• 제목/요약/키워드: inter-conversion

검색결과 88건 처리시간 0.019초

Inter-Conversion Matrix for Transcoding Block DCT and DWT-Based Compressed Images

  • Kim, Donggyun;Lim, Sanghee;Paik, Joonki
    • IEIE Transactions on Smart Processing and Computing
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    • 제3권3호
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    • pp.103-109
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    • 2014
  • This study derived the inter-conversion matrices, which can be used in heterogeneous image transcoding between the compressed images using different transforms, such as the $8{\times}8$ block discrete cosine transform (BDCT) and the one-level discrete wavelet transform (DWT). Basically, to obtain the one-level DWT coefficients from $8{\times}8$ BDCT, inverse BDCT should be performed followed by forward DWT, and vice versa. On the other hand, if the proposed interconversion approach is used, only one inter-conversion matrix multiplication makes the corresponding transcoding possible. Both theoretical and experimental analyses showed that the amount of computation of the proposed approach decreases over 20% when the inter-conversion matrices are used under specific conditions.

제어법칙 간 상호 전환 시 과도응답 최소화를 위한 전환시간에 관한 연구 (A Study on the Conversion Time to Minimize of Transient Response during Inter-Conversion between Control Laws)

  • 김종섭
    • 항공우주시스템공학회지
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    • 제9권1호
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    • pp.12-18
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    • 2015
  • The inter-conversion between different control laws in flight has a lot of risk. The SWM(Switching Mechanism) including logic and stand-by mode is designed to analyze the transient response of aircraft during inter-conversion between different control laws, based on the in-house software for non-real-time and real-time simulation. The SWM applies the fader logic of TFS(Transient Free Switch) to minimize the transient response of an aircraft during the inter-conversion, and applies the reset '0' type of the stand-by mode to prevent surface saturation due to integrator effect in the disengaged flight control law. The transition time is also important to minimize the objectionable transient response in the inter-conversion, as well as the transition control law design. This paper addresses the results of non-real-time simulation for the characteristics of transient response to different transition time to select the adequate transient time, and the real-time pilot evaluation, using SSWM(Software Switching Mechanism) and HSWM(Hardware Switching Mechanism), which is met for Level 1 flying qualities and assures safety of flight.

Inter-conversion between the power and Arnoldi`s methods

  • Park, Pil-Seong
    • 대한수학회논문집
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    • 제12권1호
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    • pp.145-155
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    • 1997
  • We present a couple of tools that can be used in the solution of nonsymmetric eigenvalue problems. The first one allows us to convert power iterates into Arnoldi's results so that a few eigenpairs are easily obtainable. The other converts Arnoldi's results into power iterates to simulate the power method and improve the result. Suggestions for application are also given.

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Polymer/fullerene/LiF inter-layer BHJ 유기태양전지의 광학 및 전기적 특성에 대한 연구 (Electrical and optical characterizations of OSCs based on polymer/fullerene BHJ structures with LiF inter-layer)

  • 송윤석;김승주;류상욱
    • 반도체디스플레이기술학회지
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    • 제10권1호
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    • pp.27-32
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    • 2011
  • In this study, we have investigated the power conversion efficiency of organic solar cells utilizing conjugated polymer/fullerene bulk-hetero junction(BHJ) device structures. We have fabricated poly(3-hexylthiophene)(P3HT), poly[2methoxy-5-(3',7'-dimethyloctyl-oxy)-1-4-phenylenevinylene] as an electron donor, [6,6]-phenyl $C_{61}$ butyric acid methylester(PCBM-$C_{61}$)as an electron acceptor, and poly(3,4-ethylenedioxythiophene)-poly(styrenesulfonate)(PEDOT:PSS) used as a hole injection layer(HIL), after fabricated active layer, between active layer and metal cathode(Al) deposited LiF interlayer(5 nm). The properties of fabricated organic solar cell(OSC) devices have been analyzed as a function of different thickness. The electrical characteristics of the fabricated devices were investigated by means J-V, fill factor(FF) and power conversion efficiency(PCE). We observed the highest PCEs of 0.628%(MDMO-PPV:PCBM-$C_{61}$) and 2.3%(P3HT:PCBM-$C_{61}$) with LiF inter-layer at the highest thick active layer, which is 1.3times better than the device without LiF inter-layer.

"황제내경(黃帝內經)"의 청(精), 신(神)과 음양변화(陰陽變化)에 대한 고찰(考察) (A Study on The Jeong(精), Sin(神) and Eumyang Changes(陰陽變化) in "Hwangjenaegyeong(黃帝內經)")

  • 백유상;윤은경
    • 대한한의학원전학회지
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    • 제24권1호
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    • pp.47-55
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    • 2011
  • Jeong(精) and Sin(神) have very close relation in "Hwangjenaegyeong(黃帝內經)", and jeong(精) is base of sin(神). Jeong is the origin of life force, Sin can be manifested through the Yin-yang inter conversion of Jeong, on the other hand, Jeong can be created through the same conversion of Sin. The Yin-yang inter conversion of Jeong or Sin, means the inclination of Taegeuk(太極) to Unification after division, in this process, life force and creative power are made.

