• The Journal of The Korea Institute of Intelligent Transport Systems
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• v.23 no.2
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• pp.106-118
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• 2024

Interest in personal mobility has increased with the growing significance of first-mile and last-mile connectivity in smart mobility services. This study aims to propose a methodology for setting the service area of free-floating personal mobility sharing services and determining the optimal fleet size for the selected shared service area to address first-mile and last-mile challenges. We utilize population data, smart card data, and building data. Additionally, we estimate latent demand by incorporating age-specific and distance-specific utilization rates based on personal mobility device data. Along with the latent demand, we determine the service area based on locations of transit stops and buildings. We apply the proposed methodology to Yeongjong Island, Incheon. As a result, dense residential areas and popular beachside locations are designated as personal mobility sharing service areas. The fleet size for personal mobility in the dense residential service area is determined to be 1,022 units, while the fleet size for the beachside service area is set at 269 units.

• Clinical and Experimental Pediatrics
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• v.46 no.11
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• pp.1095-1100
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• 2003

Purpose : Children with acute colonic diverticulitis(ACD), can be misdiagnosed with acute appendicitis. Methods : We reviewed 15 cases of ACD during five years, from January 1998 to June 2002 retrospectively. Results : Most patients(80%) with ACD in children presented with right lower quadrant pain. The primary diagnosis on admission was mostly acute appendicitis(87%), and all ACD in children occurred in the right colon. Fourteen patients were managed by conservative treatment including antibiotics. A follow-up study was performed in 15 patients. There were symptomatic recurrences in two patients, but no significant complication was noted. The frequency of ACD was 11.7 per 1000 acute appendicitis. Conclusion : ACD in children can mostly be cured by conservative treatment. It is prudent to choose the management through the diagnostic work up, including abdominal sonography and computed tomography, because there was no significant difference of clinical findings between ACD and acute appendicitis.

• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.37 no.2
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• pp.106-116
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• 2001

A serious of studies on the fishing gear and system of the East Sea trawl fishery was carried out to improve the fishing efficiency and the working conditions. As the first step of these studies, the fishing gear and system of the traditional East Sea trawl were checked in order to solve the some problems, such as the poor sheering efficiency of net mouth, the inconvenient fishing system of the side trawl and etc. And then the fishing system was reorganized from the side trawl into the stern trawl by setting up the net drum system on the stern deck, and introduction of two types of new designed nets, one for mainly the midwater trawl and the other for the bottom trawl. The results of the field experiment on the modified system and nets can be summarized as follows : 1. the modified system was well worked and could save the man-labour by about 80%. 2. The sheering efficiency of the improved net, A type was improved to 20 m height and 30 m width in the net mouth, and that of B type net, to 10 m height and 33 m width, compared with 1.5 m height and 15 m width in the traditional net. 3. Catch efficiency of pink shrimp in A or B type net was better about 3 or 5 times than that of traditional net, and in B net, for herring and other bottom fishes is better about 2 times than that of the traditional net.

• Nuclear Medicine and Molecular Imaging
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• v.42 no.6
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• pp.469-477
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• 2008

Purpose: The goal of this paper is to present the design and performance of a position encoding circuit for $16{\times}16$ array of position sensitive multi-anode photomultiplier tube for small animal PET scanners. This circuit which reduces the number of readout channels from 256 to 4 channels is based on a charge division method utilizing a resistor array. Materials and Methods: The position encoding circuit was simulated with PSpice before fabrication. The position encoding circuit reads out the signals from H9500 flat panel PMTs (Hamamatsu Photonics K.K., Japan) on which $1.5{\times}1.5{\times}7.0\;mm^3$ $L_{0.9}GSO$ ($Lu_{1.8}Gd_{0.2}SiO_{5}:Ce$) crystals were mounted. For coincidence detection, two different PET modules were used. One PET module consisted of a $29{\times}29\;L_{0.9}GSO$ crystal layer, and the other PET module two $28{\times}28$ and $29{\times}29\;L_{0.9}GSO$ crystal layers which have relative offsets by half a crystal pitch in x- and y-directions. The crystal mapping algorithm was also developed to identify crystals. Results: Each crystal was clearly visible in flood images. The crystal identification capability was enhanced further by changing the values of resistors near the edge of the resistor array. Energy resolutions of individual crystal were about 11.6%(SD 1.6). The flood images were segmented well with the proposed crystal mapping algorithm. Conclusion: The position encoding circuit resulted in a clear separation of crystals and sufficient energy resolutions with H9500 flat-panel PMT and $L_{0.9}GSO$ crystals. This circuit is good enough for use in small animal PET scanners.

