• 한국대기환경학회지
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• 제13권1호
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• pp.51-63
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• 1997

Total suspended particulate matters in the ambient air were analyzed for eight chemical elements (Ca, Co, Cu, Fe, Mn, Pb, Si, and Zn) using an x-ray fluorescence spectrometry (XRF) at the Kyung Hee University - Suwon Campus during 1989 to 1994. To use these data as basis for source identification study, membership of each sample was selected to represent one of the well defined sample groups. The data sets consisting of 83 objects and 8 variables were initially separated into two groups, fine (d$_{p}$<3.3 ${\mu}{\textrm}{m}$) and coarse particle groups (d$_{p}$>3.3 ${\mu}{\textrm}{m}$). A hierarchical clustering method was examined to obtain possible member of homogeneous sample classes for each of the two groups by transforming raw data and by applying various distances. A disjoint principal component analysis was then used to define homogeneous sample classes after deleting outliers. Each of five homogeneous sample classes was determined for the fine and the coarse particle group, respectively. The data were properly classified via an application of logarithmic transformation and Euclidean distance concept. After determining homogeneous classes, correlation coefficients among eight chemical variables within all the homogeneous classes for calculated and meteorological variables (temperature. relative humidity, wind speed, wind direction, and precipitation) were examined as well to intensively interpret environmental factors influencing the characteristics of each class for each group. According to our analysis, we found that each class had its own distinct seasonal pattern that was affected most sensitively by wind direction.ion.

• 한국정보전자통신기술학회논문지
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• 제4권3호
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• pp.217-224
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• 2011

본 논문에서는 동적 데이터베이스 환경에서 발생할 수 있는 개인 정보 노출 문제를 해결할 수 있는 동적 데이터 보호 기법(Dynamic Data Protection Technique)을 제안하였다. 본 논문에서 제안한 DDPT은 다중 속성 일반화 알고리즘을 이용해 MAG(Multi-Attribute Generalization) 규칙을 생성하고, 그 MAG 규칙에 따라 k-anonymity를 만족하는 EC(Equivalence Class)를 생성한다. 그리고 데이터 변경 시 MAG 규칙에 따라 EC를 재구성 하도록 하여, EC의 변경으로 인한 식별 노출을 방지할 수 있다. 또한, ${\ell}$-diversity를 만족하는 EC의 정보손실 정도를 측정하고, 임계치 이하의 EC를 선정해서 데이터의 정확성을 유지함으로써 개인 정보 보호를 향상시켰다.

• 한국가정과교육학회지
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• 제15권1호
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• pp.15-32
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• 2003

This study examined teacher perception of the instructional method. activities and material in terms of class quality enhancement. Also this study established instructional method. activities and material application Per 7th Practical Arts Education Course guidance domain. and type identification of the instructional method and activities unique to the Practical arts curriculum. Conclusions : 1. Teachers consider the instructional method and material beneficial. However in the item relevant to application of diverse instructional methods Per specific teaching objective and educational content in the actual classroom. the highest percentage responding. ‘relatively yes’ (39.7%) . balanced out with those answering. ‘no’(37.7%) 2. In linking the instructional method and material to secondary school home economics education, teachers experienced difficulty in teaching only the clothing education domain . 3. In each guidance domain, lecture method, problem-solving learning. cooperative learning. home project learning and functional learning were surveyed for instructional method suitability. Notably, home project learning was identified as a significant instructional method. This result begs in-dept analysis as home project learning may be utilized as a tool to compensate for the absence of practical educational objective condition fulfillment and to substitute for teachers unable to Provide such functional guidance in class. 4. In each guidance domain. role-playing. debate/discussion. case study research, practical exercise and activity reporting were rated as essential teaching ㆍ learning activities. 5. In each guidance domain.‘VCR’, ‘CD-ROM’ and ‘Web media’ were identified as suitable instructional materials .

