• 제목/요약/키워드: Projection Principle

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데이터분석을 통한 확대투사원리의 효율성 제고 (A Reconsideration on the Efficiency of the Extended Projection Principle)

  • 주치운
    • 한국컴퓨터정보학회논문지
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    • 제16권10호
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    • pp.219-228
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    • 2011
  • 본 연구는 다양한 언어 데이터 분석을 통해 최소주의에서의 확대투사원리에 대한 대안을 제시하는데 역점을 둔다. 확대투사원리는 두 가지 원리에서 도출되는데, 하나는 표준이론에서의 투사원리이고 다른 하나는 주어위치는 반드시 채워야 한다는 요건을 근거한다. 이 두 원리가 하나로 병합된 확대투사원리는 이후에 계속해서 그 개념이 변한다. 최소주의 출현 이전에는 격에 의존적이었으나, Chomsky(1995)의 최소주의 하에서는 범주자질 [D]의 특성으로 귀착된다. 그러나 본 연구에서는 위치 도치 구문, 허사 there 구문, 결속이론과 같은 구문에서의 다양한 언어 데이터를 분석하여 굴절어구의 지정어 위치는 최대로 투사된 어휘항목에 의해 반드시 채워져야 한다는 대안을 제시한다.

Sparse-View CT Image Recovery Using Two-Step Iterative Shrinkage-Thresholding Algorithm

  • Chae, Byung Gyu;Lee, Sooyeul
    • ETRI Journal
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    • 제37권6호
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    • pp.1251-1258
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    • 2015
  • We investigate an image recovery method for sparse-view computed tomography (CT) using an iterative shrinkage algorithm based on a second-order approach. The two-step iterative shrinkage-thresholding (TwIST) algorithm including a total variation regularization technique is elucidated to be more robust than other first-order methods; it enables a perfect restoration of an original image even if given only a few projection views of a parallel-beam geometry. We find that the incoherency of a projection system matrix in CT geometry sufficiently satisfies the exact reconstruction principle even when the matrix itself has a large condition number. Image reconstruction from fan-beam CT can be well carried out, but the retrieval performance is very low when compared to a parallel-beam geometry. This is considered to be due to the matrix complexity of the projection geometry. We also evaluate the image retrieval performance of the TwIST algorithm -sing measured projection data.

변위확대기구를 이용한 선형 초음파 전동기의 효율 개선 (Efficiency Improvement of Linear Ultrasonic Motor Using Arrangement for Magnification of Displacement)

  • 이명훈;우상호;김진수
    • 한국전기전자재료학회:학술대회논문집
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    • 한국전기전자재료학회 2000년도 추계학술대회 논문집
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    • pp.177-180
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    • 2000
  • In this paper, we studied efficiency improvement of linear ultrasonic motor using projection. The principle of ultrasonic motor is to use an elliptic motion generated at the side of the vibrator, and the elliptic motion of the ultrasonic motor was obtained by complex oscillation of L$_1$-B$_4$ mode. As the experimental results, the efficiency of linear ultrasonic motor without projection was 1.52[%] when applied voltage was 56[V] in resonance frequency 58.4[kHz]. The efficiency of linear ultrasonic motor using projection was 3.36[%] when applied voltage was 56[V] in resonance frequency 58.4[kHz]. The efficiency was improved by projection.

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Government and Derivation in Korean Phonology

  • Park, Hee-Heon;David Michaels
    • 대한음성학회:학술대회논문집
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    • 대한음성학회 1996년도 10월 학술대회지
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    • pp.117-122
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    • 1996
  • This paper proposes a derivational account of tensing and neutralization of obstruents in Korean within the theory of Government Phonology (GP) (Kaye, Lowenstamm and Vergnaud 1990, henceforth KLV; Park 1996). We begin by outling the relevant tensing and neutralization data in Korean. We point out several problems that need to be addressed in any account of these data. We then set out the central notions of GP, pointing out how adherence to the requirement that government relations remain constant throughout a derivation under the Projection Principle prevents a GP account of tensing and neutralization in Korean, which requires government relations to switch between lexical and phonetic representations. To address this problem, we propose abandoning the Projection Principle, extending lexical representations in GP along the lines of the Markedness Theory approach (Michaels 1989), and adopting the economy principles for derivation of the Minimalist approach (Chomsky 1993; Chomsky & Lasnik 1991). finally, we summarize the analysis of obstruent phenomena in Korean within GP extended in these ways.

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영어 형태론에서의 음운 제약 (Phonological Constraints in English Morphology)

  • 김영석
    • 한국영어학회지:영어학
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    • 제3권4호
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    • pp.547-570
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    • 2003
  • There are a fair number of suffixes in English whose conditions on attachment refer to stress and/or segmental information contained within the words they attach to (see Siegel 1974, Jespersen 1942 and Marchand 1969). Through a wide study of relevant data, we will delve deeply into such phonological restrictions on the bases, which may as well be divided into four distinct types: haplological constraints; segmental constraints; prosodic constraints; and mixed types. We will further assume here that the category/ subcategorization requirements of affixes are subject to the Projection Principle (PP) as conceived in Kiparsky (1983). It will be shown how this PP interacts with phonological constraints placed upon the affix in question, especially in the treatment of-ful (inventful/mournful) or -en (longen/lengthen). Our account of problematic affixations in English is based on a number of violable constraints in OT.

