• Nuclear Engineering and Technology
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• v.52 no.2
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• pp.337-343
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• 2020

Oxide dispersed strengthened (ODS) steel is an important candidate for Gen-IV reactors. Oxide embedded in Fe can help to trap irradiation defects and enhances the strength of steel. It was observed in this study that the size of oxide has a profound impact on the depinning mechanism. For smaller sizes, the oxide acts as a void; thus, letting the dislocation bypass without any shear. On the other hand, oxides larger than 2 nm generate new dislocation segments around themselves. The depinning is similar to that of Orowan mechanism and the strengthening effect is likely to be greater for larger oxides. It was found that higher shear deformation rates produce more fine-tuned stress-strain curve. Both molecular dynamics (MD) simulations and BKS (Bacon-Knocks-Scattergood) model display similar characteristics whereby establishing an inverse relation between the depinning stress and the obstacle distance. It was found that (110)_oxide || (111)_Fe (oriented oxide) also had similar characteristics as that of (100)_oxide || (111)_Fe but resulted in an increased depinning stress thereby providing greater resistance to dislocation bypass. Our simulation results concluded that critical depinning stress depends significantly on the size and orientation of the oxide.

• Human Ecology Research
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• v.52 no.2
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• pp.103-110
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• 2014

The purpose of this study was to seek improvement in clothing education through an application of creative crochet activities for children. A total of 111 students of 4th grade classes from elementary school participated in this program during 16 classes of creative activities from April to May 2013. The content of the creative crochet activities was organized into orientation (making rings etc.), making work I (counting stitches, rows, etc.), making work II (set up a pillar by chains etc.), and completing and sharing the work (making a string by chain and single crochet stitches etc.). Before and after the classes, children's creative personality and their attitudes toward clothing were investigated. The study also analyzed the mean, standard deviation, and paired-sample t-test for comparison between the pre- and post-test results. According to the results, first, the creative crochet activities were analyzed to be helpful and useful in developing a child's creative personality, which includes elements such as sensitivity and curiosity. Further, these activities were more effective in the case of girls than in the case of boys with respect to fostering a creative personality. Second, the creative crochet activities were analyzed as being helpful and useful in developing attitudes toward clothing, which include elements such as clothing satisfaction, clothing management, and clothing independence. Further, these activities were more effective in the case of boys than in the case of girls with respect to fostering attitudes toward clothing. Third, clothing education is an appropriate topic for creative activities of Korean elementary schools.

• Journal of the Korean Society of Costume
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• v.59 no.4
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• pp.98-110
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• 2009

Performance art is an integrated genre of different art areas, and make-up is a visual art area to give lively effects to the performance art, which makes actors and actresses changed into the characters of plays. It can be said to be a kind of deliverer of idea to help effectively understand the contents of the performance. When we are in the world abundant in various cultures and innumerable styles of expression of different countries, we should rediscover the value of the beauty of our traditional masks that have represented the emotion and thought of Han nation, which we can find in play culture of our ancestors that has kept our ancestors' value system. That's the way we can get continuous life force and competitive power of our traditional culture. The Korean traditional masks haven't only been for the prevention of bad luck and the prayer of fortune, but also well expressed Korean people's looks, features and personalities according to the roles. They are excellent artistic works in themselves, and many studies have been performed on the analyses and uses of the features of the masks in various fields due to their good expression of different cultural aspects, while the studies in the light of make-up are rarely performed. Therefore, this article aims to analyze the features of the Korean traditional masks and, by using this analysis, to present effective make-up designs in outdoor performances through a stage performance. In addition, this article also tries to present the orientation of make-up as an expression of artistic image, and to expand the expression area of make-up by using the Korean traditional masks in the light of make-up. For this purpose, I examined the related literature and the precedent study materials to find the origin and kinds of the Korean traditional masks, and analyzed the features of the masks. Furthermore, I established the make-up design plan using the material features of the Korean traditional masks by analyzing the characters in actual performance works, and presented the photos of works actually performed.

