• Title/Summary/Keyword: pre-ghost

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Performance analysis of decision feedback equalizer with dual-feedback in pre-ghost channel (이중 후방필터 구조 결정 궤환 등화기의 선행 고스트에 대한 성능 분석)

  • Oh, Young-Ho;Lee, Kyoung-Won;Kim, Dae-Jin
    • Journal of Broadcast Engineering
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    • v.12 no.5
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    • pp.516-524
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    • 2007
  • In order to use limited frequency resources efficiently, a single frequency network using digital on-channel repeater(DOCR) has been studied and would be implemented. The DOCR generates strong pre-ghosts to ATSC DTV receivers. The forward filter of equalizer in ATSC DTV receivers compensates the distortion made by pre-ghosts. This process induces noise enhancement and colored noise, thereby results in the performance degradation. In this paper we propose to use a dual-feedback equalizer to combat strong pre-ghosts. The proposed equalizer has two feedback filters. One is the decision feedback filter and the other is non-decision feedback filter. The additional non-decision feedback filter decreases the noise by whitening the noise and preventing the generation of colored noise in pre-ghost channel. Thus the equalization technique of dual-feedback structure has performance enhancement in pre-ghost channel in comparison with conventional decision feedback equalizer(DFE). By simulation we analyzed the performance enhancements of DTV receiver using dual-feedback equalization structure.

Adaptive Frame Selection Algorithm for OFDM systems (OFDM 시스템을 위한 적응 프레임 선택 알고리듬)

  • 김정진;류영재;한동석
    • Proceedings of the IEEK Conference
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    • 2001.09a
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    • pp.631-634
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    • 2001
  • OFDM(orthogonal frequency division multiplexing) 시스템은 유효심볼의 뒷부분 일부를 복사하여 유효심볼 이전에 미리 전송하는 보호구간을 이용하여 다중경로에 의한 왜곡을 줄일 수 있다. 그러나, 유효심볼의 시작점을 정확히 판단하더라도 열악한 다중경로 또는 프리-고스트(pre-ghost) 채널의 영향으로 인해 심볼간 간섭(inter-symbol interference)이 발생한다. 본 논문에서는 다중경로 환경하의 기존 시스템에서 발생하던 심볼간 간섭을 제거할 수 있는 프레임 선택 알고리듬을 제안한다. 프레임 선택 알고리듬은 FFT 입력으로 유효심볼의 뒤 알부 대신 보호구간의 일부를 사용한다. FFT 입력으로 사용된 보호구간내 교체구간은 다중경로 환경에 따라 달라져야 하는데, 교체구간 판단을 위한 네 가지 알고리듬도 소개한다. 제안한 알고리듬을 DVB-T(digital video broadcasting-terrestrial) 시스템에 적용한 모의실험을 통하여 3 dB 이상의 성능향상을 얻을 수 있다.

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A NUMERICAL STUDY ON A THIN FILM MANUFACTURING PROCESS USING THE CONTROL OF SURFACE ENERGY OF A MICRODROPLET (미세액적의 표면에너지 제어를 통한 박막 제조 공정에 대한 연구)

  • Suh, Y.;Son, G.
    • 한국전산유체공학회:학술대회논문집
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    • 2008.03a
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    • pp.221-226
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    • 2008
  • Numerical simulation is performed for microdroplet deposition on a pre-patterned micro-structure. The level-set method for tracking the liquid-gas interface is extended to treat the immersed (or irregular-shaped) solid surface. The no-slip condition at the fluid-solid interface as well as the matching conditions at the liquid-gas interface is accurately imposed by incorporating the ghost fluid approach based on a sharp-interface representation. The method is further extended to treat the contact angle condition at an immersed solid surface. The present computation of a patterning process using microdroplet ejection demonstrates that the multiphase characteristics between the liquid-gas-solid phases can be used to improve the patterning accuracy.

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A NUMERICAL STUDY ON A THIN FILM MANUFACTURING PROCESS USING THE CONTROL OF SURFACE ENERGY OF A MICRODROPLET (미세액적의 표면에너지 제어를 통한 박막 제조 공정에 대한 연구)

  • Suh, Y.;Son, G.
    • 한국전산유체공학회:학술대회논문집
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    • 2008.10a
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    • pp.221-226
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    • 2008
  • Numerical simulation is performed for microdroplet deposition on a pre-patterned micro-structure. The level-set method for tracking the liquid-gas interface is extended to treat the immersed (or irregular-shaped) solid surface. The no-slip condition at the fluid-solid interface as well as the matching conditions at the liquid-gas interface is accurately imposed by incorporating the ghost fluid approach based on a sharp-interface representation. The method is further extended to treat the contact angle condition at an immersed solid surface. The present computation of a patterning process using microdroplet ejection demonstrates that the multiphase characteristics between the liquid-gas-solid phases can be used to improve the patterning accuracy.

