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Error propagation determined iterative channel estimation with ICI mitigation for fast time-varying OFDM channels

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High Technology Letters 2014年第4期20卷 415-420页

作者：张杰 Yang Ruizhe Si Pengbo zhang yanhua Yu Richard College of Electronics Information and Control Engineering Beijing University of Technology Department of Systems and Computer Engineering Carleton University

The intersubcarrier interference(ICI) degrades the performance of the pilot-aided channel estimation in fast time-varying orthogonal frequency division multiplexing(OFDM) *** solve the error propagation in joint channel estimation and data detection due to this ICI,a scheme of error propagation determined iterative estimation is proposed,where in the first iteration,Kalman filter based on signal to interference and noise is designed with ICI transformed to be part of the noise,and for the later iterations,a determined iterative estimation algorithm obtains an optimal output from all iterations using the iterative updating *** results present the significant improvement in the performance of the proposed scheme in high-mobility situation in comparison with the existing ones.

关键词： orthogonal frequency division multiplexing (OFDM) channel estimation intersubcarrier interference (ICI) error propagation Kalman

Airport gate assignment problem with deep reinforcement learning

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High Technology Letters 2020年第1期26卷 102-107页

作者： Zhao Jiaming Wu Wenjun Liu Zhiming Han Changhao zhang Xuanyi zhang yanhua Faculty of Information Technology Beijing University of TechnologyBeijing 100124P.R.China IT Department Beijing Capital International Airport Co.LtdBeijing 100124P.R.China

With the rapid development of air transportation in recent years,airport operations have attracted a lot of *** them,airport gate assignment problem(AGAP)has become a research ***,the real-time AGAP algorithm is still an open *** this study,a deep reinforcement learning based AGAP(DRL-AGAP)is *** optimization object is to maximize the rate of flights assigned to fixed *** real-time AGAP is modeled as a Markov decision process(MDP).The state space,action space,value and rewards have been *** DRL-AGAP algorithm is evaluated via simulation and it is compared with the flight pre-assignment results of the optimization software Gurobiand *** results show that the performance of the proposed DRL-AGAP algorithm is close to that of pre-assignment obtained by the Gurobi optimization ***,the real-time assignment ability is ensured by the proposed DRL-AGAP algorithm due to the dynamic modeling and lower complexity.

关键词： airport gate assignment problem(AGAP) deep reinforcement learning(DRL) Markov decision process(MDP)

Synthesis and Acetylcholinesterase Inhibitory Activity of Polymethoxyflavone Mannich Base Derivatives

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Chemical Research in Chinese Universities 2017年第4期33卷 594-597页

作者： SHI Ling zhang yanhua WANG Caifang LIU Haoran WANG Qiuan College of Chemistry and Chemical Engineering Hunan University Changsha 410082 P. R. China

A series of novel polymethoxyflavone Marmich base derivatives 1--8 was synthesized by Mannich reaction of 5-hydroxy-3,7,3＇,4＇-tetramethoxyflavone 9 with various secondary aliphatic amines and formaldehyde. Their acetylcholmesterase（AChE） inhibitory activities were evaluated. The results showed that most of them exhibited AChE inhibitory activity and especially piperidin-l-yl methyl substituent derivative 5（IC50=0.238 μmol/L） demon- strated stronger activity comparable with the positive control, neoeserinemethyl sulfate（IC50=1.39 μmol/L）, which is worthy of further development as an agent for Alzheimer＇s disease treatment.

关键词： Polymethoxyflavone Mannich base derivative Acetylcholinesterase inhibitory activity

Blockchain and MEC-Assisted Reliable Billing Data Transmission over Electric Vehicular Network:An Actor–Critic RL Approach

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China Communications 2021年第8期18卷 279-296页

作者： Xinyu Ye Meng Li Pengbo Si Ruizhe Yang Enchang Sun yanhua zhang Faculty of Information Technology Beijing University of TechnologyBeijing 100124China Beijing Laboratory of Advanced Information Networks Beijing 100124China

Recently,electric vehicles(EVs)have been widely used under the call of green travel and environmental protection,and diverse requirements for charging are also increasing *** order to ensure the authenticity and privacy of charging information interaction,blockchain technology is proposed and applied in charging station billing ***,there are some issues in blockchain itself,including lower computing efficiency of the nodes and higher energy consumption in the consensus *** handle the above issues,in this paper,combining blockchain and mobile edge computing(MEC),we develop a reliable billing data transmission scheme to improve the computing capacity of nodes and reduce the energy consumption of the consensus *** jointly optimizing the primary and replica nodes offloading decisions,block size and block interval,the transaction throughput of the blockchain system is maximized,as well as the latency and energy consumption of the system are ***,we formulate the joint optimization problem as a Markov decision process(MDP).To tackle the dynamic and continuity of the system state,the reinforcement learning(RL)is introduced to solve the MDP ***,simulation results demonstrate that the performance improvement of the proposed scheme through comparison with other existing schemes.

