• Title/Summary/Keyword: 시각 편차

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Illumination Estimation Based on Nonnegative Matrix Factorization with Dominant Chromaticity Analysis (주색도 분석을 적용한 비음수 행렬 분해 기반의 광원 추정)

  • Lee, Ji-Heon;Kim, Dae-Chul;Ha, Yeong-Ho
    • Journal of the Institute of Electronics and Information Engineers
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    • v.52 no.8
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    • pp.89-96
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    • 2015
  • Human visual system has chromatic adaptation to determine the color of an object regardless of illumination, whereas digital camera records illumination and reflectance together, giving the color appearance of the scene varied under different illumination. NMFsc(nonnegative matrix factorization with sparseness constraint) was recently introduced to estimate original object color by using sparseness constraint. In NMFsc, low sparseness constraint is used to estimate illumination and high sparseness constraint is used to estimate reflectance. However, NMFsc has an illumination estimation error for images with large uniform area, which is considered as dominant chromaticity. To overcome the defects of NMFsc, illumination estimation via nonnegative matrix factorization with dominant chromaticity image is proposed. First, image is converted to chromaticity color space and analyzed by chromaticity histogram. Chromaticity histogram segments the original image into similar chromaticity images. A segmented region with the lowest standard deviation is determined as dominant chromaticity region. Next, dominant chromaticity is removed in the original image. Then, illumination estimation using nonnegative matrix factorization is performed on the image without dominant chromaticity. To evaluate the proposed method, experimental results are analyzed by average angular error in the real world dataset and it has shown that the proposed method with 5.5 average angular error achieve better illuminant estimation over the previous method with 5.7 average angular error.

A Study on a utilizing Mobile Mapping System for establishing the High Speed Outdoor Positioning DB based on Field Check Data (정위치 기반 고속 실외 측위 DB 구축을 위한 MMS활용 방안에 관한 연구)

  • Lee, Ha Dong;Lee, Yun;Choi, Yun Soo;Jeong, In Hun
    • Journal of Korean Society for Geospatial Information Science
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    • v.25 no.2
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    • pp.31-37
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    • 2017
  • Recently, governmental authority and local government are looking for a method of utilizing location information of smart phone for urgent rescue in fire and kidnap situation. Under this background, in this study, a method of rapidly collecting, constructing location determination based Wi-Fi AP data utilizing location information of smart phone and mobile mapping system was suggested in order to construct precise positioning information that could be utilized under urgent situation. By performing compensation work for GPS/INS/DMI through collected outcome, position of collected vehicle was acquired. In addition, source data integrating Wi-Fi information and collected position by coupling based on Wi-Fi AP collector and GPS time was constructed and Wi-Fi radiomap was constructed by removing Wi-Fi signal noise that reduces precise position performance. As a result of performing location determination performance assess ment by selecting 10 test positions by each local government, result value of 25.46cm for total local government average and 27.76m for SD could be obtained. It is considered that this result could be utilized as a technology of being able to supplement or substituting GPS location determination technology that is impossible in plocation determination of mobile communication company's base station (200m~2km) and indoor being used at present.

A Posterior Preference Articulation Method to the Weighted Mean Squared Error Minimization Approach in Multi-Response Surface Optimization (다중반응표면 최적화에서 가중평균제곱오차 최소화법을 위한 선호도사후제시법)

  • Jeong, In-Jun
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.16 no.10
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    • pp.7061-7070
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    • 2015
  • Multi-Response Surface Optimization aims at finding the optimal setting of input variables considering multiple responses simultaneously. The Weighted Mean Squared Error (WMSE) minimization approach, which imposes a different weight on the two components of mean squared error, squared bias and variance, first obtains WMSE for each response and then minimizes all the WMSEs at once. Most of the methods proposed for the WMSE minimization approach to date are classified into the prior preference articulation approach, which requires that a decision maker (DM) provides his/her preference information a priori. However, it is quite difficult for the DM to provide such information in advance, because he/she cannot experience the relationships or conflicts among the responses. To overcome this limitation, this paper proposes a posterior preference articulation method to the WMSE minimization approach. The proposed method first generates all (or most) of the nondominated solutions without the DM's preference information. Then, the DM selects the best one from the set of nondominated solutions a posteriori. Its advantage is that it provides an opportunity for the DM to understand the tradeoffs in the entire set of nondominated solutions and effectively obtains the most preferred solution suitable for his/her preference structure.

