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Hyperspectral anomaly detection:a performance comparison of existing techniques

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International Journal of Digital Earth 2022年第1期15卷 2078-2125页

作者： Noman Raza Shah Abdur Rahman M.Maud Farrukh Aziz Bhatti Muhammad khizer Ali Khurram Khurshid Moazam Maqsood Muhammad Amin iVISION Lab Electrical Engineering DepartmentInstitute of Space TechnologyIslamabadPakistan AI Enabling Technologies Lab Center of Excellence in Artificial IntelligenceBahria UniversityIslamabadPakistan Department of Electrical and Computer Engineering Pak-Austria Fachhochschule:Institute of Applied Sciences and TechnologyHaripurPakistan Avionics Engineering Department Institute of Space TechnologyIslamabadPakistan

Anomaly detection in Hyperspectral Imagery(HSI)has received considerable attention because of its potential application in several *** anomaly detection algorithms for HSI have been proposed in the literature;however,due to the use of different datasets in previous studies,an extensive performance comparison of these algorithms is *** this paper,an overview of the current state of research in hyperspectral anomaly detection is presented by broadly dividing all the previously proposed algorithms into eight different *** addition,this paper presents the most comprehensive comparative analysis to-date in hyperspectral anomaly detection by evaluating 22 algorithms on 17 different publicly available *** indicate that attribute and edge-preserving filtering-based detection(AED),local summation anomaly detection based on collaborative representation and inverse distance weight(LSAD-CR-IDW)and local summation unsupervised nearest regularized subspace with an outlier removal anomaly detector(LSUNRSORAD)perform better as indicated by the mean and median values of area under the receiver operating characteristic(ROC)***,this paper studies the effect of various dimensionality reduction techniques on anomaly *** indicate that reducing the number of components to around 20 improves the performance;however,any further decrease deteriorates the performance.

关键词： Anomaly detection algorithms hyperspectral imagery deep learning dimensionality reduction

Monkeypox:A comprehensive review of a multifaceted virus

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Infectious Medicine 2023年第2期2卷 74-88页

作者： Randa Elsheikh Abdelrahman M.Makram Tamilarasy Vasanthakumaran Shubham Tomar khizer Shamim Nguyen Dong Tranh Sara S.Elsheikh Nguyen Thanh Van Nguyen Tien Huy Deanery of Biomedical Sciences at Edinburgh Medical School University of EdinburghEdinburgh EH105HFUnited Kingdom Online Research Club(http://***) Nagasaki 852-8523Japan School of Public Health Imperial College LondonLondon SW72BXUnited Kingdom Global Clinical Scholars Research Training Harvard Medical SchoolBostonMA 02115USA Tata Memorial Hospital Varanasi 400012India DataQ Health Karachi 75100Pakistan Department of Infection Control Binh Dinh Provincial General HospitalBinh Dinh 55000Vietnam Faculty of Medicine Zagazig UniversityZagazig 44519Egypt School of Tropical Medicine and Global Health Nagasaki UniversityNagasaki 852-8523Japan

In May 2022,the world witnessed the re-emergence of the zoonotic disease *** this was not the first epidemic of this disease,what differentiated the outbreak was the rapid global spread and increase of cases,which led the WHO to declare monkeypox a global health *** the disease spreads mainly through inadequately cooked meat of various rodent species,this virus also shows droplet,respiratory,sexual,and even vertical *** further multiplies in lymphoproliferative organs and presents with a classical smallpox-like rash,fever,headache,and muscle *** is confirmed with a polymerase-chain-reaction test and is managed largely supportively with possible usage of some antivirals and ***,some pre-exposure and postexposure prophylactic vaccines have been *** paper aims to conduct an in-depth review of the historical epidemics,transmission,pathophysiology,clinical presentation,and management of the monkeypox disease.

关键词： Monkeypox Orthopoxvirus Outbreak Smallpox

Angular velocity dynamics identification of small unmanned helicopter using fuzzy model

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Journal of Beijing Institute of Technology 2014年第4期23卷 527-533页

作者： khizer Arbab Nighat 戴亚平 SYED Amjad Ali 许向阳 School of Automation Beijing Institute of Technology Mehran University of Engineering and Technology JamshoroSindhPakistan School of Mechatronics Beijing Institute of Technology

Attitude identification method for unmanned helicopter based on fuzzy model at hovering is presented. The dynamical attitude model is considered as basis for attitude control and it is very complex. To reduce the complexity of model, nonlinear model of unmanned helicopter with unknown parameters are to be determined by fuzzy system first and then derivative based gradient method is used to identify unknown parameters of model. Gradient method is used due to ability that fuzzy system is not necessarily to be linear in parameters, therefore all fuzzy sets for input and output can be adjusted. The validity of the proposed model was verified using experimental data obtained by the commercially available flight simulator X-Plane. The simulation results showed high accuracy of the modeling method and attitude dynamics data matched well with experimental data.

