• 대한원격탐사학회지
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• 제22권1호
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• pp.49-61
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• 2006

The lifting scheme has been found to be a flexible method for constructing scalar wavelets with desirable properties. In this paper, it is extended to the UDAR data compression. A newly developed data compression approach to approximate the UDAR surface with a series of non-overlapping triangles has been presented. Generally a Triangulated Irregular Networks (TIN) are the most common form of digital surface model that consists of elevation values with x, y coordinates that make up triangles. But over the years the TIN data representation has become an important research topic for many researchers due its large data size. Compression of TIN is needed for efficient management of large data and good surface visualization. This approach covers following steps: First, by using a Delaunay triangulation, an efficient algorithm is developed to generate TIN, which forms the terrain from an arbitrary set of data. A new interpolation wavelet filter for TIN has been applied in two steps, namely splitting and elevation. In the splitting step, a triangle has been divided into several sub-triangles and the elevation step has been used to 'modify' the point values (point coordinates for geometry) after the splitting. Then, this data set is compressed at the desired locations by using second generation wavelets. The quality of geographical surface representation after using proposed technique is compared with the original UDAR data. The results show that this method can be used for significant reduction of data set.

• 대한원격탐사학회지
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• 제24권2호
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• pp.205-211
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• 2008

현재까지 우리나라 하천관리는 기존의 도면관리 및 현장조사를 통한 정보관리에서 벗어나 WAMIS, RIMGIS와 같은 물 관련 하천기본지리정보 시스템을 구축하여 사용되어 왔다. 하지만 기 구축된 시스템들은 선(線) 중심의 9차원 하천 공간자료로 관리되어 실무자 중심의 친환경적 하천관리업무 지원을 위한 자료로서 활용성이 부족한 실정이다. 본 연구에서는 면(面) 중심의 입체적인 3차원 하천공간정보 구현과 체계적인 하천관리업무가 가능하도록 항공사진(아날로그, 디지털) 및 다양한 위성영상에 대한 해상도 비교와 시설물 판독 분석을 통한 하천 적용여부 분석을 수행하였다. 하천 적용성 분석을 통해 가장 효과적으로 판단되는 디지털 항공사진을 이용하여 하천관리 및 활용방안을 모색함으로써 효율적인 하천관리방안을 제시하고자 한다.

• 천문학회지
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• 제54권6호
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• pp.171-182
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• 2021

The lack of short baselines, referred to as the short-spacing problem (SSP), is a well-known limitation of the performance of radio interferometers, causing a reduction of the flux detected from source structure on large angular scales. The very large number of antennas operated in the Atacama Large Millimeter/sub-millimeter Array (ALMA) generates situations for which the impact of the SSP takes a complex form, not simply measurable by a single number, such as the maximal recoverable scale. In particular, extended antenna configurations, complemented by a small group of closeby antennas at the centre of the array, may result in a double-humped baseline distribution with a significant gap between the two groups. In such cases one should adopt as the effective maximal recoverable scale the one associated with the extended array and use only the central array to recover missing flux, as one would do with single dish or ACA (Atacama Compact Array) observations. The impact of the missing baselines can be very important and may easily be underestimated, or even overlooked. The present study uses ALMA archival data of the ²⁹SiO(8-7) line emission of the AGB star W Hydrae for a demonstration. A critical discussion of the reliability of the observations away from the star is presented together with comments of a broader scope. Properties of the circumstellar envelope of W Hya within ~15 au from the star, many of which are not mentioned in the published literature, are briefly described and compared with R Doradus, an AGB star having properties very similar to W Hya.

• 한국인터넷방송통신학회논문지
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• 제21권5호
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• pp.209-213
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• 2021

인체의 체형정보 중 신체 치수 측정기술은 줄자나 영상 분석을 이용한 체형 측정 방법들이 활용되고 있으나, 간편하면서도 측정 정확도나 재현성이 높은 방법에 대한 수요는 꾸준한 상황이다. 본 논문에서는 신체 치수 측정기술과 관련한 국내외 특허 조사를 수행하여 관련 기술의 개발 동향을 파악하였다. WISDOMAIN DB를 이용하여 한국, 미국, 일본 및 유럽에 공개된 특허를 대상으로 검색하였으며, 대분류, 중분류 기술체계와 소분류의 기술범위를 정의하여 유효 특허를 도출하였다. 도출된 특허에 대해 연도별 특허 동향, 국가별 주요 출원인과 기술 분야 현황을 분석하였다. 신체 치수 측정기술 분야는 한국의 특허출원 비중이 높아 이 분야에서 한국이 특허 출원을 주도하는 것으로 나타났다. 센서형 측정기술 분야의 특허 출원 건수 자체가 많지는 않았지만, 측정 간편성 부분에 장점이 있으므로 관련 기술개발은 체성분 분석 관련 측정 정확도 향상에 기여가 가능할 것으로 판단된다.

