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Confidential Communication Through Chaos Encryption in Wireless Sensor Network

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Journal of China University of Mining and Technology 2007年第2期17卷 258-261页

作者： CHEN Shuai zhong xian-xin Electronic Staff Room of Physics Department Huainan Normal University Huainan Anhui 232001 China Key Laboratory of Optoelectronic Technology ＆ System Under State Ministry of Education Chongqing University Chongqing 400030 China

A new byte block cipher algorithm with discrete chaos and Feistel structure has been studied for confidential communication in wireless sensor network to improve security. After permutation,the byte block was encrypted through a Feistel structure in multiple turns and afterwards replaced again. The child keys are the composite sequence of discrete chaos and linear congruence sequences. Both the plain text and cipher text are of 8 bits. The number of keys is alterable. A nonlinear encryption function in the Feistel structure with chaos was constructed. The cipher algorithm was realized in the Micaz node,and the confidential communication experiment in wireless sensor network was completed success-fully. Additional ROM memory required for the cipher algorithm is 4144 bytes and an additional RAM memory 61 bytes. The cipher algorithm is nonlinear chaos and the Feistel structure holds the best of the RC6,DES and SKIPJACK cipher *** result shows that the algorithm needs a little memory and is safe at a high level.

关键词： algorithm encryption chaos wireless sensor network Feistel structure

Competition of Composition Fluctuation Modes in Weakly Segregated Salt-doped Symmetric Diblock Copolymers

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Chinese Journal of Polymer Science 2024年第9期42卷 1375-1385,I0008页

作者： Yuan-xin Zhou xian Kong South China Advanced Institute for Soft Matter Science and Technology School of Emergent Soft MatterSouth China University of TechnologyGuangzhou510640China Guangdong Provincial Key Laboratory of Functional and Intelligent Hybrid Materials and Devices South China University of TechnologyGuangzhou510640China

Salt-doped block copolymers have widespread applications in batteries,fuel cells,semiconductors,and various industries,where their properties crucially depend on phase separation ***,investigations into salt-doped diblock copolymers have predominantly focused on microphase separation,overlooking the segregation between ionic and polymeric *** study employs weak segregation theory to explore the interplay between phase separation dominated by the polymer-modulated mode and the salt-out-modulated mode,corresponding to microscopic and macroscopic phase separations,*** comparing diblock copolymers doped with salts to those doped with neutral solvents,we elucidate the significant role of charged species in modulating phase *** phase separation mode exhibits a transition between the polymer-modulated and salt-out-modulated modes at different *** systems doped with neutral solvents,this transition is stepwise,while in salt-ion-doped systems,it is *** a sufficiently large Flory-Huggins parameter between ions and polymers,the salt-out-modulated mode becomes dominant,promoting macrophase *** to the solvation effect of salt ions,salt-doped systems are more inclined to undergo microphase ***,we explore factors influencing the critical wavenumber of phase separation,including doping level and the Flory-Huggins parameters between two blocks and between ions and polymeric *** findings reveal that in a neutral solvent environment,these factors alter only the boundary between micro-and macro-phase separations,leaving the critical wavenumber unchanged in microphase separation ***,in a salt-doped environment,the critical wavenumber of microphase separation varies with these *** provides valuable insights into the pivotal role of electrostatics in the phase separation of salt-doped block copolymers.

关键词： Block copolymer Phase separation Field theory Salt-doped

Feasibility Study on Recovering Human-Occupied Vehicle with An Offshore Crane

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China Ocean Engineering 2024年第4期38卷 648-662页

作者： HAN Ming-yue XIE Peng xian Hao-yi zhong xin-xin CHEN Sheng-lin SUN Tie-rui SUN Feng-lei School of Ocean Engineering and Technology Sun Yat-Sen UniversityZhuhai 519082China Key Laboratory of Comprehensive Observation of Polar Environment(Sun Yat-sen University) Ministry of EducationZhuhai 519082China Guangzhou Marine Engineering Corporation Guangzhou 510250China

