• 한국지반공학회논문집
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• 제18권6호
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• pp.117-127
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• 2002

사면의 파괴면 형태를 간단한 비선형 함수로 모델링하여 해석하는 결정론적인 사면안정 해석은 지층의 복합 특성과 불연속적인 특성을 효과적으로 반영하지 못하는 단점이 있다. 따라서, 본 연구에서는 결정론적인 방법 보다 지층의 제반조건들을 다양하게 반영할 수 있는 임의 탐색기법인 유전자 알고리즘을 이용한 사면안정 해석 방법을 제시하였다. 제시된 방법의 적합성을 확인하기 위해 단일지층 및 복합지층을 대상으로 하여 제안된 방법과 결정론적인 방법을 비교.검토하였으며, 검토결과 유전자 알고리즘을 이용한 사면안정해석 방법의 적용성을 검증할 수 있었다. 또한 제시된 사면안정 해석 방법에 강우강도에 따른 지하수위의 변화 예측모델을 적용하여 보다 합리적인 사면안정 해석 방법을 제시하였다.

• Journal of Communications and Networks
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• 제17권4호
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• pp.394-405
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• 2015

This paper considers a wideband cognitive radio network which can simultaneously sense multiple narrowband channels and thus aggregate the detected available channels for transmission and proposes a novel cognitive radio system that exhibits improved sensing throughput and can save power consumption of secondary user (SU) compared to the conventional cognitive radio system studied so far. More specifically, under the proposed cognitive radio system, we study the problem of designing the optimal sensing time and power allocation strategy, in order to maximize the ergodic throughput of the proposed cognitive radio system under two different schemes, namely the wideband sensing-based spectrum sharing scheme and the wideband opportunistic spectrum access scheme. In our analysis, besides the average interference power constraint at primary user, the average transmit power constraint of SU is also considered for the two schemes and then a subgradient algorithm is developed to obtain the optimal sensing time and the corresponding power allocation strategy. Finally, numerical simulations are presented to verify the performance of the two proposed schemes.

• 한국실내디자인학회논문집
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• 제17권3호
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• pp.51-58
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• 2008

Lately, in public libraries, there are various service programs for child user by corresponding to importance of reading based education and also a variety of changes by accommodating family based cultural life style. Therefore there is a need for space planning based study on unit-data room. This study gives guide-line of space planning through categorizing of space plot and furniture lay-out in child data room. The researcher, as a first step, searched web sites of 29 data rooms of 26 libraries and summarized space plots and features of data rooms through in-person visits. Then the author made a categorization standard and did a general analysis of featured data rooms through multiple categorization steps. There are Basic Type, General Type, Book-Shelf Centered Type, Book-shelf Scattered type and Multi-Functional Type out of this categorization steps. In sum, six categorizing bases, dividing infant room from child room, space zonning, position of entrance, compactness of reading space, position of book-shelf and orientation of book-shelf will be important design standards for child data-room of future libraries and an effective guide-lines for other unit data-rooms.

• Imaging Science in Dentistry
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• 제49권1호
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• pp.35-43
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• 2019

Purpose: The goal of this study was to assess the accuracy and reliability of a low-cost portable scanner (Scanify) for imaging facial casts compared to a previously validated portable digital stereophotogrammetry device (Vectra H1). This in vitro study was performed using 2 facial casts obtained by recording impressions of the authors, at King's College London Academic Centre of Reconstructive Science. Materials and Methods: The casts were marked with anthropometric landmarks, then digitised using Scanify and Vectra H1. Computed tomography (CT) scans of the same casts were performed to verify the validation of Vectra H1. The 3-dimensional (3D) images acquired with each device were compared using linear measurements and 3D surface analysis software. Results: Overall, 91% of the linear Scanify measurements were within 1 mm of the corresponding reference values. The mean overall surface difference between the Scanify and Vectra images was <0.3mm. Significant differences were detected in depth measurements. Merging multiple Scanify images produced significantly greater registration error. Conclusion: Scanify is a very low-cost device that could have clinical applications for facial imaging if imaging errors could be corrected by a future software update or hardware revision.