• 한국의류산업학회지
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• 제20권6호
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• pp.656-668
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• 2018

The main object of this study was to understand the body image and body management behavior associated with desiring a thinner and more muscular body. The present study examined whether the drives for thinness and muscularity occur concurrently for both male and female college students, and whether there are gender differences. Moreover, the effects of objectified body consciousness on drive for thinness and drive for muscularity were investigated. A self-administered survey was conducted and a total of 390 data were used for data analysis. Participants included 197 male college students and 193 female students. Results indicated that male students reported significantly lower drive for thinness and higher drive for muscularity than female students. However, the drives for thinness and muscularity were significantly correlated for both male and female college students, and they reported discrepancies between their BMI and self-perceived weight and muscle mass. Findings supported the significant effects of objected body consciousness on the drives for thinness and muscularity for both male and females. Sub-dimensions of objectified body consciousness had differential effects on drive for thinness and muscularity. Specifically, body surveillance and body shame significantly influenced male and female students' drive for thinness, while their control belief did not have significant effects on their drive for thinness. Additionally, body shame emerged as significant unique predictor of drive for muscularity. In terms of gender comparisons, while the effect of body shame was the strongest for the males, the effect of surveillance was as strong as that of body shame for the females.

• 디지털융복합연구
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• 제17권7호
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• pp.317-329
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• 2019

요즘 들어, 사진이나 이미지 중심의 소셜 네트워킹 서비스인 인스타그램은 학계와 업계의 주목을 받고 있다. 이러한 관심에도 불구하고 소비자들이 이 서비스를 사용하도록 유도하는 사회적, 심리적 요인에 대해서는 거의 알려진 바가 없다. 이러한 상황 속에서, 본 연구는 인스타그램 사용자에 대한 기본적인 이해를 제공하기 위해 250명의 참가자를 대상으로 인스타그램 사용자들에게서 나타나는 완벽주의적 자기제시 성향과 그 하위 요소를 찾아내고, 또한 이들과 인스타그램 사용의도 변수와의 관계를 탐구하였다. 그리고 자기 효능감과 자아 해석의 조절효과에 대해서도 살펴보았다. 이를 위해, 총 380명의 참가자를 예측된 가설과 연구문제를 검증하기 위해 모집하였다. 연구결과에 따르면 완벽주의적 자기제시는 다섯 가지 하위 요소인 타인의식적 자기제시, 주관적 자기제시, 환경적응적 자기제시, 자아 확장적 자기제시, 사회적 자기제시 등을 포함하고 있음을 확인하였다. 또한, 이러한 다섯 가지 요소를 지닌 완벽주의적 자기제시가 자기 효능감과 자아 해석의 조절효과를 통하여 인스타그램 사용의도에 긍정적인 영향을 미친다는 것을 밝혀냈다. 이러한 연구결과를 바탕으로 본 연구의 함의가 논의되었다.

• 한국초등과학교육학회지:초등과학교육
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• 제38권3호
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• pp.406-425
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• 2019

The purpose of this study is to analyze The Effect of Teacher Participation-oriented Education Program (TPEP) centered on Multi-Faceted Analysis of Elementary Science Classes on the Class Expertise of novice teacher. First, in order to develop the TPEP, lectures and exploratory science classes were analyzed using imaging and eye-tracking techniques. In this study, the TPEP was developed in five stages: image analysis, eye analysis, teaching language analysis, gesture analysis, and class development. Participants directly analyzed the classes of experienced and novice teachers at each stage. The TPEP developed in this study is different from the existing teacher education program in that it reflected the human performance technology aspects. The participants analyzed actual elementary science classes in a multi-faceted way and developed better classes based on them. The results of this study are as follows. First, at the teacher training institutions and the school sites, pre-service teachers and novice teachers should be provided with various experiences in class analysis and multi-faceted analysis of their own classes. Second, through this study, we were able to identify the limitations of existing class observations and video analysis. Third, the TPEP should be developed to improve the novice teachers' class expertise. Finally, we hope that the results of this study are used as basic data in developing programs to improve teachers' class expertise in teacher training institutions and education policy institutions.

