• 한국항공운항학회지
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• 제19권4호
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• pp.51-57
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• 2011

The spin-up and the spring-back are most severe load cases in the aircraft landing gear design. These load cases are caused by reciprocal action of complex physical phenomenon such as the friction between a tire and ground, inertia of the rotation of a tire and the flexibility of a landing gear structure. Generally, the empirical formula or the theoretical formula is used to calculate the spin-up and spring-back load in the early stage of the development program of the aircraft landing gear. After the materialization of the design of a landing gear, spin-up and spring-back load are acquired by the free drop test. In this study, the spin-up and the spring-back load of the rubber shock absorber type KC-100 nose landing gear are calculated by the explicit finite element analysis. Through this analysis, more accurate and realistic spin-up and spring back loads could be applied to the early phase of the development of the aircraft landing gear.

• Journal of Preventive Medicine and Public Health
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• 제49권6호
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• pp.343-348
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• 2016

Since noncommunicable diseases (NCDs) are generally controllable rather than curable, more emphasis is placed on prevention than on treatment. For the early detection of diseases, primary care physicians (PCPs), as well as general practitioners and family physicians, should interpret screening results accurately and provide screenees with appropriate information about prevention and treatment, including potential harms. The concept of quaternary prevention (QP), which was introduced by Jamoulle and Roland in 1995, has been applied to screening results. This article summarizes situations that PCPs encounter during screening tests according to the concept of QP, and suggests measures to face such situations. It is suggested that screening tests be customized to fit individual characteristics instead of being performed based on general guidelines. Since screening tests should not be carried out in some circumstances, further studies based on the concept of prevention levels proposed by Jamoulle and Roland are required for the development of strategies to prevent NCDs, including cancers. Thus, applying the concept of QP helps PCPs gain better insights into screening tests aimed at preventing NCDs and also helps improve the doctor-patient relationship by helping screenees understand medical uncertainties.

• 한국생활과학회지
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• 제19권5호
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• pp.873-882
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• 2010

Knitwear has become a part of fashion since aristocratic trend-setters of Medieval Spain and France began wearing luxurious silk stockings. However, in more recent times knitwear emerged as a fashion item in the early 20th century when jersey two-piece Channel dresses became popular amongst the French upper classes. Knitwear then evolved into genuine going out clothes through Sonia Rykiel in the 1970s. Sonia Rykiel has made a great contribution to developing knitwear, which she transformed from being used only in informal dresses or clothes for home wear, to a boarder in use in high-quality dresses such as those worn at parties. Unlike most designers who tend to make very different styles each year, she has restricted her clothes to those made with knitwear. The study examined the designs and formative characteristics of her knitwear in order to clarify why Sonia Rykiel's knitwear fashion is apparently so timeless. Results showed that her garments consistently used black oriented color combination, strife patterns, intarsia techniques and application of diversified subordinate materials and other materials that overcome earlier limitations of knitwear. In addition, her designs consistently express the typically Parisian sophisticated urban femininity through practicality, sensuality and playfulness. Overall, her fashion has shown that it exists for women in action through practical design within the scope of demode, the philosophy in her early days, and it has led her to hold great power over knitwear fashion for the past 40 years.

• Journal of Trauma and Injury
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• 제25권4호
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• pp.291-295
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• 2012

Ureteral trauma is rare, accounting for less than 1% of all urologic traumas. However, a missed ureteral injury can result in significant morbidity and mortality. The purpose of this case presentation is to suggest another method for early detection of ureteral injury in blunt traumatic patient. A 47-years-old man was injured in pedestrian traffic accident. He undergone 3-phase abdominal CT initially and had had a short-term follow-up simple. We suspected ureteral injury. Our final diagnosis of a ureteral injury was based on follow-up and antegrade pyeloureterography, he underwent emergency surgery. We detected the ureteral injury early and took a definitive action within 24 hours. In blunt trauma, if abnormal fluid collection in the perirenal retroperitoneal space is detect, the presence of a ureteral injury should be suspected, so a short-term simple X-ray or abdominal CT, within a few hours after initial abdominal CT, may be useful.

• Plant Biotechnology Reports
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• 제3권4호
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• pp.347-353
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• 2009

Procedures that induce microspore embryogenesis have been described for a range of Brassica species, but embryo yield remains low for a number of genotypes. We have carried out experiments with the microspores from a weakly responsive line of B. napus to determine the culture conditions that optimize their in vitro embryogenesis by treating them with effectors of ethylene synthesis and action. The results revealed that isolated microspores subjected to an initial heat stress in a medium supplemented with inhibitors of ethylene synthesis such as AVG and $CoCl_2$ exhibited significantly increased embryo yields. This suggested that regulatory effects are exerted by the ethylene produced by the isolated microspores on the early processes of gametogenesis. As a consequence, treatment of microspores with SAM, an ethylene synthesis precursor, or with the ethylene-releasing agent ethephon, led to decreases in embryo yield. A special response to ethylene during the early stages of microspore development was finally shown to occur through experiments where isolated microspores were treated for increasing periods of time with $CoCl_2$. Collectively, our data demonstrated that the induction of embryogenesis induced by heat stress can be enhanced by inhibitors of ethylene biosynthesis.

• Archives of Pharmacal Research
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• 제26권5호
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• pp.375-382
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• 2003

Effects of ginsenosides on nitric oxide (NO) production induced by lipopolysaccharide plus TNF-$\alpha$ (LNT) were examined in C6 rat glioma cells. Among several ginsenosides, ginsenoside Rd showed a complete inhibition against LNT-induced NO production. Ginsenoside Rd attenuated LNT-induced increased phosphorylation of ERK. Among several immediate early gene products, only Jun Band Fra-1 protein levels were increased by LNT, and ginsenoside Rd attenuated Jun Band Fra-1 protein levels induced by LNT. Furthermore, LNT increased AP-1 DNA binding activities, which were partially inhibited by ginsenoside Rd. Our results suggest that ginsenoside Rd exerts an inhibitory action against NO production via blocking phosphorylation of ERK, in turn, suppressing immediate early gene products such as Jun Band Fra-1 in C6 glioma cells.

