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Cutting edge preparation of microdrills by shear thickening polishing for improved hole quality in electronic PCBs

Frontiers of Mechanical Engineering 2024年第2期19卷 99-107页

作者： Jiahuan WANG Mingfeng KE Jiepei LIAO Yu ZHOU Saurav GOEL Jaya verma Xu WANG Weigang GUO Julong YUAN Binghai LYU College of Mechanical Engineering Zhejiang University of TechnologyHangzhou 310000China Ultra-precision Machining Center Key Laboratory of Special Purpose Equipment and Advanced Manufacturing TechnologyZhejiang University of TechnologyHangzhou 310000China School of Engineering London South Bank UniversityLondon SE10AAUK Shenzhen Jinzhou Precision Technology Corporation Shenzhen 518116China Department of Mechanical Engineering University of Petroleum and Energy StudiesDehradun 248007India Special Equipment Institute Hangzhou Vocational&Technical CollegeHangzhou 310018China

Printed circuit boards(PCBs)are representative composite materials,and their high-quality drilling machining remains a persistent challenge in the industry.The finishing of the cutting edge of a microdrill is crucial to drill performance in machining fine-quality holes with a prolonged tool life.The miniature size involving submicron scale geometric dimensions,a complex flute shape,and low fracture toughness makes the cutting edge of microdrills susceptible to breakage and has been the primary limiting factor in edge preparation for microdrills.In this study,a newly developed cutting edge preparation method for microdrills was tested experimentally on electronic printed circuit boards.The proposed method,namely,shear thickening polishing,limited the cutting edge burrs and chipping on the cutting edge,and this in turn transformed the cutting edge’s radius from being sharp to smooth.Moreover,the edge–edge radius could be regulated by adjusting the processing time.PCB drilling experiments were conducted to investigate the influence of different cutting edge radii on wear,hole position accuracy,nail head value,and hole wall roughness.The proposed approach showed 20%enhancement in hole position accuracy,33%reduction in the nail head value,and 19%reduction in hole wall roughness compared with the original microdrill.However,a threshold is needed;without it,excessive shear thickening polishing will result in a blunt edge,which may accelerate the wear of the microdrill.Wear was identified as the primary factor that reduced hole quality.The study indicates that in printed circuit board machining,microdrills should effectively eliminate grinding defects and maintain the sharpness of the cutting edge as much as possible to obtain excellent drilling quality.Overall,shear thickening polishing is a promising method for cutting edge preparation of microdrills.Further research and optimization can lead to additional improvements in microdrill performance and contribute to the continued advancement of printed circuit board manufa

关键词： microdrill shear thickening polishing cutting edge preparation electronic printed circuit boards hole quality

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Geochemistry and mineralogy of beach sediments in the northern Gulf of Mexico,Tamaulipas state, Mexico: implication for provenance

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Journal of Palaeogeography 2024年第3期13卷 375-400页

作者： Mayank Shukla Sanjeet K.verma Mayla A.Ramos-vázquez John S.Armstrong-Altrin Karla R.Hernández-Martínez Sumit Mishra vivek P.Malviya Héctor Hernández-Mendoza Posgrado de la División de Geociencias Aplicadas Instituto Potosino de Investigación Científica y Tecnológica (IPICYT) División de Geociencias Aplicadas Instituto Potosino de Investigación Científica y Tecnológica (IPICYT) Universidad Nacional Autónoma de México Instituto de Ciencias del Mar y Limnología Unidad de Procesos Oceanicos y Costeros Ciudad Universitaria Department of Marine Sciences Bharathidasan University Instituto de Geociencias Universidad Nacional Autónoma de México Department of Applied Geology Dr.Harisingh Gour Central University Instituto de Investigación de Zonas Desérticas Universidad Autónoma de San Luis Potosí Universidad del Centro de México

Geochemical and mineralogical studies were performed in the La Pesca(LP) and Tesoro Altamira(TA) beach sediments, located in the Tamaulipas state, northern Gulf of Mexico. The main aim of this study is to infer the weathering history and provenance and to discriminate the tectonic environment of the beach sediments. The sediments are composed of quartz with small amounts of accessory minerals such as plagioclase, calcite, orthoclase, microcline, and zircon. Both beach sediments are classified as fine-grained and very well sorted, however LP has coarse skewed and leptokurtic sediments, whereas TA has fine-skewed and very leptokurtic sediments. The chemical index of weathering(CIW') indicates intense weathering in the source area. The quartz grain microtextures in the LP and TA are classified into mechanical, chemical, and mechanical/chemical origin. Mechanical features such as fractures, pits, percussion marks, abrasion fatigue, and v-shaped marks favor high-energy littoral, fluvial, subaqueous-marine, and aeolian environments. The chemical features indicate solution pits and crystalline overgrowth, which suggests a silica saturated marine environment. The mechanical/chemical features display adhering particles and elongated depressions suggest formation in a sub-aqueous nearshore marine environment. Major and trace elements-based provenance discrimination diagrams indicate a felsic source derived from the Mesa Central(MC), Sierra Madre Oriental(SMOr) and Oaxaquia terranes. The major and trace element concentrations imply a passive margin setting for the northern Gulf of Mexico, which is consistent with the general geology.

