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China Ocean Engineering 2014年第5期28卷 645-657页

作者： s.sakthivel murugan V.NATARAJAN K.MAHEsWARAN ECE Department SSN College of Engineering Instrumentation Department MIT Campus Anna University Infosys Chennai India

sonar generated acoustic signals transmitted in underwater channel for distant communications are affected by numerous factors like ambient noise, making them nonlinear and non-stationary in nature. In recent years, the application of Empirical Mode Decomposition(EMD) technique to analyze nonlinear and non-stationary signals has gained much attention. It is an empirical approach to decompose a signal into a set of oscillatory modes known as intrinsic mode functions(IMFs). In general, Hilbert transform is used in EMD for the identification of oscillatory signals. In this paper a new EMD algorithm is proposed using FFT to identify and extract the acoustic signals available in the underwater channel that are corrupted due to various ambient noises over a range of 100 Hz to 10 kHz in a shallow water region. Data for analysis are collected at a depth of 5 m and 10 m offshore Chennai at the Bay of Bengal. The algorithm is validated for different sets of known and unknown reference signals. It is observed that the proposed EMD algorithm identifies and extracts the reference signals against various ambient noises. significant sNR improvement is also achieved for underwater acoustic signals.

关键词： EMD IMF sNR ambient noises underwater acoustic signals FFT

A Complete Analysis of Clarity(C50)Using I-sIMPA to Maintain Ideal Conditions in an Acoustic Chamber

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sound & Vibration 2022年第1期56卷 51-64页

作者： R.Adithya Pillai s.sakthivel murugan Guruprasad Gupta Department of Electrical and Electronics Engineering Sri Sivasubramaniya Nadar College of EngineeringChennai603110India Department of Electronics and Communication Engineering Sri Sivasubramaniya Nadar College of EngineeringChennai603110India

In any closed environment considered,it can be seen that the acoustic parameters are inherently not constant over the entire area *** a closed environment,it is ideally preferred to maintain the acoustic parameters as constant so that there exists better quality of sound leading to better auditory perception with respect to the ***,some of the acoustic parameters like reverberation time and clarity do not strictly pertain to the pattern obtained *** this paper,simulations are carried out using I-sIMPA under different values of sound Transmission Class(sTC),source position,distribution and the chamber dimensions and provides an insight into the behaviour of these acoustic parameters and the appropriate values that have to be infused into the system to build the *** acoustic environment is modelled keeping an actual closed room in mind and testing is done with respect to different values of surface absorption coefficients(practically indicated using sound Transmission Class)and dimensions to determine ideal conditions.

关键词： Clarity C50 sound source surface receiver sound transmission class sTC surface absorption percentages

Does progress in microfracture techniques necessarily translate into clinical effectiveness?

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World Journal of Orthopedics 2024年第3期15卷 266-284页

作者： sathish Muthu Vibhu Krishnan Viswanathan Manoharan sakthivel Mohammed Thabrez Department of Orthopaedics Orthopaedic Research GroupCoimbatore 641045Tamil NaduIndia Department of Biotechnology Karpagam Academy of Higher EducationCoimbatore 641021Tamil NaduIndia Manoharan sakthivel Department of OrthopaedicsGovernment Medical CollegeKarur 639004Tamil NaduIndia Department of Orthopaedics Devadoss Multispecialty HospitalMadurai 625007Tamil NaduIndia Department of Medical Oncology Aster Medcity HospitalKochi 682034India

BACKGROUND Multitudinous advancements have been made to the traditional microfracture(MFx)technique,which have involved delivery of various acellular 2nd generation MFx and cellular MFx-III components to the area of cartilage *** relative benefits and pitfalls of these diverse modifications of MFx technique are still not widely *** To comparatively analyze the functional,radiological,and histological outcomes,and complications of various generations of MFx available for the treatment of cartilage *** A systematic review was performed using PubMed,EMBAsE,Web of science,Cochrane,and *** of any age and sex with cartilage defects undergoing any form of MFx were considered for *** included only randomized controlled trials(RCTs)reporting functional,radiological,histological outcomes or complications of various generations of MFx for the management of cartilage *** meta-analysis(NMA)was conducted in stata and Cochrane’s Confidence in NMA approach was utilized for appraisal of *** Forty-four RCTs were included in the analysis with patients of mean age of 39.40(±9.46)*** comparing the results of the other generations with MFX-I as a constant comparator,we noted a trend towards better pain control and functional outcome(KOOs,IKDC,and Cincinnati scores)at the end of 1-,2-,and 5-year time points with MFx-III,although the differences were not statistically significant(P>0.05).We also noted statistically significant Magnetic resonance observation of cartilage repair tissue score in the higher generations of microfracture(weighted mean difference:17.44,95%confidence interval:0.72,34.16,P=0.025;without significant heterogeneity)at 1 ***,the difference was not maintained at 2 *** was a trend towards better defect filling on MRI with the second and third generation MFx,although the difference was not statistically significant(P>0.05).CONCLUsION The higher generations of traditional MFx

