• Korea journal of population studies
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• v.24 no.2
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• pp.149-177
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• 2001

This is a study on age-crime curve in Korea. Three data was used in this study as following: First is the crime statistics as aggregated data. Second is the police record(N=3.541 offences) of the male ex-offenders(N=988) who have been released in eleven prisons in 1987 as individual data. Third is the self-reported group-interview data(N=10.198 offences) administered to the male prisoners(N=979) in ten correctional facilities including eight adult prisons, one juvenile prison and one juvenile training center as another individual data. Generally, the right-skewness of age-crime curve has been explained through the difference of crime rate between early starters and late starters. Moffitt explains that this is because of the higher participation rate of the juvenile period of adolescence-limited offenders, but Godttfredson and Hirschi explain that this is because of a similar distribution in the crime rate of both early starters and late starters. the analysis of this study shows that Godttfredson and Hirschi’s explanation on the generality of age-crime-curve distribution is correct, but this can be modified by various factors like a economic crisis. And the peak age of juvenile period is consistent with the Moffitt’s hypothesis that the peak age is contributed to the increase of crime rate of late starters, not with Godttfredson and Hirschi’s one.

• Journal of Dental Rehabilitation and Applied Science
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• v.27 no.1
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• pp.41-50
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• 2011

The gingival zenith is the most apical point of the gingival outline. This study aimed to quantify the mesio-distal and apico-coronal displacements of gingival zenith in maxillary anterior dentition. 50 healthy patients, who ranged in age from 25 to 36 years were recruited for the study. Alginate impressions of the study group were made and poured with the type III stone. The gingival zenith positions of maxillary anterior teeth were measured in a mesial-lateral direction from the vertical bisected midline. The apico-coronal displacements of the gingival zenith of lateral incisors were measured from a line joining the gingival zeniths of the central incisor and canine. The gingival zeniths were distally displaced in 90%, 53% and 23% of the maxillary cetral incisors, lateral incisors and canines respectively. The mean distal displacements of the gingival zeniths to the vertical bisected midline of central incisors, lateral incisors and canines were 0.90 mm, 0.29 mm and 0.06 mm respectively. The gingival zeniths of lateral incisors were positioned $0.73{\pm}0.43$ mm coronally to the line joining the gingival zenith of central incisors and canines. Consideration of these findings may improve restorative procedures in the anterior maxillary dentition.

• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.26 no.4
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• pp.309-316
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• 1990

Age and growth of the Marbled Sole Limanda Yokohamae in Tokyo Bay were studied by otolith reading of 1,070 fishes from May 1986 to April 1988. Examination of the outer margins of the otoliths showed that the hyaline zone as annulus was formed once a year and that its formation was completed at the end of the spawning season (Feb. to Apr.). Growth of the fish was expressed by the von Bertallinffy's equaion as Lt=255.7{1-exp[-0.505(t-0.149)]} for males and Lt=376.9{1-exp[-0.303(t-0.202)]} for females, where Lt is standard length in mm and t is age in years. It was found that the growth of males and females differs, with the females showing a higher growth than the males at each estimated age. Growth in body weight was also examined. Most of the fish examined were found to be not more than three years old, although the oldest fish were four years old for males and seven years old for females.

• Journal of Korean Ophthalmic Optics Society
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• v.19 no.2
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• pp.261-270
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• 2014

Purpose: To study the effect of an artificially induced dioptric blur on acuity and contrast sensitivity using the $Optec^{(R)}$ 6500. Methods: Healthy 31 subjects aged $22.90{\pm}1.92$ (male 16, female 15) who were recruited from university students with 6/6 (20/20) or better corrected visual acuity and normal binocularity. They were measured objective and subjective refraction for full correction and dioptric blur using 0.00 ~ +3.00 D (+0.50 D steps) trial lenses and trial frame. They were measured binocularly visual acuity and contrast sensitivity with the $Optec^{(R)}$ 6500 (Stereo Optical Co., Inc., Chicago, Illinois, USA) under day conditions (photopic condition, $85cd/m^2$). Results: The higher dioptric blur, the less distance visual acuity and decrease rate of visual acuity. The higher dioptric blur, the less contrast sensitivity at all frequencies, and the peak of contrast sensitivity was shifted from middle frequency (6 cpd) to low frequency (1.5 cpd). When the visual acuity was best visual acuity to 0.77, there was the peak point at 6 cpd which was normal contrast sensitivity peak point. Conclusions: If the low refractive error is uncorrected or the refractive error is inappropriate, the contrast sensitivity is decreased and the peak point of contrast sensitivity frequency is shifted abnormally though small uncorrected refractive error. So it will be considered that regular eye test and decision of refractive error correction is important.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.23 no.5
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• pp.385-393
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• 1990

