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Shear deformable finite beam elements for composite box beams

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Acta Mechanica Sinica 2014年第2期30卷 223-240页

作者： nam-Il Kim Dong-Ho Choi Department of Architectural Engineering Sejong University Department of Civil and Environmental Engineering Hanyang University

The shear deformable thin-walled composite beams with closed cross-sections have been developed for coupled flexural, torsional, and buckling analyses. A theoretical model applicable to the thin-walled laminated composite box beams is presented by taking into account all the structural couplings coming from the material anisotropy and the shear deformation effects. The current composite beam includes the transverse shear and the restrained warping induced shear deformation by using the first-order shear deformation beam theory. Seven governing equations are derived for the coupled axial-flexural-torsional-shearing buckling based on the principle of minimum total potential energy. Based on the present analytical model, three different types of finite composite beam elements, namely, linear, quadratic and cubic elements are developed to analyze the flexural, torsional, and buckling problems. In order to demonstrate the accuracy and superiority of the beam theory and the finite beam elements developed by this study,numerical solutions are presented and compared with the results obtained by other researchers and the detailed threedimensional analysis results using the shell elements of ABAQUS. Especially, the influences of the modulus ratio and the simplified assumptions in stress-strain relations on the deflection, twisting angle, and critical buckling loads of composite box beams are investigated.

关键词： Thin-walled Composite box beam Deflection Twisting angle Buckling load Shear deformation

Recent progress in production and usage of hydrogen peroxide

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Chinese Journal of Catalysis 2021年第8期42卷 1241-1252页

作者： Shunichi Fukuzumi Yong-Min Lee Wonwoo nam Department of Chemistry and Nano Science Ewha Womans UniversitySeoul 03760Korea Graduate School of Science and Engineering Meijo UniversityNagoyaAichi 468-8502Japan Research Institute for Basic Sciences Ewha Womans UniversitySeoul 03760Korea

Hydrogen peroxide has attracted increasing interest as an environmentally benign and green oxidant that can also be used as a solar fuel in fuel *** review focuses on recent progress in production of hydrogen peroxide by solar-light-driven oxidation of water by dioxygen and its usage as a green oxidant and *** photocatalytic production of hydrogen peroxide is made possible by combining the e^(-)and 4e-oxidation of water with the e^(-)reduction of dioxygen using solar *** catalytic control of the selectivity of the e^(-)vs.4e-oxidation of water is discussed together with the selectivity of the e^(-)vs.4e-reduction of *** combination of the photocatalytic e^(-)oxidation of water and the e^(-)reduction of dioxygen provides the best efficiency because both processes afford hydrogen *** solar-light-driven hydrogen peroxide production by oxidation of water and by reduction of dioxygen is combined with the catalytic oxidation of substrates with hydrogen peroxides,in which dioxygen is used as the greenest oxidant.

关键词： Hydrogen peroxide production Water oxidation Dioxygen reduction Photocatalytic oxygenation Reaction kinetics and mechanism

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A New Duplex Reverse Transcription PCR for Simultaneous Detection of Viable Cryptosporidium parvum Oocysts and Giardia duodenalis Cysts

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Biomedical and Environmental Sciences 2010年第2期23卷 146-150页

作者： SEHEE nam GYUCHEOL LEE Water Analysis and Research Center K-water Daejeon 306-711 Republic of Korea

Objective To simultaneously detect viable Cryptosporidium parvum oocysts and Giardia duodenalis cysts for the purpose of reducing time and cost spent. Methods A duplex reverse transcription polymerase chain reaction （RT-PCR） method was newly developed. Results Using duplex RT-PCR method for the hsp70 gene, viable （oo）cyst concentrations of 10^1 and l0^3 （oo）cysts/100 *** could be detected for C. parvum and G duodenalis, respectively. However, after heat-shock stimulation the expression of hsp70 mRNAs was detectable at 10^0 and 10^1 （oo）cysts/100 μL concentrations of C. parvum and G. duodenalis, respectively. Thus, the detection sensitivity was significantly increased when the viable （oo）cysts were exposed to heat shock. Conclusion This study describes a new duplex RT-PCR method for hsp70 gene to detect the viable （oo）cysts of the C. parvum and G duodenalis with less time consumed and at a lower cost. This newly developed duplex RT-PCR method may be used to detect these parasites not only in aquatic environments but also in clinical samples.