关键词： Cartilage injury Microfracture Mesenchymal stem cells Platelet-rich plasma Bone marrow aspiration concentrates Clinical outcome Radiological outcome Meta-analysis Network meta-analysis

Exploring the electromagnetic shielding behavior of lanthanum doped calcium nanoferrites

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Journal of Rare Earths 2024年第11期42卷 2128-2136页

作者： E.Ahilandeswari K.sakthipandi R.Rajesh Kanna G.Rajkumar B.Ganesh Babu s.Arunmetha Aslam Hossain P.sakthivel V.Rajendran M.srinidhi Raghavan Department of Physics SRM TRP Engineering College Department of Electronics and Communication Engineering M. Kumarasamy College of Engineering Department of Physics Easwari Engineering College Department of Mechanical Engineering SRM TRP Engineering College Centre for Advanced Energy studies Department of Electronics and Communication EngineeringKoneru Lakshmaiah Education Foundation smart Materials Research Institute Southern Federal University Centre for Materials science Department of PhysicsScience and HumanitiesFaculty of EngineeringKarpagam Academy of Higher Education Centre for Nanotechnology Academy of Maritime Education and Training (Deemed to be University) Department of Chemistry and Centre for Nano-Materials and Displays B.M.S. College of Engineering

The present study focuses on the synthesis and characterization of lanthanum(La3+)-doped calcium nanoferrites(CaLaxFe2-xO4:x=0.025,0.050,0.075 and 0.100) using the sonochemical *** techniques were employed to analyze the effect of La3+infusion,Raman spectroscopy confirms the presence of active A1g,T2gand Egmodes in the CaLaxFe2-xO4nanoferrite,indicating the formation of an active ferrite *** introduction of La3+doping results in a significant increase in the band gap energy,rendering the nanoferrites insulating（3.23-3,57 eV）.At higher frequencies,the impedance studies reveal minimal losses and better AC conductivity,pointing to improved dielectric *** higher frequencies,the Q-factor of La-doped calcium nanoferrites shows lower electromagnetic *** M-H curve exhibits ferromagnetic behavior,with La3+-doped calcium nano ferrites displaying a saturation magnetization ranging from 12.72 to 18.10 emu/*** incorporation of La3+also induces enhanced electrical polarization,leading to notable dielectric loss and increased absorption of electromagnetic ***,these CaLaxFe2-xO4nanoferrites demonstrate potential as effective microwave absorbers across a wide frequency range,with significant shielding absorption observed at 8.8-9.1 GHz.

关键词： Dielectric Magnetism Microwave absorption Nanoferrites Rare earths structural properties

Influence of suspension stability on wet grinding for production of mineral nanoparticles

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Particuology 2008年第2期6卷 120-124页

作者： s.sakthivel Venkatesan V.Krishnan B.Pitchumani Particle science and Technology Laboratory Department of Chemical EngineeringIndian Institute of TechnologyNew DelhiIndia

Grinding behavior of nanoparticles in an attritor mill and the minimum achievable particle size are strongly influenced by the suspension stability. In the present work, suspension stability （i.e. ξ-potential） of nanoparticles was studied by measuring pH as a function of grinding time in the wet milling process. It was found that after a certain time in an attritor mill, there is no further size reduction and the average product particle size increases monotonically. One of the reasons is that the production of submicron particles leads to more particle-particle interactions and consequently pH of the suspension decreases with grinding time. Usually pH value is related to suspension stability and it can be enhanced by addition of NaOH solution. The maximum negative ξ-potential of -51.2 mV was obtained at pH of 12 for silica. The higher the ξ-potential with the same polarity, higher will be the electrostatic repulsion between the particles. Hence, the maximum electrostatic repulsion force was maintained by the adjustment ofpH value in wet milling. The experiments were conducted at different pH conditions which were maintained constant throughout the experiments and nanosized particles were obtained consequently.