• The Academic Congress of Korean Shoulder and Elbow Society
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• 1995.05a
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• pp.22-22
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• 1995

One hundred and forty-eight cases of tennis elbow were treated by conservative managements firstly such as rest, medication, immobilization, physical therapy and local steroid injection, from Jan. 1985 to Jun. 1994 at Department of Orthopaedic Surgery, National Medical Center. Among the 148 cases, 16 cases who failed conservative managements, were treated with Nirschl & Pettrone operation. The results were summarized as follows, 1. Among the 148 cases, 110 cases$(74\%)$ were female, and 61 cases$(41.2\%)$ were in the age group 41 to 50, and mean age was 42.3 2. Ninety-nine cases were housewives and only 15 cases were related to sports. 3. The results 116cases$(78\%)$, of conservative treatment were excellent and good 10 fair and failure in 32 cases$(22\%)$, by Nirschl and Peettrone assessment. 4. Among the 16 cases who were treated with Nirschl and Pettrone operation, excellent result was obtained 10 7cases, good in 3 cases, fair in 4cases and failure in 2 cases. 5. Recurrence was developed in 18 cases$(12.2\%)$, and we obtained excellent & good result in 17 cases with both conservative and operative treatment. Above results suggest that the term, tennis elbow is a misnomer because it occurs more commonly in non-athletes such as housewives than in tennis players. So it seems to be a occupational disease rather than sports injury. Now, we propose eliminate of the term, elbow and substitute with terminology that described the true understanding and therapeutic orientation of it.

• Journal of the Korean Society for Nondestructive Testing
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• v.19 no.2
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• pp.110-117
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• 1999

In order to ultrasonically evaluate creep cavities pure copper samples were subjected to creep test and their microstructures were examined. Ultrasonic velocities. frequency-dependent magnitude spectra and attenuations were measured on a series of copper samples obtained from the different stages of creep test. Velocities measured in three directions with respect to the loading axis decreased and their anisotropy increased as a function of the creep-induced porosity. The anisotropic behavior could be attributed to the progressive change of pore shape and preferred orientation as the creep advanced. The 2% porosity by volume decreased the longitudinal and shear wave velocities by 11% and 4%, respectively. Furthermore, both velocities decreased nonlinearly with the porosity. As the creep damage developed, the magnitude spectra lost high frequency components and their central frequencies shifted to lower values. The attenuation showed almost linear behavior in the frequency range used. Normalized velocity, central frequency shift and attenuation slope were selected as nondestructive evaluation parameters. These results were presented and showed good relations with the porosity content.

• Macromolecular Research
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• v.17 no.2
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• pp.110-115
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• 2009

The electrical, morphological and rheological properties of melt and dry mixed composites of poly ethylene (PE)/graphite (Gr), polypropylene (PP)/Gr and PP/nickel-coated carbon fiber (NCCF) were investigated as a function of filler type, filler content and processing temperature. The electrical conductivities of dry mixed PP/NCCF composites were increased with decreasing processing temperature. For the melt mixed PP/NCCF composites, the electrical conductivities were higher than those of the melt mixed PE/Gr and PP/Gr composites, which was attributed to the effect of the higher NCCF aspect ratio in allowing the composites to form a more conductive network in the polymer matrix than the graphite does. From the results of morphological studies, the fillers in the dry mixed PP/NCCF composites were more randomly dispersed compared to those in the melt mixed PP/NCCF composites. The increased electrical conductivities of the dry mixed composites were attributed to the more random dispersion of NCCF compared to that of the melt mixed PP/NCCF composites. The complex viscosities of the PP/Gr composites were higher than those of the PP/NCCF composites, which was attributed to the larger diameter of the graphite particles than that of the NCCF. Furthermore, the fiber orientation in the 'along the flow' direction during melt mixing was attributed to the decreased complex viscosities of the melt mixed PP/NCCF composites compared those of the melt mixed PP/Gr composites.

