• The Korean Journal of Applied Statistics
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• v.28 no.3
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• pp.529-540
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• 2015

A cross-over design is frequently used in clinical trials (especially in bioequivalence tests with a parametric method) for the comparison of two treatments. Missing values frequently take place in cross-over designs in the second period. Usually, subjects that have missing values are removed and analyzed. However, it can be unsuitable in clinical trials with a small sample size. In this paper, we compare single imputation methods in a $2{\times}2$ cross-over design when missing values exist in the second period. Additionally, parametric and nonparametric methods are compared after applying single imputation methods. A Monte-Carlo simulation study compares type I error and the power of methods.

• Journal of the Korean Society of Food Science and Nutrition
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• v.43 no.5
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• pp.772-783
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• 2014

This study aimed to investigate the relationships between depressed mood and life style patterns, including smoking, alcohol drinking, and physical inactivity in Koreans aged 40 years, which is a critical life transition period. Based on the Life Transition Period Health Examination at the Korea Association of Health Promotion conducted in 2011 (n=27,684), participants were categorized into a depressed mood group and a non-depressed mood group based on the results of the Primary Mental Health Questionnaire. The depressed mood group showed higher tendency for smoking compared to the non-depressed mood group. Current and ex-smokers were about twice as likely to have a depressed mood as the non-smokers. The prevalence of nicotine dependency was significantly higher in the depressed mood group. The number of days and amount of alcohol consumption were significantly correlated with depressed mood. The prevalence of alcohol dependence and alcohol abuse was higher in the depressed mood group than in the non-depressed mood group. The frequency of high-intensity exercise per week was negatively correlated with the number of people with a depressed mood. This study showed the significant relationships between depressed mood and smoking, alcohol drinking, and physical activity in adults during an important life transition period. This implies that the development of proper lifestyle intervention or education may be needed to prevent depressed moods in this age group.

• The Transactions of the Korea Information Processing Society
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• v.5 no.12
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• pp.3109-3116
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• 1998

본 논문에서는 대규모 병렬컴퓨터의 구현에 적합한 위상구조인 교차메쉬구조에서, 균등한 메시지분포를 갖고 메시지의 경쟁이 있는 실제적 상황에서 상호접속망내의 메시지의 경로를 선정하기 위한 방법들을 제안하고, 이의 성능을 검증하기 위해 우회 경로설정 알고리즘을 이용하여 시뮬레이션을 하였다. 교차메쉬의 특성상 최적경로의 수가 다른 구조들에 비해 다양하다는 특징을 이용하여 최적경로의 수를 우선순위에 반영한 우회조건 및 대각방향의 링크를 효율적으로 활용하기 위한 링크선정방법에 따를 교차메쉬의 최대지연(maximum delay), 평균지연(average delay) 및 메시지처리율(throughput)을 구하고 이를 비교 고찰하였다. 메시지 전송시 최적인 경로상의 링크에 경합이 생길 경우 최적 경로의 수가 적은 메시지가 높은 우선순위를 가지며 만약 같은 조건이라면 우회한 횟수가 많은 메시지가 높은 우선순위를 갖는 우회조건 LD를 사용하며 이 우선순위에 따라 경로를 선정할 차례가 된 메시지가 선택할 수 있는 최적경로의 수가 많을 경우 대각방향의 링크로 우선적으로 전송할 경우, 오래된 메시지가 높은 우선순위를 갖는 우회조건 A에 의한 방법에 비해 최대지연, 평균지연 및 메시지처리율에 있어서 각각 이상값에 대한 개선목표치의 약58%, 70% 및 31%의 성능개선이 있었다.

