• 한국지리정보학회지
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• 제14권1호
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• pp.84-93
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• 2011

제방선 지도화는 하천지역의 환경보호와 하천 범람 방지, 그리고 하천 개발에 있어 매우 중요하다. 라이다(LiDAR)와 항공 정사영상(aerial ortho-image)과 같은 원격탐사 데이터의 활용은 대상 지역에 접근하지 않고도 대상 지역에 관한 지형 정보를 얻을 수 있다는 점 때문에, 하천 지도화 작업에 효율적이다. 라이다 자료는 얕은 물을 관통하는 능력과 높은 수직 정확도 때문에 하천구역 지도화 작업에 활용되어 오고 있다. 영상자료의 활용 또한 영상처리 기법을 이용하여 여러 특징들을 추출할 수 있다는 점 때문에 하천 지도화 작업에 효율적이다. 본 논문에서는 라이다와 항공 정사영상을 각각 활용하여 3차원 제방선 지도화 작업을 수행하였다. 그리고 지상 실측정보들을 통해 두 자료로부터 추출된 제방선들의 정확도를 측정하고, 두 측정 결과들을 비교한다. 통계적인 결과에서 나타나듯이 라이다를 활용하여 추출된 3차원 제방선이 항공 정사영상을 활용하여 추출된 3차원 제방선에 비해 수평 및 수직 정확도가 훨씬 더 높다는 것을 보여준다.

• 융합정보논문지
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• 제7권3호
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• pp.97-103
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• 2017

본 논문에서는 가시광 통신 시스템에서 디밍 제어를 위한 Zero Reduction Code (ZRC)의 다양한 부호화율 및 채널 조건에서 성능 분석을 진행함으로써, ZRC 부호의 특성 일반화 고찰을 목표로 한다. 이를 위해 무선 광 통신 시스템의 LOS (Line-Of-Sight)와 NLOS (Non-LOS) 채널의 특성을 설명하고, (5, 4), (6, 5), (7, 6)ZRC 부호화율에서 디밍 과 BER (Bit Error Rate)측면에서 모의실험을 통해 성능 분석을 진행하였다. 모의실험 결과, 3가지 타입의 부호화율에서 디밍 성능은 비슷하지만, NLOS 채널 환경에서 RMS (Root Mean Square) 지연 확산 값이 증가 될수록 상대적으로 높은 부호화율의 ZRC코드가 좋은 BER성능을 달성하는 것을 확인 하였다. 따라서 향후 가시광 통신시스템에서 ZRC를 이용한 디밍 제어 기술을 설계할 때 본 연구에서 분석한 결과를 통해 채널 상태에 따른 부호화율을 결정하는데 도움이 될 것으로 예상된다.

• Asian Pacific Journal of Cancer Prevention
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• 제14권10호
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• pp.6109-6114
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• 2013

Aim: To determine whether beta-blockers (BBs) improve the overall survival (OS) of patients with metastatic non-small cell lung cancer (NSCLC). Materials and Methods: The medical charts of 107 patients with metastatic NSCLC were retrospectively assessed. Thirty-five patients (BB group) using BBs during chemotherapy (CT) were compared with 72 controls [control=(C) group] who did not use BBs following the diagnosis of NSCLC. The histological tumor subtype, performance status (ECOG), age, gender, smoking status, comorbidities, other medications and chemotherapeutics that were received in any line of treatment were recorded. We compared the overall survival (OS) of the patients in the BB and C groups. Results: The mean age of the patients was 61 years (range 42-81 years) and all patients were administered CT. The BB group was more likely to have HT and IHD and was more likely to use RAS blockers (p<0.01 for all) compared with the C group, as expected. The mean follow-up time was 17.8 months (range 1-102 months) for the entire group. The most commonly prescribed BB agent was metoprolol (80% of cases). At the time of the analysis, 74 (69%) of all patients had died. In the univariate analysis the median overall survival (OS) was 19.25 (${\pm}2.87$) months (95%CI: 13.62-24.88) in the BB group and 13.20 (${\pm}2.37$) months (95%CI: 8.55-17.85) in the C group (p=0.017). However, the benefit of BBs on survival disappeared in the multivariate analysis. Conclusions: The use of BBs during CT may be associated with an improved OS for patients with metastatic NSCLC.

