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Pt负载分层纳米结构氧化铝催化油酸脱羧的研究

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现代化工 2024年第5期44卷 187-193页

作者：王珉鑫石祥姜国平北方民族大学化学与化学工程学院宁夏银川750021 国家民委化工技术重点实验室宁夏银川750021 宁夏太阳能化学转化技术重点实验室宁夏银川750021

以MOF材料为前驱体合成三维形貌的氧化铝(3DAO),采用低温水热法合成了具有分层纳米结构的勃姆石(HNγ-AlOOH),最后经煅烧形成相同纳米结构的活性氧化铝(HNγ-Al_(2)O_(3))。以HNγ-Al_(2)O_(3)为载体制备了一系列负载量(0.5%、1%和1.5%)... 详细信息

以MOF材料为前驱体合成三维形貌的氧化铝(3DAO),采用低温水热法合成了具有分层纳米结构的勃姆石(HNγ-AlOOH),最后经煅烧形成相同纳米结构的活性氧化铝(HNγ-Al_(2)O_(3))。以HNγ-Al_(2)O_(3)为载体制备了一系列负载量(0.5%、1%和1.5%)的Pt/HNγ-Al_(2)O_(3)双功能催化剂,并将其用于油酸脱羧制备航空煤油。利用XRD、SEM、TEM、BET等对催化剂进行表征。结果表明,HNγ-Al_(2)O_(3)具有丰富的孔结构、较高的比表面积(266.8 m^(2)/g)和适宜的酸性。1%Pt/HNγ-Al_(2)O_(3)具有最优的催化性能,在反应温度为340℃、反应时间为5 h时,C_(8)~C_(17)的收率可达84.8%。

关键词：分层纳米结构氧化铝低温水热脱羧 C_(8)~C_(17)烷烃

Simple intra-signal-interference removing detector for HE-DCSK

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The Journal of China Universities of Posts and Telecommunications 2013年第6期20卷 102-108页

作者： YANG Hua jiang guo-ping College of Electronic Science and Engineering Nanjing University of Posts and Telecommunications College of Automation Nanjing University of Posts and Telecommunications

In this paper, a novel simple detector is designed to remove the intra-signal interference in high efficiency differential chaos shift keying （HE-DCSK） modulation scheme. With the help of data bit estimated before correlation detection, this new detector could remove the modulated chaotic segment that would form intra-signal interference component in the correlator output from every received information-bearing signal in HE-DCSK, leading to greatly and effectively improved system bit error rate （BER） performance. The effectiveness of this proposed detector is studied analytically based on the numerical integration method and evaluated by computer simulation in additive-white-Gaussian- noise （AWGN） channel. Simulation results reveal that the proposed detector can dramatically improve the overall BER performance of HE-DCSK even at relatively low signal noise ratio （SNR） levels.

关键词： chaos communications intra-signal interference removing high-efficiency differential chaos shift keying bit error rate

Zero-bit watermarking resisting geometric attacks based on composite-chaos optimized SVR model

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The Journal of China Universities of Posts and Telecommunications 2011年第2期18卷 94-101页

作者： GAO Guang-yong jiang guo-ping Center for Control & Intelligence Technology Nanjing University of Posts and Telecommunications Nanjing 210003 China School of Information Science & Technology Jiujiang University Jiujiang 332005 China

The problem to improve the performance of resisting geometric attacks in digital watermarking is addressed in this *** on the optimized support vector regression（SVR）,a zero-bit watermarking algorithm is *** proposed algorithm encrypts the watermarking image by using composite chaos with large key space and capacity against prediction,which can strengthen the safety of the proposed *** using the relationship between Tchebichef moment invariants of detected image and watermarking characteristics,the SVR training model optimized by composite chaos enhances the ability of resisting geometric *** analysis and simulations demonstrate that the proposed algorithm herein possesses better security and stronger robustness than some similar methods.

关键词： Tchebicbef moment invariants composite chaos SVR zero-bit watermarking

Epidemic spreading on scale-free networks with diversity of node anti-attack abilities

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The Journal of China Universities of Posts and Telecommunications 2010年第1期17卷 73-76,126页

作者： SONG Yu-rong jiang guo-ping Center for Control and Intelligence Technology Nanjing University of Posts and Telecommunications Nanjing 210003 China College of Automation Nanjing University of Posts and Telecommunications Nanjing 210003 China

In this article, a modified susceptible-infected-removed （SIR） model is proposed to study the influence of diversity of node anti-attack abilities on the threshold of propagation in scale-free networks. In particular, a vulnerability function related to node degree is introduced into the model to describe the diversity of a node anti-attack ability. Analytical results are derived using the mean-field theory and it is observed that the diversity of anti-attack of nodes in scale-free networks can increase effectively the threshold of epidemic propagation. The simulation results agree with the analytical results. The results show that the vulnerability functions can help adopt appropriate immunization strategies.

