• 대한조선학회논문집
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• 제29권3호
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• pp.125-130
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• 1992

실제 해상에서 운항중인 선박의 6자유도 운동 및 해상의 파도를 계측할 수 있는 시스템을 개발하였다. 이 시스템은 Miles의 방법에 따라 7개의 가속도계로 선체의 운동을 계측하고, 초음파 파고계를 이용하여 선수부에서의 상대운동을 계측하여 상대운동에서 선체운동을 소거함으로써 해상에서의 파랑에 관한 정보(파고 및 주기)를 해석할 수 있다. 모형시험을 수행하여 개발된 시스템의 우수성을 확인하였으며, 원격조종 모형시험시 운동계측기로의 적용가능성도 발견하였다.

• 한국항해학회지
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• 제19권1호
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• pp.9-16
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• 1995

We are confronted with the serious EMI(electromagnetic interference) problems in company with the development of electronic equipments. Accordingly it is also required to construct some anechoic chambers for EMI measurement. Furthermore it is very important to evaluate the chamber characteristics in advance of its construction. For that purpose we have analyzed the characteristics by computer simulation in base on the image method, and compared the results with the measured ones. In case of 3-meter method as a result, the curved line of height pattern of open site varies similarly as that of height pattern of anechoic chamber. When we measure the electromagnetic strength and can get the height pattern curves by frequencies, we utilized it effectively because we can protect instrumental errors in measurement. On the other hand, there is a little difference in site attenuation above 700MHz. When the ferrite grid was used however, the calculated values agree well with the measured values up to 1000MHz with the exception of 30-40 MHz range. The reason is that we don't consider the antenna coupling in the low frequencies of 30-100MHz range.

• 한국측량학회지
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• 제28권4호
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• pp.441-448
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• 2010

본 논문은 계절별로 획득된 항공라이다 자료로부터 수고를 추정하여 수관울폐도와 자료융합에 따른 영향을 분석하였다. 수고추정은 수목에서 반사되는 신호(First Return : FR)와 지표에서 반사되는 신호(Last Return : LR)를 추출하고, 영상분할을 통해 수목개체를 가정하여 개체목별 수고를 획득하는 방법을 적용하였다. 계절별 자료를 통해 획득한 각 수고 자료와 융합자료로부터 획득한 수고의 결과를 비교하였으며, 수고측정기를 사용하여 현지 측정을 하여 정확성을 비교하고, 항공라이다를 통해 획득한 자료들을 융합한 결과에 대한 그 활용성을 검토하였다. 실험 결과, 수목개체를 위한 영상분할 결과는 0.5미터 점군간격보다 1미터 간격이 현지조사 결과와 가까웠으며, 수목고의 경우 각 계절별 자료보다 융합자료를 활용한 결과가 현지 측정 결과에 접근하고 있음을 알 수 있었다.

• 한국화재소방학회논문지
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• 제23권6호
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• pp.10-15
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• 2009

산불에서의 화염높이 산정은 복사열전달에 의한 수평 또는 수직적 화염확산을 예측하는데 있어 매우 중요한 부분이다. 화염특성 중 화염높이는 빛을 수반하는 화염(the luminous flame)의 평균높이로 확인할 수 있다. 본 연구에서는 외부 풍속과 경사 등으로 인한 화염 높이가 변화될 수 있는 조건을 제외한 산림내 지표연소물질(surface fuel)인 소나무 낙엽층(fuel bed)에 대한 화염높이 관측실험과 열량분석계을 이용하여 발열량(Heat Release Rate) 측정실험과 수치해석을 통해 지표연소물질에 대한 화염높이 산출식 $H_f=0.027(\dot{Q'})^{2/3}$을 도출하였다. 실험값과 개발 산정식, 기존 Heskestad 식과의 적용값 비교 결과, 소나무 낙엽의 경우, 실험값과 개발 산정식 적용값의 표준오차는 0.08, 실험값과 기존 Heskestad 식의 표준오차는 0.23으로 개발 산정식의 정확성이 높은 것으로 나타났다.

• 복식
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• 제53권4호
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• pp.87-99
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• 2003

The measurement in ruling period of King Sejong in Chosun Dynasty remained unchanged compared with that of Goyeo Dynasty. But Hwangjongchuck, the basis of measurement was amended in the 7th year in ruling period of King Sejong, Juchuck, Youngchochuck, Cholegichuck in the 12th, and Pobeckchuck in the 13th. The record of Pobeckchuck first appeared in the true record of Chosun Dynasty in the 4th year in ruling period of Sejong, and first record on the amendment of the Pobeckchuck was found in the 13th year in his ruling period. The presentation of the comparison of Pobeckchuck with Cholegichuck in volume 128 of true record of Sejong makes help the estimation of the length of Pobeckchuck. To calculate one Chuck of Pobeckchuck with this measurement comes to 44.75cm in present measurement, and the length at this time had remained unchanged to Yeonsangun period. Important fact which was newly found in the true record of Chosun Dynasty was that Pobeckchuck had been used for diverse purposes. Pobeckchuck was used to measure width, length and thickness in manufacturing wardrobe. and also to measure cloth decorating wardrobe. This is the first record(4th year of reign of Sejong) showing that Pobeckchuck was first used to measure cloth in Chosun Dynasty The record shows that Pobeckchuck was also used to measure the length of circumference of castle for its construction. to measure distances between people, the length of hook of wooden handle, and the height of man.