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3D Projection Screen using Advanced Volume Holography

  • Okamoto, Masaaki;Shimizu, Eiji
    • 한국정보디스플레이학회:학술대회논문집
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    • 한국정보디스플레이학회 2002년도 International Meeting on Information Display
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    • pp.1005-1008
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    • 2002
  • The authors introduce 3D display systems developed in our laboratories for recent ten years. Those are mainly realized by several technologies in holography: electro-holography. holographic stereogram, holographic optical elements (HOE) and hologram screen. We are currently focusing the development of 3D projection screen without glasses. Powerful directionality of the light beam is required for 3D projection screen unlike 2D type. We succeeded in achieving the superior diffractive efficiency of hologram screen that is based on the advanced volume holography. This technology is extensively useful to retrieve the Bragg condition of volume hologram in the three-dimensional space. Owing to this technology we could establish the principle of multi-view projection screen and have confirmed the case of 4 viewing points.

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93 대전엑스포 꿈돌이 조각가로보트의 인물형상 측정시스템 (3-D Profile Measurement System of Live Human Faces for the '93 Taejon Expo Kumdori Robot Scupltor)

  • 김승우;박현구;김문상
    • 대한기계학회논문집
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    • 제19권3호
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    • pp.670-679
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    • 1995
  • This paper presents the 3-D profile measurement system of live human faces, which was developed specially for 'KUMDORI sculptor robot' of the '93 Taejon Exposition. '93 Taejon EXPO. The basic principle for measurement adopts the slit beam projection which is a method of measuring 3-D surface profiles using geometric optics between the slit beam and the CCD camera. Since the slit beam projection consumes long measuring time, it is unfit to measure the 3-D profiles of living objects as human. Therefore, the projection type slit beam method which consumes short measuring time is newly suggested. And an algorithm to reconstruct the 3-D profile from the deformed images using finite approximated calibration is suggested and practically implemented. The projection type slit beam method was applied to spectators in a period of '93 Taejon EXPO. The measurement results show that the technique is suitable for 3-D face profile measurement on a living body.

Orthogonalization principle for hybrid control of robot arms under geometric constraint

  • Arimoto, Suguru
    • 제어로봇시스템학회:학술대회논문집
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    • 제어로봇시스템학회 1992년도 한국자동제어학술회의논문집(국제학술편); KOEX, Seoul; 19-21 Oct. 1992
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    • pp.1-6
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    • 1992
  • A principle of "orthogonalization" is proposed as an extended notion of hybrid (force and position) control for robot manipulators under geometric endpoint constraints. The principle realizes the hybrid control in a strict sense by letting position and velocity feedback signals be orthogonal in joint space to the contact force vector whose components are exerted at corresponding joints. This orthogonalization is executed via a projection matrix computed in real-time from a gradient of the equation of the surface in joint coordinates and hence both projected position and velocity feedback signals become perpendicular to the force vector that is normal to the surface at the contact point in joint space. To show the important role of the principle in control of robot manipulators, three basic problems are analyzed, the first is a hybrid trajectory tracking problem by means of a "modified hybrid computed torque method", the second is a model-based adaptive control problem for robot manipulators under geometric endpoint constraints, and the third is an iterative learning control problem. It is shown that the passivity of residual error dynamics of robots follows from the orthogonalization principle and it plays a crucial role in convergence properties of both positional and force error signals.force error signals.

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Metal Area Segmentation in X-ray CT Images Using the RNA (Relevant Neighbor Ar ea) Principle

  • Kim, Youngshin;Kwon, Hyukjoon;Kim, Joongkyu;Yi, Juneho
    • 한국멀티미디어학회논문지
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    • 제15권12호
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    • pp.1442-1448
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    • 2012
  • The problem of Metal Area Segmentation (MAS) in X-ray CT images is a very hard task because of metal artifacts. This research features a practical yet effective method for MAS in X-ray CT images that exploits both projection image and reconstructed image spaces. We employ the Relevant Neighbor Area (RNA) idea [1] originally developed for projection image inpainting in order to create a novel feature in the projection image space that distinctively represents metal and near-metal pixels with opposite signs. In the reconstructed result of the feature image, application of a simple thresholding technique provides accurate segmentation of metal areas due to nice separation of near-metal areas from metal areas in its histogram.

무대조명용 LED 광학시스템 설계 및 시뮬레이션 결과 (The Optical Design and Simulation Results for LED Stage Lighting System)

  • 박광우;주재영
    • 조명전기설비학회논문지
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    • 제29권4호
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    • pp.30-36
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    • 2015
  • The principle of an illumination and projection system including LED light sources for a spot type stage lighting system was presented, and its optical system was designed with optimizing parameters by the analytical methods. A dichroic mirror incorporated with an illumination system to optimizing LED source positions and to obtain the compact system. The projection system was optimized with specific constraints such as a chromatic aberration, distortion aberration and angle of incidence angles. Optimized design system has a beam angle from $10^{\circ}$ to $45^{\circ}$, and its illuminance was 4,500lux at distance of 6m on the work plane.