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Throughput Maximization for Multi-UAV Enabled Millimeter Wave WPCN: Joint Time and Power Allocation

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China Communications 2020年第10期17卷 142-156页

作者： jiansong miao Pengjie Wang Qian Zhang Yue Wang School of Information and Communication Engineering Beijing University of Posts and TelecommunicationsBeijing 100876China Beijing Laboratory of Advanced Information Network Beijing University of Posts and TelecommunicationsBeijing 100876China

In this paper,we investigate the effective deployment of millimeter wave(mmWave)in unmanned aerial vehicle(UAV)-enabled wireless powered communication network(WPCN).In particular,a novel framework for optimizing the performance of such UAV-enabled WPCN in terms of system throughput is *** the considered model,multiple UAVs monitor in the air along the scheduled flight trajectory and transmit monitoring data to micro base stations(mBSs)with the harvested energy via *** this case,we propose an algorithm for jointly optimizing transmit power and energy transfer *** solve the non-convex optimization problem with tightly coupled variables,we decouple the problem into more tractable *** leveraging successive convex approximation(SCA)and block coordinate descent techniques,the optimal solution is obtained by designing a two-stage joint iteration optimization *** results show that the proposed algorithm with joint transmit power and energy transfer time optimization achieves signiﬁcant performance gains over Q-learning method and other benchmark schemes.

关键词： millimeter-wave(mmWave) unmanned aerial vehicle(UAV) wireless powered communication network energy supply joint optimization

A comparative study on polypropylene separators coated with different inorganic materials for lithium-ion batteries

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Frontiers of Chemical Science and Engineering 2017年第3期11卷 346-352页

作者： Linghui Yu jiansong miao Yi Jin Jerry Y.S. Lin School for Engineering of Matter Transport and Energy Arizona State University Tempe AZ 85287 USA State Key Laboratory of Operation and Control of Renewable Energy & Storage Systems China Electric Power Research Institute Beijing 100192 China

Coating commercial porous polyolefin separators with inorganic materials can improve the thermal stability of the polyolefin separators and hence improve the safety of lithium-ion batteries. Several different inorganic materials have been studied for the coating. However, there lacks a study on how different the properties of separators, in inorganic materials affect terms of thermal stability and cell performance. Herein, we present such a study on coating a commercial polypropylene separator with four inorganic materials, i.e., Al2O3, SiO2, ZrO2 and zeolite. All inorganic coatings have improved thermal stability of the separators although with differences. The coating layers add 28%-45% of electrical resistance compared with the pure polypropylene separator, but all the cells prepared with the coated polypropylene separators have the same electrical chemical performance as the uncoated separator in terms of rate capability and capacities at different temperatures.

关键词： lithium-ion battery battery safety composite separator porosity tortuosity

Secrecy energy efficiency maximization for UAV-enabled multi-hop mobile relay system

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The Journal of China Universities of Posts and Telecommunications 2022年第3期29卷 81-91页

作者： miao jiansong Li Hairui Zheng Ziyuan Wang Chu Zhao Zhenmin Beijing Laboratory of Advanced Information Networks Beijing University of Posts and TelecommunicationsBeijing 100876China

To deal with the secrecy issues and energy efficiency issues in the unmanned aerial vehicles(UAVs) assisted communication systems, an UAV-enabled multi-hop mobile relay system is studied in an urban environment. Multiple rotary-wing UAVs with energy budget considerations are employed as relays to forward confidential information between two ground nodes in the presence of multiple passive eavesdroppers. The system secrecy energy efficiency(SEE), defined by the ratio of minimum achievable secrecy rate(SR) to total propulsion energy consumption(PEC), is maximized via jointly optimizing the trajectory and transmit power of each UAV relay. To solve the formulated non-convex fractional optimization problem subject to mobility, transmit power and information-causality constraints, an effective iterative algorithm is proposed by applying the updated-rate-assisted block coordinate decent method, successive convex approximation(SCA) technique and Dinkelbach method. Simulation results demonstrate the effectiveness of the proposed joint trajectory design and power control scheme.

