• Title/Summary/Keyword: LDS

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Analysis of a wavelength tunable source according to temperature variations in a Mutually Injected F-P LD (상호주입 잠김 F-P LD에서 온도변화에 따른 가변 파장 광원의 특성 분석)

  • Hwang, Ji-hong;Oh, Yeong-guk;Lee, Hyuek-jae;Lee, Chang-hee
    • Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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    • 2012.10a
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    • pp.1009-1011
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    • 2012
  • In this paper, a wavelength tunable light source based on mutually injected locking with two F-P LDs, has been constructed and then analyzed for wavelength shift and RIN (Relative Intensity noise) according to temperature. We have measured maximum about 2 nm for the wavelength shift and minimum -110dB/hz for the RIN. Also, the RIN and beating noise in eye patterns are increased by changing temperature high.

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Serum Enzyme Values after Extracorporeal Circulation (체외순환후의 혈청효소치 변동에 관한 연구)

  • Lee, Sang-Ho;Kim, Chong-Whan
    • Journal of Chest Surgery
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    • v.14 no.2
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    • pp.144-152
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    • 1981
  • The effect of cardiopulmonary bypass procedures on the blood components were studied through the measurements of several serum enzymes, SGOT, SGPT, CPK and LDH with its isozymes in the patients who had surgery for their heart diseases. They wre 85 patients: 40 Males and 45 Females. Their ages ranged widely between one and fifty-six. They were divided into 5 groups: Group I.patent ductus arteriosus without extracorporeal circulation, Group II-atrial septal defect, Group III-ventricular septal defect, Group IV-tetralogy of Fallot, and Group V-valve replacement. Generally serum enzymes revealed the increased values after surgery and the tendency returning toward preoperative levels. With the high total serum LDH levels seen uniformly after operation which persisted long in patients with replaced valves, the changes of LDH-isozymes were further analyzed. The isozymes, especially LDI and LDs increased their activities postoperatively, and the other fractions varied little. And $LD_1$/$LD_2$ ratios also showed similar rises and falls while the elevated values lasted longer in the patients with cardiac valve replacement. The significant values of LDH-isozymes in predicting the hemolysis occuring after extracorporeal circulation and in following the patients whose valves were replaced have been further discussed with the special stress placed on the $LD_1$/$LD_2$ratios.

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Development of a Model Based Predictive Controller for Lane Keeping Assistance System (모델기반 예측 제어기를 이용한 차선유지 보조 시스템 개발)

  • Hwang, Jun-Yeon;Huh, Kun-Soo;Na, Hyuk-Min;Jung, Ho-Gi;Kang, Hyung-Jin;Yoon, Pal-Joo
    • Transactions of the Korean Society of Automotive Engineers
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    • v.17 no.3
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    • pp.54-61
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    • 2009
  • Lane keeping assistant system (LKAS) could save thousands of lives each year by maintaining lane position and is regarded as a promising active safety system. The LKAS is expected to reduce the driver workload and to assist the driver during driving. This paper proposes a model based predictive controller for the LKAS which requires cooperative driving between the driver and the assistance system. A Hardware-In-the-Loop-Simulator (HILS) is constructed for its evaluation and includes Carsim, Matlab Simulink and a lane detection algorithm. The single camera is mounted with the HILS to acquire the monitor images and to detect the lane markers. The simulation is conducted to validate the LKAS control performance in various road scenario.

Development of a Lane Keeping Assist System using Vision Sensor and DRPG Algorithm (비젼센서와 DRPG알고리즘을 이용한 차선 유지 보조 시스템 개발)

  • Hwang, Jun-Yeon;Huh, Kun-Soo;Na, Hyuk-Min;Jung, Ho-Gi;Kang, Hyung-Jin;Yoon, Pal-Joo
    • Transactions of the Korean Society of Automotive Engineers
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    • v.17 no.1
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    • pp.50-57
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    • 2009
  • Lane Keeping Assistant Systems (LKAS) require the cooperative operation between drivers and active steering angle/torque controllers. An LKAS is proposed in this study such that the desired reference path generation (DRPG) system generates the desired path to minimize the trajectory overshoot. Based on the reference path from the DRPG system, an optimal controller is designed to minimize the cost function. A HIL (Hardware In the Loop) simulator is constructed to evaluate the proposed LKAS system. The single camera is mounted on the simulator and acquires the monitor images to detect lane markers. The performance of the proposed system is evaluated by HIL system using the Carsim and the Matlab Simulink.