• Journal of Sericultural and Entomological Science
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• no.11
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• pp.51-54
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• 1970

External features of silkworms are not evident during stage of larvae and pupae like in the stage of imagines. In general, therefore, sexing of larvae has been depended on Herold's gland of males or Ishiwata' sexual spots (Anterior sexual spots and posterior sexual spots) of a female 2-3 days after of the 5th age since it is relatively easy to classify in this period. Sometimes. however, we made mistake of sexing since a pair of small spot around the abdomen of 9th abdominal of males and posterior sexual spot of females was found at the same position. This study has been conducted in order to obtain essential points of classifing the above it will be summarized as follows: A. Existence of the males small spots on 9th abdominal segment were varied by races. Through observation races by races the more larvae which had the small spots were found in chinese races than the Japanese, and 57 percent of the Chinese orgin larvae of the small spot were picked among total counted males. B. The small spots were more or less roundly shaped just as posterior sexual spots of females, and these spots were colored slightly even the colors were somewhat different by races. Milky color was seen in the case of the posterior sexual spots. The small spots were observed smaller than the posterior sexual spots. It is difficult classify the sexual spots during stage of mature larvae, but it was easily classified small spots by the naked eye even in the same stage. The small spots were found at the same site of the posterior sexual spots. C. After sexing by based on the small spots and Herold's gland, the sexing through purpae bodies were carried out again to confirm its correctness. Average 5. 2 percent of more opposite sex were found in the latter. This figures supposed to be caused the location of the small spots coincide with the posterior sexual spots. D. The moths, no disorder were found in daily activities and their generative functions depend on the existence of the small spot and thickness of its color. E. It is presumed that existence of the small spots were caused by races, heredity nature, voltinism, moulting, and etc.

• Journal of the Institute of Electronics Engineers of Korea SP
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• v.46 no.3
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• pp.96-104
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• 2009

In this paper, we propose a no-reference objective Quality assessment metrics of image. The blockiness and blurring of edge areas which are sensitive to the human visual system are modeled as step functions. Blocking and blur metrics are obtained by estimating local visibility of blockiness and edge width, For the blocking metric, horizontal and vertical blocking lines are first determined by accumulating weighted differences of adjacent pixels and then the local visibility of blockiness at the intersection of blocking lines is obtained from the total difference of amplitudes of the 2-D step function which is modelled as a blocking region. The blurred input image is first re-blurred by a Gaussian blur kernel and an edge mask image is generated. In edge blocks, the local edge width is calculated from four directional projections (horizontal, vertical and two diagonal directions) using local extrema positions. In addition, the kurtosis and SSIM are used to compute the blur metric. The final no-reference objective metric is computed after those values are combined using an appropriate function. Experimental results show that the proposed objective metrics are highly correlated to the subjective data.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.31 no.6B
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• pp.531-539
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• 2011

It has been widely acknowledged that climate system associated with extreme rainfall events was difficult to understand and extreme rainfall simulation in climate model was more difficult. This study developed a new model for extracting rainfall filed associated with extreme events as a way to characterize large scale climate system. Main interests are to derive location, size and direction of the rainfall field and this study developed an algorithm to extract the above characteristics from global climate data set. This study mainly utilized specific humidity and wind vectors driven by NCEP reanalysis data to define the rainfall field. Geometric first and second moments have been extensively employed in defining the rainfall field in selected zone, and an ellipsoid based model were finally introduced. The proposed geometric moments based ellipsoid model works equally well with regularly and irregularly distributed synthetic grid data. Finally, the proposed model was applied to space-time real rainfall filed. It was found that location, size and direction of the rainfall field was successfully extracted.

• Proceedings of the Korean Quaternary Association Conference
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• 2004.06a
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• pp.49-50
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• 2004

