• Title/Summary/Keyword: 이영식

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Real Time Eye and Gaze Tracking (실시간 눈과 시선 위치 추적)

  • 이영식;배철수
    • Journal of the Korea Institute of Information and Communication Engineering
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    • v.8 no.2
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    • pp.477-483
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    • 2004
  • This paper describes preliminary results we have obtained in developing a computer vision system based on active IR illumination for real time gaze tracking for interactive graphic display. Unlike most of the existing gaze tracking techniques, which often require assuming a static head to work well and require a cumbersome calibration process for each person our gaze tracker can perform robust and accurate gaze estimation without calibration and under rather significant head movement. This is made possible by a new gaze calibration procedure that identifies the mapping from pupil parameters to screen coordinates using the Generalized Regression Neural Networks(GRNN). With GRNN, the mapping does not have to be an analytical function and head movement is explicitly accounted for by the gaze mapping function. Futhermore, the mapping function can generalize to other individuals not used in the training. The effectiveness of our gaze tracker is demonstrated by preliminary experiments that involve gaze-contingent interactive graphic display.

Temporal variations of nutrients and chlorophyll-a in the Bottol Bada in July, 2004 (2004년 7월 봇돌바다의 영양염과 chlorophyll-a의 단기 변동)

  • Choi Yong-Kyu;Cho Eun-Seob;Kwon Kee-Young;Lee Yong-Hwa;Lee Young-Sik
    • Journal of Environmental Science International
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    • v.14 no.4
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    • pp.397-404
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    • 2005
  • In order to study the temporal variations of nutrients and chlorophyll-a in the Bottol Bada, three field observations were carried out on 20, 23 and 26 July, 2004. The low N:P values exhibit nitrogen deficiency during the periods of observation. This result is not representative of typical summer environment in the southern coast of Korea. The possible mechanisms are as follows: 1) The freshwater inflow was not sufficient for the supply of nitrogen because the total precipitation was 11.9 mm in July, 2004. This amount is no more than $5\%$ in normal precipitation in July. 2) There was an inflow of oceanic water under the subsurface into the Bottol Bada. Even though the oceanic water comprises more nutrients, it produces the stratification between the surface and the subsurface water and seems to prevent the supply of nutrinets to the surface layer. 3) The high chlorophyll-a concentration of $1.2 {\cal}ug/L$ was shown near the narrow channel between Gae-do and Geumo-do. This seems to be resulted from the inflow of water from Gamak Bay.

Analysis on Static Load and Resonance Frequency of Bed in High-speed Automatic Lathe for Precision Machining (정밀가공용 고속 자동선반 베드의 정하중 및 공진주파수 해석)

  • Ha, Joohwan;Lee, YunChul;Joo, KangWo;Jo, Eunjeong;Lee, Young-Sik;Lee, Jae-Kwan;Kim, Kwangsun
    • Journal of the Semiconductor & Display Technology
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    • v.16 no.2
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    • pp.32-38
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    • 2017
  • This paper is about the analysis on the vibration characteristic of tooling units on the precision bed in high-speed automatic lathe for precision machining. An automatic lathe operating at about 25,000 RPM is a critical factor in the self-weight stress and deformation of the bed. Especially, the resonance frequency should be grasped in advance to prevent abnormal vibration that may occur during processing. If the wrong bed is used, the resonant frequency can have a fatal influence on the precision machining and increase the defective rate of precision machined parts such as semiconductor parts. In this paper, vibration characteristics were evaluated through static load and resonance frequency analysis of automatic lathe bed. As a result, the maximum stress was 0.14MPa, the maximum deformation amount was $17.9{\mu}m$, and the natural frequency was 364.72Hz. The resonance frequency was calculated as 718Hz, and the stability was confirmed by being in the range of 400Hz or more, which is the processing condition.

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Analysis on Static Load and Resonance Frequency of Bed in Turning and Hobbing Automatic Lathe for Precision Machining (선삭 및 호빙 가공용 자동선반 베드의 정하중 및 공진주파수 해석)

  • Ha, Joo-Hwan;Lee, Yun-Chul;Jo, Eun-Jeong;Lee, Young-Sik;Lee, Jae-Kwan;Kim, Kwang-Sun
    • Journal of the Semiconductor & Display Technology
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    • v.17 no.1
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    • pp.66-70
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    • 2018
  • This paper is about the analysis on the vibration characteristic of tooling units on the precision bed in turning and hobbing automatic lathe for precision machining. An automatic lathe operating at about 12,000 RPM is a critical factor in the self-weight stress and deformation of the bed. Especially, the resonance frequency should be grasped in advance to prevent abnormal vibration that may occur during processing. If the wrong bed is used, the resonant frequency can have a fatal influence on the precision machining and increase the defective rate of precision machined parts such as semiconductor parts. In this paper, vibration characteristics were evaluated through static load and resonance frequency analysis of automatic lathe bed. As a result, the maximum stress was 14.52 MPa, the maximum deformation amount was $12.15{\mu}m$, and the natural frequency was 189.43 Hz. The resonance frequency was calculated as 500 Hz, and the stability was confirmed by being in the range of 200 Hz or more, which is the processing condition.

