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Biomimetic flexible plate actuators are faster and more efficient with a passive attachment

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Acta Mechanica Sinica 2016年第6期32卷 1001-1011页

作者： Peter d.yeh Alexander Alexeev George W.Woodruff School of Mechanical Engineering Georgia Institute of Technology

Using three-dimensional computer simulations, we probe biomimetic free swimming of an internally actuated flexible plate in the regime near the first natural frequency. The plate is driven by an oscillating internal moment approximating the actuation mechanism of a piezoelectric macro fiber composite (MFC) bimorph. We show in our simulations that the addition of a passive attachment increases both swimming velocity and efficiency. Specifically, if the active and passive sections are of similar size, the overall performance is the best. We determine that this optimum is a result of two competing factors. If the passive section is too large, then the actuated portion is unable to generate substantial deflection to create sufficient thrust. On the other hand, a large actuated section leads to a bending pattern that is inefficient at generating thrust especially at higher frequencies.

关键词： Flexible plate Biomimetic Lattice Boltzmann Fluid-structure interaction Robotic fish Piezoelectric actuator

Core Shell Au Ag Nanoparticles in dielectric Nanocomposites with Plasmon-Enhanced Fluorescence: A New Paradigm in Antimony Glasses

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Nano Research 2009年第8期2卷 607-616页

作者： Tirtha som Basudeb Karmakar Glass Technology Laboratory Glass DivisionCentral Glass and Ceramic Research Institute(Council of Scientifi c and Industrial Research)196Raja S.C.Mullick RoadKolkata 700032India

The nano era demands the synthesis of new nanostructured materials,if possible by simplified techniques,with remarkable properties and versatile ***,we demonstrate a new single-step reproducible melt-quench methodology to fabricate core-shell bimetallic(Au0 Ag0)nanoparticles(2889 nm)embedded glasses(dielectrics)by the use of a new reducing glass matrix,K_(2)O B_(2)O_(3) Sb_(2)O_(3)(KBS)without applying any external reducing agent or multiple processing *** surface plasmon resonance(SPR)band of these nanocomposites embedded in KBS glass is tunable in the range 554-681 *** remarkably,taking advantage of the selective reduction capability of Sb_(2)O_(3),this single-step methodology is used to fabricate inter-metallic:rare-earth ions co-embedded(AuAg:Sm^(3+))dielectric(glass)-based-dnanocomposites and study the effect of enhanced local fi eld on the red upconversion fl uorescence of Sm^(3+)ions at 636 *** enhancement is found to be about 2 *** single-step in-situ selective reduction approach can be used to fabricate a variety of hybrid-nanocomposite devices for laser based applications(see supplementary information).

关键词： Gold-silver nanostructures core-shell morphology surface plasmon resonance antimony glass metal-enhanced rare earth fl uorescence

A multicountry comparison of cryptocurrency vs gold: Portfolio optimization through generalized simulated annealing

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Blockchain(Research and Applications) 2022年第3期3卷 23-35页

作者： Ankit som Parthajit Kayal Madras School of Economics Chennai600025India

The last few years have seen a paradigm shift in the financial sector with the development of cryptocurrencies as an alternative mode of payment as well as an investment *** aim of this study is *** first is to quantify the volatility of cryptocurrencies in terms of the dynamics of tail-end behavior using different approaches and choose the one with the lowest *** second is to investigate the effect of its inclusion in a portfolio with and without gold,to see if Bitcoin is indeed the“digital gold”.This paper uses the generalized simulated annealing optimization technique to compare portfolios for ten countries across the *** data provide convincing evidence in favor of the inclusion of Bitcoin in the optimized ***-window analyses(three-year and five-year)confirm the ***,for some countries,the empirical pattern suggests that instead of replacing gold from the portfolio,both should be *** results are robust in terms of the inclusion of non-linear constraints.

