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Harnessing overlapped temperature-salinity.gradient in solar-driven interfacial seawater evaporation for efficient steam and electricity.generation

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Journal of Energy.Chemistry 2024年第8期95卷 694-700,I0015页

作者： peida Li Dongtong He Jingchang Sun Jieshan Qiu Zhiy. Wang State Key.Lab of Fine Chemicals Liaoning Key Lab for Energy Materials and Chemical EngineeringDalian University of TechnologyDalian 116024LiaoningChina School of Phy.ics and Electronic Technology Liaoning Normal UniversityDalian 116029LiaoningChina College of Chemical Engineering Beijing University of Chemical TechnologyBeijing 100029China

Solar-driven interfacial water evaporation(SIWE)offers a superb way.to leverage concentrated solar heat to minimize energy.dissipation during seawater *** also engenders overlapped temperaturesalinity.gradient(TSG)between water-air interface and adjacent seawater,affording opportunities of harnessing ***,the efficiency.of conventional SIWE technologies is limited by.significant challenges,including salt passivation to hinder evaporation and difficulties in exploiting overlapped TSG ***,we report self-sustaining hy.rid SIWE for not only.sustainable seawater desalination but also efficient electricity.generation from *** enables spontaneous circulation of salt flux upon seawater evaporation,inducing a self-cleaning evaporative interface without salt passivation for stable steam ***,this design enables spatial separation and simultaneous utilization of overlapped TSG to enhance electricity.*** benefits render a remarkable efficiency.of90.8%in solar energy.utilization,manifesting in co-generation of solar steam at a fast rate of 2.01 kg m^(-2)-h^(-1)and electricity.power of 1.91 W m^(-2)with high *** interfacing the hy.rid SIWE with seawater electroly.er constructs a sy.tem for water-electricity.hy.rogen co-generation without external electricity.*** produces hy.rogen at a rapid rate of 1.29 L h^(-1)m^(-2)and freshwater with 22 times lower Na+concentration than the World Health Organization(WHO)threshold.

关键词： Solar-driven interfacial water evaporation Steam generation Electricity.generation Seawater

基于SM2数字签名的区块链匿名密钥交换协议

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信息安全学报 2024年第3期9卷 19-28页

作者：黄佩达林超伍玮何德彪福建师范大学计算机与网络空间安全学院福州350117 福建师范大学数学与统计学院福州350117 武汉大学国家网络安全学院武汉430072

区块链技术因其去中心化、匿名性、不可篡改、不可伪造等优点,已经成为我国的一项前沿技术,在各领域得到广泛的应用。虽然用户可利用区块链发布匿名交易,有效隐藏交易双方的身份信息,但双方交易完成后传输交易相关数据可能破坏匿名性。... 详细信息

区块链技术因其去中心化、匿名性、不可篡改、不可伪造等优点,已经成为我国的一项前沿技术,在各领域得到广泛的应用。虽然用户可利用区块链发布匿名交易,有效隐藏交易双方的身份信息,但双方交易完成后传输交易相关数据可能破坏匿名性。这是因为在数据传输过程中,为了保证双方通信安全,往往使用认证密钥交换协议认证双方身份,计算会话密钥建立安全信道。由于传统的认证密钥交换协议涉及双方的长期公私钥对信息,所以将泄露交易双方的身份信息。虽然区块链匿名密钥交换可基于交易双方的历史链上交易完成密钥交换,有效保障交易双方的匿名性,但现有区块链匿名密钥交换协议主要基于国外密码算法设计,难以适用于国产区块链平台,不符合我国密码核心技术自主可控的要求。为丰富国产商用密码算法在区块链匿名密钥交换方面的研究,满足区块链交易后双方匿名安全通信的需求,本文以SM2数字签名算法和区块链为基础,构造非交互式和交互式两种区块链匿名密钥交换协议。并在CK安全模型中证明非交互式的协议满足会话密钥安全,交互式的协议满足有前向安全性的会话密钥安全。最后通过理论分析和编程实现结果表明,本文协议在没有比现有协议消耗更多的计算开销与通信代价的前提下,可适用于国产化区块链平台。

