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故宫博物院院刊 2024年第8期 20-35,155页

作者：杨怡菲徐怡涛北京大学考古文博学院

本文运用建筑考古形制类型学研究方法,对北京地区辽代至明代多层砖石塔进行了建筑形制分期研究,并在此基础上,对北京地区砖石塔建造过程中的“模仿”、重修问题以及年代存疑的个案进行深入探讨。

关键词：砖石塔仿木构北京建筑考古

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川渝地区南宋石室墓仿木构建筑史料研究

文物季刊 2024年第1期 122-138页

作者：黄青岩徐怡涛北京大学考古文博学院北京大学中国考古学研究中心

川渝地区位于我国西南部,具有较为封闭的地理环境以及长期具有明显地方传统的历史文化。根据目前考古发现可知,川渝地区出土了较大数量的宋代墓葬,其中盆地周边丘陵山地多出土石室墓,石室墓中常见较为精美的仿木构雕刻,仿木构的形制亦... 详细信息

川渝地区位于我国西南部,具有较为封闭的地理环境以及长期具有明显地方传统的历史文化。根据目前考古发现可知,川渝地区出土了较大数量的宋代墓葬,其中盆地周边丘陵山地多出土石室墓,石室墓中常见较为精美的仿木构雕刻,仿木构的形制亦呈现出一定的变化。通过对重庆及四川地区仿木构石室墓的形制进行排比分期,研究其发展趋势及流变现象,将其具体分为乾道及之前(1173之前)、淳熙年间(1174-1189)、绍熙至嘉定(1190-1224)、嘉定之后(1224之后)四期,其中第三期又以庆元(1195-1200)分为前后两个部分;并在上述年代学研究的基础上,解决川渝地区仿木构石室墓的形制断代问题。此外,通过对比研究,探讨当时同地域地面木构及仿木构建筑特点及形制发展的异同,补充川渝地区宋代建筑的研究材料,阐释川渝地区仿木构石室墓在建筑历史研究中的重要价值。

关键词：川渝南宋石室墓仿木构建筑形制分期

Topology tracking of dynamic UAV wireless networks

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Chinese Journal of Aeronautics 2022年第11期35卷 322-335页

作者： Yehui SONG Guoru DING Jiachen SUN Jinghua LI yitao xu College of Communications Engineering Army Engineering University of PLANanjing 210007China

Wireless network is the communication foundation that supports the intelligentization of Unmanned Aerial Vehicle(UAV) swarm. The topology of UAV communication network is the key to understanding and analyzing the behavior of UAV swarm, thus supporting the further prediction of UAV operations. However, the UAV swarm network topology varies over time due to the high mobility and diversified mission requirements of UAVs. Therefore, it is important but challenging to research dynamic topology inference for tracking the topology changes of the UAV network,especially in non-cooperative manner. In this paper, we study the problem of inferring UAV swarm network topology based on external observations, and propose a dynamic topology inference method. First, we establish a sensing framework for acquiring the communication behavior of the target network over time. Then, we expand the multi-dimensional dynamic Hawkes process to model the communication event sequence in a dynamic wireless network. Finally, combining the sliding time window mechanism, the maximum weighted likelihood estimation is applied to inferring the network topology. Extensive simulation results demonstrate the effectiveness of the proposed method.

关键词： Dynamic topology inference Event detection Hawkes process UAV swarm Wireless networks

Specific Emitter Identification for IoT Devices Based on Deep Residual Shrinkage Networks

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China Communications 2021年第12期18卷 81-93页

作者： Peng Tang yitao xu Guofeng Wei Yang Yang Chao Yue College of Communications Engineering Army Engineering University of PLANanjing 210007China

Specific emitter identification can distin-guish individual transmitters by analyzing received signals and extracting inherent features of hard-ware *** extraction is a key part of traditional machine learning-based methods,but manual extrac-tion is generally limited by prior professional *** the same time,it has been noted that the per-formance of most specific emitter identification meth-ods degrades in the low signal-to-noise ratio(SNR)*** deep residual shrinkage network(DRSN)is proposed for specific emitter identification,particularly in the low *** soft threshold can preserve more key features for the improvement of performance,and an identity shortcut can speed up the training *** collect signals via the receiver to create a dataset in the actual *** DRSN is trained to automatically extract features and imple-ment the classification of *** results show that DRSN obtains the best accuracy un-der different SNRs and has less running time,which demonstrates the effectiveness of DRSN in identify-ing specific emitters.

