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Quasi-concave optimization of secrecy redundancy rate in HARQ-CC system

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Science China(Information Sciences) 2020年第2期63卷 160-173页

作者： Yue WU Shishu YIN jian zhou Pei YANG Hongwen YANG School of Management Science and Engineering Anhui University of Finance and Economics School of Information and Communication Engineering Beijing University of Posts and Telecommunications

In a hybrid automatic repeat request with chase combining(HARQ-CC) system, we analyze physical layer secure performance and determine the secrecy redundancy rate by proposed quasi-concave optimization methods with effective secrecy throughput(EST) criteria. First, key performance metrics,including connection outage probability(COP), secrecy outage probability(SOP), EST, and delay, are discussed. Then, under the constraint of COP, we optimize the secrecy redundancy rate to maximize the EST,which is a quasi-concave function, by both the bisection and fixed-point methods. Furthermore, under the simultaneous constraints of COP and SOP, the bisection and Lagrangian multiplier methods are applied to optimize the secrecy redundancy rate. From the comparison of the numerical and simulated results, it is concluded that EST demonstrates practical secure performance of HARQ-CC, and the proposed optimization methods adjust the secrecy redundancy rate for improved security.

关键词： physical layer security(PLS) hybrid automatic repeat request(HARQ) chase combining(CC) effective secrecy throughput(EST) quasi-concave optimization

Teleportation of Bipartite Entangled State Without Joint Measurement

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Communications in Theoretical Physics 2007年第4期47卷 633-635页

作者： zhou jian YANG Ming CAO Zhuo-Liang Key Laboratory of Opto-electronic Information Acquisition ＆ Manipulation Ministry of Education School of Physics ＆ Material Science Anhui University Hefei 230039 China Department of Physics Anqing Teacher＇s College Anqing 246011 China

In this paper, we present a probabilistic teleportation scheme for unknown bipartite entangled state. By using linear optical elements, we convert the Bell-state measurement into separated single-qubit measurements.

关键词： teleportation single-qubit measurement linear optical element

Teleportation of Multi-ionic GHZ States and Arbitrary Bipartite Ionic State via Linear Optics

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Communications in Theoretical Physics 2007年第5X期48卷 847-850页

作者： zhou jian DONG Ping CAO Zhuo-Liang The Scientific Research Department Anhui Xinhua University Hefei 230088 China Key Laboratory of Optoelectronic Information Acquisition and Manipulation of Ministry of Education and School of Physics and Material Science Anhui University Hefei 230039 China

We present a scheme for teleportation of multi-ionic GHZ states and arbitrary bipartite ionic state only by single-qubit measurements via linear optical elements. In our scheme, we avoid the difficulty of joint measurement and synchronizing the arrival time of the two scattered photons, which are faced by previous schemes. So our scheme can be realized easily within current experimental technology.

关键词： GHZ state teleportation linear optics

Internally Reuse Waste： Catalytic Asymmetric One-Pot Strecker Reaction of Fluoroalkyl Ketones, Anilines and TMSCN by Sequential Catalysis

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Chinese Journal of Chemistry 2018年第4期36卷 321-328页

作者： Yun-Lin Liu Xiao-Ping Yin jian zhou Shanghai Key Laboratory of Green Chemistry and Chemical Processes School of Chemistry and Molecular Engineering East China Normal University Shanghai 200062 China Current address: School of Chemistry and Chemical Engineering Guangzhou University Guangzhou Guangdong 510006 China Shanghai Engineering Research Center of Molecular Therapeutics and New Drug Development East China Normal University Shanghai 200062 China

We report a highly enantioselective one-pot facile synthesis of fluorinated Cα-tetrasubstituted amino nitriles from α-fluoroalkyl α-aryl keo tones, anilines, and TMSCN through a sequential p-TsOH catalyzed ketimine formation and chiral bifunctional tertiary amine mediated asymmetric Strecker reaction. This one-pot approach has two important advantages. First, it greatly improves the overall yield of the synthesis of chiral Cα-tetrasubstituted fluorinated aminonitriles from ketones, because the purification of a-fluorinated ketimines by column chromatography suffers from great yield loss. Second, it represents the first example of asymmetric tandem reactions that can simultaneously reuse the by-product and catalyst from the upstream step as a promoter and an additive to improve the reactivity and enantioselectivity of the subsequent catalytic enantioselective reaction, respectively. It could utilize the by-product H_2O generated in-situ from the ketimine formation step to activate TMSCN to form HCN, and concurrently reuse the remaining p-TsOH acid as an additive to improve enantioselectivity.