Biotransformation of withanolides by cell suspension cultures of Withania somnifera (Dunal)

  • Sabir, Farzana;Sangwan, Rajender S.;Singh, Jyoti;Misra, Laxmi N.;Pathak, Neelam;Sangwan, Neelam S.
    • Plant Biotechnology Reports
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    • 제5권2호
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    • pp.127-134
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    • 2011
  • The biotransformation potential of cell suspension cultures generated from Withania somnifera leaf was investigated, using withanolides, i.e. withanolide A, withaferin A, and withanone as precursor substrates. Interestingly, the cell suspension cultures showed inter-conversion of withanolides, as well converted to some unknown compounds, released to the culture media. The bio-catalyzed withanolide was detected and quantified by TLC and HPLC, respectively. There is noticeable conversion of withanolide A to withanone, and vice versa though at a lower level. The type of reaction of this biotransformation appears to be substitution of 20-OH group to 17-OH in withanolide A. In this paper, we present for the first time the possibility of biotransformation by inter-conversion of withanolides of pharmacological importance through cell suspension culture of W. somnifera. The possible role of putative cytochrome $P_{450}$ hydroxylases is implicated in the conversion.

SMS 메시지를 RCS-e 메시지로 변환하기 위한 프레임워크에 관한 연구 (A Study on Message Inter-working Framework for sending SMS to RCS-e)

  • 이동철
    • 한국멀티미디어학회논문지
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    • 제17권5호
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    • pp.582-589
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    • 2014
  • Mobile phone users have been using the SMS to send and receive text messages between them. Recently, GSMA(GSM Association) proposed the next generation instant messaging service, RCS-e(Rich Communication Service-enhanced). This was unavoidable because new OTT(Over The Top) services have emerged that threat the SMS after smart phones became popular. However, the RCS-e has limitations that it cannot inter-operate with the SMS which is still widely used. This paper propose a software framework that inter-work SMS with RCS-e. Call flows for canceling wireless contracts and sending SMS messages to RCS-e users were defined. Also, methods for protocol conversion were defined to inter-work two services. The performance evaluation showed that the proposed framework does not increase loads on IMS(IP Multimedia Subsystem) infrastructure.

ICI를 Data Conversion 방식으로 상쇄하는 OFDM 통신시스템과 성능분석 (Performance Analysis of OFDM Communication System Cancelling the ICI by Data Conversion Method)

  • 허근재;이영선;유흥균;정두영
    • 한국전자파학회논문지
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    • 제14권11호
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    • pp.1191-1197
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    • 2003
  • 무선 통신 시스템에서 고속 데이터 전송에 효율적인 다중 반송파 시스템인 OFDM통신 시스템에서는 송수신단의 오실레이터에서 발생하는 위상잡음이 인접채널간 간섭(Inter-carrier-interference: ICI)을 야기시켜 통신 성능에 악영향을 끼친다. 본 논문에서는 ICI영향을 효과적으로 줄일 수 있는 새로운 data-conversion 형식의 ICI 제거 방법을 제안하고 위상잡음을 선형 근사화하여 위상잡음에 의해 발생하는 common phase error(CPE), ICI 그리고 carrier to interference power ratio(CIR)를 분석한다. 그리고 data-conversion 형식의 위상잡음에 의한 성능 개선 효과를 분석하기 위해서 기존의 OFDM과 비교하였다. 이때 부반송파수 64의 조건하에서 위상 잡음 분산 0.3의 QPSK변조방식과 위상 잡음 분산 0.1의 16 QAM변조방식의 경우, BER=$10^{-3}$에서 각각 0.6 ㏈, 1.5 ㏈의 SNR 이득을 가짐을 볼 수 있다. 결과적으로 ICI 제거방법을 사용하였을 때 기존의 OFDM system에 비하여 ICI에 의한 성능손실을 효과적으로 줄일 수 있다.

커패시턴스 오차가 아날로그 디지털 변환의 정확도에 미치는 영향 (Effect of Capacitance Error on the A/D conversion Accuracy)

  • 이윤태;김충기;경종민
    • 대한전자공학회논문지
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    • 제22권5호
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    • pp.57-61
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    • 1985
  • The e(lect of capacitance error on the A/D conversion accuracy in the A/D converter using binary-weighted capacitor array was scruntized. Besides the Monte-Carlo method considering the inter-capacitance ratios as random variables, " correlation approach" con-sidering the correlation coefficient between capacitances is proposed in this paper. Bt was observed by the measurement of capacitances of monolithic MO5 capacitors that the correla-tion coefficient between capacitors decreases as the capacitor size incrrases. It was also verified that the parallel connection of unit capacitors and the common centroid layout scheme signi(icantly increase the inter-capacitance correlation coefficients.

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DC-Offset 간섭환경에서 AC-Coupling을 갖는 직접변환 수신기의 성능 (Performance of Direct-Conversion Receiver with AC-Coupling in DC-Offset interference environment)

  • 성봉훈;송윤정;김영완;김내수;서종수
    • 한국방송∙미디어공학회:학술대회논문집
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    • 한국방송공학회 2002년도 정기총회 및 학술대회
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    • pp.9-14
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    • 2002
  • Direct-conversion receiver(DCR) architecture has superior advantages in size, cost, and power over superheterodyne receiver architectures. However, the use of direct-conversion receiver architecture has been limited due to the direct-current offset noise. The ac coupling, which is used to overcome the direct-current offset noise, causes an inter-symbol interference(ISI), whose effects can be effectively mitigated using an equalizer. In this paper, the performance of a direct-conversion receiver with ac coupling in the presence of direct-current offset is analyzed via computer simulation. The simulation result shows that by using decision feedback equalizer with LMS(Least Mean Square) algorithm, signal-to-noise ratio loss of the direct-conversion receiver compared to the idea receiver can be reduced to less than 1㏈ for corner frequencies as large as 10% of the symbol rate.

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