Analysis on Visibility of Delineators by Survey (시선유도시설 시인성 분석에 관한 연구)

  • Kwon, Sung-Dae;Park, Je-Jin;Nam, Chang-Kyu;Ha, Tae-Jun
    • KSCE Journal of Civil and Environmental Engineering Research
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    • v.32 no.5D
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    • pp.445-451
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    • 2012
  • Visual changes and speed changes in curved sections of highways are more dangerous than straight sections According to the enquetes conducted by Coalition for Transportation Culture in 1999, about 78% of drivers are dissatisfied with traffic guide and safety signs, with lack of visibility being the largest reason with about 27.9% of respondents indicating it as reason for dissatisfaction. In particular, the lack of visibility during nighttime or bad weather not only threatens driver safety due to poor delivery of information, but also affects the service level of highways. Because of this a new delineation must be installed and managed to enhance driver visibility. In this research, an optimal delineation system to enhance traffic safety is presented. In this research drivers effectively obtained information on highway alignment on the curved sections using a retro-reflection type delineation system and a newly-developed internal lighting delineation system to improve safety on the highways. A statistical comparison was conducted and analysis was done for the delineation systems that enhanced visibility through primary and secondary enquaetes. As a result, inside-lighting delineator will be selected in terms of safety at the curve sections. The inside-lighting delineator was more effective than the retro-reflection delineator on visibility, the necessity of reduction of speed and will reduce the hazard at curve sections. It is anticipated that when a delineation system based on this research is installed, a reduction in the number the number and severity of traffic accidents on curved sections will be reduced. In addition this system will more effectively provide drivers with information about highway alignment.

Perceptions of Elementary Teachers on Teaching Science-Arts Integrated Activities (과학-예술통합 활동에 대한 초등학교 교사들의 인식)

  • Mun, Jiyeong;Song, Joo-Yeon;Kim, Sung-Won
    • Journal of The Korean Association For Science Education
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    • v.33 no.5
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    • pp.1007-1020
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    • 2013
  • This study investigated the perceptions and the characteristics of elementary teachers on teaching science-arts integrated activities. Twelve elementary teachers who have taught in the third to sixth grade science lessons participated in this study. Data was collected by individual interviews lasting 60 to 90 minutes. Interview questions were composed of three aspects: 1) how elementary teachers perceive science-arts integrated activities, 2) in what ways elementary teachers address science-arts integrated activities, and 3) what difficulties elementary teachers experienced in addressing science-arts integrated activities. The results showed that, first, elementary teachers agreed that science-arts integrated activities have educational value in science learning. Second, most teachers focused on improving understanding of science knowledge through teaching science-arts integrated activities, while several teachers put emphasis on having experience of arts as well as understanding of science knowledge. And third, teachers experienced difficulties due to insufficient teaching materials and time to prepare for teaching science-arts integrated activities. Based on the results, we suggested educational implications for utilization of science-arts integrated activities in elementary education.

Contents Analysis of the Elderly Housing in the Unit "Family Life & Housing" - Focused on the 9th Grade Textbooks of Technology & Home Economics - (주생활 단원에서의 노인주거 관련 교과내용 분석 - 중학교 3학년 기술.가정 교과서를 중심으로 -)

  • Jang, Sang-Ock
    • Journal of Korean Home Economics Education Association
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    • v.20 no.2
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    • pp.31-46
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    • 2008
  • The purpose of this study is to analyze the contents of elderly housing in the unit "Family Life & Housing" in Technology & Home Economics 9th grade textbooks. The results of this study are as follows: First, the contents, illustrations, pictures, floor-plans, graphs and tables in current unit "Family Life & Housing" varied widely among textbooks and some didn't even contain these informations. Illustrations and pictures which are suit to the content and which contain positive image of space and living should be chosen. Second, most of the contents about elderly housing were concentrated on the life cycle, three-generation housing and universal design, discussed in chapter 'utility of living space.' The unification of overlapped contents and description which don't have stereotype about elderly housing are needed. Not only the interior environment but also the exterior environment of the elders and life-support service for them should be included in the contents. Contents that reflect the change of future population composition and the ratio of three-generation household are required. The elderly housing floor plan needs to be diversified in quantity such as ones which reflect the Korean characteristics or ones which enable person an independent life.