• The Journal of Korean Society for School & Community Health Education
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• v.20 no.1
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• pp.97-111
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• 2019

목적: 최근 이명의 발생률이 증가하고 있으나 이명에 대한 정확한 원인 발견이 어려운 실정이다. 한국의 경우도 예외는 아니며, 사회경제적 상태에 따른 이명여부를 분석하고자 한다. 방법: 국민건강영양조사 제 5기(2010-2012)의 원시자료를 이용하였으며, 연구 대상자인 40세 이상 12,041명을 다중 로지스틱 회귀분석을 실시하였다(95% CI). 결과: 40세 이상 중년인구의 사회경제적 상태에 따른 이명여부는 통계학적으로 유의한 차이가 있는 것으로 나타났다. 이명의 발생여부는 연령이 높을수록(p<.0001), 직업군에 따라서(p<.0001), 대사증후군이 있는 자(p<.0001), 교육수준이 낮을수록(p<.0001), 기초생활수급자(p<.0001), 배우자가 없는 자(p<.0001), 스트레스가 많을수록(p<.0001), 우울증이 높을수록(p=.0034) 이명이 발생하였다. 회귀분석 결과 여성의 경우 대상자의 학력이 초등학교 이하인 그룹에서 교차비가 높았으며(OR:1.784, 1.322-2.408) 소득이 하위계층인 그룹에서 교차비가 높았다(OR:1.591, 1.293-19.58). 하지만 남성의 경우에는 유의한 결과가 나오지 않았다. 결론: 본 연구는 40세 이상 중년인구의 사회 경제적 상태에 따른 이명여부를 파악함으로써 남성보다 여성에서 사회경제적 수준에 따라 이명여부에 영향을 많이 받는 것을 밝혀낸 것에 연구의 의의가 있다.

• Korean journal of applied entomology
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• v.29 no.3
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• pp.194-200
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• 1990

The diamondback moth (Plutella xylostella L.) was selected over 24 generations with fenvalerate. The resulting resistant strain was tested to study development of insecticide resistance and cross resistance to some insecticides in the laboratory. Insecticide resistance of diamondback moth at the 24th generation devleoped 66.2 fold compared to the parent strain for fenvalerate. The fenvalerate selected strain exhibited 145 fold, a high level of cross resistance to deltamethrin, and also showed 17.4-45.0 fold cross resistance to alphamethrin, cypermethrin, fenvalerate, permethrin, and tetramethrin in the pyrethroid insecticides. The fenvalerate selected strain showed 2.5-4.3 fold, low cross resistance to diazinon, dichlorvos, EPN, BPMC, cabaryl, and methomyl. However, it did not show cross resistance to acephate, fenitrothion, phenthoate, and carbofuran.

• Korean journal of applied entomology
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• v.33 no.4
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• pp.242-249
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• 1994

These studles were conducted to investigate the development of chem~cal resistance and cross.resista. nce m dlarnondback moth (Piuteiia xylostella L). The resistance development of diamondback moth greatly vaned under single selection of five insectlades. The tnflumuron and lambda cyhalothnn strains at 8th selected generation showed 374- and 29.l.fold resistant levels. respectively, as compared with the susceptible strain. However, the Baciilus thuringiensis-seleded at 8th selected generatLon exhibited 240-fold resistant level. and the prothiophos-selected at 8th generation revealed 14.3-fold resistant !eve1 while the cartap hydrochloride-selected at 8th generailon showed 9.1-fold resistant level Prothiophos- selected strain showed low cross-resistance level to cartap hydrochloride, while this strain exhibited no cross-resistance of 1.3 to 2.8-fold to other msectlcides. Cartap hydrochlonde- seleded strain showed 19.9-fold. a high cross-resistance to lambda cyhalothrin, but this strain showed 2.2-34 fold, no cross resistance to other insecticide. Lambda cyhalothnn-selected strain exhibited cross-resistance to cartap hydrochlolide and prothiophas. Triflumuron-seleded strain showed 1.3-4.9 fold. no cross-resistance to other ~nsectic~dTe he B. ihuring~ensis-selededs train showed no cross-resistance to other insecticides.