关键词： specific emitter identification IoT de-vices deep learning soft threshold deep residual shrinkage networks

Exploring Channel Diversity in HF Communication Systems： A Matching-Potential Game Approach

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China Communications 2018年第9期15卷 60-72页

作者： Wen Li Lang Ruan Yifan xu Yuli Zhang yitao xu Xinhong Shao College of Communications Engineering Army Engineering University of PLA Nanjing 210000 China Science and Technology on Communication Networks Laboratory Shijiazhuang 050000 China

This paper investigates the channel diversity problem in high frequency(HF) communication systems. Due to the limited HF spectrum resources, a HF communication system with shared channels is considered, where each user equipment(UE) has individual communication demand. In order to maximize the communication probability of the whole system, a matching-potential game framework is designed. In detail, the channel diversity problem is decomposed into two sub-problems. One is channel-transmitter matching problem, which can be formulated as a many-to-one matching game. The other is the transmitter allocation problem which decides the transmission object that each transmitter communicates with under channel-transmitter matching result, and this sub-problem can be modeled as a potential game. A multiple round stable matching algorithm(MRSMA) is proposed, which obtains a stable matching result for the first sub-problem, and a distributed BR-based transmitter allocation algorithm(DBRTAA) is designed to reach Nash Equilibrium(NE) of the second sub-problem. Simulation results verify the effectiveness and superiority of the proposed method.

关键词： HF communication channel diversity game theory many-to-one matching game potential game.

Cognitive J^(2)SAC:Joint Jamming,Sensing,and Communication Under Antagonistic Environment

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中国通信:英文版 2023年第9期20卷 78-95页

作者： Jiangchun Gu Guoru Ding Yizhen Yin Haichao Wang yitao xu Yehui Song College of Communications Engineering Army Engineering UniversityNanjing 210007China College of Joint Design and Innovation Xi’an Jiaotong UniversityXi’an 710049China

Integrated sensing and communication(ISAC)is regarded as a recent advanced technology,which is expected to realize the dual functions of sensing and communication simultaneously in one ***,it still faces the challenges of the information security and transmission robustness caused by the openness of wireless channel,especially under antagonistic ***,this article develops a generalized framework,named cognitive joint jamming,sensing and communication(cognitive J2SAC),to empower the current sensing/communication/jamming system with a“brain”for realizing precise sensing,reliable communication and effective jamming under antagonistic *** kinds of gains can be captured by cognitive J2SAC,including integrated gain,cooperative gain and cognitive ***,we highlight the enabling mechanism among jamming,sensing,and communication,as well as illustrating several typical use cases of cognitive ***,several key enabled technologies are analyzed and a typical sensing enhance integrated communication and jamming case study is discussed to verify the effectiveness of the proposed *** but not the least,the future directions are listed before concluding this *** sensing and communication(ISAC)is regarded as a recent advanced technology,which is expected to realize the dual functions of sensing and communication simultaneously in one ***,it still faces the challenges of the information security and transmission robustness caused by the openness of wireless channel,especially under antagonistic ***,this article develops a generalized framework,named cognitive joint jamming,sensing and communication(cognitive J2SAC),to empower the current sensing/communication/jamming system with a“brain”for realizing precise sensing,reliable communication and effective jamming under antagonistic *** kinds of gains can be captured by cognitive J2SAC,including integrated gain

关键词： integrated sensing and communication(ISAC) information security joint jamming,sensing and communication(J2SAC) cognition theory

Photoreduction of CO_2 to methanol over Bi_2S_3/CdS photocatalyst under visible light irradiation

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Journal of Natural Gas Chemistry 2011年第4期20卷 413-417页

作者： Xin Li Juntao Chen Huiling Li Jingtian Li yitao xu Yingju Liu Jiarong Zhou The Guangdong Provincial Laboratory of Green Chemical Technology School of Chemistry and Chemical EngineeringSouth China University of Technology Guangzhou 510641 Guangdong China Institute of Biomaterial College of ScienceSouth China Agricultural University Guangzhou 510642 Guangdong China

The Bi2S3,CdS and Bi2S3/CdS photocatalysts were prepared by direct reactions between their corresponding salt and thiourea in a hy- drothermal *** photocatalytic activities of these photocatalysts for reducing CO2 to CH3OH under visible light irradiation have been *** results show that the photocatalytic activity and visible light response of Bi2S3 are higher than those of *** Bi2S3 modification can enhance the photocatalytic activity and visible light response of *** photocatalytic activity of Bi2S3/CdS hetero-junction photocatalyst was the highest and the highest yields of methanol was 613μmol/g when the weight proportion of Bi2S3 to CdS was 15%,which was about three times as large as that of CdS or two times of that of Bi2S3.

