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Reconstruction and transmission of astronomical image based on compressed sensing

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Journal of Systems Engineering and Electronics 2016年第3期27卷 680-690页

作者： Xiaoping Shi Jie Zhang Control and Simulation Center Harbin Institute of Technology

In the process of image transmission, the famous JPEG and JPEG-2000 compression methods need more transmission time as it is difficult for them to compress the image with a low compression rate. Recently the compressed sensing（CS） theory was proposed, which has earned great concern as it can compress an image with a low compression rate, meanwhile the original image can be perfectly reconstructed from only a few compressed data. The CS theory is used to transmit the high resolution astronomical image and build the simulation environment where there is communication between the satellite and the Earth. Number experimental results show that the CS theory can effectively reduce the image transmission and reconstruction time. Even with a very low compression rate, it still can recover a higher quality astronomical image than JPEG and JPEG-2000 compression methods.

关键词： transmission time compression rate compressed sensing（CS） high resolution astronomical image

Super-resolution reconstruction of astronomical images using time-scale adaptive normalized convolution

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Chinese Journal of Aeronautics 2018年第8期31卷 1752-1763页

作者： Rui GUO Xiaoping Shi Yi ZHU Ting YU Control and Simulation Center Harbin Institute of Technology Harbin 150080 China Tianjin Branch of China Petroleum Pipeline Engineering Company Limited Tianjin 300457 China

In this work, we describe a new multiframe Super-Resolution（SR） framework based on time-scale adaptive Normalized Convolution（NC）, and apply it to astronomical images. The method mainly uses the conceptual basis of NC where each neighborhood of a signal is expressed in terms of the corresponding subspace expanded by the chosen polynomial basis function. Instead of the conventional NC, the introduced spatially adaptive filtering kernel is utilized as the applicability function of shape-adaptive NC, which fits the local image structure information including shape and orientation. This makes it possible to obtain image patches with the same modality,which are collected for polynomial expansion to maximize the signal-to-noise ratio and suppress aliasing artifacts across lines and edges. The robust signal certainty takes the confidence value at each point into account before a local polynomial expansion to minimize the influence of outliers.Finally, the temporal scale applicability is considered to omit accurate motion estimation since it is easy to result in annoying registration errors in real astronomical applications. Excellent SR reconstruction capability of the time-scale adaptive NC is demonstrated through fundamental experiments on both synthetic images and real astronomical images when compared with other SR reconstruction methods.

关键词： Astronomical image processing Motion estimation Normalized Convolution（NC） Polynomial expansion Signal-to-noise ratio Super-Resolution （SR）reconstruction

Astronomical image restoration using variational Bayesian blind deconvolution

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Journal of Systems Engineering and Electronics 2017年第6期28卷 1236-1247页

作者： Xiaoping Shi Rui Guo Yi Zhu Zicai Wang Control and Simulation Center Harbin Institute of Technology Harbin 150080 China

An algorithm is presented for image prior combinations based blind deconvolution and applied to astronomical images.Using a hierarchical Bayesian framework, the unknown original image and all required algorithmic parameters are estimated simultaneously. Through utilization of variational Bayesian analysis,approximations of the posterior distributions on each unknown are obtained by minimizing the Kullback-Leibler(KL) distance, thus providing uncertainties of the estimates during the restoration process. Experimental results on both synthetic images and real astronomical images demonstrate that the proposed approaches compare favorably to other state-of-the-art reconstruction methods.

关键词： blind deconvolution variational Bayesian model com bination astronomical image processing

Dual-quaternion-based modeling and control for motion tracking of a tumbling target

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Journal of Systems Engineering and Electronics 2019年第5期30卷 985-994页

作者： PENG Xuan shi xiaoping GONG Yupeng Control and Simulation Center Harbin Institute of TechnologyHarbin 150001China Research Center of Satellite Technology Harbin Institute of TechnologyHarbin 150001China

This paper investigates the problem of controlling a chasing spacecraft(chaser)to track and rendezvous with an uncontrolled target.Based on the actual situation,the torque-free motion of an axisymmetric prolate rigid body is employed to represent the short-term attitude motion of the tumbling target.By taking advantage of the dual quaternion’s compact and efficient description of the general rigid motion,the coupled and integrated model of the 6-degree-of-freedom(6-DOF)relative motion between the chaser and the tumbling target is derived in the chaser’s body fixed frame after taking full consideration of coordinate transformation.Based on the logarithm of dual quaternion,a sliding mode control(SMC)law based on the exponential reaching law and the continuous relay function is brought forward to address the problem of synchronization control of the 6-DOF relative motion.Simulation results illustrate the effectiveness of the proposed method.

