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Sensitivity function analysis of gravitational wave detection with single-laser and large-momentum-transfer atomic sensors

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Research in Astronomy and Astrophysics 2015年第3期15卷 333-347页

作者： Biao Tang Bao-Cheng zhang Lin Zhou Jin Wang Ming-sheng zhan State Key Laboratory of Magnetic Resonances and Atomic and Molecular Physics Wuhan Institute of Physics and Mathematics Chinese Academy of Sciences University of Chinese Academy of Sciences

Recently, a configuration using atomic interferometers （AIs） had been sug- gested for the detection of gravitational waves. A new AI with some additional laser pulses for implementing large momentum transfer was also put forward, in order to reduce the effect of shot noise and laser frequency noise. We use a sensitivity function to analyze all possible configurations of the new AI and to distinguish how many mo- menta are transferred in a specific configuration. By analyzing the new configuration, we further explore a detection scheme for gravitational waves, in particular, that ame- liorates laser frequency noise. We find that the amelioration occurs in such a scheme, but novelly, in some cases, the frequency noise can be canceled completely by using a proper data processing method.

关键词： gravitational wave detection -- atomic interferometer-- laser frequencynoise

Derivation of the Spiral Motion of an Eruptive Prominence and Its Explanation

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Chinese Journal of Astronomy and Astrophysics 2006年第5期6卷 617-624页

作者： Xiao-Ma Gu Shu-Hua Zhong Hong-Fei Liang La-sheng zhan National Astronomical Observatories / Yunnan Observatory Chinese Academy of Sciences Kunming650011 Jingdezhen Ceramic Institute Jingdezhen 333000

A 2D velocity field of the eruptive prominence （EP） of 1991 March 5 is obtained from its spectral data observed at the Yunnan Observatory and the velocity distributions along the entrance slit are derived for different observing frames. Under the assumption that matter in the EP undergoes axial, radial and possible rotational motions, we construct a theoretical velocity distribution of the EP along the entrance slit, to derive, by fitting, the angular velocity of rotation ω and the other three parameters （axial velocity v0, radial velocity vr and the angle between the EP plane and the line of sight Ф）. We found： an averaged angular velocity ω of 3.0 × 10^-3 arc s^-1 and the variation of ω with the height above the solar limb. As the EP rises, the matter within it in fact moves along a spiral path around its axis. The spiral motion may be explained by the theory of plasma ‘double pole diffusion＇（DPD） caused by a sharp density gradient between the eruptive prominence and the surrounding corona. A theoretical angular velocity ω′ is estimated based on the DPD and basically coincides with ω obtained from the optimal velocity fitting.

关键词： Sun eruptive prominence -- Sun Spiral motion

Quantitative estimation of land surface evapotranspiration in Taiwan based on MODIS data

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Water Science and Engineering 2011年第3期4卷 237-245页

作者： Che-sheng zhan Jie ZHAO Hui-xiao WANG Jian YIN Key Laboratory of Water Cycle and Related Land Surface Processes Institute of Geographic Sciences and Natural Resources Research CAS Beijing 100101 P. R. China Beijing Tsinghua Urban Planning and Design Institute Beijing 100085 P R. China Key Laboratory of Water and Sediment Sciences Ministry ofEducation College of Water Sciences Beijing Normal University Beijing 100875 P R. China

Land surface evapotranspiration （ET） determines the local and regional water-heat balances. Accurate estimation of regional surface ET provides a scientific basis for the formulation and implementation of water conservation programs. This study set up a table of the momentum roughness length and zero-plane displacement related with land cover and an empirical relationship between land surface temperature and air temperature. A revised quantitative remote sensing ET model, the SEBS-Taiwan model, was developed. Based on Moderate Resolution Imaging Spectroradiometer （MODIS） data, SEBS-Taiwan was used to simulate and evaluate the typical actual daily ET values in different seasons of 2002 and 2003 in Taiwan. SEBS-Taiwan generally performed well and could accurately simulate the actual daily ET. The simulated daily ET values matched the observed values satisfactorily. The results indicate that the net regional solar radiation, evaporation ratio, and surface ET values for the whole area of Taiwan are larger in summer than in spring, and larger in autumn than in winter. The results also show that the regional average daily ET values of 2002 are a little higher than those of 2003. Through analysis of the ET values from different types of land cover, we found that forest has the largest ET value, while water areas, bare land, and urban areas have the lowest ET values. Generally, the Northern Taiwan Region, including llan County, Nantou County, and Hualien County, has higher ET values, while other cities, such as Chiayi, Taichung, and Tainan, have lower ET values.