关键词： Cryptocurrency Gold Value-at-risk Portfolio optimization Generalized simulated annealing

Hill slope instability of Nainital City,Kumaun Lesser Himalaya,Uttarakhand,India

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Journal of Rock Mechanics and Geotechnical Engineering 2018年第2期10卷 280-289页

作者： Nirvan Sah Mohit Kumar Rajeev Upadhyay som dutt department of Geology(CAS) Kumaun UniversityNainital263001India Wadia Institute of Himalayan Geology 33 General Mahadeo Singh RoadDehradun248001India

Nainital City of Kumaun Lesser Himalaya is prone to mass wasting processes during monsoon season,which mischievously triggers the hill slope instability in this region. Slate, dolomitic limestone, silty sandstone and rhythmite of the Krol Formation are the main rock types. The present study focuses on the investigation of slope stability in the region in terms of potential seismicity and landslide. Geological and geotechnical mapping indicates that the major portion of the area is characterized by slope wash materials and buildings. The combination of 3-4 joint sets with one random joint is the main structure at *** major geological structures of this area are Nainital lake fault passing from the center of the lake, Main Boundary Thrust at SW, and Khuriya Fault passing from the SE direction of Nainital City. This work finds that different types of discontinuities(e.g. joints and faults), overburden due to unplanned civil structures,and neotectonic activity in the vicinity of this ara affect the stability of the city. The slate forms the base of the city, dipping slightly towards the lake side along the NW direction, thus accelerating the instability of this area. Rock mass rating(RMR), slope mass rating, factor of safety(FOS) and graphical analysis of the discontinuity for slope kinematics indicate that the study area is a landslide-prone zone. This study can facilitate reducing the risk of human life, and contribute to the ongoing construction works in the area.

关键词： Hill slope instability Himalaya region Wedge failure Rock mass rating(RMR) Factor of safety(FOS)

Analysis of the current density characteristics in through-mask electrochemical micromachining(TMEMM) for fabrication of micro-hole arrays on invar alloy film

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Chinese Journal of Aeronautics 2017年第3期30卷 1231-1241页

作者： da-som JIN Kwang-ho CHUN Eun-sang LEE School of Mechanical Engineering Inha University Incheon 22212 Republic of Kore department of Mechanical Engineering Inha University Incheon 22212 Republic of Korea

Invar alloy consisting of 64% iron and 36% nickel has been widely used for the production of shadow masks for organic light emitting diodes（OLEds） because of its low thermal expansion coefficient（1.86 × 10^-6cm/°C）.To fabricate micro-hole arrays on 30 lm invar alloy film,through-mask electrochemical micromachining（TMEMM） was developed and combined with a portion of the photolithography etching *** precise hole shapes,patterned photoresist（PR） film was applied as an insulating *** investigate the relationship between the current density and the material removal rate,the principle of the electrochemical machining was studied with a focus on the *** finite element method（FEM） was used to verify the influence of each parameter on the current density on the invar alloy film *** parameters considered were the thickness of the PR mask,inter-electrode gap（IEG）,and electrolyte *** of experiments（dOE） was used to figure out the contribution of each parameter.A simulation was conducted with varying parameters to figure out their relationships with the current *** was conducted to select the suitable *** experiment was carried out to verify the simulation *** was possible to fabricate micro-hole arrays on invar alloy film using TMEMM,which is a promising method that can be applied to fabrications of OLEds shadow masks.

关键词： Electrochemical Invar alloy film Micromachining OLEd shadow mask Photoresist film mask(PR film mask) Through-mask electrochemical micromachining(TMEMM)

Capillary Electrophoresis for the Simultaneous determination of Metals by Using Ethylenediamine Tetraacetic Acid as Complexing Agent and Vancomycin as Complex Selector

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Chinese Journal of Chemistry 2006年第12期24卷 1747-1753页

作者： THREEPROM Jirasak som-AUM Waraporn 林金明 The Key Laboratory of Bioorganic Phosphorus Chemistry & Chemical Biology department of Chemistry Tsinghua University Beijing 100084 China department of Chemistry Faculty of Science Mahasarakham University Mahasarakham 44150 Thailand

