• Journal of the Computational Structural Engineering Institute of Korea
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• v.30 no.6
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• pp.531-539
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• 2017

This paper deals with the development of bonded joints for fibre reinforced plastic (FRP) hull structures using moulding-in concept. Focus is placed on bonded in-plane connections between two adjacent panels that could form the boundaries of hull structural module. Traditional construction in FRP hull structures requires the construction of a mould, usually from steel or aluminium. In this construction the FRP materials are laid in the mould, and resin is saturated, and then the structural member is cured. This is expensive since it involves the fabrication of metal hull mould for every different hull type, which is sacrificed after the production of the FRP ship. One way of encouraging greater use of FRP in ship construction is to investigate the possible construction of FRP hull structures in a similar manner to metallic ships, that is in terms of blocks or modules. Such a manner of construction would eliminate the need for expensive hull moulds permitting greater flexibility in the construction of FRP ships. The main issue then would be the design and construction of adequate bonded connections between adjacent panels. To fulfill this object, the simplified and automated way of manufacturing joint edge shapes for bonded joints is developed, and their structural assessment is performed in both experimentally and numerically.

• Journal of the Korean Society of Costume
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• v.67 no.2
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• pp.101-115
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• 2017

Ancient documents, characters, and relics are the utmost important materials when it comes to researching ancient clothing. Of these, the ancient characters explain the contents of the time, which makes it an objective historical record. China has hieroglyphics, such as oracle bone inscription and bronzeware script, which existed in Sang[Eun] Ju era. This character is formed by a simple line and detailed drawing, showing the object or the concrete form and characteristics, so the reader can understand the meaning. Oracle bone inscription and bronzeware script, which are written in pictograph, include contents that help to grasp the original shape and form of ancient official hats. Chinese characters Geon(巾, 건) Byun(㝸, 변) Myun(免, 면) Mo(冒, 모) Ju(冑, 주) and Kwan(冠, 관), which are the names of the official hats, have been researched, and Mi(美, 미) Ryung(令, 령) Wang(王, 왕) and Hwang(皇, 황), which are the characters related to the official hats, have been studied. Geon(巾, 건) switched its form from shape of material around waist to wraping wearer's head. Byun(㝸, 변) is a hat with decoration, and Myun(免, 면) is in form of a helmet with ornaments. Mo(冒, 모) in bone script looks like a hat with decorations on each sides, but in bronzeware script, it is more like a simple round hat Ju(冑, 주) covers one's head and has decorated ornaments, and The Kwan(冠, 관), which is now a common name of official hats, is not shown in oracle bone inscription or bronzeware script, It might have been used later than the other two types of hats. As for the related Chinese characters, Mi(美, 미) is in the shape of a feather decoration, Ryung(令, 령) is similar in shape to the letter 'A', and Wang(王, 왕) is in shape of simple hat from 령 with decorations. Hwang(皇, 황) is like a Wang(王, 왕) hat, but with fancier decorations. Oracle bone inscription and bronzeware script show the original form and shape of ancient hats.

• Journal of Yeungnam Medical Science
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• v.19 no.2
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• pp.99-106
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• 2002

Background: Simple ventricular septal defect(VSD) is the most common congenital heart disease. Although closure of VSD is currently associated with a relatively low risk, experience with younger and smaller infants has been variably less satisfactory. We assessed the results of surgical closure of VSD in infant. Materials and Methods: Between 1996 and 2000, 45 non-restrictive VSD patients underwent patch repair and retrospective analysis was done. Patients were divided into two groups based on weight: group I infants weighed 5kg or less(n=16), and group II infants weighed more than 5kg(n=29). Both groups had similar variation in sex, VSD location, aortic cross clamp time and total bypass time. But combined diseases (ASD, PDA, MR) were more in group I. We closed VSD with patch and used simple continuous suture method in all patients. Results: There were no operative mortality, no reoperation for hemodynamically significant residual shunt and no surgically induced complete heart block. As a complication, pneumonia(group I: 2 cases, group II: 2 cases), transient seizure(group II: 2), wound infection(group I: 1, group II: 1), urinary tract infection(group I: 1) and chylopericardium(group I: 1) developed, and there was no significant difference between two groups(p>0.05). Conclusion: Early primary closure with simple continuous suture method was applicable in all patients with non-restrictive VSD without any serious complications.

