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Measurement of bit-rock interface temperature and wear rate of the tungsten carbide drill bit during rotary drilling

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Friction 2020年第6期8卷 1073-1082页

作者： vijay kumar SHANKAR Bijay Mihir KUNAR Chivukula Suryanarayana MURTHY M R RAMESH Department of Mining Engineering National Institute of Technology KarnatakaSurathkal 575025India Department of Mechanical Engineering National Institute of Technology KarnatakaSurathkal 575025India

Rock drilling is an essential operation in mining *** at the bit-rock interface plays a major role in the wear rate of the drill *** paper primarily focuses on the wear rate of tungsten carbide(WC)drill bit and the interrelationship between temperature and wear rate during rotary drilling operations conducted using a computer numerical control(CNC)*** interrelationship between the temperature and wear rate was studied with regard to three types of rock samples,i.e.,fine-grained sandstone(FG)of uniaxial compressive strength(UCS)that is 17.83 MPa,medium-grained sandstone(MG)of UCS that is 13.70 MPa,and fine-grained sandstone pink(FGP)of UCS that is 51.67 *** rate of the drill bit has been measured using controlled parameters,i.e.,drill bit diameter(6,8,10,12,and 16 mm),spindle speed(250,300,350,400,and 450 rpm),and penetration rate(2,4,6,8,and 10 mm/min),***,a fully instrumented laboratory drilling set-up was *** weight of each bit was measured after the bit reached 30 mm depth in each type of the rock ***,effects of the bit-rock interface temperature and operational parameters on wear rate of the drill bits were *** results show that the wear rate of drill bits increased with an increase in temperature for all the bit-rock combinations *** is due to the silica content of the rock sample,which leads to an increase in the frictional heat between the bit-rock ***,in case of medium-grained sandstone,the weight percentage(wt%)of SiO2 is around 7.23 wt%,which presents a very low wear rate coefficient of 6.33×10^–2 mg/(N?m).Moreover,the temperature rise during drilling is also minimum,i.e.,around 74℃,in comparison to that of fine-grained sandstone and fine-grained sandstone *** addition,this paper develops the relationship between temperature and wear rate characteristics by employing simple linear regression analysis.

关键词： temperature wear rate drilling simple linear regression

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Effect of E-Learning on Public Health and Environment During COVID-19 Lockdown

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Big Data Mining and Analytics 2021年第2期4卷 104-115页

作者： Avani Agarwal Sahil Sharma vijay kumar Manjit Kaur Department of Computer Science Thapar Institute of Engineering and TechnologyPatiala 147001India Department of Computer Science and Engineering National Institute of TechnologyHamirpurHimachal Pradesh 177005India Department of Computer Science Engineering School of Engineering and Applied SciencesBennett UniversityGreater Noida 201310India

E-learning is the most promising venture in the entire world. During the COVID-19 lockdown, e-learning is successfully providing potential information to the students and researchers. In developing nations like India, with limited resources, e-learning tools and platforms provide a chance to make education available to middle and low income households. This paper gives insights about three different online services, namely Google Classroom,Zoom, and Microsoft Teams being used by three different educational institutions. We aim to analyze the efficiency and acceptability of e-learning tools among Indian students during the COVID-19 lockdown. The paper also aims to evaluate the impact of e-learning on the environment and public health during COVID-19 lockdown. It is found that e-learning has potential to reduce carbon emissions, which has beneficial impact on the environment. However, the mental health is impacted as e-learning may lead to self-isolation and reduction in academic achievements that may lead to anxiety and mental depression. Due to usage of electronic devices for learning, the eyes and neck muscles may be put in strain, having deleterious effects on physical health.

