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Computational mission analysis and conceptual system design for super low altitude satellite

Journal of Systems Engineering and Electronics 2014年第1期25卷 43-58页

作者： Ming Xu Jinlong Wang nan zhou School of Astronautics Beihang University

This paper deals with system engineering and design methodology for super low altitude satel ites in the view of the com-putational mission analysis. Due to the slight advance of imaging instruments, such as the focus of camera and the image element of charge coupled device （CCD）, it is an innovative and economical way to improve the camera’s resolution to enforce the satel ite to fly on the lower altitude orbit. DFH-3, the mature satel ite bus de-veloped by Chinese Academy of Space Technology, is employed to define the mass and power budgets for the computational mis-sion analysis and the detailed engineering design for super low altitude satel ites. An effective iterative algorithm is proposed to solve the ergodic representation of feasible mass and power bud-gets at the flight altitude under constraints. Besides, boundaries of mass or power exist for every altitude, where the upper boundary is derived from the maximum power, while the minimum thrust force holds the lower boundary before the power reaching the initial value. What’s more, an analytical algorithm is employed to numerical y investigate the coverage percentage over the altitude, so that the nominal altitude could be selected from al the feasi-ble altitudes based on both the mass and power budgets and the repetitive ground traces. The local time at the descending node is chosen for the nominal sun-synchronous orbit based on the average evaluation function. After determining the key orbital ele-ments based on the computational mission analysis, the detailed engineering design on the configuration and other subsystems, like power, telemetry telecontrol and communication （TT＆amp;C）, and attitude determination and control system （ADCS）, is performed based on the benchmark bus, besides, some improvements to the bus are also implemented to accommodate the flight at a super low altitude. Two operation strategies, drag-free closed-loop mode and on/off open-loop mode, are presented to maintain the satel-lite’s

关键词： super low altitude computational mission analysis,drag free control mass and power budget.

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Empirical Research upon the Influence of Interest Rate Changes upon the Real Estate Market Price

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学术界 2015年第6期 317-321页

作者： zhou nan Economics Department Changsha Commerce and Tourism College

VAR model is used to empirically test the influence of interest rate changes on real estate market price in this paper. The results show that there is a long- term,stable negative relationship between them,while the coefficient is relatively small,mainly because the transmission mechanism of interest rate is not smooth and the degree of marketization of interest rates is not high. Therefore,market- oriented reform of interest rate should be sped up and the interest rate should gradually be made to play the leading role in the regulation of real estate market price.

关键词： interest rate real estate market price VEC model VAR model

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Parseval Theory of Complex Wavelet Transform for Wavelet Family Including Rotational Parameters

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Communications in Theoretical Physics 2008年第9期50卷 598-602页

作者： zhou nan-Run JIA Fang Department of Electronics Information Engineering Nanchang University Nanchang 330031 China College of Physics ＆ Communication Electronics Jiangxi Normal University Nanchang 330022 China

A rotational parameter Rθ has been introduced to complex wavelet transform （CWT）. The rotational CWT （RCWT） corresponds to a matrix element 〈φ｜U2（θ;μ;κ）[F〉 in the context of quantum mechanics, where U2（θ;μ;κ） is a two-mode rotational displacing-squeezing operator in the 〈η｜ representation. Based on this, the Parseval theorem and the inversion formula of RCWT have been proved. The concise proof not only manifestly shows the merit of Dirac＇s representation theory but also leads to a new orthogonal property of complex mother wavelets in parameter space.

关键词： complex wavelet transform representation theory quantum mechanics

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Teleportation of Squeezed Entangled State

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Communications in Theoretical Physics 2007年第5期47卷 805-810页

作者： HU Li-Yun zhou nan-Run Department of Physics Shanghai Jiao Tong University Shanghai 200030 China Department of Electronics Information Engineering Nanchang University Nanchang 330029 China

Based on the coherent entangled state ｜a, x〉 we introduce the squeezed entangled state （SES）. Then we propose a teleportation protocol for the SES by using Einstein-Podolsky-Rosen entangled state ｜η〉 as a quantum channel. The calculation is greatly simplified by virtue of the Schmidt decompositions of both ｜a, x〉 and ｜η〉. Any bipartite states that can be expanded in terms of ｜a, x〉 may be teleported in this way due to the completeness of ｜a, x〉.

