• 한국생산제조학회지
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• 제18권5호
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• pp.477-482
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• 2009

This study analyzes the result with dynamic simulation about deformation according to time when a car impacts bollard. These results are shown as followings. The maximum deformation is shown at the lower part of front grass in case of the impact of front or passenger seat but this deformation is shown at the lower part of rear bumper in case of double impact. The maximum equivalent stress is shown at the upper part by the side grass of driver seat at the elapsed time of 0.00075 second after impact in case of the impact of front or passenger seat but this deformation is shown at the front bonnet at the elapsed time of 0.004 second after the additional impact in case of double impact. The maximum total deformation or equivalent stress is shown nearly same in case of the impact of front or passenger seat. But the value of this deformation or equivalent stress in case of the impact of front or passenger seat is shown with 2 times or more than 17% respectively as this value in case of double impact.

• 한국소성가공학회:학술대회논문집
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• 한국소성가공학회 2008년도 춘계학술대회 논문집
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• pp.345-346
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• 2008

Most pedestrian-vehicle crashes involve frontal impacts, and the vehicle front structures are responsible for most pedestrian injuries. The vehicle bumper contacts the lower legs at first. The leading edge of the hood (bonnet) strikes the proximal upper leg and finally, the head and upper torso hit the top surface of the hood or windscreen. In essence, the pedestrian wraps around the front of the vehicle until pedestrian and vehicle are traveling at the same speed. Since the hood surface is made from sheet metal, it is a relatively compliant structure and does not pose a major risk for severe head trauma. However, serious head injury can occur when the head hits a region of the hood with stiff underlying structures such as engine components. The solution is to provide sufficient clearance between the hood and underlying structures for controlled deceleration of a pedestrian's head. However, considerations of aerodynamic design and styling can make it extremely difficult to alter a vehicle's front end geometry to provide more under-hood space. In this study, the safe hood will be developed by designing new conceptual inner panel in order to decrease the pedestrian's head injuries without changing hood outer geometry.

• 대한지역사회영양학회지
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• 제10권6호
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• pp.845-859
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• 2005

The purpose of this study was to investigate the regional differences in food preference among college students participating in a nutrition education program via internet. The subjects were 1672 college students (male: 762, female: 910) and divided into 4 regional groups. A survey using a self-administered questionnaire was conducted using a self-administered questionnaire on taste and food preferences. Data was collected via internet or by mail. Prevalence of the food preferences among regional groups was examined using SPSS statistical package. Food preferences were significantly associated with sex and region. Female students in Chungcheong and Kyungsang areas showed significantly higher preference of the hot taste compared to Seoul and Kyunggi areas. Female students in Seoul, Kyunggi and Chungcheong areas showed significantly higher preference of the boiled bean rice compared to the Kyungsang area. The preference for Kimchi stew of female students in Seoul and Kyunggi was significantly higher than those in Chungcheong and Kyngsang areas. Male students in the Chungcheong area showed significantly higher Preferences of the Young radish kimchi, while female students in this area showed significantly higher preference of the Radish kimchi compared to other areas. The preference for roasted laver of female students in Seoul, Kyunggi and Kyungsang areas was significantly higher compared to the Chungcheong area. The preference for fried chicken of male students in Seoul was significantly higher than that in other areas. The preference for bean sprouts and season bonnet bellflower of male students in Seoul, Chungcheong and Kyungsang areas were significantly higher compared to the Kyunggi area. Therefore, these results Provide nation-wide information on food Preferences among Korean college students. (Korean J Community Nutrition 10(6) : $845\∼859$ 2005)

• 한국자동차공학회논문집
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• 제22권1호
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• pp.36-45
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• 2014

Pedestrian to vehicle traffic accidents show a very high mortality rate compared to the frequency of occurrence. In order to improve the pedestrian protection performance of the vehicle, the korean government added a "pedestrian safety" entry from the year 2007. The performance for pedestrian protection of current vehicles gradually improved compared to the past, but it is still insufficient. It was found that the pedestrian protection performance was very weak, such as the top of the bonnet, the A-pillar and under the front windshield. A application of an active hood and pedestrian protection airbags can be countermeasures for these weak points of pedestrian safety. The active hood and pedestrian protection airbags are designed and manufactured to apply to the top of the hood and to the bottom of the windshield. The manufactured system is equipped in a test vehicle and evaluated based on the Korea New Car Assessment Program(KNCAP) test procedures for the performance of pedestrian safety. As a result, the outstanding effect of pedestrian protection has been achieved by the active hood and the pedestrian protection airbag. The rates of pedestrian injury are reduced by 82.2% and 95.4%, respectively.