关键词：密钥交换协议 SM2数字签名区块链 CK安全模型

Sy.tem construction of a four-side primary.permanent-magnet linear motor drive mechanical press

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Frontiers of Mechanical Engineering 2020年第4期15卷 600-609页

作者： Jintao LIANG Zhengfeng MING peida LI School of Mechano-Electronic Engineering Xidian UniversityXi’an 710071China

A primary.permanent-magnet linear motor (PPMLM) has a robust secondary.structure and high force density.and is appropriate for direct-drive mechanical press. The structure of a four-side PPMLM drive press is presented based on our previous research. The entire press control sy.tem is constructed to realize various flexible forming processes. The control sy.tem scheme is determined in accordance with the mathematical model of PPMLM, and active disturbance rejection control is implemented in the servo controller. Field-circuit coupling simulation is applied to estimate the sy.tem’s performance. Then, a press prototy.e with 6 kN nominal force is fabricated, and the hardware platform of the control sy.tem is constructed for experimental study. Punch strokes with 0.06 m displacement are implemented at trapezoidal speeds of 0.1 and 0.2 m/s;the dy.amic position tracking errors are less than 0.45 and 0.82 mm, respectively. Afterward, continuous reciprocating strokes are performed, and the positioning errors at the bottom dead center are less than 0.015 mm. Complex pulse trajectories are also achieved. The proposed PPMLM drive press exhibits a fast dy.amic response and favorable tracking precision and is suitable for various forming processes.

关键词： mechanical press direct drive primary.permanent-magnet linear motor(PPMLM) servo sy.tem active disturbance rejection control(ADRC) prototy.e experiment

Periodicity.Characteristic of TOAD's Switching Window

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Chinese Journal of Lasers 2000年第2期9卷 161-166页

作者： LIU Xianbing,y. peida (Beijing University.of Posts and Telecommunications, Beijing 100876, China ) 北京邮电大学北京

The periodidity.characteristic of switching window of a terahertz optical asy.metric demultiplexer (TOAD) using numerical simulation was investigated. The results show that the switching window width of TOAD changes periodically.with the time asy.metry.of TOAD and the period is one half of the period of control pulses. The theoretical results agree with the experimental results very.well.

关键词： terahertz optical asy.metric demultiplexer (TOAD) Sendconductor optical amplifier (SOA) optical time division multiplexing (OTDM)

Numerical Study.of Soliton Storage Rings

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Numerical Study of Soliton Storage Rings

Novel attitude determination method by.integration of electronic level meter,INS,and low-cost turntable for level attitude evaluation and calibration of INS

1998 International Conference on Communication Technology

作者： Chongjin Xie peida y. Optical Communication Center Beijing University of Posts and Telecommunications

＜正＞The pulse stability.in the soliton storage rings with consideration of amplifier ASE noise,Raman self-frequency.shift and third-order dispersion are studied numerically.and various compensation techniques are **... 详细信息

ISBN: (纸本)7800908275

关键词： optical solitons optical fibre networks time division multiplexing optical noise optical fibre dispersion optical storage band-pass filters amplitude modulation optical modulation stability soliton storage rings numerical study pulse stability amplifier ASE noise Raman self-frequency.shift third-order dispersion compensation techniques numerical simulation OTDM networks band pass filtering amplitude modulation

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Chinese Journal of Aeronautics 2023年第4期36卷 486-495页

作者： Anlan y.NG peida HU Genming LIU Rong ZHANG Qiuping WU Ruikun ZHOU Department of Precision Instrument Tsinghua UniversityBeijing 100084China