关键词： squeezed entangled state continuous variables EPR state teleportation

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Primary Exploration of the Feasibility of Passive Houses in Korea and China

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Journal of Harbin Institute of Technology(New Series) 2014年第4期21卷 69-76页

作者： Thorsten Schuetze Zheng-nan zhou Dept. of Architecture College of EngineeringSunKyunKwan University School of Architecture Tsinghua University

The transferability of European experiences with design,planning,construction and service of Passive-Houses to the specific conditions in China and Korea is investigated by the adaptation of the PassiveHouse principle to typical Korean and Chinese residential building,by the use of locally available building materials,components and building practices as well as under consideration of specific and typical ways of living in the two countries and cultures. The starting basis for the research is the analysis and evaluation of specific climate conditions,architecture,building practice as well as specific comfort criteria. The additional effort for the construction and service of Passive-Houses in Korea and China compared with typical contemporary residential buildings is investigated on the basis of a comparison of designs for Passive-Houses and for common buildings,including issues like the heating and cooling energy demand,heat and cool load as well as the required materials and components. The research results show that the described modifications of typical contemporary residential building constructions in China and Korea are realizable with locally available materials and feasible effort. They can reduce the energy demand for the service of domestic housing significantly and are in the range of European Passive Houses.

关键词： passive house feasibility East Asia

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Stability for a competing system of hierarchical age-structured populations

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International Journal of Biomathematics 2020年第7期13卷 325-345页

作者： Ze-Rong He nan zhou Institute of Operational Research and Cybernetics Hangzhou Dianzi University Hangzhou 310018P.R.China

In this paper,we are concerned with the stability for a model in the form of system of integro-partial differential equations,which governs the evolution of two competing age-structured *** age-specified environment is incorporated in the vital rates,which displays the hierarchy of *** a non-zero fixed-point result,we show the existence of positive *** conditions for the stability of steady states are derived by means of semigroup ***,numerical experiments are also presented.

关键词： Dominance rank population system equilibria stability semigroup of linear operators

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Observations of nitrous acid and its relative humidity dependence in Shanghai

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Journal of Environmental Sciences 2006年第5期18卷 910-915页

作者： HAO nan zhou Bin CHEN Dan CHEN Li-min Department of Environmental Science and Engineering Fudan University Shanghai 200433 China

Nitrous acid, HNO2, is an important precursor of OH radicals in the troposphere. Measurements of HNO2 and NO2, using differential optical absorption spectroscopy （DOAS）, were performed in Shanghai, China for a period from October 22, 2004 to January 4, 2005. The mean （and median） hourly concentrations of HNO2 and NO2 during this period were 1.1 （0.7） ppb and 24 （21.4） ppb respectively. A correlation between HNO2/NO2 and PM10 mass concentrations was obtained. This correlation suggests that significant heterogeneous chemical production of HNO2 may occur through NO2 reactions on aerosol surfaces. This hypothesis was further supported by detailed analysis of selected pollution episodes in this study. At the same time, the water dependence of HNO2 formation was studied by analysis of relative humidity （RH）. It showed that the maximum HNO2/NO2 ratio was increased along with RH below 70% and inhibited at RH〉70%.

关键词： DOAS heterogeneous formation nitrous acid PM,o aerosol relative humidity

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Effect of particle size and oxygen content on ignition and combustion of aluminum particles

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Chinese Journal of Aeronautics 2017年第6期30卷 1835-1843页

作者： Yu'nan zhou Jianzhong LIU Daolun LIANG Wei SHI Weijuan YANG Junhu zhou State Key Laboratory of Clean Energy Utilization Zhejiang University Hangzhou 310027 China

Particle size and oxygen content are two of the key factors that affect the ignition and combustion properties of aluminum particles. In this study, a laser ignition experimental system and flame test system were built to analyze the ignition and combustion characteristics and the flame morphology of aluminum particles. A thermobalance system was used to analyze the thermal oxidation characteristics. In addition, the microstructure of aluminum was analyzed by scanning electron microscopy. It was found that the oxidized products were some of the gas phase products agglomerated. Smaller particle size samples showed better combustion characteristics. The combustion intensity, self-sustaining combustion time and the burn-off rate showed a rising trend with the decrease in the particle size. Increasing the oxygen content in the atmosphere could improve the ignition and combustion characteristics of the samples. Four distinct stages were observed in the process of ignition and combustion. Small particle size samples had a larger flame height and luminance, and the self-sustaining combustion time was much *** distinct stages were observed during the thermal oxidation process. The degree of oxidation for small-sized samples was significantly higher than that for the larger particle size ***, it was observed that the higher the oxygen content, the higher the degree of oxidation was.