关键词： electric vehicles billing data interaction blockchain mobile edge computing reinforcement learning

无偿献血招募及血液采集工作中优质献血服务的应用分析

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中国卫生标准管理 2024年第9期15卷 162-166页

作者：朱旭蕊张燕华周淑英青岛市中心血站社会服务部山东青岛266000

目的探讨优质献血服务在无偿献血者招募及血液采集工作中的应用效果。方法选取2021年2月—2022年11月于青岛市中心血站所属献血点无偿捐献全血的献血者中抽取600名为研究对象,依据入组时间不同分为试验组(2022年7—11月献血者,303名)和... 详细信息

目的探讨优质献血服务在无偿献血者招募及血液采集工作中的应用效果。方法选取2021年2月—2022年11月于青岛市中心血站所属献血点无偿捐献全血的献血者中抽取600名为研究对象,依据入组时间不同分为试验组(2022年7—11月献血者,303名)和对照组(2022年2—6月献血者,297名)。对照组献血者接受常规献血服务,试验组献血者接受基于首因效应的优质献血服务。比较2组献血不良反应发生率及严重程度,以自制的问卷调查2组献血者对本次献血服务的满意度以及再献血意愿,统计2组二次献血率。结果试验组献血不良反应率(0.99%)低于对照组(5.05%),差异有统计学意义(P<0.05)。2组献血不良反应以全身表现为主,均为一过性症状,未发生重度献血不良反应。试验组献血者对献血前等待环境、献血中献血环境、献血后休息环境、健康征询、体格检查、采血护理、献血反应处理、等待时间、献血内容告知、服务态度、宣传方式、饮食或纪念品的满意度高于对照组,献血者的个人再献血意愿与动员亲友献血意愿也高于对照组,差异有统计学意义(P<0.05)。试验组二次献血率(34.32%)高于对照组(21.89%),差异有统计学意义(P<0.05)。结论基于首因效应的优质献血服务在无偿献血招募及血液采集工作中的应用可以有效预防和减少献血者的献血不良反应,提高献血者对献血服务的满意度,提升献血者的再献血意愿及二次献血率。

关键词：无偿献血招募血液采集优质献血服务不良反应满意度献血意愿

基于敏感承灾体的雷电灾害风险区划因子优化研究

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气象科学 2024年第4期44卷 716-722页

作者：焦雪李福洪周俊驰张艳华江苏省气象灾害防御技术中心江苏省基础地理信息中心

雷电灾害风险评估和区划是当前全国第一次自然灾害风险普查工作的重要内容。针对试点区县普查中发现的《雷电灾害调查与风险评估技术规范》中指标选取、指标空间精细度等方面存在的值得商榷和改进之处，本文提出以下优化方案：(1)致灾... 详细信息

雷电灾害风险评估和区划是当前全国第一次自然灾害风险普查工作的重要内容。针对试点区县普查中发现的《雷电灾害调查与风险评估技术规范》中指标选取、指标空间精细度等方面存在的值得商榷和改进之处，本文提出以下优化方案：(1)致灾危险性因子选取优化：致灾危险性因子仅使用闪电定位观测数据。(2)承灾体暴露度因子空间尺度精细化：采用1 km×1 km高精度人口和经济数据直接进行栅格计算，而不是采用行政区域均值。(3)承灾体脆弱性因子选取优化：引入了承灾体类型因子，反映出不同承灾体类型的雷电灾害脆弱性和易损性的显著不同；将场所的防雷装置设计审核和按期检测情况作为防雷减灾能力考量指标。同时，本文以常州市金坛区为例，使用该技术方案进行了雷电灾害风险区划并与规范进行对比。结果表明此方案更加科学、合理，反映了评估区域承灾体的雷电灾害风险特征，也更加符合本次普查和评估区划工作精准施策、针对性开展防雷减灾工作的初衷。