• Investigative Magnetic Resonance Imaging
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• v.7 no.2
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• pp.137-143
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• 2003

Purpose : B1 field of birdcage RF (radiofrequency) coil that is used most for brain imaging in magnetic resonance imaging (MRI) decreases toward endring from the coil center. We investigated how much RE B1 homogeneity effect the endcap shield brings form the coil center as it towards to endcap region. Materials and Methods : We compared RF B1 field distribution by each finite difference time domain (EDTD) simulations for lowpass, highpass and hybrid birdcage RF coils. We selected the highpass birdcage RF coil that was the highest RF B1 field condition as simulation result, and studied how much RF B1 homogeneity effect was occurred when endcap shield was applied to endring area. Results : B1 field of the highpass birdcage RF coil was higher than other birdcage RF coil types as simulation result. However, the RF B1 homogeneity was lower than other coil types. RE B1 field of highpass birdcage RF coil with endcap shield is similar with RF B1 field of hybrid birdcage RF coil and the overall RE B1 homogeneity in sagittal direction was better. Conclusion In this paper, proposed method can apply improving RF B1 homogeneity of RF coil in clinical examination.

• Investigative Magnetic Resonance Imaging
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• v.13 no.1
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• pp.63-73
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• 2009

Purpose : To investigate the effects of various intracranial volume (ICV) measurement methods on the sensitivity of hippocampal volumetry and modulated voxel-based morphometry (mVBM) in female patients with major depressive disorder (MDD). Materials and Methods : T1 magnetic resonance imaging (MRI) data for 41 female subjects (21 MDD patients, 20 normal subjects) were analyzed. Hippocampal volumes were measured manually, and ICV was measured manually and automatically using the FreeSurfer package. Gray and white matter volumes were measured separately. Results : Manual ICV normalization provided the greatest sensitivity in hippocampal volumetry and mVBM, followed by FreeSurfer ICV, GWMV, and GMV. Manual and FreeSurfer ICVs were similar in normal subjects (p = 0.696), but distinct in MDD patients (p = 0.000002). Manual ICV-corrected total gray matter volume (p = 0.0015) and Manual ICV-corrected bilateral hippocampal volumes (right, p = 0.014; left, p = 0.004) were decreased significantly in MDD patients, but the differences of hippocampal volumes corrected by FreeSurfer ICV, GWMV, or GMV were not significant between two groups (p > 0.05). Only manual ICV-corrected mVBM analysis was significant after correction for multiple comparisons. Conclusion : The method of ICV measurement greatly affects the sensitivity of hippocampal volumetry and mVBM. Manual ICV normalization showed the ability to detect differences between women with and without MDD for both methods.

• Investigative Magnetic Resonance Imaging
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• v.13 no.1
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• pp.22-30
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• 2009

Purpose : Patient motion during magnetic resonance (MR) imaging is one of the major problems due to its long scan time. Entropy based post-processing motion correction techniques have been shown to correct motion artifact effectively. One of main limitations of these techniques however is its long processing time. In this study, we propose several methods to reduce this long processing time effectively. Materials and Methods : To reduce the long processing time, we used the separability property of two dimensional Fourier transform (2-D FT). Also, a computationally light metric (sum of all image pixel intensity) was used instead of the entropy criterion. Finally, partial Fourier reconstruction, in particular the projection onto convex set (POCS) method, was combined thereby reducing the size of the data which should be processed and corrected. Results : Time savings of each proposed method are presented with different data size of brain images. In vivo data were processed using the proposed method and showed similar image quality. The total processing time was reduced to 15% in two dimensional images and 30% in the three dimensional images. Conclusion : The proposed methods can be useful in reducing image motion artifacts when only post-processing motion correction algorithms are available. The proposed methods can also be combined with parallel imaging technique to further reduce the processing times.

• Journal of Mushroom
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• v.7 no.3
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• pp.91-97
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• 2009

This expriment was carried out on culture media which affect growth, development and physiological effect to Pleurotus ostreatus, when aqueous ferrum, red pepper powder, leaves of ginkgo biloba were added to culture media. The yield of fresh mushroom per 850ml PP bottle in chunchu-neutari was highest by 144g in 34.9g aqueous ferrum added, ferrous content don't affected to yield of mushroom, but variety of Pleurotus ostreatus affect to yield. Mineral content of fruit body and culture media in Suhan-neutari was different to mineral kind, ferrous content of furit body was similar to 0.31~0.43mg/kg when ferrous content of media was increased in 0.89mg/kg to 10.8mg/kg. The more content of red pepper powder in culture media was high, the more capsaicin content in fruit body was high. transferred capsaicin was highest by 6 mg/100g in Suhan-neutari. Total phenolics content were higher in culture media which was added aqueous ferrum and red pepper powder, but correlation don't showed total phenolics content among antioxydant activity, reducing power, chelating capacity. Macrophage activation was higher in Suhan-neutari than other Pleurotus spp.