• 한국보건간호학회지
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• 제34권3호
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• pp.391-404
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• 2020

Purpose: This study investigates the disaster preparedness behaviors of people residing in disaster areas and the factors affecting such behaviors, by examining the application of a Health Belief Model. Methods: A mixed-method approach was used for this study. Local residents were surveyed in Gyeongju and Pohang, which had experienced earthquakes one to two years earlier. Quantitative data (N=233) were collected through a questionnaire and analyzed using t-test, one-way ANOVA, Scheffe test and multiple regression. Qualitative data (N=11) were collected through focus group and individual interviews, and evaluated through content analysis. Results: Disaster preparedness behaviors scored 7.04 out of 18 points, and factors that significantly affected disaster preparedness included cut to action, marriage status, experience of education and training related to disaster, benefit-barriers factors of disaster preparedness behaviors, and gender. The focus group and individual interviews confirmed the contents corresponding to each variable of the disaster preparedness behaviors and heal belief model. Conclusion: The findings of this study indicate that in order to induce disaster preparedness behaviors as well as education and training opportunities related to disaster relief, we need to examine cue to action of disaster preparedness behaviors, benefits, and barriers for motivating interventions.

• The Plant Pathology Journal
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• 제38권4호
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• pp.304-312
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• 2022

Boxwood is a representative ornamental shrub that is widely used in landscaping horticulture. After pruning, damaged leaves or stems of boxwoods are unavoidably vulnerable to infection by various plant pathogens. Several boxwood diseases caused by fungi, such as Volutella blight and Macrophoma leaf spot, have been reported worldwide including Republic of Korea. In this study, we isolated and identified fungal pathogens of boxwood diseases that occurred in Korea and characterized their morphological and taxonomic characteristics. Boxwood samples showing blight symptoms were collected in Seoul, Republic of Korea, and the putative fungal pathogens Pseudonectria buxi, P. foliicola, and Neofusicoccum buxi were successfully identified. Investigation of the morphological features of the field isolates, including mycelial growth and conidial morphology, and phylogenetic analysis of multiple DNA barcode loci revealed that there were some morphological and genetic variations among isolates, but all of the analyzed isolates were closely related to the corresponding reference strains. We also found that P. foliicola strains were more virulent than P. buxi, and the N. buxi strains isolated in this study were weak pathogens or saprophytes. The results of our study will contribute to the development of control strategies for boxwood diseases caused by fungi and accelerate research on the complex ecology of boxwood diseases.

• International Journal of Naval Architecture and Ocean Engineering
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• 제13권1호
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• pp.163-177
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• 2021

Numerical simulations of the Vortex-Induced Vibration (VIV) about a large-scale flexible pipe subject to shear flow were carried out in this paper. Efficiency verification was performed firstly, validating that the proposed fluid-structure interaction solution strategy is competent in predicting the VIV response. Then, the VIV characteristics related to multi-mode and spanwise hybrid waveform about the flexible pipe attributed to shear flow were investigated. When inflow velocity rises, higher vibration modes are apt to be excited, and the spanwise waveform easily convertes from a standing-wave-dominated status to a hybrid standing-traveling wave status. The multi-mode or even multiple-dominant-mode is prone to occur, that is, the dominant mode is often followed by several apparent subordinate modes with considerable vibration energy. Hence, the shedding frequencies no longer obey Strouhal law, and vibration trajectories become intricate. According to the motion analysis concerning the coupled cross-flow and in-line vibrations, as well as the corresponding wake patterns, a tight coupling interaction exists between the structural deformation and the wake flow behind the flexible pipe. In addition, the evolution of the vortex tube along the pipe span and a strong 3D effect are observed due to the slenderness of the flexible pipe and the variability of the vortex shedding attributed to the shear flow.