关键词：雷电灾害风险区划致灾因子危险性脆弱性精细化

心理咨询与心理疏导对首次献血伴心理障碍者的影响

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中国卫生标准管理 2024年第5期15卷 154-158页

作者：朱旭蕊张燕华周淑英青岛市中心血站社会服务部山东青岛266073

目的探讨心理咨询与心理疏导对首次献血伴心理障碍者的影响。方法选取2022年7月—2023年6月青岛市中心血站接待的278名首次献血伴心理障碍的无偿献血者为研究对象,依据献血时间不同分为试验组(2023年1—6月献血者,141名)与对照组(2022年... 详细信息

目的探讨心理咨询与心理疏导对首次献血伴心理障碍者的影响。方法选取2022年7月—2023年6月青岛市中心血站接待的278名首次献血伴心理障碍的无偿献血者为研究对象,依据献血时间不同分为试验组(2023年1—6月献血者,141名)与对照组(2022年7—12月献血者,137名)。试验组通过心理咨询了解献血者心理障碍的实际情况,据此予以心理疏导。对照组予以献血者常规宣教。统计2组首次献血完成率、献血量以及献血相关不良反应发生率,对于完成献血者,以舒适状况量表(general comfort questionnaire,GCQ)评价献血舒适度,另自行设计调查问卷,对2组献血者献血服务满意度及再献血意愿进行调研。结果试验组献血者首次献血完成率(94.33%)高于对照组(85.40%),差异有统计学意义(P<0.05)。试验组首次献血300 mL者63名(48.23%),首次献血400 mL者38名(27.66%),均多于对照组,差异有统计学意义(P<0.05)。试验组GCQ生理、心理精神、社会文化3个维度与量表总分均高于对照组,差异有统计学意义(P<0.05)。试验组献血者对本组献血服务的态度、主动性、及时性、专业性与整体服务质量满意度均高于对照组,个人再献血意愿度与动员亲友献血意愿度均高于对照组,差异有统计学意义(P<0.05)。结论心理咨询与心理疏导可以帮助改善首次献血者的心理障碍,提高首次献血率与献血量,提升献血者的献血舒适度及对献血服务满意度,对预防献血相关不良反应、提升献血者再献血及动员他人献血意愿具有积极作用。

关键词：无偿献血首次献血心理障碍心理咨询心理疏导舒适度献血意愿

The adaptive distributed learning based on homomorphic encryption and blockchain

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High Technology Letters 2022年第4期28卷 337-344页

作者： YANG Ruizhe ZHAO Xuehui zhang yanhua SI Pengbo TENG Yinglei Faculty of Information Technology Beijing University of TechnologyBeijing 100124P.R.China School of Electronic Engineering Beijing University of Posts and TelecommunicationsBeijing 100876P.R.China

The privacy and security of data are recently research hotspots and *** this issue,an adaptive scheme of distributed learning based on homomorphic encryption and blockchain is ***,in the form of homomorphic encryption,the computing party iteratively aggregates the learning models from distributed participants,so that the privacy of both the data and model is ***,the aggregations are recorded and verified by blockchain,which prevents attacks from malicious nodes and guarantees the reliability of *** these sophisticated privacy and security technologies,the computation cost and energy consumption in both the encrypted learning and consensus reaching are analyzed,based on which a joint optimization of computation resources allocation and adaptive aggregation to minimize loss function is established with the realistic solution ***,the simulations and analysis evaluate the performance of the proposed scheme.

关键词： blockchain distributed machine learning(DML) privacy security

Study on optimal state estimation strategy with dual distributed controllers based on Kalman filtering

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High Technology Letters 2019年第1期25卷 105-110页

作者： Chen Yawen Wang Zhuwei Fang Chao Xu Guangshu zhang yanhua School of Information and Communications Engineering Beijing University of Technology

Considering dual distributed controllers, a design of optimal state estimation strategy is studied for the wireless sensor and actuator network(WSAN). In particular, the optimal linear quadratic(LQ) control strategy with estimated plant state is formulated as a non-cooperative game with network-induced delays. Then, using the Kalman filter approach, an optimal estimation of the plant state is obtained based on the information fusion of the distributed controllers. Finally, an optimal state estimation strategy is derived as a linear function of the current estimated plant state and the last control strategy of multiple controllers. The effectiveness of the proposed closed-loop control strategy is verified by the simulation experiments.

关键词： optimal state estimation strategy wireless sensor and actuator network(WSAN) distributed controllers Kalman filter network-induced delays