• 제목/요약/키워드: Central Moment

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자연치열에 설치한 pivot의 전후방 일치변화에 따른 하악의 moment에 관한 연구 (A STUDY ON THE MANDIBULAR MOMENTS ACCORDING TO ANTERO-POSTERIOR PLACEMENT OF PIVOT ON LOWER NATURAL DENTITION)

  • 이현식;박남수;최대균
    • 대한치과보철학회지
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    • 제31권3호
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    • pp.394-410
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    • 1993
  • This study was accomplished for appreciation of the mandibular moments according to antero- posterior movement of pivot placed on the lower natural dentition. For this study, 20 subjects(male, $21\sim30$ yrs., average age 24) in the category of normal occlusion were selected, and the intraoral Vitallium clutches were cast and fabricated for each subjects. A 2-dimension PSD(Position Sensitive Detector, Hamamatsu Photonics Co., Japan) was attached to maxillary clutch in a mode of three dimensional control and LED (Light Emit Diode, Hamamatsu Photonics Co., Japan) was set up on mandibular clutch. Both clutches were set into oral cavity of each subjects and adjusted. Then the subjects were allowed to intercuspated with maximal bite force while the pivoting ball in the mid-line moving from anterior toward posterior position. The displacement scales were recorded by CCD camera(Sony, CCD-TR-705) and VCR, The conclusions were as follows : 1. When the subject was allowed to bite the metal pivoting ball in the midline of lower dentition with maximal bite force voluntarily while moving from lower central incisor to canine, 1st premolar, End premolar, 1st molar and 2nd molar. The lever actions on the pivot were revealed in all subjects. The equilibrium of moment were revealed on the pivots of 1st premolar(14 subjects), End premolar(4 subjects), and canine(2 subjects) areas. 2. The changes of loading on the TMJ according to antero-posterior positional changes of metal pivoting ball were able to recognize as follow. Compression on the TMJ was increased when the pivot moves anteriorly from the equilibrium point, and tension on the TMJ was increased when posteriorly. 3. 13 subjects were recognized their habitual chewing sides(Rights, Left8), and 7 subjects were not. During maximal biting, mandible was displaced toward their habitual chewing sides on the metal pivoting ball in the frontal plane. 4. In cephalometric analysis, the average genial angle of 20 subjects was $116.75^{\circ}$ and the average mandibular body length was 79.77mm. The equilibrium points of mandibular moment were positioned more posteriorly in the subjects having larger Genial angle than in the smaller(p<0.05). Relationships among the angle between FH plane and occlusal plane, the angle between occlusal plane and mandibular plane , and mandibular body length were not significant(p>0.05).

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분석과 인물 창조 과정에 있어 '자발성'의 발현 원리와 적용 가능성에 관한 연구 - 보알의 방법론을 중심으로 - (Study on the Principle of a Performer's 'Spontaneity' and its Adaptability in a Process of Text Analysis and Creating a Character Focused on the Concept of Augusto Boal)

  • 손봉희
    • 한국엔터테인먼트산업학회논문지
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    • 제14권3호
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    • pp.277-284
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    • 2020
  • 본 논문의 목적은 공연자로서 배우의 몸을 통해 발현되는 '자발성'의 원리를 살펴보고 그 적용 가능성을 고찰하는 것이다. 이를 위해 동시대 배우들이 인물을 창조하기 위한 접근 및 훈련과정에서 흔히 직면하게 되는 문제점을 비판적인 관점에서 논의하고 그 대안으로 배우의 행동과 텍스트가 추구하는 본질적 기능과의 상호보완적 관계를 규명함으로써 연기예술의 토대를 이루는 핵심 원리를 재고하고자 한다. 본 연구에서 중점적으로 논의하는 자포라를 비롯한 마셜, 브루엘, 존스톤, 보알 등의 연기지도자들은 자발적 반응으로써 행동 과정의 중요성을 강조한다. 이들의 공통된 관점을 종합할 때 변화를 추구하고 이를 달성하고자하는 텍스트의 본질적 기능은 역설적으로 배우가 무대 위에서 필수적으로 수행해야 할 임무와 면밀하게 닿아있는 것이며, 이는 곧 예술가로서 배우 스스로가 선택하고 결정한 표현에 대한 책임과도 직결된 것이다. 본 논문은 이러한 과정을 바탕으로 분석과 행동의 상호보완적 관계 속에서 배우의 몸이 자발적 상태에 이르기 위한 접근 방법을 보알의 관점을 중심으로 살펴보고 그 실효성을 제언하고자 한다.