关键词： Beach sediments Geochemistry Mineralogy Provenance Tamaulipas Tectonic setting

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Autonomous UAv 3D trajectory optimization and transmission scheduling for sensor data collection on uneven terrains

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Defence Technology（防务技术） 2023年第12期30卷 154-160页

作者： Andrey v.Savkin Satish C.verma Wei Ni School of Electrical Engineering and Telecommunications University of New South WalesSydneyAustralia Data61 CSIROCanberraACT2601Australia

This paper considers a time-constrained data collection problem from a network of ground sensors located on uneven terrain by an Unmanned Aerial vehicle(UAv),a typical Unmanned Aerial System(UAS).The ground sensors harvest renewable energy and are equipped with batteries and data buffers.The ground sensor model takes into account sensor data buffer and battery limitations.An asymptotically globally optimal method of joint UAv 3D trajectory optimization and data transmission schedule is developed.The developed method maximizes the amount of data transmitted to the UAv without losses and too long delays and minimizes the propulsion energy of the UAv.The developed algorithm of optimal trajectory optimization and transmission scheduling is based on dynamic programming.Computer simulations demonstrate the effectiveness of the proposed algorithm.

关键词： Unmanned aerial system UAS Unmanned aerial vehicle UAv Wireless sensor networks UAS-Assisted data collection 3D trajectory optimization Data transmission scheduling

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A comprehensive review on energy storage in hybrid electric vehicle

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Journal of Traffic and Transportation Engineering(English Edition) 2021年第5期8卷 621-637页

作者： Shrey verma Shubham Mishra Ambar gaur Subhankar Chowdhury Subhashree Mohapatra gaur.v Dwivedi Puneet verma Energy Centre Maulana Azad National Institute of TechnologyBhopal 462007India School of Earth and Atmospheric Sciences Queensland University of TechnologyBrisbane 4001Australia

The sharp inclination in the emissions from conventional vehicles contribute to a significant increase in environmental issues,besides the energy crises and low conversion efficiency leads to the evolution of electric vehicles(Ev).Hybrid electric vehicles(HEv) have efficient fuel economy and reduce the overall running cost,but the ultimate goal is to shift completely to the pure electric vehicle.Despite this,the main obstruction of HEv is energy storage capability.An Ev requires high specific power(W/kg) and high specific energy(W$h/kg) to increase the distance travelled and reduce the time required for charging.The main focus of this paper is on the energy sources as these are the main components in Evs towards making them eco-friendly and cost-effective.various topologies of Ev technology such as HEvs,plug-in HEvs,and many more have been discussed.These topologies of Evs are based on the diverse combination of batteries,fuel cells,super-capacitor,flywheels,regenerative braking systems,which are used as energy sources and energy storage devices.

关键词： Electric vehicle Energy storage Battery electric vehicle Hybrid electric vehicles

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The role and significance of Magnesium in modern day research-A review

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Journal of Magnesium and Alloys 2022年第1期10卷 1-65页

作者： S v Satya Prasad S B Prasad Kartikey verma Raghvendra Kumar Mishra vikas Kumar Subhash Singh Department of Production and Industrial Engineering National Institute of Technology JamshedpurJharkhand831014India Department of Chemical Engineering Indian Institute of TechnologyKanpur208016India Enhanced Composites and Structures Center School of AerospaceTransport and ManufacturingCranfield UniversityBedfordshire MK43 OALUK Department of Automotive Technology Mechanical Department DivisionFederal TVET instituteAddis AbabaEthiopia

Magnesium is one of the largely available elements in the earth’s crust. It has a low structural density with high specific strength. This unique material property has forced an increase in the use of magnesium and its alloys in various applications pertaining to industrial sector,automobiles, aerospace and biomedical. Since magnesium is a highly reactive metal, it is prone to higher rate of corrosion as compared to its counterparts. Thus, it is essential to analyze the corrosion behavior of magnesium and its alloys in its applications. An appropriate process is to be followed in the design and development of magnesium alloys which overcome the limitations of magnesium and enhance the desired material properties in accordance to their applications. This review paper summarizes the importance of magnesium and its material properties. The influence of various alloying elements on the mechanical properties of magnesium is reviewed. The broad classification of Mg alloys and their behavioral trends are detailed. The corrosion behavior of magnesium and the influence of corrosion products on the material characteristics of magnesium, in aqueous medium, are discussed. The manufacturing techniques of magnesium alloys along with the secondary techniques are also covered. The various applications and the limitations of magnesium in these applications are covered. A complete section is dedicated towards detailing the recent trends of magnesium(Mg) alloys, i.e., the biodegradable nature and applications of Mg alloys. The influence of biocorrosion on Mg alloys and techniques to overcome it have been deliberated. This paper provides a thorough review on recent developments of magnesium with respect to engineering applications.