• Korean journal of applied entomology
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• v.30 no.1
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• pp.1-9
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• 1991

Cross-resistance and inheritance of resistance in laboratory-selected strains of the brown planthopper to various types of the insecticides were investigated. The fenobucarb-selected ($R_{f}$), carbofuran-selected($R_{c}$), and diazinon-selected($R_{d}$) strains were 50.3, 49.2 and 5.8 times less sensitive to the corresponding insecticides than th susceptible strain. both $R_{f}$ and $R_{c}$ strains were highly resistant to the other carbamate insecticides, and moderately resistant to cypermethrin and deltamethrin, but nearly not resistant to fenvalerate and the organophosphorus insecticides except malathion and phenthate. Moderate resistance to malathion and phenthoate in the $R_{f}$ and $R_{c}$ strains was obtained at the rate of 13.0-12.0 and 8.5-7.5 times, respectively. The $R_{d}$ strain showed low levels of resistance to the carbamate, organophosphorus and pyrethroid insecticides, but negatively correlated cross-resistance to fenvalerate. Resistance of the brown planthopper to all the test insecticides was inherited by partially dominant autosomal factor(s).

• Journal of Korean Society of Transportation
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• v.32 no.4
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• pp.410-420
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• 2014

This research suggests a new tram signal priority model which determines signal timings and tram intersection waiting time using analytical method. This model can calculate the signal timings for Early Green and Green Extension among the active tram signal priority techniques by tram detection time of upstream detector. Moreover, it can determine the tram intersection waiting time that means tram intersection travel time delay from a vantage point of tram travel. Under the active tram signal priority condition, priority phases can bring additional green time from variable green time of non-priority phases. In this study, the signal timing and tram intersection waiting time calculation model was set up using analytical methods. In case studies using an isolated intersection, this study checks tram intersection waiting time ranged 12.7 to 29.4 seconds when variable green times of non-priority phases are 44 to 10 seconds under 120 seconds of cycle length.

• Journal of Korean Society of Transportation
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• v.21 no.5
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• pp.97-110
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• 2003

The sight distance at unsignalized intersections is the one of the fundamental geometric design elements, and can ensure safety and efficient operations. Despite its importance, little research attention has been directed in Korea compared to developed countries such as European countries, the United States, and Japan. AASHTO ISD policies have been applied to the intersection design in Korea without any revise, which can produce unrealistic and unadoptable design values. Those values are emerged from several reasons because the AASHTO ISD has been calibrated based on the local data. Therefore the ISD hardly takes into account the local characteristics of Korea such as driving behavior. vehicular movement and roadway conditions. The objective of this study is to calculate the appropriate ISD values for unsignalized intersections in the urban area in Korea. In this study, we employed the ISD model of AASHTO(2001), which is based on gap acceptance theory and can account for and take the driving and roadway conditions in Korea into consideration. The approach can also consider the complex driving maneuvers at the intersections in a proper and simple manner. The results in this study show that the ISD design criteria currently used in Korea are more conservative(safer) than those of the USA. In other words, the ISD using field data collected in this study has generally smaller values than those in USA.

• Proceedings of the KAIS Fall Conference
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• 2011.05b
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• pp.941-946
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• 2011

본 연구는 직장암 검진에 영향을 미치는 요인을 규명하기 위해 시도하였다. 자료수집은 2011년 1월 10일부터 2월 23일까지 서울에 소재한 건강검진센터에 내원한 환자 211명을 대상으로 설문 및 면접조사를 하였다. 연구결과 첫째, 성별의 경우 남성 수검자는 74.2%로 비수검자 31.6%보다 유의하게 높은 분포를 보였다((p=0.035). 둘째, 흡연여부는 흡연자가 수검하는 경우는 47.4%, 비수검자는 25.4%로 두군간의 유의한 차이를 보였다(p=0.006). 셋째, 가족력이 있는 경우가 가족력이 없는 경우에 비해 교차비가 1.95로 유의하게 나타났다(95% Cl=1.69-3.41). 이러한 결과를 토대로 직장암 검진을 위한 적극적인 홍보를 위한 장-단기적인 전략을 세우는 것이 직장암 조기발견을 위한 효율적인 정책이라고 할 수 있겠다.