• 한국통신학회논문지
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• 제22권11호
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• pp.2531-2542
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• 1997

This paper describes a method for region segmentation and string extractionin documents which are mixed with text, graphic and picture images by the use of the structural characteristic of connceted components. In segmentation of non-text regionas, with connection-characteristic functions which are made by structural characteristic of connected components, segmentation process is progressed. In the string extraction, first we organize basic-unit-region of which vertical and horizontal length are 1/4 of average length of connection components. Second, by merging the basic-unit-regions one other that have smaller values than a given connection intensity threshold. Third, by linking the word blocks with similar block anagles, initial strings are cresed. Finally the whold strings are generated by merging remaining word blocks whose angles are not decided, if their height and prosition are similar to the initial strings. This method can extract strings that are neither horizontal nor of various character sizes. Through computer exteriments with different style documents, we have shown that the feasibility of our method successes.

• 한국의류산업학회지
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• 제7권4호
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• pp.419-425
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• 2005

The purpose of this study is to analyze the physical characteristic by directly measuring the wheelchair using disabled women. The subjects were 103 disabled women of wheelchair used women and between 20 - 55 years of age. The result of this study is as follow. There was a remarkable difference in the physical characteristic of wheelchair using disabled women due to their cause of disability. The cause of disability was classified into the 4 groups; poliomyelitis, spiral cord injury, muscular dystrophy, cerebral palsy. Poliomyelitis disability generally had a large horizontal area due to their strong upper body. People with spiral cord injury disability was shown to have the largest height, cervical height, waist back length, crotch length, knee length, The group of muscular dystrophy disabled people have the shortest length of body and also lean. The cebral palsy group of disabled people has an average length and height size body. A comparison of anthropometric measurements of wheelchair using disabled women with National Anthropometric Survey Korea(1997) was significant difference. People with poliomyelitis disability was shown to have a larger waist back length, neck point to breast point compared to normal women, but stature, crotch length was shorter compared to normal women. People with spiral cord injury disability had a similar in the vertical area. The group of muscular dystrophy and cebral palsy disabled people was short and smaller in general compared to a normal woman.

• 한국자동차공학회논문집
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• 제24권2호
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• pp.205-213
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• 2016

Heat loss and fin efficiency of symmetric and asymmetric trapezoidal fins with variable slope of fin's top surface are obtained by using a two-dimensional analytic method. Shapes of symmetric and asymmetric fins are changed from rectangular through trapezoidal to triangular by adjusting the fin shape factor. The ratio of symmetric trapezoidal fin length to asymmetric trapezoidal fin length is presented as a function of fin base height and convection characteristic number. The ratio of symmetric trapezoidal fin efficiency to asymmetric trapezoidal fin efficiency is presented as a function of the fin base height and fin shape factor. One of results shows that asymmetric trapezoidal fin length is shorter than symmetric trapezoidal fin length (i.e., asymmetric trapezoidal fin volume is smaller than symmetric trapezoidal fin volume) for the same heat loss when the fin base height and fin shape factor are the same.

• Journal of the Korean Wood Science and Technology
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• 제26권2호
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• pp.16-23
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• 1998

This paper examines the effects of specimen length and grade on the strength and stiffness properties of structural timber of radiata pine. The tensile strength and modulus of elasticity of 1,902 machine-graded boards with 3.15- and 1.62-m clear span lengths, were determined using a horizontal tension test machine. The mean failure and characteristic stress values for tensile strength show an extremely high dependency on test specimen length. The mean and characteristic values of both modulus of elasticity and tensile strength show significant dependency on machine stress grades.

• Journal of the Korean Society for Industrial and Applied Mathematics
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• 제12권1호
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• pp.25-32
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• 2008

A pin fin is optimized based on the increasing rate of heat loss by using a two-dimensional analytic method. The optimum heat loss, corresponding optimum thermal resistance and fin length are presented as a function of the fin base thickness, convection characteristic numbers ratio, fin outer radius and ambient convection characteristic number. One of the results shows that both the optimum heat loss and fin length decrease linearly whereas the optimum thermal resistance increases very slightly with increase of the fin base thickness.

• 한국해양공학회지
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• 제18권6호
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• pp.22-28
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• 2004

A mathematical model has been developed to evaluate the capability of sea water exchanges under tidal and diffusive environments and has been verified through comparison with numerical experiments. From the mathematical analysis, this study presents the rates of sea water exchanges due to the tidal inflow and diffusion process. The port characteristic length $L_p$ is the most significant evaluation index.