• 정보처리학회논문지:소프트웨어 및 데이터공학
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• 제8권5호
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• pp.205-212
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• 2019

장면 그래프는 영상 내 물체들과 각 물체 간의 관계를 나타내는 지식 그래프를 의미한다. 본 논문에서는 3차원 실내 환경을 위한 3차원 장면 그래프를 생성하는 모델을 제안한다. 3차원 장면 그래프는 물체들의 종류와 위치, 그리고 속성들뿐만 아니라, 물체들 간의 3차원 공간 관계들도 포함한다. 따라서 3차원 장면 그래프는 에이전트가 활동할 실내 환경을 묘사하는 하나의 사전 지식 베이스로 볼 수 있다. 이러한 3차원 장면 그래프는 영상 기반의 질문과 응답, 서비스 로봇 등과 같은 다양한 분야에서 유용하게 활용될 수 있다. 본 논문에서 제안하는 3차원 장면 그래프 생성 모델은 크게 물체 탐지 네트워크(ObjNet), 속성 예측 네트워크(AttNet), 변환 네트워크(TransNet), 관계 예측 네트워크(RelNet) 등 총 4가지 부분 네트워크들로 구성된다. AI2-THOR가 제공하는 3차원 실내 가상환경들을 이용한 다양한 실험들을 통해, 본 논문에서 제안한 모델의 높은 성능을 확인할 수 있었다.

• Investigative Magnetic Resonance Imaging
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• 제25권2호
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• pp.118-128
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• 2021

Purpose: To investigate the value of MR textural analysis, including use of diffusion-weighted imaging (DWI) to differentiate malignant from benign soft-tissue tumors on 3T MRI. Materials and Methods: We enrolled 69 patients (25 men, 44 women, ages 18 to 84 years) with pathologically confirmed soft-tissue tumors (29 benign, 40 malignant) who underwent pre-treatment 3T-MRI. We calculated MR texture, including mean, standard deviation (SD), skewness, kurtosis, mean of positive pixels (MPP), and entropy, according to different spatial-scale factors (SSF, 0, 2, 4, 6) on axial T1- and T2-weighted images (T1WI, T2WI), contrast-enhanced T1WI (CE-T1WI), high b-value DWI (800 sec/mm²), and apparent diffusion coefficient (ADC) map. We used the Mann-Whitney U test, logistic regression, and area under the receiver operating characteristic curve (AUC) for statistical analysis. Results: Malignant soft-tissue tumors had significantly lower mean values of DWI, ADC, T2WI and CE-T1WI, MPP of ADC, and CE-T1WI, but significantly higher kurtosis of DWI, T1WI, and CE-T1WI, and entropy of DWI, ADC, and T2WI than did benign tumors (P < 0.050). In multivariate logistic regression, the mean ADC value (SSF, 6) and kurtosis of CE-T1WI (SSF, 4) were independently associated with malignancy (P ≤ 0.009). A multivariate model of MR features worked well for diagnosis of malignant soft-tissue tumors (AUC, 0.909). Conclusion: Accurate diagnosis could be obtained using MR textural analysis with DWI and CE-T1WI in differentiating benign from malignant soft-tissue tumors.

• 산업경영시스템학회지
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• 제43권4호
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• pp.93-106
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• 2020

This research explores how imported automobile companies can develop their strategies to improve the outcome of their recalls. For this, the researchers analyzed patterns of recall demand, classified recall types based on the demand patterns and examined response strategies, considering plans on how to procure parts and induce customers to visit workshops, recall execution capacity and costs. As a result, recalls are classified into four types: U-type, reverse U-type, L- type and reverse L-type. Also, as determinants of the types, the following factors are further categorized into four types and 12 sub-types of recalls: the height of maximum demand, which indicates the volatility of recall demand; the number of peaks, which are the patterns of demand variations; and the tail length of the demand curve, which indicates the speed of recalls. The classification resulted in the following: L-type, or customer-driven recall, is the most common type of recalls, taking up 25 out of the total 36 cases, followed by five U-type, four reverse L-type, and two reverse U-type cases. Prior studies show that the types of recalls are determined by factors influencing recall execution rates: severity, the number of cars to be recalled, recall execution rate, government policies, time since model launch, and recall costs, etc. As a component demand forecast model for automobile recalls, this study estimated the ARIMA model. ARIMA models were shown in three models: ARIMA (1,0,0), ARIMA (0,0,1) and ARIMA (0,0,0). These all three ARIMA models appear to be significant for all recall patterns, indicating that the ARIMA model is very valid as a predictive model for car recall patterns. Based on the classification of recall types, we drew some strategic implications for recall response according to types of recalls. The conclusion section of this research suggests the implications for several aspects: how to improve the recall outcome (execution rate), customer satisfaction, brand image, recall costs, and response to the regulatory authority.