关键词： Magnesium alloys Biodegradable alloys Magnesium corrosion Biocorrosion

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Fuzzy Based Reliable Load Balanced Routing Approach for Ad hoc Sensor Networks

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Computer Systems Science & Engineering 2022年第6期41卷 861-874页

作者： J.v.Anchitaalagammai Rajesh verma M.Kavitha A.R.Revathi S.R.Preethi Kiranmai Bellam Department of Computer Science and Engineering Velammal College of Engineering and TechnologyMadurai625009TamilNaduIndia Department of Electrical Engineering King Khalid UniversityAbha62529Saudi Arabia Department of Electronics and Communication Engineering K.Ramakrishnan College of TechnologyTiruchirappalli621112Tamil NaduIndia Department of Information Technology SRM Valliammai Engineering CollegeChennai603203Tamil NaduIndia Department of Electronics and Communication Engineering SRM Valliammai Engineering CollegeChennai603203Tamil NaduIndia Department of Computer Science Prairie View A&M UniversityPrairie ViewTXUnited State

Energy management and packet delivery rate are the important factors in ad hoc networks.It is the major network where nodes share the information without administration.Due to the mobility of nodes,maximum energy is spent on transmission of packets.Mostly energy is wasted on packet dropping and false route discovery.In this research work,Fuzzy Based Reliable Load Balanced Routing Approach(RLRA)is proposed to provide high energy efficiency and more network lifetime using optimal multicast route discovery mechanism.It contains three phases.In first phase,optimal multicast route discovery is initiated to resolve the link failures.In second phase,the link quality is estimated and set to threshold value to meet the requirements of high energy efficiency.In third phase,energy model is shown to obtain total energy of network after transmission of packets.A multicast routing is established Based on path reliability and fault tolerant calculation is done and integrated with multicast routing.The routes can withstand the malicious issues.Fuzzy decision model is integrated with propose protocol to decide the performance of network lifetime.The network simulation tool is used for evaluating the RLRA with existing schemes and performance of RLRA is good compared to others.

关键词： Fuzzy model link quality multicast route energy model cluster group node lifetime

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Some Formulas Involving Hypergeometric Functions in Four variables

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Computer Modeling in Engineering & Sciences 2022年第2期130卷 887-902页

作者： Hassen Aydi Ashish verma Jihad Younis Jung Rye Lee Universit´e de Sousse Institut Sup´erieur D’Informatique etDes Techniques de CommunicationH.Sousse4000Tunisia Department of Mathematics and Applied Mathematics Sefako Makgatho Health Sciences UniversityGa-RankuwaSouth Africa ChinaMedical University Hospital ChinaMedical UniversityTaichung40402Taiwan Department of Mathematics V.B.S.Purvanchal UniversityJaunpur222003India Department of Mathematics Aden UniversityKhormaksarP.o.Box 6014Yemen Department of Data Science Daejin UniversityKyunggi11159Korea

Several(generalized)hypergeometric functions and a variety of their extensions have been presented and investigated in the literature by many authors.In the present paper,we investigate four new hypergeometric functions in four variables and then establish several recursion formulas for these new functions.Also,some interesting particular cases and consequences of our results are discussed.

关键词： Recursion formula quadruple hypergeometric functions pascal identity

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Autochthonous halotolerant plant growth-promoting rhizobacteria promote bacoside A yield of Bacopa monnieri(L.)Nash and phytoextraction of salt-affected soil

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Pedosphere 2020年第5期30卷 671-683页

作者： Umesh PANKAJ Durgesh Narain SINGH Pooja MISHRA Pooja gaur C.S.vivek BABU Karuna SHANKER Rajesh Kumar verma Department of Soil Science CSIR-Central Institute of Medicinal and Aromatic PlantsLucknow 226015(India) Division of Biotechnology CSIR-Central Institute of Medicinal and Aromatic PlantsLucknow 226015(India) Division of Microbial Technology CSIR-Central Institute o f Medicinal and Aromatic PlantsLucknow 226015(India) Analytical Chemistry Department CSIR-Central Institute o f Medicinal and Aromatic PlantsLucknow 226015(India) Research Centre CSIR-Central Institute of Medicinal and Aromatic PlantsBangalore 560065(India)

