• 제목/요약/키워드: Facial unit

검색결과 98건 처리시간 0.027초

PCA 표상을 이용한 강인한 얼굴 표정 인식 (Robust Facial Expression Recognition using PCA Representation)

  • 신영숙
    • 인지과학
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    • 제16권4호
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    • pp.323-331
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    • 2005
  • 본 논문은 조명 변화에 강인하며 중립 표정과 같은 표정 측정의 기준이 되는 단서 없이 다양한 내적상태 안에서 얼굴표정을 인식할 수 있는 개선된 시스템을 제안한다. 표정정보를 추출하기 위한 전처리 작업으로, 백색화(whitening) 단계가 적용되었다. 백색화 단계는 영상데이터들의 평균값이 0이며 단위분산 값으로 균일한 분포를 갖도록 하여 조명 변화에 대한 민감도를 줄인다. 백색화 단계 수행 후 제 1 주성분이 제외된 나머지 주성분들로 이루어진 PCA표상을 표정정보로 사용함으로써 중립 표정에 대한 단서 없이 얼굴표정의 특징추출을 가능하게 한다. 본 실험 결과는 또한 83개의 내적상태와 일치되는 다양한 얼굴표정들에서 임의로 선택된 표정영상들을 내적상태의 차원모델에 기반한 얼굴표정 인식을 수행함으로써 다양하고 자연스런 얼굴 표정 인식을 가능하게 하였다.

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얼굴정렬과 AdaBoost를 이용한 얼굴 표정 인식 (Facial Expression Recognition using Face Alignment and AdaBoost)

  • 정경중;최재식;장길진
    • 전자공학회논문지
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    • 제51권11호
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    • pp.193-201
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    • 2014
  • 본 논문에서는 얼굴영상에 나타난 사람의 표정을 인식하기 위해 얼굴검출, 얼굴정렬, 얼굴단위 추출, 그리고 AdaBoost를 이용한 학습 방법과 효과적인 인식방법을 제안한다. 입력영상에서 얼굴 영역을 찾기 위해서 얼굴검출을 수행하고, 검출된 얼굴영상에 대하여 학습된 얼굴모델과 정렬(Face Alignment)을 수행한 후, 얼굴의 표정을 나타내는 단위요소(Facial Units)들을 추출한다. 본 논문에서 제안하는 얼굴 단위요소들을 표정을 표현하기 위한 기본적인 액션유닛(AU, Action Units)의 하위집합으로 눈썹, 눈, 코, 입 부분으로 나눠지며, 이러한 액션유닛에 대하여 AdaBoost 학습을 수행하여 표정을 인식한다. 얼굴유닛은 얼굴표정을 더욱 효율적으로 표현할 수 있고 학습 및 테스트에서 동작하는 시간을 줄여주기 때문에 실시간 응용분야에 적용하기 적합하다. 실험결과, 제안하는 표정인식 시스템은 실시간 환경에서 90% 이상의 우수한 성능을 보여준다.

가토의 안면-두피 피판 동종이식을 위한 실험용 모델 연구 (An Experimental Study about flap Viability after Harvesting of the Composite Face/Scalp flap for Allotransplantation in Rabbit Model)

  • 서영민;정승문
    • Archives of Reconstructive Microsurgery
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    • 제14권2호
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    • pp.95-104
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    • 2005
  • The aim of this study was to investigate the major vascular system to supply flap, flap survival rate and complications after flap elevation in order to evaluate possibility of the vascularized face/scalp allotransplantation. Forty New Zealand white rabbits were divided into two groups: control group and experimental group. Individuals of control group had a face/scalp composite unit which was composed of skin, subcutaneous tissue and platysma muscle, supplying by bilateral facial artery, temporal artery and auricular artery and draining by external jugular vein. After a flap was elevated, bilateral facial artery, temporal artery and auricular artery were ligated. On the other hand, those of experimental group had the same composite unit as control group with bilateral facial artery, temporal artery and auricular artery being not ligated. We had measured survival area of flaps of the sixteen individuals survived for four weeks in the control group and fourteen in the experimental group by Grid method. The mean survival durations of the flap were 3.7days in the control group, 20.0days in the experimental group. The significant differences in the mean survival durations and survival rate at the 28days were found between the control and experimental group (p<0.05). Mean values about the survival area's fractions of all were $1.3{\pm}4.%$ in the control group and $63.1{\pm}4.8%$ in the experimental group. Those of experimental group was significantly higher than control group statistically (p<0.05). The composite face/scalp flap which we have elevated, supplied by bilateral facial artery, temporal artery, auricular artery and drained by external jugular vein has flap viability enough to be transplanted after its elevation.

