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이종 입체영상 카메라의 피사계심도 일치화 (DOF Correction of Heterogeneous Stereoscopic Cameras)

  • 최성인;박순용
    • 전자공학회논문지
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    • 제51권7호
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    • pp.169-179
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    • 2014
  • 본 논문에서는 서로 다른 광학적 특성을 가지는 3차원 카메라의 내부 변수 값을 자동으로 결정하여 스테레오 영상의 심도를 일치시키는 기술을 제안한다. 3차원 카메라에서 획득한 스테레오 영상에서 물체의 크기가 다르거나 심도의 차이가 큰 경우에 사람의 눈은 시각적 피로감을 느끼게 된다. 획득된 좌, 우 영상에서 물체의 크기가 동일하도록 카메라의 줌(zoom)을 LUT(Look Up Table)을 이용하여 일치시키고 피사체까지의 거리에 따라 전방심도와 후방심도의 범위를 결정한다. 이들을 이용하여 렌즈의 F-값을 결정하고 카메라의 광학 특성값을 자동으로 조절함으로써 스테레오 영상의 심도를 일치시킨다. 주-부 방식의 3차원 카메라와 GUI 소프트웨어를 통한 실험을 통하여 제안한 방법으로 스테레오 영상의 심도를 자동으로 일치시킬 수 있음을 보였다.

Newton 차분법을 이용한 개선된 디인터레이싱 연구 (A study on Improved De-Interlacing Applying Newton Difference Interpolation)

  • 백경훈
    • 문화기술의 융합
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    • 제6권1호
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    • pp.449-454
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    • 2020
  • 본 논문에서는 하나의 필드만을 사용하여 비월 주사 영상을 순차 주사 영상으로 변환하는 개선된 디인터레이싱 방법을 제안한다. 먼저, 구하고자 하는 화소의 위와 아래 각각 5개 화소를 이용하여 세분화된 화소 사이의 값들을 Newton의 전향차분과 후향차분을 이용하여 구한다. 이렇게 얻어진 화소 사이의 값과 5개의 알려진 화소값들을 이용하여 구하고자하는 화소를 중심으로 위와 아래화소의 방향을 세분화하여 각각의 상관관계를 구한다. 구하고자 하는 화소에서의 에지의 방향성은 위와 아래 상관관계가 가장 최소가 되는 방향으로 예측한다. 구하고자 하는 화소값 결정은 예측된 방향에 따라 위와 아래 화소값의 평균값으로 결정한다. 모의실험 결과 기존의 제시된 여러 디인터레이싱 방법에 비해 엣지에서의 주관적 화질이 개선되었으며 또한 객관적 화질에 있어서 정량적으로 PSNR 계산결과 0.2~0.3dB정도의 화질개선이 이루어졌다.

由 《漂海録》 看中国文化传承的分析 (Thorough Analysis of Chinese Cultural Heritage Based on Pyohaerok)

  • 최창원
    • 산업진흥연구
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    • 제1권2호
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    • pp.121-128
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    • 2016
  • Cultural heritage means a great lot to a nation's social system and its people's behavior consciousness and plays an important role in its self-development and improvement. It is essential for a nation's self-education and renewal. Improper cultural heritage will be disastrous because it may fall a nation into a loss of terrible chaos. Only the proper cultural heritage can make it always self-awaking, self-correcting and remaining vital in life. This paper, from the perspective of Choi Bu's Pyohaerok, makes a thorough analysis of the unbalance heritage of Chinese ancient culture for thousands of years. For example, many fine traditions gradually vanished in our actual life or only take half their life in heritage nowadays, such as our ancient broad and profound Confucian etiquette, ancient exquisite brocade art and architecture, ancient advanced ship-building technology and many other advanced numerous technological inventions; however, too much unwanted cultural rubbish keeps constant prevailing and takes repeated successions in the life, such as the heavy-form-and-light-content management mode, borrowing power to do evil, neglecting technological inventions long time and generally believing in ghost theory,etc.. This paper mainly focuses on the partial successions of the bad cultural heritage and its bad influence on the country, and concludes that it is just that that makes the country more and more backward. Therefore, the paper makes some pondering over these issues and proposes some related ideas of country-building to attract others participation to deal with them.