푸른 진주라 불리는 훕스굴호는 러시아 국경에 인접한 몽고 북부의 청정호수로 해발 약 1,645m 지점에 위치한다. 훕스굴호의 길이는 약 136km이고, 폭은 20-40km이며, 최대수심은 약 262m 이다. 이 호수의 물은 세계에서 가장 깨끗한 담수 중 하나로 몽고 지표수원의 약 70%를 공급하고 있다. 훕스굴호는 바이칼 열곡대내에 형성된 일종의 구조호로 약 240만년 내지 400만년전에 형성된 것으로 추정되고 있다. 훕스굴호는 자연공원으로 지정되어 보호되고 있으며, 따라서 호수의 유역은 다행스럽게도 인간활동에 오염되거나 교란되지 않아 다양하고 흥미로운 육상/수성 생물상을 보유하고 있으며, 퇴적물 기록 역시 후기 신생대 동안의 중앙아시아의 지구환경 및 기후변화 연구에 매우 적합하다. 바이칼 시추사업 (Baikal Drilling Project)은 신생대 후기 동안의 중앙아시아의 지구조진화 및 전지구적 기후변화를 규명하기 위해 미국, 러시아, 일본, 독일 등이 참여한 다국가 공동사업이다. 바이칼 시추사업 연구팀은 지난 15년간 많은 노력과 예산을 투자하여 바이칼 호로부터 총 1,600m에 이르는 방대한 양의 퇴적물 코아를 성공적으로 회수하였고, 이 시료를 이용하여 후기 신생대 동안의 중부 유라시아 대륙의 고기후/고환경 진화과정을 성공적으로 규명하였다. 바이칼 시추사업이 성공적으로 진행됨에 따라, 이 사업에 참여했던 러시아와 일본의 과학자들은 바이칼호의 서쪽에 위치한 몽고 북부의 훕스굴에도 많은 관심을 가지게 되었으며, 동시에 바이칼 시추사업의 후속사업으로 훕스굴 시추사업을 새롭게 추진하게 되었다. 한편, 대륙내부에서의 제4기 지구환경 및 기후 변화 과정에 많은 관심을 가지고 연구해 오던 한국지질자원연구원도 2003년에 정식 회원으로 훕스굴 시추사업에 합류하였다. 훕스굴 시추사업 연구팀은 몽고의 지질광물자원연구소 (대표연구기관), 러시아의 지구화학연구소, 일본의 나고야대학교 그리고 한국의 지질자원연구원 등 4개국의 연구기관으로 구성되어 있다. 이들 4개 연구기관은 시추획득 및 기초연구 수행에 필요한 연구비를 현금 혹은 현물 (장비 포함)의 형태로 공동부담하고 있으며, 따라서 획득한 시추코아에 대해서도 각 연구기관이 전 구간에 대해 동일하게 25%의 소유권을 가지고 있다. 훕스굴 시추사업은 2008년까지 수행될 계획이며, 시추작업은 2005년까지 완료될 계획이다. 연구 진행과 관련하여, 공동연구의 명분을 높이고 분석의 효율성을 높이기 위해서 시료채취 및 기초자료 획득은 4개국의 연구원이 모여 공동으로 수행한 후의 결과물을 서로 공유하고, 자세한 전문분야 연구는 각 국의 대표기관이 독립적으로 수행하는 방식을 택하였다. 훕스굴에 대한 제1차 시추작업은 2004년 3월 말에 실시하였다. 시추작업 결과, 약 80m의 시추 코아가 성공적으로 회수되어 현재 러시아 이르쿠츠크 지구화학연구소에 보관중이다. 이 시추코아는 2004년 8월 중순경에 4개국 연구팀원들에 의해 공동으로 기재된 후에 분할될 계획이다. 분할된 시료는 국내로 운반되어 다양한 전문분야별 연구에 이용될 것이다. 한편, 제2차 시추작업은 2004년 12월에서 2005년 2월 사이에 실시될 계획이다. 수백만년에 이르는 장기간에 걸쳐 지구환경변화 기록이 보존되어 있는 훕스굴호에 대한 시추사업은 후기 신생대 동안 유라시아 대륙 중부에서 일어난 지구환경 및 기후변화를 이해함과 동시에 이러한 변화가 육상생태계 및 지표지질환경에 미친 영향을 이해하는데 크게 기여할 것이다.

• The korean journal of orthodontics
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• v.29 no.3 s.74
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• pp.339-347
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• 1999

The purpose of this study was to investigate the variations of the skeletal and dentoalveolar dimensions in relation to vertical facial patterns. Lateral cephalogram of 200 cases (100 cases of male and 100 cases of female, average age of which was 23.2 years) were traced and some measurements of skeletal and dentoalveolar dimensions were measured. The ratio of UAFH/LAFH was employed to classify the samples into groups of excess and short lower anterior facial height. And the comparison between two groups were taken statistacally. The following results were obtained. 1. The dentoalveolar height, lower anterior facial height, lower genial angle, and FMA in the excess-lower-anterior-facial-height group were significantly larger than those in short-lower-anterior-facial-height group. 2. The dentoalveolar height, facial height, ramus height, and Jarabak ratio in the male subjects were significantly larger than those in the female subjects. 3. The UAFH/LAFH ratio showed a significant correlation to upper, lower facial height, AUDH, PUDH, ALDH, PLDH, Lower gonial angle, FMA, and $Bj\"{o}rk's$ Sum.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.30 no.4
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• pp.398-404
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• 1985

This study was conducted to define the seasonal differences in the morphological characteristics, the photosynthetic abilities and the dark respirations of the 4-year old ginseng leaves. Chlorophyll-a content in the ginseng leaf was significantly decreased at September than at June but content of chlorophyll-b was not showed seasonal difference. At June, the amounts of chlorophyll a and b in the ginseng leaves grown in the back row were rather abundant than those grown in the front row, but no significant differencies were detected between rows at September. The estimated optimum light intensity for the photosynthesis of ginseng leaves was higher at June than at September and higher in the front row than the back row but was significantly decreased by air temperature above 25$^{\circ}C$. The light compensation point was elevated in higher temperature and at September than June. The amount of photosynthesis was significantly increased in the ginseng plant grown in the front row than the back row at June but the reverse was significant at September. The highest photosynthesis was observed in temperature range of 20 - 25$^{\circ}C$ at June and range of 15 -20$^{\circ}C$ at September. The optimum temperature range of photosynthesis was 21$^{\circ}C$ to 25$^{\circ}C$ at June and 14$^{\circ}C$ to 21$^{\circ}C$ at September, and that was higher in the back row than the front row. High temperature significantly stimulated the dark respiration of ginseng leaves and the respiratory quotients(Q$\_$10/) of the ginseng leaves showed a significant seasonal variation.