• 한국화재소방학회논문지
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• 제26권6호
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• pp.7-14
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• 2012

본 연구에서는 화재현장에서 유류와 관련되어 실화나 방화의 매개체로 사용되어 화재가 발생했을 때 석유류의 정확한 분석기법을 개발하기 위하여 발화지점 주변의 온도분포, 연소되고 남은 물질의 흔적과 GC/MS 분석으로 물질의 종류를 확인하는 것을 가연성 고체와 비교해서 실험하였다. 연구결과 천장에 도달하는 온도는 휘발유와 시너는 점화되자마자 불꽃이 생성되어 천장의 온도가 매우 빠르게 상승하여 그곳에 물질이 있을 경우 2차 화재발생이 전개될 것으로 나타났다. 연소된 후에 바닥에는 가연성 고체와 유류가 상이한 특징적인 패턴을 형성하였다. 연소된 장판은 탄화수소계열이지만 가스검지관을 통해 반응을 확인한 결과 가연성 고체는 아무런 반응을 띠지 않았으나 유류는 즉시 반응을 하였고 그 연소물질을 7일이 경과된 후에 GC/MS로 분석한 결과 유류의 존재를 확인할 수 있었다. 화재조사가 복잡한 과정이지만 물질의 특성을 통한 세밀한 조사는 유류화재를 입증하는 데 중요하고 GC/MS분석기기를 통해 실체를 확인하는 과정이 요구된다.

• Journal of Plant Biotechnology
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• 제44권4호
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• pp.478-483
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• 2017

기내배양한 감자에 1일, 2일, 3일간 저온처리 후 저온관련 유전자의 발현양상을 조사하였다. 저온 처리 기간이 늘어날수록 PPI1, CI21B유전자의 발현양은 증가하였고, CBF4, CI21A 유전자의 발현양은 감소하였다. 또한 CI21A와 CI21B유전자의 잎, 줄기, 괴경에서 명 처리와 암 처리 기간별로 저온 처리기간에 따른 유전자의 발현의 차이를 보았다. 이에 근거하여 감자 정아의 동결과정 중에서 LS단계와 PVS2 단계에서 AFP를 농도별로 처리하였다. 그 결과, 저온처리 기간이 늘었을 때의 유전자 발현양상과 AFP 특정 농도에서의 발현 양상이 동일하였다. LS단계에서는 1,500 ng/ml AFP 처리와, PVS2단계에서 500 ng/ml AFP 처리가 감자 정아의 초저온동결보존에 효과적이라는 것을 유전자의 발현 양상으로 확인하였다.

• 미생물학회지
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• 제22권1호
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• pp.1-18
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• 1984

1976年 3月부터 1977年 2月까지 滿 12個月동안 榮山江 汽水域 39個 場所로부터 採水한 156個 water sample로서 酵母의 季節的 分布와 度包配에 따른 이들 酵母의 分布型을 調査하였다. 酵母의 全體 平均値는 100ml당 52에서 487個의 生菌數를 보여주었고 가장 많은 個體數는 春季에 있었고 가장 적은 個體數는 夏季에 있었다. 14屬 83種에 해당하는 933個의 酵母와 한 種의 酵母樣 곰팡이가 分離되었는데 基中 Candida가 29%, Debaryomyces가 17.3%, Rhodotorula가 16%, Saccharomyces가 14%이었고 나머지 다른 屬들은 10%以內이었다. Debaryomyces hansenii와 Rhodotorula glutinis가 全水域에서는 물론 年中 優點種이었고 총 好氣性細菌集團의 크기, 陸水流入量, 그리고 몇가지 지형적 기후적 요소들이 汽水환경에서 酵母의 季節的 分布는 물론 種의 組成을 反映하는 같다. 酵母의 平均數, 種의 多樣性 特히 醱酵性 및 爲菌系形成 母酵들의 數는 감度가 감소함에 따라 增加한 反面 질산염 利用酵母들은 위와 相反된 경향을 보여주었는데 이는 汽水域에서 酵母의 分布型을 認識하는데 감度勾配가 바람직한 看破 요소로서 利用될 수 ㅣ있음을 시사하고 있다.