• 한국광학회지
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• 제20권2호
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• pp.81-86
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• 2009

디지털 홀로그램과 굴절률 차이를 이용하여 사용된 광원의 파장보다 큰 단차를 측정하는 연구를 하였다. 위상차를 측정하여 단차를 측정하는 방식에서는 위상차가 $2{\pi}$보다 큰 경우에는 원리상 단차를 구하기 어렵다. 이를 보완하기 위하여 굴절률 차이를 이용하여 인위적으로 광경로차를 줄여 파장보다 큰 단차를 측정할 수 있는 디지털 홀로그래피 시스템을 구성하였고, 실험적으로 파장의 약 3배 이상의 단차를 측정하였다.

• 한국의류학회지
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• 제28권11호
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• pp.1524-1535
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• 2004

The purpose of this study was to develop middle school girl's' school uniform sizing system according to their body types. The data collected with anthropometric measurements from 390 middle school girls aged 12-15 years old was analyzed using t-test, ANOVA, factor analysis and cluster analysis. A new sizing system was developed in accordance with each of the 2 body-type clusters. The analysis of two-way distribution of 'height-bust girth' and 'height-waist girth' was conducted for the girls of the first grade, which is the time when they purchase their school uniforms. The interval of sizing system was defined in consideration with the most efficient distribution of the body sizes utilizing Loss Function. This study also provided Reference-Sizes and Growth-Allowance Measures for each sizing system to help pattern drafting and clothing construction of the uniform manufacturers. The cover ratio of sizing system proposed by this study was higher when compared with that of the National Agency for Technology and Quality and uniform manufacturing companies, Thus, the result of this study is expected to make up the current sizing system of the school uniform.

• 한국정밀공학회지
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• 제22권11호
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• pp.64-71
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• 2005

In order to measure surface roughness profile, stylus type equipments are commonly used, but the stylus keeps contact with surface and damages specimens by its tip pressure. Therefore, optics based measurement systems are developed, and light phase interferometer, which is based on light interference phenomenon, is the most noticeable research. However, light interference based measurements require translation mechanisms of nano-meter order in order to generate phase differences or multiple focusing, thus the systems cannot satisfy the industrial need of on-the-machine and in-process measurement to achieve factory automation and productive enhancement. In this research, we focused light reflectance phenomenon rather than the light interference, because reflectance based method do not need translation mechanisms. However, the method cannot direct]y measure surface roughness profile, because reflected light consists of several components and thus it cannot supply surface height information with its original form. In order to overcome the demerit, we newly proposed an image processing based algorithm, which can separate reflected light components and conduct parameterization and reconstruction process with respect to surface height information, and then confirmed the reliability of proposed algorithm by experiment.

• 한국공간구조학회논문집
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• 제14권2호
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• pp.51-58
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• 2014

Meteorological observatories use measuring boards on even ground in open areas to measure the amount of snowfall. However, it is very difficult to evaluate the accurate amount of snowfall because of the effects of the wind. Therefore, this study tried to determine the internal wind flow inside a windbreak fence to identify an area that was not affected by wind in order to measure the snowfall. We performed a computational fluid dynamics analysis, wind tunnel test of the type and height of the windbreak fence, and analyzed the wind flow inside the fence. The results showed that a double windbreak fence was better than a single windbreak fence for reducing the wind velocity. The reduction of the wind velocity was highest in the middle of a windbreak fence with a width of 4 m and a height of 60cm, where the windbreak fences were fixed to the ground.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2003년도 춘계학술대회 논문집 센서 박막재료 반도체 세라믹
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• pp.120-123
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• 2003

To investigate the characteristics of the single dendrimer molecule, we attempt to measure morphology and electrical properties of the self-assembled dendrimer on Au (111)substrate with SPM(scanning probe microscopy). The same self-assembly procedure was used for two different concentrations, $10{\mu}mol/ml$ and $100{\mu}mol/ml$. The case of lower concentration, we can measure the diameter and the height of the single molecule with the tapping mode AFM image. The imaged single molecules were dome shaped and the average diameter and height were 15.6 nm, 1.2 nm respectively. From these sizes, we can calculate the volume of the single molecule. The volume of the single molecule was estimated about $116nm^3$. However, that of higher concentration, it is difficult to obtain obvious image of the single molecule. To add to, I-V characteristics were investigated using STM, on which the phenomenon of negative differential resistance (NDR)was observed between 0.14 V and 0.24 V reproductively.