• 한국지리정보학회지
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• 제7권4호
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• pp.143-154
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• 2004

원격탐사는 각종 상업용 위성과 항공사진을 바탕으로 이루어진다. 그러나 이러한 자료는 연구자들이 원하는 시기와 장소에 따라 촬영되는데 자료 획득시, 기상조건 및 경제적 이유로 많은 어려움을 겪고 있다. 이러한 문제점을 해결하고자 본 연구에서는 소형비행기 및 초경량 비행기에 탈부착이 가능한 소형 다중분광 자동 항공촬영시스템(PKNU2)을 개발하였다. PKNU2호는 연구실 자체 보유한 고해상도 가시대역, 적외선대역 카메라를 이용하여 칼라영상 및 적외 영상을 획득하였다. 환경감시 등의 목적으로 칼라 적외 합성영상을 생성, 분석하였으나 그리 만족스러운 결과를 획득하지 못하였다. 또한 PKNU2호가 대용량 촬영은 가능하였지만 데이터 저장시간이 12초로 횡중복률 60%를 만족시키지 못하였다. 현재 우리는 PKNU2호의 단점을 극복하고자 가시대역과 적외선 대역의 자료를 한번에 획득할 수 있 칼라 적외선 분광카메라, 열적외 카메라, 그리고 영상의 실시간 저장이 가능한 MPEG board를 도입하여 헬리콥터에 탈부착이 가능한 소형 다중분광 자동 항공촬영시스템(PKNU3)을 개발하고 있다. 본 연구에서는 본격적인 촬영에 앞서 가치 있는 영상 획득을 위해 센서의 특성 평가를 실시, 센서의 분광 특성 보정 및 렌즈의 기하학적 왜곡 보정을 작업을 실시하였다.

• 복식문화연구
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• 제7권3호
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• pp.122-133
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• 1999

The purpose of this study was to classify the somatotype on obese boys of 9 to 11 years old and to make an offer the basis which would be suitable for basic pattern construction by studying of their characteristics, forms and shapes. For this study, data were analyzed by using of photographic measurements in regard to 40 variables. The factor scores used in factor analysis become the basis of determining the value of each variable of the cluster analysis. 1) Eight main factors were extracted from factor analysis. 2) Three types were classified by cluster analysis. 3) Correspondent analysis was applied to data of 4 types in anthropometry between 3 types in photometry.

• 대한가정학회지
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• 제40권2호
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• pp.67-86
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• 2002

The purpose of this research is to offer a method to derive the body shapes and pose factors with resets from analyzing factors by using the measurement values of human body. 297 male subjects in their twenties participated in this study. 54 anthropometric and 35 photographic measurements were taken from each subject. Data is the several typical items selected among items and you have to make an index value by using these typical items and convert it. The index has high correlation with each item, is easy to be measured and is to be used after selecting an important item in designing prototype. With results of analyzing reliability level by each item, correlation and items that factor loading is low, the item that the correlation is high is to be removed within the range that maintains the reliability level. Five factors of the front part and seven factors of the profile came to be derived from this kind of process.

• 대한원격탐사학회:학술대회논문집
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• 대한원격탐사학회 2005년도 Proceedings of ISRS 2005
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• pp.264-267
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• 2005

COMS (Communication, Ocean, and Meteorological Satellite) will be launch at end of year 2008. For speedy and security communication of COMS, KARl (Korea Aerospace Research Institute) decided encryption and compression design. Encryption design is based on DES (Data Encryption Standard), so that encryption key generation and management are important issues in COMS operation. And Compression is based on loss and lossless JPEG (Joint Photographic Export Group) standard. JPEG is one of generally using compression algorithm in image.

• 대한의용생체공학회:학술대회논문집
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• 대한의용생체공학회 1994년도 추계학술대회
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• pp.92-95
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• 1994

As computer systems to make medical practice easy are widely used, a special hardware system processing medical data fast becomes more important. To meet the urgent demand for high speed image processing, especially image compression and decompression, we designed and implemented the medical image CODEC (COder/BECoder) based on MISD(Multiple Instruction Single Data stream) architecture to adopt parallelism in it. Considering not being a standart scheme of medical mage compression/decompress ion, the CODEC is designed programable and general. In this paper, we use JPEG (Joint Photographic Experts Group) algorithm to process images fast and evalutate it.

• Fibers and Polymers
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• 제7권1호
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• pp.57-61
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• 2006

A study has been made on the quantification and evaluation of fabric pilling using two-dimensional and three-dimensional hybrid imaging methods. Two-dimensional imaging method was good for some samples while three-dimensional measurement method for others, according to the properties of their base fabric. Various image processing techniques as well as three-dimensional data processing algorithms were applied for the extraction of pills from measured data and a series of shape parameters have been defined for the objective evaluation of fabric pilling. An evaluation criterion that is compatible with the conventional evaluation method has been proposed by applying the new evaluation method to the current photographic standards.

