• 한국정밀공학회지
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• 제26권12호
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• pp.123-130
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• 2009

This study presents the application of a polymer behavior model that considers fluid mechanics and heat transfer effects in a deposition system. The analysis of the polymer fluid properties is very important in the fabrication of precise microstructures. This fluid behavior model involves the calculation of velocity distribution and mass flow rates that include the effect of heat loss in the needle. The effectiveness of the proposed method was demonstrated by comparing estimated mass fluid rates with experimental values. The mass fluid rates under various process conditions, such as pressure, temperature, and needle size, reflected the actual deposition state relatively well, and the assumption that molten polycaprolactone(PCL) is a non-Newtonian fluid was reasonable. The successful fabrication of three-dimensional microstructures demonstrated that the model is valid for predicting the polymer behavior characteristics in the microstructure fabrication process. The results of this study can be used to investigate the effect of various parameters on fabricated structures before turning to experimental approaches.

• Tribology and Lubricants
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• 제36권5호
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• pp.274-278
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• 2020

This study investigates the possibility of reducing squeal noise generated at the contact point between an elastomer and glass by using the properties of a magneto-rheological elastomer (MRE) whose stiffness changes with the application of a magnetic field. Previously, squeal noise was mainly observed in the unstable section caused by the weakening of friction due to velocity. Previous studies have shown that squeal noise decreases as the stiffness increases. Accordingly, this study is conducted to control the unstable area of the friction curve and to reduce the noise by inducing the stiffness change of the MRE by applying a magnetic field. The friction, vibration, and noise characteristics are measured using a reciprocating friction tester. The frequency ranges of vibration and noise measured with the accelerometer and sound sensor show similar results. When a magnetic field is applied to the MRE, there is significantly lower noise compared with the case without the application of the magnetic field. The average coefficient of friction decreases with the application of the magnetic field. The maximum coefficient of friction increases rapidly at the turning point and decreases when the magnetic field is applied. This shows that the mechanical properties of the MRE change due to the magnetic field, and the noise and friction coefficient also decrease.

• 수산해양기술연구
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• 제51권2호
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• pp.257-264
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• 2015

This study is intended to provide navigator with specific information necessary to assist the avoidance of collision and the operation of ships to evaluate the maneuverability of dead weight tonnage 8,000 tons Oil/Chemical tanker. The actual maneuvering characteristics of ship can be adequately judged from the results of typical ship trials. Author carried out sea trials based full scale for turning test, Z" maneuvering test, man overboard rescue maneuver test, inertia stopping test. Consequently, $2^{st}$ Overshoot yaw angle of the semi balanced rudder and flap rudder in ${\pm}20^{\circ}$ zig-zag test showed $22.2^{\circ}$ and $18.0^{\circ}$, respectively. The maneuverability of the vessel was good in the flap rudder. The man overboard rescue maneuver maneuverability test was most favorable in the flap rudder and the full load condition. The results from tests could be compared directly with the standards of maneuverability of IMO and consequently the maneuvering qualities of the ship is full satisfied with its.

• 대한전자공학회논문지SD
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• 제37권10호
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• pp.25-32
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• 2000

본 연구에서는 강유전체의 이력 특성을 정밀하게 계산하기 위한 모델을 제공하였다. 본 모델은 2중 전위우물에 근거한 반경험적 분극 천이 모델에 기초하고 있으며 프라이사흐의 이력 함수의 분포 모델의 물리적 특성과도 잘 일치되고 있음을 보였다. 본 모델은 강유전체 이력 특성의 천이 경사도와 임프린트 특성을 고려하고 있으며 인가 전압의 극성이 바뀌는 경우에 발생되는 부 이력 경로에 대해서도 정확하게 분극 전하의 변화를 표현하고 있음을 보였다. 본 모델의 예측 결과는 PZT와 SBT의 두 종류의 강유전체에 대해서 측정 결과와 잘 일치하고 있음을 보였다. 또한, 본 모델을 AHDL 코드로 구현하여 스펙트레 시뮬레이터를 통하여 회로 설계를 할 수 있는 환경을 제공하였다.

• Child Health Nursing Research
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• 제8권4호
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• pp.458-468
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• 2002

The purpose of this study was to identify metacommunicative behaviors between nurses and patients in a pediatric unit. The research method included observation using videotaping. Data were collected from December, 2001 to February, 2002. Total six nurses, and eight patients and their mothers in a pediatric unit participated in this study. The interactions were videotaped under the participants' consent. The participants were observed for total 8 hours over 2-day period. Special episodes which were identified as metacommunicative behaviors in the taped interactions were transcribed. Transcription included verbal and nonverbal interactions. Selected episodes were classified using Mitchell's definition. Each classified definitions were named, and categorized by its purpose. The results were as follows: Nineteen metacommunicative behaviors which used frequently by nurses-approaching, mediating eye level, eye contact, touching, encouraging, turnabout, mimic voice, giving choices, friendly demand, expansion, tagging, repeating and confirming, identification, reflection, baby talk, symbolization, description of acts, relaxed posture, turning away- were identified and organized into four categories. They were call for attention, facilitating response, empathy, and tension release. In conclusion, nurses in this study used metacommunicative behaviors frequently and these behaviors were effective in interacting with children. It is suggested that any educational programs to teach communication skills to nurses need to include techniques on metacommunicative behaviors. This will help nurses to be more sensitive to different characteristics of their patients.