关键词： Cryptosporidiumparvum Giardia duodenalis Heat-shock RT-PCR

Ameliorating effect of Zhizi(Fructus Gardeniae) extract and its glycosides on scopolamine-induced memory impairment

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Journal of Traditional Chinese Medicine 2013年第2期33卷 223-227页

作者： Youngjoo nam Dongung Lee Division of Bioscience Dongguk UniversityGyeongju 780-714Republic of Korea

OBJECTIVE： To study the chemical constituents of Zhizi （Fructus Gardeniae） and their antiamnesic ef- fect in a mouse model of Alzheimer＇s disease. METHODS： Ameliorating effects of the extracts, fractions and constituents on scopolamine-in- duced memory impairment in vivo using a passive avoidance task system and their inhibitory activi- ties on acetylcholinesterase （ACHE） in vitro were ex- amined. The isolation of components was per- formed by chromatographic techniques and their structures were identified on the basis of spectral analysis. RESULTS： Activity-guided fractionation of the total extracts resulted in the isolation of two glycosides, geniposide and cr0cin from the n-butanol fraction and genipin and crocetin from the ethylacetate fraction. Among the fractions tested, n-butanol fraction showed the strongest AChE inhibition （43.4% at a final dose of 0.03 mg/mL） and also ex- hibited outstanding efficacy （65.9% at a dose of2.50 mg/kg） in an experimental model of amnesia. Geniposide showed a 22.8% AChE inhibitory activi- ty and a potent ameliorating effect on scopol- amine-induced memory impairment in amnesic mice of 93.4% as compared to the control group. CONCLUSION： Geniposide, a main constituent of gardenia should be considered a candidate for fur- ther clinical study for the purpose of developing a cognition activator and its mechanism of action may be mediated, at least in part, by the acetylcho- line enhancing cholinergic nervous system.

关键词： Gardenia Acetylcholinesterase AI-zheimer disease Geniposide Passive avoidancetask

Simulation of wind-induced near-inertial oscillations in a mixed layer near the east coast of Korea in the East/Japan Sea

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Acta Oceanologica Sinica 2013年第9期32卷 11-20页

作者： nam SungHyun PARK Young-Gyu Naval Systems Development Center Agency for Defense Development Ocean Circulation and Climate Research Division Korea Institute of Ocean Science and Technology

Using a simple damped slab model, it was possible to show that a local wind induced 88% （15 of 17） of the near-inertial oscillations （NIO） observed in the mixed layer near the east coast of Korea from 1999 to 2004. The model, however, overestimated the energy level in about two-thirds of the simulated cases, because the slab model was forced with winds whose characteristic period was shorter than the damping time scale of the model at 1.5 d. At the observation site, due to typhoons and orographic effects, high-frequency wind forcing is quite common, as is the overestimation of the energy level in the slab model results. In short, a simple slab model with a damping time-scale of about 1.5 d would be enough to show that the local wind was the main energy source of the near-inertial energy in this area, but the model could not be used to accurately estimate the amount of the work done by the wind to the mixed layer.

关键词： near-inertial oscillations near-inertial waves slab model high-frequency wind forcing eastcoast of Korea

Suppression of gold nanoparticle agglomeration and its separation via nylon membranes

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Chinese Journal of Chemical Engineering 2017年第7期25卷 931-937页

作者： Ayyavoo Jayalakshmi In-Chul Kim Young-nam Kwon School of Urban and Environmental Engineering Ulsan National Institute of Sdence and TechnologyUlsan 689-798Korea KIST-UNIST UIsan Center for Convergent Materials UNIST(Ulsan National Institute of Science and Technology)Korea Environment and Resources Research Center Korea Research Institute Chemical TechnologyDaejeon 305-606Korea

Use of ultraporous nylon membrane is one of the most widely employed techniques for removal of hard and soft nanoparticles in the semiconductor industry, and the accurate determination of membrane pore size is necessary in order to avoid manufacturing defects caused by contamination. The gold nanoparticle has several benefits for the evaluation of polymeric membranes; however, the nanoparticles agglomerate easily on the nylon membrane and make it difficult to evaluate the membrane precisely. The properties of 2-amino-2-hydroxymethyl-1,3-propanediol(ADP) ligand in gold nanoparticle solution were systematically investigated, and ADP was utilized for improved evaluation of the nylon membranes. Nylon membrane used in this study was prepared by phase inversion techniques. Ultrathin dense layer on top of the membrane surface and Darcy structures in the microporous membrane support were observed. The gold particle rejection was carried out at various p H values from 4 to14 and higher rejection was observed at p H 4 and 8. The suppression of gold colloid agglomeration using ADP and monodispersity of gold colloids was also analyzed by confocal laser scanning microscopy(CLSM), transmission electron microscopy(TEM), and scanning electron microscopy(SEM). van der Waals interaction energy of the particles was reduced in the addition of ADP. The presence of ADP ligand in the gold solutions prevented the agglomeration of gold nanoparticles and reduced the adsorption of the particles on the nylon membrane surface,leading to precise evaluation of membrane pore sizes.