关键词： e-learning environment health COVID-19

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Biopolymers and Biomimetic Materials in Medical and Electronic-Related Applications for Environment-Health-Development Nexus:Systematic Review

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Journal of Bionic Engineering 2022年第6期19卷 1562-1577页

作者： Faris Mohammed AL-Oqla Mohammed Hassouna Alaaeddin Muhammad Enamul Hoque vijay kumar Thakur Department of Mechanical Engineering Faculty of EngineeringThe Hashemite UniversityP.O Box 330127Zarqa13133Jordan University College Fairview 2AJalan TP2Sime UEP Industrial Park Subang Jaya47600Subang JayaSelangorMalaysia Department of Biomedical Engineering Military Institute of Science and Technology(MIST)Mirpur CantonmentDhaka1216Bangladesh Biorefining and Advanced Materials Research Center Scotland’s Rural College(SRUC)Kings BuildingsEdinburghEH93JGUK School of Engineering University of Petroleum&Energy Studies(UPES)Dehradun248007UttarakhandIndia

Biocomposites as bio-inspired materials are produced from renewable resources that are organic and ecofriendly alternative *** improve the lifestyle of human beings as well as enhancing the environmental indices,functional bio-materials are now implemented in various promising *** work has systematically discussed and highlighted the implementations and trends of functional bionic materials in high tech industries,which are necessary for developing modern *** medical,electronic,food and pharmaceutical applications have been ***-inspired materials are used to develop more sustainable possibilities to increase environmental conservation while maintaining customer *** were found employed in several sectors for various functional bio-products including organic thin-film transistors,organic phototransistor,emitting diodes,photodiodes,photovoltaic solar cells,hybrid dental resins,sustainable pharmaceuticals,and food *** are used to create sustainable bio-products for energy storage and harvesting,bone regeneration,nerve damage repair,drug applications and various other industrial subcategories.

关键词： Biopolymers Bioinspired Biomimetic materials Tissue engineering Nerve repair Organic transistors

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Bio-effects of 5th generation electromagnetic waves on organs of human beings

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Global Health Journal 2023年第4期7卷 206-211页

作者： Amit Verma vijay kumar Shipra Gupta Graphic Era Hill University DehardunUttrakhand 248001India

Objectives:The uses of devices of electromagnetic waves(EMWs)are increasing day by ***,the generation of the waves is *** frequency spectrum of the generation of waves is also *** this manuscript,an analysis of the high frequency EMWs has been made by the electric fields generated due to the exposure of 5th generation(5 G)of mobile ***:Due to the emission of waves from the towers,the electric field is generated around the transmission tower of mobile *** electric fields are computed by the power of the transmission *** electric fields across the biological tissues/cells are also computed when the EMWs penetrate inside the *** electric fields are made across the organs of different depths inside the ***:The induced electric fields inside the organs of the human beings are responsible for the absorption of energy from high frequency *** absorbed amount of energy from high frequency waves may become the cause of harmful effects on the life of organs of human ***:In this manuscript,after analysis of the computed electric fields inside the organs of human beings,it is concluded that the EMWs of 5 G spectrum of mobile phone towers may more harmful for the life of organs as 4th generation(4 G)spectrum of mobile phone *** energy absorption by the 4 G spectrum is lower than 5 G spectrum due to the range of frequency of *** effects on the pancreas,retina,skin,intestine,spleen,stomach and uterus are more than low water content organs like nails,bone,teeth etc.

关键词： Fifth generation Electromagneticwaves Mobile phonetowers Bio-effects Human beings tissues Organs

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Reciprocating sliding tribology of brake oil treated carbon fiber reinforced ceramic matrix composites

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Transactions of Nonferrous Metals Society of China 2019年第9期29卷 1903-1913页

作者： Parshant kumar vijay kumar SRIVASTAVA Department of Mechanical Engineering Indian Institute of Technology (Banaras Hindu University)

The effect of brake oil on sliding behavior of carbon/carbon(C/C) and carbon/carbon-silicon carbide(C/C-SiC) composites was investigated with the variation of laminate orientation and surface conformity. The partial and low conformity contacts with the normal and parallel orientations of laminates were considered. The normal load was varied from 50 to 90 N in a step of 10 N. The friction and wear behavior was investigated under reciprocating sliding conditions. The results showed that friction coefficient and wear loss of composites with normal orientation of laminates were larger as compared to those of composites with parallel orientation of laminates. C/C composites with normal orientation of laminates yielded the highest value of friction coefficient. Wear loss decreased by a maximum of 78%, and friction coefficient decreased by a maximum of 49% in low conformity contacts as compared to partial conformity contacts. The presence of brake oil reduced the adhesion tendency of compacted wear debris because the formation of friction film was difficult, and thus, friction behavior was affected. The wear debris retention between the contact surfaces due to confined area motion in reciprocating sliding depicted the tribological behavior.

