• Title/Summary/Keyword: time-of-flight(TOF)

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A Study on MPEG-4 Based 3D Video Contents Creation Method using Time-of-Flight Sensor (Time-of-Flight 센서를 이용한 MPEG-4 기반의 3 차원 비디오 콘텐츠 생성기법에 관한 연구)

  • Cho, Ji-Ho;Kim, Sung-Yeol;Yoo, Jae Doug;Lee, Kwan H.
    • Proceedings of the Korea Information Processing Society Conference
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    • 2010.04a
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    • pp.542-545
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    • 2010
  • 본 논문에서는 TOF 카메라를 이용한 3 차원 비디오의 생성하는 방법을 제안한다. 또한 생성된 콘텐츠를 전송 및 재생하기 위해 MPEG-4 멀티미디어 프레임워크를 사용하였다. TOF 센서로 획득한 데이터를 알파매팅 및 깊이 최적화 과정을 거쳐 고품질의 깊이 비디오를 생성하고 MPEG-4 시스템으로 부호화 한 후 전송하여 사용자에게 3 차원 비디오를 제공한다.

Synthesis and Charge Transport of Novel Diphenoquinones(II) (Diphenoquinone 유도체의 합성과 전하이송 (II))

  • Kim, Dae-Young;Jeong, Jae-Hoon;Yu, Kyoung-Hwan;Kim, Beom-Jun;Chung, Su-Tae;Son, Se-Mo
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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    • 2002.07b
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    • pp.994-997
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    • 2002
  • We have synthesized novel Diphenoquinone(DQ) derivatives. Electron drift mobility of DQ series was measured and electron affinity$(E_a)$ of them is estimated 3.7~3.9eV by CV. Electron drift mobility$(\mu)$ of electric field dependence by time of flight(TOF) technique is $1.76{\times}10^{-5}cm^2/V{\cdot}s$(DQ5) at the concentration of 10wt% verse poly(4,4'-cyclohexylidene diphenylcarbonate)(Pc-Z) and $1.66{\times}10^6V/cm$.

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Drift Velocities for Electrons in $SF_6$-Ar Mixtures Gas by MCS-Beq Algorithm (MCS-BEq에 의한 $SF_6-Ar$혼합기체(混合氣體)의 전자(電子) 이동속도(移動速度))

  • Kim, Sang-Nam
    • The Transactions of the Korean Institute of Electrical Engineers P
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    • v.54 no.1
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    • pp.29-33
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    • 2005
  • Energy distribution function for electrons in $SF_6$-Ar mixtures gas by MCS-BEq algorithm has been analysed over the E/N range $30{\sim}300$[Td] by a two term Boltana equation and by a Monte Carlo Simulation using a set of electron cross sections determined by other, authors, experimentally the electron swarm parameters for 0.2[%} and 0.5[%] $SF_6$-Ar mixtures were measured by time-of-flight(TOF) method. The result show that the deduced electron drift velocities, the electron ionization or attachment coefficients, longitudinal and transverse diffusion coefficients and mean energy agree reasonably well with theoretical for a rang of E/N values. The results obtained from Booltemann equation method and Monte Carlo simulation have been compared with present and previously obtained data and respective set of electron collision cross sections of the molecules.

Analysis of electron transport properties of $CF_4+Ar$ mixtures gas by the TOF method (TOF법에 의한 $CF_4+Ar$ 혼합기체의 전자수송특성 해석)

  • 서상현;하성철;유회영
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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    • 1998.06a
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    • pp.279-283
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    • 1998
  • The electron swarm parameters in the$CF_4$(O.l%, 5%)+Ar mixtures are measured by time of flight method over the E/N(Td) range from 10 to 300LTdl. A two-term approximation of the Boltzmann equation analysis and Monte Carlo simulation have been also used to study electron transport coefficients. We have calculated W, NDL, NDT, $\alpha$ and the limiting breakdown electric field to gas mixtures ratio in pure $CF_4$ gas and$CF_4+Ar$ mixtures. The measured results and the calculated results have been compared each other paper.