Launching and recovering human-occupied vehicles(HOVs)has always been a challenging *** current recovery process requires staff to manually complete the tethering task,which is inefficient and endangers the lives of *** paper suggests moving the recovery position from the surface to underwater at approximately half the wavelength of the water depth(30−50 m underwater),where the HOV experiences less environmental *** ROV equipped with a ultra-short baseline beacon(USBL)and a manipulator was used to complete the tethering ***,a shackle customized to the shape of the manipulator’s gripper is fitted to the end of the cable to simplify the tethering *** investigate the dynamic response of recovering the HOV using this suggested method,a comprehensive numerical model is developed in this *** effects of wind,surface waves,ocean currents,and nonlinear interaction between the installation vessel and the HOV are quantitatively *** results show that the proposed recovery method can reduce the motion amplitude of the HOV and that the wave has the greatest influence on the dynamic response of the HOV during the recovery *** model provides better insight into the proposed HOV recovery method and confirms the effectiveness of the heave compensation *** proposed approach aims to enhance safety and operational efficiency by reducing direct human involvement in the recovery process and mitigating potential *** finding holds particular significance,especially in environmentally sensitive areas,where reducing the impact on the surrounding ecosystem is crucial.

关键词： human-occupied vehicle recovery dynamic response active heave compensation

Polyoxometalates-derived ternary metal oxides electrocatalyst for N_(2) reduction under ambient conditions

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Tungsten 2024年第2期6卷 428-437页

作者： Meng-Le Yang zhong-xin Jin Xi-xian Cao xin-Ming Wang Hui-Yuan Ma Hai-Jun Pang Gui-xin Yang The School of Material Science and Chemical Engineering Harbin University of Science and TechnologyHarbin 150040China

Accelerating the breaking of the nitrogen nonpolar bond(N≡N)is an important factor to improve the effi ciency of the electro-catalytic nitrogen reduction reaction(e-NRR).In this work,polyoxometalates-derived FeMo-based ternary oxide materials MoO_(2)-Mo_(4)O_(11)-FeMoO_(4)@X(abbreviated as MoFeO@X,X represents the synthesis temperature of 650,750 and 850℃)were designed and synthesized for e-NRR under ambient *** scanning electron microscopy images of MoFeO@750 show an ellipsoidal-like structure(0.86×0.6μm).The relatively large specifi c surface area,formation of multiple interfaces,together with the synergistic eff ect of iron and molybdenum bimetals,would make MoFeO@X catalyst more easily absorb and activate N_(2)in the ***,the synthesized MoFeO@750 shows an optimal NH_(3)production rate of 16.57μg·h^(−1)·mg cat.^(−1)and Faradaic effi ciency of 12.33%at−0.3 V versus reversible hydrogen electrode(ν***),with outstanding electrochemical and structural stability.

关键词： Polyoxometalates Electrocatalytic nitrogen reduction reaction Ternary oxide Electrocatalyst

一类支持向量机中引导式量子粒子群优化机理及实现

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重庆大学学报（自然科学版） 2011年第2期34卷 108-112,119页

作者：姚富光钟先信重庆教育学院计算机科学系重庆400067 重庆大学光电技术及系统教育部重点实验室重庆400044

通过分析量子粒子群在一类超球面支持向量机训练优化的应用机理,提出一种基于引导式量子粒子群(D-QDPSO)的一类超球面支持向量机训练优化算法,根据Zoutendijk最速下行策略确定全局最优gbest的优化方向,计算引导粒子位置;同时在初始化时... 详细信息

通过分析量子粒子群在一类超球面支持向量机训练优化的应用机理,提出一种基于引导式量子粒子群(D-QDPSO)的一类超球面支持向量机训练优化算法,根据Zoutendijk最速下行策略确定全局最优gbest的优化方向,计算引导粒子位置;同时在初始化时根据序列最小优化算法(SMO)得到靠近最优解的近似位置,并以约束平面边界点作为初始化粒子,扩大了搜索范围。实验表明,D-QDPSO算法有较好的收敛性能和泛化性能,其误识率比SMO降低约0.12%,运算速度比LPSO提高2倍左右。