결합 적분방정식을 이용한 삼차원 임의형태 도체 구조물의 전자파 지연산란 해석 (Analysis of Transient Scattering from Arbitrarily Shaped Three-Dimensional Conducting Objects Using Combined Field Integral Equation)

  • 정백호
    • 대한전기학회논문지:전기물성ㆍ응용부문C
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    • 제51권11호
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    • pp.551-558
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    • 2002
  • A time-domain combined field integral equation (CFIE) is presented to obtain the transient scattering response from arbitrarily shaped three-dimensional conducting bodies. This formulation is based on a linear combination of the time-domain electric field integral equation (EFIE) with the magnetic field integral equation (MFIE). The time derivative of the magnetic vector potential in EFIE is approximated using a central finite difference approximation and the scalar potential is averaged over time. The time-domain CFIE approach produces results that are accurate and stable when solving for transient scattering responses from conducting objects. The incident spectrum of the field may contain frequency components, which correspond to the internal resonance of the structure. For the numerical solution, we consider both the explicit and implicit scheme and use two different kinds of Gaussian pulses, which may contain frequencies corresponding to the internal resonance. Numerical results for the EFIE, MFIE, and CFIE are presented and compared with those obtained from the inverse discrete Fourier transform (IDFT) of the frequency-domain CFIE solution.

The Application of Resettable Device to Semi-Active Tuned Mass Damper Building Systems for Multi-level Seismic Hazard Mitigation

  • Chey, Min-Ho
    • Architectural research
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    • 제14권3호
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    • pp.99-108
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    • 2012
  • An innovative multi-story Semi-Active Tuned Mass Damper (SATMD) building system is proposed to control seismic response of existing structures. The application of adding new stories as large tuned mass and semi-active (SA) resettable actuators as central features of the control scheme is derived. For the effective control of the structures, the optimal tuning parameters are considered for the large mass ratio, for which a previously proposed equation is used and the practical optimal stiffness is allocated to the actuator stiffness and rubber bearing stiffness. A two-degree-of freedom (2-DOF) model is adopted to verify the principal efficiency of the suggested structural control concept. The simulations for this study utilizes the three ground motions, from SAC project, having probability of exceedance of 50% in 50 years, 10% in 50 years, and 2% in 50 years for the Los Angeles region. 12-story moment resisting frames, which are modified as '12+2' and '12+4' story structures, are investigated to assess the viability and effectiveness of the system that aims to reduce the response of the buildings to earthquakes. The control ability of the SATMD scheme is compared to that of an uncontrolled and an ideal Passive Tuned Mass Damper (PTMD) building system. From the performance results of suggested '12+2' and '12+4' story retrofitting case studies, SATMD systems shows significant promise for application of structural control where extra stories might be added.

정팔면체 [Co(III)-$O_3N_3$], 정사면체 [M(II)-$O_2N_2$] 및 정사각형 [M(II)-$O_2N_2$] 형태 착물의 쌍극자모멘트의 계산 [M(II) = Ni(II) 또는 Cu(II)] (Calculation of the Dipole Moment for Octahedral [Co(III)-$O_3N_3$], Tetrahedral [M(II)-$O_2N_2$] and Square Planner [M(II)-$O_2N_2$] Type Complexes [M(II) = Ni(II) or Cu(II)])

  • 안상운
    • 대한화학회지
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    • 제22권5호
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    • pp.295-303
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    • 1978
  • 정팔면체[Co(III)-$O_3N_3$], 정사면체[M(II)-$O_2N_2$] 및 정사각형형[M(II)-$O_2N_2$]형태 착물의 쌍극자모멘트를 중심이온의 valence basis sets와 리간드의 single basis 궤도함수($2p_z$)를 사용하여 spherical harmonics의 전개방법에 의하여 계산하였다. 이들 착물에 대하여 계산한 쌍극자모멘트의 값이 실험치와 일치하였다.

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주 요소와 독립 요소 분석의 통합에 의한 얼굴 인식 (Face Recognition By Combining PCA and ICA)

  • 류재흥;김강철;임창균
    • 한국정보통신학회논문지
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    • 제10권4호
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    • pp.687-692
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    • 2006
  • 기존의 독립 요소 방법에 의한 얼굴인식에서는 주 요소 해석법으로 고유치 크기에 의해 특징을 추출하고 감소된 차원에서 특징 개선을 위한 독립 요소 해석법의 학습을 수행한다. 제거된 특징 공간 내에 필요한 요소가 있는 경우를 고려하지 못한 것이다. 새로운 방법은 독립 요소 해석에 의한 학습을 먼저 시행하고 분리된 데이터를 4차 중심 모멘트에 의한 축적 계수(cumulant)인 커토시스(kurtosis)의 절대값 크기에 의하여 특징을 추출한다. 하지만 독립 요소 방법은 효과적으로 노이즈를 제거하지 못한다. 두 방법의 결합효과는 주 요소 해석법을 노이즈 필터로 사용 할 때 극대화 될 수 있다. 즉 주 요소 해석법을 백색화와 노이즈 필터로 하고 독립 요소 해석법을 특징 추출 방법으로 사용하는 것이다. 실험 결과는 새로운 방법론이 기존의 방법론보다 우수함을 보여준다.