关键词： one-pot enantioselective Strecker reaction fluorine α-aminonitrile

Buckled Fiber Conductors with Resistance Stability under Strain

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Advanced Fiber Materials 2021年第3期3卷 149-159页

作者： Weisen Meng Mingyu Nie Zhiyu Liu jian zhou School of Materials Science and Engineering Sun Yat-Sen University GuangzhouGuangdong 510275China

The availability of fiber conductors that can be stretched to large extents without significantly changing resistance or con-ductivity could enable the advances of elastic conductors as electronic interconnects,electronic skins,stretchable sensors,wearable systems,and medical ***,the preparation of fiber conductors with high stretchability is crucial to the development of flexible electronic *** review summarizes the advances in constructing fiber conductors with an emphasis on recent developments of buckled structural design,fabrication methodologies,and strategies,with the ulti-mate goal of achieving good stability of resistance or conductivity at large *** review classifies the buckled fiber conductors into inner buckling and outer buckling,and related examples are summarized,providing a context that buckled fiber conductors are geared towards applications in electrical interconnects,wearable systems,and smart medical *** present challenges in this area are critically evaluated and our perspectives for improving the performance of the buckled fiber conductors for future applications are presented.

关键词： Buckled Fiber conductor Stretchability Resistance

Nearfield acoustic holography based on the equivalent source method

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Science China(Technological Sciences) 2005年第3期48卷 338-353页

作者： BI Chuanxing CHEN Xinzhao CHEN jian zhou Rong Dynamic Measuring Center Hefei University of TechnologyHefei 230009China Dynamic Measuring CenterHefei University of TechnologyHefei 230009China Dynamic Measuring CenterHefei University of TechnologyHefei 230009China Dynamic Measuring CenterHefei University of TechnologyHefei 230009China

On the basis of the nearfield acoustic holography (NAH) based on the distributed source boundary point method (DSBPM), a novel NAH based on the equivalent source method (ESM) is proposed. The theoretical model of the proposed method is established at first. And then, the error sensitivity and the reconstruction problems of a multi-source acoustic field and a semi-free acoustic field are analyzed, and the corresponding treatment methods are proposed. Subsequently, an experiment on a speaker is investigated to validate the feasibility and correctness of the method. In the method, no discretization is needed on the boundary of the vibrating body. The acoustic field is predicted directly by a set of weighted equivalent sources located inside the vibrating body. Therefore, the variable interpolation, the treatments of singular integrals and non-uniqueness of solutions in the characteristic wave number are avoided. Additionally, the method is adapted to arbitrary-shaped source, so it is really a meshless method. Furthermore, there are such merits as the simple principle, the high calculation efficiency and precision. It is valuabe for the NAH to be applied in the practical engineering field.

关键词： acoustic holography,equivalent source,acoustic radiation,noise source,regularization.

Impact of land use change on water resource allocation in the middle reaches of the Heihe River Basin in northwestern China

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Journal of Arid Land 2014年第3期6卷 273-286页

作者： YanYun NIAN Xin LI jian zhou XiaoLi HU Cold and Arid Regions Environmental and Engineering Research Institute Chinese Academy of Sciences College of Earth and Environmental Sciences Lanzhou University

