• Journal of information and communication convergence engineering
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• 제8권3호
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• pp.263-266
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• 2010

In this paper, a novel defected ground structure (DGS) pattern with enhanced effective capacitance (varactor diode) and a hole in PCB center is presented. The increase in effective capacitance enables the new DGS pattern to achieve a lower resonance than the DGS pattern for the same etched square dimension. The hole in the center also can make resonator frequency lower with better characteristic. According to the tunable characteristic of varactor diode, the resonant frequencies can be tunable. Simulation results show that a lower resonance is achieved with active device, compared to a common DGS pattern.

• 한국태양에너지학회 논문집
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• 제35권1호
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• pp.69-80
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• 2015

A series of numerical analyses was conducted to predict the thermal performance of a solar air heater depending on the hole configuration and geometry in the absorber plate. The planar dimensions of the prototype were 1 m (W) by 1.6 m (H), and the maximum air flow considered was $187m^3/h$. It was considered that protruding holes with a triangular opening in the absorber plate would invoke turbulence in the air flow to enhance the convection heat transfer. Six different hole configurations were investigated and compared with each other, while the hole opening height was considered as a design variable. Three-dimensional transient analyses were performed with a commercial software package on the airflow and heat transfer in the model. The numerical results were analyzed and compared from the view point of the outlet air temperature and its time response to derive the optimal hole pattern and hole opening height.

• 한국광학회지
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• 제31권3호
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• pp.148-154
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• 2020

본 논문에서는 주기적인 구멍배열(periodic hole array, PHA) 패턴을 가진 나노금속구조 컬러필터의 문제점인 입사광의 각도에 따른 컬러필터 중심파장의 이동을 해결하기 위해 새로운 구멍 패턴인 polyperiodic hole array (PPHA)를 제시한다. 먼저 녹색파장대역 컬러필터를 만들기 위해 구멍의 직경과 주기를 정했으며 propagation length와 skin depth를 고려해 단위셀의 크기, 금속과 유전체의 두께를 설정했다. PPHA 패턴을 만들기 위해 주기적인 구멍배열을 국부적으로 회전시켜 전체적으로는 비주기적이지만 부분적으로 주기적인 패턴을 만들었다. 그 결과 PHA 패턴과 대비하여 PPHA 패턴 나노금속구조 컬러필터는 입사광각이 0°에서 30°까지 증가하였을 때 파장의 이동도가 최대 40% 개선되었다. 본 연구를 통해 나노금속구조 컬러필터의 성능을 향상시킬 수 있으며 디스플레이, 이미지 센서 등 이미징 디바이스 분야에 접목시켜 산업적으로 활용할 수 있을 것으로 예상한다.

• 복식문화연구
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• 제15권6호
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• pp.1038-1052
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• 2007

The purpose of this study is to analyze present the pattern making of the lining fabrics calculating the right ease and rising quantities of arm-hole when the pattern of the lining fabrics of stretchable jacket fabrics is produced. The outcomes of this study are as follows. The right ease of lining fabrics was not room of 0cm as patterns being same the right side of fabrics in the girth of the chest, waist, and the edge of a garment and gets the most excellent valuation, and then the girth of the chest, and waist was applied to 2cm and around the edge of a garment 0cm in regular lining fabrics. In addition to, although the ease of patterns of the lining fabrics was more, it was not necessarily to satisfy. The result of the valuation according to the quantities of rising arm-hole of the pattern of the lining fabrics showed that the making lining fabrics that the quantities of rising arm-hole was 0.8cm in the body and 1.2cm in the sleeve in the both the stretchable fabrics and regular lining fabrics was the most excellent thing, and then 0cm in the body and 2cm in the sleeve, and then 0cm in the body and 0cm in the sleeve. The valuation of external appearance on the quantities of rising arm-hole was recognized similarly because of being rarely significance level, but around the chest and waist was recognized as being significance level in wearing satisfaction.

• Smart Structures and Systems
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• 제17권5호
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• pp.725-742
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• 2016

This paper is focused on stiffness ratio effect and a new method to specify the best pattern of piezoelectric patches placement around a hole in a plate under tension to reduce the stress concentration factor. To investigate the stiffness ratio effect, some different values greater and less than unity are considered. Then a python code is developed by using particle swarm optimization algorithm to specify the best locations of piezoelectric actuators around the hole for each stiffness ratio. The results show that, there is a line called "reference line" for each plate with a hole under tension, which can guide the location of actuator patches in plate to have the maximum stress concentration reduction. The reference line also specifies that actuators should be located horizontally or vertically. This reference line is located at an angle of about 65 degrees from the stress line in plate. Finally two experimental tests for two different locations of the patches with various voltages are carried out for validation of the results.

• 한국의류학회지
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• 제27권11호
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• pp.1190-1197
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• 2003

The purpose of this study is to compare and analyze methods of women's apparel prototypes and provide for some useful fundamental data to improve the apparel prototype suitable for Korean women. Two different drafting methods, the Bunka pattern of Japan Bunka Women's University and the Secoli pattern of Italy istituto carlo secoli, an italian pattern drafting institute, were selected. The result and discussion are as follows; In the calculation formula, the Bunka was shown more comfort at arm-hole part, because of it's lower arm-hole depth, wider arm-hole width and lower cap height in comparison with the Secoli. At the shoulder angle, the Bunka is inclined more in front shoulder than the back shoulder, whereas the Secoli is inclined more in back shoulder than the front shoulder. It could explain that the Bunka is suitable for bendforward type and the Secoli is suitable for lean-back type. In the sensory test, the one-piece pattern of the Secoli with 4cm ease was highly estimated in ease. It seems young women's preference to body conscious clothes which reflected in many new elastic fabrics. At the bust point to neck, the Bunka was highly estimated, compared with the Secoli. It seems like to be caused that for the bust point to neck formula, the Bunka used bust girth, the Secoli used stature which has low correlation with the bust point to neck.

