检索结果-南通市图书馆

Petroleum 2019年第1期5卷 1-12页

作者： Dipal Patel Vivek Thakar sivakumar pandian Manan Shah Anirbid Sircar School of Petroleum Technology Pandit Deendayal Petroleum UniversityGandhinagar382007India

The extraction of petroleum fluids from sub-surface accumulations mandates the drilling of a well into the formation containing the *** drilling techniques have evolved over time to overcome several challenges while some of the issues still prevail with the currently used drilling practices like loss circulation,large tripping time to change bottom hole assembly,stuck pipe problems and low well bore stability,to name a *** decrease the drilling efficiency and increase the Non-Productive Time(NPT)of this highly capitalintensive industry encouraging the Petroleum Industry to look for new *** while Drilling(CwD)is a technique of drilling which has been proven to alleviate many of the problems faced while *** this method,drilling and casing of a well bore is carried out simultaneously,which improves the drilling efficiency by reducing the *** has proven to be beneficial in controlling loss circulation and improving wellbore stability by‘Plastering’effect,high quality cement job and increased rig floor *** uses smaller rig and less fuel thereby reducing carbon footprint in the *** paper studies comprehensive well control and casing string design *** encourages its application that has been discussed in the paper.A case study on the application of CwD in Malay basin for top hole drilling is ***,the paper briefly outlines the technical challenges that need attention to get better results from CwD.

关键词： Casing while drilling Non productive time Plastering effect Well control

Optimal Control of Service Rates of Discrete-Time(s,Q)Queueing-Inventory Systems with Finite Buffer

在线全文

学校读者我要写书评

暂无评论

Journal of Systems Science and Systems Engineering 2024年第3期33卷 261-280页

作者： L.Iniya B.sivakumar G.Arivarignan School of Mathematics Madurai Kamaraj UniversityMaduraiTamilnaduIndia Department of Statistics Manonmaniam Sundaranar UniversityTirunelveliTamilnaduIndia

This article,we develop an optimal policy to control the service rate of a discrete time queueing-inventory system with finite *** customers arrive according to a Bernoulli process and the service time for the customers are *** the buffer size attains its maximum,any arriving new customers are considered to be *** customers are served one by one according to FCFS rule and each customers request random number of *** inventory is replenished according to a(s,Q)inventory policy with geometric lead *** main objectives of this article are to determine the service rates to be employed at each slot so that the long run expected cost rate is minimized for fixed inventory level and fixed buffer size and to minimize the expected waiting time for a fixed inventory level and fixed buffer *** problems are modelled as Markov decision *** establish the existence of a stationary policy and employ linear programming method to find the optimal service *** provide some numerical examples to illustrate the behaviour of the model.

关键词： Queueing-inventory system discrete time batch demand-Markov decision process

Smart Healthcare Activity Recognition Using Statistical Regression and Intelligent Learning

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Computers, Materials & Continua 2024年第1期78卷 1189-1205页

作者： K.Akilandeswari Nithya Rekha sivakumar Hend Khalid Alkahtani Shakila Basheer Sara Abdelwahab Ghorashi Department of Computer Sciences Government Arts College(Autonomous)Salem636007India Department of Computer Sciences College of Computer and Information SciencesPrincess Nourah Bint Abdulrahman UniversityRiyadh11671Saudi Arabia Department of Information Systems College of Computer and Information SciencesPrincess Nourah Bint Abdulrahman UniversityRiyadh11671Saudi Arabia

In this present time,Human Activity Recognition(HAR)has been of considerable aid in the case of health monitoring and *** exploitation of machine learning with an intelligent agent in the area of health informatics gathered using HAR augments the decision-making quality and *** many research works conducted on Smart Healthcare Monitoring,there remain a certain number of pitfalls such as time,overhead,and falsification involved during ***,this paper proposes a Statistical Partial Regression and Support Vector Intelligent Agent Learning(SPR-SVIAL)for Smart Healthcare *** first,the Statistical Partial Regression Feature Extraction model is used for data preprocessing along with the dimensionality-reduced features extraction ***,the input dataset the continuous beat-to-beat heart data,triaxial accelerometer data,and psychological characteristics were acquired from IoT wearable *** attain highly accurate Smart Healthcare Monitoring with less time,Partial Least Square helps extract the dimensionality-reduced *** that,with these resulting features,SVIAL is proposed for Smart Healthcare Monitoring with the help of Machine Learning and Intelligent Agents to minimize both analysis falsification and *** evaluation is carried out for factors such as time,overhead,and false positive rate accuracy concerning several *** quantitatively analyzed results indicate the better performance of our proposed SPR-SVIAL method when compared with two state-of-the-art methods.

