• Advances in nano research
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• v.17 no.3
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• pp.257-274
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• 2024

This work aims to study and analyse the dynamic size dependent behvior of functionally graded carbon nanotubes (FGCNTs) nanoplates embedded in elastic media and subjected to moving point load. The non-classical effect is incorporated into the governing equations using the nonlocal strain gradient theory (NSGT). Four different reinforcement configurations of the carbon nanotubes (CNTs) are considered to show the effect of reinforcement configuration on the dynamic behvior of the FGCNTs nanoplates. The material characteristics of the functionally graded materials are assumed to be continuously distributed throughout the thickness direction according to the power law. The Hamiltonian principle is exploited to derive the dynamic governing equations of motion and the associated boundary conditions in the framework of the first order shear deformation plate theory. The Navier analytical approach is adopted to solve the governing equations of motion. The obtained solution is checked by comparing the obtained results with the available results in the literature and the comparison shows good agreement. Numerical results are obtained and discussed. Obtained results showed the significant impact of the elastic foundation parameters, the non-classical material parameters, the CNT configurations, and the volume fractions on the free and forced vibration behaviors of the FGCNT nanoplate embedded in two parameters elastic foundation and subjected to moving load.

• Transactions of the Korean Society of Mechanical Engineers B
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• v.33 no.9
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• pp.688-698
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• 2009

Using the multi-dimensional, multi-phase, nonisothermal Polymer Electrolyte Fuel Cell (PEFC) model presented in Part I, the effects of land/channel flow-field on temperature and liquid saturation distributions inside PEFCs are investigated in Part II. The focus is placed on exploring the coupled water transport and heat transfer phenomena within the nonisothermal and two-phase zone existing in the diffusion media (DM) of PEFCs. Numerical simulations are performed varying the land and channel widths and simulation results reveal that the water profile and temperature rise inside PEFCs are considerably altered by changing the land and channel widths, which indicates that oxygen supply and heat removal from the channel to the land regions and liquid water removal from the land toward the gas channels are key factors in determining the water and temperature distributions inside PEFCs. In addition, the adverse liquid saturation gradient along the thru-plane direction is predicted near the land regions by the numerical model, which is due to the vapor-phase diffusion driven by the temperature gradient in the nonisothermal two-phase DM where water evaporates at the hotter catalyst layer, diffuses as a vapor form and then condenses on the cooler land region. Therefore, the vapor phase diffusion exacerbates DM flooding near the land region, while it alleviates DM flooding near the gas channel.

• Journal of Embryo Transfer
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• v.10 no.3
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• pp.251-256
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• 1995

This study was experimented that developmental effects of bovine in vitro fertilized embryos by coculture system and supplementation of energy materials into simple media. With the ovaries from slaughter house in vitro maturation by 24h, in vitro fertilization was performed with sperms collected by Percoll gradient method. Fertilized embryos were cocultured in 15% FCS+CZB medium with BOEC(bovine oviductal epithelial cell), GCM (granulosa cell monolayer) and MEFC(mouse embryonic fihrohlast cell). And also in this study, there was trying to improve the early developmental rate of embryos by addition of concentration-controlled Na-pyruvate, D-glucose which were used as energy sources into CZB medium. In vitro developmental rate was confirmed by the cleavage rate of 48h post-IVF and the embryo development rate at 240h culture. In the coculture system BOEC had 20.0% of blastocysts rate, which was higher than that of other coculture systems. To determine the optimum concentration for early embryo developmental rate rapidly, through the gradient of concentrations of Na-pyruvate and D-glucose, we focused on the cleavage rate at 48h and blastocysts rate at 240h. In case of Na-pyruvate, cleavage rate and developmental rate over 3-cell were lower at the concentration of 1.OOrnM than the other treatment concentrations, otherwise the blastocysts rate was higher as 23.2% than the others. That result showed that as like reported group which had higher develop-mental rate over 3-cell was also higher to the blastocysts rate. In case of D-glucose, there was no effects through the concentration changes. It was the result of this study for which the use of BOEC coculture system and 1.OOmM Na-pyruvate as an energy source had an effect upon embryo development.

• Journal of the Korea Computer Graphics Society
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• v.21 no.4
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• pp.1-10
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• 2015

Recently, calligraphy has become popular because people focused on emotion. The strokes, dots, swoops, cracks and shading are the calligraphy factors for expressing various emotions such as joy, anger, sorrow, and delight. However, the emotion which is expressed by cracks and shading can be destroyed in the digital work when the calligraphy is used for a variety sizes of prints. Professionals work with high-resolution images which are obtained through the scanner, however normal users should work with low-resolution images taken with the smart phone for calligraphy image editing. We propose a raster image scaling method focused on calligraphy that maintains the emotion with cracks and shading, when normal users use the low-resolution calligraphy images in the digital work. The method recolors aliasing boundary of enlarged rasterized image. When recolored by our method, our method decreases aliasing by using the image gradient method, vivify calligraphy images, and maintains the emotion in cracks and shading by using the alpha value.

• Journal of the Korean Institute of Gas
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• v.17 no.1
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• pp.26-34
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• 2013

The multiphase flow analysis related to phase change can be adapted to lots of areas such as evaporation and condensation has many interesting branches due to complicated phenomenon. In this study, the experimental investigation of cryogenic liquid in the porous media with various densities was shown how the cryogenic liquid behaves in the porous structure. For this study, permeability behaviors under different applying pressure of the glass wool with different bulk densities are discussed. Experimental investigation on the behavior of cryogenic liquefied nitrogen in the porous media is conducted. The result was that the non linearity of pressure gradient with location is increased and the permeability is decreased as the bulk density of glass wool increased. Lastly, simulation results with CFD commercial package program are used to realize the cryogenic liquid's flow in porous media to compare the finding with experimental results.

