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De-convolution and De-noising of SAR Based GPS Images Using Hybrid Particle Swarm Optimization

Chinese Journal of Electronics 2023年第1期32卷 166-176页

作者： Rizwan Sadiq Muhammad Bilal Qureshi Muhammad Mohsin Khan dept.of Electrical and Electronic Engineering Koc University dept.of Electrical and Computer Engineering COMSATS University dept.of Radiology and Biomedical Imaging Yale University Sino-Pak Center for Artificial Intelligence (SPCAI) Pak-Austria Fachhochschule:Institute of Applied Sciences and Technology (PAF-IAST)

Synthetic aperture radar(SAR) imaging is an efficient strategy which exploits the properties of microwaves to capture images. A major concern in SAR imaging is the reconstruction of image from back scattered signals in the presence of noise. The reflected signal consist of more noise than the target signal and it is a challenging problem to reduce the noise in the collected signal for better reconstruction of an image. Current studies mostly focus on filtering techniques for noise removal. This can result in an undesirable point spread function causing extreme smearing effect in the desired image. In order to handle this problem, a computational technique, particle swarm optimization(PSO) is used for de-noising purpose and later the target performance is further improved by an amalgamation of Wiener filter.Moreover, to improve the de-noising performance we have exploited the singular value decomposition based morphological filtering. To justify the proposed improvements we have simulated the proposed techniques and results are compared with the conventional existing models. The proposed method revealed considerable decrease in mean square error compared to Wiener filter and PSO techniques. Quantitative analysis of image restoration quality are also presented in comparison with Wiener filter and PSO based on the improvement in signal to noise ratio and peak signal to noise ratio.

关键词： Remote sensing Synthetic aperture radar imaging Wiener filter Particle swarm optimization

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Calculation of Structural Characteristics Evolution during Superplastic Forming of Shells by"SPLEN-O"Application Computer Program Set

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Journal of Materials Science & Technology 2001年第1期17卷 111-112页

作者： E.Chumachenko M.Tsepin A.Tchekine O.Panina dept.of applied mathematics of Moscow institute of Electronics&mathematics MoscowRussia dept.of Technology of Moscow State institute of Steels&Alloys(Technological University) MoscowRussia

The applications of commercial computer program set "SPLEN-O" based on finite elements method (FEM) for the simulation of superplastic forming (SPF) technology of shells are described. The changes in characteristics of ultrafine-grained (UFG) structure during deformation are taken into account in function of viscosity and solving algorithm. Some examples are shown to illustrate the possibilities of FEM simulation for prediction of numerical grain-size data on different SPF stages of shells.

关键词： Structural Characteristics finite elements method superplastic forming computer program FEM simulation

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Artificial lift system optimization using machine learning applications

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Petroleum 2022年第2期8卷 219-226页

作者： Fahad I.Syed Mohammed Alshamsi Amirmasoud K.Dahaghi S.Neghabhan University of Kansas&ADNOC Offshore Dept.of Chemical and Petroleum E…Lawrence66045USA

Currently,in the oil industry,artificial lift optimization(ALO)systems are dealing with different applications including well monitor and control,reservoir management,production optimization,predictive maintenance,artificial lift,and flow assurance,multiphase pumping systems,etc.The scope of this article is to provide a detailed analysis of ALO and predictive pump maintenance applications using machine learning(ML)and artificial intelligence(AI).The oil and gas industry has experienced a lot of improvements that have impacted the businesses and economies associated with the market in recent times.Issues such as unplanned shutdown time and failure of equipment cause a huge impact on many corporations especially with the current fluctuations in hydrocarbon prices.Similarly,advanced modern technologies such as real-time analysis and predictive maintenance are designed to drive ALO systems.This paper covers several applications and techniques in which ML and AI have been applied to optimize hydrocarbon withdrawal from potentially depleted reservoirs that require some external supports to uplift the reservoir fluid from sub surface to surface using artificial lift system.In a nutshell,the applications of AI and ML for the artificial lift selection,their predictive maintenance,equipment malfunctioning detection,etc.using a self-trained system are the main topics of this paper.While reviewing each of these techniques,the workflow is also explained along with the effectiveness of utilizing each application to the current operations.

