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Securely min and k-th min computations with fully homomorphic encryption

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Science China(Information Sciences) 2018年第5期61卷 309-314页

作者： Bingbing JIANG yuan zhang Department of Computer Science and Technology Nanjing University

Due to the rapid development of smart phones that have decent computing and sensing abilities,it is now possible to outsource a sensing job to many smartphone *** can then perform computations on the data collected by the ***,the users may reveal their private information in the process of sending the collected data to the ***,the users may transmit the encrypted data to the server,meaning the server is not able to compute the extra knowledge about the plain data in the execution of the protocol.

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Design of a robust guidance law via active disturbance rejection control

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Journal of Systems Engineering and Electronics 2015年第2期26卷 353-358页

作者： Yanbo yuan Ke zhang School of Astronautics Northwestern Polytechnical University

Focusing on the three-dimensional guidance problem in case of target maneuvers and response delay of the autopilot, the missile guidance law utilizing active disturbance rejection control （ADRC） is proposed. Based on the nonlinear three-dimensional missile target engagement kinematics, the guidance model is es- tablished, The target acceleration is treated as a disturbance and the dynamics of the autopilot is considered by using a first-order model. A nonlinear continuous robust guidance law is designed by using a cascaded structure ADRC controller. In this method the disturbance is estimated by using the extended state observer （ESO） and compensated during each sampling period. Simulation results show that the proposed cascaded loop structure is a viable solution to the guidance law design and has strong robustness with respect to target maneuvers and response delay of the autopilot.

关键词： three-dimensional guidance active disturbance rejection control target maneuver autopilot response delay

Analysis of unmanned aerial vehicle navigation and height control system based on GPS

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Journal of Systems Engineering and Electronics 2010年第4期21卷 643-649页

作者： Jianjun zhang Hong yuan China Academy of Space Technology Beijing 100094 E R. China Academy of Opto-Electronics Chinese Academy of Sciences Beijing 100190 P. R. China

According to the characteristic of global positioning system（GPS） reflection signals,a GPS delay mapping receiver system scheme is put forward,which not only satisfies the unmanned aerial vehicle（UAV） guidance localization but also realizes height measurement.A code delay algorithm is put forward,which processes the direct and land reflected signal and outputs the navigation data and specular *** GPS terrain reflected echo signal mathematical equation is *** reflecting signal area,when the GPS signal passes the land,is *** height survey model reflected land surface characteristic is established.A simulation system which carries guidance localization of the UAV and the height measuring control through the GPS direct signal and the land reflected signal is designed,taken the GPS satellite as the illumination source,the receiver is put on the *** the UAV guidance signal,the GPS reflection signal and receiver＇s parallel processing are *** parallel processing reduces UAV＇s payload and raises system＇s operating *** simulation results confirms the validity of the model and also provides the basis for the UAV＇s optimization design.

关键词： height measuring global positioning system(GPS) reflected signal delay mapping receiver unmanned aerial vehicle(UAV).

Zinc-based fiber-shaped rechargeable batteries:Insights into structures,electrodes,and electrolytes

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Nano Research 2025年第1期18卷 278-293页

作者： Xuan zhang Hongcheng zhang Mengxiang Chen Jingqi Lu Evgeny Zhuravlev Jing Jiang Pin Liu Shengyang Dong Du yuan Guoyin Zhu Lianbo Ma Yizhou zhang Institute of Advanced Materials and Flexible Electronics(IAMFE) School of Chemistry and Materials ScienceNanjing University of Information Science and TechnologyNanjing 210044China School of Materials Science and Engineering Anhui University of TechnologyMaanshan 243002China College of Materials Science and Engineering Changsha University of Science and TechnologyChangsha 410004China

