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Interleaved high-gain boost converter powered by solar energy using hybrid-based mPP tracking technique

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Clean Energy 2022年第3期6卷 460-475页

作者： s.Nagaraja Rao suresh kumar Anisetty B.m.manjunatha B.m.Kiran kumar V.Praveen kumar s.Pranupa ms Ramaiah University of Applied sciences Department of Electrical EngineeringBangaloreIndia RGm College of Engineering and Technology(Autonomous) NandyalIndia

This paper presents a solar-powered interleaved high-gain boost converter(IHGBC)that increases voltage gain with fewer ripples in the output voltage in comparison to existing DC-DC *** goal of this research is to develop a hybrid-based maximum power point tracking(mPPT)approach with the combination of a flower pollination(FP)algorithm assisted with a perturb&observe(P&O)mPPT approach for solar photovoltaic(sPV)systems integrated with *** ensure effective usage of both FP and P&O algorithms,this study incorporates and validates the hybrid-based mPPT *** proposed solar-powered IHGBC with a hybrid-based mPPT algorithm has been computationally modelled and simulated using mATLAB®and simulink®for both uniform and non-uniform irradiation and analysed for voltage gain,ripples in the output waveforms and convergence *** proposed hybrid-based mPPT is based on a number of flowers that forecast the initial global peak,assisted by P&O in the last stage for faster convergence to attain the maximum power point(mPP).As a result,the hybrid-based mPPT approach alleviates the computational issues encountered in P&O and FP-based mPP *** proposed hybrid mPPT is compared with conventional mPPT for sPV and the results show that the solar-powered IHGBC using a hybrid-based mPPT technique has negligible oscillations of 0.14%with a high-voltage gain of 7.992 and a fast convergence rate of 0.05 seconds compared to individual P&O-based mPPT and FP-based mPPT *** simulation results of the proposed mPPT with IHGBC outperform the conventional mPPT with high-gain converters.

关键词： flower pollination interleaved high-gain boost converter maximum power point tracking technique perturb&observe solar photovoltaic

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水深对动力定位能力的影响

舰船科学技术 2024年第8期46卷 31-36页

作者：刘鹏邹康桂满海上海船舶研究设计院上海201203

在作业过程中,海工船需应对不同水深的海域,而水深对流力和波浪力有影响。针对这一问题,对比5个水深下的环境载荷,并应用二次规划算法求解推进器最大功率利用率,进而分析水深对动力定位能力的影响。结果表明,随着水深的减小,流力和平均... 详细信息

在作业过程中,海工船需应对不同水深的海域,而水深对流力和波浪力有影响。针对这一问题,对比5个水深下的环境载荷,并应用二次规划算法求解推进器最大功率利用率,进而分析水深对动力定位能力的影响。结果表明,随着水深的减小,流力和平均波浪漂移力均呈上升趋势。不同水深下波浪力的差异集中在0.5~1.5 rad/s的波频范围,谐摇会显著增加其对应的艏摇力矩。横浪下,动态载荷的影响已不可忽略,且合力矩的方向由风力主导。环境载荷的变化直接影响了推进器的使用功率。船舶的动力定位能力受首部伸缩推功率的限制,对应100°浪向。当水深为15 m时,该推进器处于满负荷状态;随着水深增至50 m,功率利用百分数降至约60%。因此,对于现有吃水条件,当水深小于20 m,环境载荷和推进器功率骤增,对动力定位的安全性提出了极大挑战;超过40 m后,水深的影响已不再明显,可近似视为无限水深。

关键词：水深动力定位平均波浪漂移力动态载荷

Effect of various physical properties on the reflection coefficients of inhomogeneous waves at the stress-free surface of partially saturated soils induced by obliquely incident fast P-wave

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Journal of Ocean Engineering and science 2022年第3期7卷 225-236页

作者： m.kumari m.s.Barak A.singh m.kumar Department of mathematics M P College for WomenMandi Dabwali125104SirsaHaryanaIndia Department of mathematics Indira Gandhi University MeerpurRewari122503HaryanaIndia Department of mathematics Dr.B R Ambedkar Govt.CollegeDabwali125104SirsaHaryanaIndia