• Journal of the Korea Society of Computer and Information
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• v.16 no.11
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• pp.85-93
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• 2011

The music education improves the creative talent, social skills and academic achievement of the students. For the efficient music education, the learner centered study is highly recommended rather than the passive education, which supports self-control in selecting teaching materials, learning patterns and speed. For the successful self learning, it is requested to develop the collaborative educational learning tools, especially electronic collaborators such as H/W and S/W. Though there exist many commercialized electronic instruments and the PC MIDI based softwares, these tools have some limits and problems for the primary student to learn playing the musical instrument by himself. In this paper, we propose a supporting tool implementation method using an electronic keyboard instrument with USB Interface and PC-based software to help the primary student to learn playing the musical instrument. We implemented an electronic keyboard instrument module compactly and at low cost using a PIC18F4550 MCU. PC based software was developed to edit musical score, process the MIDI information, and interact with the electronic keyboard instrument module. This tool can offer a similar keyboard instrument environment and can be incorporated with self learning contents.

• Journal of architectural history
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• v.3 no.1
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• pp.57-82
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• 1994

This paper is the result of the researches and the field surveys of the villages and the dwellings of Korean immigrants in Yien-Pien area, north-eastern China. This study aims to persue both of the origin and the process of development of their settlements and dwelling types from late 19C to the present. Their processes are too complex to analysis by single view-point. I have eyes to interprete them from three pionts; 1)correspondences between the dwelling types and the econo-political history of their region, 2)cultural assimilation with the native dwelling types, and 3)the direction of their modernization with the economical development of modern China. Three village types have been pioneered; 1)the villages of indivisual immigration, 2)the villages of planned group immigration, and 3)the villages of socilistic reform villages of 1) were composed of organic village patterns and various shaped dwelling lots on the sloped site; villages both of 2) and 3), gird patterns and uniformed lots on open fields. Historically, villages of 1) were pioneered before 1931; villages of 2), 1936-1945; villages of 3), from 1945. Each of dwelling types had strong relations with the village types to which it belonged. Before 1931, dwellings were built up based on so called "Ham-buk dwelling type" which was dominent in north-eastern Korea. In the era of gruop-immigration, various dwelling types were flew into Yen-Pien from southern Korea. In modern China, their southern types were changed into Yen-Pien type as similar as Ham-book type. After 1945, with the Great leap Forward and the Cultural Revolution, as communization of indivisual properties and reorganization of rural communities, each of dwellings became smaller and simpler in aspects of scales as well as functions. There are two types in Yen-Pien dwellings, those are 'single-file' and 'double-file' type. Three sub-types of latter arc 'six-bays', 'eight-bays', and rarely 'ten-bays'. The most common element of all types is Chong-ju-k'an; which is large room with heated floor, openig to kitchen. Now, modern dwellings of Korean immigrants are changing their spatial compositions, materials, and structures. With cultural assimilation as well as modernization, especially in urban areas, they are compelled to accept the elements of Chinese dwellings. But the spatial element of "Chong-ju-k'an", which is the core element of Yen-Pien dwelling type, never fade away nor is changed.

• Journal of Korean Dental Science
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• v.4 no.2
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• pp.46-51
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• 2011

Purpose: For aesthetic reasons, composite resin brackets are widely used. However, related studies are rare. This pilot study sought to compare the stress distributions in two commercially available composite resin brackets with metal slot. Materials and Methods: Two commercially available resin brackets -- full-metal slot resin bracket (fSRB) and partial-metal slot resin bracket (pSRB) with straight wire appliance dimension of $0.022{\times}0.028$ in -- were selected. In each bracket, 3-dimensional finite element models were constructed, and stress level was evaluated using finite element analysis. By loading the tipping force and torsion moment, which are similar to those applied by the stainless steel rectangular wire ($0.019{\times}0.025$ -in), stress distributions were calculated, and von Mises stress values were obtained. Results: In pSRB and fSRB, the stress value of the torque moment was much higher than that of the tipping force. The pSRB showed higher stress value than fSRB in both tipping force and torque moment because of the difference in size and configuration of the metal frame inserted into the slot. More stress was also found to be concentrated on the slot area than the wing area in fSRB. Conclusion: The slot form of fSRB was found to be more resistant to the stress of tipping and torque than the slot form of pSRB. In addition, the slot areas -- rather than the wing areas -- of the bracket showed breakage susceptibility. Therefore, resistance to the torque moment on the slot area should be considered in bracket design.