• Advances in nano research
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• v.9 no.3
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• pp.211-220
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• 2020

This paper investigates the effect of linear and non-linear distribution of carbon nanotube volume fraction in the FG-CNTRC beams on the critical buckling by using higher-order shear deformation theories. Here, the material properties of the CNTRC beams are assumed to be graded in the thickness direction according to a new exponential power law distribution in terms of the carbon nanotube volume fractions. The single-walled carbon nanotube is aligned and distributed in the polymeric matrix with different patterns of reinforcement; the material properties of the CNTRC beams are described by using the rule of mixture. The governing equations are derived through using Hamilton's principle. The Navier solution method is used under the specified boundary conditions for simply supported CNTRC beams. The mathematical models provided in this work are numerically validated by comparison with some available results. New results of critical buckling with the non-linear distribution of CNT volume fraction in different patterns are presented and discussed in detail, and compared with the linear distribution. Several aspects of beam types, CNT volume fraction, exponent degree (n), aspect ratio, etc., are taken into this investigation. It is revealed that the influences of non-linearity distribution in the beam play an important role to improve the mechanical properties, especially in buckling behavior. The results show that the X-Beam configuration is the strongest among all different types of CNTRC beams in supporting the buckling loads.

• Journal of Oriental Medical Thermology
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• v.2 no.1
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• pp.1-5
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• 2003

Dysmenorrhea is one of the common gynecologic disorders of menstruation women. Primary dysmenorrhea is menstrual pain without pelvic pathology. whereas secondary one is painful mestruation with underlying pathology. The cause of primary dysmenorrhea is increased endometrial prostaglandin. The mechanisims underlying secondary dysmenorrhea are not eluciated. There are many blood vessels under the skin and they play a very important role in the thermal control of peripheral part. The control of blood circulation is mainly controlled by autonomic nervous system and it is known that D.I.T.I. (digital infra-red thermographic imaging) is an objective method showing the body temperature. I observed the abdominal themerature of 49 patients complaning of dysmenorrhea who visited the gynecologic department of Pundang Oriental Medical Hospital during 1997. In order to rule out thermal abnormality due to obesity. the causes whose obesity index were above I. were excluded in this study. The mean temperature of lower abdomen of the dysmenorrhea group was $35.22{\pm}1.33^{\circ}C$ and control group was $36.01{\pm}0.74^{\circ}C$.

• Journal of Information Processing Systems
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• v.13 no.2
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• pp.400-416
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• 2017

Music emotion is an important component in the field of music information retrieval and computational musicology. This paper proposes an approach for automatic emotion classification, based on rough set (RS) theory. In the proposed approach, four different sets of music features are extracted, representing dynamics, rhythm, spectral, and harmony. From the features, five different statistical parameters are considered as attributes, including up to the $4^{th}$ order central moments of each feature, and covariance components of mutual ones. The large number of attributes is controlled by RS-based approach, in which superfluous features are removed, to obtain indispensable ones. In addition, RS-based approach makes it possible to visualize which attributes play a significant role in the generated rules, and also determine the strength of each rule for classification. The experiments have been performed to find out which audio features and which of the different statistical parameters derived from them are important for emotion classification. Also, the resulting indispensable attributes and the usefulness of covariance components have been discussed. The overall classification accuracy with all statistical parameters has recorded comparatively better than currently existing methods on a pair of datasets.

• Transactions of the Korean Society of Automotive Engineers
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• v.11 no.5
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• pp.89-94
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• 2003

Rolling stock structures such as bogie frame and car body play an important role for the support of vehicle leading. In general, more than 25 years' durability is needed for them. A lot of study has been carried out for the prediction of the fatigue life of the bogie frame and car body in experimental and theoretical domains. One of the new methods is a probabilistic fatigue lift evaluation. The objective of this paper is to estimate the fatigue lift of the bogie frame of an electric car, which was developed by the Korea Railroad Research Institute (KRRI). We used two approaches. In the first approach probabilistic distribution of S-N curve and limit state function of the equivalent stress of the measured stress spectra are used. In the second approach, limit state function is also used. And load spectra measured by strain gauges are approximated by the two-parameter Weibull distribution. Other probabilistic variables are represented by log-normal and normal distributions. Finally, reliability index and structural integrity of the bogie frame are estimated.

• Structural Engineering and Mechanics
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• v.64 no.5
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• pp.527-541
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• 2017

In this work, a new hyperbolic shear deformation beam theory is proposed based on a modified couple stress theory (MCST) to investigate the bending and free vibration responses of functionally graded (FG) micro beam made of porous material. This non-classical micro-beam model introduces the material length scale coefficient which can capture the size influence. The non-classical beam model reduces to the classical beam model when the material length scale coefficient is set to zero. The mechanical material properties of the FG micro-beam are assumed to vary in the thickness direction and are estimated through the classical rule of mixture which is modified to approximate the porous material properties with even and uneven distributions of porosities phases. Effects of several important parameters such as power-law exponents, porosity distributions, porosity volume fractions, the material length scale parameter and slenderness ratios on bending and dynamic responses of FG micro-beams are investigated and discussed in detail. It is concluded that these effects play significant role in the mechanical behavior of porous FG micro-beams.