关键词： small unmanned helicopter ( SUH ) identification Takagi-Sugeno ( TS ) fuzzy model attitude model gradient method

Input series out putparallel based multi-modular boost half bridge DC-DC converter with a dynamic control scheme

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Journal of Beijing Institute of Technology 2014年第4期23卷 519-526页

作者： SOOMRO Amir Mahmood SYED Amjad Ali khizer Arbab Nighat 廖晓钟 MANZOOR Muhammad Farhan School of Automation Beijing Institute of Technology Mehran University of Engineering and Technology JamshoroSindhPakistan School of Mechatronics Beijing Institute of Technology

Multi-modular system plays an important role in power system architecture because low voltage and low power converters can be connected in any combination parallel or series at input/ output side in order to obtained any given power system specifications. Multi-modular boost haft bridge DC-DC converter in the configuration of input series output parallel has been investigated in this paper. The boost half bridge DC-DC converters are connected in input series output parallel con- figuration in order to achieve equal input voltage sharing and output current sharing between the con- verters. This can be achieved with the help of dynamic control scheme which consists of two loops, a voltage loop and a current loop, for each module. Dynamic behavior of multi-modular converter configuration has been observe by varying the load condition. Moreover, the results obtained through multi-modular converter describe that the system has good dynamic and steady state response. Al- though two converter modules are focused in this paper but it can be modified to any number of modules.

关键词： boost haft bridge ( BHB ) input series output parallel ( ISOP ) input voltage sharing(IVS) multi-modular output current sharing (OCS)

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钻削硬岩层PDC刀具磨损分析

钻削硬岩层PDC刀具磨损分析

作者： Hafiz khizer Bin Talib 山东大学

学位级别：硕士

预测钻头刀片的磨损,对石油公司的钻探效率提高,成本和钻探周期降低,是非常重要的。该问题已经通过在钻探形成间隔处评估钻头的磨损率来解决。尽管此技术有时可以很好地说明钻头的磨损情况,但许多现象(例如钻头结球和钻头的高振动)可能... 详细信息

预测钻头刀片的磨损,对石油公司的钻探效率提高,成本和钻探周期降低,是非常重要的。该问题已经通过在钻探形成间隔处评估钻头的磨损率来解决。尽管此技术有时可以很好地说明钻头的磨损情况,但许多现象(例如钻头结球和钻头的高振动)可能会产生误导性的结果,从而影响这些技术的可靠性。因此,有必要通过建模和理论方法来开发一种有效的钻头磨耗率预测工具。本文结合了 PDC钻头磨损评估的案例研究和无因次钻孔参数方法,将其作为监测PDC钻头磨损的指示工具。将结果与钻头的定性齿磨损指数进行了比较,并在有限的情况下得到了一致的结论。案例研究不包括形成钻头的材料的机械性能,因此需要一个磨损模型来将钻孔参数与形成钻头的材料的机械性能结合起来。对多晶金刚石压片机和岩石进行了仿真建模,以研究两种不同的情况。首先是对硬岩切割进行有限元分析。为了优化使用多晶金刚石复合片(PDC)刀具的钻孔过程,了解切削工具与岩石之间的相互作用非常重要。为了解释刀具岩石接触的行为,岩石破裂和破碎,使用了 ANSYS2D-AUTODYN。对二维单PDC刀具和岩石进行建模,以模拟正交切削过程,并观察花岗岩和玄武岩岩石上的切削深度(DOC)和后倾角等不同参数的结果。第二种情况是钻硬岩时单多晶金刚石复合片(PDC)钻头刀具的磨损率。该项目旨在研究刀具后倾角和刀具尺寸对硬地层中PDC刀具磨损率的影响。因为地层的磨蚀性和冲击载荷损坏导致刀具过度磨损,常规的PDC钻头经常在坚硬的地层中失效。该研究的重点是使用13毫米和16毫米PDC刀具的单刀测试,以研究后倾角和刀形对硬质合金(花岗岩)的影响。在恒定的作用力和速度下模拟钻孔操作。PDC刀具的理论基础是根据刀具-岩石相互作用模型和Merchant的正交切削模型进行研究的。使用基于岩石力学的ANSYS,使用单个PDC刀具进行岩石破碎的3D模拟模型,以分析刀具下方的应力。使用磨损模型分析了后倾角和PDC刀具尺寸对刀具磨损率的影响。

关键词：多晶金刚石复合片岩石切割有限元法破碎切削力磨损

Seismic and stress qualification of LMFR fuel rod and simple method for the determination of LBE added mass effect