关键词： Particle size Electron microscopy Gold colloid flock Semiconductor

Efficient Network Selection Using Multi-Depot Routing Problem for Smart Cities

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Intelligent Automation & Soft Computing 2023年第5期36卷 1991-2005页

作者： R.Shanthakumari Yun-Cheol nam Yunyoung nam Mohamed Abouhawwash Department of Information Technology Kongu Engineering CollegePerundurai638060India Department of Architecture Joongbu UniversityGoyang10279Korea Department of ICT Convergence Soonchunhyang UniversityKorea Department of Mathematics Faculty of ScienceMansoura UniversityMansoura35516Egypt Department of Computational Mathematics Scienceand Engineering(CMSE)Michigan State UniversityEast LansingMI48824USA

Smart cities make use of a variety of smart technology to improve societies in better *** intelligent technologies,on the other hand,pose sig-niﬁcant concerns in terms of power usage and emission of *** suggested study is focused on technological networks for big data-driven *** the support of software-deﬁned technologies,a transportation-aided multicast routing system is *** using public transportation as another communication platform in a smart city,network communication is *** primary objec-tive is to use as little energy as possible while delivering as much data as *** Attribute Decision Making with Capacitated Vehicle(CV)Routing Problem(RP)and Half Open Multi-Depot Heterogeneous Vehicle Routing Problem is used in the proposed *** the optimum network selection,a Multi-Attribute Decision Making(MADM)method is *** the sake of reducing energy usage,the Capacitated Vehicle Routing Problem(CVRP)is *** reduce the transportation cost and risk,Half Open Multi-Depot Heterogeneous Vehicle Routing Problem is ***,a mixed-integer programming approach is used to deal with the *** produce Pareto optimal solutions,an intelligent algorithm based on the epsilon constraint approach and genetic algorithm is cre-ated.A scenario of Auckland Transport is being used to validate the concept of ofﬂoading the information onto the buses for energy-efﬁcient and delay-tolerant data *** the experiments have demonstrated that the buses may be used effectively to carry out the data by customer requests while using 30%of less energy than the other systems.

关键词： Smart cities data ofﬂoading energy consumption bi-objective capacitated vehicle routing problem public transportation big data

AN ENSEMBLE MODEL OF ARIMA AND ANN WITH RESTRICTED BOLTZMANN MACHINE BASED ON DECOMPOSITION OF DISCRETE WAVELET TRANSFORM FOR TIME SERIES FORECASTING

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Journal of Systems Science and Systems Engineering 2018年第5期27卷 690-708页

作者： Warut Pannakkong Songsak Sriboonchitta Van-nam Huynh School of Manufacturing Systems and Mechanical Engineering Sirindhorn International Institute of TechnologyThammasat University Pathumthani 12121 Thailand Faculty of Economics Chiang Mai University Chiang Mai 52000 Thailand School of Knowledge Science Japan Advanced Institute of Science and Technology Nomi 923-1292 Japan

Time series forecasting research area mainly focuses on developing effective forecasting models toimprove prediction accuracy. An ensemble model composed of autoregressive integrated movingaverage （ARIMA）, artificial neural network （ANN）, restricted Boltzmann machines （RBM）, anddiscrete wavelet transform （DWT） is presented in this paper. In the proposed model, DWT firstdecomposes time series into approximation and detail. Then Khashei and Bijari＇s model, which is anensemble model of ARIMA and ANN, is applied to the approximation and detail to extract their bothlinear and nonlinear components and fit the relationship between the components as a function insteadof additive relationship. Furthermore, RBM is used to perform pre-training for generating initialweights and biases based on inputs feature for ANN. Finally, the forecasted approximation and detailare combined to obtain final forecasting. The forecasting capability of the proposed model is testedwith three well-known time series： sunspot, Canadian lynx, exchange rate time series. The predictionperformance is compared to the other six forecasting models. The results indicate that the proposedmodel gives the best performance in all three data sets and all three measures （i.e. MSE, MAE andMAPE）.

关键词： Time series forecasting autoregressive integrated moving average (ARIMA) artificial neural network (ANN) discrete wavelet transform (DWT) restricted Boltzmann machine (RBM)

Reliability, Accuracy, and Use Frequency of Evaluation Methods for Amount of Tongue Coating

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Chinese Journal of Integrative Medicine 2019年第5期25卷 378-385页

作者： Su-Ryun Kim Dong-Hyun nam Department of Biofunctional Medicine and Diagnosis College of Korean MedicineSangji UniversityWonju 26339Republic of Korea

Objective: To classify the evaluation methods for amount of tongue coating(TC) and investigate their reliability, accuracy, and frequency of use. Methods: Articles published from 1985 to 2015 were searched for evaluation methods for the amount of TC in PubMed and the Cochrane Library. Only clinical researches were included except protocol articles. The methods were classi?ed according to their characteristics. Results: Finally,113 articles were selected. The evaluation method for the amount of TC from the articles was classi?ed into 4 types: intuitive, specificative, computerized, and weighing TC. The reliability in the intuitive and specificative methods(κ=0.33–0.92) showed varying levels among the studies. In general, the amount of TC calculated by the speci?cative method(Spearman's r=0.68–0.80) was more strongly related to the directly measured value than to the value estimated by the computerized method(Pearson's r=0.442). The number of articles published on this topic has increased consistently, and the speci?cative method was the most frequently used. Despite the higher reliability of the computerized method, it has not been widely used. Conclusions: The high prevalence of the speci?cative method would continue in clinical practice because of its convenience and accuracy. However,to establish higher reliability, the limitation of the subjectivity of the assessors should be overcome through calibration training. In the computerized method, novel algorithms are needed to obtain a higher accuracy so that it can help the practitioners con?dently estimate the amount of TC.

关键词： tongue coating evaluation methods reliability accuracy frequency