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Transmasseteric antero-parotid facelift approach for open reduction and internal fixation of condylar fractures

  • Choi, Moon-Gi
    • Journal of the Korean Association of Oral and Maxillofacial Surgeons
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    • 제41권3호
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    • pp.149-155
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    • 2015
  • Surgical approaches to the condylar fracture include intraoral, preauricular, submandibular, and retromandibular approaches. Each approach has its own advantages and disadvantages. When a patient needs esthetic results and an intraoral approach is not feasible, the transmasseteric antero-parotid facelift approach is considered. This approach permits direct exposure and allow the surgeon to fixate the fractured unit tangentially. Tangential fixation is critical to osteosynthesis. Disadvantages of the transmasseteric antero-parotid facelift approach include damage to the facial nerve and a longer operation time. However, after the initial learning curve, facial nerve damage can be avoided and operation time may decrease. We report three cases of subcondylar fractures that were treated with a transmasseteric antero-parotid facelift approach. Among these, two cases had trivial complications that were easily overcome. Instead of dissecting through the parotid gland parenchyma, the transmasseteric antero-parotid facelift approach uses transmasseteric dissection and reduces facial nerve damage more than the retromandibular transparotid approach. The esthetic result is superior to that of other approaches.

Use of 1,064-nm Q-switched Neodymium:Yttrium-aluminum-garnet Laser Therapy Assisted with Diamond Particle Suspension and Gold Microparticle Application for Acne Vulgaris and Enlarged Facial Pores

  • Park, Hee Ung;Cho, Hangrae;Lee, Sang Ju;Cho, Han Kyoung
    • Medical Lasers
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    • 제10권4호
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    • pp.242-245
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    • 2021
  • Acne vulgaris is a common inflammatory skin disease of the pilose-baceous unit. It appears as lesions consisting of comedones, papules, pustules, and nodules of varying shapes and severity. In general, the first-line treatment for acne vulgaris includes topical and oral medication. Recently, various physical modalities have also been investigated. The use of laser therapy is steadily increasing because of its fewer side effects, short procedure time, and rapid results. In particular, laser therapy assisted with carbon suspension application is effective for acne vulgaris but may sometimes result in discomfort due to odor and dust formation during the procedure. Herein, we report that acne vulgaris and enlarged facial pores can be safely and effectively treated with laser therapy assisted with diamond particle suspension and gold microparticle application, which can address the discomfort caused by the carbon suspension application.

Prompt Tuning for Facial Action Unit Detection in the Wild

  • ;;김애라;김수형
    • 한국정보처리학회:학술대회논문집
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    • 한국정보처리학회 2023년도 춘계학술발표대회
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    • pp.732-734
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    • 2023
  • Facial Action Units Detection (FAUs) problem focuses on identifying various detail units expressing on the human face, as defined by the Facial Action Coding System, which constitutes a fine-grained classification problem. This is a challenging task in computer vision. In this study, we propose a Prompt Tuning approach to address this problem, involving a 2-step training process. Our method demonstrates its effectiveness on the Affective in the Wild dataset, surpassing other existing methods in terms of both accuracy and efficiency.

FACS와 AAM을 이용한 Bayesian Network 기반 얼굴 표정 인식 시스템 개발 (Development of Facial Expression Recognition System based on Bayesian Network using FACS and AAM)

  • 고광은;심귀보
    • 한국지능시스템학회논문지
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    • 제19권4호
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    • pp.562-567
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    • 2009
  • 얼굴 표정은 사람의 감정을 전달하는 핵심 메커니즘으로 이를 적절하게 활용할 경우 Robotics의 HRI(Human Robot Interface)와 같은 Human Computer Interaction에서 큰 역할을 수행할 수 있다. 이는 HCI(Human Computing Interface)에서 사용자의 감정 상태에 대응되는 다양한 반응을 유도할 수 있으며, 이를 통해 사람의 감정을 통해 로봇과 같은 서비스 에이전트가 사용자에게 제공할 적절한 서비스를 추론할 수 있도록 하는 핵심요소가 된다. 본 논문에서는 얼굴표정에서의 감정표현을 인식하기 위한 방법으로 FACS(Facial Action Coding System)와 AAM(Active Appearance Model)을 이용한 특징 추출과 Bayesian Network 기반 표정 추론 기법이 융합된 얼굴표정 인식 시스템의 개발에 대한 내용을 제시한다.

A study on the fracture strength of collarless metal-ceramic fixed partial dentures

  • Yoon, Jong-Wook;Kim, Sung-Hun;Lee, Jai-Bong;Han, Jung-Suk;Yang, Jae-Ho
    • The Journal of Advanced Prosthodontics
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    • 제2권4호
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    • pp.134-141
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    • 2010
  • PURPOSE. The objective of this study was to evaluate fracture strength of collarless metal-ceramic FPDs according to their metal coping designs. MATERIALS AND METHODS. Four different facial margin design groups were investigated. Group A was a coping with a thin facial metal collar, group B was a collarless coping with its facial metal to the shoulder, group C was a collarless coping with its facial metal 1 mm short of the shoulder, and group D was a collarless coping with its facial metal 2 mm short of the shoulder. Fifteen 3-unit collarless metal-ceramic FPDs were fabricated in each group. Finished FPDs were cemented to PBT (Polybutylene terephthalate) dies with resin cement. The fracture strength test was carried out using universal testing machine (Instron 4465, Instron Co., Norwood MA, USA) at a cross head speed of 0.5 mm/min. Aluminum foil folded to about 1 mm of thickness was inserted between the plunger tip and the incisal edge of the pontic. Vertical load was applied until catastrophic porcelain fracture occurred. RESULTS. The greater the bulk of unsupported facial shoulder porcelain was, the lower the fracture strength became. However, there were no significant differences between experimental groups (P > .05). CONCLUSION. All groups of collarless metal-ceramic FPDs had higher fracture strength than maximum incisive biting force. Modified collarless metal-ceramic FPD can be an alternative to all-ceramic FPDs in clinical situations.