A comparative study about community characters of Chinese Fujian Tulou and Korean Yangdong Village (푸젠 토루와 양동마을 커뮤니티 특성 비교 연구)

  • Lee, yeong sik;Chung, Mi Sun
    • Korea Science and Art Forum
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    • v.35
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    • pp.315-329
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    • 2018
  • This study starts from the points of comparative analysis about cultural differences of old traditional communities. Those communities are Chinese Fujian tulou and Historic Villages of Korea Hahoe and Yangdong. (i..e.Yangdong ) I worked field study on traditional communities in two countries and literiture study. I have analysied on characteristics of Fujian tulou and Yangdong. and compared Fujian tulou's characteristics with traditional characteristics of Yangdong The results of this study are as follows. First, Fujian tulou was built according to the nature, and they have worshipped their anscestor and they are the blood relative community. Second, Yangdong was built according to the nature, too. But Yangdong has been completely reflected the confusianal societies' classes.( ex : yangban and slave ) Yangdong has the characteristics on confusianal community. From the results of this study, I think that further study is needed about non- physical cultural factors which were served to maintain the traditional community like governance, self doctrine and community rules.

Physicochemical and Sensory Characteristics of Green Tea Dasik Processing with Varied Levels of Oligosaccharide (올리고당의 첨가 수준을 달리한 녹차다식의 이화학적 관능적 특성 연구)

  • Kim, Hee-Sun;Chung, Han-Hee;Lee, Yong-Sik;Kim, Hae-Young
    • Journal of the Korean Society of Food Culture
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    • v.22 no.5
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    • pp.615-620
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    • 2007
  • Physicochemical and sensory characteristics of the green tea dasik varying the added value of oligosaccharide were investigated and the products were surveyed by elementary school students regarding the acceptability. Protein and ash contents were significantly higher and fat contents were significanlty lower in the samples with oligosaccharides compared to those in commercial ones(p<0.05). Commercial samples had significantly higher values in all of the textural characteristics using textural analyzer compared to those of the developed dasik sample groups. In analytical sensory evaluation, varying the amount of oligosaccharide, commercial samples had significantly higher values of sweetness, hardness, and cohesiveness and lower values of savory aroma and falvor compared to those of developed dasik(p<0.05). Savory aroma and flavor were highly negatively correlated with textural hardness, springiness, chewiness, gumminess, and cohesiveness(p<0.01), while sensory sweetness and hardness were significantly positively correlated with textural springiness(p<0.05), chewiness, gumminess, and cohesiveness(p<0.01). When surveying elementary school students regarding the acceptability of green tea dasik and commercial samples, green tea dasik 2 was the most preferred with significance in color. Regarding aroma, green tea dasik 1 received the highest acceptability (p<0.05). In the flavor, both dasik 1 and 2 received higher score than those of the commercial dasik. In overall acceptability, both green tea dasik 1 and 2 were preferred to the commercially sold ones with significance(p<0.05).

Physicochemical and Sensory Characteristics of Sponge Cake System Prepared with Domestic and Imported Wheat Flour (국내산과 수입 밀가루로 제조한 스폰지 케익의 이화학적 및 관능적 특성)

  • Oh, Myung-Suk;Kim, Hye-Young L.;Lee, Yong-Sik;Kim, Hee-Sun
    • Journal of the Korean Society of Food Culture
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    • v.22 no.6
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    • pp.813-819
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    • 2007
  • Physicochemical and sensory properties of sponge cakes using 2 kinds of domestic wheat flour(white flour, whole wheat flour) and imported cake flour were investigated. In the proximate analysis, white flour had higher contents of water and protein compared with those of imported flour. Whole wheat flour had the highest contents of protein, lipid and ash. Regarding the batter, imported flour sample showed lower specific gravity and higher viscosity than those of domestic flour sample, implying that there was more air incorporation and higher batter stability. As a result, imported flour batter produced larger cake compared to that of domestic flour batter. But indexes of symmetry and uniformity showed no significant difference among the samples. In textural analysis using rheometer, cakes with imported flour were softer compared with that with domestic flour. In gumminess and brittleness, cakes with domestic white flour showed the highest value while that with the imported flour showed the lowest value. For the color measurements of cake crumb, no significant difference in DE was found among the samples. Regarding the cross-sections of the cake observed using SEM, imported flour produced cake with smaller and more even air cells compared to that with the domestic flour cake. In sensory evaluation, cakes with the domestic white flour showed the highest moistness value. But there was no significant difference in springiness, firmness, adhesiveness and ease of swallow among the samples. In conclusion, cakes with domestic white flour and whole wheat flour were as good as that with imported cake flour for the sponge cake preparation.