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Numerical Study on a Thin Film Patterning Process Using Microdroplet Ejection (미세액적의 분사를 이용한 박막 패터닝 공정에 대한 수치적 연구)

  • Suh, Young-Ho;Son, Gi-Hun
    • 한국전산유체공학회:학술대회논문집
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    • 2008.03b
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    • pp.658-659
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    • 2008
  • Numerical simulation is performed for a microdroplet deposition on the pre-patterned micro-structure. The liquid-air interface is tracked by level set method improved by incorporating the ghost fluid approach based on a sharp-interface representation. The method is further extended to treat the contact angle condition at an immersed solid surface. The present computation of a patterning process using microdroplet ejection demonstrates that the multiphase characteristics between the liquid-gas-solid phases can be used to overcome the patterning error.

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Henry James's The Turn of the Screw: The Subject and the Ontological Status of the Real Gaze

  • Kim, Kyung-Soon
    • Journal of English Language & Literature
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    • v.57 no.6
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    • pp.999-1016
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    • 2011
  • In The Turn of the Screw, the go'erness encounters with the apparitions that harrow her throughout the story: she sees a frightening male ghost that Mrs. Grose identifies as Peter Quint, deceased former 'alet of the children's uncle, who had pre'iously shared the charge of the children with the pre'ious go'erness, Miss Jessel. The appearance of the ghosts hails the go'erness and thereby forces her to be jarred out of the comfortable habits of indi'iduality and plunged into a negati'ity de'oid of the socio-normati'e directi'es and guarantees. Such an encounter shows the idea that consciousness is a plenum of existence e'ocati'e of human mind as a decentered pandemonium. For the go'erness in The Turn of the Screw, the foundation to force her to experience the uncanny, as an inconsistency in the symbolic order, is particular. Its particularity is absolute in the same way e'ery one of us dreams his or her world. It resists mediation and cannot be made part of a symbolic medium. Just as Lacan's conceptions of desire, feminine sexuality, 'Object a,' not-whole, sla'ery, mastery, self-deception, authenticity, and act of psychoanalysis help us understand our contradictory social reality, so does The Turn of the Screw help us make sense of the way the go'erness, as the being who is capable of raising the question of being, questions the idea of being. In conclusion, the particular way the go'erness dreams her world is e'ocati'e of an excessi'e being, an anatomical complement, and a particular experience, such as the go'erness's encounter with the ghosts testifies to a knowledge that escapes the knowledge of the speaking being.

A Study on the Regimen thought of Baopuzi inner chapters (『포박자내편(抱朴子內篇)』의 양생사상 연구)

  • Shin, Jin Sik
    • The Journal of Korean Philosophical History
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    • no.43
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    • pp.231-266
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    • 2014
  • The main contents of Baopuzi inner chapters becomes the basis for the claim "to be achieved Xian the way people can be" named and Shenxian theory that is deployed in the center of the universe body theory with a focus on Xuan and YI and Tao and a problem of "demonstration of Shenxian exist", or ancient science that describes the Chinese alchemy and Taoism spell in other words, inner chapters are writing and how to get prescription way of Shenxian, of medicine to become a predecessors, elephant of some of the changes in the ghost apparition, the longevity, how to avoid the epidemic out of the evil. Inner chapters are presented a regimen thought, the rationale for its mystical religion and philosophy of Monasticism ship on the basis of the theory Shenxian so. Baopuzi Inner chapters is presented in detail how to reach a comprehensive and realistic Shenxian long life in prison without the pre-Qin dynasty Taoism and Qinhan dynasty and times across the Weijin dynasty Shenxian ideas. And is presented in a typical Waidan and Neidan Taoism exercise this system and that in Taoism (Regimen) Thought the important position. Thought of Regimen is very important right information Inner chapters which constitutes the establishment of an important theoretical basis Shenxian Taoism of Gehong this research right in that you can see at a glance the thought of Regimen of Inner chapters is the desperate need for this requirement. It aims to illuminate the entire look of Regimen ever appeared immediately in Inner chapters this paper. After the analysis of the body Tao theory, The theory of the body and the spirit, The theory of Xingming, The theory of Shenxian theoretical foundations of thought appeared in Inner chapters Based on this, the first one conducted regulating the qi flowing in the channels method, Daoyin method, Pranayama, Closed breath, I saw one at the specifics of regimen method such, art of controlling and swallowing breath from the mouth, Convinced, Tuna breathing, Sishenshouyi method, Jinehuandan method, Fangzhongshu. And reporting features found Inner chaptersfinally saw the spirit of Regimen weigh its value.