Fabrication of Nd-Substituted Bi4Ti3O12 Thin Films by Metal Organic Chemical Vapor Deposition and Their Ferroelectrical Characterization

  • Kim, Hyoeng-Ki;Kang, Dong-Kyun;Kim, Byong-Ho
    • Journal of the Korean Ceramic Society
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    • v.42 no.4
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    • pp.219-223
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    • 2005
  • A promising capacitor, which has conformable step coverage and good uniformity of thickness and composition, is needed to manufacture high-density non-volatile FeRAM capacitors with a stacked cell structure. In this study, ferroelectric $Bi_{3.61}Nd_{0.39}Ti_3O_{12}$ (BNdT) thin films were prepared on $Pt(111)/TiO_2/SiO_2/Si$ substrates by the liquid delivery system MOCVD method. In these experiments, $Bi(ph)_{3}$, $Nd(TMHD)\_{3}$ and $Ti(O^iPr)_{2}(TMHD)_{2}$ were used as the precursors and were dissolved in n-butyl acetate. The BNdT thin films were deposited at a substrate temperature and reactor pressure of approximately $600^{\circ}C$ and 4.8 Torr, respectively. The microstructure of the layered perovskite phase was observed by XRD and SEM. The remanent polarization value (2Pr) of the BNdT thin film was $31.67\;{\mu}C/cm^{2}$ at an applied voltage of 5 V.

Equi-spaced multichannel stabilization with a reference frequency from ($^13C_2H_2$) molecules and optical fiber fabry-perot filter (아세칠렌가스($^13C_2H_2$)분자의 흡수선을 이용한 기준 광신호 및 광섬유 파브리-페로 필터에 의한 등간격 다중채널의 안정화)

  • 이현재;류갑열;이동호;박창수
    • Korean Journal of Optics and Photonics
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    • v.8 no.1
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    • pp.68-72
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    • 1997
  • Using one of the absorption lines of $^{13}C_2H_2$ molecules near the zero dispersion wavelength(1549.49nm) of dispersion shifted fiber, we stabilized center frequency of an optical fiber Fabry-Perot filter. The free spectral range of the filter is 100 GHz for 100 GHz channel allocation. For equi-spaced three channel multiplexing, channel locking of three DFB-LDs to transmission peaks of the fiber Fabry-Perot filter was tried. To investigate the effect of dithering current applied to each DFB-LD, the change of DFB-LD linewidth was measured.

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PSPICE Modeling and Characterization of Optical Transmitter with 1550 nm InGaAsP LDs (1550 nm InGaAsP LD 광송신회로의 PSPICE 모델 및 광변조 특성 해석)

  • Goo, Yu-Rim;Kim, Jong-Dae;Yi, Jong-Chang
    • Korean Journal of Optics and Photonics
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    • v.22 no.1
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    • pp.35-39
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    • 2011
  • The PSPICE equivalent circuit elements of a 1550 nm InGaAsP laser diode were derived by using multi-level rate equations. The device parameters were extracted by using a self-consistent numerical method for the optical gain properties of the MQW active regions. The resulting equivalent circuit model is also applied to an actual optical transmitter, and its PSPICE simulation results show good agreement with the measured results once the parasitic capacitance due to the packaging is taken into account.