• 자원환경지질
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• 제17권1호
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• pp.49-55
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• 1984

유도 분극법에서 지하의 경사 물체에 대한 3차원 표준곡선을 해석하였다. 이들 물체 대한 쌍극자 IP 응답은 적분 방정식을 이용한 수치계산 방법으로 구해졌다. 이때 물체의 경사각은 각각 0,20. 45,70 및 90도 이다. 물체가 수평 (경사각 0 도) 및 수직(경사각 90도)일 때는 단면도에서 대칭성 IP 패턴이 되지만, 20, 45 및 70도로 경사하고 있을 때는 최대값의 등치선이 물체의 경사 방향과 반대 방향으로 기울어져 있는 비대칭성 패턴을 나타낸다. 이중 가장 현저한 비대칭성 패턴은 20도 경사 모델에서 나타났다. 쌍극자 IP 데이터로서 70도 경사물체와 수직물체를 식별하기는 어렵다. 또한 측선이 물체의 중심에서 주향방향으로 멀어질 때의 반응은 IP anomaly가 작은 값으로 단면도에서 보다 깊은 곳에 나타나게 된다. 한편, 탐사대상물의 위치를 추정할 때 평면도는 단연도보다 유용할 것으로 생각된다.

• Wind and Structures
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• 제30권5호
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• pp.465-474
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• 2020

Vortex-induced vibrations of a yawed flexible cylinder near a plane boundary are numerically investigated at a Reynolds number Re_n= 500 based on normal component of freestream velocity. Free to oscillate in the in-line and cross-flow directions, the cylinder with an aspect ratio of 25 is pinned-pinned at both ends at a fixed wall-cylinder gap ratio G/D = 0.8, where D is the cylinder diameter. The cylinder yaw angle (α) is varied from 0° to 60° with an increment of 15°. The main focus is given on the influence of α on structural vibrations, flow patterns, hydrodynamic forces, and IP (Independence Principle) validity. The vortex shedding pattern, contingent on α, is parallel at α=0°, negatively-yawed at α ≤ 15° and positively-yawed at α ≥ 30°. In the negatively- and positively-yawed vortex shedding patterns, the inclination direction of the spanwise vortex rows is in the opposite and same directions of α, respectively. Both in-line and cross-flow vibration amplitudes are symmetric to the midspan, regardless of α. The RMS lift coefficient C_L,rms exhibits asymmetry along the span when α ≠ 0°, maximum C_L,rms occurring on the lower and upper halves of the cylinder for negatively- and positively-yawed vortex shedding patterns, respectively. The IP is well followed in predicting the vibration amplitudes and drag forces for α ≤ 45° while invalid in predicting lift forces for α ≥ 30°. The vortex-shedding frequency and the vibration frequency are well predicted for α = 0° - 60° examined.

• 복식문화연구
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• 제11권3호
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• pp.367-374
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• 2003

When analyzing forms in the human body and clothes, we conceptualize each part into a cone, sphere, and cylinder, and the esthetic characteristics of our fashion culture and esthetic fashion characteristics of Koreans are composed by expressing with universal images such as circle, square, and triangle when forms are expressed in a plane. To determine how the structural principle of shapes that are the shapes of all things and basic to geometry, i.e., circle, square, and triangle, applies to clothes that cloth our body called the small cosmos, we discussed the symbolic meaning hidden inside the structure of Korean clothes based on the basic pattern drafting method of Korean men’s traditional trousers. We drew the conclusion that Korean men's trousers composed of circles, triangles, and squares express the five elements diagram through their plane structure, are designed in circles with cones and pyramids, and are made to well express the principle of the small cosmos of our body. Moreover, when the basic pattern of Korean men’s trousers explained with the antipathy diagram is viewed to create all things while maintaining opposite and complementary relationship with Sangsang (mutually benefitting factor), it would be correct to say that the principle of the top verse the bottom is viewed as conflicting. From the structural point of view, since the philosophy of the Samsu principle (the principle of 1, 2 and 3 in which 1 represents the heaven, 2 represents the earth, and 3 represents the people) is hidden in Korean men's trousers in which Hurimalgi (the part of trousers corresponding to the waist band of Western pants) is the circle representing the heaven, Marupok is the square representing the earth, and Sapok is the triangle representing the people, we could look at deep meaning of our ancestors expressed in our clothes.

• 한국도로학회논문집
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• 제16권6호
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• pp.69-78
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• 2014