关键词： reciprocating sliding tribology C/C composites C/C-SiC composites friction coefficient wear resistance laminate orientation

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One Pot Reduction of Imines Generated in-situ from Aldehydes and Amines by the NaBH4-InCl3 System

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Chinese Journal of Chemistry 2006年第6期24卷 807-810页

作者： RAVI, Varala RAMU, Enugala vijay kumar, Ponnamaneni SRINIVAS RAO, Adapa Indian Institute of Chemical Technology Hyderabad-500 007 India

A combination of sodium borohydride and a catalytic amount of indium（Ⅲ） chloride in acetonitrile reduces imines formed in-situ from aldehydes and amines to the corresponding functionalised secondary and tertiary amines in moderate to good yields. Noteworthy is that highly chemoselective reactions were achieved in the presence of other functional groups such as halogens, carbon-carbon double bonds and hydroxyl groups.

关键词： NaBH4-InCl3 aldehyde amine One Pot Reduction

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Extent of mismatch between the period of circadian clocks and light/dark cycles determines time-to-emergence in fruit flies

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Insect Science 2015年第4期22卷 569-577页

作者： Pankaj Yadav Deepak Choudhury Madhumala K. Sadanandappa vijay kumar Sharma Chronobiology Laboratory Evolutionary and Organismal Biology Unit Jawaharlal Nehru Centre for Advanced Scientific Research Bangalore 560064 Kamataka India

Circadian clocks time developmental stages of fruit flies Drosophila melanogaster, while light/dark （LD） cycles delimit emergence of adults, conceding only during the ＂allowed gate.＂ Previous studies have revealed that time-to-emergence can be altered by mutations in the core clock gene period （per）, or by altering the length of LD cycles. Since this evidence came from studies on genetically manipulated flies, or on flies maintained under LD cycles with limited range of periods, inferences that can be drawn are limited. Moreover, the extent of shortening or lengthening of time-to-emergence re- mains yet unknown. In order to pursue this further, we assayed time-to-emergence of D. rnelanogaster under 12 different LD cycles as well as in constant light （LL） and constant dark conditions （DD）. Time-to-emergence in flies occurred earlier under LL than in LD cycles and DD. Among the LD cycles, time-to-emergence occurred earlier under T4-T8, followed by T36-T48, and then T12-T32, suggesting that egg-to-emergence duration in flies becomes shorter when the length of LD cycles deviates from 24 h, bearing a strong positive and a marginally negative correlation with day length, for values shorter and longer than 24 h, respectively. These results suggest that the extent of mismatch between the period of circadian clocks and environmental cycles determines the time-to-emergence in Drosophila.

关键词： circadian Drosophila light/dark regimes period time-to-emergence

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Conservation Strategy for African Medicinal Species: In Vitro Biotechnological Approach

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Phyton-International Journal of Experimental Botany 2020年第4期89卷 779-794页

作者： Priyanka Jha Swati Chahal Devendra kumar Pandey Joginder Singh Ram Prasad vijay kumar Amity Institute of Biotechnology Amity UniversityKolkataWest Bengal700156India Plant Biotechnology Laboratory Division of Research and DevelopmentLovely Professional UniversityPhagwara144411PunjabIndia Department of Biotechnology School of Bioengineering and BiosciencesLovely Professional UniversityPhagwara144411PunjabIndia Department of Microbiology School of Bioengineering and BiosciencesLovely Professional UniversityPhagwara144411PunjabIndia Department of Botany School of Life SciencesMahatma Gandhi Central UniversityMotihariBihar845401India

The use of medicinal plants for different therapeutic values is well documented in African *** diverse biodiversity hotspots provide a wide range of endemic species,which ensures a potential medicinal *** feasible conservation approach and sustainable harvesting for the medicinal species remains a huge ***,conservation approach through different biotechnological tools such as micropropagation,somatic embryogenesis,synthetic seed production,hairy root culture,molecular markers based study and cryopreservation of endemic African medicinal species is much *** this review,an attempt has been made to provide different in vitro biotechnological approaches for the conservation of African medicinal *** present review will be helpful in further technology development and deciding the priorities at decision-making levels for in vitro conservation and sustainable use of African medicinal species.