Ghasemzadeh and Abounouri[1]developed a mathematical model of partially saturated soils that is solved using the potential method,which decomposes elastodynamics equations into two standard wave equations,a scalar wave equation for scalar potential and a vector wave equation for vector *** such a medium,four waves exist three longitudinal and one *** fluid phase tortuous path is taken into account in this *** inertial coupling between solid and fluid particles is ***,both open-pore and sealed-pore boundaries are explored to investigate the reflection phenomenon at the surface of partially saturated *** both boundaries,the reflection coefficients of inhomogeneous waves at a partially saturated soil surface are found as a non-singular set of linear *** waves(both reflected and incident)in partially saturated soils are pronounced as inhomogeneous due to viscosity in pore fluids(i.e.,distinct directions of attenuation and propagation).The energy shares of reflected waves are determined using an energy matrix.A numerical example is used to determine the reflection coefficients and the distribution of incident energy among the various reflected *** effect of different physical features on reflection coefficients and incident energy partitioning is illustrated *** conservation of incident energy at the surface of partially saturated soils is mathematically confirmed at all angles of incidence.

关键词： Plane harmonic wave Inhomogeneous Partially saturated soils Reflection coefficients Energy shares

Profile of Autoimmune Polyendocrinopathies at the medical Clinic II of the Abass Ndao Hospital: About 40 Cases

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Open Journal of Internal medicine 2024年第1期14卷 74-82页

作者： michel Assane Ndour Djiby sow mouhamed Dieng Ibrahima mané Diallo Boundia Djiba mélaine Honorine Olympio Julie Borges Preira muriel Diembou Fatou Kiné Gadji Fama Ndiaye El Hadj mamadou moussa Thioye Charles Halim Demba Diédhiou Anna sarr maïmouna Ndour mbaye Abass Ndao Hospital Internal Medicine Department Cheikh Anta Diop University Dakar Senegal Aristide Le Dantec Hospital Internal Medicine Department Cheikh Anta Diop University Dakar Senegal

Introduction: Autoimmune polyendocrinopathies (AP) represent a group of rare concomitant pathologies, making them underdiagnosed. The objective was to study their profile at the medical Clinic II of the Abass Ndao Hospital. Patients and methods: This was an observational, descriptive and analytical study, lasting 24 months, from January 1, 2020 to December 31, 2022. We assessed the epidemiological, clinical and paraclinical characteristics of the patients and classified the APs found. Results: We included 40 patients divided into type III (38 cases) and IV (2 cases). A female predominance was noted with a sex ratio of 0.21. The mean age was 38.6 years. A family history of component diseases of autoimmune polyendocrine syndrome (APs) was found in 62.5%. Goiter (80%) was the main clinical sign present. All 38 patients with IsAP-3 had autoimmune thyroiditis, including 29 cases of Graves’ disease (72.5%) and 9 cases of Hashimoto’s thyroiditis (22.5%). They were associated with either type 1 diabetes (57.9%), Biermer’s disease (21.1%), vitiligo + alopecia (18.4%), lupus (2.6%). The 2 patients with AP-4 had Biermer’s disease associated with either Addison’s disease or type 1 diabetes. management depended on the pathologies present and their possible complications. The immunological phenomena were also controlled. Conclusion: This series is globally similar to the literature. The polymorphous character of the clinical pictures requires a better collaboration between specialists leading to a clinical and holistic synthesis.

关键词： APs Biermer Graves’ Disease Hashimoto’s Addison’s Vitiligo senegal

Ballistic response of skin simulant against fragment simulating projectiles

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Defence Technology（防务技术） 2023年第12期30卷 70-82页

作者： Punit kumar Pandey Atul Harmukh m.K.Khan m.A.Iqbal s.G.Ganpule Department of mechanical and Industrial Engineering Indian Institute of Technology Roorkee247667India Department of Civil Engineering Indian Institute of Technology Roorkee247667India Department of Design Indian Institute of Technology Roorkee247667India

