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Fragile Watermarking of 3D Models Using Genetic Algorithms

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Journal of Electronic Science and Technology 2010年第3期8卷 244-250页

作者： mukesh motwani Rakhi motwani Frederick Harris University of Nevada

This paper describes a novel algorithm for fragile watermarking of 3D models. Fragile watermarking requires detection of even minute intentional changes to the 3D model along with the location of the change. This poses a challenge since inserting random amount of watermark in all the vertices of the model would generally introduce perceptible distortion. The proposed algorithm overcomes this challenge by using genetic algorithm to modify every vertex location in the model so that there is no perceptible distortion. Various experimental results are used to justify the choice of the genetic algorithm design parameters. Experimental results also indicate that the proposed algorithm can accurately detect location of any mesh modification.

关键词： 3D mesh models fragile water- marking genetic algorithms SNR.

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An Eigen-Normal Approach for 3D Mesh Watermarking Using Support Vector Machines

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Journal of Electronic Science and Technology 2010年第3期8卷 237-243页

作者： Rakhi motwani mukesh motwani Frederick Harris Sergiu Dascalu the Computer Science & Engineering Department the University of Nevada

The use of support vector machines （SVM） for watermarking of 3D mesh models is investigated. SVMs have been widely explored for images, audio, and video watermarking but to date the potential of SVMs has not been explored in the 3D watermarking domain. The proposed approach utilizes SVM as a binary classifier for the selection of vertices for watermark embedding. The SVM is trained with feature vectors derived from the angular difference between the eigen normal and surface normals of a 1-ring neighborhood of vertices taken from normalized 3D mesh models. The SVM learns to classify vertices as appropriate or inappropriate candidates for modification in order to accommodate the watermark. Experimental results verify that the proposed algorithm is imperceptible and robust against attacks such as mesh smoothing, cropping and noise addition.

关键词： 3D mesh models support vector machine watermarking.

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Challenges in the Management of a Case of Secondary Abdominal Pregnancy

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Open Journal of Obstetrics and Gynecology 2015年第11期5卷 669-671页

作者： Alpana Singh Vandana Mishra Yashika motwani Pragati Meena UCMS & GTB Hospital New Delhi India

Introduction: Abdominal pregnancy, one of the rare forms of ectopic pregnancy demands a high index of suspicion for its timely diagnosis and intervention so as to prevent both maternal and neonatal complications. We presented a case of secondary abdominal pregnancy which was missed at the first instance at a private centre and came to us with nonspecific abdominal symptoms after an attempted termination of pregnancy by surgical means (dilation and curettage). Case presentation: A 24-year-old third gravida with two live issues at 10-week gestation came to us with complaints of pain lower abdomen, vomiting and inability to pass stool. She gave history of undergoing dilation and curettage (D&C) at a private hospital for termination of pregnancy about 20 days back. After thorough work-up and investigations, the diagnosis of secondary abdominal pregnancy was established and she was taken up for exploratory laparotomy with the removal of fetus with placenta. The patient progressed well with the postoperative period remaining uneventful. Conclusion: Secondary abdominal pregnancy poses as a challenge to clinicians working with limited diagnostic facilities. The condition may be life threatening if not handled meticulously.

关键词： Secondary Abdominal Pregnancy Uterus

Severe Mitral Regurgitation Due to Pacing in Patient Post Aortic Valve Replacement (A Case Report)

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World Journal of Cardiovascular Surgery 2018年第1期8卷 22-27页

作者： Shailendra Kumar motwani Vishnu Datt D. K. Tempe National Board G.B. Pant Hospital New Delhi India Department of Cardiac Anesthesiology and Critical Care G.B. Pant Hospital New Delhi India Department of Cardiac Anesthesiology G.B. Pant Hospital New Delhi India