关键词： suspension stability ξ-Potential Nanosilica particle Attritor mill

solid state synthesis of nano-mineral particles

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International Journal of Mining science and Technology 2012年第5期22卷 651-655页

作者： s.sakthivel R.Prasanna Venkatesh TCE QsTP-LLC Innovation CentreQatar Science and Technology ParkDoha 210000Qatar Department of Materials Engineering Hanyang UniversityAnsan 426791South Korea

Many researchers in academia and industries are interested in reducing particle sizes from few submicrometers to nano-meter *** nano-particles find application in several areas including ceramics,paints,cosmetics,microelectronics,sensors,textiles and biomedical,*** article reviews the present state of the art for solid state synthesis of mineral nano-particles by wet milling,including their operating variables such as ball size,solid mass fraction and suspension *** article concludes and recommends with a critical discussion of nano-particles synthesis and a few common strategies to overcome stability issues.

关键词： Vapor phase Liquid phase solid state Nano-particle suspension stability

Efficient Clustering Using Memetic Adaptive Hill Climbing Algorithm in WsN

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Intelligent Automation & soft Computing 2023年第3期35卷 3169-3185页

作者： M.Manikandan s.sakthivel V.Vivekanandhan Department of Computer science and Engineering Adhiyamaan College of EngineeringHosur635109TamilnaduIndia Department of Computer science and Engineering Sona College of TechnologySalem636005TamilnaduIndia

Wireless sensor Networks are composed of autonomous sensing devices which are interconnected to form a closed *** closed network is intended to share sensitive location-centric information from a source node to the base station through efﬁcient routing *** efﬁciency of the sensor node is energy bounded,acts as a concentrated area for most researchers to offer a solution for the early draining power of *** management plays a signiﬁcant role in wireless sensor networks,which was obsessed with the factors like the reliability of the network,resource management,energy-efﬁcient routing,and scalability of *** topology of the wireless sensor networks acts dri-ven factor for network efﬁciency which can be effectively maintained by perform-ing the clustering process *** solutions and clustering algorithms have been offered by various researchers,but the concern of reduced efﬁciency in the routing process and network management still *** research paper offers a hybrid algorithm composed of a memetic algorithm which is an enhanced version of a genetic algorithm integrated with the adaptive hill-climbing algorithm for performing energy-efﬁcient clustering process in the wireless sensor *** memetic algorithm employs a local searching methodology to mitigate the premature convergence,while the adaptive hill-climbing algorithm is a local search algorithm that persistently migrates towards the increased elevation to determine the peak of the mountain(i.e.,)best cluster head in the wireless sensor *** proposed hybrid algorithm is compared with the state of art clus-tering algorithm to prove that the proposed algorithm outperforms in terms of a network life-time,energy consumption,throughput,etc.

关键词： Wireless sensor networks topology clustering memetic algorithm adaptive hill climbing algorithm network management energy consumption throughput

Automated Irrigation system Using Improved Fuzzy Neural Network in Wireless sensor Networks

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Intelligent Automation & soft Computing 2023年第1期35卷 853-866页

作者： s.sakthivel V.Vivekanandhan M.Manikandan Department of Computer science and Engineering Sona College of TechnologySalem 636005TamilnaduIndia Department of Computer science and Engineering Adhiyamaan College of EngineeringHosur 635109TamilnaduIndia

Irrigation plays a significant role in various agricultural cropping methods deployed in semiarid and arid regions where valuable water applications and managing are considered crucial *** factors such as weather,soil,water,and crop data need to be considered for irrigation maintenance in an efficient besides uniform manner from multifaceted and different information-based systems.A Multi-Agent system(MAs)has been proposed recently based on diverse agent subsystems with definite objectives for attaining global MAs objective and is deployed on Cloud Computing paradigm capable of gathering information from Wireless sensor Networks(WsNs)positioned in rice,cotton,cassava crops for knowledge discovery and decision *** radial basis function network has been used for irrigation ***,in recent work,the security of data has not focused on where intruder involvement might corrupt the data at the time of data transferring to the cloud,which would affect the accuracy of decision *** handle the above mentioned issues,an efficient method for irrigation prediction is used in this *** factors considered for decision making are soil moisture,temperature,plant height,root *** above-mentioned data will be gathered from the sensors that are attached to the *** data will be forwarded to the local server,where data encryption will be performed using Adaptive Elliptic Curve Cryptography(AECC).After the encryption process,the data will be forwarded to the *** the data stored in the cloud will be decrypted key before being given to the deci-sion-making ***,the uniform distribution-based fuzzy neural network is formulated based on the received data information in the decisionmaking *** decision regarding the level of water required for cropfields would be *** on this outcome,the water volve opening duration and the level of fertilizers required will be *** results demons