关键词： Aluminum Flame Ignition and combustion Laser Thermal analysis

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Investigation on the penetration of jacketed rods with striking velocities of 0.9-3.3 km/s into semi-infinite targets

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Defence Technology（防务技术） 2022年第3期18卷 476-489页

作者： Kui Tang Jin-xiang Wang Hai-ping Song nan zhou National Key Laboratory of Transient Physics Nanjing University of Science and TechnologyNanjing210094China China North Vehicle Research Institute Beijing100072China Department of Criminal Science and Technology Nanjing Forest Police CollegeNanjing210023China

In this study, a combined experimental, numerical and theoretical investigation is conducted on the penetration of semi-infinite 4340 steel targets by a homogeneous 93 W rod and two types of jacketed rods with striking velocities of 0.9-3.3 km/s. The results show that the jacketed rods produced typical“co-erosion” damage at all test velocities, except for the 93 W/1060 Al jacketed rod, which switched from an early “bi-erosion” damage to later “co-erosion” damage at a striking velocity of 936 m/s. However, the homogeneous 93 W rod always forms a large mushroom head during the penetration process. The damage mechanisms of these two types of jacketed rods differ for striking velocities of 0.9-2.0 km/s, but this difference gradually decreases with increased striking velocity. For velocities of 2.0-3.3 km/s, all three types of projectiles exhibit typical hydrodynamic penetration characteristics, and the damage mechanisms of the two types of jacketed rods are almost identical. For the same initial kinetic energy, the penetration performance of the jacketed rods is distinctly superior to that of the homogeneous 93 W *** with jacket density, jacket strength shows a more significant influence on the damage mechanism and penetration performance of the jacketed rod. Finally, an existing theoretical prediction model of the penetration depth of jacketed rods on semi-infinite targets in the co-erosion mode is modified. It transpires that-in terms of penetration depth-the modified theoretical model is in good agreement with the experimental and numerical observations for 93 W/TC4 and 93 W/1060 Al jacketed rods penetrating semi-infinite 4340 steel targets.

关键词： Jacketed rod Semi-infinite target Damage mechanism Penetration performance

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High thermal stability and blue-violet emitting phosphor CaYA1O4:Ti^4+with enhanced emission by Ca^2+vacancies

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Journal of Rare Earths 2020年第3期38卷 227-233页

作者： Mao Xia Yongli Zhang Minghui Li Yuan Zhong Simin Gu nan zhou Zhi zhou College of Science Hunan Agricultural UniversityChangsha 410128China Hunan Optical Agriculture Engineering Technology Research Center Changsha 410128China State Key Laboratory of Powder Metallurgy Central South UniversityChangsha 410083China

Blue-violet light can not only enhance the total content of biomass and glucoside but also enrich the taste of the ***,it is meaningful to study the blue-violet luminescent materials for plant *** this study,titanium(IV)-activated CaYAlO4(CYAO) phosphors were synthesized by conventional hightemperature solid-state reaction.X-ray powder diffraction was employed to analyze the crystalstructure of *** is found that the doped Ti^4+ ions do not change obviously the crystal structure of *** 246 nm excitation,CaYAl1-xO4:xTi^4+phosphors exhibit broad blue-violet emission band peaking at 395 nm,which can be attributed to the charge transfer of Ti^4+-O^2-.Moreover,this phosphor exhibits strong thermal *** luminescence emission intensity at 150℃maintained about 91 mol% of its initial value at room ***,the electron transition process and concentration quenching mechanism of CaYAl1-xO4:xTi^4+are discussed in *** excellent luminescent properties indicate that CaYAl1-xO4:xTi^4+phosphor may have promising application in indoor plant cultivation.

关键词： Blue-violet-emitting Ca^2+ vacancies Phosphors Plant growth lighting Ti^4+-activated

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