혐오자극에 대한 정서조절전략이 얼굴표정 및 정서경험에 미치는 영향 (The Effects of the Emotion Regulation Strategy to the Disgust Stimulus on Facial Expression and Emotional Experience)

  • 장성리;이장한
    • 한국심리학회지ㆍ건강
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    • 제15권3호
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    • pp.483-498
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    • 2010
  • 본 연구는 혐오정서 유발자극에 대한 선행사건초점 조절전략과 반응초점 조절전략이 얼굴표정 및 정서경험에 미치는 영향을 알아보고자 하였다. 연구는 여자 대학생 50명을 대상으로 실시되었고, 참여자들이 혐오정서 유발동영상을 시청할 때 서로 다른 정서조절전략(정서 표현, 표현 억제, 인지적 재평가, 표현 불일치)을 사용하도록 하여 얼굴표정과 정서경험을 측정하였다. 분석결과, 정서 표현집단에서 혐오표현단위의 빈도가 가장 높았고 표현 불일치, 인지적 재평가, 표현 억제집단의 순으로 빈도가 높게 나타났다. 그리고 실제 경험한 정서를 반영하는 얼굴 윗부분에서 인지적 재평가집단의 혐오관련표현단위의 빈도가 정서 표현집단과 표현 불일치집단보다 낮게 나타났다. 자기보고식 정서 상태 측정결과, 표현 불일치집단에서 가장 많이 긍정정서가 감소한 반면, 인지적 재평가집단에서는 긍정정서가 증가하는 경향을 보였다. 본 연구는 정서조절전략이 얼굴표정 및 정서경험에 미친 영향을 통해 인지적 재평가전략이 가장 기능적인 정서조절전략임을 확인하였다.

Holographic Interferometry를 이용한 하악 구치부 도재소부 전장관용 금속 구조물의 굴곡성향에 대한 연구 (FLEXION EFFECTS OF HEAT TREATMENT AND POST-SOLDRING OF CERAMO-METAL FIXED PARTIAL DENTURE FRAMEWORKS USING HOLOGRAPHIC INTERFEROMETRY)

  • 최진웅;우이형;최부병
    • 대한치과보철학회지
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    • 제34권4호
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    • pp.869-902
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    • 1996
  • Flexion of a metal/ceramic fixed partial denture(EPD) frameworks under function can cause fracture of porcelain or deterioration of the cement seal. This study evaluated the flexion characteristics of three-unit mandibular FPD frameworks, repacing the second pre-molar under compressive load(200g, 400g). Testing was accompished with real-time holographic interferometry, using 6 porcelain fused-to metal frameworks. Tested alloys were non-precious alloy(Heracles, Holland), semi-precious alloy(Degudent U, Germany) and precious alloy(Degudent H, Germany). Changes of the fringe patterns according to the heat treatment(porcelain firing cycle), various loads(200g, 400g), occlusal forms(occlusal porcelain veneering, facial porcelain veneering), various alloys and post-soldering units were compared. Dental study model(Nissan dental products, Inc. D51DP-500A, Japan) and six 3-unit metal/ceramic fixed partial denture frameworks were used as experimental materials. 36 holograms were taken on fixed dental study model by using the 10mW He-Ne laser and real-time holographic interferometry. On the basis of this study, the following conclusions can be drawn : 1. In the frameworks for facial porcelain veneering, the semi-precious alloy framework was least deformed and precious alloy framework, non-precious alloy framework orderly before heat treatment, and the deformation was not shown great difference among three alloys after heat treatment and post-soldering. 2. In the frameworks for occlusal porcelain veneering, the precious alloy framework was greatest deformed and the deformation was not difference between semi-precious alloy framework and non-precious alloy framework before, after heat treatment, and the deformation was not shown great difference among three alloys after post soldering. 3. In the non-precious alloy frameworks for facial porcelain veneering and occlusal porcelain veneering, the deformation was greatly decreased after heat treatment and conversely increased after post-soldering. 4. In the semi-precious alloy framework for facial porcelain veneering, the deformation was not detectable after heat treatment and increased after post-solder. And in the frame-work for occlusal porcelain veneering, the deformation was slightly decreased after heat treatment and increased after post-soldering. 5. In the precious alloy framework for facial porcelain veneering, the deformation was greatly decreased after heat treatment and increased after post-soldering, And in the framework for occlusal porcelain veneering, the deformation was greatly decreased after heat treatment and decreased after post-soldering.

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