Age and growth in length of anchovy juveniles were analysed from the samples collected from the coastal waters of Chonnam, Korea, in 1988 and 1989. Ages in days were determined by counting growth increments in otolith from 248 individuals. Growth in length versus age in days was well represented by Gompertz curve: $$L =5.76{\times}E xp(1.66 \times(1- E xp(-0.44\;t)))$$, or $$L=3.7{\times}E xp(1.99\times(1-E xp(-0.0614\;t)))$$. The mean growth rate was 0.38 mm/day from 20 days to 40 days. Growth rate was maximum at 10 days, and then decreased gradually. The growth of anchovy juvenile were nearly constant inspite of the sampling dates or stations.

• Journal of Korean Ophthalmic Optics Society
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• v.20 no.3
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• pp.355-362
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• 2015

Purpose: To investigate the effects of the transmittance of diffusive blurson visual acuity and contrast sensitivity. Methods: Visual acuity and contrast sensitivity were measured by using Optec$^{(R)}$ 6500 in Healthy 30 subjects aged $22.83{\pm}0.50$ (male 13, female 17) who were recruited from university students. Cataract simulator was used as a tool for diffusive blur. Visual acuity and contrast sensitivity were measured with varying the transmittance of diffusive blur in order to simulate progression of cataract and concentration in fog. Results: Visual acuity was reduced proportionally with decreasing the transmittance of the diffusive blur as follows: $VA(T)=1.84{\times}10^{-2}T-0.645$. Contrast sensitivity was decreased in all spatial frequencies. Contrast sensitivity in a high spatial frequency band was a greater effect and was off the normal range of contrast sensitivity. The peak of contrast sensitivity was moved in the direction to low frequency. From an intersection point of contrast sensitivity function, we could calculated the transmittance of the diffusive blur being off the normal range and the shift to peak spatial frequency. The peak of contrast sensitivity function was observed to move from 6 to 3 cpd at transmittance of about 78.70%, the contrast sensitivities for all frequencies at transmittance of about 69.71% were deviated from the normal range. Conclusions: The transmittance of diffusive blur causes a reduction in visual acuity and contrast sensitivity, a deviation of normal range of contrast sensitivity, and a shift of peak contrast sensitivity. Therefore the more attention is required when suffering from cataracts or driving in fog.

• Journal of Korean Ophthalmic Optics Society
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• v.19 no.4
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• pp.505-511
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• 2014

Purpose: This study was to investigate the effect of breath alcohol concentration (BrAC) increase with drinking alcohol on contrast sensitivity in the conditions of restricted BrAC. Methods: 23 males in 20s (average age $21.17{\pm}2.19$ years, body mass index (BMI) $22.09{\pm}2.16$) were selected and administered the amount of alcohol to reach 0.05% and 0.08% BrAC calculated by BAC (blood alcohol concentration) Dosing Software program, which was developed as basis of Watson's formula. Then, the contrast sensitivity in various luminance conditions (photopic, mesopic, and mesopic with glare) was measured and compared between these conditions. Results: The contrast sensitivity in all spatial frequency was decreased with BrAC increase. Although BrAC was increased, the peak of contrast sensitivity didn't change as 6 cycle per degree (cpd) in the photopic condition and 3 cpd in the mesopic condition, respectively. But, in the mesopic condition with glare, the peak of contrast sensitivity was shifted from 6 cpd at 0% and 0.05% BrAC to 3 cpd at 0.08% BrAC with increase of alcohol concentration. Conclusions: The increase of BrAC by drinking alcohol induces the decrease of contrast sensitivity in all spatial frequency and the shift of peak of contrast sensitivity, which can cause safety accidents, and may have an effect on various visual tasks.