• 한국의류학회지
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• 제24권2호
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• pp.164-172
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• 2000

The purpose of this study was to investigate the most appropriate arm-hole depth in 9 positions of arm movements. This subjects were four females, college students aged 18 to 23 years old. The clothing size 55 was used for this study. In the experiments for the investigation of the arm-hole depth, the evaluations were performed for aesthetic view, clothing adaptability to arm movements, and quantity of materials pulled up by 9 movements of arm. The results of this study were as follows: 1) In the aesthetic evaluation, there were no significant differences in arm-hole depths. 2) In the evaluation of clothing adaptability to arm movements, the experiment clothes, in which-arm-hole depths were raised, had more positive evaluations especially with the increasing the angle of arm movements. 3) In the evaluation of clothing adaptability to each body areas, there were no significant differences in all body areas except upper arm circumference blade. 4) In the evaluation of quantity of materials pulled up by arm movements, the clothes of B/4-2 arm-hole depth had the least amount pulled up by arm movements, which showed the highest adaptability to arm movement.

• Journal of Welding and Joining
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• 제16권5호
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• pp.108-118
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• 1998

This study proposes th analysis and evaluation method of time series ultrasonic signal using the chaos feature extraction for ultrasonic pattern recognition. Features extracted from time series data using the chaos time series signal analyze quantitatively weld defects. For this purpose, analysis objective in this study is fractal dimension and Lyapunov exponent. Trajectory changes in the strange attractor indicated that even same type of defects carried substantial difference in chaosity resulting from distance shifts such as 0.5 and 1.0 skip distance. Such differences in chaosity enables the evaluation of unique features of defects in the weld zone. In quantitative chaos feature extraction, feature values of 4.511 and 0.091 in the case of side hole and 4.539 and 0.115 in the case of vertical hole were proposed on the basis of fractal dimension and Lyapunov exponent. Proposed chaos feature extraction in this study can enhances ultrasonic pattern recognition results from defect signals of weld zone such as side hole and vertical hole.

• 한국지반공학회논문집
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• 제19권2호
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• pp.75-85
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• 2003

화약폭발로 발생한 응력파 전파특성을 파악하기 위하여 화약종류, 장약조건, 전파매질조건 별로 실내 모형시험 및 현장 암반시험과 수치해석을 시행하였다. 수치해석은 시험조건과 동일한 조건을 모델링하여 시행하였다. 2공을 동시 발파하는 경우에 2공 중심에서 응력크기는 1공 발파보다 2배정도로 증가되었다. 최대응력 도달시간은 디커플링장전조건이 밀장전조건보다 2배정도 지연되어서 가스압력에 의해 최대 응력이 발생하였다. 시험결과와 수치해석결과를 비교.분석한 결과 수치해석결과가 시험결과보다 약간 저평가되었지만 비교적 유사하여 수치해석으로 발파결과를 미리 예측할 수 있었다. 도로터널의 일반적인 발파패턴도에 대하여 수치해석을 시행하고 외곽공과 외곽공과 인접한 확대공 발파로 인하여 발생하는 동적 암반거동 및 암반손상을 평가하였다. 수치해석결과 확대공의 손상영역이 외곽공보다 크게 나타났다. 확대공 손상영역을 감소시키기 위하여 낮은 밀도의 화약사용, 디커플링장전, 확대공과 외곽공사이의 거리 증가 등의 방안을 제안하였다.

• 대한조선학회지
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• 제3권1호
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• pp.11-18
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• 1966

In a polarized light field, triangular plate bracket specimen of CR-39 with lightening hole were subjected to tension. The variables of the models used in the experiment were taken in the range of length-depth $ratio=0.583{\sim}1.715$, eccentricity of lightening hole from the geometrical center of $bracket=-1/4"{\sim}+1/4"$, and the lightening hole $diameter=1/2"{\sim}2"$. The isoclinics were drawn and from those the stress trajectories were constructed. Then the distributions of boundary stress around the lightening holes were determined from the isochromatic fringe pattern. The conclusions reached in this investigation are as follows: 1. Maximum stresses of the hole boundary are gradually increased when the diameter of the lightning hole increase. 2. Maximum stresses of the lightning hole boundary are decreased gradually when the eccentricity of the lightning hole from the geometrical center of the bracket to the farther side from the free end. 3. If the minimum distances from the free end of the brackets to the lightening hole boundaries are equal, the variation of the maximum stresses are in a small range for the change of lightening hole diameter and its location. 4. When the length-depth ratios are smaller than 0.8, the maximum stresses increase steeply. In the range of $0.8{\sim}1.2$ maximum stresses increase gradually and thereafter increase rapidly when the length-depth ratio of the bracket increase for the same diameter of a lightening hole.