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Correlation equalizer and its simulation for underwater acoustic channels

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Chinese Journal of Acoustics 1999年第4期18卷 360-369页

作者： ai yuhui HUI Junyping(Underwater Acoustic Engineering Dept., Harbin Engineering University Harbin 150001)

A robust correlation equalizer is presented to resolve the equalization divergence,which is caused by the distribution of channel response function's zero points outside the unit circle. The equalizer is robust except that the channel response function has zero points just on the wht circle. Noncausal two-side prediction is also proposed. Based on the prediction and FFT the transversal form of the correlation equdrier and the fast algorithIn are developed. The simulation results of the correlation equallzer of transversal form are given.

关键词： Correlation equalizer and its simulation for underwater acoustic channels IEEE

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UMFSK水声通信技术研究

应用声学 2001年第1期20卷 15-22页

作者：艾宇慧岳沛周瑜丽惠俊英哈尔滨工程大学水声研究所哈尔滨150001

在ＭＦＳＫ基础上，本文提出了ＵＭＦＳＫ信道编码方法．采用了窄带调频和跳频调制技术，故在一定程度上抑制了由多途效应引起的码内／码间干扰；提出了基于ＵＭＦＳＫ的实时信道标校技术，可对信道进行稳健均衡，抗信道多途引起的码... 详细信息

在ＭＦＳＫ基础上，本文提出了ＵＭＦＳＫ信道编码方法．采用了窄带调频和跳频调制技术，故在一定程度上抑制了由多途效应引起的码内／码间干扰；提出了基于ＵＭＦＳＫ的实时信道标校技术，可对信道进行稳健均衡，抗信道多途引起的码内干扰，进行了湖试，取得了试验数据并进行了数据分析．分析表明：ＵＭＦＳＫ可抑制码元相消干涉引起的码内干扰，其效果随码元调频带宽的增大而变好；信道标校技术可对信道进行稳健均衡，并由于结构简单，可做到实时实现．基于ＵＭＦＳＫ的误码率为１０－３（通信带宽２ｋＨｚ，速率１００－１５０ｂｐｓ）．

关键词： MFSK 水声通信信道均衡 UMFSK 信道编码解码原理

FK506 contributes to peripheral nerve regeneration by inhibiting neuroinflammatory responses and promoting neuron survival

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Neural Regeneration Research 2025年第7期20卷 2108-2115页

作者： yuhui Kou Zongxue Jin Yusong Yuan Bo Ma Wenyong Xie Na Han Department of Trauma and Orthopedics Peking University People’s HospitalBeijingChina National Center for Trauma Medicine Peking University People’s HospitalBeijingChina Key Laboratory of Trauma and Neural Regeneration(Peking University) Ministry of EducationBeijingChina Trauma Medicine Center Peking University People’s HospitalBeijingChina Department of Orthopedics China-Japan Friendship HospitalBeijingChina

FK506(Tacrolimus)is a systemic immunosuppressant approved by the *** and Drug ***506 has been shown to promote peripheral nerve regeneration,however,its precise mechanism of action and its pathways remain *** this study,we established a rat model of sciatic nerve injury and found that FK506 improved the morphology of the injured sciatic nerve,increased the numbers of motor and sensory neurons,reduced inflammatory responses,markedly improved the conduction function of the injured nerve,and promoted motor function *** findings suggest that FK506 promotes peripheral nerve structure recovery and functional regeneration by reducing the intensity of inflammation after neuronal injury and increasing the number of surviving neurons.

关键词： FK506 inflammation motor neurons nerve regeneration neuron peripheral nerve injury sensory neurons

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基于VSG的微电网逆变器控制策略研究

宁夏电力 2016年第5期 1-5页

作者：黎金英邓玉辉艾欣绥和工业学院电气与电子工程学院越南绥和56000 广宁工业大学电气与电子工程学院越南广宁20000 华北电力大学新能源电力系统国家重点实验室北京102206

针对微电网中的分布式电源出力的间歇性导致微电网功率不稳定的问题,基于虚拟同步发电机(Virtual Synchronous Generator,VSG)技术的控制方法,建立VSG的数学模型,设计了一种基于电流、电压和功率控制的反馈控制器,提出了一种全新的VSG... 详细信息

针对微电网中的分布式电源出力的间歇性导致微电网功率不稳定的问题,基于虚拟同步发电机(Virtual Synchronous Generator,VSG)技术的控制方法,建立VSG的数学模型,设计了一种基于电流、电压和功率控制的反馈控制器,提出了一种全新的VSG控制策略,实现分布式电源动态特性对微电网中有功功率和无功功率的均分控制。并通过Matlab/Simulink仿真,验证了所提控制算法的有效性。结果表明:该控制策略对抑制因新能源发电并网导致的电网波动、提高电能质量具有重要意义。

关键词：虚拟同步发电机微电网有功功率无功功率控制策略

Designing Electronic Structures of Multiscale Helical Converters for Tailored Ultrabroad Electromagnetic Absorption

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Nano-Micro Letters 2025年第1期17卷 439-455页