关键词： Internet of Things smart health care monitoring human activity recognition intelligent agent learning statistical partial regression support vector

Insights into the anorexic mechanism of Khat:an integrated in vivo,ex vivo,and in silico investigations

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Traditional Medicine Research 2024年第10期9卷 36-51页

作者： Ahmed Ali Jerah Manal Mohamed Elhassan Taha Abdullah Farasani sivakumar Sivagurunathan Moni Emad Sayed Shaheen Andleeb Khan Ibrahim Abdo Khardali Magbool Oraiby Heyam Mohamed Ali Sidahmed Siddig Ibrahim Abdelwahab Department of Medical Laboratory Technology College of Applied Medical SciencesJazan UniversityJazan 45142Saudi Arabia Health Research Centre Jazan UniversityJazan 45142Saudi Arabia Department of Pharmaceutics College of PharmacyJazan UniversityJazan 45142Saudi Arabia Department of Biosciences Faculty of ScienceIntegral UniversityLucknow 226026India Poison Control and Medical Forensic Chemistry Center General Directorate of Health AffairsJazan 45142Saudi Arabia Department of Pharmaceutical Chemistry Faculty of PharmacyAl-Neelain UniversityKhartoum 16458Sudan

Background:Chewing Khat(Catha edulis)releases cathine and cathinone,which may reduce appetite via an unknown *** study investigated the peripheral and central effects of fresh leaves and buds of Catha edulis water extract(CEWE)on appetite biomarkers,gene expression,and body weight,using in vivo,ex vivo,and in silico ***:Rats of both sexes were orally administered CEWE at different doses and durations in three different *** chromatography-mass spectroscopy(LC-MS)-MS was used to detect cathinone and cathine in the murine *** effect of Khat on serotonin receptors was studied in isolated rat fundus *** of the two Khat ligands was performed on G(The 5-hydroxytryptamine-type 2C receptor(5-HT2C)in an agonist-bound active conformation)and H(5-HT2C in an antagonist-bound inactive conformation)proteins to determine which ligands are most likely to act as agonists or ***:Significant differences(P0.05).The expression of the ghrelin and leptin genes was also unaffected,but the expression of the 5-hydroxytryptamine(5-HT)gene decreased(P<0.05)with CEWE *** antagonizes 5-HT receptors in isolated rat fundus *** findings indicated that the khat ligands bound to 5-HT2C *** and cathinone levels in rat plasma were ***:Khat extract may suppress appetite by antagonizing the 5-HT *** research is required to understand its mechanism and potential applications.

关键词： Catha edulis appetite leptin ghrelin 5-hydroxytryptamine molecular docking

Sustainable Furfural Biomass Feedstocks Electrooxidation toward Value-Added Furoic Acid with Energy-Saving H_(2) Fuel Production Using Pt-Decorated Co_(3)O_(4) Nanospheres

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Energy & Environmental Materials 2024年第2期7卷 350-358页

作者： Talshyn Begildayeνa Jayaraman Theerthagiri Seung Jun Lee Ahreum Min Gyeong-Ah Kim Siνakumar Manickam Myong Yong Choi Department of Chemistry(BK21 FOUR) Core-Facility Center for Photochemistry&NanomaterialsResearch Institute of Natural SciencesGyeongsang National UniversityJinju 52828South Korea Petroleum and Chemical Engineering Faculty of EngineeringUniversiti Teknologi BruneiJalan Tungku Link GadongBandar Seri Begawan BE1410Brunei Darussalam

Here,furfural oxidation was performed to replace the kinetically sluggish O_(2)evolution reaction(OER).Pt-Co_(3)O_(4)nanospheres were developed via pulsed laser ablation in liquid(PLAL)in a single step for the paired electrocatalysis of an H_(2)evolution reaction(HER)and furfural oxidation reaction(FOR).The FOR afforded a high furfural conversion(44.2%)with a major product of 2-furoic acid after a 2-h electrolysis at 1.55 V versus reversible hydrogen electrode in a 1.0-M KOH/50-mM furfural *** Pt-Co_(3)O_(4)electrode exhibited a small overpotential of 290 mV at 10 mA cm^(-2).As an anode and cathode in an electrolyzer system,the Pt-Co_(3)O_(4)electrocatalyst required only a small applied cell voltage of~1.83 V to deliver 10 mA cm^(-2),compared with that of the pure water electrolyzer(OER||HER,~1.99 V).This study simultaneously realized the integrated production of energy-saving H_(2)fuel at the cathode and 2-furoic acid at the anode.