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Analysis of Folate by Matrix-Assisted Laser Desorption/Ionization Time-of-Flight Mass Spectrometry

  • Cha, Sang-Won;Kim, Hie-Joon
    • Bulletin of the Korean Chemical Society
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    • v.24 no.9
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    • pp.1308-1312
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    • 2003
  • Matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS) was used to observe folic acid and its derivatives such as tetrahydrofolate and 5-methyltetrahydrofolate in a vitamin tablet and in foods. Folic acid in a vitamin tablet was determined using angiotensin I as an internal reference. Tetrahydrofolic acid, 5-methyltetrahydrofolic acid, and an oxygenated folate were observed from a human blood sample using graphite plate. The results show that these mass spectrometric methods are useful for quickly obtaining a profile of folates.

Optimization of Reflectron for Kinetic and Mechanistic Studies with Multiplexed Multiple Tandem (MSn) Time-of-flight Mass Spectrometry

  • Bae, Yong-Jin;Yoon, So-Hee;Moon, Jeong-Hee;Kim, Myung-Soo
    • Bulletin of the Korean Chemical Society
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    • v.31 no.1
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    • pp.92-99
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    • 2010
  • Photoexcitation of a precursor ion inside a cell floated at high voltage installed in a tandem time-of-flight (TOF) mass spectrometer provides triple tandem mass spectrometric information and allows kinetic and mechanistic studies. In this work, the factors affecting, or downgrading, the performance of the technique were identified. Ion-optical and computational analyses showed that an optimum instrument could be designed by utilizing a reflectron with linear-plus-quadratic potential inside. Theoretical predictions were confirmed by tests with instruments built with different ion-optical layout. With optimized instruments, masses of intermediate ions in the consecutive dissociation of a precursor ion could be determined with the maximum error of $\pm5$ Da. We also observed excellent agreement in dynamical parameters (critical energy and entropy) for the dissociation of a model peptide ion determined by instruments with different ion-optical layout operated under optimum conditions. This suggests that these parameters can be determined reliably by the kinetic method developed previously when properly designed and operated tandem TOF instruments are used.

Magnetic Resonance Angiography using 3D Time-Of-Flight Method (Time of Flight 원리를 이용한 삼차원 자기공명 혈관조영술의 구현)

  • Yi, Y.;Ryu, T.H.;Kim, S.S.;Ahn, S.H.;Lee, M.W.;Jung, K.J.
    • Proceedings of the KOSOMBE Conference
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    • v.1998 no.11
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    • pp.96-97
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    • 1998
  • 3D TOF MR Angiography is able to obtain thinner slice thickness, higher SNR, therefore higher spatial resolution than 2D TOF MR Angiography. Since it uses longer TR than 2D TOF MRA to allow stronger in-flow effect, the background tissue may not be fully saturated. Thus background tissue signal can be further suppressed by MTS(Magnetization Transfer Saturation). Flow-compensation was accomplished by GMN(Gradient Moment Nulling), and tracking saturation was used to suppress vein signal. The different flow signal at the entry of the slab and output of the slab can be compensated by TONE(Tilted Optimized Non-saturating Excitation) RF pulse.

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Development of 3D Projection Reconstruction MR Angiography

  • 김대흥;김은주;정은기
    • Proceedings of the KSMRM Conference
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    • 2001.11a
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    • pp.148-148
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    • 2001
  • 목적: 자기 공명 혈관 영상(MR Angiography)법으로 혈관 촬영시, 혈관 협착으로 인하여 난류 현상이 발생되는 곳에서는 영상 자체가 얻어지지 않는다. 기존에 TE를 줄이거나 또는 projection reconstruction 방법은 2차원 TOF(Time of Flight)에 적용이 되어서 좋은 결과를 얻었다. 그런데, 2차원 TOF보다는 3차원 TOF으로 보다 좋은 혈관 영상을 얻을 수가 있다. 하지만, 3차원 TOF 방법에 projection reconstruction 방법을 적용하는 데는 여러 가지 문제점이 있어서 개발되어 있는 것이 거의 없다. 본 연구에서는 3차원 TOF 방법에 projection reconstruction 방법을 적용하여서 혈관내의 난류 현상에 의한 영상의 왜곡을 극복하는 방법을 개발한다. 대상 및 방법: 3차원 projection reconstruction을 위한 pulse sequence를 실제 진단에 사용하는 GE사의 자기공명영상장치(1.5T)에 맞게 독자적으로 개발한다. GE사의 장비에서 자료를 얻어서 일반 컴퓨터에서 영상을 재구성하는 알고리즘을 자체 개발한다. 혈관에서와 비슷한 형태의 난류를 발생시킬 수 있는 기구를 만들어서 실제 혈관영상에 사용하는 방법과 개발한 방법으로 영상을 비교한다.