Epicardial Cardiac pacing may lead to severe Mitral Regurgitation by one of the following mechanisms: 1) Inappropriate Atrioventricular interval. 2) Myocardial ischemia due to fast heart rate may cause transient papillary muscle dysfunction. 3) Right Ventricular apical pacing may lead to Left Ventricular dyssynchrony in the presence of optimal Atrioventricular synchrony. Acute severe Mitral Regurgitation leading to acute severe hemodynamic deterioration is a reported complication of Permanent Pacemaker insertion. Our case demonstrated acute severe MR as a consequence of RV Pacing leading to acute hemodynamic deterioration, which was relieved on withdrawal of pacing. Left Ventricular dyssynchrony can be relieved by reducing the peacemaker rate or changing to biventricular pacing, this reduces the severity of Mitral Regurgitation and improves the hemodynamics due to simultaneous activation of left and right ventricles. This case illustrates the acute and potentially dramatic effects of intra-Left Ventricular dyssynchrony upon Mitral Valve function. Informed consent was obtained from the patient to report the case. Thus right ventricular pacing can cause left ventricular dyssynchrony leading to worsening of Mitral Regurgitation. It is important to pay attention to mode of pacing when evaluating Mitral Regurgitation in patients with Right Ventricular pacemaker and unstable hemodynamics after initiation of pacing.

关键词： Epicardial Pacing Mitral Regurgitation Dyssynchrony Hemodynamics Cardiopulmonary Bypass Atrioventricular Synchrony Atrioventricular Interval

Design of a 10 kV SiC MOSFET-based high-density, high-efficiency, modular medium-voltage power converter

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iEnergy

iEnergy 2022年第1期1卷 100-113页

作者： Slavko Mocevic Jianghui Yu Boran Fan Keyao Sun Yue Xu Joshua Stewart Yu Rong He Song Vladimir Mitrovic Ning Yan Jun Wang Igor Cvetkovic Rolando Burgos Dushan Boroyevich Christina DiMarino Dong Dong Jayesh Kumar motwani Richard Zhang Center for Power Electronics Systems(CPES) Bradley Departement of Electrical and Computer EngineeringVirginia TechBlacksburgVA 24061USA Center for Electromechanics(CEM) The University of Texas at AustinAustinTX 78758USA Department of Electrical and Computer Engineering at the University of Nebraska-Lincoln LincolnNE 68588USA

Simultaneously imposed challenges of highvoltage insulation,high dv/dt,highswitching frequency,fast protection,and thermal management associated with the adoption of 10 kV SiC MOSFET,often pose nearly insurmountable barriers to potential users,undoubtedly hindering their penetration in mediumvoltage(MV)power *** novel technologies such as enhanced gatedriver,auxiliary power supply network,PCB planar dcbus,and highdensity inductor are presented,enabling the SiCbased designs in modular MV converters,overcoming aforementioned ***,purely substituting SiC design instead of Sibased ones in modular MV converters,would expectedly yield only limited ***,to further elevate SiCbased designs,novel highbandwidth control strategies such as switchingcycle control(SCC)and integrated capacitorblocked transistor(ICBT),as well as highperformance/highbandwidth communication network are *** these technologies combined,overcome barriers posed by stateoftheart Si designs and unlock system level benefits such as very high power density,highefficiency,fast dynamic response,unrestricted line frequency operation,and improved power quality,all demonstrated throughout this paper.

关键词： SiC MOSFET modular multilevel converter(MMC) switching-cycle control(SCC) integrated capacitor-blocked transistor(ICBT) PEBB medium-voltage(MV) high density high efficiency

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心肌灌注MR成像收缩期与舒张期采集的比较

国际医学放射学杂志 2012年第3期 269-269页

作者： M.motwani T.A.Fairbairn A.Larghat A.N.Mather J.D.Biglands A.Radjenovic 刘学焕 Multidisciplinary Cardiovascular Research Centre & Leeds Institute of Genetics Health and TherapeuticsUniversity of LeedsLeeds LS2 9JTEngland