• 음성과학
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• 제6권
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• pp.197-217
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• 1999

In a noisy class, the acoustic-phonetic features of the teacher and the perceptual features of learners are changed comparison with a quiet environment. Acoustical analyses were carried out on a set of French monosyllables consisting of 17 consonants and three vowel /a, e, i/, produced by 1 male speaker talking in quiet and in 50, 60 and 70 dB SPL of masking noise on headphone. The results of the acoustic analyses showed consistent differences in energy and formant center frequency amplitude of consonants and vowels, $F_1$ frequency of vowel and duration of voiceless stops suggesting the increase of vocal effort. The perceptual experiments in which 18 undergraduate female students learning French served as the subjects, were conducted in quiet and in 50, 60 dB of masking noise. The identification scores on consonants were higher in Lombard speech than in normal speech, suggesting that the speaker's vocal effort is useful to overcome the masking effect of noise. And, with increased noise level, the perceptual response to the French consonants given had a tendency to be complex and the subjective reaction score on the noise using the vocabulary representative of 'unpleasant' sensation to be higher. And, in the point of view on the L2(second language) acquisition, the influence of L1 (first language) on L2 examined in the perceptual result supports the interference theory.

• 환경생물
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• 제38권2호
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• pp.289-298
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• 2020

As part of the research program "2018 Rapid screening and identification of freshwater microorganisms using MALDI-TOF/MS library" freshwater samples were collected from a branch of the Nakdong River. Almost 300 antibiotic-resistant bacterial strains were isolated from freshwater samples and subsequently identified by 16S rRNA gene sequencing. Seventeen strains among the isolates shared high 16S rRNA gene sequence similarity (>99.0%) with known species that were not previously recorded in Korea, and each of the isolates also formed a robust phylogenetic clade with the closest species. These species were phylogenetically diverse, belonging to four phyla, seven classes, 10 orders, and 13 genera. At the genus and class level, the previously unrecorded species belonged to Rhodovarius, Xanthobacter, and Shinella of the class Alphaproteobacteria; Ottowia, Simplicispira, and Zoogloea of Betaproteobacteria; Pseudomonas, Acinetobacter, and Shewanella of Gammaproteobacteria; Arcobacter of Epsilonproteobacteria; Sphingobacterium of Sphingobacteriia; Trichococcus of Bacilli; and Leucobacter of Actinobacteria. The previously unrecorded species were further characterized by examining their gram-staining, colony and cell morphology, biochemical properties, and phylogenetic position.

• 센서학회지
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• 제21권2호
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• pp.103-108
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• 2012

Radiofrequency(RF) signal is a key medium to the most of the present wireless communication devices including RF identification devices(RFID) and smart sensors. However, the most critical barrier to overcome in RFID application is in the failure rate in detection. The most notable improvement in the detection was from the introduction of EPC Class1 Gen2 protocol, but the fundamental problems in the physical properties of the RF signal drew less attention. In this work, we focused on the physical properties of the RF signal in order to understand the failure rate by noting the existence of the ground planes and noise sources in the real environment. By using the mathematical computation software, Maple, we simulated the distribution of the electromagnetic field from a dipole antenna when ground planes exist. Calculations showed that the dark area can be formed by interference. We also constructed a test system to measure the failure rate in the detection of a RFID transponder. The test system was composed of a fixed RFID reader and an EPC Class1 Gen2 transponder which was attached to a scanner to sweep in the x-y plane. Labview software was used to control the x-y scanner and to acquire data. Tests in the laboratory environment showed that the dark area can be as much as 43 %. One who wants to use RFID and smart sensors should carefully consider the extent of the dark area.

• 한국안전학회지
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• 제37권2호
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• pp.18-27
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• 2022

Construction accidents are difficult to prevent because several different types of activities occur simultaneously. The current method of accident analysis only indicates the number of occurrences for one or two variables and accidents have not reduced as a result of safety measures that focus solely on individual variables. Even if accident data is analyzed to establish appropriate safety measures, it is difficult to derive significant results due to a large number of data variables, elements, and qualitative records. In this study, in order to simplify the analysis and approach this complex problem logically, data preprocessing techniques, such as latent class cluster analysis (LCCA) and predictor importance were used to discover the most influential variables. Finally, the correlation was analyzed using an alluvial flow diagram consisting of seven variables and fourteen elements based on accident data. The alluvial diagram analysis using reduced variables and elements enabled the identification of accident trends into four categories. The findings of this study demonstrate that complex and diverse construction accident data can yield relevant analysis results, assisting in the prevention of accidents.