The response of biological phantoms against high velocity impact is actively sought for applications in defense,space,soft robotics and *** this end,we study the ballistic response of silicone based skin simulant against fragment *** a pneumatic gas gun setup,six chisel-nosed and three regular shaped(sphere,cylinder,and cube)fragments were impacted on the skin *** resulting skin simulant response was studied in terms of ballistic limit velocities,energy densities,failure pattern,and the mechanics of *** results indicate that the shape of the fragment affects the ballistic limit *** ballistic limit velocities,energy densities of the chisel-nosed fragment simulating projectiles were relatively insensitive to the size(mass),except for the smallest(0.16 g)and largest(2.79 g)chisel-nosed *** the same size(1 g),ballistic limit velocities and failure are dependent on the shape of the *** skin simulant failed by combined plugging and elastic hole *** in the spherical fragment was dominated by the elastic hole enlargement,whereas plugging failure was dominant in all other *** spherical,cylindrical,and chisel-nosed fragments created circular cavities,and the cubical fragment created a square *** the case of the spherical fragment,slipping of the fragment within the skin simulant was *** fragments created lateral cracks emanating from the corners of the square ***,for all the fragments,the maximum deformation corresponding to the perforation was lower than the non-perforation indicating rate dependent,stress driven *** maximum deformation was also dependent on the shape of the ***,these results provide unique insights into the mechanical response of a soft simulant against ballistic *** have utility in the calibration and validation of computational models,design of personal protective equipment,and antipersonnel syste

关键词： skin simulant Fragment Impact Ballistic limit velocity Energy density Failure

Failure investigation on high velocity impact deformation of boron carbide(B_(4)C) reinforced fiber metal laminates of titanium/glass fiber reinforced polymer

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Defence Technology（防务技术） 2022年第6期18卷 963-975页

作者： s.suresh kumar P.A.shankar K.Lalith kumar Department of mechanical Engineering Sri Sivasubramaniya Nadar College of EngineeringKalavakkamChennai603110India

High velocity ballistic impact deformation behaviour of Titanium/GFRP Fiber metal Laminates(FmL)has been *** single and multiple projectiles impact conditions were ***/GFRP FmL targets were fabricated with addition of 5%and 10%weight percentage of boron carbide(B_(4)C)*** properties of Ti/GFRP FmL targets were determined as per AsTm *** velocity ballistic experiments were conducted using Armour Piercing Projectile(APP)of diameter 7.62 mm and velocity ranging between 350 and 450 m/*** of penetration of the projectile into the target was *** deformation behaviour of Ti/GFRP targets with and without the presence of ceramic powder(B_(4)C)was investigated.“Ductile hole growth”failure mode was observed for pure GFRP target when subjected to single projectile impact whereas“plugging”failure mode was noted for Ti/GFRP *** presence of B_(4)C(5%by weight)particles has significantly improved the ballistic resistance of the Ti/GFRP FmL target by offering frictional resistance to the projectile *** addition(10%by weight)of B_(4)C has reduced the ballistic performance due to *** of the targets showed‘brittle cracking’or‘fragmentation’*** compared to the published results of Aluminium(Al 1100/GFRP and Al 6061/GFRP)FmLs,Ti/GFRP FmL showed lesser DoP which increases its potential application to aerospace industry.

关键词： Ti/GFRP FmL Ballistic impact Armour piercing projectile Boron carbide Depth of penetration Plugging

Fuzzy Based Ant Colony Optimization scheduling in Cloud Computing

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Computer systems science & Engineering 2022年第2期40卷 581-592页

作者： K.Rajakumari m.Vinoth kumar Garima Verma s.Balu Dilip kumar sharma sudhakar sengan Department of Computer science and Engineering School of EngineeringAvinashlingam Institute for Home Science and Higher Education for WomenCoimbatore641043Tamil NaduIndia Department of Information science and Engineering Dayananda Sagar Academy of Technology and ManagementBangalore560082India school of Computing DIT UniversityDehradun248009UttarakhandIndia Department of Computer science and Engineering Paavai Engineering CollegePachal637018Tamil NaduIndia Department of mathematics Jaypee University of Engineering and TechnologyGuna473226M.P.India Department of Computer science and Engineering PSN College of Engineering and TechnologyTirunelveli627152Tamil NaduIndia

