• Title/Summary/Keyword: Geometric Characteristics

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A Knowledge-based System for Analyzing Sophisticated Geometric Structure of Document Images (문서 영상의 정교한 기하적 구조분석을 위한 지식베이스 시스템)

  • Lee, Kyong-Ho;Choy, Yoon-Chul;Cho, Sung-Bae
    • Journal of KIISE:Software and Applications
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    • v.28 no.11
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    • pp.795-813
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    • 2001
  • Sophisticated geometric structure analysis must be preceded to create electronic document from logical components extracted from document image. this paper presents a knowledge-based method for sophisticated geometric structure analysis of technical journal pages. The proposed knowledge base encodes geometric characteristics that are not only common in technical journals but also publication-specific in the form rules. The method takes the hybrid of top-down and bottom-up techniques and consists of two phases: region segmentation and identification. Generally, the result of segmentation process does not have a one-to-one matching with composite layout components. Therefore, the proposed method identifies non-text objects such as image, drawing and table, as well as text objects such as text line and equation by splitting or grouping segmented regions into composite layout components. Experimental results with 372 images scanned from the IEEE Transactions on Pattern Analysis and Machine Intelligence show that the proposed method has performed geometrical structure analysis successfully on more than 99% of the test images, resulting in sophisticated performance compared with previous works.

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Stability and PSR(Power-Supply Rejection) Models for Design Optimization of Capacitor-less LDO Regulators (회로 최적화를 위한 외부 커패시터가 없는 LDO 레귤레이터의 안정도와 PSR 성능 모델)

  • Joo, Soyeon;Kim, Jintae;Kim, SoYoung
    • The Journal of Korean Institute of Electromagnetic Engineering and Science
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    • v.26 no.1
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    • pp.71-80
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    • 2015
  • LDO(Low Drop-Out) regulators have become an essential building block in modern PMIC(Power Managment IC) to extend battery life of electronic devices. In this paper, we optimize capacitor-less LDO regulator via Geometric Programming(GP) designed using Dongbu HiTek $0.5{\mu}m$ BCDMOS process. GP-compatible models for stability and PSR of LDO regulators are derived based on monomial formulation of transistor characteristics. Average errors between simulation and the proposed model are 9.3 % and 13.1 %, for phase margin and PSR, respectively. Based on the proposed models, the capacitor-less LDO optimization can be performed by changing the PSR constraint of the design. The GP-compatible performance models developed in this work enables the design automation of capacitor-less LDO regulator for different design target specification.

Simulation Study for the Distortion Correction of Digital Angiographic Images using Geometric Transformation (디지털 혈관 조영상의 기하학적 왜곡 보정을 위한 모의 실험 연구)

  • 진호상;신동훈;허순녕;곽철은;최보영;이형구;서태석
    • Journal of Biomedical Engineering Research
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    • v.23 no.5
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    • pp.365-373
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    • 2002
  • Accurate localization of target lesion is required to protect normal peripheral tissue and irradiate exactly to tumors in stereotactic radiosurgery(SRS). Digital angiography is one of the most effective diagnostic tools to detect and identify the target tumors. However, it shows pincushion distortion due to the characteristics of the image intensifier. We have implemented a simulation study for the correction of distortion using the geometric transformation. Phantom images were produced transformation. In conclusion, the geometric transformation could effectively be used for the pincushion distortion of image intensifier and there was no significant different between two methods indicating 2% correction error from the ideal image in all cases.

Transparent Plate Thickness Measurement Approach Using a Chromatic Confocal Sensor Based on a Geometric Phase Lens (기하 위상 렌즈 기반의 색공초점 센서를 이용한 투명 물질 두께 측정 연구)

  • Song, Min Kwan;Park, Hyo Mi;Joo, Ki-Nam
    • Korean Journal of Optics and Photonics
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    • v.33 no.6
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    • pp.317-323
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    • 2022
  • In this investigation, we describe a chromatic confocal sensor based on a geometric phase lens for measuring the thicknesses of transparent plates. In order to design a compact sensor, a geometric phase lens, which has diffractive and polarizing characteristics, is used as a device to generate chromatic aberration, and a fiber optic module is adopted. The systematic error of the sensor is reduced with wavelength peak detection by Gaussian curve fitting and the common error compensation obtained by the repeatedly consecutive experimental results. An approach to calculate the plate thickness is derived and verified with sapphire and BK7 plates. Because of the simple and compact design of the proposed sensor with rapid measurement capability, it is expected to be widely used in thickness measurements of transparent plates as an alternative to traditional approaches.

Modern Control of Space and the British Empire's Management of Irish Territory (공간의 근대적 규율과 영국 제국의 아일랜드 영토 경영)

  • Lee, Sungbum
    • Journal of English Language & Literature
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    • v.57 no.4
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    • pp.553-580
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    • 2011
  • This article addresses how the British Empire administered the discipline of space in nineteenth century Ireland. Space control is a part of modern disciplinary practices. I approach this issue in light of the two modern mapping of space: the geometric mapping of space and the Romantic mapping of space. The former, as seen in map-making, is characterized by imposing a standardized, stratified grid on space by eliminating local characteristics of nature. On the other hand, the latter, as shown in picturesque landscaping, aims to balance a close-up observation of nature and a far-sighted view of it, with the result of creating an ironic tension of local diversity and perspectival totality. These modern disciplinary projects of space repeat themselves in the British management of the colonized Irish territory. As the British conquer other lands, they put to good use both geometric and Romantic disciplinary methods of space. Supervising the Ordnance Survey of Ireland from 1824 to 1846, Thomas Frederick Colby, British Director of Ordnance Survey, made a mathematically strict and scientific mapping of Ireland as a scale of six inches to one mile. Parallelled to this geometric colonization of space, the Romantic colonization of space is efficiently used for the Empire's management of Ireland as well. British tourists and pro-unionist Anglo-Irish landed gentries transform it into the nature of picturesque beauty; Ireland's wild boglands turn aesthetically into desolate but beautiful scenery. Picturesque landscape in England is reborn as an aesthetics of desolation in Ireland.

