• Journal of the Korea Academia-Industrial cooperation Society
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• v.13 no.10
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• pp.4398-4404
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• 2012

This thesis was conducted a numerical analysis on the radiant heat performance according to factors of design of heat sink for cooling of the automotive LED head lamp. The heat sinks were designed with 5 different types to fit the limited internal space by formula based on an existing product (Type 1). Designed heat sinks of five types were analyzed by ANSYS CFD V12.1, and the analysis results were compared with the existing type. The results of simulation were analyzed temperature distribution and average temperature, air flow characteristic, heat flux etc. This thesis was researched on the correlation of the cooling performance according to the heat sink structure and the fin shape. Through numerical analysis, could be confirmed heat sink Type 2 as the best results.

• Journal of the Ergonomics Society of Korea
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• v.30 no.2
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• pp.339-347
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• 2011

Objective: The purpose of this study was to evaluate of various material of pillows by using biomechanical variables such as the cervical stability, head pressure distribution, and muscle activity. Method: Eight subjects participated in the experiment. Three different materials such as polyester sponge, memory foam and the buckwheat shell used for Korean traditional pillow were tested. Electro-goniometer, six channels of electromyography(EMG), ten channels of the head pressure sensors were used to measure the biomechanical responses. Surface electrodes were attached to the right/left semispinals capitis(RSC, LSC), the right/left sternocleidomastoid(RSM, LSM), the right/left upper trapezius(RUT, LUT). The cervical stability was evaluated by the angle deviated from the standing neck position. The head pressure distribution was evaluated by the pressure per unit area recorded on the sensors and the intensity of peak pressure. Electromyography(EMG) data were analyzed by using root mean square(RMS) and mean power frequency(MPF). Results: The buckwheat shell material showed a higher stability in the cervical spine then the other pillows during spine position. In terms of head pressure distribution, the memory form indicated the lowest pressure at supine position, buckwheat shell material indicated the lowest pressure during lying down to side, and polyester cushion recorded the highest pressure at all postures. Conclusion: The buckwheat shell material has a biomechanical advantage to maintain a healthy neck angle and reduce the pressure on the head, which means the buckwheat shell is a potential material for ergonomic pillow design. The pillow with memory form showed second best biomechanical performance in this study. Application: The shape of the buckwheat shell pillow and the characteristics of materials can be used to design the pillow preventing neck pain and cervical disk problems.

• Journal of IKEEE
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• v.12 no.4
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• pp.185-195
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• 2008

In this paper, PIFA(Planar Inverted F Antenna) which operates in PCS(Personal Communication System) band is designed and characteristics are investigated. Designed PIFA was installed in three types of handsets, folder, bar, slide, and the performance was evaluated. Head and hand phantom were added to make the most similar environment to real condition of mobile phone use, and influences on antenna performance were analyzed. The simulation results confirm radiation patterns are greatly changed and antenna efficiency is decreased by the effect of human body. Performance variation of the mobile handset antenna was observed as changing the angle between mobile handset and head phantom from $0^{\circ}$ to $2^{\circ},\;4^{\circ}$ to confirm the variation caused by the relative position of mobile handset and head phantom. Directivity was decreased gradually as the antenna goes away from head phantom, and showed the trend of increasing efficiency. But in the case of bar type, where the position of antenna is relatively close to head phantom, that trend didn't show. It was confirmed that the shape of handset has a great effect on the performance.

• Korean Journal of Head & Neck Oncology
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• v.13 no.1
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• pp.30-34
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• 1997

Objectives: Calcification of the thyroid nodule has been reported to have a close relationship with differentiated thyroid carcinoma, however there are limited studies on the relationship between the calcified thyroid nodule and thyroid malignancy. The authors studied the clinical significance of calcification within the thyroid nodule. Materials and Methods: There were total of 60 patients who underwent surgery for calcified thyroid nodules which were identified from plain neck X-ray, ultrasound and computed tomography during the period January 1991 to June 1996 at the Department of Otorhinolaryngology-Head and Neck Surgery of Korea University Hospital. Six patients were not included because of recurrence and previous thyroid surgery. Histopathologic and radiologic analysis was done on the remaining 54 patients. Results: Results showed that 25 of 54 cases(46%) to be malignant histopathologically. Of the 25 malignant cases, papillary carcinoma was the most common with 22 cases followed by 2 cases of undifferentiated carcinoma and I case of medullary carcinoma. Statistically high incidence of malignancy was observed when the consistency of calcified thyroid nodule was solid, shape of calcification was irregular and inhomogenous, and adhesion of calcified thyroid nodule to the regional structure was present. Conclusion: The probability that a thyroid nodule is malignant has been reported to be 3­20%. However, about half of the thyroid nodules with calcification found to be malignant on this study, calcification of the thyroid nodule can be used as a guideline for detecting thyroid malignancy.