关键词： tumbling target dual-quaternion coupled dynamics relative motion

A Mixed-Depth Visual Rendering Method for Bleeding Simulation

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IEEE/CAA Journal of Automatica Sinica 2019年第4期6卷 917-925页

作者： Wen shi Peter xiaoping Liu Minhua Zheng the School of Mechanical Electronic and Control EngineeringBeijing Jiaotong UniversityBeijing 100044China IEEE the Department of Systems and Computer Engineering Carleton UniversityOttawaON K1S 5B6Canada

The visual fidelity of bleeding simulation in a surgical simulator is critical since it will affect not only the degree of visual realism,but also the user’s medical judgment and treatment in real-life settings.The conventional marching cubes surface rendering algorithm provides excellent visual effect in rendering gushing blood,however,it is insufficient for blood flow,which is very common in surgical procedures,since in this case the rendered surface and depth textures of blood are rough.In this paper,we propose a new method called the mixed depth rendering for rendering blood flow in surgical simulation.A smooth height field is created to minimize the height difference between neighboring particles on the bleeding surface.The color and transparency of each bleeding area are determined by the number of bleeding particles,which is consistent with the real visual effect.In addition,there is no much extra computational cost.The rendering of blood flow in a variety of surgical scenarios shows that visual feedback is much improved.The proposed mixed depth rendering method is also used in a neurosurgery simulator that we developed.

关键词： Bleeding simulation bleeding suction rendering algorithm marching cubes mixed depth rendering

Integrated modeling of spacecraft relative motion dynamics using dual quaternion

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Journal of Systems Engineering and Electronics 2018年第2期29卷 367-377页

作者： PENG Xuan shi xiaoping GONG Yupeng Control and Simulation Center Harbin Institute of Technology Research Center of Satellite Technology Harbin Institute of Technology

To realize high accurate control of relative position and attitude between two spacecrafts, the coupling between position and attitude must be fully considered and a more precise model should be established. This paper breaks the traditional divide and conquer idea, and uses a mathematical tool, namely dual quaternion to establish the integrated 6 degree-of-freedom(6-DOF) model of relative position and attitude, which describes the coupled relative motion in a compact and efficient form and needs less information of the target. Considering the complex operation rules and the unclarity of the current relative motion model in dual quaternion, necessary mathematical foundations are given at first, followed by clear and detailed modeling process and analysis. Finally a generalized proportion-derivative(PD) controller law is designed. The simulation results show that based on the integrated model established by dual quaternion, this control law can achieve a high control accuracy of relative motion.

关键词： relative motion dual quaternion position and attitude coupling integrated modeling

(DarkAI)Mapping the large-scale density field of dark matter using artificial intelligence

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Science China(Physics,Mechanics & Astronomy) 2024年第1期67卷 143-159页

作者： Zitong Wang Feng shi Xiaohu Yang Qingyang Li Yanming Liu xiaoping Li School of Aerospace Science and Technology Xidian UniversityXi’an 710126China Department of Astronomy School of Physics and Astronomyand Shanghai Key Laboratory for Particle Physics and CosmologyShanghai Jiao Tong UniversityShanghai 200240China Tsung-Dao Lee Institute and Key Laboratory for Particle Physics Astrophysics and CosmologyMinistry of EducationShanghai Jiao Tong UniversityShanghai 200240China Institute for Astronomy University of EdinburghRoyal ObservatoryEdinburgh EH93HJUnited Kingdom