关键词： epidemic spreading scale-free network SIR model anti-attack vulnerability function

Framed slotted ALOHA with grouping tactic and binary selection for anti-collision in RFID systems

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The Journal of China Universities of Posts and Telecommunications 2009年第4期16卷 47-52页

作者： WANG Ya-qi jiang guo-ping WANG Jing Center for Control and Intelligence Technology Nanjing University of Posts and Telecommunications Nanjing 210003 China

In radio frequency identification （RFID） systems, tag collision arbitration is a significant issue for fast tag identification. This article proposes a novel tag anti-collision algorithm called framed slotted ALOHA with grouping tactic and binary selection （GB-FSA）. The novelty of GB-FSA algorithm is that the reader uses binary tree algorithm to identify the tags according to the collided slot counters information. Furthermore, to save slots, tags are randomly divided into several groups based on the number of collided binary bits in the identification codes （IDs） of tags, and then only the number of the first group of tags is estimated. Performance analysis and simulation results show that the GB-FSA algorithm improves the identification efficiency by 9.9%-16.3% compared to other ALOHA-based tag anti-collision algorithms when the number of tags is 1000.

关键词： RFID anti-collision binary tree identification efficiency

Structural Properties of Complex Networks

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南京邮电大学学报（自然科学版） 2010年第1期30卷 71-76页

作者： SHAO Fei jiang guo-ping College of Automation Nanjing University of Posts and Telecommunications Nanjing 210003 China Department of Information Technology Jinling Institute of Technology Nanjing 211169 China

When complex networks describe a wide range of systems in nature and society,it is increasingly recognized that the topology of real networks are governed by robust organizing *** we discuss the structural metrics such as average path length,clustering coefficient and degree distribution,the main models covering random graphs,small-world and scale-free networks,the interplay between structural properties and the synchronization of complex networks.

关键词：通信网网络安全网络协议 ER

Topology identification for a class of complex dynamical networks using output variables

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Chinese Physics B 2012年第2期21卷 193-201页

作者： Fan Chun-Xia Wan You-Hong jiang guo-ping College of Automation Nanjing University of Posts and TelecommunicationsNanjing 210003China

A problem of topology identification for complex dynamical networks is investigated in this paper. An adaptive observer is proposed to identify the topology of a complex dynamical networks based on the Lyapunov stability theory. Here the output of the network and the states of the observer are used to construct the updating law of the topology such that the communication resources from the network to its observer are saved. Some convergent criteria of the adaptive observer are derived in the form of linear inequality matrices. Several numerical examples are shown to demonstrate the effectiveness of the proposed observer.

关键词： complex dynamical networks topology identification adaptive observer output variables

Epidemic spreading in scale-free networks including the effect of individual vigilance

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Chinese Physics B 2012年第1期21卷 41-45页

作者： Gong Yong-Wang Song Yu-Rong jiang guo-ping College of Computer Nanjing University of Posts and TelecommunicationsNanjing 210003 China School of Information Engineering Yancheng Institute of TechnologyYancheng 224051China College of Automation Nanjing University of Posts and TelecommunicationsNanjing 210003 China

In this paper, we study the epidemic spreading in scale-flee networks and propose a new susceptible-infected- recovered （SIR） model that includes the effect of individual vigilance. In our model, the effective spreading rate is dynamically adjusted with the time evolution at the vigilance period. Using the mean-field theory, an analytical result is derived. It shows that individual vigilance has no effect on the epidemic threshold. The numerical simulations agree well with the analytical result. Purthermore, we investigate the effect of individual vigilance on the epidemic spreading speed. It is shown that individual vigilance can slow the epidemic spreading speed effectively and delay the arrival of peak epidemic infection.

关键词： scale-free network susceptible-infected-recovered model individual vigilance epidemicthreshold

Dynamic Framed Slotted ALOHA Algorithm Used in RFID System

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南京邮电大学学报（自然科学版） 2010年第1期30卷 26-32页

作者： WANG Ya-qi jiang guo-ping College of Automation Nanjing University of Posts and Telecommunications Nanjing 210003China

In radio frequency identification(RFID) systems,one of the most widely used anti-collision algorithms is the dynamic framed slotted ALOHA(DFSA)algorithm which usually uses two methods,one is tag estimation method (TEM) which estimates the number of tags around the reader,and the other is dynamic slot allocation (DSA) method which is the method to dynamically allocate the frame size according to the number of *** can achieve optimal system performance when the frame size is equal to the number of *** the number of tags becomes large,DFSA is not practical to increase the frame size infinitely,thus the application of DFSA algorithm is *** this paper a TEM method and a DSA method are proposed from two novel aspects respectively in order to use DFSA algorithm more effectively,and the analysis and comparison are given ***,the improved DFSA algorithm is proposed to solve the problem of DFSA *** the number of tags is large,if the improved DFSA algorithm is applied,the system efficiency that can be attained is not less than 50%.

关键词： ALOHA 通信网网络安全 RFID