• 대한산업공학회지
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• 제41권1호
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• pp.50-58
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• 2015

The research on autonomous vehicle that expected to greatly reduce accidents by driver's mistakes is increasing in the development of technology. The purpose of this research is to identify the factor that affect trust in autonomous vehicles and analyze the requirements of the driver in autonomous vehicles environment. Therefore, in this study, we defined the information and functions provided by the autonomous vehicles through the investigation of the prior studies, conducted a questionnaire survey and focused group interview (FGI). The results show that competency, error management were important factors influencing trust in autonomous vehicles and identified that driver took safety related information as high priority in autonomous vehicle. Also, it was identified that driver prefer to perform the multimedia function in autonomous vehicle environment. The study is looking forward to be the reference data for design of advanced autonomous vehicle. It will contribute to the improvement of the convenience and satisfaction of the drivers.

• 복식
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• 제65권7호
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• pp.101-117
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• 2015

Along with the development of overall internet service, online fashion communities appeared and have started to thrive. The growth of mobile service has led to an even bigger expansion of these communities, and will wield a strong influence for the foreseeable future. The purpose of our study is to investigate the relationship between the behavior of these fashion communities and personality characteristics of the community features. For our data analysis, our study used 302 men and women, aged from their 20's and their 40's. The study results are as follows: First, some features, such as interaction, entertainment, promotion, information, and system technique, were drawn as the factors of the online fashion communities. Second, we could divide the community behavioral types into three different groups: buyer, maven, and onlooker groups. Third, all three groups showed different community characteristics. The primary concern for the buyer group was promotion while the mavens and the on-lookers were most interested in information. Fourth, they also showed different demographic characteristics in terms of gender, age, duration of membership, on-line time per visit and number of visits per week. These results show that a new strategy is necessary for online fashion communities to differentiate themselves and their marketing to consumers and their community behavioral types.

• 한국지반공학회:학술대회논문집
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• 한국지반공학회 2009년도 춘계 학술발표회
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• pp.376-387
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• 2009

Piled raft foundation is a geotechnical composite construction to support the superstructure by pile-soil-raft interaction. General conventional design for piled raft doesn't consider the contribution of a raft. This is very conservative and requires more piles to satisfy the factor of safety. It is important to evaluate the load sharing features of piled raft. In this research, this characteristics of piled raft evaluated using both centrifuge and numerical modelings. The ultimate bearing capacity of piled raft foundation was also evaluated and predicted through comparisons of ultimate bearing capacity of single pile (SP), unpiled raft (UR), freestanding pile group (FPG) and piled raft (PR). $\xi_{pr}$ and $\eta$ were determined by centrifuge model tests to simply evaluate the ultimate bearing capacity of piled raft and bearing capacity of piled raft was predicted using the calibrated numerical model based on the centrifuge tests and laboratory tests data.

• Journal of the Korean Data and Information Science Society
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• 제21권6호
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• pp.1263-1270
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• 2010

60명의 환자들을 20명씩3개 그룹으로 나누어 각 그룹마다 다른 종류의 식이요법을 실시한 후 1주 간격으로 5주간에 걸쳐서 콜레스테롤 수치에 대한 반복측정 자료를 얻었다. 해당자료를 바탕으로 적합성여부와 유의성 검정을 실시한 결과 등분산 Toeplitz가 다양한 공분산행렬 형태들 중에서 가장 적합한 공분산구조 모형으로 판명되었다. 이 모형에서는 시점들 간의 상관계수는 0.64-0.78로 대체적으로 높은 상관관계들을 보여주고 있으며, 모수인자들의 유의성검정 결과, 시간효과는 대단히 유의하게 나타났으나, 처리 및 처리와 시간과의 교호작용효과는 유의하지 않은 것으로 판명되었다.

• Nuclear Engineering and Technology
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• 제51권5호
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• pp.1241-1250
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• 2019

This study mainly focused on the neutronics modeling of bubbles in bubbly flow in boiling water reactors. The bubble, ring and homogenous models were used for radial void fraction distribution. Effect of the bubble and ring models on the infinite multiplication factor and two-group flux distribution was investigated by comparing with the homogenous model. Square pitch unit cell geometry was used in the calculations. In the bubble model, spherical and non-spherical bubbles at random positions, sizes and shapes were produced by Monte Carlo method. The results show that there are significant differences among the proposed models from the viewpoint of physical interaction mechanism. For the fully-developed bubbly flow, $k_{inf}$ is overestimated in the ring model by about $720{\pm}6pcm$ with respect to homogeneous model whereas underestimated in the bubble model by about $-65{\pm}9pcm$ with a standard deviation of 15 pcm. In addition, the ring model shows that the coolant must be separated into regions to properly represent the radial void distribution. Deviations in flux distributions principally occur in certain regions, such as corners. As a result, the bubble model in modeling the void fraction can be used in nuclear engineering calculations.