目的比较收缩期与舒张期心肌血流量(MBF),并确定两期对可疑冠状动脉疾病(CAD)病人诊断的准确性。材料与方法此项研究经本地区伦理委员会批准,并且所有病人签署知情同意书。接受冠状动脉成像后,40例病人[男27例,平均(64±8)岁]采用1.5TM... 详细信息

目的比较收缩期与舒张期心肌血流量(MBF),并确定两期对可疑冠状动脉疾病(CAD)病人诊断的准确性。材料与方法此项研究经本地区伦理委员会批准,并且所有病人签署知情同意书。接受冠状动脉成像后,40例病人[男27例,平均(64±8)岁]采用1.5TMR设备行应力及静息态MR

关键词：舒张期收缩期 MR 心肌灌注

急性心肌梗死再灌注后的心肌水肿和局部心肌功能之间的关系:MRI研究

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国际医学放射学杂志 2013年第4期 377-377页

作者： A. Kidambi A.N. Mather P. Swoboda M. motwani T.A. Fairbairn J.P. Greenwood 董龙春 Multidisciplinary Cardiovascular Research Centre & Leeds Institute of Genetics Health and Therapeutics University of LeedsGreat George St Leeds LS29JT England

目的比较急性心肌梗死(AMI)病人再灌注后一段时间内的心肌水肿和相应区域的心肌收缩功能的关系。材料与方法本研究经地方伦理委员会批准,所有病人签署知情同意书。39例(男性34例,年龄35～73岁,平均57岁,)ST段抬高AMI病人在经皮冠状动脉... 详细信息

目的比较急性心肌梗死(AMI)病人再灌注后一段时间内的心肌水肿和相应区域的心肌收缩功能的关系。材料与方法本研究经地方伦理委员会批准,所有病人签署知情同意书。39例(男性34例,年龄35～73岁,平均57岁,)ST段抬高AMI病人在经皮冠状动脉介入治疗后的3个时间点行T2加权、标记和晚期钆增强MR成像。测量梗死区、梗死周围区以及远端心肌的环周缩短率、T2加权成像的信号强度和体积。根据梗死周围有无水肿对病人进行分层,梗死周围水肿定义为T2加权信号强度高于远端心肌的2个或更多标准偏差的区域。应用事后Bonferroni校正重复测量方差分析进行数据分析。结果在介入治疗后的3个时间点梗死周围水肿性心肌的收缩力较远端心肌降低,分别为2d(-0.137∶-0.226,P0.05)。梗死周围水肿性心肌在第30天(P=0.02)和第90天(P<0.01)时的收缩力有所改善,这体现在水肿体积的减小和信号强度的降低。收缩力的降低与水肿体积(r=0.30,P=0.01)和标准化的水肿信号强度相关(r=0.28,P<0.01)。在8例完全透壁性梗死病人中,梗死区收缩力在第2～90天之间有所改善(P=0.02)。结论梗死周围心肌收缩力随心肌水肿消退而有所改善。水肿体积和T2加权成像的信号强度与AMI再灌注后心肌功能恢复相关。

关键词：心肌水肿再灌注信号强度加权成像水肿性收缩力心肌功能 MRI

心脏MR成像检测健康吸烟者与非吸烟者冷压实验前后心肌血流变化

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国际医学放射学杂志 2014年第2期 160-160页

作者： T.A.Fairbairn M.motwani A.N.Mather J.D.Biglands A.M.Larghat A.Radjenovic 高子晴 Multidisciplinary Cardiovascular Research Centre &Leeds Institute of Genetics Health and Therapeutics University of Leeds

目的探讨心肌灌注MR成像检测吸烟者与非吸烟者冷压实验(CPT)过程中心肌血流及腺苷负荷前后心肌内皮功能变化的价值。材料与方法本项研究经伦理审查委员

关键词：吸烟者心肌血流量 MR 心脏与非成像检测冷压