Phytoremediation is a promising approach for reclamation of salt-affected soil.Phytoextraction is the most commonly used process,which exploits plants to absorb,immobilize,and accumulate salt in their shoots.In this study,halotolerant plant growth-promoting rhizobacteria(PGPR)were isolated from the rhizosphere of wild grasses growing naturally in salt-affected areas of Lucknow,Uttar Pradesh(India)and were tested for their efficacies of salt-tolerance and plant growth-promoting(PGP)abilities.Based on 16S rRNA sequences,the most efficient halotolerant isolates possessing PGP traits were identified as Pseudomonas plecoglossicida(KM 233646),Acinetobacter calcoaceticus(KM 233647),Bacillus flexus(KM 233648),and Bacillus safensis(KM 233652).Application of these isolates as bio-inoculants significantly(Pvident by the substantial increase in shoot Na^+:K^+ratio of bio-inoculant-treated plants.When compared to un-inoculated control plants,the soil physico-chemical properties of bio-inoculant-treated plants were improved.The shoot and root biomass(fresh and dry weights),soil enzymes,and soil nutrient parameters showed significant positive correlations with the shoot Na+:K+ratio.Consequently,the halotolerant PGPR screened in this study could be useful for the reclamation of saline soils concomitant with improved plant growth and bacoside A yield.

关键词： bio-inoculant phytoremediation plant productivity soil physico-chemical property soil salinity

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Effect of Semecarpus anacardium fruits on reproductive function of male albino rats

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Asian Journal of Andrology 2003年第2期5卷 121-124页

作者： Arti Sharma Pramod Kumar verma v.P.Dixit Department of Zoology Raj Rishi Colloge A/war (Raj) 301001 IndiaReproductive Physiology Section Department of Zoology University of Rajasthan Jaipur-302 004 IndiaReproductive Physiology Section Department of Zoology University of Rajasthan Jaipur-302 004 India

Aim: To evaluate the effect of an ethanolic extract of Semecarpus anacardium fruits on spermatogenesis in albino rats. Methods: Male albino rats were fed with a 50 % ethanolic extract of Semecarpus anacardium fruit at 100 mg·kg-1.day-1, 200 mg·kg-1·day-1 and 300 mg·kg-1·day-1 for 60 days. Fertility test was performed after 60 days of treatment. Sperm motility and density were observed in the cauda epididymis. Biochemical and histological analyses of the blood and reproductive organs were done. Recovery of fertility was followed to evaluate the reversibility of drug action. Results: S. anacardium fruit extract administration resulted in spermatogenic arrest in albino rats. The sperm motility and density was reduced significantly. The RBC and WBC counts, haemoglobin, haematocrit, blood sugar and urea were found to be within the normal range in the whole blood. The protein, cholesterol and glycogen in the testes and the fructose in the seminal vesicle were significantly decreased after the treatment. The fruit extract feeding caused marked reduction in the number of primary spermatocytes, secondary spermatocytes and spermatids. The number of mature Leydig cells was also decreased and degenerating cells increased proportionately. Conclusion: 5. anacardium fruit extract causes spermatogenic arrest in albino rats.

关键词： Semecarpus anacardium spermatogenesis androgen spermatocytes Leydig cells

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Bacterial and fungal co-infection is a major barrier in COvID-19 patients:A specific management and therapeutic strategy is required

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World Journal of virology 2022年第2期11卷 107-110页

作者： Tarun Sahu Henu Kumar verma Lakkakula v K S Bhaskar Department of Physiology All India Institute of Medical ScienceRaipur 492001ChhattisgarhIndia Department of Immunopathology Institute of Lung Health and ImmunityComprehensive Pneumology CenterHelmholtz ZentrumMunich 85764Germany Department of Zoology Guru Ghasidas VishwavidyalayaBilaspur 495001ChhattisgarhIndia

Microbial co-infections are another primary concern in patients with coronavirus disease 2019(COvID-19),yet it is an untouched area among researchers.Preliminary data and systematic reviews only show the type of pathogens responsible for that,but its pathophysiology is still unknown.Studies show that these microbial co-infections are hospital-acquired/nosocomial infections,and patients admitted to intensive care units with invasive mechanical ventilation are highly susceptible to it.Patients with COvID-19 had elevated inflammatory cytokines and a weakened cell-mediated immune response,with lower CD4+T and CD8+T cell counts,indicating vulnerability to various co-infections.Despite this,there are only a few studies that recommend the management of coinfections.

关键词： COvID-19 Co-infection Bacterial co-infection Fungal co-infection

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