• 한국전자파학회논문지
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• 제19권9호
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• pp.992-999
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• 2008

본 논문은 $20{\sim}100$ MHz 범위의 VHF 대역에서 $50{\mu}s$ 이내에 2 kW 이상의 고전력 신호를 제어할 수 있는 SPST(Single Pole Single Throw) PIN 다이오드 스위치의 설계 및 제작에 관하여 기술하였다. 고전력 스위치 설계에 필요한 설계 요소를 고찰하였고, 시뮬레이션을 통해 설계된 스위치의 삽입 손실, VSWR 및 격리도 특성이 목표 값을 만족함을 확인하였다. 또한, 실험을 통하여 최대 $20{\mu}s$ 이하의 빠른 스위칭 속도로서 2 kW의 고전력 취급이 가능함을 알 수 있었고, 0.2 dB 이하의 삽입 손실, 1.17:1 이하의 VSWR 및 40 dB 이상의 격리도 특성을 얻었다.

• 한국공작기계학회논문집
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• 제17권6호
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• pp.14-22
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• 2008

This study is aimed at suggesting a linear-type diffuser which is excellent in terms of range and elegance like existing diffusers in which amount and direction of wind can be freely controled, out of linear-type diffusers with the highest possibility to be adopted for living space of apartments whose height between floors is not so high and utilizing the linear-type diffuser in design. For the purpose, I examined necessary flow and noise properties of linear-type diffusers. Besides, I evaluated its ventilation capacity for persons in there by applying this in the actual living space. I evaluated features and air blast and found that in time of horizontal and vertical effusion, its T/L ratio is 1-1.5, similar to existing cardioid-type linear diffusers, while in time of slope effusion, it is similar to horizontal effusion in terms of range and it has medium figure in terms of pressure drop and effusion speed, indicating it can provide safe and pleasant indoor environment for persons in there in terms of ventilation.

• 한국식품영양학회지
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• 제24권3호
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• pp.320-328
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• 2011

Information regarding the status of lunch box service for children and juveniles from nutritionally vulnerable families is limited and has not been assessed from the view of beneficiaries. Therefore, this study intended to determine the satisfaction, current status, menu preferences, and dietary habits of recipients served lunch-box meals from Pocheon city. There were 41 subjects from primary schools and 73 from secondary schools. Although 94.8% answered that the foods were generally helpful, as much as 28.9% replied that the amount of food provided was too little. Only 77.2% answered that they eat the foods always or usually, 29.5% answered that they throw away leftover foods, and only 71.9% recycled empty containers, suggesting the need for instruction regarding how to deal with leftover foods and containers. Food preferences were high for deep-fried foods and meats and low for fish and vegetables, and that for vegetable egg rolls was relatively high, suggesting the need to increase vegetable intake. Adherences to guidelines regarding street foods was the lowest in both elementary and secondary school students, suggesting that the contents of nutrition education for these students should include materials to improve dietary habits, along with increasing the consumption of milk.

• International journal of advanced smart convergence
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• 제9권1호
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• pp.70-81
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• 2020

Plastics that we use and simply throw away have a life span of about 500 years and barely decompose. The practice of producing and using common plastics needs to be challenged. Until now, they have been useful in the industrial structure of mass production, but it can be said that there is a lack of research into new materials to introduce and apply in terms of material recycling. As a result of this, we have come to the uncomfortable realization of the fact that we cannot incinerate or reuse these precious resources indiscriminately. No matter how well-designed a product is, it has a competitive advantage if production and consumption activities, waste, collection, sorting and treatment are considered in terms of a continuous cycle, and in this respect, Extended Producer Responsibility (EPR) can help. We are implementing the EPR system, and active industrialization in the field of recycling is required, which is also a challenge for producers to participate actively in recycling and seek to save and recycle resources in design and manufacturing. Against this backdrop, We would like to examine the possibilities, through various studies and developments on product design of recyclable materials, which is being conducted mainly in Europe. In particular, we would like to examine the methods, and value of solving environmental problems and the active efforts to achieve this in the design world, and in particular the case of product design using recycled plastics.

• 한국자기학회:학술대회 개요집
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• 한국자기학회 2003년도 하계학술연구발표회 및 한.일 공동심포지엄
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• pp.90-91
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• 2003

Amorphous magnetic materials with competing magnetic interactions are the subject of current interest. Critical behaviour studies have been performed in order to understand the nature of the phase transition at the Curie point (T$\sub$c/) and type of magnetic ordering below the T$\sub$c/. In some cases there exists a temperature interval in which the magnetic system consists of ferromagnetic grains separated by the paramagnetic interlayers. Magnetic properties of nanoparticles embedded in amorphous matrix also are the subject of recent interest. While these materials exhibit excellent soft magnetic properties at room temperature, some of them have been found to be superparamagnetic in the temperature range above the T$\sub$c/ of the matrix. Thus the role of different magnetic phases in the intergrain magnetic coupling can possibly be taken apart in a sufficiently broad temperature range and investigated separately. In particular materials with competing magnetic exchange interactions show characteristics of enhanced magnetoresistance and softer magnetic properties when magnetic nanocrystals are dispersed in amorphous matrix. We expect careful magnetic measurements in the vicinity of T$\sub$c/ would throw some light on magnetic behaviour of above materials. We present here the FMR analysis of Fe$\sub$82/Mn$\sub$8-x/B$\sub$x/Zr$\sub$10/ alloy near the Curie point.

