• Communications for Statistical Applications and Methods
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• v.16 no.1
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• pp.85-102
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• 2009

This paper derives conversion formulas from yearly-based absolute rates of decrements to monthly-based rates of decrement due to cause J under fractional age distributions. Next, it suggests conversion formulas from monthly-based absolute rates of decrements to monthly-based rates of decrement due to cause j under fractional age distributions. In addition, it applies the conversion formulas including a dynamic lapse rate model to variable annuities. Some numerical examples are discussed.

• The Korean Journal of Applied Statistics
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• v.29 no.5
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• pp.987-998
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• 2016

Auto insurance is an insurance product that requires the proper application of pricing techniques due to intense market competition and the rate regulations of financial authorities. Especially, population change according to aging and rating faction segmentation mainly affect the pricing process. This study suggests a pricing optimization methodology through the proper estimation of age factors. To properly estimate the future distribution of age factor, age change, renewal and conversion of customers are considered as main effects for the optimization of estimation and application. The properness and effectiveness for the suggested method will be proved by a comparison of results applied (one for current distribution and the other for future distribution) at the off-balance process. This study suggests an appropriate risk estimation methodology based on optimization that uses the proper estimation of future distribution to protect from the over or under estimation of risk.

• The Korean Journal of Applied Statistics
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• v.21 no.6
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• pp.933-945
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• 2008

The genetic association test on age of onset trait aims to detect the putative gene by means of linear rank tests for a significant trend of onset distributions with genotypes. However, due to the selective sampling of recruiting subjects with ages less than a pre-specified limit, the genotype groups are subject to substantially different censored distributions and thus this is one reason for the low efficiencies in the linear rank tests. In testing the equality of two survival distributions, log-rank statistic is preferred to the Wilcoxon statistic, when censored observations are nonignorable. Therefore, for more then two groups, we propose a generalized log-rank test for trend as a genetic association test. Monte Carlo studies are conducted to investigate the performances of the test statistics examined in this paper.

• Economic and Environmental Geology
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• v.52 no.1
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• pp.49-64
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• 2019

SHRIMP U-Pb ages were analyzed for the detrital zircons separated from the Jangsan Formation of the Lower Paleozoic Joseon Supergroup in the Taebaeksan Basin and the Mungyeong area. Similar to the previously reported from Taebaeksan basin, the detrital zircons show strong peaks near the age of about 1.8-2.0 Ga and about 2.5 Ga. This indicates that the detrital zircons of the Jangsan Formation originated from the basement rocks of the Korean Peninsula. Although the age of the basement rocks on the Korean Peninsula is mainly concentrated in the 1.8-2.0 Ga, the age of about 2.5 Ga is clearly visible in the Jangsan Formation, suggesting that the age distribution of the basement rocks exposed to the surface at that time may be somewhat different from now. The detrital zircons of age-unknown Geumsusan Formation distributed between Danyang and Jecheon also show the U-Pb age distribution with a strong peaks around 1.8-2.0 Ga and 2.5 Ga, which is very similar to that of the Jangsan Formation, suggesting a possibility that the two formations are likely to be correlated.

• Proceedings of the Costume Culture Conference
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• 2003.04a
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• pp.47-47
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• 2003

본 연구의 목적은 중국의 북경과 상해에 거주하는 성인 여성의 체형을 각 거주 지역(북경ㆍ상해)의 연령대(20대, 30대, 40대)별 신체적 특성을 파악하는 것이다. 연구문제는 다음과 같다. 1. 중국 성인 여성의 각 거주 지역의 연령대별 신체 계측치를 비교한다. 2. 중국 성인 여성의 각 거주 지역의 연령대별 요인점수를 비교한다. 3. 중국 성인 여성의 각 거주 지역의 연령대별 유형의 분포 경향을 파악한다. 연구 방법은 중국 북경과 상해에 거주하는 20세에서 49세 성인 여성 578명을 대상으로 인체 계측하였다. (중략)

• Journal of Korean Academy of Oral and Maxillofacial Radiology
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• v.14 no.1
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• pp.7-16
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• 1984

구강점막 각 부위의 지각신경의 특징은 근년 생리학적 연구의 중요한 대상이 되어왔다. 일반적으로 생리학적 기능은 연령과 더불어 감소된다는 소견이 구강점막에서도 적용된다고 하나 이에대한 형태학적 지견을 중심으로 볼 때 그러한 감소가 순전한 기능저하의 결과인지 혹은 지각신경의 해부학적 형태변화에 의한 것인지에 대해서는 분명하게 알려진 것이 없다. 본 논문은 Spraque-Dawely와 Fischer 344 두종의 숫자 20마리를 이용하여 각종을 6개월과 30개월의 연령으로 2군으로 나누어서 연령에 따른 구강점막내 신경섬유와 신경종말의 전자현미경적 특성의 변환을 관찰하고, 단위면적당 분포하고 있는 신경요소의 변화를 정량해 보았던바 다음과 같은 결과를 얻었다. 1. 구강점막에 분포하는 신경섬유와 신경종말의 전자현미경적 형태에 있어서는 젊은백서와 늙은백서 사이에 인정할 만한 질적 차이가 없었다. 2. 연령증가에 따라 구강점막의 상피내 간격에 존재하는 신경요소는 전반적으로 감소하였다. 3. 이와 같은 감소는 신경섬유보다 신경종말의 경우 더욱 현저하게 나타났다.