주의력결핍 과잉행동장애 아동청소년의 Korean Wechsler Intelligence Scale for Children-Fourth Edition 프로파일 : 후향적 의무기록 분석 (Korean Wechsler Intelligence Scale for Children-Fourth Edition Profiles in Child and Adolescent with Attention-Deficit Hyperactivity Disorder : Retrospective Study)

  • 고민경;노은아;김효원
    • Journal of the Korean Academy of Child and Adolescent Psychiatry
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    • 제26권3호
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    • pp.183-189
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    • 2015
  • Objectives : The aim of this study was to investigate Korean Wechsler Intelligence profiles and specific abilities related to attention problem of children with attention-deficit hyperactivity disorder (ADHD). Methods : The Korean Wechsler Intelligence Scale for Children-fourth edition (K-WISC-IV) and Advanced Test of Attention (ATA) were administered to 91 children and adolescents (age $8.5{\pm}2.6$ years, 73 boys) with ADHD. Pearson correlation and independent t-tests were used. Results : The means of Working Memory Index (WMI) and Processing Speed Index (PSI) showed a score of low average in K-WISC-IV. WMI scores for the K-WISC-IV showed clinically significant correlations with omission errors, commission errors, and response time variability on auditory ATA. PSI scores also showed significant correlations with response time and variability on visual ATA. In addition, significantly lower digit span backward scores were observed in hyperactive-impulsive/combined subtypes compared to inattentive subtype (t=3.60, p<.001). Conclusion : Children with ADHD showed significantly lower scores in WMI and PSI which were clinically correlated with ATA scores, and hyperactive-impulsive/combined subtypes showed poorer working memory functions in WMI. Follow-up studies are proposed.

경기도 농촌형 초등학교 어린이 대상 건강교육 프로그램의 효과 평가 (Effects of a Health Education Program for Elementary School Children in Gyeonggi-do Rural Area)

  • 임재연;나혜복
    • 대한지역사회영양학회지
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    • 제16권1호
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    • pp.1-13
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    • 2011
  • The purpose of this study was to implement and evaluate the health education program for elementary school children. The program consisted of nutritional education and physical exercise. The subjects composed of 89 school children, first through sixth grade (n = 100), who had completed ten weeks of health education program from April through July 2010. Pre-post intervention design was used to evaluate the program effectiveness. After completing health education program, the number of overweight subjects decreased (boys 13 to 11 and girls 11 to 9) and the number of obese subjects decreased from 5 to 4 for boys and 4 to 2 for girls The number of sit-ups significantly increased in both 1-2 grade girls and 3-4 grade girls. Backward trunk extension of 1-2 grade girls also significantly increased (p < 0.05). The level of serum total cholesterol decreased from 171.8 mg/dL to 153.5 mg/dL (p < 0.001). Hypercholesterolemia (above 239 mg/dL), hyperLDLcholesterolemia (above 175 mg/dL) and low level hemoglobin subjects changed to normal levels. Total score of nutrition knowledge increased from 5.9 to 6.1 (p < 0.05), percentage of perception answers increased significantly in 5 out of 10 items and percentage of correct answers increased significantly in 6 out of 10 items (p < 0.05). Three food habits improved, including, "having breakfast", "having diverse foods" and "having vegetables per meal" (p < 0.05). Two self-efficacy items improved significantly, including, "having meals slowly", "having exercise instead of watching TV or computer" (p < 0.05). These results suggest that health education program for elementary school children including nutritional education and physical exercise may be effective to improve their anthropometric characteristics, physical fitness, hyperlipidemia, nutrition knowledge, food habits and self-efficacy.