关键词： secrecy transmission unmanned aerial vehicle(UAV) trajectory optimization mobile relay

The optimal power distribution in cooperative communication relay system

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High Technology Letters 2013年第4期19卷 371-377页

作者：张超一 Wu Muqing miao jiansong Luan Linlin Laboratory of Network System Architecture and Convergence Beijing University of Post and Telecommunications College of Technology Beijing Forestry University

In order to optimize power utilization of relay nodes in cooperative communication,a power allocation algorithm with objective function to maximize system capacity is *** on the convex optimization theory,an ellipsoid algorithm is used to solve this problem,which could simplify the subgradient choosing steps and improve convergence stability,so that an optimized power allocation algorithm is *** analysis and simulation results show that the algorithm can effectively distribute the power of each node with lower complexity,and ensure the transmission capability of relay nodes in cooperative communication.

关键词： relay network power distribution convex optimization ellipsoid algorithm

天冬酰胺功能化螯合纤维素的制备表征及对重金属的吸附去除

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高分子材料科学与工程 2023年第1期39卷 57-63,69页

作者：苗健崧丁保宏尤楠辽宁石油化工大学石油化工学院辽宁抚顺113001

纤维素是一种储量丰富、可持续、环境友好的优质天然材料。文中为了改善纤维素对重金属的吸附去除能力,利用天冬酰胺作为改性剂,通过Schiff碱反应,制备了天冬酰胺功能化的螯合纤维素(Asn-CL),表征了其形貌和结构,研究了其对水溶液中Cd^(... 详细信息

纤维素是一种储量丰富、可持续、环境友好的优质天然材料。文中为了改善纤维素对重金属的吸附去除能力,利用天冬酰胺作为改性剂,通过Schiff碱反应,制备了天冬酰胺功能化的螯合纤维素(Asn-CL),表征了其形貌和结构,研究了其对水溶液中Cd^(2+)和Pb^(2+)的吸附去除性能。Asn-CL吸附Cd^(2+)和Pb^(2+)的最佳pH范围为4.5~5.5;在30 min内,Asn-CL对Cd^(2+)和Pb^(2+)的吸附能快速地达到平衡;在30℃时,Asn-CL对Cd^(2+)和Pb^(2+)的吸附容量分别为126.2 mg/g和172.1 mg/g,与微晶纤维素相比,Asn-CL能够明显地增强对Cd^(2+)和Pb^(2+)的吸附去除能力。Langmuir和准二级动力学模型可以很好地描述Asn-CL对2种金属离子的吸附过程。Asn-CL具有较好的可再生性,能够重复使用。

关键词：螯合纤维素重金属吸附去除希夫碱

Potential risks of organic contaminated soil after persulfate remediation:Harmful gaseous sulfur release

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Journal of Environmental Sciences 2024年第1期135卷 1-9页

作者： Yuyang Long Zixiao Wu Xiaodong Ding jiansong Chen Dongsheng Shen Jiali Shentu Cai Hui Zhejiang Provincial Key Laboratory of Solid Waste Treatment and Recycling Zhejiang Engineering Research Center of Non-ferrous Metal Waste RecyclingInstrumental Analysis CenterSchool of Environmental Science and EngineeringZhejiang Gongshang UniversityHangzhou 310012China Shangyu Yingtai Fine Chemical Co. Ltd.Shaoxing 312000China Hangzhou Ecological Environment Monitoring Center Hangzhou 310007China

Persulfate is considered a convenient and efficient remediation agent for organic contaminated ***,the potential risk of sulfur into the soil remediation by persulfate remains *** this study,glass bottles with different persulfate dosages and groundwater tables were set up to simulate persulfate remediation of organic pollutants(aniline).The results found sulfate to be the main end-product(83.0%–99.5%)of persulfate remediation after10 ***,H_(2)S accounted for 93.4%–99.4%of sulfur reduction end-products,suggesting that H_(2)S was the final fate of sulfur.H_(2)S was released rapidly after one to three days at a maximum concentration of 33.0 ppm,which is sufficient to make a person *** to the fitted curve results,H_(2)S concentration decreased to a safe concentration(0.15 ppm)after 20–85 ***,the maximum concentration of methanethiol reached 0.6 *** results indicated that secondary pollution from persulfate remediation could release harmful gases over a long ***,persulfate should be used more carefully as a remediation agent for soil contamination.