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3D Fingertip Estimation based on the TOF Camera for Virtual Touch Screen System (가상 터치스크린 시스템을 위한 TOF 카메라 기반 3차원 손 끝 추정)

  • Kim, Min-Wook;Ahn, Yang-Keun;Jung, Kwang-Mo;Lee, Chil-Woo
    • The KIPS Transactions:PartB
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    • v.17B no.4
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    • pp.287-294
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    • 2010
  • TOF technique is one of the skills that can obtain the object's 3D depth information. But depth image has low resolution and fingertip occupy very small region, so, it is difficult to find the precise fingertip's 3D information by only using depth image from TOF camera. In this paper, we estimate fingertip's 3D location using Arm Model and reliable hand's 3D location information that is modified by hexahedron as hand model. Using proposed method we can obtain more precise fingertip's 3D information than using only depth image.

Comparative Proteomic Analyses of the Yeast Saccharomyces cerevisiae KNU5377 Strain Against Menadione-Induced Oxidative Stress

  • Kim, Il-Sup;Yun, Hae-Sun;Jin, In-Gnyol
    • Journal of Microbiology and Biotechnology
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    • v.17 no.2
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    • pp.207-217
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    • 2007
  • The Saccharomyces0 cerevisiae KNU5377 strain, which was isolated from spoilage in nature, has the ability to convert biomass to alcohol at high temperatures and it can resist against various stresses [18, 19]. In order to understand the defense mechanisms of the KNU5377 strain under menadione (MD) as oxidative stress, we used several techniques for study: peptide mass fingerprinting (PMF) by matrix-assisted laser desorption/ionization-time of flight (MALDI-TOF) mass spectrometry (MS) followed by two-dimensional (2D) gel electrophoresis, liquid chromatography electrospray ionization tandem mass spectrometry (LC-ESI-MS/MS), and surface-enhanced laser desorption ionization-time of flight (SELDI-TOF) technology. Among the 35 proteins identified by MALDI-TOF MS, 19 proteins including Sod1p, Sod2p, Tsa1p, and Ahp1p were induced under stress condition, while 16 proteins were augmented under normal condition. In particular, five proteins, Sod1p, Sod2p, Ahp1p, Rib3p, Yaf9p, and Mnt1p, were induced in only stressed cells. By LC-ESI-MS/MS analysis, 37 proteins were identified in normal cells and 49 proteins were confirmed in the stressed cells. Among the identified proteins, 32 proteins were found in both cells. Five proteins including Yel047cp and Met6p were only upregulated in the normal cells, whereas 17 proteins including Abp1P and Sam1p were elevated in the stressed cells. It was interesting that highly hypothetical proteins such as Ynl281wp, Ygr279cp, Ypl273wp, Ykl133cp, and Ykr074wp were only expressed in the stressed cells. SELDI-TOF analysis using the SAX2 and WCX2 chips showed that highly multiple-specific protein patterns were reproducibly detected in ranges from 2.9 to 27.0 kDa both under normal and stress conditions. Therefore, induction of antioxidant proteins, hypothetical proteins, and low molecular weight proteins were revealed by different proteomic techniques. These results suggest that comparative analyses using proteomics might contribute to elucidate the defense mechanisms of KNU5377 under MD stress.