关键词： evapotranspiration quantitative remote sensing, MODIS SEBS model, Taiwan

New Members of High-Energy-Density Compounds: YN5 and YN8

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Chinese Physics Letters 2021年第6期38卷 49-53页

作者： Jun-Yi Miao zhan-sheng Lu Feng Peng Cheng Lu School of Physics Henan Normal UniversityXinxiang 453007China College of Physics and Electronic Information Luoyang Normal UniversityLuoyang 471022China School of Mathematics and Physics China University of Geosciences(Wuhan)Wuhan 430074China

Polymeric nitrogen is a promising candidate for a high-energy-density material. Synthesis of energetic compounds with high chemical stability under ambient conditions is still a challenging problem. Here we report a theoretical study on yttrium nitrides by first principles calculations combined with an effective crystal structure search method. It is found that many yttrium nitrides with high nitrogen content can be formed under relatively moderate pressures. The results indicate that the nitrogen-rich YN_(5) and YN_(8) compounds are recoverable as metastable high-energy materials under ambient conditions, and can release enormous energies(2.51 kJ·g^(-1) and 3.18 kJ·g^(-1)) while decomposing to molecular nitrogen and YN. Our findings enrich the family of transition metal nitrides, and open avenues for design and synthesis of novel high-energy-density materials.

关键词： material ambient yttrium

Time-optimal control of multiple unmanned aerial vehicles with human control input

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International Journal of Intelligent Computing and Cybernetics 2019年第1期12卷 138-152页

作者： Tao Han Bo Xiao Xi-sheng zhan Jie Wu Hongling Gao Hubei Normal University HuangshiChina College of Mechatronics and Control Engineering Hubei Normal UniversityHuangshiChina

Purpose–The purpose of this paper is to investigate time-optimal control problems for multiple unmanned aerial vehicle(UAV)systems to achieve predefined flying ***/methodology/approach–Two time-optimal protocols are proposed for the situations with or without human control input,***,Pontryagin’s minimum principle approach is applied to deal with the time-optimal control problems for UAV systems,where the cost function,the initial and terminal conditions are given in ***,necessary conditions are derived to ensure that the given performance index is ***–The effectiveness of the obtained time-optimal control protocols is verified by two contrastive numerical simulation ***,the proposed protocolscan successfully achieve the prescribed flying ***/value–This paper proposes a solution to solve the time-optimal control problems for multiple UAV systems to achieve predefined flying shape.

关键词： Unmanned aerial vehicle Human control input Time-optimal control,Pontryagin’s minimum principle

Design parameter optimization method for a prestressed steel structure driven by multi-factor coupling

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Frontiers of Structural and Civil Engineering 2024年第7期18卷 1066-1083页

作者： Guo-Liang SHI zhan-sheng LIU De-Chun LU Qing-Wen zhanG Majid DEZHKAM Ze-Qiang WANG Faculty of Architecture Civil and Transportation EngineeringBeijing University of TechnologyBeijing 100124China The Key Laboratory of Urban Security and Disaster Engineering of the Ministry of Education Beijing University of TechnologyBeijing 100124China Beijing Building Construction Research Institute Co. Ltd.Beijing 100039China

To achieve efficient structural design,it is crucial to reduce the cost of materials while ensuring structural *** study proposes an optimization method for design parameters(DPs)in a prestressed steel structure driven by multi-factor *** accomplish this,a numerical proxy model of prestressed steel structures is established with integration of DPs and mechanical parameters(MPs).A data association-parameter analysis-optimization selection system is established.A correlation between DPs and MPs is established using a back propagation(BP)neural *** correlation provides samples for parameter analysis and optimization *** are used to characterize the safety of the *** on the safety grade analysis,the key DPs that affect the mechanical properties of the structure are obtained.A mapping function is created to match the MPs and the key *** optimal structural DPs are obtained by setting structural materials as the optimization objective and safety energy as the constraint *** theoretical model is applied to an 80-m-span gymnasium and verified with a scale test physical *** MPs obtained using the proposed method are in good agreement with the experimental *** with the traditional design method,the design cycle can be shortened by more than 90%.Driven by the optimal selection method,a saving of more than 20% can be achieved through reduction of structural material ***,the cross-sectional dimensions of radial cables have a substantial influence on vertical *** initial tension and cross-sectional size of the upper radial cable exhibit the most pronounced impact on the stress distribution in that *** initial tension and cross-sectional size of the lower radial cable hold the greatest sway over the stress distribution in that cable.

关键词： structure design association relationship performance analysis optimum selection experimental verification

Parameter identification and global sensitivity analysis of Xin'anjiang model using meta-modeling approach

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Water Science and Engineering 2013年第1期6卷 1-17页

作者： Xiao-meng SONG Fan-zhe KONG Che-sheng zhan Ji-wei HAN Xin-hua zhanG Hydrology and Water Resources Department Nanjing Hydraulic Research Institute School of Resource and Earth Science China University of Mining and Technology Key Laboratory of Water Cycle and Related Land Surface Processes Institute of Geographic Sciences and Natural Resources ResearchChinese Academy of Sciences State Key Laboratory of Hydraulics and Mountain River Engineering Sichuan University

