplink net SE per cell of a general sectorized system and obtain its deterministic approximation based on the large random matrix *** weight matrices are considered for the sectorized system and the one with the best performance is utilized for further analysis. The consistency of the deterministic approximation with the result of Monte-Carlo simulation is proved at the same time. At last, numerical results indicate that the net SE per cell can be greatly improved compared to the conventional multicell massive MIMO system, which validates the effectiveness of the sectorization method. Moreover, comparisons with other pilot reuse methods are also made in this paper.

关键词： massive MIMO multicell net SE pilot reuse sectorization UCA

Hierarchical path planning for multi-arm spacecraft with general translational and rotational locomotion mode

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Science China(Technological Sciences) 2023年第4期66卷 1180-1191页

作者： YUE ChengFei LIN Tao ZHANG xiao CHEN XueQin CAO xibin Institute of Space Science and Applied Technology Harbin Institute of Technology ShenzhenShenzhen 518055China Research Center of the Satellite Technology Harbin Institute of TechnologyHarbin 150001China

On-orbit construction and maintenance technology will play a significant role in future space *** dexterous multifunctional spacecraft equipped with multi-arm,for instance,Spider Fab Bot,has attracted a great deal of focus due to its versatility in completing these *** such engineering practice,point-to-point moving in a complex environment is the fundamental *** paper investigates the three-dimensional point-to-point path planning problem,and a hierarchical path planning architecture is developed to give the trajectory of the multi-arm spacecraft effectively and *** the proposed 3-level architecture,the high-level planner generates the global constrained centric trajectory of the spacecraft with a rigid envelop assumption;the middle-level planner contributes the action sequence,a combination of the newly developed general translational and rotational locomotion mode,to cope with the relative position and attitude of the arms about the centroid of the spacecraft;the low-level planner maps the position/attitude of the end-effector of each arm from the operational space to the joint space ***,the simulation experiment is carried out,and the results verify the effectiveness of the proposed three-layer architecture path planning strategy.

关键词： multi-arm spacecraft path planning hierarchical architecture locomotion mode translational locomotion rotational locomotion

Analysis of BAC_5 mcAb-Related Epitope Using Random Peptide library

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The Chinese-German Journal of Clinical Oncology 2003年第1期2卷 39-41,61页

作者：肖锡宾张昌卿张颖张如华李经略冯凯涛孙韵叶永照广州中山大学肿瘤医院 510060

Objective To identify epitope relating to BAC 5 mcAb, a kind of monoclonal antibody (mcAb) located on the surface of nasopharyngeal carcinoma (NPC) cells. Methods Using BAC 5 mcAb as a selected target, the 3 rounds of biopanning to a 12 mer random peptide library (RPL) presented by M13 phages were carried out. The positive M13 phage clones were chosen and confirmed with sandwich ELISA for antibody capture and competitive assay. The exogenous DNA fragments in the positive/negative M13 phages were sequenced to deduce and compare the order of the amino acids of exogenous peptides among the phage clones. Results 77% (35/45) of the phages eluted from the 3rd round of biopnning could be captured by BAC 5 mcAb. The 3 kinds of the peptides were displayed by M13 phages from the 8 positive clones identified with competitive assay. The same character of '-P-V-'structure existed near N-terminus of the 3 different peptides, i.e. -H-Q-S-H-Y-P-Y-P-V-V-S-L- (4/8) -Q-N-Q-A-W-F-S-Q-P-V-R-M- (3/8) and T-Q-A-Y-K-G-F-P-V-L-P-S- (1/8) in comparison with the peptide ' -N-H-Q-S-T-F-W-Q-K-W-T-A-' displayed by M13 phages from the negative clones (6/6). Conclusion BAC 5 mcAb can recognize the 3 kinds of the peptides with-P-V-structure near N-terminus. These peptides mimic the structure of the epitope on the surface of NPC cells recognized by BAC 5 mcAb.

关键词： epitope random peptide library monoclonal antibody nasopharyngeal carcinoma

Low-Complexity Soft-Output Detection for Massive MIMO Using SCBiCG and Lanczos Methods

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China Communications 2015年第S1期12卷 9-17页

作者： xiao Chiyang SU Xin ZENG Jie RONG Liping XU xibin WANG Jing Tsinghua University

Massive MIMO is a promising technology to improve spectral efficiency, cell coverage, and system capacity for 5G. However, these benefits take place at great cost of computational complexity, especially in systems with hundreds of antennas at the base station. This paper aims to address the minimum mean square error(MMSE) detection in uplink massive MIMO systems utilizing the symmetric complex bi-conjugate gradients(SCBiCG) and the Lanczos method. Both the proposed methods can avoid the large scale matrix inversion which is necessary for MMSE, thus, reducing the computational complexity by an order of magnitude with respect to the number of user equipment. To enable the proposed methods for soft-output detection, we also derive an approximating calculation scheme for the log-likelihood ratios(LLRs), which further reduces the complexity. We compare the proposed methods with existing exact and approximate detection methods. Simulation results demonstrate that the proposed methods can achieve near-optimal performance of MMSE detection with relatively low computational complexity.