关键词： Artificial lift optimization Predictive maintenance

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Numerical investigation on arching effect surrounding deep cylindrical shaft during excavation process

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Underground Space 2022年第5期7卷 944-965页

作者： Tanawat Tangjarusritaratorn Yuusuke Miyazaki Yasuo Sawamura Kiyoshi Kishida Makoto Kimura dept.of Urban Management Kyoto Univ.Katsura CampusKyoto 615-8540Japan dept.of Civil and Earth Resources Engineering Kyoto Univ.Katsura CampusKyoto 615-8540Japan

Predicting the inner displacements of deep vertical shafts during the excavation process has been a difficult task considering the geological,structural,and constructional influences.In fact,the two-dimensional(2D)analytical solution based on the retaining wall model remains insufficient for understanding the actual behavior during an excavation.This is because the deformation of vertical shafts becomes complicated due to the unexpected arching effect brought about by the three-dimensional(3D)flexible displacements occurring in the excavation process.Previous analytical solutions only considered the limit equilibrium.Therefore,the present study deals with a 3D soil-structure simulation by considering the displacements of a cylindrical shaft and the mechanical behavior of the surrounding soil as well as the geometry of the cylindrical structure.Moreover,this mechanical behaviors of the surrounding soil and shaft are controlled by the shaft stiffness;hence,the relationships among the shaft stiffness,mechanical behavior of the surrounding soil(in terms of earth pressure coefficient),and shaft displacement were investigated.A cylindrical model,120 m in depth and 20 m in diameter,was positioned at the center of a sand domain,and each excavation step was performed at an interval depth of 20 m.A 3D finite difference method analysis was applied using the modified Cam-Clay(MCC)model to represent the soil behavior.As a result,the present study provides a new normalized lateral earth pressure theory for excavated shafts by considering the 3D arching effect obtained from parametric studies using various levels of shaft stiffness.From a comparison with the analytical solutions of previous studies(Terzaghi,1943a;Prater,1977;Cheng&Hu,2005),it is found that the previous studies underestimated the earth pressure acting on the cylindrical shaft because they did not consider the accurate arching effect.

关键词： Deep cylindrical shaft Excavation analysis Soil mixing wall method Arching effect Finite different method Three-dimensional analysis

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Mapping the multi-hazards risk index for coastal block of Sundarban,India using AHP and machine learning algorithms

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Tropical Cyclone Research and Review 2022年第4期11卷 225-243页

作者： Pintu Mandal Arabinda Maiti Sayantani Paul Subhasis Bhattacharya Suman Paul dept.of Geography Sidho-Kanho-Birsha UniversityPuruliaW.B.India dept.of Geography Vidyasagar UniversityMedinipurW.B.India dept.of Economics Calcutta UniversityKolkataW.B.India dept.of Economics Sidho-Kanho-Birsha UniversityPuruliaW.B.India

Global climate change,climate extremes,and overuse of natural resources are all major contributors to the risk brought on by cyclones.In I West Bengal state of India,the Pathar Pratima Block frequently experiences a variety of risks that result in significant loss of life and livelihood.In order to govern coastal society,it is crucial to measure and map the multi-hazards risk status.To depict the multi-hazards vulnerability and risk status,no cutting-edge models are currently being applied.Predicting distinct physical vulnerabilities is possible using a variety of cutting-edge machine learning techniques.This study set out to precisely describe multi-hazard risk using powerful machine learning methods.This study involved the use of Analytic Hierarchical Analysis and two cutting-edge machine-learning algorithms-Random Forest and Artificial Neural Network,which are yet underutilized in this area.The multi-hazards risk was determined by taking into account six criteria.The southern and eastern regions of the research area are clearly identified by the multi-hazards risk maps as having high to extremely high hazards risk levels.Cyclonic hazards and embankment breaching are the main dominant factors among the multi-hazards.The machine learning approach is the most accurate model for mapping the multi-hazards risk where the ROC result of Random forest and artificial neural network is more than the conventional method AHP.Here RF is the most validated model than the other two.The effectiveness,root mean square error,true skill statistics,Friedman and Wilcoxon rank test,and area under the curve of receiver operating characteristic tests were used to evaluate the prediction capacity of newly constructed models.The RMSE values of 0.24 and 0.26,TSS values of 0.82 and 0.73,and AUC values of 88.20%and 89.10%as produced by RF and ANN models,respectively,were all excellent.

关键词： Cyclone Livelihood Multi-hazards Risk Machine-learning

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Early estimation of the number of hidden HIV infected subjects: An extended Kalman filter approach

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Infectious Disease Modelling 2023年第2期8卷 341-355页

作者： Paolo Di Giamberardino Daniela Iacoviello dept.of Computer Control and Management EngineeringSapienzaUniversity of RomeVia Ariosto 2500185RomeItaly

In the last decades several epidemic emergencies have been affecting the world,influencing the social relationships,the economics and the habits.In particular,starting in the early 080,the Acquired Immunodeficiency Syndrome,AIDS,is representing one of the most worrying sanitary emergency,that has caused up to now more than 25 million of dead patients.The infection is caused by the Human Immunodeficiency Virus,HIV,that may be transmitted by body fluids;therefore with wise behaviours the epidemic spread could rapidly be contained.This sanitary emergency is peculiar for the long incubation time:it can reach even 10 years,a long period in which the individual can unconsciously infect other subjects.The identification of the number of infected unaware people,mandatory to define suitable containment measures,is here obtained by using the extended Kalman filter applied to a noisy model in which,reasonably,only the number of infected diagnosed patients is available.Numerical simulations and real data analysis support the effectiveness of the approach.