The rapid evolution of flexible wearable electronics has spurred a growing demand for energy storage devices,characterized by low-cost manufacturing processes,high safety standards,exceptional electrochemical performance and robust mechanical *** novel flexible devices,fiber-shaped batteries(FSBs)have emerged as prominent solutions exceptionally suited to future applications,owing to their unique one-dimensional(1D)architecture,remarkable flexibility,potential for miniaturization,adaptability to deformation and compatibility with the conventional textile *** the forefront research on fiber-shaped batteries,zincbased FSBs(ZFSBs)have garnered significant attentions,featured by the promising electrochemical properties of metallic *** enthusiasm is driven by the impressive capacity of Zn(820 mAh·g^(-1))and its low redox potential(Zn/Zn^(2+):-0.76 V *** hydrogen electrode).This review aims to consolidate recent achievements in the structural design,fabrication processes and electrode materials of flexible ***,we highlight three representative structural configurations:parallel type,twisted type and coaxial *** also place special emphasis on electrode modifications and electrolyte ***,we delve into the promising development opportunities and anticipate future challenges associated with ZFSBs,emphasizing their potential roles in powering the next generation of wearable electronics.

关键词： zinc-based batteries fiber-shape parallel type twisted type coaxial type

Turbine Endwall Film Cooling With Combustor-Turbine Interface Gap Leak- age Flow: Effect of Incidence Angle

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Journal of Thermal Science 2013年第2期22卷 135-144页

作者： zhang Yang yuan Xin Key Laboratory for Thermal Science and Power Engineering of Ministry of Education Tsinghua University

This paper is focused on the film cooling performance of combustor-turbine leakage flow at off-design condition. The influence of incidence angle on film cooling effectiveness on first-stage vane endwall with combustor-turbine interface slot is studied. A baseline slot configuration is tested in a low speed four-blade cascade comprising a large-scale model of the GE-E 3 Nozzle Guide Vane (NGV). The slot has a forward expansion angle of 30 deg. to the endwall surface. The Reynolds number based on the axial chord and inlet velocity of the free-stream flow is 3.5 × 10 5 and the testing is done in a four-blade cascade with low Mach number condition (0.1 at the inlet). The blowing ratio of the coolant through the interface gap varies from M = 0.1 to M = 0.3, while the blowing ratio varies from M = 0.7 to M = 1.3 for the endwall film cooling holes. The film-cooling effectiveness distributions are obtained using the pressure sensitive paint (PSP) technique. The results show that with an increasing blowing ratio the film-cooling effectiveness increases on the endwall. As the incidence angle varies from i = +10 deg. to i = 10 deg., at low blowing ratio, the averaged film-cooling effectiveness changes slightly near the leading edge suction side area. The case of i = +10 deg. has better film-cooling performance at the downstream part of this region where the axial chord is between 0.15 and 0.25. However, the disadvantage of positive incidence appears when the blowing ratio increases, especially at the upstream part of near suction side region where the axial chord is between 0 and 0.15. On the main passage endwall surface, as the incidence angle changes from i = +10 deg. to i = 10 deg., the averaged film-cooling effectiveness changes slightly and the negative incidence appears to be more effective for the downstream part film cooling of the endwall surface where the axial chord is between 0.6 and 0.8.

关键词： Film Cooling Endwall Pressure Sensitive Paint Leakage Flow

Effects of pH on photochemical decomposition of perfluorooctanoic acid in different atmospheres by 185 nm vacuum ultraviolet

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Journal of Environmental Sciences 2014年第11期26卷 2207-2214页

作者： yuan Wang Pengyi zhang State Key Joint Laboratory of Environmental Simulation and Pollution Control School of Environment Tsinghua University School of Chemistry and Chemical Engineering Guizhou University