关键词： massive MIMO soft-output detection SCBiCG Lanczos low-complexity

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水厂排泥水固体通量及微砂增效絮凝沉淀试验

净水技术 2024年第S2期43卷 29-34页

作者：郭智刚刘正雄肖曦彬吴振元都正良柴晓利深圳市政集团有限公司广东深圳518131 同济大学环境科学与工程学院上海200092

城市水厂在净水过程中产生的大量排泥废水,不仅影响水厂的正常运行,还会对生态环境卫生造成较大威胁。为探索一种经济高效的排泥水絮凝沉降技术,试验取上海市某水厂沉淀池排泥水进行自然沉降试验,探究微砂增效阳离子型聚丙烯酰胺(CPAM)... 详细信息

城市水厂在净水过程中产生的大量排泥废水,不仅影响水厂的正常运行,还会对生态环境卫生造成较大威胁。为探索一种经济高效的排泥水絮凝沉降技术,试验取上海市某水厂沉淀池排泥水进行自然沉降试验,探究微砂增效阳离子型聚丙烯酰胺(CPAM)絮凝处理对排泥水沉降性能及其固体通量的影响规律。结果表明:低浓度排泥水的自然沉降速率较大,静沉固体通量高,当到达压密点后沉降速率变小,沉降曲线发生明显变化;随着排泥水浓度增加,自然沉降速率减小,但具有较大的向下流排泥固体通量。单独投加CPAM对于高浓度排泥水沉降性的改善作用有限,而采用60%微砂增效1.0 mg CPAM/g絮凝处理对低、高浓度排泥水的沉降性均具有良好的促进效果,并产生较高的总固体通量,是一种高效的絮凝浓缩技术。该试验结果为水厂排泥水的高效絮凝处理提供了重要参考。

关键词：排泥水阳离子型聚丙烯酰胺(CPAM) 絮凝沉淀微砂增效固体通量

Landslide Hazard Mapping Using GIS and Weight of Evidence Model in Qingshui River Watershed of 2008 Wenchuan Earthquake Struck Region

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Journal of Earth Science 2012年第1期23卷 97-120页

作者： Chong Xu Xiwei Xu Fuchu Dai Jianzhang xiao xibin Tan Renmao Yuan Key Laboratory of Active Tectenics and Volcano Institute of GeologyChina Earthquake AdministrationBeijing 100029China Institute of Geology and Geophysics Chinese Academy of SciencesBeijing 100029China

Tens of thousands of landslides were triggered by May 12, 2008 earthquake over a broad area. The main purpose of this article is to apply and verify earthquake-triggered landslide hazard analysis techniques by using weight of evidence modeling in Qingshui （清水） River watershed, Deyang （德阳） City, Sichuan （四川） Province, China. Two thousand three hundred and twenty-one landslides were interpreted in the study area from aerial photographs and multi-source remote sensing imageries post-earthquake, verified by field surveys. The landslide inventory in the study area was established. A spatial database, including landslides and associated controlling parameters that may have influence on the occurrence of landslides, was constructed from topographic maps, geological maps, and enhanced thematic mapper （ETM＋） remote sensing imageries. The factors that influence landslide occurrence,such as slope angle, aspect, curvature, elevation, flow accumulation, distance from drainages, and distance from roads were calculated from the topographic maps. Lithology, distance from seismogenic fault, distance from all faults, and distance from stratigraphic boundaries were derived from the geological maps. Normalized difference vegetation index （NDV1） was extracted from ETM＋ images. Seismic intensity zoning was collected from Wenchuan （汶川） Ms8.0 Earthquake Intensity Distribution Map published by the China Earthquake *** hazard indices were calculated using the weight of evidence model, and landslide hazard maps were calculated from using different controlling parameters cases. The hazard map was compared with known landslide locations and verified. The success accuracy percentage of using all 13 controlling parameters was 71.82%. The resulting landslide hazard map showed five classes of landslide hazard, i.e., very high, high, moderate, low, and very low. The validation results showed satisfactory agreement between the hazard map and the existing landslides distribution d

关键词： Wenchuan earthquake landslides weight of evidence Geographic Information Systems(GIS) landslide hazard mapping.

Resequencing of sweetpotato germplasm resources reveals key loci associated with multiple agronomic traits

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Horticulture Research 2023年第1期10卷 128-139页

作者： Shizhuo xiao xibin Dai Lingxiao Zhao Zhilin Zhou Lukuan Zhao Pan Xu Bingqian Gao An Zhang Donglan Zhao Rui Yuan Yao Wang Jie Wang Qinglian Li Qinghe Cao Jiangsu Xuzhou Sweetpotato Research Center/Sweetpotato Research Institute Chinese Agricultural Academy of SciencesXuzhou 221131China College of Pastoral Agriculture Science and Technology Lanzhou UniversityLanzhou 730020China

Sweetpotato is an important crop that exhibits hexaploidy and high heterozygosity,which limits gene mining for important agronomic ***,314 sweetpotato germplasm resources were deeply resequenced,and 4599509 SNPs and 846654 InDels were generated,among which 196124 SNPs were nonsynonymous and 9690 InDels were *** on the Indels,genome-wide marker primers were designed,and 3219 of 40366 primer pairs were selected to construct the core InDel marker *** molecular ID of 104 sweetpotato samples verified the availability of these *** sweetpotato population structures were then assessed through multiple approaches using SNPs,and diverse approaches demonstrated that population stratification was not obvious for most Chinese germplasm *** many as 20 important agronomic traits were evaluated,and a genome-wide association study was conducted on these traits.A total of 19 high-confidence loci were detected in both *** loci included several candidate genes,such as IbMYB1,IbZEP1,and IbYABBY1,which might be involved in anthocyanin metabolism,carotenoid metabolism,and leaf morphogenesis,*** them,IbZEP1 and IbYABBY1 were first reported in *** variants in the promoter and the expression levels of IbZEP1 were significantly correlated with f lesh color(orange or not orange)in *** expression levels of IbYABBY1 were also correlated with leaf *** results will assist in genetic and breeding studies in sweetpotato.

关键词： germplasm breeding traits