• The Korean Journal of Mycology
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• v.37 no.2
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• pp.161-166
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• 2009

The purpose of the present study is to develop a simple, fast and sensitive LC/MS method for simultaneous separation and the determination of an active component in the oriental medicinal mushroom Cordyceps militaris. Based on this work, the contents of cordycepin in Cordyceps militaris fruiting cultivated on various media were determined and compared. And also, the nutritional components such as minerals and vitamins were determined in order to provide useful information to consumer as a food material. The analysis methods of nutritional components were chosen on the basis of AOAC. The optimum separation for cordycepin was achieved using a solvent gradient consisting of the mixture of 0.1% formic acid in methanol (solvent B) in a background of 0.1% formic acid in water (solvent A) as a mobile phase and a 3.0${\times}$150 Waters XTera column. Selective ion monitoring (SIR) mode ([M+H]+ at m/z 252) was used for quantitative analysis of cordycepin. The cultivated Cordyceps militaris on various media contained 1~14 /g of cordycepin, 0.65~1.08% of thiamine, 0.86~7.17% of riboflavin, and 3.01~5.26% of niacin. The content of mineral components varied on categories, especially contained 500~3500% of potassium as a major mineral. Cordycepin, niacin and potassium were found much higher in the fruiting cultivated with soy power media (gold 10) than other media.

• International Journal of Fuzzy Logic and Intelligent Systems
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• v.13 no.3
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• pp.186-199
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• 2013

We pose pattern classification as a density estimation problem where we consider mixtures of generative models under partially labeled data setups. Unlike traditional approaches that estimate density everywhere in data space, we focus on the density along the decision boundary that can yield more discriminative models with superior classification performance. We extend our earlier work on the recursive estimation method for discriminative mixture models to semi-supervised learning setups where some of the data points lack class labels. Our model exploits the mixture structure in the functional gradient framework: it searches for the base mixture component model in a greedy fashion, maximizing the conditional class likelihoods for the labeled data and at the same time minimizing the uncertainty of class label prediction for unlabeled data points. The objective can be effectively imposed as individual mixture component learning on weighted data, hence our mixture learning typically becomes highly efficient for popular base generative models like Gaussians or hidden Markov models. Moreover, apart from the expectation-maximization algorithm, the proposed recursive estimation has several advantages including the lack of need for a pre-determined mixture order and robustness to the choice of initial parameters. We demonstrate the benefits of the proposed approach on a comprehensive set of evaluations consisting of diverse time-series classification problems in semi-supervised scenarios.

• KSBB Journal
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• v.15 no.6
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• pp.605-608
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• 2000

Oligodeoxynucleotides (ODNs) were separated by high-performance membrane chromatography (HPMC), a combined system of chromatography and membrane. The separation mechanism involved anion-exchange, and the stationary phase was cation CIM (Convective Interaction Media) DEAE disk (16${\times}$3 mm). Two types of mobile phase were used, buffer A (20mM Tris-HCl, pH 7.4) and buffer B (buffer A + 1M NaCl). As the amount of NaCl dissolved in buffer linearly increased, the retention time shortened, which enabled a gradient elution mode. Based on the number of theoretical plates and resolution observed, the optimum mobile phase and operating condition (Buffer A/Buffer B=50/50 - 20/80 vol%, gradient time 2 min) were experimentally determined. In this experimental condition, ODNs were separated within 2 min at a mobile phase flow rate of 6 ml/min.

• International Journal of Computer Science & Network Security
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• v.22 no.7
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• pp.352-358
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• 2022

Text mining is an important process used for analyzing the data collected from different sources like videos, audio, social media, and so on. The tools like Natural Language Processing (NLP) are mostly used in real-time applications. In the earlier research, text mining approaches were implemented using long-short memory (LSTM) networks. In this paper, text mining is performed using average-stochastic gradient descent weight-dropped (AWD)-LSTM techniques to obtain better accuracy and performance. The proposed model is effectively demonstrated by considering the internet movie database (IMDB) reviews. To implement the proposed model Python language was used due to easy adaptability and flexibility while dealing with massive data sets/databases. From the results, it is seen that the proposed LSTM plus weight dropped plus embedding model demonstrated an accuracy of 88.36% as compared to the previous models of AWD LSTM as 85.64. This result proved to be far better when compared with the results obtained by just LSTM model (with 85.16%) accuracy. Finally, the loss function proved to decrease from 0.341 to 0.299 using the proposed model

• Journal of the Korea Society for Simulation
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• v.16 no.1
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• pp.21-29
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• 2007

In this paper, we present a method of detecting the boundary of the intima-media complex for automated measurement based on dynamic programming from carotid artery B-mode ultrasound images and then show the experimental results. We apply the dynamic programming for determining the optimal locations that a cost function is minimized. The cost function includes cost terms which are representing image features such as intensity, intensity gradient and geometrical continuity of the vessel interfaces. Moreover, we improve the boundary continuity by applying the B-spline to smooth the rough boundary due to noise such as speckle, dropout and weak edges. The proposed method has obtained more accurate reproducible results than conventional edge-detection by considering multiple image features and ensures efficient automated measurement by solving the problems of the inter- and intra-observer variability and its inefficiency due to manual measurement.