关键词： biomass conversion electrochemical furfural oxidation overall water splitting Pt-Co_(3)O_(4)electrocatalyst pulsed laser ablation in liquid

Impact of phytoconstituents on oral health practices:a post COVID-19 observation

在线全文

学校读者我要写书评

暂无评论

Food Science and Human Wellness 2024年第5期13卷 2386-2400页

作者： Harsh Kumar Reena Singh Daljeet Singh Dhanjal Chirag Chopra Natália Cruz-Martins Gheyath K.Nasrallah Amin F.Majdalawieh sivakumar Manickam Shahida Anusha Siddiqui Dinesh Kumar Indu Sharma Varun Sharma School of Bioengineering&Food Technology Shoolini University of Biotechnology and Management SciencesSolan 173229India School of Bioengineering and Biosciences Lovely Professional UniversityPunjab 144402India Faculty of Medicine University of PortoPorto 4200-319Portugal Institute for Research and Innovation in Health(i3S) University of PortoPorto 4200-135Portugal Institute of Research and Advanced Training in Health Sciences and Technologies(CESPU) RuaCentral de GandraGandra 4585-116Portugal TOXRUN-Toxicology Research Unit University Institute of Health SciencesCESPUCRLGandra 4585-116Portugal Biomedical Research Center Qatar UniversityDoha 2713Qatar Department of Biomedical Science College of Health SciencesQatar UniversityDoha 2713Qatar Department of Biology Chemistryand Environmental SciencesCollege of Arts and SciencesAmerican University of SharjahSharjah 26666United Arab Emirates Petroleum and Chemical Engineering Faculty of EngineeringUniversiti Teknologi BruneiBandar Seri Begawan BE1410Brunei Campus Straubing for Biotechnology and Sustainability Technical University of MunichStraubing 94315Germany Genetic Heritage Group New York UniversityAbu Dhabi 129188United Arab Emirates Bioinformatics Division NMC Genetics India Pvt.Ltd.Gurugram 122001India

Appropriate oral hygiene significantly reduces the possibility of oral ***,dental caries and periodontal diseases are major oral health issues causing chronic diseases due to poor oral ***,herbal compounds have gained interest in maintaining oral *** of burdock root(Arctium),noni fruit(Morinda citrifolia),and neem leaf(Azadirachta indica)are now used as intracanal medicaments in endodontics and *** amboinicus species and other plants produces essential oil likeβ-caryophyllene,p-cymene,andγ-terpinene can exhibit antibacterial activity;highlighting phytoconstituents plays a vital role in oral *** COVID-19 pandemic highlighted the importance of hygiene and sanitization,to curb *** cavity is among the gateways for virus entry into *** is a potential reservoir of SARS-CoV-2,and there is an increased risk of infection if there is any fissure in the *** enables entry of virus into the vascular system through gingival or periodontal pocket,possibly reaching lung periphery then to lung vessels by interacting with endothelial surface receptors triggering pulmonary vasoconstriction and lung damage due to endothelial *** review aims to draw attention to the possible route of SARS-CoV-2 infection via the oral cavity and the importance of oral hygiene against COVID-19.

关键词： COVID-19 SARS-CoV-2 Oral Hygiene Microbiota Phytochemicals

同方期刊数据库

Stabilizing Energy Consumption in Unequal Clusters of Wireless Sensor Networks

在线全文

学校读者我要写书评

暂无评论

Computers, Materials & Continua 2020年第7期64卷 81-96页

作者： Nithya Rekha sivakumar Department of Computer Sciences College of Computer and Information SciencesPrincess Nourah Bint Abdulrahman UniversityRiyadh11671Saudi Arabia

In the past few decades,Energy Efficiency(EE)has been a significant challenge in Wireless Sensor Networks(WSNs).WSN requires reduced transmission delay and higher throughput with high quality services,it further pays much attention in increased energy consumption to improve the network *** collect and transmit data Clustering based routing algorithm is considered as an effective *** Head(CH)acts as an essential role in network connectivity and perform data transmission and data aggregation,where the energy consumption is superior to non-CH *** clustering approaches attempts to cluster nodes of same ***,owing to randomly distributed node distribution,a cluster with equal nodes is not an obvious possibility to reduce the energy *** resolve this issue,this paper provides a novel,Balanced-Imbalanced Cluster Algorithm(B-IBCA)with a Stabilized Boltzmann Approach(SBA)that attempts to balance the energy dissipation across uneven clusters in WSNs.B-IBCA utilizes stabilizing logic to maintain the consistency of energy consumption among sensor nodes’.So as to handle the changing topological characteristics of sensor nodes,this stability based Boltzmann estimation algorithm allocates proper radius amongst the sensor *** simulation shows that the proposed B-IBCA outperforms effectually over other approaches in terms of energy efficiency,lifetime,network stability,average residual energy and so on.