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Nuclear Science and Techniques 2020年第1期31卷 42-56页

作者： M.khizer Jian-Wei Chen Guo-Wei Yang Qing-Sheng Wu Yong Song Yong Zhang Key Laboratory of Neutronics and Radiation Safety Institute of NuclearEnergy Safety TechnologyChinese Academy of SciencesHefei 230031China University of Science and Technology of China Hefei 230027China

In this study, two different designs of liquid metal fast reactor(LMFR) fuel rods wire-wrapped and nonwire-wrapped(bare) are compared with respect to different parameters as a means of considering the optimum fuel design. Nuclear seismic rules require that systems and components that are important for safety must be capable of bearing earthquake effects, and that their integrity and functionality should be guaranteed. Mode shapes, natural frequencies, stresses on cladding, and seismic aspects are considered for comparison using ANSYS. Modal analysis is compared in a vacuum and in lead–bismuth eutectic(LBE) using potential flow theory by considering the added mass effect. A simple and accurate approach is suggested for the determination of the LBE added mass effect and is verified by a manually calculated added mass, which further proved the usefulness of potential flow theory for the accurate estimation of the added mass effect. The verification of the hydrodynamic function(τ) over the entire frequency range further validated the finite element method(FEM) modal analysis results. Stresses obtained for fuel rods against different loading combinations revealed that they were within the allowable limits with maximum stress ratios of 0.25(bare) and 0.74(wire-wrapped). In order to verify the structural integrity of cladding tubes, stresses along the cladding length were determined during different transients and were also calculated manually for static pressure. The manual calculations could be roughly compared with the ANSYS results, and the two showed a close agreement. Contact analysis methodology was selected,and the most appropriate analysis options were suggested for establishing contact between the wire and cladding for the wire-wrapped design grid independence analysis,which proved the accuracy of the results, confirmed the selection of the appropriate procedure, and validated the use of the ANSYS mechanical APDL code for LMFR fuel rod analysis. The results provi

关键词： LMFR Fuel rod Added mass Seismic analysis Contact analysis

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智能水下机器人全局及局部路径规划技术研究

智能水下机器人全局及局部路径规划技术研究

作者：哈泽尔（khizer Naveed）北京理工大学

学位级别：硕士

路径规划技术是智能水下机器人（Autonomous Underwater Vehicle,简称AUV）的关键技术之一,在一定程度上它标志着水下机器人智能水平的高低。路径规划的目的、不同的运动规划必须考虑动力学,是找到一个动的最优路径,用最少的时间以及完... 详细信息

路径规划技术是智能水下机器人（Autonomous Underwater Vehicle,简称AUV）的关键技术之一,在一定程度上它标志着水下机器人智能水平的高低。路径规划的目的、不同的运动规划必须考虑动力学,是找到一个动的最优路径,用最少的时间以及完全的环境模型。我们讨论了这些最成功的机器人三维路径规划算法的基本原理,近年来已经发展起来,集中在可应用于空中机器人、地面机器人和水下机器人的普遍适用的算法上。这论文对大范围海洋有流环境下智能水下机器人的路径规划技术进行了系统深入的研究,主要包括以下几个方面的内容:本文首先介绍了机器人以及智能水下机器人的发展情况,分析了智能水下机器人的国内外的研究动态和发展趋势,详细介绍了课题的背景和主要内容。其次简要介绍了机器人路径规划技术,包括路径规划的定义、分类、相关问题、几种典型的路径规划方法以及最新的研究动态等。在分析大范围海洋环境下路径规划的复杂性以及总结以前的路径规划算法的基础上,提出了一整套从全局到局部的路径规划算法。最后,本文分别详细介绍了全局路径规划和局部路径规划两个算法:基于分层模型的遗传模拟退火算法路径规划和基于雷达法的局部路径规划。包括算法的基本思想、算法实现中的几个关键技术等。本文还给出了两个算法的计算机仿真结果。

关键词：智能水下机器人(AUV) 路径规划分层模型遗传模拟退火算法雷达法

Correction to:Seismic and stress qualification of LMFR fuel rod and simple method for the determination of LBE added mass effect

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Nuclear Science and Techniques 2020年第7期31卷 96-96页

作者： M.khizer Jian-Wei Chen Guo-Wei Yang Qing-Sheng Wu Yong Song Yong Zhang Key Laboratory of Neutronics and Radiation Safety Institute of Nuclear Energy Safety TechnologyChinese Academy of SciencesHefei 230031China University of Science and Technology of China Hefei 230027China

In the original article the authors affiliations are incorrectly *** authors correct affiliations are provided in this correction article.

关键词： correction correctly correct