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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

Bifurcations and Chaos in Duffing Equation

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Acta Mathematicae Applicatae Sinica 2007年第4期23卷 665-684页

作者： Meng Zhang jiang-ping Yang Oriential Scientific and Technologic Institute Hunan Agriculture University Changsha 410081 China College of Science China Agricultural University Beijing 100083 China

The Duffing equation with even-odd asymmetrical nonlinear-restoring force and one external forcing is investigated. The conditions of existence of primary resonance, second-order, third-order subharmonics, morder subharmonics and chaos are given by using the second-averaging method, the Melnikov method and bifurcation theory. Numerical simulations including bifurcation diagram, bifurcation surfaces and phase portraits show the consistence with the theoretical analysis. The numerical results also exhibit new dynamical behaviors including onset of chaos, chaos suddenly disappearing to periodic orbit, cascades of inverse period-doubling bifurcations, period-doubling bifurcation, symmetry period-doubling bifurcations of period-3 orbit, symmetrybreaking of periodic orbits, interleaving occurrence of chaotic behaviors and period-one orbit, a great abundance of periodic windows in transient chaotic regions with interior crises and boundary crisis and varied chaotic attractors. Our results show that many dynamical behaviors are strictly departure from the behaviors of the Duffing equation with odd-nonlinear restoring force.

关键词： Duffing equation Melnikov's method second-order averaging method bifurcations chaos

Kobayashi＇s and Teichmiiller＇s Metrics on the Teichmiiller Space of Symmetric Circle Homeomorphisms

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Acta Mathematica Sinica,English Series 2011年第3期27卷 617-624页

作者： Jun HU Yun ping jiang Department of Mathematics Brooklyn College of CUNY Brooklyn NY 11210 USA Department of Mathematics CUNY Graduate Center 365 Fifth Avenue New York NY 10016 USA Department of Mathematics Queens College of CUNY Flushing NY 11367 USA

We give a direct proof of a result of Earle, Gardiner and Lakic, that is, Kobayashi＇s metric and Teichmuller＇s metric coincide with each other on the Teichmfiller space of symmetric circle homeomorphisms.

关键词： Universal asymptotically conformal Teichmiiller space Teichmiiller's metric Kobayashi's metric

Advances in electrocatalysts for oxygen evolution reaction of water electrolysis-from metal oxides to carbon nanotubes

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Progress in Natural Science:Materials International 2015年第6期25卷 545-553页

作者： Yi Cheng San ping jiang Fuels and Energy Technology Institute & Department of Chemical Engineering Curtin University

The water electrolysis for hydrogen production is constrained by the thermodynamically unfavorable oxygen evolution reaction(OER),which requires input of a large amount of energy to drive the *** of the key challenges to increase the efficiency of the water electrolysis system is to develop highly effective and robust electrocatalysts for the *** the past 20–30 years,significant progresses have been made in the development of efficient electrocatalysts,including metal oxides,metal oxide-carbon nanotubes(CNTs) hybrid and metal-free CNTs based materials for the *** this critical review,the overall progress of metal oxides catalysts and the role of CNTs in the development of OER catalyst are summarized,and the latest development of new metal free CNTs-based OER catalyst is discussed.

关键词： Water electrolysis Oxygen reduction reaction Metal oxide Hybrid metal oxide/CNTs CNTs

A code-based approach for labeling in complex irregular regions

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2009年第10期10卷 1450-1460页

作者： Zhi-long LI Jun-jie CAO Xiu-ping LIU Zhi-xun SU School of Mathematical Sciences Dalian University of Technology Dalian 116024 China

Labeling information in a complex irregular region is a useful procedure occurring frequently in sheet metal and the furniture industry which will be beneficial in parts management.A fast code-based labeler(FCBL) is proposed to accomplish this objective in this *** region is first discretized,and then encoded by the Freeman encoding technique for providing the 2D regional information by 1D codes with redundancies *** enhance the encoding scheme to make it more suitable for our complex *** on the codes,searching algorithms are designed and can be extended with customized *** addition,by introducing a smart optimal direction estimation,the labeling speed and accuracy of FCBL are significantly *** with a large range of real data gained from industrial factories demonstrate the stability and millisecond-level speed of *** proposed method has been integrated into a shipbuilding CAD system,and plays a very important role in ship parts labeling process.