• Journal of Clinical Otolaryngology Head and Neck Surgery
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• v.29 no.2
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• pp.235-239
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• 2018

Due to the structure with one end closed, the external ear resonance effect in which the high frequency is amplified can be generated, and the sound can be perceived well. The external ear resonance normally has a first peak and a second peak. On average, the first peak has a gain of 18.6 dB at 2620 Hz and the second peak has a gain of 18.2 dB at 4210 Hz. The resonance of the external auditory canal changes with the state of the tympanic membrane, the presence of the ventilation tube, and the structure (length, diameter, shape) of the external auditory canal. A patient with a postauricular meatomastoid cutaneous fistula was admitted to the hospital with a foreign body which is the molding of the hearing aid. After removal of the foreign body, the resonance of the external auditory canal was lost and the subjective sound cognitive ability decreased. In the case of postauricular meatomastoid cutaneous fistula, we confirmed the improvement of sound cognitive ability, the change of pure tone hearing threshold, and the change of the external ear resonance after reconstruction of the ear canal without middle ear reconstruction.

• Journal of the Korea Concrete Institute
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• v.19 no.4
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• pp.411-420
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• 2007

The applicability of headed bars in exterior beam-column joints under reversed cyclic loading was investigated. A total of ten pullout tests were first performed to examine pullout behavior of headed bars subjected to monotonic and cyclic loading with test variables such as connection type between head and bar stem (weld or no weld), loading methods (monotonic or cyclic loading), and head shape (small or large circular head and square head). Two full-scale beam-column joint tests were then performed to compare the structural behavior of exterior beam-column joints constructed using two different reinforcement details: i.e. $90^{\circ}$ standard hooks and headed bars. Both joints were designed following the recommendations of ACI-ASCE Committee 352 for Type 2 performance: i.e. the connection is required to dissipate energy through reversals of deformation into inelastic range. The pullout test results revealed that welded head to the stem did not necessarily result in increased pullout strength when compared to non-welded head. Relatively large circular head resulted in higher peak load than smaller circular and square head. Both beam-column joints with conventional $90^{\circ}$ hooks and headed bars behaved similarly in terms of crack development, hysteresis curves, and peak strengths. The joint using the headed bars showed better overall structural performance in terms of ductility, deformation capacity, and energy dissipation. These experimental results demonstrate that the headed bars using relatively small head can be properly designed far use in external beam-column joint.

• Journal of the Korean Society of Clothing and Textiles
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• v.42 no.1
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• pp.74-87
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• 2018

This thesis investigated majo and maja costumes of depicted in Francisco de Goya's paintings from the middle of 18th to the early 19th century, and presented the costumes defined as the upward flow from the lower classes to the upper classes. The study methodology selected those describing the maja and majo among the figure paintings, portraits and genre paintings by Goya that identify unique characteristics with the qualitative analysis of the cases of the upward flow with that affect the costume of the upper classes. The influence of the majo and maja costumes were outstanding in the shape of the outfits while the French style gown of the upper class women were one-piece dresses in shape, those of the maja were two-piece dresses that consisted of the upper and gather skirts. The costume was perfected by use of the mantilla or head kerchief, instead of the headdresses prevalent at those times. The majo's costume affected the men's costume of the upper classes in the shape of the outfits. Short coat and tight breeches were preferred to the loose ones as well as instead of a long coat. Rather than the wigs or tri-corn hat, the head kerchief and sash belt applied, which could be evidence of the upward flow as well as shows proof of the influence of majo and maja costumes.

• Korean Journal of Plant Resources
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• v.13 no.3
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• pp.213-218
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• 2000

Morphological characteristics of 16 collected safflower (Carthamus tinctorius L.)accessions were studied at Gyongbuk A.T.A. Uisong Medicinal Plant Experiment Station in 1998. As for plant height, 5 lines were tall(more than 131cm), which were mainly foreign safflower. Middle and small were 5 and 6 accessions, respectively. Number of branch per plant was 11∼13 in 2 accessions of domestic safflowers while foreign safflowers have more than 50 branches per plant. Leaf shapes were oblong(3 lines), lanceolate(10 lines) and broadly linear(3 lines). There were three types of leaf margin shape which were repand(7 lines), serrate(4 lines) and parted serrate(5 lines). Flower color was white(1 line), yellow(13 lines) and red orange(2 lines). As for flower head shape, 14 lines were conical and 2 lines were flattened. There were thorns on bract of flower head in 11 lines but in 5 lines there were not. Domestic safflower lines had seeds of conical shape. Contrastively, seed shapes of foreign saffower lines were oval.

• The Journal of the Acoustical Society of Korea
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• v.24 no.2
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• pp.68-77
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• 2005

The purpose of a spatial audio system is to give a listener an impression as if he were present in a recorded environment when its sound is reproduced. For this purpose a dummy head microphone is generally used. Because of its human-like shape, dummy head microphone can reproduce spatial images through headphone reproduction. However, its shape and size are restriction to public use and it is difficult to convert the output signal of dummy head microphone into a multi-channel signal for multi-channel environment. So, in this paper, we propose a multi-channel 3D microphone technology. The multi-channel 3D microphone acquire a spatial audio using five microphones around a horizontal plane of a rigid sphere and through post processing, it can reproduce various reproduction signals for headphone, stereo, stereo dipole, 4ch and 5ch reproduction environments. Because of complex computation, we implemented H/W based post processing system. To verily the Performance of the multi-channel 3D microphone, localization experiments were Performed. The result shows that a front/back confusion, which is the one of common limitations of conventional dummy head technology, can be reduced dramatically.

• 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.