• Proceedings of the Korea Water Resources Association Conference
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• 2005.05b
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• pp.1249-1253
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• 2005

대부분의 국내 다목적 댐은 유역면적이 넓고 강우기 집중강우로 인하여 유입되는 입자성 물질이 상당히 많은 편이며, 영양염의 증가로 인하여 저수지내부에서 발생되는 입자성 물질도 많다. 이로 인하여 호소에는 외부에서 유입된 무기$\cdot$유기성 입자와 내부 생성된 유기성 물질들이 장기간 축적되어 저수지 용량이 줄어든다. 본 연구에서는 저수지 퇴적물 상태를 탐사하는 효율적인 조사기법을 제시하고자 한다. 퇴적물 탐사기법에는 탄성파탐사 등을 이용하는 간접적인 방법과 코아를 이용하는 직접적인 방법, 퇴적층 동위원소 분석 기법 등이 있으며, 이러한 기법에 대한 기본원리 및 특성, 효용성 등을 평가하고 현장에 적합한 방법을 실제 적용하였다. 퇴적물 분포를 조사하기 위하여 먼저 다중빔(MBES)을 이용한 정밀 지형조사를 실시하였으며 이를 통하여 호저지형의 특징을 간접적으로 평가할 수 있었다. 직접적인 조사방법으로 gravity corer를 사용하여 몇 개의 지점을 sampling하였으며, 잠수부가 직접 핸드코아링를 실시하여 퇴적층을 측정하였다. 16지점에서 실시한Gravity core 결과 세 곳의 조사 정점에서 최대 70cm 두께의 퇴적층이 중력식 시추기에 의해 획득되었으며 다른 정점에서는 50cm, 20cm가 시추되었고 그 나머지 지점에서는 퇴적물이 채취되지 않았다. 이는 퇴적층이 얇아 코아가 쓰러지거나 시료채취가 되지 않은 것으로 판단되었다. 잠수부가 hand corer를 이용한 시료 채취시에 채취된 시료의 퇴적층은 각 지점별로 덕치리 25cm, 경계지점 25cm, 우산리 지점 45cm로 조사되었다. 납-210(반감기 22.3년)을 이용하여 최근에 형성된 주암댐 호수저 퇴적물 중 퇴적작용 이후 교란을 받지 않은 지역의 시추 시료를 대상으로 퇴적속도를 구하였다. 주암호에서 취한 코아퇴적물 시료는 현장에서 냉동하여 실험실에서 약 2cm 간격으로 절단하여 절단체 별로 동위원소 분석을 실시하였다. $^{210}Pb$의 농도는 grand-daughter인 $^{210}Po$를 측정함 후 감마분석에 의하여 구하였다. CF:CS 연령모델을 적용한 결과 깊이에 따른 supported $^{210}Pb$와 퇴적 속도는 0.91cm/year 인 것으로 산정 되었다.

• Clinical and Experimental Pediatrics
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• v.48 no.2
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• pp.154-157
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• 2005

Purpose : We evaluated the epidemiologic and clinical characteristics of mycoplasma pneumonia. Methods : A total of 559 medical records of children with mycoplasma pneumonia admitted to The Catholic University of Korea, Daejeon St. Mary's Hospital, were retrospectively analyzed. Results : The mean annual number of cases was 51. There was a higher occurrence in autumn (September-November, 41.7%) and in winter(26.7%). Outbreaks of mycoplasma pneumonia were noted in 1993-94, 1997, 2001, and 2003. The age distribution showed a peak frequency of 5-6 years of age and 68.2 percent of patients were in 3-8 years of age. The male-to-female ratio was 1.2 : 1. In comparison between 1994 and 2003, there was a difference in age distribution with a peak frequency of 5-6 years of age in 1994, and of 3-4 years of age in 2003. There were outbreaks during autumn and winter in 1993-94, and during summer and autumn in 2003. Conclusion : Outbreaks of mycoplasma pneumonia occurred every 2-4 years in Daejeon in accordance with nationwide epidemics during 1993-2003. The peak incidence of age in the recent outbreak was younger than in the outbreak which occurred 10 years ago, and in outbreaks in Western countries.

• Journal of the Korean Society of Radiology
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• v.14 no.5
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• pp.585-595
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• 2020

Magnetic resonance imaging(MRI) has become an important technique for examining changes in human brain structure with neurological disorders. Brain development is a very complex process, and is affected by neurogenesiss and genetic programs. As age increases, structures of the brain change, which can contribute to the formation of brain diseases. Among the various factors, Gender is one of the greatest influential factors that affect the development of a healthy brain. The images were analyzed through various programs found in FSL such as SIENAX, FIRST, and Vertex analysis. Our results show that significant gender-related differences in subcortical areas were observed at the particular age group. The magnitude of these differences between gender and volume varied depending on the area investigated. In this study, we used more advanced 3T MRI for the structural analysis of subcortical structures between each gender. In addition, Vertex Analysis was used to visualize the volumetric differences in subcortical structures between each gender. This study is limited to groups in their 70s, therefore, further studies are needed for wider age groups.