• 한국항공운항학회지
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• 제31권1호
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• pp.68-78
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• 2023

This study aims to provide information necessary for developing a "Competency-Based Training and Evaluation Plan" for general aviation flight instructors in Korea. General aviation training experts designed a survey by selecting "Behavior Indicators" from the ICAO Flight Instructor Competency Model. This study analyses the importance of Behavioral Indicators, the level of instructor performance, and the training needs for flight instructors. According to the factor analysis, ICAO "Flight Instructor Competency Model" is found as a valid tool to measure general aviation flight instructor competencies. According to the training needs analysis, flight instructors training program needs to be improved on "Training Environment Management", "Teaching Method", and "Interaction" competencies. When compared with trainee group, flight instructors & examiners have a higher training demand for "Teaching & Learning Environment Management". This study suggests the flight instructor training program requires to be reorganized based on the competencies related to the flight instructor duties in the training environments.

• Nuclear Engineering and Technology
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• 제55권1호
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• pp.12-24
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• 2023

With the improvement of laser technology, the strategic needs of efficient and precise decontamination of various components in nuclear application units can be fulfilled by laser decontamination. The surface contaminants of nuclear facilities mainly exist both as loose contaminated layer and fixed oxide layer. The types of radionuclides and contamination layer thickness are closely related to the operation status of nuclear facilities, which have an important influence on the laser decontamination process. This study reviewed the mechanism of laser surface treatment and the influence of laser process parameters on the decontamination thickness, decontamination factor, decontamination efficiency and the distribution of aerosol particle. Although multiple studies have been performed on the mechanism of laser processing and laser decontamination process, there are few studies on the microscopic process mechanism of laser decontamination and the influence of laser decontamination on surface properties. In particular, the interaction between laser and radioactive contaminants needs more research in the future.

• Clinical and Experimental Reproductive Medicine
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• 제50권1호
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• pp.44-52
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• 2023

Objective: The DNA integrity of spermatozoa that attach to fallopian tube (FT) cells is higher than spermatozoa that do not attach. FT epithelial cells can distinguish normal and abnormal sperm chromatin. This study investigated the effects of sperm with a high-DNA fragmentation index (DFI) from men with unexplained repeated implantation failure (RIF) on the Toll-like receptor (TLR) signaling pathway in human FT cells in vitro. Methods: Ten men with a RIF history and high-DFI and 10 healthy donors with low-DFI comprised the high-DFI (>30%) and control (<30%) groups, respectively. After fresh semen preparation, sperm were co-cultured with a human FT epithelial cell line (OE-E6/E7) for 24 hours. RNA was extracted from the cell line and the human innate and adaptive immune responses were tested using an RT2 profiler polymerase chain reaction (PCR) array. Results: The PCR array data showed significantly higher TLR-1, TLR-2, TLR-3, TLR-6, interleukin 1α (IL-1α), IL-1β, IL-6, IL-12, interferon α (IFN-α), IFN-β, tumor necrosis factor α (TNF-α), CXCL8, GM-CSF, G-CSF, CD14, ELK1, IRAK1, IRAK2, IRAK4, IRF1, IRF3, LY96, MAP2K3, MAP2K4, MAP3K7, MAP4K4, MAPK8, MAPK8IP3, MYD88, NFKB1, NFKB2, REL, TIRAP, and TRAF6 expression in the high-DFI group than in the control group. These factors are all involved in the TLR-MyD88 signaling pathway. Conclusion: The MyD88-dependent pathway through TLR-1, TLR-2, and TLR-6 activation may be one of the main inflammatory pathways activated by high-DFI sperm from men with RIF. Following activation of this pathway, epithelial cells produce inflammatory cytokines, resulting in neutrophil infiltration, activation, phagocytosis, neutrophil extracellular trap formation, and apoptosis.