关键词： Gaseous sulfur release H_2S Long period potential risk Organic contaminated soil remediation Persulfate

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战术弹道导弹打击航母的末制导精度研究

弹箭与制导学报 2008年第5期28卷 1-4页

作者：张宏苗建松祁载康刘雄飞北京理工大学宇航科学技术学院北京100081 驻247厂军事代表室太原030051

将比例导引作为战术弹道导弹末制导律。假设航母随机阶跃机动,采用伴随法和无量纲化法研究其末制导精度。分析结果表明,尽管脱靶量均方根值与航母机动能力成正比,且制导系统动力学阶数和有效导航比对脱靶量影响较大,但是对于打击机动能... 详细信息

将比例导引作为战术弹道导弹末制导律。假设航母随机阶跃机动,采用伴随法和无量纲化法研究其末制导精度。分析结果表明,尽管脱靶量均方根值与航母机动能力成正比,且制导系统动力学阶数和有效导航比对脱靶量影响较大,但是对于打击机动能力有限的航母来说,其制导精度很高。最后指出战术弹道导弹精确制导化需解决的相关技术。

关键词：战术弹道导弹航空母舰脱靶量伴随法

Monolithic integrated optoelectronic chip for vector force detection

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Microsystems & Nanoengineering 2024年第3期10卷 245-257页

作者： jiansong Feng Zhongqi Wang Mengyuan Zhanghu Xu Zhang Yong Shen Jing Yang Zhibin Li Bin Chen Taihong Wang Xiaolong Chen Zhaojun Liu Department of Electrical and Electronic Engineering Southern University of Science and TechnologyShenzhen 518055China Department of Electrical and Electronic Engineering The University of Hong KongHong KongChina

Sensors with a small footprint and real-time detection capabilities are crucial in robotic surgery and smart wearable *** device footprint while maintaining its high performance is a major challenge and a significant limitation to their ***,we proposed a monolithic integrated micro-scale sensor,which can be used for vector force *** sensor combines an optical source,four photodetectors,and a hemispherical silicone elastomer component on the same sapphire-based AlGaInP *** chip-scale optical coupling is achieved by employing the laser lift-off techniques and the flip-chip bonding to a processed sapphire *** hemispherical structure device can detect normal and shear forces as low as 1mN within a measurement range of 0–220 mN for normal force and 0–15 mN for shear *** packaging,the sensor is capable of detecting forces over a broader range,with measurement capabilities extending up to 10 N for normal forces and 0.2 N for shear *** has an accuracy of detecting a minimum normal force of 25 mN and a minimum shear force of 20 ***,this sensor has been validated to have a compact footprint of approximately 1.5 mm^(2),while maintaining high real-time *** also demonstrate its promising potential by combining this sensor with fine surface texture perception in the fields of compact medical robot interaction and wearable devices.

关键词： robot force smart

Full T-cell activation and function in teleosts require collaboration of first and co-stimulatory signals

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Zoological Research 2024年第1期45卷 13-24页

作者： Wei Liang Kang Li Haiyou Gao Kunming Li jiansong Zhang Qian Zhang Xinying Jiao Jialong Yang Xiumei Wei State Key Laboratory of Estuarine and Coastal Research School of Life SciencesEast China Normal UniversityShanghai 200241China Laboratory for Marine Biology and Biotechnology Qingdao National Laboratory for Marine Science and TechnologyQingdaoShandong 266237China

Mammalian T-cell responses require synergism between the first signal and co-stimulatory ***,whether and how dual signaling regulates the T-cell response in early vertebrates remains *** the present study,we discovered that the Nile tilapia(Oreochromis niloticus)encodes key components of the LAT signalosome,namely,LAT,ITK,GRB2,VAV1,SLP-76,GADS,and PLC-γ*** components are evolutionarily conserved,and CD3εmAb-induced T-cell activation markedly increased their ***,at least ITK,GRB2,and VAV1 were found to interact with LAT for signalosome *** of the first signal,the NF-κB,MAPK/ERK,and PI3K-AKT pathways were activated upon CD3εmAb ***,treatment of lymphocytes with CD28 mAbs triggered the AKT-mTORC1 pathway downstream of the co-stimulatory *** CD3εand CD28 mAb stimulation enhanced ERK1/2 and S6 phosphorylation and elevated NFAT1,c-Fos,IL-2,CD122,and CD44 expression,thereby signifying T-cell ***,rather than relying on the first or co-stimulatory signal alone,both signals were required for T-cell *** T-cell activation was accompanied by marked apoptosis and cytotoxic *** findings suggest that tilapia relies on dual signaling to maintain an optimal T-cell response,providing a novel perspective for understanding the evolution of the adaptive immune system.

关键词： Oreochromis niloticus CD3 CD28 T cells Adaptive immunity Evolution