关键词： WSN stability cluster head node balancing average residual energy

Strength Characteristics of Treated Soil with Proposed Layer Formation

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Journal of Wuhan University of Technology(Materials Science) 2023年第1期38卷 117-135页

作者： N sivakumar A Mandal Srinivasan venkatraman Department of Civil Engineering Visvesvaraya National Institute of TechnologyNagpur-440010India

The engineering characteristics of the soil,soil-fly ash and fly ash-lime,were examined to utilize as base layer material in civil *** influence of fly ash percentage and the effect of curing on California bearing ratio(CBR)and unconfined compressive strength(UCS),of soil and soil-fly ash mixing and layered system were examined to estimate the optimum *** volumetric swelling of the optimal mixture was estimated to be within the allowable *** microscope analysis and X-ray diffraction tests were performed.A model test analyses with three layers were conducted by finite element method and stress-strain behavior was observed.

关键词： Scanning electron microscopy simulation sustainable materials waste reduction X-ray diffraction

Lunar surface mineralogy using hyperspectral data： Implications for primordial crust in the Earth-Moon system

在线全文

学校读者我要写书评

暂无评论

Geoscience Frontiers 2017年第3期8卷 457-465页

作者： V. sivakumar Centre for Development of Advanced Computing (C-DAC) CDAC Innovation Park Pune 411008 India Department of Geology Periyar University Salem 636011 India Department of Industries and Earth Sciences Tamil University Tanjore 613010 India Centre for Tectonics Resources and Exploration Department of Earth Sciences University of Adelaide SA 5005 Australia School of Earth Sciences and Resources China University of Geosciences Belting 29 Xueyuan Road Beijing 100083 China Faculty of Science Kochi University Kochi 780-8520 Japan

Mineralogy of the Lunar surface provides important clues for understanding the composition and evo- lution of the primordial crust in the Earth-Moon system. The primary rock forming minerals on the Moon such as pyroxene, olivine and plagioclase are potential tools to evaluate the Lunar Magma Ocean （LMO） hypothesis. Here we use the data from Moon Mineralogy Mapper （M3） onboard the Chandrayaan- 1 project of India, which provides Visible/Near Infra Red （NIR） spectral data （hyperspectral data） of the Lunar surface to gain insights on the surface mineralogy. Band shaping and spectral profiling methods are used for identifying minerals in five sites： the Moscoviense basin, Orientale basin, Apollo basin, Wegener crater-highland, and Hertzsprung basin. The common presence of plagioclase in these sites is in conformity with the anorthositic composition of the Lunar crust. Pyroxenes, olivine and Fe-Mg-spinel from the sample sites indicate the presence of gabbroic and basaltic components. The compositional difference in pyroxenes suggests magmatic differentiation on the Lunar surface. Olivine contains OH/H20 band, indicating hydrous phase in the primordial magmas.

关键词： Moon Mineralogy Mapper Lunar Magma Ocean Primordial crust Magmatic differentiation Chandrayaan-1

Simple colorimetric detection of dopamine using modified silver nanoparticles

在线全文

学校读者我要写书评

暂无评论

Science China Chemistry 2016年第4期59卷 387-393页

作者： sivakumar Palanisamy Xuehua Zhang Tao He Key Laboratory of Nanosystem and Hierarchical Fabrication Chinese Academy of SciencesNational Center for Nanoscience and TechnologyBeijing 100190China University of Chinese Academy of Sciences Beijing 100049China

Dopamine(DA) plays an important role in health and peripheral nervous systems. Colorimetric detection of DA has the advantage of color change and simplicity in operation and instrumentation. Herein, we report a highly sensitive and selective colorimetric detection of DA by using two specific ligands modified Ag nanoparticles, where the DA molecules can make dual recognition with high specificity. The colloidal suspension of modified Ag nanoparticles was agglomerated after interacting with DA, while the color of Ag nanoparticles suspension changed from yellow to brown, arising from the interparticle plasmon coupling during the aggregation of Ag nanoparticles. The modified Ag nanoparticles suspension and agglomeration were confirmed by transmission electron microscope images. The optical properties behind the color change were thoroughly investigated by using UV-Vis and Raman techniques. The changes in p H, zeta potential, particle size and surface charge density by adding DA were also determined by using dynamic light scattering measurements. The detection limits of modified Ag probes for DA was calculated to be 6.13′10^(-6) mol L^(-1)(S/N=2.04) and the correlation co-efficient was determined to be 0.9878. Because of the simplicity in operation and instrumentation of the colorimetric method, this work may afford a feasible, fast approach for detecting and monitoring the DA levels in physiological and pathological systems.

关键词： dopamine detection Ag nanoprobe colorimetry dual molecular recognition sensitivity selectivity