关键词： Labeling Freeman codes Region filling Optimal direction Shipbuilding

The synergistic catalysis on Co nanoparticles and CoNx sites of aniline-modified ZIF derived Co@NCs for oxidative esterification of HMF

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Chinese Chemical Letters 2021年第2期32卷 685-690页

作者： Tao Rui Guo-ping Lu Xin Zhao xun Cao Zhong Chen School of Chemical Engineering Nanjing University of Science&TechnologyNanjing 210094China School of Materials Science&Engineering Nanyang Technological UniversitySingapore 639798Singapore

An efficient sustainable and scalable strategy for the synthesis of porous cobalt/nitrogen co-doped carbons(Co@NCs) via pyrolysis of aniline-modified ZIFs,has been *** can coordinate and absorb on the surface of ZIF(ZIF-CoZn3-PhA),accelerate the precipitation of ZIFs,thus resulting in smaller ZIF particle ***,the aniline on the surface of ZIF-CoZn3-PhA promotes the formation of the protective carbon shell and smaller Co nanoparticles,and increases nitrogen content of the *** of these prope rties of Co@NC-PhA-3,the oxidative esterification of 5-hydroxymethylfurfural can be carried out under ambient *** to our experimental and computational results,a synergistic catalytic effect between CoNx sites and Co nanoparticles has been established,in which both Co nanoparticles and CoNx can activate O2 while Co nanoparticles bind and oxidize ***,the formation and release of active oxygen species in CoNx sites are reinfo rced by the electronic interaction between Co nanoparticles and CoNx.

关键词： Aniline-modified ZIF Porous cobalt/nitrogen co-doped carbon Synergistic catalysis on CoNx sites and Co nanoparticles Oxidative esterification 5-Hydroxymethylfurfural

A preliminary phylogenetic study of Paraphlomis(Lamiaceae)based on molecular and morphological evidence

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Plant Diversity 2021年第3期43卷 206-215页

作者： Ya-ping Chen Ang Liu xun-Lin Yu Chun-Lei Xiang CAS Key Laboratory for Plant Diversity and Biogeography of East Asia Kunming Institute of BotanyChinese Academy of SciencesKunming650201YunnanChina College of Forestry Central South University of Forestry and TechnologyChangsha410004HunanChina

Paraphlomis is a genus of Lamiaceae with about 30 species distributed mainly in subtropical *** this study,we carried out the first molecular phylogenetic analyses to elucidate the relationships within the genus based on two nuclear and four plastid DNA *** results,which recovered a species of Matsumurella within Paraphlomis,indicate that the genus is not *** two sections and most of the series previously described within the genus are also shown to be *** with morphological evidence,our study indicates that nutlet morphology rather than calyx morphology is of phylogenetic value for the infrageneric classification of ***,***,a new species from southern China,is here described,and ***,formerly treated as a variety of ***,is here resurrected as a distinct species within the genus.

关键词： Ajugoides Infrageneric classification Matsumurella Nutlet Paraphlomideae

Continuous Forcing Spectra of Even Polygonal Chains

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Acta Mathematicae Applicatae Sinica 2021年第2期37卷 337-347页

作者： He-ping ZHANG Xiao-yan jiang School of Mathematics and Statistics Lanzhou UniversityLanzhou 730000China School of Mathematics and Statistics Huizhou UniversityHuizhou 516007China

Let G be a graph that admits a perfect matching M.A forcing set S for a perfect matching M is a subset of M such that it is contained in no other perfect matchings of *** cardinality of a forcing set of M with the smallest size is called the forcing number of M,denoted by f(G,M).The forcing spectrum of G is defined as:Spec(G)={f(G,M)|M is a perfect matching of G}.In this paper,by applying the Ztransformation graph(resonance graph)we show that for any polyomino with perfect matchings and any even polygonal chain,their forcing spectra are integral *** we obtain some sharp bounds on maximum and minimum forcing numbers of hexagonal chains with given number of *** spectra of two extremal chains are determined.

关键词： perfect matching forcing number forcing spectrum polyomino even polygonal chain Z-transformation graph

Green Synthesis of Nitrogen-to-Ammonia Fixation: Past, Present, and Future

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Energy & Environmental Materials 2022年第2期5卷 452-457页

作者： Jianyun Zheng Li jiang Yanhong Lyu San ping jiang Shuangyin Wang State Key Laboratory of Chem/Bio-Sensing and Chemometrics College of Chemistry and Chemical EngineeringHunan UniversityChangsha 410082China Department of Educational Science Hunan First Normal UniversityChangsha 410205China Curtin University Perth WAAustralia

The nitrogen(N2)-to-ammonia(NH3)fixation driven by renewable energy has an attractive prospect to relieve the global warming and reduce the consumption of fossil ***,photocatalytic,electrochemical,and photoelectrochemical approaches are developed as the next-generation NH3 synthesis technologies to substitute the Haber–Bosch ***,the NH3 yield rate of nitrogen reduction reaction(NRR)by green approaches is extremely low,resulting in the current dilemma of NRR and contamination ***,in this mini review,the past advances on the sustainable NRR are briefly summarized in the three aspects as follows:the selectivity and adjustment of various catalysts,the type of electrolyte/solvent system,and the investigation of reaction ***,the recent critical activities in the area of sustainable NH3 synthesis are analyzed and discussed deeply,and a perspective for rational and healthy development of this area is provided positively。

关键词： current dilemma enhanced performances future challenges green synthesis nitrogen-to-ammonia fixation