In recent decades, China has been experiencing rapid economic development, population growth and urbanization. These processes have stressed the shortages of water resources in China, especially in the arid re- gions of northwestern China. In order to sustain the expanding cropland, people increased groundwater exploitation in these regions. The purpose of this study was to quantitatively analyze the changes in land use and water resources, and their relationship in the middle reaches of the Heihe River Basin, a typical inland river basin in northwest China. The data of land use change were interpreted using aerial photographs （1965） and Landsat TM images （1986 and 2007）. The data of irrigation water volume in the irrigation districts were spatialized in the middle reaches of the Heihe River Basin. The spatial variation of the groundwater depth was interpolated using the geo- statistical method. The results showed that the cultivated cropland area along oasis fringe increased by 15.38% and 43.60% during the periods 1965-1986 and 1986-2007, respectively. Surface water amount for irrigation had almost doubled from 1956 to 2010. The decrease of grassland area mainly occurred at the alluvial fan in front of the Qilian Mountains, with 36.47% during 1965-1986 and 38.56% during 1986-2007, respectively. The groundwater depth in front of the mountain constantly increased from 1986 to 2007. We found that the overuse of surface water and overexploitation of groundwater had direct consequences on the natural environments. We suggests that the efficiency of surface water resources use among different irrigation distdcts needs to be improved, which will significantly ease the conflicts between increasing water demand for irrigation and a shortage of water resources in the middle reaches of the Heihe River Basin.

关键词： watershed management land use groundwater irrigation arid region Heihe River Basin

Experimental study on characteristic curves of restoring forces of Populus alba var. pyramidalis

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Forestry Studies in China 2011年第4期13卷 315-320页

作者： zhou jian-zhong Key Laboratory of Soil and Water Conservation ＆ Desertification Combating of Ministry of Education School of Soil and WaterConservation Beijing Forestry University Beijing 100083 P. R. China

Static tests under cyclic loading were carried out on Populus alba var. pyramidalis to determine its characteristic curves of restoring forces. The results show that P alba var. pyramidalis had good elastic performance. There was degradation of strength and stiffness under cyclic loading and unloading, where characteristic curves of restoring forces ofP. alba var. pyrarnidalis assumed a ＂flat and contrary S-shape＂ form. Simultaneously, P alba vat. pyramidalis showed typical characteristics of brittle destruction under large high peak loading and unloading. Furthermore, dynamic tests were carried out under wind loads to obtain dynamic displacement curves and dynamic strain curves. P alba var. pyramidalis reflected its stochastic dynamic performance in building up its resistance to the stochastic wind loads and its dynamically hysteretic properties. The dynamic response of this species was random and fuzzy under stochastic wind loads. This study has theoretical significance and reference value to research on the static characteristics and wind-induced dynamic performance of forests.

关键词： Populus alba var. pyramidalis characteristic curve of restoring forces degradation of strength and stiffness stochasticwind loads

Predicting the Thickness of an Excavation Damaged Zone around the Roadway Using the DA-RF Hybrid Model

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Computer Modeling in Engineering & Sciences 2023年第9期136卷 2507-2526页

作者： Yuxin Chen Weixun Yong Chuanqi Li jian zhou School of Resources and Safety Engineering Central South UniversityChangsha410083China Laboratory 3SR CNRS UMR 5521Grenoble Alpes UniversityGrenoble38000France

After the excavation of the roadway,the original stress balance is destroyed,resulting in the redistribution of stress and the formation of an excavation damaged zone(EDZ)around the *** thickness of EDZ is the key basis for roadway stability discrimination and support structure design,and it is of great engineering significance to accurately predict the thickness of *** the advantages of machine learning(ML)in dealing with high-dimensional,nonlinear problems,a hybrid prediction model based on the random forest(RF)algorithm is developed in this *** model used the dragonfly algorithm(DA)to optimize two hyperparameters in RF,namely mtry and ntree,and used mean absolute error(MAE),rootmean square error(RMSE),determination coefficient(R^(2)),and variance accounted for(VAF)to evaluatemodel prediction performance.A database containing 217 sets of data was collected,with embedding depth(ED),drift span(DS),surrounding rock mass strength(RMS),joint index(JI)as input variables,and the excavation damaged zone thickness(EDZT)as output *** addition,four classic models,back propagation neural network(BPNN),extreme learning machine(ELM),radial basis function network(RBF),and RF were compared with the DA-RF *** results showed that the DARF mold had the best prediction performance(training set:MAE=0.1036,RMSE=0.1514,R^(2)=0.9577,VAF=94.2645;test set:MAE=0.1115,RMSE=0.1417,R^(2)=0.9423,VAF=94.0836).The results of the sensitivity analysis showed that the relative importance of each input variable was DS,ED,RMS,and JI from low to high.

关键词： Excavation damaged zone random forest dragonfly algorithm predictive model metaheuristic optimization