• 해양환경안전학회:학술대회논문집
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• 해양환경안전학회 2017년도 공동학술발표회
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• pp.37-37
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• 2017

• East Asian mathematical journal
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• 제38권2호
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• pp.143-164
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• 2022

Computer technology in mathematics teaching-learning is not for teaching computer but for improving mathematics teaching-learning with computer. It is shown the use of computer technology comparing with traditional approach provides students more opportunities in order to approach abstract structure. Computer activity provides not only understanding concepts of analysis and opportunity to investigate theory but also effective background in teaching analysis. We analyze students' computer usage level on analysis education by using computer usage level according to role of computer technology. We try to get an useful educational implication on analysis education applying MATLAB through qualitative research.

• KSII Transactions on Internet and Information Systems (TIIS)
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• 제10권1호
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• pp.381-394
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• 2016

The several noise level estimation algorithms that have been developed for use in image processing and computer graphics generally exhibit good performance. However, there are certain special types of noisy images that such algorithms are not suitable for. It is particularly still a challenge to use the algorithms to estimate the noise levels of complex textured photographic images because of the inhomogeneity of the original scenes. Similarly, it is difficult to apply most conventional noise level estimation algorithms to images rendered by the Monte Carlo (MC) method owing to the spatial variation of the noise in such images. This paper proposes a novel noise level estimation method based on histogram modification, and which can be used for more accurate estimation of the noise levels in both complex textured images and MC-rendered images. The proposed method has good performance, is simple to implement, and can be efficiently used in various image-based and graphic applications ranging from smartphone camera noise removal to game background rendition.

• 말소리와 음성과학
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• 제3권3호
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• pp.115-121
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• 2011

This paper examines how L2 speech production varies according to learner's L2 proficiency level. L2 speech production variations are analyzed by quantitative measures at word and phone levels using Korean learners' English corpus. Word-level variations are analyzed using correctness to explain how speech realizations are different from the canonical forms, while accuracy is used for analysis at phone level to reflect phone insertions and deletions together with substitutions. The results show that speech production of learners with different L2 proficiency levels are considerably different in terms of performance and individual realizations at word and phone levels. These results confirm that speech production of non-native speakers varies according to their L2 proficiency levels, even though they share the same L1 background. Furthermore, they will contribute to improve non-native speech recognition performance of ASR-based English language educational system for Korean learners of English.

• 대한기관식도과학회지
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• 제6권2호
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• pp.147-151
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• 2000

Background and Objectives： Metastasis to the submental and submandibular lymph nodes rarely occurs in squamous cell carcinoma of the larynx and hypopharynx. The aim of this study is to evaluate the effectiveness of level I neck dissection in squamous cell carcinoma of larynx and hypopharynx. Materials and Methods : Forty-three patients with pathologically positive cervical nodal involvement in squamous cell carcinoma of larynx and hypopharynx treated between 1989 to 1998 were reviewed. Fifteen patients were treated with neck dissection including level 1,28 patients were treated with neck dissection excluding the level 1. Results : The regional recurrence at the level I in patients treated with neck dissection excluding the level I, was shown in only one case (recurrence rate 3.6%), but this patient was efficiently managed with salvage operation and adjuvant radiotherapy. No recurrence was shown in patients treated with neck dissection including the level I. So, total recurrence rate at the level I was 2.3%. Conclusion : This study suggests that dissection of the level I is not justified in squamous cell carcinoma of larynx and hypopharynx even if metastasis to cervical lymph node was confirmed preoperatively (cN+).

• 한국입자에어로졸학회지
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• 제7권4호
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• pp.113-121
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• 2011

The aerosol nanoparticles are suspected to be exposed to workers in nanomaterial manufacturing facilities. However, the exposure assessment method has not been established. One of important issues is to characterize background level of nanoparticles in workplaces. In this study, intensive aerosol measurements were made at a $TiO_2$ manufacturing laboratory for five consecutive days in May of 2010. The $TiO_2$ nanoparticles were manufactured by the thermal-condensation process in a heated tube furnace. The particle number size distribution was measured using a scanning mobility particle sizer every 5 min, in order to detect particles ranging from 14.5 to 664 nm in diameter. Total particle number concentration shows a severe diurnal variation irrespective of manufacturing process, which was governed by nanoparticles smaller than 50 nm in diameter. During the background monitoring periods, significant peak concentrations were observed between 2 p.m. and 3 p.m. due to the infiltration of secondary aerosol particles formed by photochemical smog. Although significant increase in nanoparticle concentration was also observed during the manufacturing process twice among three times, these particle peak concentrations were lower than those observed during the background measurement. It is suggested that the investigation of background particle contamination is needed prior to conducting main exposure assessment in nanomaterial manufacturing workplaces or laboratories.