关键词： photocatalytic reduction carbon dioxide heterogeneous catalysts CdS Bi2S3 CO2 reduction

Energy-Efficient Multi-UAV Coverage Deployment in UAV Networks:A Game-Theoretic Framework

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China Communications 2018年第10期15卷 194-209页

作者： Lang Ruan Jinlong Wang Jin Chen yitao xu Yang Yang Han Jiang Yuli Zhang Yuhua xu College of Communications Engineering Army Engineering University of PLA Key Embedded Technology and Intelligent System Laboratory College of Information Science and Engineering Guilin University of Technology

UAV cooperative control has been applied in many complex UAV communication networks. It remains challenging to develop UAV cooperative coverage and UAV energy-efficient communication technology. In this paper, we investigate current works about UAV coverage problem and propose a multi-UAV coverage model based on energy-efficient communication. The proposed model is decomposed into two steps: coverage maximization and power control, both are proved to be exact potential games(EPG) and have Nash equilibrium(NE) points. Then the multi-UAV energy-efficient coverage deployment algorithm based on spatial adaptive play(MUECD-SAP) is adopted to perform coverage maximization and power control, which guarantees optimal energy-efficient coverage deployment. Finally, simulation results show the effectiveness of our proposed approach, and confirm the reliability of proposed model.

关键词： UAV networks multi-UAV coverage energy-efficient potential games Nash equilibrium

Proactive optimization of transmission power and 3D trajectory in UAV-assisted relay systems with mobile ground users

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Chinese Journal of Aeronautics 2021年第5期34卷 129-144页

作者： Jiangchun GU Guoru DING yitao xu Haichao WANG Qihui WU School of Communications Engineering Army Engineering University of PLANanjing 210007China School of Electronic and Information Engineering Nanjing University of Aeronautics and AstronauticsNanjing 210016China

In this paper,an Unmanned Aerial Vehicle(UAV)-assisted relay communication system is studied,where a UAV is served as a flying relay to maintain a communication link between a mobile source node and a remote destination ***,an average outage probability minimization problem is formulated firstly,with the constraints on the transmission power of the source node,the maximum energy consumption budget,the transmission power,the speed and acceleration of the flying UAV ***,the closed-form of outage probability is derived,under the hybrid line-of-sight and non-line-of-sight probability channel *** deal with the formulated nonconvex optimization,a long-term proactive optimization mechanism is *** particular,firstly,an approximation for line-of-sight probability and a reformulation of the primal problem are given,***,the reformulated problem is transformed into two subproblems:one is the transmission power optimization with given UAV’s trajectory and the other is the trajectory optimization with given transmission power ***,two subproblems are tackled via tailoring primal–dual subgradient method and successive convex approximation,***,a proactive optimization algorithm is proposed to jointly optimize the transmission power allocation and the three-dimensional ***,simulation results demonstrate the performance of the proposed algorithm under various parameter configurations.

关键词： Outage probability Primal-dual subgradient Proactive optimization Successive convex approximation Unmanned Aerial Vehicle(UAV)relay

宋金时期“下卷昂”的形制演变与时空流布研究

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文物 2017年第2期 89-96+1页

作者：徐怡涛北京大学考古文博学院

按《营造法式》定义,昂分为上昂、下昂两类,下昂又可分为琴面、批竹两种亚型。本文从北方地区现存的建筑史料中,选取了一种不同于批竹昂、琴面昂的"下卷昂",以建筑考古类型学的方法,对这一非主流下昂形制的时空问题进行了初步探讨,认为... 详细信息

按《营造法式》定义,昂分为上昂、下昂两类,下昂又可分为琴面、批竹两种亚型。本文从北方地区现存的建筑史料中,选取了一种不同于批竹昂、琴面昂的"下卷昂",以建筑考古类型学的方法,对这一非主流下昂形制的时空问题进行了初步探讨,认为下卷昂最大可能首现于中晚唐前后的今陕西西安地区,继而沿交通线向周边地区扩散,但其流传仅以两京和陕西周边地区为主,未能影响到河北、山东、山西北部等地。下卷昂形制在宋金两朝形制的变化主要体现在华头子、昂嘴及其与其他斗拱构件的共存关系上,其中,晋西南地区是目前已知宋金时期下卷昂形制变化最显著的地区。

关键词：下昂万荣稷王庙大殿木构建筑宋金时期