关键词： Epidemic modeling Infection spread HIV-AIDS Extended Kalman filter

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Global finite-time stabilization design for a class of high-order uncertain nonlinear systems

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Journal of Harbin Institute of Technology(New Series) 2012年第3期19卷 77-80页

作者：孟桂芝马克茂张佳为 Control and Simulation Center Harbin Institute of Technology dept.of applied mathematics Harbin University of Science and Technology

The problem of finite-time stabilization for uncertain nonlinear systems is investigated.It is proved that a class of high-order nonlinear systems in the lower-triangular form is globally stabilized via non-Lipschitz continuous state feedback.By using the finite-time Lyapunov stability theorem and the method of non-smooth feedback design,a recursive design procedure is provided,which guarantees the finite-time stability of the closed-loop system.The simulation results show the effectiveness of the theoretical results.

关键词： finite-time stability continuous state feedback non-smooth control high-order nonlinear system

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An immuno-epidemiological model for transient immune protection:A case study for viral respiratory infections

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Infectious Disease Modelling 2023年第3期8卷 855-864页

作者： A.Hoyer-Leitzel S.M.Iams A.J.Haslam-Hyde M.L.Zeeman N.H.Fefferman Department of mathematics and Statistics Mount Holyoke College50 College StSouth HadleyMA01075USA John A.Paulson School of Engineering and applied Sciences Harvard UniversityUSA Department of mathematics and Statistics Boston UniversityUSA Department of mathematics Bowdoin CollegeUSA dept.of mathematics&dept.of Ecology and Evolutionary Biology&NIMBioS University of TennesseeKnoxvilleUSA

The dynamics of infectious disease in a population critically involves both within-host pathogen replication and between host pathogen transmission.While modeling efforts have recently explored how within-host dynamics contribute to shaping population transmission,fewer have explored how ongoing circulation of an epidemic infectious disease can impact within-host immunological dynamics.We present a simple,influenza-inspired model that explores the potential for re-exposure during a single,ongoing outbreak to shape individual immune response and epidemiological potential in non-trivial ways.We show how even a simplified system can exhibit complex ongoing dy-namics and sensitive thresholds in behavior.We also find epidemiological stochasticity likely plays a critical role in reinfection or in the maintenance of individual immunological protection over time.

关键词： Flow-kick dynamics Immuno-epidemiology Viral-immune mathematical model Immune boosting Priming number

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Preparation of superabsorbent by graft copolymerization of acrylic acid onto corn starch using K_2S_2O_8 and rare earths as initiators

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Journal of Harbin Institute of Technology(New Series) 2008年第6期15卷 831-834页

作者：白永平李卫东冯立群赵超 dept.of applied Chemistry Harbin Institute of Technology

K2S2O8 and rare earths(RE)were used as initiators to prepare superabsorbents by graft copolymerization of acrylic acid(AA)onto corn starch.The effects of monomer concentration,initiator K2S2O8 concentration,cross-linker concentration,reaction temperature and the concentration ratio of RE and K2S2O8 on the graft copolymerization were studied in terms of the water absorption capacity of superabsorbents.Results indicate that the optimum conditions obtained for the grafting of AA onto 5g starch are as follows:AA of 75.773 g/L,K2S2O8 of 0.437 g/L,RE of 0.874 g/L,cross-linker of 0.381 g/L and temperature of 70 ℃.The maximum water absorption capacity obtained is 740 g/g.The new method of graft polymerization is easily proceeded and controlled.The graft copolymers were characterized by infra-red spectroscopy,scanning electron microscopy and TG.Results characterized by IR and SEM give strong evidence for grafting of AA onto corn starch,and those characterized by TG reveal that the grafting of AA improves the thermostability of corn starch.

关键词：超吸收剂共聚合淀粉丙烯酸

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Crystallization process of 2-chloro-4,6-diaminoresorcinol

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Journal of Harbin Institute of Technology(New Series) 2009年第4期16卷 532-536页

作者：宋元军黄玉东林宏黎俊王卓 dept.of applied Chemistry Harbin Institute of Technology

In order to get 2-chloro-4,6-dinitroresocinol(CDNR) with high purity,which influences the synthesis of 4,6-diaminoresorcinol dihydrochloride,the solubility of CDNR in various solvents was measured by laser method and ethanol was chosen as the solvent.The recrystallization process of CDNR was investigated and crystallizing parameters such as cooling rate,temperature and time were discussed.Experimental results show that the time and temperature of crystallization greatly affect the yield and a higher yield can be received at-8 ℃ for 5 h.Slow cooling rate is helpful to the crystallization of CDNR,and the mechanical stirring or ultrasonic treatment can increase the yield and the purity of CDNR.

关键词：结晶过程间苯二酚二氨基氯时间参数结晶温度冷却速度结晶速率

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