• 지질공학
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• 제27권4호
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• pp.463-474
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• 2017

본 연구는 화강암과 퇴적암지역에 위치하는 중저준위 경주방폐장의 불균질 배경 단열의 방향성, 밀도, 크기를 정량적으로 분석하였다. 불균질 배경 단열을 분석하기 위하여 지표지질조사, 전기비저항탐사, 공내 초음파주사검층 자료를 이용하였다. 연구지역 배경 단열의 정량화 분석을 위해서 부트스트랩 방법을 적용하였으며, 이에 의하여 위치에 따라 다양한 방향성을 가지는 단열들의 이방성을 합리적으로 특성화할 수 있었다. 단열 밀도는 단층 연장성을 고려한 단층거리의 역산값 및 전기비저항 평균값과 상관성을 보였으며, 평균 부피 단열 밀도($P_{32}$)는 $3.1m^2/m^3$로 나타났다. 중저준위 방폐물 처분 지하 사일로에서 측정된 단열과 지표 단층 정보에 의하면, 단열크기는 단열의 프랙탈 성질에 기초한 멱함수 법칙 분포에 따르며, 배경 단열의 반경은 1.5~86 m로 산정되었다.

• 센서학회지
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• 제22권6호
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• pp.410-414
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• 2013

As one of the effective methods for researching the objective tinnitus detection, the GPIAS (Gap Pre-pulse Inhibition of Acoustic Startle) measurement has been used to verify the existence of animal tinnitus objectively. The level and pattern of the background sound presented prior to a startle pulse are closely related with the GPIAS results. But the effect of the starting point of the background sound on animal startle responses has not been reported yet. In this paper, we present the implementation of a GPIAS measurement system based on an unconstrained enclosure to avoid animals' excessive constraint stress and deal with the animals' growth. After the performance of our implemented system has been tested through the animal experiment using 4 SD-rats, the effect of starting point of stimulus background sound on the startle response has been studied by the use of our implemented system. Through the results, it is verified that our system can measure the inhibition of animal startle responses due the gap pre-pulse for GPIAS calculation and the background sound starting point does not significantly effect on the startle response and the GPIAS values if the background sound continues for more than 300msec before a gap pre-pulse is presented.

• 가정과삶의질연구
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• 제8권2호
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• pp.101-118
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• 1990

The purpose of this study is to examine the stress level and factors percepted by the married women during family life, and to identify the related variables influencing on stress level. For this purpose, questionnaires were distributed to the 650 married women who have been living in seoul. Among them 463 data were selected. For data analysis, the statistical method such as the factor analysis frequency distribution percentile , t-test, ANOVA, Duncan's Multiple Range Test and Stepwise Regression Analysis were used. the major findings were summarized as follows; 1) The general tendancy of the stress level percepted by the married women during family life was relatively low. 2) The household background variables(age, level of education, income, type of family, number of children, status of employment ) have turned out to be significant on the stress level of married women except family type. 3) All the social-psychological variables(socio-economic status, communication interaction, resources perception, psychological satisfaction) showed significant differences according to the stress level percepted by the married women during family life. 4) The level of work identity was the important factor on the stress level percepted by the married women during family life. 5) In Stepwise Multiple Regression Analysis, the married women's stress level during family life was greatly influenced by variables such as the resource perception and the psychological satisfaction.

• 한국산학기술학회논문지
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• 제14권3호
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• pp.1090-1099
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• 2013

본 연구에서는 베이비부머의 사회활동 유형 별 삶의 만족도의 차이를 파악하는데 목적이 있다. 이를 위해 1955년에서 63년에 태어난 남녀 베이비부버 1,115명을 대상으로 하여 2011년 8-10월에 성별과 지역에 따른 할당표본을 하였다. 연구의 결과, 첫째, 베이비부머의 사회활동 유형은 3집단으로 나타났다. 36.8%가 속한 소극적 사회참여형은 소득활동이나 시민단체활동은 전혀 하지 않고 종교활동이나 가정내 활동을 하는 경우는 소수가 포함되었다. 주로 여성이 많고 후기베이비부머가 많고, 학력수준이나 가정소득이 다른 군집에 비해 낮으며 삶의 만족도 중간정도이다. 둘째. 33.8%가 속한 활동적 사회참여형은 소득활동을 포함하여 모든 사회활동에도 적극적이다. 여성이 많고 후기베이비부머가 많다는 점은 소극적 사회참여형과 유사하나 학력이나 가정 내 월평균 소득, 삶의 만족도 수준이 다른 군집에 비해서 가장 높다. 셋째, 29.4%가 속한 경제활동 중심형은 소득활동에는 참여하지만 문화활동, 시민단체활동, 교육활동, 혼자 시간보내기 등의 사회활동에는 참여하지 않는다. 전기와 후기베이비부머의 분포나 학력의 분포, 가정내 월소득은 다른 군집의 중간 수준이지만, 다른 군집과는 달리 남성이 많고 삶의 만족도 수준은 가장 낮다. 본 연구결과를 토대로 유형별로 베이비부머의 사회활동참여와 삶의 만족도를 향상시킬 수 있는 방안을 제시하였다.