• Journal of the Korean Academy of Child and Adolescent Psychiatry
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• 제8권1호
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• pp.22-33
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• 1997

본 연구는 반응성 애착 장애 아동(Reactive Attachment Disorder, 이하 ‘RAD’)의 혼란된 부모-아동 관계를 애착이론의 입장에서 체계적으로 살펴보고자 하였다. 이를 위해 1994년 8월에서 1995년8월 사이 소아정신과에 내원한 RAD 아동과 어머니 20쌍과 비교집단으로 정상 아동과 어머니 20쌍을 대상으로, 아동에 대한 내적 실행 모델 면접(Working Model of Child Interview, 1986)과 낯선 상황 절차(Strange Situation Procedure, 1978), 부모-아동 상호작용 척도(Dyadic Parent-child Interaction Coding Scales, 1983)을 실시하여 어머니의 아동에 대한 내적 표상과 어머니의 내적 표상 유형과 아동의 애착 유형과의 관계, 내적 표상 유형에 따른 어머니-아동 상호작용 양상을 살펴보았다. 1) 대상 어머니들을 3가지 내적 표상 유형으로 분류해 본 결과, 비교 집단 어머니는 모두 균형된 표상으로 분류되었고 RAD 집단 어머니는 비개입된 표상(55%), 왜곡된 표상(45%)으로 분류되었다. 2) 어머니의 아동에 대한 내적 표상 유형은 아동의 애착 유형과 체계적으로 연관되었다. 균형된 표상의 어머니의 아동은 모두 안정 애착이었고 비개입된 표상 어머니의 82%는 그 아동이 불안/회피 애착으로 분류되었고 왜곡된 표상 어머니는 56%가 그 아동이 비조직/비일관 애착, 33%는 불안/저항 애착으로 분류되었다. 3) 어머니-아동 상호작용에서, 비개입된 표상의 어머니는 아동 중심 놀이에서 균형된 표상의 어머니에 비해 묘사적 진술, 반영적 진술, 묘사/반영적 질문을 적게 사용하였고 왜곡된 표상의 어머니는 균형된 표상의 어머니에 비해 직접 명령과 간접 명령을 많이 사용하였다. 장난감 정리하기 과제에서 비개입된 표상과 왜곡된 표상의 어머니는 균형된 표상의 어머니보다 직접명령, 간접명령을 더 많이 사용하였다. 위의 결과를 통해서 볼 때, 어머니의 아동에 대한 내적 실행 모델은 아동과의 애착 관계와 어머니-아동 상호작용에 중요한 요인으로서 혼란된 어머니-아동 관계를 이해하는데 효율적인 접근을 제공하며 아동에 대한 치료적 개입에 유용한 정보를 제공해 줄 것으로 생각된다.

• 영재교육연구
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• 제21권3호
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• pp.741-760
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• 2011

본 연구의 목적은 영재학생과 일반학생의 과흥분성 차이를 조사하고, 영재학생의 성별 및 학교급별에 따라 차이가 있는지 조사하는 것이다. 본 연구의 대상은 경기도 소재 P 교육지원청산하 영재교육원 영재학생 74명과 일반학생 196명으로 구성되었다. 과흥분성 측정도구로는 김영아(2008)의 연구에서 타당화가 검증된 OEQ II 검사지를 초등학생 수준에 맞게 수정하여 사용하였다. 본 연구를 통해 얻은 결과는 다음과 같다. 첫째, 영재학생과 일반학생의 과흥분성을 비교한 결과 과흥분성 총점 및 5가지 하위영역모두에서 유의미가 차이가 나타났다. 이는 과흥분성이 영재와 일반학생을 판별하는 도구로 활용이 가능함을 시사한다. 둘째, 영재학생의 성별에 따른 과흥분성을 비교한 결과 과흥분성 총점에서 여학생 영재가 남학생 영재에 비해 유의미하게 높게 나타났다. 과흥분성 하위영역 중에서는 감각적 과흥분성, 감성적 과흥분성 영역에서 여학생 영재가 유의미하게 높게 나타났다. 셋째, 영재와 일반학생, 그리고 성별에 따른 상호작용 효과를 조사한 결과 과흥분성 총점에서 학생, 성별에 따른 유의미한 상호작용 효과가 나타났다. 과흥분성의 하위영역 중에서는 심체적 과흥분성, 감각적 과흥분성 영역에서 유의미한 상호작용 효과가 나타났다. 넷째, 영재학생의 학교 급별에 따른 과흥분성을 비교한 결과 초등학교 영재학생과 중학교 영재의 과흥분성에는 통계적으로 유의미한 차이가 나타나지 않았다. 이러한 결과를 근거로 할 때, 과흥분성이 영재의 일관성 있는 특성임을 시사하는 것으로 영재판별도구로서의 활용 가능성이 논의되었다.