关键词：粒子群优化支持向量机 Zoutendijk最速下行策略引导粒子序列最小优化 LPSO

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声表面波扩频多符号检测器算法研究

压电与声光 2005年第4期27卷 339-342页

作者：刘积学钟先信重庆大学光电技术及系统教育部开放实验室

基于多符号检测的DM PSK信号处理算法在改善系统检测性能方面是一条行之有效的方法。对于直接序列扩频系统,当采用DM PSK调制方式时,同样会存在检测性能恶化问题。为此,该文提出了基于SAW匹配滤波器的DM PSK直接序列扩频多符号检测器算... 详细信息

基于多符号检测的DM PSK信号处理算法在改善系统检测性能方面是一条行之有效的方法。对于直接序列扩频系统,当采用DM PSK调制方式时,同样会存在检测性能恶化问题。为此,该文提出了基于SAW匹配滤波器的DM PSK直接序列扩频多符号检测器算法,并采用13位巴克码SAW抽头延迟线和固定延迟线组合设计对符号数N=3的DBPSK扩频多符号检测算法进行了实验系统验证,给出了相应结果。

关键词： DMPSK直接序列扩频声表面波(SAW) 多符号检测

Design of New SAWDQPSK Matched Filter

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Semiconductor Photonics and Technology 2006年第1期12卷 35-38页

作者： LIU Ji-xue zhong xian-xin Key Laboratory of Optoelectronic Technology ＆ System for Ministry of Education Chongqing University Chongqing 400044 CHN Sichuan Institute of Piezoelectric ＆ Acoustooptic Technology Chongqing 400060 CHN

A new surface acoustic Wave differential quadraphase shift key（SAW DQPSK） spread spectrum （SS） signal matched filter based on the fusion of SS and differential modulation is reported. The design of multi-phase coded SAW matched filter is proposed rather than another design of SAW DQPSK filter, which can cut in a half of the delay time of SAW DQPSK matched filter and SAW fixed delay line（FDL） used for differential demodulation. This breakthrough is made the system largely reduce a size and process much easily. This method can also be feasible in other SAW MPSK matched filter design especially when the modulation phase number is larger than 4. The design example and its experimental results are given.

关键词： DQPSK Differential modulationt Spread spectrum SAW Matched filter

Electrical characteristics of a fractional-order 3×n Fan network

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Communications in Theoretical Physics 2024年第4期76卷 176-187页

作者： Zhi-zhong Tan xin Wang Department of Physics Nantong UniversityNantong 226019China

In this article a new achievement of fractional-order 3×n Fan networks is *** the first step,the RT-I method is used to derive the general formulae of the equivalent impedance of fractional-order 3×n Fan *** the second part,the effects of five system parameters(L,C,n,α and β)on amplitude-frequency and phase-frequency characteristics are *** the same time,the amplitude-frequency and phase-frequency characteristics of the fractional order 3×n Fan network are revealed by Matlab *** work has important theoretical and practical significance for resistor network models in the field of natural science and engineering technology.

关键词： fractional-order circuit amplitude-frequency characteristics phase-frequency characteristics RT-V theory

复杂可编程逻辑器件设计中延时影响的仿真分析

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华南理工大学学报（自然科学版） 2005年第6期33卷 28-31页

作者：陈帅钟先信邵小良重庆大学光电技术及系统教育部重点实验室重庆400044

为分析复杂可编程逻辑器件延时性能对数字系统设计中延时的影响规律,针对数字逻辑延时单元核的数学模型,采用硬件描述语言和图形方式实现了基本数字逻辑延时单元核,通过数字核复用建立了多延时单元部件,并运用电子设计自动化软件,通过... 详细信息

为分析复杂可编程逻辑器件延时性能对数字系统设计中延时的影响规律,针对数字逻辑延时单元核的数学模型,采用硬件描述语言和图形方式实现了基本数字逻辑延时单元核,通过数字核复用建立了多延时单元部件,并运用电子设计自动化软件,通过选择不同的复杂可编程器件对延时单元进行了仿真分析.结果表明,数字逻辑设计中的延时与复杂可编程器件的延时性能、综合布局布线选择的逻辑块以及互连资源有关.所得到的结果为复杂数字逻辑系统的延时设计与分析提供了理论与实验依据.

关键词：复杂可编程逻辑器件复杂数字逻辑设计延时单元核仿真分析