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Science China(Physics,Mechanics & Astronomy) 2017年第9期60卷 7-16页

作者： TianYu Ye ZhaoXu ji College of Information & Electronic Engineering Zhejiang Gongshang University

Quantum private comparison(QPC) aims to accomplish the equality comparison of the secrets from different users without disclosing their genuine contents by using the principles of quantum mechanics. In this paper, we summarize eight modes of quantum state preparation and transmission existing in current QPC protocols first. Then, by using the mode of scattered preparation and one-way convergent transmission, we construct a new multi-user quantum private comparison(MQPC) protocol with two-particle maximally entangled states, which can accomplish arbitrary pair's comparison of equality amongK users within one execution. Analysis turns out that its output correctness and its security against both the outside attack and the participant attack are guaranteed. The proposed MQPC protocol can be implemented with current technologies. It can be concluded that the mode of scattered preparation and one-way convergent transmission of quantum states is beneficial to designing the MQPC protocol which can accomplish arbitrary pair's comparison of equality among K users within one execution.

关键词： multi-user quantum private comparison (MQPC) scattered preparation one-way convergent transmission

An Improved SAR Image Denoising Method Based on Bootstrap Statistical Estimation with ICA Basis

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Chinese Journal of Electronics 2016年第4期25卷 786-792页

作者： ji jian LI Yang School of Computer Science and Technology Xidian University Shaanxi Automobile Group Co. Ltd

A new method for Synthetic aperture radar(SAR) image denoising is *** prior information of speckle statistical model can be exploited to judge its *** basis of SAR image can be estimated by Independent component analysis(ICA),and these bases can be divided into two different subspaces(noise and real signal subspaces) through a linear *** parametric Bootstrap estimates the parameters of speckle statistical model on the noise signal subspace,and the nonparametric Bootstrap can estimate the distribution of real image on the real signal *** to different results estimated by Bootstrap,corresponding Maximum a posterior probability(MAP) filter will be selected for image denoising,using the noise model’s parameter for adaptive *** show that the image processed by this new method can achieve a better visual perception and objective evaluation results.

关键词： Synthetic aperture radar(SAR) Image denoising Independent component analysis(ICA) basis Bootstrap Maximum a posterior probability(MAP)

Preparation of REPO_4(RE=La–Gd) nanorods from an ionic liquid extraction system and luminescent properties of CePO_4:Tb^(3+)

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Rare Metals 2019年第2期38卷 122-127页

作者： Yang Zhang ji Chen State Key Laboratory of Rare Earth Resources Utilization Changchun Institution of Applied Chemistry Chinese Academy of Sciences Graduate School of Chinese Academy of Sciences

Uniform nanorods of rare earth phosphate(REPO_4, RE = La–Gd) nanocrystals were prepared in a properly designed ionic liquid extraction system by a stripping precipitation method. Rare earth ions were extracted into the organic phase at first; after that, the loaded organic phase was stripped by aqueous solution of PO_4^(3-) under stirring at room temperature within 5 *** extractant used here is a bifunctional ionic liquid extractant called [A336][cyanex272]. The products are hexagonal phase in crystal structure, and their morphology is nanorods. The diameter of the products is from 30 to 50 nm, and the length increases from 200 nm to 2 μm gradually. Besides, the ionic liquid-absorbed CePO_4:Tb^(3+) nanorods show improved luminescent emitting intensity and lifetime. Based on the results, a possible growth mechanism of the REPO_4(RE = La–Gd) nanorods is proposed, where the extractants here also play roles of structure-directing agents and surfactants during the formation process of nanocrystals.

关键词： Ionic liquid Extraction Rare earth Luminescence

Effect of droplet heat content distribution on humping formation in high speed GMAW

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Acta Metallurgica Sinica(English Letters) 2011年第6期24卷 457-465页

作者： ji CHEN Chuansong WU MOE Key Laboratory for Liquid-Solid Structure Evolution and Materials Processing Institute of Materials Joining Shandong University Jinan 250061 China State Key Laboratory for Advanced Welding ＆ Joining Harbin Institute of Technology Harbin 150001 China BAM Federal Institute for Materials Research and Testing Division V.5 Safety of Joined Components Berlin 12205 Germany