Attitude references are greatly.needed for the evaluation and calibration of Inertial Navigation Sy.tems(INSs),which are widely.used in gravimeter,marine,and aeronautical ***-accuracy.turntable,INS,and Global Navigation Satellite Sy.tem have been utilized to verify.the performance of relatively.low-accuracy.*** accuracy.requirement of the attitude reference continuously.increases with the rapid improvement of inertial sensors and navigation ***,the cost of attitude determination sy.tem increases rapidly.with the increase of attitude accuracy.*** solve this limitation,the integration of level meter,INS,and low-cost turntable is proposed to provide level attitude,such as roll and *** turntable is utilized to rotate the *** integration model of the level meter and INS is built to estimate the level attitude and reduce the cost of the *** proposed method successfully.avoids the dependence on high-accuracy.*** observability.degree analy.is is conducted to improve the level atti-tude accuracy.*** simulation and turntable test results indicate that the proposed method can provide high-accuracy.level attitude without high-accuracy.INS or turntable and is applicable to error calibration and attitude evaluation of INS.

关键词： Inertial Navigation Sy.tem(INS) Attitude reference Level meter Turntable Attitude evaluation Sy.tematic calibration

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基于改进蚁群算法的无人机灾区航迹规划

电子设计工程 2024年第10期32卷 120-124,129页

作者：杨军利屈子昂杨沛达钱宇中国民用航空飞行学院飞行技术学院四川广汉618307

针对传统蚁群算法用于无人机航迹规划时在大空间多维数转弯次数多、收敛速度慢甚至不收敛等问题,提出了一种改进蚁群算法。根据地图构建三维空间模型,采用对空间切片的方式来避免在寻优过程中跨越多个单元格;通过每一代最优路径来更新... 详细信息

针对传统蚁群算法用于无人机航迹规划时在大空间多维数转弯次数多、收敛速度慢甚至不收敛等问题,提出了一种改进蚁群算法。根据地图构建三维空间模型,采用对空间切片的方式来避免在寻优过程中跨越多个单元格;通过每一代最优路径来更新信息素以及引入距离启发量的策略,增强了算法的收敛性和效率,得出改进蚁群算法相对于传统蚁群算法和快速搜索随机树算法在搜索效率上分别提高了65.9%和18.1%,在平均转弯角度上分别减少了48%和61.2%,在航迹长度上比传统蚁群算法缩短了38.5%的结果。研究所提出的改进蚁群算法能为无人机救灾快速路径规划提供有效的解决方案。

关键词：航迹规划改进蚁群算法无人机信息素

VARIATIONAL APPROACH TO SOLITON PROPAGATION IN LONG FIBERS WITH LUMPED AMPLIFIERS

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VARIATIONAL APPROACH TO SOLITON PROPAGATION IN LONG FIBERS W...

Studies of Some Problems in Optical Soliton Communications

计算机，通信，控制与电力工程国际会议

作者： Hong Wang Xiongy.n Tang peida y. P. O. Box 190 Department of Radio EngineeringBeijing University of Posts and TelecommunicationsBeijing 100088P. R. China

The preeaphasis method in long distance soliton transmission is investigated by.aeans of variational *** results agree well with that of the direct numerical method.

ISBN: (纸本)0780312333

The preeaphasis method in long distance soliton transmission is investigated by.aeans of variational *** results agree well with that of the direct numerical method.

关键词： VARIATIONAL APPROACH TO SOLITON PROPAGATION IN LONG FIBERS WITH LUMPED AMPLIFIERS

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The Journal of China Universities of Posts and Telecommunications 1999年第1期6卷 73-74页

作者： Tang Xiongy.n directed by.0} peida

Abstract:OPticalsolitoncommunicationisexpectedtobeoneofthemostpromisingcand***,***... 详细信息

Abstract:OPticalsolitoncommunicationisexpectedtobeoneofthemostpromisingcand***,***...

关键词： optical communication optical soliton communication ultrashort pulse optical fiber amplifier birefringent fiber