• 농약과학회지
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• 제20권2호
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• pp.165-171
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• 2016

도라지와 더덕은 고소득 작물로서 주목받고 있다. 최근 소득을 위해 작물을 연작하는 경우 연작피해로서 뿌리썩음병의 발병이 급속도로 증가하고 있다. 뿌리썩음병은 근채류 식물의 뿌리를 가해하여 큰 경제적 타격을 입히므로 방제가 시급하나 명확한 방제법이 개발되어 있지 않다. 이에 본 연구는 화학약제 tebuconazole EC, trifloxystroim SC, 유기농자재인 자몽 종자 추출물을(GSE) 이용하여 뿌리썩음병 방제 실험을 진행한 결과 더덕에서 친환경제제가 좋은 효과를 보였으나 도라지와 더덕에서 약제의 특성에 따라 큰 차이를 보이지 않았다. 단 재배조건이 배수가 용이한 경우 발병도의 감소와 병방제의 효과가 증진됨을 확인 하였다. 이에 근채류의 뿌리썩음병의 예방 및 방제의 근복적인 대책으로 재배지의 배수가 중요한 원인으로 보여지는 바이다.

• 복식
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• 제60권2호
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• pp.20-34
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• 2010

This study is intended to suggest the characteristic of dress and its ornament introduced in terms of naturalized words on Korean newspapers and magazines published from the age of enlightenment to the Independence(1876-1945). First of all, naturalized words in that period(1876-1945) can be classified into words originated in Japanese, words originated in western countries and borrowed words came from Japan. Borrowed words which came from Japan are almost related to Japan's traditional dress like Gudu, Gabang, Kimono, Nemaki, Ebijahagama, Hagama, Sirusibanden, Doriachi, Dombi, Sarumada, Sseumeeri, Doriachi, and Mombbe. Borrowed words originated in western countries are like Frock coat, Bonnet, Necktie, Chapeau, Scotch, Homespun, Chamois, Skirt, Spring Coat, Ribbon, Silk hat, Panama hat, Handbag, Pajama, Shawl, Apron, Cuffs, Pocket, Handkerchief, Morning coat, Combination-one piece, Rain Coat, Burberry, and Permanent, etc. Borrowed words came from Japan is Lasa[raxa], jokki[jaket], Les[lace], Veludo[velvet], Bbanss[pants], Oba[overcoat], Meliyas[medias], Shass[shirt], Manto[manteau], and Sebiro[civil clothes]. As we can see from the result of research, borrowed words from the age of enlightenment to the Independence was because of its special social situation, Japanese imperialism, they are divided into real western words and words came from Japan or Japanese. In terms of items, a lot of words related to men's suit and women's dress, accessory, etc. It confirms that men's dress was westernized in the whole part compared to partially westernized women's one. A lot of words used at that period are now adapted to Korean language and became the foundation of words used in the current dress and its ornament area.

• 한국산학기술학회논문지
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• 제18권12호
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• pp.729-734
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• 2017

안전릴리프밸브는 배관라인 혹은 탱크의 과도한 압력을 완화하고 사용 적정압력 수준으로 유지해주는 장치이다. 안전릴리프밸브는 스프링 보닛에 통풍구가 대기 쪽으로 혹은 배출구 쪽으로 뚫려 있는지에 따라 배압의 변화에 직접적으로 영향을 받게 된다. 배압은 축적 배압(Built-up back pressure)과 부과 배압(superimposed back pressure)으로 나뉘게 되며 사용조건에 따라 배압의 특성이 달라진다. 본 연구에서 사용되는 안전밸브는 Conventional Safety Relief Valve로써, 배압의 특성을 가정하였다. 또한 개방력과 스프링력 사이의 힘의 평형 방정식을 세워 이론적 접근방법으로 초기 스프링 변위를 구하였다. 디스크가 받는 반력 즉 개방력과 스프링력을 비교하여 블로우 다운을 예측하였다. 블로우 다운은 설정 압력과 디스크 재닫힘 압력 간의 차이다. 본 연구는 ASME 규격 코드에 따라서 블로우 다운 시험 전에 전산 유동해석프로그램 CFX17.1을 이용하여 수치적으로 예측하였음을 밝힌다. 또한 유체-구조 연성해석(fluid-structure interaction analysis)을 통해 안전밸브 트림부의 안전성을 검토하였다. 향후, 시험과 전산수치해석 값을 서로 비교하여 블로우 다운 이론적 접근방법과 유동해석방법을 제안하고자 한다.