The momentum of strong backward flowing melt jet and the thermal action from transferred droplets are two dominating factors affecting the formation of humping bead in high speed gas metal arc welding （GMAW）. Appropriate describing the influ- ence of the distribution mode of droplet heat content in the weld pool is essential to understand the physical mechanism of humping bead formation. Based on the exper- imental results, four kinds of droplet heat content distribution modes are proposed and employed to calculate the transient evolution of the temperature field and weld pool during high speed GMAW process. Through making comparison of predicted and measured weld bead dimensions, a suitable and adaptive distribution mode of droplet heat content is found, i.e., droplet heat content is distributed in bottom layer of gouging region at the front of weld pool, and is averagely distributed in the whole layer at the rear of weld pool. The proposed mode is also validated by experimental observation of the weld pool images and measured by geometric dimensions of the weld bead.

关键词： High speed GMAW Hump forming mechanism Droplet heat content Numerical analysis

The Convergence of Set-Valued Scenario Approach for Downside Risk Minimization

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Journal of Systems Science & Complexity 2016年第3期29卷 722-735页

作者： ji Xiaodong ZHU Shushang Department of Economics College of BusinessHebei Normal University Department of Finance and Investment Sun Yat-Sen Business SchoolSun Yat-Sen University

Scenario approach is a widely used tool in portfolio risk management,however,it often runs into dilemma when determining the distribution of asset returns with insufficient information,which will be used to simulate the *** the quality of generated scenarios are not guaranteed even when the distribution of asset returns is known exactly.A set-valued scenario approach was proposed by Zhu,et al.(2015)as a possible *** a necessary supplement of the results proposed by Zhu,et al.(2015),this paper theoretically investigates the convergent property of the numerical solution based on the set-valued scenario approach under the condition that the underlying distribution is known.

关键词： Convergence downside risk portfolio risk management set-valued scenarios.

Artificial boundary conditions for out-of-plane motion in penta-graphene

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Acta Mechanica Sinica 2017年第6期33卷 992-998页

作者： Songsong ji Shaoqiang Tang MoE Key Laboratory of High Energy Density Physics Simulations Center for Applied Physics and Technology Key Laboratory of Turbulence and Complex SystemsCollege of Engineering Peking University Beijing 100871China

In this paper, artificial boundary conditions are designed for out-of-plane waves in penta-graphene, a newly proposed allotrope of carbon. By matching the dispersion relation for acoustic branch phonons in the long wave limit, we determine parameters in proposed linear constraints among displacements and velocities at the boundary and nearby atoms. Reflection analysis for normal incidences and a numerical test demonstrate the effectiveness of the artificial boundary conditions. These conditions may be used for studying mechanical behaviours of the novel complex lattice of penta-graphene. © 2017 The Chinese Society of Theoretical and Applied Mechanics; Institute of Mechanics, Chinese Academy of Sciences and Springer-Verlag Berlin Heidelberg

关键词： Carbon Graphene Reflection

Dynamic performance of angle-steel concrete columns under low cyclic loading-II:parametric study

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Earthquake Engineering and Engineering Vibration 2008年第1期7卷 137-146页

作者： Zheng Wenzhong ji jing School of Civil Engineering Harbin Institute of Technology No.204 Haihe Road Harbin 150090 China

Tests of nine angle-steel concrete column （ASCC） specimens under low cyclic loading are described in a companion paper （Zheng and ji, 2008）. In this paper, the skeleton curves from the numerical simulation are presented, and show good agreement with the test results. Furthermore, parametric studies are conducted to explore the influence of factors such as the axial compression ratio, shear steel plate ratio, steel ratio, prismatic concrete compression strength, yield strength of angle steel and shear span ratio, etc., on the monotonic load-displacement curves of the ASCCs. Based on a statistical analysis of the calculated results, hysteretic models for load-displacement and moment-curvature are proposed, which agree well with the test results. Finally, some suggestions concerning the conformation of ASCCs are proposed, which could be useful in engineering practice.