Cloud computing is an Information Technology deployment model established on *** scheduling states the set of rules for task allocations to an exact virtual machine in the cloud computing ***,task scheduling challenges such as optimal task scheduling performance solutions,are addressed in cloud ***,the cloud computing performance due to task scheduling is improved by proposing a Dynamic Weighted Round-Robin *** recommended DWRR algorithm improves the task scheduling performance by considering resource competencies,task priorities,and ***,a heuristic algorithm called Hybrid Particle swarm Parallel Ant Colony Optimization is proposed to solve the task execution delay problem in DWRR based task *** the end,a fuzzy logic system is designed for HPsPACO that expands task scheduling in the cloud environment.A fuzzy method is proposed for the inertia weight update of the PsO and pheromone trails update of the ***,the proposed Fuzzy Hybrid Particle swarm Parallel Ant Colony Optimization on cloud computing achieves improved task scheduling by minimizing the execution and waiting time,system throughput,and maximizing resource utilization.

关键词： Cloud Computing scheduling ant colony optimization fuzzy logic

降雨诱发滑坡的NPR锚索控制机理及临滑预警

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东北大学学报（自然科学版） 2024年第4期45卷 573-583页

作者：陶志刚史广诚杨晓杰何满潮中国矿业大学(北京)隧道工程灾变防控与智能建养全国重点实验室北京100083 中国矿业大学(北京)力学与土木工程学院北京100083

为研究降雨滑坡的控制及临滑预警技术,以熊家山滑坡为原型,通过分析边坡变形的时空特征,设计了相似模型试验.以普通预应力锚索(简称PR锚索)和NPR锚索为加固材料,运用高速摄像机、孔压、土压和锚索力传感器,分析了降雨诱发的滑坡规律和... 详细信息

为研究降雨滑坡的控制及临滑预警技术,以熊家山滑坡为原型,通过分析边坡变形的时空特征,设计了相似模型试验.以普通预应力锚索(简称PR锚索)和NPR锚索为加固材料,运用高速摄像机、孔压、土压和锚索力传感器,分析了降雨诱发的滑坡规律和锚索控制机理,并结合现场试验探究了滑坡牛顿力变化规律.结果表明:孔隙水压力突降与边坡局部滑塌近似同步;NPR锚索力突降,边坡内部产生局部变形;PR锚索因无法承受大变形被拉断失效,而NPR锚索凭借恒阻大变形特性产生高应力吸能控制功能,促使边坡达到二次平衡状态;NPR锚索在滑坡前表现出明显的“先突增,后突降”的变形-临滑动力学规律;现场试验揭示了滑坡全过程牛顿力演变规律,提前7.5 h发出临滑预警.

关键词：滑坡降雨 NPR锚索控制机理监测预警

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超低损耗硫系光纤制备与中红外激光传输性能

光学学报 2024年第7期44卷 116-124页

作者：许彦涛郭海涛肖旭升李曼闫萌萌中国科学院西安光学精密机械研究所瞬态光学与光子技术国家重点实验室陕西西安710119 电磁空间安全全国重点实验室天津300308

硫系玻璃作为一种优秀的红外材料,具有透过范围广、物化性能稳定、易于成纤等特点,是制备红外传能光纤的理想材料之一。从硫系玻璃吸收损耗抑制和散射损耗抑制两方面入手,采用气(氯气)/气(玻璃蒸汽)、固(铝)/液(玻璃熔液)化学反应除杂... 详细信息

硫系玻璃作为一种优秀的红外材料,具有透过范围广、物化性能稳定、易于成纤等特点,是制备红外传能光纤的理想材料之一。从硫系玻璃吸收损耗抑制和散射损耗抑制两方面入手,采用气(氯气)/气(玻璃蒸汽)、固(铝)/液(玻璃熔液)化学反应除杂方式降低光纤吸收损耗,建立了三维激光显微成像系统,检测玻璃及光纤内部的微米和亚微米量级的缺陷,优化制备工艺降低光纤散射损耗,制备出损耗为0.087 dB/m(@4.778μm)的硫系玻璃光纤。分别利用光纤激光器(波长为2.0μm)和双波长输出的光学参量振荡器(OPO)激光器(波长为3.8μm和4.7μm)进行激光传能实验,在单模光纤和多模光纤中分别实现了6.10 W(@2.0μm)和6.12 W(@3.8μm和4.7μm)激光传输。

关键词：材料红外光纤硫系玻璃超低损耗激光传输激光损伤

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