Perfluorooctanoic acid （PFOA）, a persistent organic pollutant, receives increasing concerns due to its worldwide occurrence and resistance to most conventional treatment processes. The photochemical decomposition by 185 nm vacuum ultraviolet （VUV） is one of the efficient methods for PFOA decomposition. The effects of pH on PFOA decomposition in nitrogen atmosphere or oxygen atmosphere were investigated. At its original pH （4.5） of PFOA aqueous solution, PFOA decomposed efficiently both in nitrogen and in oxygen atmosphere. However, when the pH increased to 12.0, PFOA decomposition was greatly inhibited in oxygen atmosphere, while it was greatly accelerated in nitrogen atmosphere with a very short half-life time （9 rain）. Furthermore, fluorine atoms originally contained in PFOA molecules were almost completely transformed into fluoride ions. Two decomposi- tion pathways have been proposed to explain the PFOA decomposition under different conditions. In acidic and neutral solutions, PFOA predominantly decomposes via the direct photolysis in both atmospheres; while in the alkaline solution and in the absence of oxygen, the decomposition of PFOA is mainly induced by hydrated electrons.

关键词： Perfluorocarboxylic acids (PFCAs)185 nm vacuum ultraviolet Persistent organic pollutants Photochemical Perfluorinated compounds

Service composition based on discrete particle swarm optimization in military organization cloud cooperation

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Journal of Systems Engineering and Electronics 2016年第3期27卷 590-601页

作者： An zhang Haiyang Sun Zhili Tang yuan yuan School of Aeronautics Northwestern Polytechnical University School of Electronics and Information Northwestern Polytechnical University

This paper addresses the problem of service composition in military organization cloud cooperation（MOCC）. Military service providers（MSP） cooperate together to provide military resources for military service users（MSU）. A group of atom services, each of which has its level of quality of service（QoS）, can be combined together into a certain structure to form a composite service. Since there are a large number of atom services having the same function, the atom service is selected to participate in the composite service so as to fulfill users＇ will. In this paper a method based on discrete particle swarm optimization（DPSO） is proposed to tackle this problem. The method aims at selecting atom services from service repositories to constitute the composite service, satisfying the MSU＇s requirement on QoS. Since the QoS criteria include location-aware criteria and location-independent criteria, this method aims to get the composite service with the highest location-aware criteria and the best-match location-independent criteria. Simulations show that the DPSO has a better performance compared with the standard particle swarm optimization（PSO） and genetic algorithm（GA）.

关键词： service composition cloud cooperation discrete particle swarm optimization(DPSO)

Super-resolution DOA estimation for correlated off-grid signals via deep estimator

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Journal of Systems Engineering and Electronics 2022年第6期33卷 1096-1107页

作者： WU Shuang yuan Ye zhang Weike yuan Naichang Facility Design and Instrumentation Institute China Aerodynamics Research and Development CenterMianyang 621000China State Key Laboratory of Complex Electromagnetic Environment Effects on Electronics and Information System National University of Defense TechnologyChangsha 410073China

This paper develops a deep estimator framework of deep convolution networks(DCNs)for super-resolution direction of arrival(DOA)*** addition to the scenario of correlated signals,the quantization errors of the DCN are the major *** our deep estimator framework,one DCN is used for spectrum estimation with quantization errors,and the remaining two DCNs are used to estimate quantization *** propose training our estimator using the spatial sampled covariance matrix directly as our deep estimator’s input without any feature extraction ***,we reconstruct the original spatial spectrum from the spectrum estimate and quantization errors ***,the feasibility of the proposed deep estimator is analyzed in detail in this *** the deep estimator is appropriately trained,it can recover the correlated signals’spatial spectrum fast and *** results show that our estimator performs well in both resolution and estimation error compared with the state-of-the-art algorithms.

关键词： off-grid direction of arrival(DOA)estimation deep convolution network(DCN) correlated signal quantization error super-resolution

FURTHER EXTENSIONS OF SOME TRUNCATED HECKE TYPE IDENTITIES

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Acta Mathematica Scientia 2022年第1期42卷 73-90页

作者： helen W.J.zhang School of Mathematics Hunan UniversityChangsha 410082China

The main purpose of this paper is to generalize the study of the Hecke-Rogers type series,which are the extensions of truncated theorems obtained by Andrews,Merca,Wang and *** proofs rely heavily on the theory of Bail... 详细信息

关键词： theta functions truncated series Bailey pair Bailey transform