Parameter identification, model calibration, and uncertainty quantification are important steps in the model-building process, and are necessary for obtaining credible results and valuable information. Sensitivity analysis of hydrological model is a key step in model uncertainty quantification, which can identify the dominant parameters, reduce the model calibration uncertainty, and enhance the model optimization efficiency. There are, however, some shortcomings in classical approaches, including the long duration of time and high computation cost required to quantitatively assess the sensitivity of a multiple-parameter hydrological model. For this reason, a two-step statistical evaluation framework using global techniques is presented. It is based on （1） a screening method （Morris） for qualitative ranking of parameters, and （2） a variance-based method integrated with a meta-model for quantitative sensitivity analysis, i.e., the Sobol method integrated with the response surface model （RSMSobol）. First, the Morris screening method was used to qualitatively identify the parameters＇ sensitivity, and then ten parameters were selected to quantify the sensitivity indices. Subsequently, the RSMSobol method was used to quantify the sensitivity, i.e., the first-order and total sensitivity indices based on the response surface model （RSM） were calculated. The RSMSobol method can not only quantify the sensitivity, but also reduce the computational cost, with good accuracy compared to the classical approaches. This approach will be effective and reliable in the global sensitivity analysis of a complex large-scale distributed hydrological model.

关键词： Xin'anjiang model," global sensitivity analysis parameter identification meta-modeling approach," response surface model

Investigation on the relationship between hydraulic loss and vortex evolution in pump mode of a pump-turbine

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Journal of Hydrodynamics 2022年第4期34卷 555-569页

作者： Yong-lin Qin De-you Li Hong-jie Wang zhan-sheng Liu Xian-zhu Wei Xiao-hang Wang School of Energy Science and Engineering Harbin Institute of TechnologyHarbin 150001China State Key Laboratory of Hydro-Power Equipment Harbin Institute of Large Electrical MachineryHarbin 150040China

Hydraulic loss and vorticity are two most common methods in analyzing the flow characteristics in hydro-machine,i.e.,centrifugal pump,Francis turbine,*** the relationship and correlation between hydraulic loss and vortex evolution are not uncovered *** this study,hydraulic loss is regarded as the combination of dissipation effect and transportation effect in flow ***,vorticityωcan be decomposed into two parts,namely the Liutex partω_(R),the shear partωs,of whichω_(R)is regarded as the third-generation vortex identification method for its precise and rigorous definition of local rigid rotation part of *** on the dimensional analysis,two new physical quantities related to vorticity(ω,ω_(R)andωS),namely enstrophyΩ,vorticity transport intensity T are adopted to express the energy characteristic in vortex evolution ***,operating points at pump mode of an ultra-high head reversible pump-turbine are selected as the research object and the numerical results calculated using SST k-ωturbulence model are consistent well with the experimental *** correlation coefficient is adopted to evaluate the correlation between hydraulic loss and vortex evolution in main flow *** show that apart from the spiral casing domain,the enstrophy of shear partΩs has very strong correlation with dissipation effect and Liutex transport intensity TR has stronger correlation with transportation effect when compared with other forms of *** correlation between Liutex transport intensity TR and transportation effect is strong in stay/guide vanes(SGVs)while reduce to medium level in runner and draft tube *** spiral casing domain,all forms of vorticity show weak or very weak correlation with transportation *** on the proposed method,we believe that the relationship and correlation between hydraulic loss and vortex evolution in other hydraulic machineries can also be clearly investigated.

关键词： Hydraulic loss enstrophy vorticity transportation pearson correlation coefficient

Histopathological Observation of Lymphocystis Disease and Lymphocystis Disease Virus (LCDV) Detection in Cultured Diseased Sebastes schlegeli

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Journal of Ocean University of China 2007年第4期6卷 378-382页

作者： sheng Xiuzhen zhan Wenbin XU Songjuan CHENG Shunfeng Laboratory of Pathology and lmmunology of Aquatic Animals LMMEC Ocean University of China Qingdao 266003 P. R. China

Lymphocystis nodules occurring in the cultured sting fish Sebastes schlegeli were observed under light and electron microscope. Lymphocystis disease virus (LCDV) in the tissues of diseased fish was detected with indirect immunofluorescence test (IFAT). Results showed that lymphocystis cells had overly irregular nuclei, basophilic intracytoplasmic inclusion bodies with virions budding from the surface, and hyaline capsules outside the cell membrane. Numerous virus particles about 200 nm in diameter scat- tered in the cytoplasm, electron-dense particles 70-80 nm in diameter filled in perinuclear cisterna, and membrane-enveloped parti- cles with electron-dense core of 70-80 nm appeared around cellular nucleus. IFAT using monoclonal antibody against LCDV from Paralichthys olivaceus revealed that specific green fluorescence was present in the cytoplasm of lymphocystis cells, epithelium of stomach, gill lamellae, and muscular fibers under epidermis of S. schlegeli, just as that in the cytoplasm of lymphocystis cells of P. olivaceus, suggesting the presence of LCDV in these tissues.

关键词： sting fish Sebastes schlegeli lymphocystis disease histopathology ultrastructure indirect immunofluorescence test