PURPOSES : The purpose of this paper is showing that the state of pavement sublayers can be evaluated differently according to direction of FWD. METHODS : The concrete pavement slabs above subgrade without anything, subgrade with cavity, and box culvert were modeled by finite element method(FEM). The modeled pavements were analyzed by changing the direction of falling weight deflectometer(FWD). The deflection results obtained from FEM were used to calculate radius of relative stiffness and composite modulus of subgrade reaction using AREA method. Then, the analyzed results were compared to the results of the test performed at the Korea Expressway Corporation(KEC) test road. RESULTS : The composite modulus of subgrade reaction increased with subgrade elastic modulus, while radius of relative stiffness decreased. The pavement sections of pure earth showed the consistent results regardless of FWD direction. In case there was cavity, the radius of relative stiffness was larger and composite modulus of subgrade reaction was smaller when FWD was leaving the cavity than when approaching the cavity. This pattern became clear when the cavity got larger. In case of the section with box culvert, the pattern was opposite to the case of cavity. When the soil cover depth increased, the effect of box culvert got smaller. When the load was applied far from the cavity and box culvert, the effect was also declined. The test performed at the KEC test road showed identical results to those of finite element analysis. CONCLUSIONS : The direction of FWD should be considered in evaluation of the state of pavement sublayers because it can be evaluated differently even under identical condition.

• 한국전자파학회논문지
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• 제28권4호
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• pp.251-260
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• 2017

이 논문은 NLJD 시스템에 적용될 수 있는 스파이럴 안테나의 축비 개선을 위한 접지면 위의 슬릿 설계에 관하여 기술한다. 이 논문에서 제안된 접지면 위의 슬릿 모양은 참고문헌 [7]에 있는 안테나의 Archimedean 스파이럴 슬릿 모양을 변형한 것이다. 축비를 개선하기 위해, 접지면 위의 슬릿은 균일한 각도로 나누고 전류가 서로 반대방향인 위치의 도체는 제거되었다. 측정된 반사손실, 방사패턴과 이득은 시뮬레이션 결과와 잘 일치하였다. 비록 접지면 위의 슬릿 구조가 참고문헌 [7]의 슬릿구조와 비교하여 변하였으나, 반사손실, 방사패턴 그리고 이득과 같은 특성은 거의 변하지 않았을 뿐만 아니라 4.88 GHz에서 축비만 현저히 개선되었다.

• 복식
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• 제61권4호
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• pp.38-51
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• 2011

The purpose of this study is to offer data that designers can utilize substantially, by developing creative materials in knit fashion through the analysis relevant to expression characteristics on the mixture in high low class culture, which were shown in knit fashion of contemporary women, as one of methods of pursuing a plan for being able to be appeared creative and unique knit wear. As for a method of this research, studied concept and characteristics on the mixture in high low class culture by preceding researches. And women's knit fashion was selected that is seen to be 3~18 gauge among the world's 4 collections from 2000~2008. The analysis was made with the analytical frame in mixture pattern, and the analytical frame in design element, and item. The results are as follows. The mixture of kidult element and high fashion was shown with characteristic of expressing humor and fun with graffiti, expression like character and cartoon, and fairy-tale fantasy through the exaggerated trifling article. The mixture of grungy element and high fashion was shown with the expression characteristic in the mixture of heterogenous pattern, and in tear, slit without the end treatment due to fraying the end strand in the knit fashion with basic stitch, patch work, fringing and tone-down gray, use of khaki and blue color, and match in opposite color. The mixture of underwear and high fashion was shown the expression characteristic with the emphasis on underwear line like volume up, or with the mixture of details such as pants in diverse lengths, mini skirt, underwear lace, and ribbon.

• The Korean Journal of Physiology and Pharmacology
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• 제25권6호
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• pp.575-583
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• 2021

Composition of the gut microbiota changes with aging and plays an important role in age-associated disease such as metabolic syndrome, cancer, and neurodegeneration. The gut microbiota composition oscillates through the day, and the disruption of their diurnal rhythm results in gut dysbiosis leading to metabolic and immune dysfunctions. It is well documented that circadian rhythm changes with age in several biological functions such as sleep, body temperature, and hormone secretion. However, it is not defined whether the diurnal pattern of gut microbial composition is affected by aging. To evaluate aging effects on the diurnal pattern of the gut microbiome, we evaluated the taxa profiles of cecal contents obtained from young and aged mice of both sexes at daytime and nighttime points by 16S rRNA gene sequencing. At the phylum level, the ratio of Firmicutes to Bacteroidetes and the relative abundances of Verrucomicrobia and Cyanobacteria were increased in aged male mice at night compared with that of young male mice. Meanwhile, the relative abundances of Sutterellaceae, Alloprevotella, Lachnospiraceae UCG-001, and Parasutterella increased in aged female mice at night compared with that of young female mice. The Lachnospiraceae NK4A136 group relative abundance increased in aged mice of both sexes but at opposite time points. These results showed the changes in diurnal patterns of gut microbial composition with aging, which varied depending on the sex of the host. We suggest that disturbed diurnal patterns of the gut microbiome can be a factor for the underlying mechanism of age-associated gut dysbiosis.