Designing Hypothesis of 2-Substituted-N-[4-(1-methyl-4,5-diphenyl-1H-imidazole-2-yl)phenyl] Acetamide Analogs as Anticancer Agents: QSAR Approach

  • Bedadurge, Ajay B.;Shaikh, Anwar R.
    • 대한화학회지
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    • 제57권6호
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    • pp.744-754
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    • 2013
  • Quantitative structure-activity relationship (QSAR) analysis for recently synthesized imidazole-(benz)azole and imidazole - piperazine derivatives was studied for their anticancer activities against breast (MCF-7) cell lines. The statistically significant 2D-QSAR models ($r^2=0.8901$; $q^2=0.8130$; F test = 36.4635; $r^2$ se = 0.1696; $q^2$ se = 0.12212; pred_$r^2=0.4229$; pred_$r^2$ se = 0.4606 and $r^2=0.8763$; $q^2=0.7617$; F test = 31.8737; $r^2$ se = 0.1951; $q^2$ se = 0.2708; pred_$r^2=0.4386$; pred_$r^2$ se = 0.3950) were developed using molecular design suite (VLifeMDS 4.2). The study was performed with 18 compounds (data set) using random selection and manual selection methods used for the division of the data set into training and test set. Multiple linear regression (MLR) methodology with stepwise (SW) forward-backward variable selection method was used for building the QSAR models. The results of the 2D-QSAR models were further compared with 3D-QSAR models generated by kNN-MFA, (k-Nearest Neighbor Molecular Field Analysis) investigating the substitutional requirements for the favorable anticancer activity. The results derived may be useful in further designing novel imidazole-(benz)azole and imidazole-piperazine derivatives against breast (MCF-7) cell lines prior to synthesis.

Finite element modeling technique for predicting mechanical behaviors on mandible bone during mastication

  • Kim, Hee-Sun;Park, Jae-Yong;Kim, Na-Eun;Shin, Yeong-Soo;Park, Ji-Man;Chun, Youn-Sic
    • The Journal of Advanced Prosthodontics
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    • 제4권4호
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    • pp.218-226
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    • 2012
  • PURPOSE. The purpose of this study was to propose finite element (FE) modeling methods for predicting stress distributions on teeth and mandible under chewing action. MATERIALS AND METHODS. For FE model generation, CT images of skull were translated into 3D FE models, and static analysis was performed considering linear material behaviors and nonlinear geometrical effect. To find out proper boundary and loading conditions, parametric studies were performed with various areas and directions of restraints and loading. The loading directions are prescribed to be same as direction of masseter muscle, which was referred from anatomy chart and CT image. From the analysis, strain and stress distributions of teeth and mandible were obtained and compared with experimental data for model validation. RESULTS. As a result of FE analysis, the optimized boundary condition was chosen such that 8 teeth were fixed in all directions and condyloid process was fixed in all directions except for forward and backward directions. Also, fixing a part of mandible in a lateral direction, where medial pterygoid muscle was attached, gave the more proper analytical results. Loading was prescribed in a same direction as masseter muscle. The tendency of strain distributions between the teeth predicted from the proposed model were compared with experimental results and showed good agreements. CONCLUSION. This study proposes cost efficient FE modeling method for predicting stress distributions on teeth and mandible under chewing action. The proposed modeling method is validated with experimental data and can further be used to evaluate structural safety of dental prosthesis.