• Asian Pacific Journal of Cancer Prevention
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• 제13권1호
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• pp.157-163
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• 2012

Objective: Glutathione S-transferases (GSTs) are multifunctional enzymes that play a crucial role in the detoxification of both the endogenous products of oxidative stress and exogenous carcinogens. Recent studies investigating the association between genetic polymorphisms in GSTs and the risk of adult brain tumors have reported conflicting results. The rationale of this pooled analysis was to determine whether the presence of a GST variant increases adult glioma susceptibility by combining data from multiple studies. Methods: In our meta-analysis, 12 studies were identified by a search of the MEDLINE, HIGHWIRE, SCIENCEDIRECT and EMBASE databases. Of those 12, 11 evaluated GSTM1, nine evaluated GSTT1 and seven evaluated GSTP1 Ile105Val. Between-study heterogeneity was assessed using ${\chi}^2$-based Q statistic and the $I^2$ statistic. Crude odds ratios (ORs) with corresponding 95% confidence intervals (CIs) were used to estimate the association between GSTM1, GSTT1 and GSTP1 polymorphisms and the risk of adult gliomas. Results: The quantitative synthesis showed no significant evidence to indicate an association exists between the presence of a GSTM1, GSTT1 or GSTP1 Ile105Val haplotype polymorphism and the risk of adult gliomas (OR, 1.008, 1.246, 1.061 respectively; 95% CI, 0.901-1.129, 0.963-1.611, 0.653-1.724 respectively). Conclusions: Overall, this study did not suggest any strong relationship between GST variants or related enzyme polymorphisms and an increased risk of adult gliomas. Some caveats include absence of specific raw information on ethnic groups or smoking history on glioma cases in published articles; therefore, well-designed studies with a clear stratified analysis on potential confounding factors are needed to confirm these results.

• 한국ITS학회 논문지
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• 제17권2호
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• pp.128-141
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• 2018

본 논문에서는 대표적인 6대 협력형 차량 안전 시스템 대한 잠재적인 사회적 안전효과를 분석하는 방법론을 제시하고자 한다. 협력형 차량 안전시스템의 도입 및 확산을 위해서는 사회적으로 어떠한 파급효과를 가져올지에 대하여 안전 시스템 별 정량적 분석이 필요하다. 국내에서 사고유형 기반으로 분석이 이루어진 사례들이 있으나, 사고 시나리오를 기반으로 한 분석방법론을 찾아보기 어렵다. 이러한 방법론을 제시하기 위해서 우선 승용차나 승합차만을 대상으로 한 국내 사망교통사고 데이터를 기반으로 사고 시나리오를 분류한다. 다음으로 사고 시나리오를 분석하여 협력형 차량 안전 시스템에 적용 가능한 시나리오를 선정하고 결과적으로 사망 사고 빈도수를 통해 안전 시스템의 잠재적인 사회적 안전효과를 정량적으로 제시한다. 마지막으로 안전효과의 정량적 분석을 이용하여 협력형 차량 안전 시스템의 인증을 위한 대표 평가 시나리오를 제시한다.

• 기본간호학회지
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• 제8권1호
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• pp.69-80
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• 2001

This study was done to investigate the relation of smoking temptation, stage of change in smoking cessation, nicotine dependency and perceived health status in middle aged men. Convenience samples of 176 subjects who were either smoked or used to smoke, aged between 30 to 64, living in Seoul and Kyungi province area in Korea were selected for the study. The data was collected from December 1, 1999 to June 30, 2000. The research instrument were Stage of Change of Smoking Cessation Measure (DiClemente et al. 1991). Smoking Temptation Measure (Velicer, DiClemente, Rossi, Prochaska. 1990), Perceived Health Status Measure (McDowell & Newell, 1996), and Nicotine Dependency Scale (FTQ: Fagerstrom, 1978). The data were analyzed using the SAS Program. The result of the study are as follows : 1. The analysis of variance and multiple comparison showed that according to the stage of change, there were significant mean differences in the three sub-factors of smoking temptation; 'positive affect situation (F=12.64, p=.0001)', 'negative affect situation (F=16.01, p=.0001)', 'habitual craving situation (F=14.43, p=.0001)' and nicotine dependency (F=4.12, p=.0033) The mean score for smoking temptation for the subjects who were in the precontemplation stage outweighed the mean score for smoking temptation for subjects who were in the maintenance stage. 2. Through discriminant analysis, it was found that negative affect situation was the most influential variable of the smoking temptation sub-factors which can be used to discriminate stage of change. 3. The analysis of Pearson correlation coefficients showed that there was a significant positive relation between nicotine dependency and negative affect situation of smoking cessation((r=0.2182, p=0.0045) and a significant negative relation between nicotine dependency and perceived health status(r=-0.2115, p=0.0059).