关键词： Biotechnological approach conservation medicinal plant African traditional medicine(ATM) start codon targeted polymorphism(SCoT) somatic embryogenesis

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Enhanced Field-Based Detection of Potato Blight in Complex Backgrounds Using Deep Learning

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Plant Phenomics 2021年第1期3卷 209-221页

作者： Joe Johnson Geetanjali Sharma Srikant Srinivasan Shyam kumar Masakapalli Sanjeev Sharma Jagdev Sharma vijay kumar Dua School of Computing&Electrical Engineering Indian Institute of Technology MandiKamandH.P.India BioX Center School of Basic SciencesIndian Institute of Technology MandiKamandH.P.India ICAR-Central Potato Research Institute H.P.ShimlaIndia

Rapid and automated identification of blight disease in potato will help farmers to apply timely remedies to protect their *** detection of blight disease can be cumbersome and may require trained *** overcome these issues,we present an automated system using the Mask Region-based convolutional neural network(Mask R-CNN)architecture,with residual network as the backbone network for detecting blight disease patches on potato leaves in field *** approach uses transfer learning,which can generate good results even with small *** model was trained on a dataset of 1423 images of potato leaves obtained from fields in different geographical locations and at different times of the *** images were manually annotated to create over 6200 labeled patches covering diseased and healthy portions of the *** Mask R-CNN model was able to correctly differentiate between the diseased patch on the potato leaf and the similar-looking background soil patches,which can confound the outcome of binary *** improve the detection performance,the original RGB dataset was then converted to HSL,HSV,LAB,XYZ,and YCrCb color spaces.A separate model was created for each color space and tested on 417 field-based test *** yielded 81.4%mean average precision on the LAB model and 56.9%mean average recall on the HSL model,slightly outperforming the original RGB color space *** analysis of the detection performance indicates an overall precision of 98%on leaf images in a field environment containing complex backgrounds.

关键词： Deep network backbone

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A Novel Binary Emperor Penguin Optimizer for Feature Selection Tasks

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Computers, Materials & Continua 2022年第3期70卷 6239-6255页

作者： Minakshi Kalra vijay kumar Manjit Kaur Sahar Ahmed Idris Saban Oturk Hammam Alshazly Computer Science Department Government College BahadurgarhBahadurgarh124507India CSE Department National Institute of Technology Hamirpur177005India School of Engineering and Applied Sciences Bennett UniversityGreater Noida201310India College of Industrial Engineering King Khalid UniversityAbhaSaudi Arabia Department of Electrical and Electronics Engineering Amasya UniversityAmasyaTurkey Faculty of Computers and Information South Valley UniversityQena83523Egypt

Nowadays,due to the increase in information resources,the number of parameters and complexity of feature vectors *** offermore practical solutions instead of exact solutions for the solution of this *** Emperor PenguinOptimizer(EPO)is one of the highest performing meta-heuristic algorithms of recent times that imposed the gathering behavior of emperor *** shows the superiority of its performance over a wide range of optimization problems thanks to its equal chance to each penguin and its fast convergence *** traditional EPO overcomes the optimization problems in continuous search space,many problems today shift to the binary search ***,in this study,using the power of traditional EPO,binary EPO(BEPO)is presented for the effective solution of binary-nature *** algorithm uses binary search space instead of searching solutions like conventional EPO algorithm in continuous search *** this purpose,the sigmoidal functions are preferred in determining the emperor *** addition,the boundaries of the search space remain constant by choosing binary ***’s performance is evaluated over twenty-nine benchmarking *** evaluations are made to reveal the superiority of the BEPO *** addition,the performance of the BEPO algorithm was evaluated for the binary feature selection *** experimental results reveal that the BEPO algorithm outperforms the existing binary meta-heuristic algorithms in both tasks.

关键词： Metaheuristics optimization algorithms emperor penguin optimizer intensification diversification feature selection

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