• Environmental Analysis Health and Toxicology
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• 제24권3호
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• pp.203-211
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• 2009

A lesser degree of research is available with respect to indoor radon characteristics associated with occupants' exposure. The present study evaluated the radon levels in several public-access buildings or underground facilities, and their temporal variation in underground facilities. Radon measurements were conducted in 2005 and 2006, utilizing a continuous radon detector. A solid alpha detector (RAD7) was utilized to measure indoor radon levels. The mean radon concentrations obtained from the building or facilities were in a descending order: platforms of Daegu subway line 2, 2005 (32 $Bq/m^3$), hot-air bathroom (14 $Bq/m^3$), basement of office building (14 $Bq/m^3$), underground parking garage (14 $Bq/m^3$), underground shop (12 $Bq/m^3$), nursery (10 $Bq/m^3$), platforms of Daegu subway line 2, 2006 (9.0 $Bq/m^3$), platforms of Daegu subway line 1, 2006 (8.9 $Bq/m^3$), supermarket (7.9 $Bq/m^3$), hospital (7.3 $Bq/m^3$), and second-floor of office building (5.7 $Bq/m^3$). In general, underground-level facilities exhibited higher radon levels as compared with ground-level facilities. It was suggested that ventilation is an important parameter regarding the indoor levels of a subway. There was a decreasing or increasing trend in hourly-radon levels in a subway, whereas no trend were observed in a basement of office building. In addition, the radon levels in the subway lines 1 and 2 varied according to the platforms. The radon levels in the present study were much lower than those of previous studies. The average annual effective dose (AED) of radiation from indoor radon exposure was estimated to be between 0.043 and 0.242 mSv/yr, depending on facility types. These AEDs were substantially lower than the worldwide average AED (2.4 mSv/yr).

• Journal of Forest and Environmental Science
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• 제33권4호
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• pp.305-314
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• 2017

This study aimed to predict changes in forest area using a probability density function, in order to promote effective forest management in the area north of the civilian control line (known as the Minbuk area) in Korea. Time series analysis (2010 and 2016) of forest area using land cover maps and accessibility expressed by distance covariates (distance from buildings, roads, and civilian control line) was applied to a probability density function. In order to estimate the probability density function, mean and variance were calculated using three methods: area weight (AW), area rate weight (ARW), and sample area change rate weight (SRW). Forest area increases in regions with lower accessibility (i.e., greater distance) from buildings and roads, but no relationship with accessibility from the civilian control line was found. Estimation of forest area change using different distance covariates shows that SRW using distance from buildings provides the most accurate estimation, with around 0.98-fold difference from actual forest area change, and performs well in a Chi-Square test. Furthermore, estimation of forest area until 2028 using SRW and distance from buildings most closely replicates patterns of actual forest area changes, suggesting that estimation of future change could be possible using this method. The method allows investigation of the current status of land cover in the Minbuk area, as well as predictions of future changes in forest area that could be utilized in forest management planning and policymaking in the northern area.

• Neonatal Medicine
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• 제28권3호
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• pp.116-123
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• 2021

Purpose: The aim of this study was to estimate the effect of targeting risk factors for the control of central line-associated bloodstream infection (CLABSI) among high-risk infants in a tertiary neonatal intensive care unit (NICU). Methods: Infants admitted to the NICU and diagnosed with CLABSI from January to December 2013 were eligible for inclusion to the study. The CLABSI group (n=47) was matched in a 1:2 ratio to the control group (n=94) based on gestational age, birth weight, and Score for Neonatal Acute Physiology-II. Risk factors for CLABSI were identified using the Cox proportional hazard model, and analysis of the effect of these risk factors targeting infection control was performed. Results: The risk factors associated with CLABSI were prolonged central line dwell days (adjusted hazard ratio [HR], 1.028; 95% confidence interval [CI], 1.011 to 1.045; P=0.001), use of a silicone catheter (adjusted HR, 5.895; 95% CI, 1.893 to 18.355; P=0.002), surgical treatment (adjusted HR, 3.793; 95% CI, 1.467 to 9.805; P=0.006), and less probiotic supplementation (adjusted HR, 0.254; 95% CI, 0.068 to 0.949; P=0.042). By targeting these risk factors with a quality improvement initiative, the mean CLABSI incidence rate per 1,000 catheter-days decreased from 6.6 to 3.1 (P=0.004). Conclusion: Targeting risk factors for infection control significantly reduced the rate of CLABSI among high-risk infants in the NICU.