Analysis of thermal characteristic variations in LD arrays packaged by flip-chip solder-bump bonding technique (플립 칩 본딩으로 패키징한 레이저 다이오우드 어레이의 열적 특성 변화 분석)

  • 서종화;정종민;지윤규
    • Journal of the Korean Institute of Telematics and Electronics A
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    • v.33A no.3
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    • pp.140-151
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    • 1996
  • In this paper, we analyze the variations of thermal characteristics of LD (laser diode) arrays packaged by a flip-chip bonding method. When we simulate the temperature distribution in LD arrays with a BEM (boundary element method) program coded in this paper, we find that thermal crosstalks in LD arrays packaged by the flip-chip bonding method increases by 250-340% compared to that in LD arrays packaged by previous methods. In the LD array module packaged by the flip-chip bonding technique without TEC (thermo-electric cooler), the important parameter is the absolute temperature of the active layer increased due cooler), the important parameter is the absolute temperature of th eactiv elayers of LD arrays to thermal crosstalk. And we find that the temperature of the active layers of LD arrays increases up to 125$^{\circ}C$ whenall four LDs, without a carefully designed heatsink, are turned on, assuming the power consumption of 100mW from each LD. In order to reduce thermal crosstalk we propose a heatsink sturcture which can decrease the temeprature at the active layer by 40%.

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Isolation and Partial Characterization of Hemin-binding Cell Envelope Proteins from Porphyromonas gingivalis, Prevotella intermedia, and Prevotella nigrescens (Porphyromonas gingivalis, Prevotella intermedia, 그리고 Prevotella nigrescens에서의 hemin 결합 단백질에 대한 연구)

  • Kim, Sung-Jo
    • Journal of Periodontal and Implant Science
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    • v.36 no.1
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    • pp.155-165
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    • 2006
  • The results of this study confirm that the availability of hemin influences the expression of selected membrane proteins of Porphyromonas gingivalis, Prevotella intermedia, and Prevotella nigrescens. A 30 kDa (heated 24 kDa) hemin-binding protein whose expression is hemin regulated was identified and purified in P. gingivalis. A strong hemin-binding function was found by LDS-PAGE and TMBZ staining when P. gingivalis cells were grown under hemin-limited conditions. A 50 kDa cell envelope associated protein, whose expression is hemin regulated, is considered to be a putative hemin binding protein from P. intermedia and P. nigrescens, respectively. N-terminal amino acid sequence analysis of CNBr-digested 24 kDa hemin binding protein from P. gingivalis revealed that this protein belongs to a new, so far undescribed hemin-binding class of proteins. N-terminal amino acid sequence of a 50 kDa putative hemin binding protein from P. intermedia was identical with Enolase from Streptococcus intermedia. Work is in progress to further characterize the molecular structure of these proteins.

Short Reads Phasing to Construct Haplotypes in Genomic Regions That Are Associated with Body Mass Index in Korean Individuals

  • Lee, Kichan;Han, Seonggyun;Tark, Yeonjeong;Kim, Sangsoo
    • Genomics & Informatics
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    • v.12 no.4
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    • pp.165-170
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    • 2014
  • Genome-wide association (GWA) studies have found many important genetic variants that affect various traits. Since these studies are useful to investigate untyped but causal variants using linkage disequilibrium (LD), it would be useful to explore the haplotypes of single-nucleotide polymorphisms (SNPs) within the same LD block of significant associations based on high-density variants from population references. Here, we tried to make a haplotype catalog affecting body mass index (BMI) through an integrative analysis of previously published whole-genome next-generation sequencing (NGS) data of 7 representative Korean individuals and previously known Korean GWA signals. We selected 435 SNPs that were significantly associated with BMI from the GWA analysis and searched 53 LD ranges nearby those SNPs. With the NGS data, the haplotypes were phased within the LDs. A total of 44 possible haplotype blocks for Korean BMI were cataloged. Although the current result constitutes little data, this study provides new insights that may help to identify important haplotypes for traits and low variants nearby significant SNPs. Furthermore, we can build a more comprehensive catalog as a larger dataset becomes available.