• 한국정보통신학회:학술대회논문집
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• 한국정보통신학회 2022년도 추계학술대회
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• pp.97-99
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• 2022

대장암의 조기 발견과 치료를 위해서는 정확한 폴립의 분할이 중요하나 다음과 같은 제약이 따른다. 개별 폴립의 위치, 크기 및 모양이 서로 상이하며, 모션 흐림 및 빛 반사와 같은 특정 상황에서 폴립과 주변 환경 간에 상당한 정도의 유사성이 존재한다. 인코더와 디코더 역할을 하는 Convolutional Neural Networks로 구성된 U-net은 이러한 한계를 극복하기 위해 다양하게 사용된다. 본 연구는 보다 정확한 폴립 분할을 위한 비전트랜스포머가 포함된 U-net 아키텍처를 제안하였고, 그 결과 제안된 방식은 표준 U-net 아키텍처보다 더 나은 성능을 보였음을 확인할 수 있었다.

• 한국정보처리학회:학술대회논문집
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• 한국정보처리학회 2023년도 추계학술발표대회
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• pp.540-542
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• 2023

Due to the serious issues posed by facial manipulation technologies, many researchers are becoming increasingly interested in the identification of face forgeries. The majority of existing face forgery detection methods leverage powerful data adaptation ability of neural network to derive distinguishing traits. These deep learning-based detection methods frequently treat the detection of fake faces as a binary classification problem and employ softmax loss to track CNN network training. However, acquired traits observed by softmax loss are insufficient for discriminating. To get over these limitations, in this study, we introduce a novel discriminative feature learning based on Vision Transformer architecture. Additionally, a separation-center loss is created to simply compress intra-class variation of original faces while enhancing inter-class differences in the embedding space.

• 자연과학논문집
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• 제8권2호
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• pp.289-321
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• 1996

조선 후기는 임진.병자 양난을 계기로 사회전반에 급격한 변화를 겪으며 근대 사회로의 전환기를 맞는다. 즉 전쟁으로 인한 국가제도의 문란과 혼란해진 사회구조 속에서 신분제도가 해이해졌고, 상업경제체제와 화폐경제의 발달로 인한 부유한 중인 계층이 대두되었고, 사상적으로는 유교가 공리공론에 빠지면서 유교윤리의 약화현상이 나타나면서 현실치중 의식을 보이는 실학사상이 등장 하였다. 또한 서민문예의 대두로 서민의식을 가진 서민계층(서민의식을 가진 양반계층 포함)이 등장하게 되었다.이 서민 계층의 등장은 복식에 있어서의 대중복식문화를 부각시키면서 유행현상이 출현되었다. 그리고 대중은 이 전환기 사회에서 변화된 그들의 역할과 가치관은 이제 더 이상 지배층에게서 영향력 행사할 충분한 권력이나 매력을 찾지 못했다. 따라서 이들은 새로운 상징적 선도자(Symbolic leaders) 즉, 모범을 보여주는 새로운 대상을 찾았고, 그들의 상징적 선도자는 바로 '자유분방하고, 사회활동을 하는 독립된 여성, 그리고 시와 가무를 즐기는 풍류가이고 또한 신체적으로 매력을 지닌 멋장이인' 기녀들 이었다. 선도자 그룹인 기녀계층에 의해 제시된 새로운 Fashion과 Style인 Erotic Mode와 사치 Mode는 그 시대 사조를 반영하면서 대중이 의식과 기호에 크게 맞아 떨어지자 큰 호응을 얻고 수용되었다. 즉 이들대중은 선도자 그룹을 모방 함으로써 그들과 자신들의 동일시를 성취하고 선도자의 Prestige를 나누어 가지고자 했던 것이다.이러한 이유로 해서 기녀들은 하류계층임에도 불구하고 조선후기 시대의 "패션의식적인"사회집단으로서 대중으로부터 주목받고 대중의 기호를 장악하며, 그들의 복식행동은 대중으로부터 강한 수용을 받게 되면서 대중의 의복 행동에 크게 영향을 미치는 유행선도자(Fashion leader)였음을 보게 된다.