• 한국운동역학회지
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• 제23권4호
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• pp.327-333
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• 2013

The purpose of this study was to investigate the effects of different types of attentional focus(internal focus vs. external focus) on the dart throwing mechanics. Seven expert dart throwing athletes were assigned to an internal focus group and other seven athletes were assigned to an external focus group. Each group was asked to throw dart either under verbal instruction or without instruction. During dart throwing, accuracy(radial error), consistency(bivariate variable error), dart velocity, acceleration, elbow joint ROM, elbow joint angular velocity, EMD(electromechanical delay), iEMG of biceps brachii and triceps brachii, and CI(coactivation index) were collected and analyzed. Nither instruction type nor instruction itself affected in accuracy and consistency. However, in dart velocity and acceleration, there was an interaction between instruction and attentional focus types. Velocity and acceleration increased in the internal condition, where as they decreased in the external condition. The ROM of elbow joint did not affected by instruction and attention type. However, similar to dart velocity and acceleration, angular velocity increased in internal focus group, while it decreased in external focus group. EMG showed no difference with any condition. In conclusion, internal focus is better than external focus for dart throwing.

• 아동학회지
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• 제4권
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• pp.53-61
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• 1983

The purpose of this study was to investigate the effects of internal-external locus of control on level of aspiration in Korean Children. The locus of control was measured by means of the Nowicki & Strickland's "A Locus of Control Scale for Children (1973)". The level of aspiration was measured by "Throw Balls into the Basket Game" Sixty internal controlled children(30 girls and 30 boys) and 60 external controlled children(30 girls and 30 boys) were selected among 853 children in fifth grade. For the data analysis, two - way analysis of variance and t-test were applied, Pearson correlation coefficient was computed. The results of this study were as follows; 1. Goal discrepancy score were significantly higher in the internal controlled children than in the external controlled children. 2. Shift value were significantly higher in the external controlled children than in the internal controlled children. 3. School achievement were significantly higher in the internal controlled children than in the external controlled children. 4. There was no significant difference in the school achievement between the children who showed high goal discrepancy score and the children who showed low one. 5. There was no significant difference in the locus of control between girls and boys. 6. Goal discrepancy score were significantly higher in boys than in girls, but there was no significant difference in the shift value between girls and boys.

• 한국정보통신학회:학술대회논문집
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• 한국정보통신학회 2012년도 추계학술대회
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• pp.447-449
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• 2012

사실적인 3D game을 만들기 위해 여러 가지 필수 요소가 있는데, 그 중 큰 비중을 차지하고 있는 것이 바로 mapping이다. Mapping은 모델링만으로 감당할 수 없는, 혹은 감당하기 힘든 디테일을 쉽게 추가할 수 있으며 파일의 용량을 줄여 게임 엔진 상에 구현하는데 부하를 줄여줄 수 있다. Mapping의 원리는 3D object에 2D 이미지를 정확히 투영시키는 것인데, 2D와 3D의 기본적 속성 차이 때문에 100% 1:1 매치가 되지 않는다는 문제가 있다. 이를 해결하기 위해 각종 mapping 방법이 개발되고 사용되고 있다. 본 논문에서는 이런 각종 Mapping 방법의 특징과 장단점에 대해 비교 분석하고 어떤 방법이 game개발에 있어서 가장 효율적인지 알아보도록 하겠다.

• 한국해양환경ㆍ에너지학회지
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• 제5권3호
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• pp.3-9
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• 2002

홍수시 강에서 유임되는 폐기물은 육상기인 해양폐기물의 상당량을 차지한다. 강에서 해양으로 유입된 폐기물은 침적폐기물과 부유폐기물로 구분되며, 부유폐기물은 바람이나 해수의 유통에 따라 타지역으로 이동 및 확산되는 특성이 있다. 본 시험은 낙동강에서 유입되는 부유폐기물의 이동경로를 조사하기 위하여, DGPS가 장착된 3개의 부위를 제작, 낙동강 하구에서 투척, 매시간 이동경로를 확인하였다. 시험결과 낙동강에서 유출된 부유 폐기물은 다대포 항주위에 집적되거나 부산항을 거쳐 동해안으로 이동하는 것을 확인하였으며, 조류에 의한 영향보다 바람에 의한 취송류와 해류에 의한 영향이 지배적이었다. 본 시험의 결과를 해양연구원 해양시스템안전연구소에서 개발한 부유폐기물 확산모델(MAPCNTR)과 비교한 결과 비교적 잘 일치하였다.

• 한국잠사곤충학회지
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• 제5권
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• pp.39-42
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• 1965

최청말기에 있어서 산란잠종을 인위적으로 진동을 일으켜 주면, 란내의 의잠은 란각을 벗어날 때, 두부를 내밀고 나와야 할 것인데, 진동으로 인하여 꺼꾸로 미부를 내밀고 나오게 된다. 이때 미부로 나오는 경우는 란각을 벗기지 못하고 의잠의 두뇌부를 씌워진채 있고 이 란각은 자기의 힘으로는 벗기지 못한다. 이러한 상태의 역출란의잠은 진동으로 인하여 나타나는 것인데 그 비율은 정상부화의 약 30％가 된다. 이 역출의잠을 사육하였드니 누에는 잘 자라지 못하고 죽는 누에도 많고 사육성적은 극히 불량하다. 따라서 결론적으로 산란잠종을 농가에 배부할 때는 최청초기에 하거나, 또는 최청말기에 있어서는 난을 진동시키기 않도록 하여야 한다.