A new separation system of capillary electrophoresis for the simultaneous determination of metals by using ethylenediamine tetraacetic acid （EdTA） as complexing agent and employing vancomycin as complex selector was described. The Z-shape cell capillary electrophoresis was used to enhance the sensitivity for the determination of the complexes of Cu（Ⅱ）, Ni（Ⅱ）, Co（Ⅱ） and Fe（Ⅲ） with EdTA. The partial filling method （co-current mode） was used in order to increase the selectivity of the electrophoretic method, meanwhile vancomycin was not present at the detector path during the detection of metal-EdTA complexes. The vancomycin concentration, phosphate concentration and pH of the buffer strongly influenced mobility, resolution and selectivity of the studied analytes. Under the optimal condition, the relative standard deviations （n=5） of the migration time and the peak area were less than 3.14% and 7.35%, respectively. Application of the Z-shape cell capillary electrophoresis method with UV detection and vancomycin loading led to the reliable determination of these metal ions in tap water and the recoveries were 97%-101%. The detection limits based on a signal to noise ratio of 3 ： 1 were found in the range of 2-10 μg·L^-1.

关键词： Z-shape cell capillary electrophoresis vancomycin metal ion ethylenediamine tetraacetic acid

Economic analysis of a hybrid solar-fuel cell power delivery system using tuned genetic algorithm

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Frontiers in Energy 2012年第1期6卷 12-20页

作者： Trina som Niladri CHAKRABORTY Power Engineering department Jadavpttr UniversityKolkata 700098India

An economic evaluation of a network of distributed energy resources （dERs） comprising a microgrid structure of power delivery system in an Indian scenario has been made. The mathematical analysis is based on the application of tuned genetic algorithm （TGA）. The analyses for optimal power operation pertaining to minimum cost have been made for two cases in Indian power delivery system. The first case deals with the consumers＇ individual optimal operation of dERs, while in the second one, consumers altogether form a microgrid with the optimal supply of power from dERs. The total annual costs for these two cases are found to be economically competitive and encouraging. A reduction of approximately 5.7% in the annual cost has been obtained in the case of microgid system than that in the separately operating consumers＇ system for a small locality of India. It is observed that the application of TGA results in a reduction of the minimum cost depicting an improved outcome in terms of energy economy.

关键词： distributed energy resources (dERs) microgrid tuned genetic algorithm (TGA)

COVId-19 rhapsody:Rage towards advanced diagnostics and therapeutic strategy

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Journal of Pharmaceutical Analysis 2021年第5期11卷 529-540页

作者： Koel Sinha Sutapa som Chaudhury Pramita Sharma Bhuban Ruidas Centre for Healthcare Science and Technology Indian Institute of Engineering Science TechnologyShibpurHowrah711103India department of Zoology Hooghly Mohsin College Affiliated to University of BurdwanHooghly712101India

The deadly global outbreak of coronavirus disease-2019(COVId-19)has forged an unrivaled threat to human *** its profuse impact,initial risk management and therapies are needed,as well as rapid detection strategies alongside treatments with existing drugs or traditional treatments to provide better clinical support for critical *** detection techniques have been considered but do not sufficiently meet the current challenges of effective COVId-19 ***,several modern techniques including point-of-care diagnosis with a biosensor,clustered regularly interspaced short palindromic repeats(CRISPR)-associated proteins that function as nuclease(Cas)technology,next-generation sequencing,serological,digital,and imaging approaches have delivered improved and noteworthy success compared to that using traditional *** drug treatment,plasma therapy,and vaccine development are also ***,alternative medicines including Ayurveda,herbal drugs,homeopathy,and Unani have also been enlisted as prominent treatment strategies for developing herd immunity and physical defenses against *** considered,this review can help develop rapid and simplified diagnostic strategies,as well as advanced evidencebased modern therapeutic approaches that will aid in combating the global pandemic.

关键词： COVId-19 Ayurveda Herd immunity Homeopathy

On the number of matchings of graphs formed by a graph operation

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Science China Mathematics 2006年第10期49卷 1383-1391页

作者： yeh Yeong-Nan Institute of Mathematics Academia Sinica

Let G be a simple graph. define R(G) to be the graph obtained from G by adding a new vertex e* corresponding to each edge e = (a, b) of G and by joining each new vertex e* to the end vertices a and b of the edge e corresponding to it. In this paper, we prove that the number of matchings of R(G) is completely determined by the degree sequence of vertices of G.

关键词： matching, Hosoya index, matching polynomial, oriented incident matrix,skew adjacency matrix.