• 전자통신동향분석
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• 제38권2호
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• pp.66-74
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• 2023

Holography is the most promising 3D imaging technology to faithfully record and reproduce light information. In addition, it is widely explored in metrology for applications such as microscopy and tomography because it can accurately measure 3D shapes. However, the data size of a digital hologram is very large, and the data characteristics are notably different from those of conventional 2D images. The Joint Photographic Experts Group (JPEG) is a group of experts from the International Organization for Standardization/International Electrotechnical Commission. This group develops and maintains standards for still image compression. In 2014, the JPEG released a new standard for 3D image compression called JPEG Pleno to represent light fields, point clouds, and holograms. Among them, JPEG Pleno Holography is the first international standard for hologram compression. We review recent advances in JPEG Pleno Holography standardization and discuss future directions of development.

• 전자공학회논문지CI
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• 제48권2호
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• pp.66-77
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• 2011

본 논문은 특징을 효과적으로 병합하여 계층적 색인구조를 적용하는 광고영상의 분류기법에 대한 체계적 방법을 제안한다. 본 방법은 온라인 및 오프라인 상의 광고 영상 정보 관리를 위한 효과적인 응용으로써, 특별히 광고 영상정보의 추적을 위한 전처리 과정을 제공한다. 이를 위하여 전체 영상에 대한 일반적 정보를 포함하는 전역특징과 영상의 지역적 특성에 기반하는 지역특징을 고려한다. 고안된 지역특징은 영상 회전, 스케일링, 잡음추가, 빛의 변화에 불변하여 아핀(Affine) 변환에 의한 화면 차 영상에 대하여도 신뢰성 높은 매칭 도를 얻을 수 있고 동질의 영상 쌍을 검색하는데 있어서도 높은 정확도를 보여준다. 제안 방법은 우선 전역특징으로 전체영상자료에서 다수의 영상 쌍들로 개략적인 영상 군을 구성한 후에, 영상군안에서 지역특징에 의한 동질 영상 쌍들 즉 정밀한 영상 군들로 분리하는 정밀 매칭을 실행한다. 실행시간을 단축하기 위해 전형적인 클러스터링으로 전역특성이 유사한 영상들끼리 그룹화 함으로서 지역특징에 의한 동질 영상 쌍 간 과도한 매칭 시간의 문제점을 극복한다.

• Archives of Plastic Surgery
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• 제48권3호
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• pp.269-277
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• 2021

Background The Sunnybrook facial grading scale is a comprehensive scale for the evaluation of facial paralysis patients. Its results greatly depend on subjective input. This study aimed to develop and validate an automated Sunnybrook facial grading scale (SBface) to more objectively assess disfigurement due to facial paralysis. Methods An application compatible with iOS version 11.0 and up was developed. The software automatically detected facial features in standardized photographs and generated scores following the Sunnybrook facial grading scale. Photographic data from 30 unilateral facial paralysis patients were randomly sampled for validation. Intrarater reliability was tested by conducting two identical tests at a 2-week interval. Interrater reliability was tested between the software and three facial nerve clinicians. Results A beta version of the SBface application was tested. Intrarater reliability showed excellent congruence between the two tests. Moderate to strong positive correlations were found between the software and an otolaryngologist, including the total scores of the three individual software domains and composite scores. However, 74.4% (29/39) of the subdomain items showed low to zero correlation with the human raters (κ<0.2). The correlations between the human raters showed good congruence for most of the total and composite scores, with 10.3% (4/39) of the subdomain items failing to correspond (κ<0.2). Conclusions The SBface application is efficient and accurate for evaluating the degree of facial paralysis based on the Sunnybrook facial grading scale. However, correlations of the software-derived results with those of human raters are limited by the software algorithm and the raters' inconsistency.

• Restorative Dentistry and Endodontics
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• 제48권2호
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• pp.13.1-13.11
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• 2023

Objectives: Natural extracts have been investigated as a biomimetic strategy to mechanically strengthen the collagen network and control the biodegradation of extracellular matrix. This study evaluated the effect of epigallocatechin-3-gallate (EGCG) on abfraction lesions prior to the composite resin. Materials and Methods: The sample consisted of 30 patients (aged between 28 and 60 years) with abfraction lesions located in 2 homologous premolars. The teeth were randomly assigned according to dentin treatment: 0.02% EGCG solution or distilled water (control). After enamel acid etching, the solutions were applied immediately for 1 minute. The teeth were restored with Universal Adhesive (3M) and Filtek Z350 XT (3M). Analyzes were done by 2 independent examiners using modified USPHS (retention, secondary caries, marginal adaptation, and postoperative sensitivity) and photographic (color, marginal pigmentation, and anatomical form) criteria at baseline (7 days) and final (18 months). The data analysis used Friedman and Wilcoxon signed-rank tests (α = 0.05). Results: At baseline, all restorations were evaluated as alpha for all criteria. After 18 months, restorations were evaluated as alpha for secondary caries, color, and marginal pigmentation. There was significant difference between baseline and 18 months (p = 0.009) for marginal adaptation and postoperative sensitivity (p = 0.029), but no significant difference were verified between treatments (p = 0.433). The EGCG group had a restoration retention rate of 93.3%, while the control group had 96.7%. Conclusions: The application of EGCG solution on abfraction lesions did not significantly influence the survival of the restorations based on clinical and photographic criteria.