关键词： Irrigation multi-agent system precision irrigation accuracy elliptic curve cryptography encryption wireless sensor networks fertilizers

Trends in mortality among the geriatric population undergoing surgical aortic valve replacement (sAVR) and potential racial disparities: a 20-year perspective via the National (Nationwide) Inpatient sample

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Journal of Geriatric Cardiology 2024年第7期21卷 716-722页

作者： Nomesh Kumar Kamleshun Ramphul FNU Bawna Nitish Behary Paray Mansimran si-ngh Dulay Jasninder singh Dhaliwal shruti Aggarwal sebastian Mactaggart suma sri Chennapragada shaheen sombans Renuka Verma Hemamalini sakthivel Raheel Ahmed Department of Internal Medicine Detroit Medical Center Sinai Grace-Wayne State UniversityMichiganUSA In-dependent Researcher TrioletMauritius Independent researcher Farmington HillsMichiganUSA Royal Devon University Healthcare NHs Foundation Trust ExeterUnited Kingdom Royal Brompton Hospital part of Guy’s and St.Thomas’NHS Foundation TrustLondonUnited Kingdom Department of Internal Medicine University of Cali-forniaRiversideUSA Independent Researcher New DelhiIndia Northumbria Hospitals NHs Foundation Trust NewcastleUnited Kingdom Department of Internal Medicine Louisiana State UniversityShreveportUSA sha-heen sombans Independent ResearcherHyderabadIndia Department of Internal Medicine Kirk Kerkorian School of Medicine at UNLVLas VegasUSA One Brooklyn Health system/Interfaith Medical Ctr Program BrooklynNYUSA

Background Racial disparities in cardiovascular conditions are well *** similar race-based discrepancies in health outcomes also exist among elderly patients undergoing surgical aortic valve replacement(sAVR) for aortic stenosis remains *** We abstracted data from the National(Nationwide) Inpatient sample over a 20-year period from 2001 to 2020 using specific ICD-9 and ICD-10 *** included patients aged ≥ 60 and ≤ 80 years with races recorded as White,African American,or Hispanic at the time of their hospitalization for *** analyzed and reported the baseline characteristics,risk-adjusted inhospital mortality,and complications stratified by *** Of 420,181 patients studied,90.0% identified as White,4.0% as African American and 6.0% as *** a decrease in overall in-hospital mortality rates from 3.8% between 2001-2005 to 1.8% between 2016-2020,African Americans had higher odds of all-cause in-hospital deaths compared to Whites(a OR = 1.390,P shock(a OR = 1.241,P s well as more likely to require organ support such as IABP use(a OR = 1.336,P sive mechanical ventilation(a OR = 1.342,P stingly,African Americans were less likely to report events of acute ischemic stroke compared to Whites(a OR = 0.852,P sions Despite a reassuring reduction in overall in-hospital mortality rates of geriatric patients undergoing sAVR for aortic stenosis,racial disparities in health outcomes remain pervasive with minorities more likely to report higher in-hospital morbidity and mortality.

关键词： mortality likely spite

Detection and clearance in Alzheimer’s disease: leading with illusive chemical, structural and morphological features of the targets

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Neural Regeneration Research 2024年第3期19卷 497-498页

作者： Luís Gales i3s−Instituto de Investigação e Inovação em saúde Rua Alfredo AllenPortoPortugal(Gales L)IBMC−Instituto de Biologia Molecular e CelularUniversidade do PortoRua Alfredo AllenPortoPortugal ICBAs−Instituto de Ciências Biomédicas Abel salazar Rua de Jorge Viterbo FerreiraPortoPortugal

Highly specific interactions between biomolecules,such as antigen-antibody,protein-ligand,or nucleic acid base pair complementary are on the basis of the organization of complex *** same principles may be tentatively used in molecular medicine for diagnosis and therapeutics.A molecule can be designed to selectively bind a protease and thereby inhibit the production of a peptide that forms toxic aggregates in the brain or an antibody may be produced to bind specifically to that peptide for detection or clearance ***,interference in biological systems is not that *** a start there is the inhibition of the physiological role of the protease;moreover,several cleavage fragments may be produced,which may continue to diverge due to putative post-translational modification and self-assembly processes,hiding the toxic target in a“soup”of peptide species varying in size,structure and chemical composition.A perspective of the current status and challenges in targeting peptide species for diagnosis and treatment in the context of Alzheimer’s disease is given.

关键词： Alzheimer diagnosis thereby