• 한국농공학회지
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• 제30권4호
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• pp.45-61
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• 1988

The purpose of this study is to develop regression equations between annual specific sedi- ment of reservoirs and physiographic factors of watersheds. 122 irrigation reservoirs, which have irrigation areas equal to or larger than 200 ha, located in Korea except Cheju province are used in the analysis. Simple regression analyses between the specific annual sediment and each of the physical characteristic factors of the reservoirs are carried out at first. Then, multiple regression analyses between the annual specific sediment and the physical characteristic factors with high correlation coefficients in the simple regression analyses are made. The results obtained from this study are as follows : 1. The results of the sirnple regression analyses show that in each province the watershed area, the length of mainstream, the circumferential length of watershed have high cor- relation coefficients (R=0.814-0.986), and that drainage density, reservoir capacity per watershed area, drainage frequency, basin relief have low correlation coefficients (R=0. 387-0.955). 2. The purposed multiple regression equations between the annual specific sediment of reservoirs and three major characteritic factors of watersheds, namely, the watershed area, the circumferential length of watershed, and the length of mainstream, are proposed as given in Table 2. 3. The result of the simple regression analyses with respect to the reservoir elevation except Jeonnam province, which has very different characteristics comparing to other provinces, shows that watershed area, main stream length and circumferential length have high correlation coefficients (R=0.806-0.884) in low-elevation reservoirs and intermediate- elevation reservoirs, but low correlation coefficients (R=0.639-0.739) in high-elevation reservoirs. 4. With respect to the reservoir elevation, the proposed multiple regression equations bet- ween the annual specific sediment of reservoirs and the three major characteristic factors of watershed which have high correlation coefficients are proposed as given in Table 5.

• 한국병원경영학회지
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• 제21권4호
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• pp.45-54
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• 2016

The purpose of this study is to identify patient and hospital characteristics with pulmonary tuberculosis and to analyze factors which were influencing length of stay and treatment. The Korean National Hospital Discharge In-depth Injury Survey database from 2006 to 2012 was used for analysis. Study subjects were 4,704 patients and analyzed by using frequency, chi-square and logistic regression through using STATA 12.0. To avoid selection bias, we used propensity score matching. Analysis results show that the length of stay and treatment of pulmonary tuberculosis was different between insurance types. Patients characteristic(female, comorbidity, admission by outpatient department, medical insurance type) and hospital characteristic(500-999 beds, over 1000 beds) significantly influence length of stay. Admission by outpatient department and over 1000 beds are significantly influence treatment. Based on these findings, it is necessary to clarify between length of stay and treatment outcome by medical aids beneficiaries and audit hospitals follow discharge guidelines in pulmonary tuberculosis patients.

• Composites Research
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• 제24권4호
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• pp.29-35
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• 2011

전통적인 특성길이 방법을 이용하여 원공이 있는 복합재 적층판의 강도를 예측하기 위해서는 원공이 있는 적층뿐만 아니라 원공이 없는 적층판에 대한 시험 결과와 유한요소해석이 필요하였다. 본 논문에서는 응력집중계수와 재료상수를 이용하여 유한요소해석 없이 복합재 적층판 원공 주위의 응력분포 및 인장특성길이를 추정하고, 이를 바탕으로 원공이 있는 복합재 적층판의 인장강도를 예측할 수 있는 방법을 제안하였다. 또한 새로운 방법에서는 재료의 효과가 변수로 고려되므로 다양한 재료에 대한 적용이 가능하며 원공이 있는 복합재 적층판에 대한 시험도 생략할 수 있다. 적층판 주위의 응력분포는 유한요소해석과의 비교를 통해 검증하였고, 최종적으로는 USN125 탄소/에폭시 적층판을 제작하여 파손하중 예측 결과와 시험 결과를 비교하였다. 원공이 있는 다양한 형상의 복합재 적층판의 파손강도 예측 결과는 최대 8% 이내의 오차로 시험 결과와 잘 일치함을 확인하였다.

• 한국항공우주학회지
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• 제49권7호
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• pp.549-555
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• 2021

원공이 있는 복합재 적층판의 강도는 복합재 항공기기 설계 시 충격하중이 가해지는 부위의 설계 허용치로 사용된다. 일반적으로 BVID (Barely Visible Impact Damage)에 의한 강도저하는 24.0 mm 폭의 시편에 6.0 mm 지름의 원공이 있는 시편의 강도로 가정한다. 본 연구에서는 원공이 있는 복합재 적층판의 강도에 적층각이 미치는 영향을 조사하기 위해 잔류강도 시험을 수행하였다. 원공이 있는 적층판의 강도를 예측하기 위해 특성길이를 이용한 점응력 파손기준을 사용하였고, 이론해를 검증하기 위하여 유한요소해석을 수행하였다. 실험결과로부터 특성길이는 0°, ±45°와 90°층의 비율과 관련이 있음을 보였다. 또한 회귀분석을 통하여 임의의 적층 패턴에 대한 특성길이와 원공이 없는 시편의 강도를 결정하였다.