Herein,we present a deep-learning technique for reconstructing the dark-matter density field from the redshift-space distribution of dark-matter halos.We built a UNet-architecture neural network and trained it using the COmoving Lagrangian Acceleration fast simulation,which is an approximation of the N-body simulation with 5123 particles in a box size of 500 h^(-1)Mpc.Further,we tested the resulting UNet model not only with training-like test samples but also with standard N-body simulations,such as the Jiutian simulation with 61443particles in a box size of 1000 h^(-1)Mpc and the ELUCID simulation,which has a different cosmology.The real-space dark-matter density fields in the three simulations can be reconstructed reliably with only a small reduction of the cross-correlation power spectrum at 1%and 10%levels at k=0.1 and 0.3 h Mpc-1,respectively.The reconstruction clearly helps to correct for redshift-space distortions and is unaffected by the different cosmologies between the training(Planck2018)and test samples(WMAP5).Furthermore,we tested the application of the UNet-reconstructed density field to obtain the velocity&tidal field and found that this approach provides better results compared with the traditional approach based on the linear bias model,showing a 12.2%improvement in the correlation slope and a 21.1%reduction in the scatter between the predicted and true velocities.Thus,our method is highly efficient and has excellent extrapolation reliability beyond the training set.This provides an ideal solution for determining the three-dimensional underlying density field from the plentiful galaxy survey data.

关键词： dark matter large-scale structure cosmology

Synthesis,in vitro antibacterial and antifungal evaluation of novel 1,3,4-oxadiazole thioether derivatives bearing the 6-fluoroquinazolinylpiperidinyl moiety

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Chinese Chemical Letters 2020年第2期31卷 434-438页

作者： Jun shi Na Luo Muhan Ding xiaoping Bao State Key Laboratory Breeding Base of Green Pesticide and Agricultural Bioengineering Key Laboratory of Green Pesticide and Agricultural BioengineeringMinistry of EducationCenter for Research and Development of Fine ChemicalsGuizhou UniversityGuiyang 550025China

A series of structurally novel 1,3,4-oxadiazole thioether derivatives(6a-6z) containing a 6-fluoroquinazolinylpiperidinyl moiety were designed and synthesized using pharmacophore hybrid approach,and their structures were fully characterized by ^1H NMR,^(13)C NMR and HRMS spectra.Among them,the structure of compound 6 d was further corroborated via single-crystal X-ray diffraction analysis.In vitro antibacterial bioassays showed that compounds 6 a,6 g,6 u and 6 v possessed EC_(50) values of 30.4,30.6,27.5 and 26.0 μg/mL against phytopathogenic bacterium Xanthomonas oryzae pv.oryzae,respectively,which were significantly superior to that of commercially-available bactericide Bismerthiazol(85.1 μg/mL).Moreover,in vitro antifungal bioassays indicated that seven compounds demonstrated broad-spectrum fungicidal acitivties against six types of phytopathogenic fungi at 50 μg/mL.The present work showed the potential of 1,3,4-oxadiazole thioether derivatives carrying a 6-fluoroquinazolinylpiperidinyl moiety as effective antimicrobial agents for crop protection,deserving further investigations in the future.

关键词： 1,3,4-Oxadiazole thioether Fluoroquinazolinylpiperidinyl Synthesis Antibacterial activity Antifungal activity

Protein amplification technology:New advances in human prion disease diagnosis

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Biosafety and Health 2021年第6期3卷 325-332页

作者： Jingxing Wu Dongdong Chen Qi shi xiaoping Dong State Key Laboratory for Infectious Disease Prevention and Control National Institute for Viral Disease Control and PreventionChinese Center for Disease Control and PreventionBeijing 102206China

Early and accurate diagnosis of human prion diseases is a long-standing difficulty.Currently,the definitive diagnosis of human prion diseases relies on pathognomonic histological features or PrPSc detection of patients'brain tissue biopsy or autopsy samples,which is not feasible in most cases.Therefore,clinical diagnosis mainly relies on the combinations of the patient’s clinical symptoms.MRI and EEG are used to check for brain damage and detect surrogate markers such as the 14-3-3 protein in Cerebrospinal fluid(CSF),but this is often challenging.In recent years,the development of in vitro cell-free conversion techniques,such as technologies protein misfolding cyclic amplification(PMCA)and real-time quaking-induced conversion(RT-QuIC),have extensively promoted the diagnosis of human prion diseases.PMCA has high diagnostic accuracy in the blood,CSF,and urine samples of variant creutzfeldt–jakob disease(vCJD)patients.Again,RT-QuIC has high diagnostic accuracy for cerebrospinal fluid,olfactory mucosa,and skin samples of sporadic Creutzfeldt Jakob Disease(sCJD)patients.Applying these two technologies is of great significance to the early clinical diagnosis of human prion diseases and the reduction of blood-borne and iatrogenic transmission of prion.

关键词： PMCA RT‐QuIC Human prion diseases