• 교육시설 논문지
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• 제22권4호
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• pp.15-25
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• 2015

The Olin Library in St. Louis was an important design competition for the United States in the 1950's, the rear of America's modern architecture. The participants of this competition were a variety of representative architects and groups of its time. With the library's functional rationality, the Olin Library competition was legible of the aspects of modern architectural flow. The competition required two demands. The first demand was absolute importance in character definition of place, which was to satisfy the site conditions approached from campus design. Secondly was related to interpretation of morphological symbolism in an architectural matter. The experiments of American modern architecture started to change its ideal goal gradually ; accommodating the altering public's code, at the same time, maintaining the original modern value was the reason to changing the ideal goal. As a turning point, the Olin Library should be understood as an important work, which divulged the value change of architectural interpretation.

• Journal of East-Asian Urban History
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• 제1권
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• pp.7-24
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• 2019

A. J. Toynbee published a book called Travel to China(1931) after traveling around the Asian continent in 1929. The book mostly focuses on Japan, China and the relationship between the two countries. Toynbee visited major cities in Japan and China by train. Most of the Japanese cities he saw were turning into modern cities in the process of spontaneous modernization mixed with its tradition. On the other hand, Chinese cities that he visited showed him various characteristics, including traditional, colonial, or semi-colonial cities. The modern cities of Japan and China in the late 1920s were transformed into various aspects under the influence of tradition, spontaneous modernization, colonial or anti-colonial modernization. How did Toynbee look at cities in East Asia? How did he recognize the relationship between tradition, modernization and colonization while visiting this area? Toynbee emphasizes the weight and influence of tradition especially in the development of modern cities in Japan and China. So, are modern European cities born out of their own traditions? Modern cities everywhere in the East and West were newly developed under the influence of tradition. Toynbee's attitude, which emphasizes especially its tradition in the modern cities of East Asia, seems to reflect his Orientalistic view.

• 복식
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• 제54권5호
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• pp.27-39
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• 2004

Since around 1990. some experimental and shocking ugliness images have been expressed in Fashion and Make-up as well as Fine arts. The purpose of this study is to investigate the trends of ugliness images expressed in Modern Make-up from 1995 to 2003, especially focusing on color, and to enlarge the expressions through formative elements and to anticipate the prospect of Make-up in the future. Ugliness is the most negative aesthetic value which is lack of beauty. The 20 century art trends representing the ugly shape have been distorted or deformed or destroyed and extremely exaggerated with yellow, red, black, blue, white, green. The image and color of ugliness can be summarized as historical, avant-garde, decadence, de-constructive, humorous, futuristic trend and Most of colors are the achromatic ones like black, white, dark gray and red. blue, dark brown and so on. These colors cause some negative attributes such as fear. anger, death, devil, Pain, bad, ill omen, sorrow, despair and the like. At the turning Point in 21C are to be extended the range of color according to the experimental attempts such as informal, collage, graphic and the forth. Lastly, The characteristics of ugliness images expressed in the color of Modern Make-up have been analyzed into formlessness and inaccuracy and deformation by Karl Rosenkranz＇s theory.

• 수산해양교육연구
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• 제27권3호
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• pp.747-756
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• 2015

Brown alga Undaria peterseniana has been interested in the commercial scale aquaculture for warm water species development in southern coastal area of Korea. However, this species was classified an endangered species caused by a decrease in habitat and natural population. In this study, inhabit characteristics of U. peterseniana was investigated in their natural habitat of Ulleung Island, Korea. The U. peterseniana population was occurred dense patches at 20~30m depth. Total length of the alga reached 1.0~2.0m and the largest width ranged 10.0~35.0cm during the study. In 2013, habitats of this species increased two sites compared with the previous year and their distribution extended to low depth (10m) of coastal area. In long-term data, seawater temperature revealed a continuous increment by strong going north of East Korea Warm Current or Ulleung Warm Eddy turning around the coast of Ulleung Island. It suggested that habitat extension of U. peterseniana may be caused by suitable settlement condition and increase of warm water around the coastal area. Current studies of this species may be continuously required in the possibility of fisheries resources as aquaculture species and index species of increment of water temperature at the fixed monitoring site in East Sea. This is the first study to research ecological feature U. peterseniana population at the natural habitat of Ulleung Island.

• 대한전자공학회논문지SD
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• 제48권6호
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• pp.33-38
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• 2011

최근들어 모바일기기의 다기능화 와 고성능화로 인하여, 배터리 사용량이 증가하고 있다. 하지만 필요한 컴퓨팅 파워에 비하여 배터리의 에너지 용량증가의 연구는 더디게 진행되고 있다. 그러므로 본 논문에서는 우리는 배터리 방전특성을 이용하여, 배터리의 사용가능 유효용량을 증가시키는 연구를 하였으며, 무선 전송에서 시스템파워를 끄는 것만으로 배터리 사용시간 연장을 하는 기술을 설명한다. 실험은 표준영상 전송을 통하여 배터리 방전간격에 따른 배터리 사용시간을 측정하고, 사용될 어플리케이션과 발견적 실험을 통하여 배터리 사용시간의 최적화를 달성하였다.