소형선박의 횡요방지 제어장치 연구 (A Study on the Anti-Rolling Control System of Small Ship)

  • 김시영;유재복;문철진
    • 수산해양교육연구
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    • 제11권2호
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    • pp.184-202
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    • 1999
  • The roll damping characteristics of the three models of a small fishing(3 ton class fishing vessel), such as the bare hull, hull with bilge keels, and hull with bilge keels and a central wing are investigated by the free roll and head waves tests in calm water in a towing tank with the various forward speeds, initial angles and OG's. The experimental results are compared with the numerical results of mathematical modelings by the energy method for these three models and the energy dissipation patterns are also compared. And the wave length variations are also included. The experimental results are compared with the numerical results of mathematical modelings by the energy method for these three models and the energy dissipation patterns are also compared. The roll damping moment of the models is increased for zero speed cases, but as the speed increases, the effect of the waves on the roll damping of the models with the additional devices is negligible due to the much increased damping caused by the lift increase.

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단순지지된 비등방성 대칭 적층 원통형 쉘의 해석 (Analysis of Simple Supported Anisotropic Symmetric Laminated Cylindrical Shells)

  • 채상윤;임성순;장석윤
    • 한국강구조학회 논문집
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    • 제11권2호통권39호
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    • pp.117-129
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    • 1999
  • 본 연구의 목적은 복합재료의 이점을 증명하고, 비등방성 대칭 적층 원통형 쉘의 거동을 분석하는 것으로서, 비등방성 대칭 적층 원통형 쉘을 해석하기 위해서 전진차분법, 중앙차분법, 후진차분법으로 구성되어 있는 유한차분법을 적용하였다. 본 연구에서는 처짐과 모멘트를 자유도로 고려하였으며, 이는 모멘트 계산시 발생할 수 있는 오차를 줄일 수 있는 장점을 가지고 있다. 또한 4변이 모두 단순지지된 경계조건을 고려하였다. 수치해석 결과, 유한차분법에 의한 본 연구의 프로그램이 비등방성 대칭 적층 원통형 쉘의 해석에 적합함을 알 수 있으며, 효과적인 보강섬유의 배치 방법을 제시하였다.

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유기플라스틱 결정체의 PMR 연구 (제 1 보). 피발산 (PMR in Organic Plastic Crystals (I). Pivalic Acid)

  • 최종권;잔 그레함
    • 대한화학회지
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    • 제19권3호
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    • pp.149-155
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    • 1975
  • 플라스틱 결정체인 피발산의 temperature-dependent wide-line NMR line width, second monent 및 spin-lattice relaxation times 의 결과는 이 결정체의 특이한 운동학적 성질 및 수소결합에 기인된 것으로 해석된다. 이 분자의 운동학적 성질은 $C_3-C_3'$ reorientation 및 self-diffusion 으로 구성 되었음을 확인했다. Wide-line NMR 연구결과는 또한 Pople-Karasz 융해설과 비교검토되었고, 이 이론과의 차이점은 피발산의 수소결합에 기인되었음을 알아냈다.

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소리의 특성 및 청지각기능에 대한 고찰 (A Study on the Nature of Sound and the Hearing Mechanism)

  • 이정학;김진숙
    • 음성과학
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    • 제5권1호
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    • pp.167-179
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    • 1999
  • The hearing mechanism is a complicated system. Sound is generated by a source that sends out air pressure or power. The pressure or power makes the sound waves. These waves reach the eardrum, or tympanic membrane, which vibrates at a rate and magnitude proportional to the nature of the sound waves. The tympanic membrane transforms this vibration into the mechanical energy in the middle ear, which in turn converts it to the hydraulic energy in the fluid of the inner ear. The hydraulic energy stimulates the sensory cells of the inner ear which send neuroelectrical impulses to the central auditory nervous system. The passive perception of auditory information starts just here. The listener gives attention to the speech sound, differentiates the sound from background noise, and integrates his experience with similar sounds. The listener then puts all of these aspects of audition into the context of the moment to identify the nature of sound. This has a major role in human communication. This paper provides an overview of the nature and characteristics of sound, the structure and function of the auditory system, and the way in which sound is processed by the auditory system.

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