• 대한수학교육학회지:수학교육학연구
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• 제19권4호
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• pp.479-491
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• 2009

본 논문은 중등 수학영재를 위한 심화학습 주제로서 데카르트 정리의 도입가능성을 고찰하였다. 데카르트 정리는 오일러 정리와 논리적으로 동치관계가 성립할뿐 아니라, 미분기하의 중요개념인 가우스-보네 정리와도 위계적으로 연결되고 있어 수학적 측면에서 그 가치가 높다. 수학교육적 측면에서도 데카르트 정리는 '다각형의 외각의 합은 $360^\circ$ 이다'라는 평면기하적 성질을 유추적 사고과정을 통해 입체기하적 성질로 일반화하여 지도될 수 있는 주제이다. 이 논문에서는 데카르트 정리의 도입을 위한 방법으로서 엄밀한 증명방법이 아닌 유추적 사고를 통해 재발명할 수 있는 대안적인 방법을 소개하였다.

• 대한수학회보
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• 제60권4호
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• pp.1085-1100
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• 2023

For any given function f, we focus on the so-called prescribed mean curvature problem for the measure e^-f(|x|2)dx provided thate^-f(|x|2) ∈ L¹(ℝⁿ⁺¹). More precisely, we prove that there exists a smooth hypersurface M whose metric is ds² = dρ² + ρ²d𝜉² and whose mean curvature function is ${\frac{1}{n}}(\frac{u^p}{{\rho}^{\beta}})e^{f({\rho}^2)}{\psi}(\xi)$ for any given real constants p, β and functions f and ψ where u and ρ are the support function and radial function of M, respectively. Equivalently, we get the existence of a smooth solution to the following quasilinear equation on the unit sphere 𝕊ⁿ, $${\sum_{i,j}}({{\delta}_{ij}-{\frac{{\rho}_i{\rho}_j}{{\rho}^2+|{\nabla}{\rho}|^2}})(-{\rho}ji+{\frac{2}{{\rho}}}{\rho}j{\rho}i+{\rho}{\delta}_{ji})={\psi}{\frac{{\rho}^{2p+2-n-{\beta}}e^{f({\rho}^2)}}{({\rho}^2+|{\nabla}{\rho}|^2)^{\frac{p}{2}}}}$$ under some conditions. Our proof is based on the powerful method of continuity. In particular, if we take $f(t)={\frac{t}{2}}$, this may be prescribed mean curvature problem in Gauss measure space and it can be seen as an embedded result in Gauss measure space which will be needed in our forthcoming papers on the differential geometric analysis in Gauss measure space, such as Gauss-Bonnet-Chern theorem and its application on positive mass theorem and the Steiner-Weyl type formula, the Plateau problem and so on.

• 한국화재소방학회논문지
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• 제28권4호
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• pp.1-7
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• 2014

자동차의 엔진룸의 내부를 살펴보면 여러 가지의 장치 및 장비가 복잡하게 설치되어 있고 각종 오일 등의 인화물질을 포함하고 있어 재발화 가능성이 매우 높다. 또한, 폭발가능성도 높기 때문에 운전자나 탑승자가 보닛을 열고 엔진룸에 직접 분말 소화기를 분사하는 방식으로는 한계가 있다. 따라서 엔진룸 내부에서 화재를 감지하여 소화약제를 분사한 뒤, 화재를 진화하는 소화시스템과 엔진룸 내부의 고열에 견딜 수 있고, HFC-227ea를 포함하는 충분한 점성을 가진 폼 형태의 소화약제를 개발 및 시험하였다. 그리고 포소화약제가 가지고 있는 소화원리인 질식 및 냉각효과와 HFC-227ea가 가진 부촉매효과를 동시에 이끌어 내고, 소화 후에도 분말 소화기처럼 잔존물에 의한 2차 피해가 없는 맞춤형 소화약제를 개발하였으며, 차량을 이용한 충돌실험을 통하여 방출이 완료된 후에도 이물질 없이 소화약제를 제거할 수 있는 장점이 존재하는 실험결과를 획득하였다.