• 한국수학교육학회:학술대회논문집
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• 한국수학교육학회 2007년도 제38회 전국수학교육연구대회 프로시딩
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• pp.7-19
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• 2007

During the past 20 years, a small but potentially powerful initiative has established itself in the mathematics education landscape: Mathematics Across the Curriculum (MAC). This curricular reform movement was designed to address a serious problem: Not only are students unable to demonstrate understanding of mathematical ideas and their applications, but also they harbor misconceptions about the meaning and purpose of mathematics. This paper chronicles the brief history of the MaC movement. The sections of the paper correspond loosely tn the typical steps one might take to solve a mathematics problem. The Problem Takes Shape presents a discussion of the social and economic forces that led to the need for increased articulation between mathematics and other fields in the American educational system. Understanding the Problem presents the potential value of exploiting these connections throughout the curriculum and the obstacles such action might encounter. Devising a Plan provides an overview of the support systems provided to early MAC initiatives by government and professional organizations. Implementing the Plan contains a brief description of early collegiate programs, their approaches and their differences. Extending the Solution details the adoption of MAC principles to the K-12 sector and throughout the world. The paper concludes with Retrospective, a brief discussion of lessons learned and possible next steps.

• 한국발생생물학회지:발생과생식
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• 제22권4호
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• pp.351-360
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• 2018

The adipogenesis is a maturation process of pre-adipocyte cell into mature lipid-filled adipocyte cell. The adipogenesis begins at the late prenatal stage and continues until the early postnatal age. Because the adipogenesis and formation of adipose tissue persist during postnatal period and are precisely regulated by the action of numerous gene products, the present research was attempted to determine the expressional patterns of adipose tissue-associated genes in the rat epididymal fat pad at different postnatal ages, from 7 days to 2 years of ages, using a quantitative real-time PCR analysis. The basal expression levels of CCAAT/enhancer binding protein gamma, sterol regulatory element binding transcription factor 1, fatty acid binding protein 4, adiponectin, leptin, and resistin at the early postnatal ages were significantly lower than those at the elderly ages, even though a fluctuation of expressional levels was observed at some ages. The lowest expressional level of delta like non-canonical Notch ligand 1 was detected at 44 days and 5 months of ages. The expression of peroxisome proliferator-activated receptor gamma ($PPAR{\gamma}$) was the highest at 44 days of age, followed by a diminished expression of $PPAR{\gamma}$ at the elderly ages. These results indicate the existence of a complex regulatory mechanism(s) for expression of adipose tissueassociated genes in the rat epididymal fat during postnatal period.

• 비파괴검사학회지
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• 제36권3호
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• pp.181-187
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• 2016

화력발전용 보일러 내부에는 연소열을 고온 고압의 스팀으로 변환하기 위한 열교환 튜브가 복잡한 형태로 배치되어 있다. 이 튜브에서 누설이 발생할 경우 고압의 스팀에 의해 치명적인 고장과 발전 정지를 초래하며, 누설 발생 여부를 조기에 검출하지 못할 경우 인근 튜브의 손상까지 연쇄적으로 발생하여 조기에 튜브 누설을 검출할 수 있는 기술 확립이 필요하다. 본 논문에서는 기존 보일러 튜브 누설 감시 설비(BTLD)에 음향방출(AE) 기술을 적용하여 기존 시스템 대비 미세누설을 검출하고 조기에 경보를 발생시킬 수 있는 시스템에 대해 개발을 하였다. 또한 이 시스템을 검증하기 위해 실제 운전 중인 560 MW급 화력발전소 보일러에서 다양한 크기(ⵁ2, ⵁ5, ⵁ10 mm)의 모의 누설시험을 실시하였으며, 그 결과 기존 시스템에서는 검출하지 못하였던 미세누설(ⵁ2 mm, ⵁ5 mm)에 대해 개발된 시스템은 조기에 경보를 발생(18 dB 이상 신호 상승)시킬 수 있음을 확인하였다.

• 융합정보논문지
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• 제9권6호
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• pp.153-163
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• 2019

본 연구의 목적은 초기 청소년의 삶의 만족도에 미치는 영향과 그 과정에서 행동적 공격성의 매개효과를 검증하는데 있다. 이를 위해 서울지역의 강남과 강북 및 경기도 성남시에 소재한 초등학교 일부를 선택했으며, 그 중에 초등학교 4-6학년 재학생 중인 초기 청소년 290명을 표본으로 추출하여 구조방정식을 실행하였다. 연구결과를 살펴보면 첫째, 초기 청소년의 개인요인인 자아존중감은 삶의 만족도에 정(+)적인 영향을 미치며, 행동적 공격성에는 부(-)적인 영향을 미치는 것으로 나타났다. 둘째, 우울감은 삶의 만족도에 부(-)적인 영향을 미치며, 행동적 공격성에는 영향을 미치지 않는 것으로 나타났다. 셋째, 초기 청소년의 행동적 공격성에는 삶의 만족도에 부(-)적인 영향을 미치며, 자아존중감과 삶의 만족도 사이에 부분매개효과가 있는 것으로 나타났다. 하지만 우울감과 삶의 만족도 사이에서는 매개효과가 없는 것으로 나타났다. 이상의 연구결과를 바탕으로 초기 청소년의 삶의 만족도를 높여주고, 행동적 공격성을 낮추기 위한 프로그램의 개발과 적용을 제시하였다.