• Journal of Magnetics
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• v.21 no.1
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• pp.35-39
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• 2016

$Cr_{100-x}Ti_x$ amorphous texture-inducing layers (TIL) were investigated to realize highly (002) oriented $L1_0$ FePt-C granular films through hetero-epitaxial growth on the (002) textured bcc-$Cr_{80}Mn_{20}$ seed layer (bcc-SL). As-deposited TILs showed the amorphous phase in Ti content of $30{\leq}x(at%){\leq}75$. Particularly, films with $40{\leq}x{\leq}60$ kept the amorphous phase against the heat treatment over $600^{\circ}C$. It was found that preference of the crystallographic texture for bcc-SLs is directly affected by the structural phase of TILs. (002) crystallographic texture was realized in bcc-SLs deposited on the amorphous TILs ($40{\leq}x{\leq}70$), whereas (110) texture was formed in bcc-SLs overlying on crystalline TILs (x < 30 and x > 70). Correlation between the angular distribution of (002) crystal orientation of bcc-SL evaluated by full width at half maximum of (002) diffraction (FWHM) and a grain diameter of bcc-SL indicated that while the development of the lateral growth for bcc-SL grain reduces FWHM, crystallization of amorphous TILs hinders FWHM. $L1_0$ FePt-C granular films were fabricated under the substrate heating process over $600^{\circ}C$ with having different FWHM of bcc-SL. Hysteresis loops showed that squareness ($M_r/M_s$) of the films increased from 0.87 to 0.95 when FWHM of bcc-SL decreased from $13.7^{\circ}$ to $3.8^{\circ}$. It is suggested that the reduction of (002) FWHM affects to the overlying MgO film as well as FePt-C granular film by means of the hetero-epitaxial growth.

• Journal of the Korean Geotechnical Society
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• v.21 no.5
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• pp.103-110
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• 2005

In this paper, the characteristics of excessive horizontal stress components in Korea were studied using more than five hundred measured data set of in-situ hydraulic fracturing test. Based on the in-situ testing data, the magnitude and orientation of the horizontal stress component and variation of stress ratio (K) with depth were investigated. And also horizontal stress magnitude versus depth relationships and distribution limits of stress ratio components were suggested. For the depth less than 310 m in the entire territory, the stress ratio has a tendency to diminish and stabilize with depth, but fur some areas, it was revealed that the excessive horizontal stress fields with stress ratio close to 3.0 below 200 m in depth have formed. The results from the investigation of excessive horizontal stress regions showed that there existed several regions where the localized excessive horizontal stress was big enough to potentially induce brittle failure around the openings at less than 300 m in depth.

• Korean Journal of Crystallography
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• v.8 no.2
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• pp.105-110
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• 1997

1μm-CdS films for a window layer of CdS/CuInSe2 solar cell have been prepared by vacuum of 1x10-3 mTorr. Source and substrate temperature ranges were used 800-1100'C and 50-200℃ respectively. Structural, electircal and optical properties of CdS films have been investigated by X-ray diffractometer (XRD), scanning electron microscopy (SSEM), electrical resistivity, the Hall measurement and optical transmission spectra. Electrical resistivity and optical transmission of the CdS films decreased with the increase in CdS source temperature without substrate heating. All the films had hexagonal structure and strong texture with (002) orientation of grain normal to the substrate glass. CdS films evaporated at 1000℃ were the highest electrical conductivity of 0.9(S/cm). Electrical resistivity and optical transmission at the substrate temperature of 100℃ were 40(Ω,cm) and 80% respectively.

• Journal of the Korean institute of surface engineering
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• v.36 no.1
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• pp.14-21
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• 2003

Thin films of ZrO$_2$ and TiO$_2$ were deposited on Si(100) substrates using RF magnetron sputtering technique. To study an influence of the sputtering parameters, systematic experiments were carried out in this work. XRD data show that the $ZrO_2$ films were mainly grown in the [111] orientation at the annealing temperature between 800 and $1000^{\circ}C$ while the crystal growth direction was changed to be [012] at above $1000^{\circ}C$. FT-IR spectra show that the oxygen stretching peaks become strong due to $SiO_2$ layer formation between film layers and silicon surface after annealing, and proved that a diffusion caused by either oxygen atoms of $ZrO_2$ layers or air into the interface during annealing. Different crystal growth directions were observed with the various deposition parameters such as annealing temperature, RF power magnitude, and added $O_2$ amounts. The growth rate of $TiO_2$ thin films was increased with RF power magnitude up to 150 watt, and was then decreased due to a sputtering effect. The maximum growth rate observed at 150 watt was 1500 nm/hr. Highly oriented, crack-free, stoichiometric polycrystalline $TiO_2$<110> thin film with Rutile phase was obtained after annealing at $1000^{\circ}C$ for 1 hour.