초기 혼합치열기에서의 Face mask의 임상적 적용 (FACE MASK THERAPY IN EARLY MIXED DENTION)

  • 이창주;김종수;권순원
    • 대한소아치과학회지
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    • 제28권4호
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    • pp.643-648
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    • 2001
  • III급 부정교합은 전치가 수평적으로 반대로 물리는 양상 때문에 치과의사뿐만 아니라 일반인에 의해서도 쉽게 발견되므로 비교적 조기에 치과를 찾는 빈도가 높다. 이러한 III급 부정교합 치료 시에 치과의사들이 사용할 수 있는 방법은 여러 가지가 있을 수 있으며 그 중 정형적 Face mask는 III급 부정교합에 기여하는 모든 요소 즉, 상악골 후퇴, 하악전돌, 낮은 전방하안면고경에 전반적으로 영향을 미치기 때문에 가장 폭넓게 적용가능하고 가장 짧은 기간에 극적인 결과를 나타내기 때문에 대부분의 발육중인 III급 증례에 적용될 수 있다. 이에 본원에 내원한 III급 부정교합 환아에서 Face mask를 적응함으로써 다음과 같은 결과를 얻었다. 1. 전치부 반대 교합이 상악골의 전방이동 하악골의 후하방 회전에 의해 해소되었다. 2. 경조직, 연조직에서 안모의 개선이 나타났다.

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상악 제 2 대구치 발거에 의한 교정치료의 효과 (A STUDY ON TREATMENT EFFECTS OF MAXILLARY SECOND MOLAR EXTRACTION CASES)

  • 정규림;박영국;이영준;이성희;김성훈
    • 구강회복응용과학지
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    • 제16권2호
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    • pp.93-104
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    • 2000
  • Orthodontic treatment in conjunction with second-molar extraction has been a controversial issue among orthodontists over many decades. The aim of this study was to investigate the treatment effects of upper second molar extraction cases. The sample included 19 upper second molar extraction orthodontic cases(ten Angle's Class I's and nine Class II's, average age=13Y 6M) cared at Kyung-Hee University Department of Orthodontics. Lateral cephalometric radiographs were taken before and immediately after treatment. Seventy-nine points were digitized on each cephalogram and 38 cephalometric parameters were computed comprising 22 angular measurements, 13 linear measurements, and 3 facial proportions. The data obtained from each malocclusion group were analyzed by paired t-test. The statistical results disclosed that there was no significant change in skeletal pattern after treatment except for that accountable by growth while there was statistically significant change in dentoalveolar and soft tissue patterns. There were no significant changes in Bjork sum, posterior facial height /anterior facial height and lower anterior facial height /anterior facial height. No significant changes in anteroposterior position of maxilla and palatal plane were manifested. Although facial axis and lower facial height was slightly increased and the mandible was rotated backward and downward, there was no remarkable change in the mandibular plane. There were statistically significant changes in distal movement of upper first molar, molar key correction and overjet reduction while there was no change in the occlusal plane. The upper lip was slightly retracted simultaneously with slight increase in nasolabial angle. These results signify that distalization of upper dentition with the second molar extraction does change occlusal relationship without gross modifications in the craniofacial skeletal configurationson. Henceforth the second molar extracted would be recommended to treat severe anterior crowding and protrusion with minor skeletal discrepancy.

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고진공 터보 분자펌프용 자기베어링 시스템의 디지털 선형 제어시스템 (Digital Linear Control System for a Magnetic Bearing System of a High Vacuum Turbomolecular Pump)

  • 노승국;경진호;박종권;남우호;고득용
    • 한국진공학회지
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    • 제19권4호
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    • pp.256-264
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    • 2010
  • 본 논문에서는 고진공용 터보분자펌프의 비접촉 고속회전을 위한 자기베어링 시스템의 디지털 제어시스템의 설계에 대하여 소개하였으며, 실례로 800 l/s급의 고진공 펌프에 대하여 축 유연모드의 후방향 위험속도를 넘는 최대 40,000 rpm까지의 회전실험 결과를 나타내었다. 제안된 제어시스템은 기본적으로 PID 기반의 직접궤환 제어기와 자이로스코픽 모멘트 효과를 제어하기 위한 교차궤환기, 유연모우드 감쇄를 위한 리드필터와 동기진동 저감을 위한 노치필터 등으로 구성되어 있으며, 이러한 제어기는 자기부상형 터보분자펌프 외에 고속 플라이휠과 같은 자기베어링에 적용될 수 있다.