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Suggestion of Delineators Considering Traffic Safety at Curve Sections (교통안전을 고려한 곡선부 시선유도시설물 제시에 관한 연구)

  • Kwon, Sung-Dae;Lee, Suk-Ki;Jeong, Jun-Hwa;Ha, Tae-Jun
    • KSCE Journal of Civil and Environmental Engineering Research
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    • v.31 no.3D
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    • pp.403-412
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    • 2011
  • On a curve radius, there is speed deviation because a driver who is on the curve radius can have visual distortion. The curve radius can be more dangerous than a straight radius by many reasons. Especially, visibility paralysis of delineator that is because of night and bad weather. Can pervert the information about curve sections, it threatens safety. More over accident risk is increased by influence to travel speed. Therefore, it needs to build and control delineators for driver's visibility. Therefore, this study focus on finding the two types of delineator(the retro-reflection and inside-lighting delineator) by insight-surveying and the operating speed are compared by survey and operating speed. Finally, inside-lighting delineator will be selected in terms of safety at the curve sections. The inside-lighting delineator was more effective than the retro-reflection delineator on visibility, the necessity of reduction of speed and will reduce the hazard at curve sections. Also, the study analyzes safety is guaranteed by the slight reduction of speed when the driver enters a curve radius with inside-lighting delineator. As a result, the inside-lighting delineator can give the information about horizontal and vertical profile effectively, so it can reduce the accident risk. And it can use to improve traffic safety on curve radius.

The Ear Acupressure Therapy on Premenstrual Syndrome and Dysmenorrhea on Female college Students (이압 요법이 여대생의 월경 불편감에 미치는 효과에 관한 연구)

  • Choung, Hye-Myoung;Song, Ju-Seung
    • Journal of the Korea Society of Computer and Information
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    • v.18 no.5
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    • pp.87-94
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    • 2013
  • The purpose of this study is to identify the effect of ear acupressure therapy on premenstrual syndrome of the female college students. This research design of our study was a quasi-experimental design. Out of the 27 female college students, 13 were assigned to the experimental group and 14 to the control group. The data was obtained over 3 months from K college located in G city. The use of instrument to assess the premenstrual syndrome is Keele's VAS(Visual Analogue Scale) with the opening records. The subject of the experimental group received the ear acupressure therapy for 3 times for 60 days and the other control group did not get the ear acupressure therapy treatment. We analysed the data and extracted the values of percentage, mean, standard deviation, $x^2$-test, t-test, and Cronbach's ${\alpha}$ using SPSS program. The VAS score of the premenstrual syndromes before the ear acupressure therapy was 7.3(experimental group), 7.46(control group) but after the ear acupressure therapy, the VAS score of the premenstrual syndromes was 3.36(experimental group), 7.17(control group). The result of this study reveals that the ear acupressure therapy was effective in improving the symptoms of the female college students who had the premenstrual syndromes.

Regionalization of Extreme Rainfall with Spatio-Temporal Pattern (극치강수량의 시공간적 특성을 이용한 지역빈도분석)