Experimental study on aerodynamic characteristics of launcher at subsonic speed (아음속 유동에서의 발사체의 공력특성에 관한 실험 연구)

  • 노오현;이동호;김원욱;김철완
    • 제어로봇시스템학회:학술대회논문집
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    • 1988.10a
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    • pp.608-613
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    • 1988
  • Subsonic aerodynamic force and moment characteristics have been determined for parametric groups of launchers. Geometric variables considered in the experimental study were body length, nose planform, fin planform (body-alone contained), number of stage and existence of extrnal booster, All data were obtained for angles of attack from 0 to 27 deg in 3-deg. increments.

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Optimal Design and Development of Electromagnetic Linear Actuator for Mass Flow Controller

  • Chung, Myung-Jin;Gweon, Dae-Gab
    • Journal of Mechanical Science and Technology
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    • v.17 no.1
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    • pp.40-47
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    • 2003
  • In this paper, we constructed the analytic model of control valve as a function of electric and geometric parameters, and analyzed the influence of the design parameters on the dynamic characteristics. For improving the dynamic characteristics, optimal design is conducted by applying sequential quadratic programming method to the analytic model. This optimal design aims to minimize the response time and maximize force efficiency. By this procedure, control valve can be designed to have fast response in motion.

Performance Characteristics of Time Delay and Integration(TDI) Satellite Imager for Altitude Change and Line-Of-Sight Tilt over Spherical Earth Surface

  • Cho, Young-Min
    • Proceedings of the KSRS Conference
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    • 2002.10a
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    • pp.216-221
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    • 2002
  • A spherical Earth surface is used fur realistic analysis of the geometrical performance characteristics about the variation of satellite altitude and 2-dimensional line-of-sight(LOS) tilt angle in a satellite imager using Time Delay and Integration(TDI) technique with fixed integration time. In the spherical Earth surface model TDI synchronization using LOS tilt is investigated as a solution to compensate geometric performance degradation due to altitude decrease. This result can be used fur a TDI CCD imager with variable integration time in a certain as well.

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Effect of Screw Geometries on Pull-out Characteristics of Screw Anchor Piles Using Reduced Scale Model Tests (스크류 제원이 스크류 앵커 파일의 인발저항 특성에 미치는 영향에 관한 축소모형실험)

  • Yoo, Chung-Sik
    • Journal of the Korean Geotechnical Society
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    • v.28 no.1
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    • pp.5-15
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    • 2012
  • This paper presents the results of an investigation into the pull-out characteristics of screw anchor piles for use in braced excavation and cut-slope. A series of reduced-scale model tests were performed on model screw anchor piles with different geometric characteristics such as screw size and pitch length. The results indicated that the pullout resistance increases with decreasing the pitch length for a given screw size. It was also observed that the pullout capacity of a screw anchor pile increases with the screw size up to a certain size beyond which the increase becomes minimal. The results are presented in such a way that the pullout characteristics of screw piles with different screw geometric characteristics can be identified. Practical implications of the findings are discussed.

Characteristics of Neo-deconstruction expressed in the Jacquemus fashion collection (자크뮈스 패션 컬렉션에 표현된 신-해체주의 특성)

  • Yoo, Song Joo;Lee, Younhee
    • Journal of the Korea Fashion and Costume Design Association
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    • v.23 no.4
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    • pp.39-56
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    • 2021
  • The purpose of this study was to observe the expressive characteristics of Neo-Deconstruction design, examine the expressive characteristics of Neo-Deconstruction design in the collections of Jacquemus, and analyze their internal meanings. For research, observations were made based on the concepts and expressive characteristics of Deconstruction through prior research and literary review, and analysis was conducted focusing on the expressive characteristics of Neo-Deconstruction. The scope of analysis included a total of 605 photographs collected from a total of 17 season collections of Jacquemus from the 2013 S/S to the 2021 S/S season. The results are as follows. First, the Neo-Deconstruction of Jacquemus expresses the youth culture using bright images such as diverse colors and patterns with 'positive playfulness' and pass on positive messages with deconstructive and playful forms, such as exaggeration and reduction and recombination and reconstitution. Second, with tendencies of 'symbolic receptivity', Jacquemus gained inspiration from his own life, memories, and hometown, and attempted to express the street women of places such as southern France, Paris, and Monaco in a number of collections. Also, he proposed designs that can be worn easily by anyone, regardless of gender, and as plus size models began to become more common respect was given to the tastes and preferences of diverse individuals without distinctions based on body type or sexuality. Third, 'geometric simplicity' was generally expressed by pursuing simple and practical fashion with the addition of details, such as geometric forms including stripes or asymmetrical expressions centering around everyday material that is used in clothing. Fourth, with "open communication," Jacquemus constructed his identity by addressing the various needs of consumers based on social network services and continuously sharing his creative ideas with the public. He is gaining popularity in a unique way by responding quickly to the changing atmosphere of society.