作者： Zhaobo Feng Chongbo Liu Xin Li Guangsheng Luo Naixin Zhai Ruizhe Hu Jing Lin Jinbin Peng yuhui Peng Renchao Che Key Laboratory of Jiangxi Province for Persistent Pollutants Control and Resources Recycle School of Environmental and Chemical EngineeringNanchang Hangkong UniversityNanchang 330063People’s Republic of China School of Physics and Materials Nanchang UniversityNanchang 330031People’s Republic of China Key Laboratory of Nondestructive Testing Ministry of EducationNanchang Hangkong UniversityNanchang 330063People’s Republic of China Laboratory of Advanced Materials Shanghai Key Lab of Molecular Catalysis and Innovative MaterialsAcademy for Engineering and TechnologyFudan UniversityShanghai 200438People’s Republic of China

Atomic-scale doping strategies and structure design play pivotal roles in tailoring the electronic structure and physicochemical property of electromagnetic wave absorption(EMWA)***,the relationship between configuration and electromagnetic(EM)loss mechanism has remained ***,drawing inspiration from the DNA transcription process,we report the successful synthesis of novel in situ Mn/N co-doped helical carbon nanotubes with ultrabroad EMWA *** calculation and EM simulation confirm that the orbital coupling and spin polarization of the Mn–N4–C configuration,along with cross polarization generated by the helical structure,endow the helical converters with enhanced EM *** a result,HMC-8 demonstrates outstanding EMWA performance,achieving a minimum reflection loss of−63.13 dB at an ultralow thickness of 1.29 *** precise tuning of the graphite domain size,HMC-7 achieves an effective absorption bandwidth(EAB)of 6.08 GHz at 2.02 mm ***,constructing macroscale gradient metamaterials enables an ultrabroadband EAB of 12.16 GHz at a thickness of only 5.00 mm,with the maximum radar cross section reduction value reaching 36.4 dB *** innovative approach not only advances the understanding of metal–nonmetal co-doping but also realizes broadband EMWA,thus contributing to the development of EMWA mechanisms and applications.

关键词： Metal-nonmetal co-doping 3d-2p orbital coupling Spin polarization Helical structure Broadband EM wave absorption

Moments of first hitting times for bitth-death processes on trees

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Frontiers of Mathematics in China 2019年第4期14卷 833-854页

作者： yuhui ZHANG School of Mathematical Sciences Beijing Normal University Laboratory of Mathematics and Complex Systems Ministry of Education Beijing 100875 China

An explicit and recursive representation is presented for moments of the first hitting times of birth-death processes on trees. Based on that, the criteria on ergodicity, strong ergodicity, and l-ergodicity of the pro... 详细信息

关键词： Eirth-death process on trees ergodicity hitting time returning time

Criteria on ergodicity and strong ergodicity of single death processes

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Frontiers of Mathematics in China 2018年第5期13卷 1215-1243页

作者： yuhui ZHANG School of Mathematical Sciences Beijing Normal University Laboratory of Mathematicsand Complex Systems Ministry of Education Beijing 100875 China

Based on an explicit representation of moments of hitting times for single death processes, the criteria on ergodicity and strong ergodicity are obtained. These results can be applied for an extended class of branching processes. Meanwhile, some sufficient and necessary conditions for recurrence and exponential ergodicity as well as extinction probability for the processes are presented.

关键词： Single death process ergodicity strong ergodicity recurrence moments of hitting times

Property analysis of logic Petri nets by marking reachability graphs

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Frontiers of Computer Science 2014年第4期8卷 684-692页

作者： Yuyue DU yuhui NING College of Information Science and Engineering Shandong University of Science and Technology Qingdao 266590 China

Logic Petri nets （LPNs） are suitable to describe and analyze batch processing functions and passing value indeterminacy in cooperative systems. To investigate the dynamic properties of LPNs directly, a new method for analyzing LPNs is proposed based on marking reachability graphs in this paper. Enabled conditions of transitions are obtained and a marking reachability graph is constructed. All reach- able markings can be obtained based on the graph; the fairness and reversibility of LPNs are analyzed. Moreover, the computing complexity of the enabled conditions and reachable markings can be reduced by this method. The advantages of the proposed method are illustrated by examples and analysis.

关键词： logic Petri nets enabled condition reachable marking graph fairness reversibility

Allocating workload to minimize the power consumption of data centers

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Frontiers of Computer Science 2017年第1期11卷 105-118页

作者： Ruihong LIN yuhui DENG Department of Computer Science Jinan University Guangzhou 510632 China

Reducing the power consumption has become one of the most important challenges in designing modem data centers due to the explosive growth of data. The tradi- tional approaches employed to decrease the power consump- tion normally do not consider the power of IT devices and the power of cooling system simultaneously. In contrast to existing works, this paper proposes a power model which can minimize the overall power consumption of data centers by balancing the computing power and cooling power. Fur- thermore, an enhanced genetic algorithm （EGA） is designed to explore the solution space of the power model since the model is a liner programming problem. However, EGA is computing intensive and the performance gradually decreases with the growth of the problem size. Therefore, heuristic greedy sequence （HGS） is proposed to simplify the calcu- lation by leveraging the nature of greed. In contrast to EGA, HGS can determine the workload allocation of a specific data center layout with only one calculation. Experimental results demonstrate that both the EGA and HGS can significantly reduce the power consumption of data centers in contrast to the random algorithm. Additionally, HGS significantly out- performs EGA in terms of the continuity of workload alloca- tion and execution performance.

关键词： data center energy conservation workload allocation power model