• 한국생활과학회지
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• 제21권2호
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• pp.241-256
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• 2012

Gas station consumers have become increasingly conscious of expanding choices and service options available at retail outlets. The purpose of this study was to determine key factors in customer choice of gas / service stations. This study seeks to identify key the relationship between socio-demographical variables and consumer choice, and consumer satisfaction and loyalty associated with gas / service station usage. The research instrument comprised of a questionnaire in the form of an on-line survey that was administered during November, 2010. A Total of 1,000 questionnaires were used in the final analysis. The collected data were treated with SPSS Windows 18.0 and analyzed in for frequency, percentage, mean, standard deviation, pearson's correlation analysis, and multiple regression analysis. The results of were as following: First, there was a strong positive relationship between involvement, satisfaction, loyalty of gas station service. Second, satisfaction was significantly affected by involvement, the frequency of gasoline purchases, the information route and customer's occupation. Third, loyalty was significantly affected by consumer satisfaction, involvement, frequency of gasoline purchases, information route and customer's occupation.

• 한국생활과학회지
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• 제21권3호
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• pp.489-503
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• 2012

Consumers' interest in health is increasing, and health-seeking consumption lifestyles, including comprehensive consumption behaviors related to physical health, mental health, and a healthy dietary lifestyle are becoming increasingly important to many people. The purpose of this study was to develop a health-seeking consumption lifestyle scale that could aid in determining effects of social status, perceived health status, and socio-demographical variables on health-seeking consumption lifestyles. Data were collected via an on-line survey of 500 respondents, all of whom were married women 20 year of age or older. The data were analyzed in terms of frequency, percentage, mean, standard deviation, factor analysis, t-test, one-way ANOVA, Pearson's correlation analysis, and multiple regression analysis. The results of this study are as following: First, health-seeking consumption lifestyle demonstrated three main factors: physical health-seeking consumption lifestyle, mental health-seeking consumption lifestyle and healthy dietary life seeking consumption lifestyle. Second, most respondents identified themselves with the middle class and perceived their health status positively. Third, health-seeking consumption lifestyle demonstrated significant differences based on socio-demographical variables. Fourth, health-seeking consumption lifestyle was significantly affected by social class, age, and health status comparisons within similar age groups.

• 한국환경복원기술학회지
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• 제13권3호
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• pp.36-45
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• 2010

To analyze the relationship between climatic factors (monthly mean temperature and total precipitation) and tree-ring growths of Quercus mongolica Fischer (Mongolian oak) with different topographic sites in Mt. Worak, more than 10 trees were selected from each of seven stands. Two cores from each tree were measured for ring width. After crossdating, each ring-width series was double standardized by fitting first a negative exponential or straight regression line and secondly a 60-year cubic spline. Seven stands were categorized in two groups using cluster analysis for tree-ring index patterns. Cluster I (four stands) was located in higher elevation (550-812 m) with aspects of east, west and northwest, and cluster II (three stands) was located in rather lower election (330-628 m) with aspects of north and northwest. The aspects of two clusters were not significantly different. Response-function analysis showed a significant positive response to March precipitation for both clusters. It indicates that moisture supply during early spring season is important to radial growth because the cambial growths of ring-porous species, such as Mongolian oak, start before leaf growth. Cluster II showed a positive response to the precipitation of middle and late growing season, too.

• Asian-Australasian Journal of Animal Sciences
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• 제27권6호
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• pp.784-790
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• 2014

In this study we aimed to evaluate the reduction in dimensionality of 20 linear type traits and more final score in 14,943 Holstein cows in Brazil using factor analysis, and indicate their relationship with longevity and 305 d first lactation milk production. Low partial correlations (-0.19 to 0.38), the medium to high Kaiser sampling mean (0.79) and the significance of the Bartlett sphericity test (p<0.001), indicated correlations between type traits and the suitability of these data for a factor analysis, after the elimination of seven traits. Two factors had autovalues greater than one. The first included width and height of posterior udder, udder texture, udder cleft, loin strength, bone quality and final score. The second included stature, top line, chest width, body depth, fore udder attachment, angularity and final score. The linear regression of the factors on several measures of longevity and 305 d milk production showed that selection considering only the first factor should lead to improvements in longevity and 305 milk production.