Characteristics of Cochlodinium polykrikoides Bloom in Southeast Coastal Waters of Korea, 2008 (2008년 남해동부해역의 Cochlodinium polykrikoides 적조발생 특성)

  • Lim, Weol-Ae;Lee, Young-Sik;Park, Jong-Gyu
    • The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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    • v.14 no.3
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    • pp.155-162
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    • 2009
  • To characterize the initiation, propagation and termination of Cochlodinium polykrikoides blooms in the southeast coastal waters of Korea, 2008, we analyzed the data set of phytoplankton composition, physical and chemical water properties, and meterological data. C. polykrikoides bloom in 2008 were long lasting and restricted to the coastal area with a low density. Our results indicate that C. polykrikoides blooms were affected by the atypical cold waters occurring in east-south coastal water in the early July. The cold water masses probably protected the free living cells of C. polykrikoides from entering into the coastal area from offshore waters as a pelagic seed population. The low density blooms of small scale established possibly by the germination of C. polykrikoides cyst in shallow coastal bottom could have not spread over because of the weak wind and low nutrient concentrations caused by severe drought in July and September.

Psychopathology, Temperament, and Character Factors of Adults with Childhood Attention-Deficit Hyperactivity Symptoms (아동기에 주의력결핍 과잉행동증상을 경험한 성인의 정신병리와 기질 성격 요인)

  • Song, Yul-Mai;Lee, Kounseok;Han, Doug Hyun;Lee, Young Sik;Min, Kyung Joon;Park, Jin Young;Kim, Jun Won
    • Journal of the Korean Academy of Child and Adolescent Psychiatry
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    • v.24 no.4
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    • pp.191-198
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    • 2013
  • Objectives : The objective of this study is to find out the differences in psychopathology, temperament, and character factors between young adults with and without childhood attention-deficit hyperactivity disorder (ADHD) symptoms. Methods : The subjects consisted of 314 university students (male=72, female=242) in Gongju. They were divided into childhood ADHD group (N=54) and normal group (N=260) to the Wender-Utah Rating Scale. Participants were assessed using Korean Adult ADHD Scale, Beck Depression Inventory-II, Beck Anxiety Inventory, Kimberly Young's Internet Addiction Test, Barratt Impulsiveness Scale, Paranoia Scale, Korean-Schizotypal Ambivalence Scale, Lubben Social Network Scale, and Temperament and Character Inventory-Revised. Descriptive statistics, t-test, chi-square, spearman correlation, and stepwise multiple regression were applied to analyze the data. Results : Participants with childhood ADHD symptoms had high level of adult ADHD symptoms (p<.001), impulsiveness (p=.001), depression (p<.001), anxiety (p<.001), internet addiction (p<.001), paranoia tendency (p<.001) and low level of selfesteem (p<.001) compared to normal group. Self-directedness (p<.001) was lower, Harm avoidance (p=.001) and Self-transcendence (p=.029) were higher in the childhood ADHD group. In correlation and stepwise multiple regression, childhood ADHD symptoms were significantly associated with cooperativeness (r=-0.515 and ${\beta}$=-0.547, p<.001 respectively). Conclusion : This result showed that young adults with childhood ADHD symptoms had various forms of psychopathology and childhood ADHD symptoms were influenced by character such as cooperativeness. Therefore, more thorough evaluation regarding childhood ADHD symptoms is needed.

PRELIMINARY STUDY FOR ADHD TREATMENT GUIDELINE (ADHD 최적치료 지침을 위한 예비연구)

  • Kim, Eun-Young;Ra, Chul;Lee, Young-Sik
    • Journal of the Korean Academy of Child and Adolescent Psychiatry
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    • v.13 no.1
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    • pp.129-138
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    • 2002
  • Objectives:In order to treatment guideline of ADHD, present clinical practise of child psychiatrists and their opinion of optimal intervention were evaluated. Methods:Structured questionnaire items about diagnostic workup, drug choice of 5 different situations according to different co-morbid disorders, and non - pharmacological treatment were applied to 32 child psychiatrists working at university and general hospital. we compared the data with Texas Algorithm Project guideline. Results:(1) Intelligence Test, Sentence Completion Test, sustained attention test, and Conner's questionnaire were the basic routine test that must be performed. (2) Main trend of medication in this study was not different from TAP guideline. (3) In case of co-morbid tic disorder, first recommending drug is still psychostimulant in the TAP guideline. But in this study initial psychostimulant prescription was not main trend. (4) In case of MPH non-response co-morbid disruptive behavior disorder, MPH medication combined with other drug were more common than switching to other drug as suggested the TAP guidelines. (5) In non-pharmacological treatment, most child psychiatrists reported the importance of parent management. Conclusion:There were some difference in medication trend in this study compared with TAP guideline. Further study and conference are needed for experts consensus in Korea.

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