• The Journal of the Petrological Society of Korea
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• v.23 no.4
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• pp.393-403
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• 2014

U-Pb ages were determined from the Yongyudo biotite granites from western parts of Gyeonggi massif. The results show that the emplacement age of the Yongyudo biotite granite is ca. 227-230 Ma. Such age result that is somewhat older than previous reported ages, suggesting further investigations for the timing and evolution of the Jurassic granites of the western Gyeonggi massif.

• Journal of the Korean Arthroscopy Society
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• v.7 no.1
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• pp.52-57
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• 2003

Purpose : To evaluate the morphologic measurement and microvasculature of the normal human meniscus in Korean and to compare the difference of microvasculature according to the age and anatomical location. Materials and methods : Menisci of 21 cadavers divided into 3 groups according to the age. Each meniscus was divided into 10 parts of which the width and area of microvasculature were measured. Results : The average width of the medial and lateral menisci were $10.49{\pm}02.92mm$ and $10.55{\pm}2.05mm$, respectively. The average area of the microvasculature measured $20.29{\pm}8.44\%$ in the medial meniscus and $18.99{\pm}7.03\%$ in the lateral meniscus. The microvasculature of the medial meniscus was most abundant in the anterior horn and least abundant in the posterior horn (p<0.05). The lateral meniscus showed the most vessels in the posterior horn (p<0.05). The microvasculature of popliteal hiatus was not avascular but hypovascular. The area of microvasculature decreased with increasing age in all parts of the medial meniscus and body and posterior horn of the lateral meniscus (p<0.05). Conclusion : Differences in the anatomical distribution of the vessels were noted of both the medial and lateral menisci. The area of microvasculature generally decreased proportionally with increasing age in both medial and lateral meniscus.

• Pediatric Infection and Vaccine
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• v.17 no.1
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• pp.16-22
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• 2010

Purpose : We aimed to investigate the clinical and phylogenetic characteristics of Escherichia coli Urinary Tract Infections (E. coli UTI). Methods : We enrolled patients with culture-proven E. coli UTI, who were admitted at the study hospital from September 2008 to August 2009. We investigated clinical data of patients with E. coli UTI and characteristics of isolated E. coli strains. The phylogenetic groups were classified using triplex polymerase chain reaction (PCR), and the distribution of nine virulent genes was determined by multiplex PCR. Results : A total of 47 patients have participated in this study. Thirty (63.8%) were under 6 months; eight (17.0%) were between 6-12 months; and nine (19.1%) were over 12 months. We compared two age groups between under 6-month and over 6-month. In the age group under 6-month, higher proportion of male (P =0.002) and group B2 strains (P =0.020) were observed. In contrast, higher proportion of female and group non-B2 strains were observed in age group over 6-month. Frequencies of papC, papGII, papGIII, sfa/foc, hlyC, cnf1, fyuA, iroN and iucC were estimated as 68.1%, 57.4%, 42.6%, 46.8%, 46.8%, 31.9%, 87.2%, 48.9% and 63.8%, respectively. In the comparison of phylogenetic groups, group B2 showed higher distribution of virulent genes, while group D included more strains resistant to trimethoprim/sulfamethoxazole (TMP/SMZ) than other groups. Conclusion : We showed the age group-specific difference in the distribution of sex ratios and phylogenetic groups; more male and group B2 strains in age group under 6-month, while more female and group non-B2 in age group over 6-month. However, further evaluation including larger number of patients will be necessary to confirm above thesis in future molecular epidemiological studies.

• Journal of Korean Ophthalmic Optics Society
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• v.9 no.2
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• pp.211-221
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• 2004

The purpose of this study is to evaluate the distribution and change of curvature of the anterior corneal surface with age in emmetropia. 504 subjects who have emmetroia with good naked vision of at least 0.6-1.0 (spherical equivalent: +0.75D- -0.75D) participated in this study. The 504 subjects into 8 groups with 10 year interval from 3-year to 83-year, and their corneal curvatures were analyzed using manual keratometry. The results are as follows. In individual analysis: First, regression analysis of corneal curvature radius with age has given an equation: Y = -0.003x + 7.796 (r = -0.26). The average corneal curvature radii was measured to be $7.68{\pm}0.25mm$ at 38.3-year and range was 6.98-8.54 mm. Second, frequency of corneal curvature radius were obtained in 36% between 7.61 and 7.80 mm, 78% between 7.41 and 8.00 mm, 96% between 7.21 and 8.20 mm, 100% between 6.98 and 8.54 mm. Third, as for the comparison of corneal curvature radius with respect to sex, The mean value of male (n = 304, mean: 37.6-year $7.72{\pm}0.24mm$, Range: 7.09-8.54 mm) is larger than that of female (n = 200, mean: 39.3-year $7.62{\pm}0.24mm$, Range: 6.98-8.42 mm) by 0.1mm (p<0.01). In groups analysis: First, regression analysis of corneal curvature radius with age has given an equation: $Y=-0.0066x^2+0.0227x+7.7282$ (r = -0.90). Second, vertical and horizontal curvature radius decreased with age (p < 0.01). Especially the decrease of horizontal curvature radius were more pronounced than the decrease of vertical (horizontal:10-70 age group: 0.38 mm decrease, vertical:10-70 age group: 0.20 mm decrease). Third, difference between steep and flat meridian (astigmatism) progressively decreased with age. (low age group:0.18 mm difference, high age group: 0.08 mm difference). Fourth, the corneal curvature radius of male was larger than female's in total groups(p < 0.01). Consequently, the change of corneal curvature radius with age progressively decreased in all conditions (mean, vertical, horizontal, male, and female) and this change was more outstanding in horizontal rather than in vertical.