• Fashion & Textile Research Journal
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• v.18 no.2
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• pp.139-148
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• 2016

There is an expanding global network of free trade agreements (FTA). High-quality, comprehensive free trade agreements play an important role to support global trade liberalization and are explicitly allowed under the World Trade Organization (WTO) rules. An FTA is an international treaty that removes barriers to trade and facilitates stronger trade and commercial ties that contribute to increased economic integration between participating countries. Korea benefits from the global FTA trend; however it has started and developed FTA negotiations later than other countries. Current FTA agreements exist with Chile, Singapore, EFTA, ASIAN, India, EU, Peru, USA, Turkey, Australia, and Canada; in addition, there are ongoing negotiations with China, Colombia, New Zealand, and Vietnam. FTA open up opportunities for the textile/clothing industry to expand businesses into key overseas markets. FTA improve market access across all areas of trade to help maintain and stimulate the competitiveness of textile/clothing firms. This study examines the expansion of free trade agreements in light of changes in the international trade environment and the status of the Korean textile/clothing industry. Korea's textile/clothing export/import products and concession of tariff, country of origin covered under Korea-US/China FTA are investigated to identify problems. This study provides practical and policy implications for the textile/clothing industry in regards to the Korea-US/China FTA.

• Korean Journal of Materials Research
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• v.19 no.5
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• pp.270-275
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• 2009

Lotus-type porous nickel with cylindrical pores was fabricated by unidirectional solidification under an Ar gas atmosphere using the thermal decomposition method of the compounds such as sodium hydroxide, calcium hydroxide, calcium carbonate, and titanium hydride. The decomposed gas does form the pores in liquid nickel, and then, the pores become the cylindrical pores during unidirectional solidification. The decomposed particles from the compounds do play a rule on nucleation sites of the pores. The behavior of pore growth was controlled by atmosphere pressure, which can be explained by Boyle's law. The porosity and pore size decreased with increasing Ar gas pressure when the pores contain hydrogen gas decomposed from calcium and sodium hydroxide and titanium hydride, ; however it they did not change when the pores contain containing carbon dioxide decomposed from calcium carbonate. These results indicate that nickel does not have the solubility of carbon dioxide. Lotus-type porous metals can be easily fabricated by the thermal decomposition method, which is superior to the conventional fabrication method used to pressurized gas atmospheres.

• Journal of Korea Game Society
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• v.16 no.1
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• pp.23-32
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• 2016

A recent emotion research has attracted attention as an element to enhance the interaction with the user to play the game. Emotion expressed in the previous game was using a simple structure. However, increasing the user's needs of emotions that have been used in the game is necessary to structure the emotions caused. In this paper, it was utilized for the character of emotion in the game rules of the proposed emotion based on the principle of biological feelings. And it was classified a game component that affects the emotions and character provides a structure for recognizing the emotion from the game. This paper provides a structural framework to be considered in order to analyze emotions used in existing game to the role of emotion, to express emotion in the game.

• Culinary science and hospitality research
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• v.10 no.1
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• pp.96-115
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• 2004

Though the foodservice industry in Korea has developed in the aspect of quantity, it has left behind in the aspect of quality compared with other foreign countries. Previous researches has just indicated that the menu should be built through mutual consent between a menu planner and a menu-book designer without defining the concept of menu. Therefore, it is necessary to establish a theoretical basis about the menu-book, showing quality of the foodservice industry in Korea. First of all, a menu planner's understanding to the menu-book should be changed and also a menu designer should understand positively the foodservice industry. Therefore the utility of menu-book can be maximized as a communication and marketing method breaking from simplicity and aesthetic. Both food items and design have a common feature to explain emotion, history and culture of a people. Menu planner and menu-book designer should undertake a role of solving one of the most important human desire by distinction and creativity. And they should play a role as a cultural creator through designing the menu-book which can spread out traditional food culture to the world.

• Biodesign
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• v.6 no.4
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• pp.100-102
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• 2018

Autophagy is a degradation pathway that targets many cellular components and plays a particularly important role in protein degradation and recycling. This process is very complex and several proteins participate in this process. One of them, P62/SQSTM1, is related to the N-end rule and induces protein degradation through autophagy. The P62/SQSTM1 makes a huge oligomer, and this oligomerization is known to play an important role in its mechanism. This oligomerization takes two steps. First, the PB1 domain of P62/SQSTM1 makes the base oligomer, and then, when the ligand binds to the ZZ domain of P62/SQSTM1, it induces a higher oligomer by the disulfide bond of the two cysteines. To understand the oligomerization mechanism of P62/SQSTM1, we need to know the dimerization of the PB1 domain. In this study, crystals of PB1 dimer were made and the crystals were diffracted by X-ray to collect usable data up to 3.2A. We are analyzing the structure using the molecular replacement (MR) method.