关键词： low cyclic loading angle-steel concrete column shear-span ratio steel plate stirrup hysteretic model

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Representation of global precipitation anomalies using four major climate patterns

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Science China(Technological Sciences) 2015年第5期58卷 927-934页

作者： CHEN ji CHUNG ChiHang Department of Civil Engineering The University of Hong Kong

This study aims at finding the dominant climate patterns that influence the precipitation anomalies for different regions over the world. To this end, a multiple linear regression model is employed to represent the impact of four major climate patterns(El Ni?o-Southern Oscillation(ENSO), Indian Ocean Dipole(IOD), Arctic Oscillation(AO) and Antarctic Oscillation(AAO)) on the global precipitation anomalies. The normalized climate pattern indexes and normalized precipitation anomalies are used in the regression model. For the Northern Hemisphere, the three predictors used are the normalized NINO3.4 index(representing ENSO), normalized DMI(representing IOD) and normalized AO index; for the Southern Hemisphere, also three indexes are used as three predictors, and the normalized AO index is replaced by the normalized AAO index. The influences brought by each climate pattern can be represented by the magnitude of the corresponding regression coefficients, and the dominant climate patterns are those with the largest magnitude. The study results show that the precipitation anomalies in the northern part of South America and the northwestern part of Southeast Asia are mainly influenced by ENSO. The precipitation anomalies in East Africa and the southwestern part of Southeast Asia are mainly influenced by IOD. The precipitation anomalies in Europe and west coast of North America are mainly influenced by AO; the precipitation anomalies in the eastern part and southern part of South America, southern part of Africa, and the northeastern Australia are mainly influenced by AAO. These findings are consistent with the general understanding on the teleconnection features of the four climate patterns. Further, the regression model can be used for predicting precipitation anomalies through use of these major climate patterns.

关键词： normalized ENSO Southeast representing Australia southwestern Arctic trained instead brought

Performance analysis and threshold selection for cooperative multiple packet reception based on NDMA

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Journal of Systems Engineering and Electronics 2009年第5期20卷 920-928页

作者： ji Wei Zheng Baoyu Coll. of Telecommunications & Information Engineering Nanjing Univ. of Posts 8z Telecommunications Nanjing 210003 P. R. China Electronic Engineering Dept. Shanghai Jiaotong Univ. Shanghai 200240 P. R. China

To accurately assess the performance of cooperative multiple packet reception （MPR） based on network-assisted diversity multiple access （NDMA）, non-ideal collision detection is introduced in ALLIANCES （ALLow improved access in the network via cooperation and energy savings）. To provide a unified anatysis frame- work, the length of cooperative transmission epoch is fixed to the detected collision order. The mathematical analysis of potential throughput （PTP） and potential packet loss rate （PPLR） are given under a pessimistic assumption and an optimistic assumption. According to the analysis of PTP and PPLR, threshold selection is done to optimize system performances, e.g. the optimal threshold should guarantee PTP to be maximum or guarantee PPLR to be minimum. In simulations, the thresholds are selected according to PTP under the pessimistic assumption. Simulation results show that the proposed cooperative MPR scheme can achieve higher throughput than NDMA and slotted ALOHA schemes.

关键词： cooperative diversity multiple packet reception network-assisted diversity multiple access collision detection.

Synthesis,Growth Mechanism,and Applications of Zinc Oxide Nanomaterials

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Journal of Materials Science & Technology 2008年第4期24卷 457-472页

作者： Shulin ji Changhui YE Anhui Key Laboratory of Nanomaterials and Technology and Key Laboratory of Materials Physics Institute of SolidState Physics Chinese Academy of Sciences Hefei 230031 China

This article reviews recent progresses in growth mechanism, synthesis, and applications of zinc oxide nano-materials （mainly focusing on one-dimensional （1D） nanomaterials）. In the first part of this article, we briefly introduce the importance, the synthesis methods and growth mechanisms, the properties and applications of ZnO 1D nanomaterials. In the second part of this article, the growth mechanisms of ZnO 1D nanomaterials will be discussed in detail in the framework of vapor-liquid-solid （VLS）, vapor-solid （VS）, and aqueous solution growth （ASG） approaches. Both qualitative and quantitative information will be provided to show how a controlled synthesis of ZnO 1D nanomaterials can be achieved. In the third part of this article, we present recent progresses in our group for the synthesis of ZnO 1D nanomaterials, and the results from other groups will only be mentioned briefly. Especially, experiment designing according to theories will be elaborated to demonstrate the concept of controlled synthesis. In the fourth part of this article, the properties and potential applications of ZnO 1D nanomaterials will be treated. Finally, a summary part will be presented in the fifth section. The future trend of research for ZnO 1D nanomaterials will be pointed out and key issues to be solved will be proposed.

关键词： Zinc Oxide One-dimensional Nanomaterials Controlled synthesis