  • Lee, Jeong-Ju;Kwon, Hyun-Han;Kim, Byung-Sik;Yoon, Seok-Yeong
    • Proceedings of the Korea Water Resources Association Conference
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    • 2010.05a
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    • pp.1429-1433
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    • 2010
  • 수공구조물의 설계, 수자원 관리계획의 수립, 재해영향 검토 등을 수행할 때, 재현기간에 따른 확률개념의 강우량, 홍수량, 저수량 등을 산정하여 사용하게 되며, 보통 대상지역의 장기 수문관측 자료를 이용하여 수문사상의 확률분포를 산정한 후 재현기간을 연장하여 원하는 설계빈도에 해당하는 양을 추정하게 된다. 미계측지역 또는 관측자료의 보유기간이 짧은 지역의 경우는 지역빈도 분석 결과를 이용하게 된다. 지역빈도해석을 위해서는 강우자료들의 동질성을 파악하는 것이 가장 기본적인 과정이 되며 이를 위해 통계학적인 범주화분석이 선행되어야 한다. 지점 빈도분석의 수문학적 동질성 판별을 위해 L-moment 방법, K-means 방법에 의한 군집분석 등이 주로 사용되며 관측소 위치좌표를 이용한 공간보간법을 적용하여 시각화하고 있다. 강수량은 시공간적으로 변하는 수문변량으로서 강수량의 시간적인 특성 또한 강수량의 특성을 정의하는데 매우 중요한 요소이다. 이러한 점에서 본 연구를 통해 강수지점의 공간적인 좌표 및 강수량의 양적인 범주화에 초점을 맞춘 기존 지역빈도분석의 범주화 과정에 덧붙여 시간적인 영향을 고려할 수 있는 요소들을 결정하고 이를 활용할 수 있는 범주화 과정을 제시하고자 한다. 즉, 극치강수량의 발생 시기에 대한 정량적인 분석이 가능한 순환통계기법을 이용하여 관측 지점별 시간 통계량을 산정하고, 이를 극치강수량과 결합하여 시 공간적인 특성자료를 생성한 후 이를 이용한 군집화 해석 모형을 개발하는데 연구의 목적이 있다. 분석 과정에 있어서 시간속성의 정량화 및 일반화는 순환통계기법을 사용하였으며, 극치강수량과 발생시점의 속성자료는 각각의 평균과 표준편차를 이용하였다. K-means 알고리즘을 이용해 결합자료를 군집화 하고, L-moment 방법으로 지역화 결과에 대한 검증을 수행하였다. 속성 결합 자료의 군집화 효과는 모의데이터 실험을 통해 확인하였으며, 우리 나라의 58개 기상관측소 자료를 이용하여 분석을 수행하였다. 예비해석 단계에서 100회의 군집분석을 통해 평균적인 centroid를 산정하고, 해당 값을 본 해석의 초기 centroid로 지정하여, 변동적인 클러스터링 경향을 안정화시켜 해석이 반복됨에 따라 군집화 결과가 달라지는 오류를 방지하였다. 또한 K-means 방법으로 계산된 군집별 공간거리 합의 크기에 따라 군집번호를 부여함으로써 군집의 번호순서대로 물리적인 연관성이 인접하도록 설정하였으며, 군집간의 경계선을 추출할 때 발생할 수 있는 오류를 방지하였다. 지역빈도분석 결과는 3차원 Spline 기법으로 도시하였다.

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Satisfaction Survey of Occupational Therapy Service at Specialized Child-care Centers for Disabled in Gyeongbuk (경북지역 장애아전문어린이집의 작업치료서비스에 대한 만족도 조사)

  • Kang, Suk-Gu;Lee, Chun-Yeop
    • The Journal of Korean society of community based occupational therapy
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    • v.5 no.1
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    • pp.55-62
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    • 2015
  • Objective : The purpose of this study was to investigate the satisfaction of occupational therapy service for parents of children with disabilities using specialized child-care centers for disabled in Gyeongbuk. Methods : The subjects of this study were 104 parents who have experience in occupational therapy at 14 specialized child-care centers for disabled in Gyeongbuk. A questionnaire was conducted from July, 2014 to March, 2015. Descriptive statistics of frequency, mean, standard deviation, and One-Way ANOVA study were used to analyze data. Results : Disabled children got occupational therapy at first when they were 3.25 years, on average. Duration of occupational therapy use were 31.84 month, on average. The subjects determined to got occupational therapy mostly through consultation nurseries(40.4%). Most of them got speech therapy(78.0%) other than receiving occupational therapy service, responded very necessary to occupational therapy(69.3%). Satisfaction of occupational therapy service were 4.49 point at attitude of occupational therapists, 4.36 point at occupational therapy program, and 4.26 point at environment of occupational therapy room. Attitude of occupational therapists were the highest satisfied. Conclusion : This study would contribute to effective and meaningful occupational therapy through objective view

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