• Title/Summary/Keyword: Fiber optic

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The Study on the Integrated Emergency Management System using Network GR-type Receiver and Control Desk (네트워크 GR형 수신기와 컨트롤데스크를 이용한 통합방재관리시스템에 대한 연구)

  • Baek, Dong-Hyun;Song, Ho-Bin;Kang, Won-Shun
    • Fire Science and Engineering
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    • v.26 no.1
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    • pp.96-101
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    • 2012
  • The buildings of domestic wear the upper floors and an underground in-depth reconciliation tendency to do and the possibility of fire occurrence at the time of formation accident is coming to be high. Therefore will be scattered to various place and is established and prevention of disaster information of the receiver which will integrate there is a necessity which will manage. In this paper away where each receiver is installed in the fire for the remote monitoring and controld able to connect to the Internet and fiber optic cable that can be networked fire receiver and control desk was constructed. Between each device can be used by the fire, and more depending on the status of monitoring and alarm, control and maintenance can be performed to develop an integrated management system. The system is evaluated by the criteria of the KFI, and for each segment of the signal propagation time to perform experiments confirmed the reliability of the performance.

Picture archiving and communications systems development and performance results

  • Nam, Ji-Seung;Ralph Martinez
    • 제어로봇시스템학회:학술대회논문집
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    • 1991.10b
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    • pp.1796-1800
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    • 1991
  • Picture Archiving and Communication Systems(PACS) provide an integration of digital imaging information in a hospital, which encompasses various imaging equipment, viewing workstations, database archive systems, and a high speed fiber optic network. One of the most important requirements for integration is the standardization of communication protocols to connect devices from different vendors. Since 1985, the ACR-NEMA standard provides a hardware interface, a set of software commands, and a consistent set of data formats for point-to-point interconnection of medical equipment. However, it has been shown to be inadequate for PACS networking environments, because of its point-to-point nature and its inflexibility to allow other services and protocols in the future. Based on previous experience of PACS developments in The University of Arizona, a new communication protocol for PACS networks has been suggested to the ACR-NEMA Working Group VI. The defined PACS protocol is intended to facilitate the development of PACS's capable of interfacing with other hospital information systems. Also, it is intended to allow the creation of diagnostic information data bases which can be interrogated by a variety of distributed devices. A particularly important goal is to support communications in a multivendor environment. The new protocol specifications are defined primarily as a combination of the International Organization for Standardization / Open Systems Interconnection (ISO/OSI) protocols and the data format portion of ACR-NEMA standard. This paper addresses the specification and implementation of the proposed PACS protocol into network node. The protocol specification, which covers Presentation, Session, Transport, and Network layers, is summarized briefly. The implementation has natural extentions to Global PACS environments. The protocol implementation is discussed based on our implementation efforts in the UNIX Operating System Environment. At the same time, results of performance evaluation are presented to demonstrate the implementation of defined protocol. The testing of performance analysis is performed on the PACS prototype node.

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STABILIZATION OF REFERENCE SIGNAL TRANSMISSION SYSTEM IN RADIO TELESCOPE FOR VLBI (VLBI 전파망원경 기준 신호 전송시스템 안정화)

  • Je, Do-Heung;Lee, Won-Kyu;Kim, Soo-Yeon;Chung, Moon-Hee;Song, Min-Kyu;Jung, Taehyun;Byun, Do-Young;Kim, Seung-Rae;Sohn, Bong-Won;Wi, Seog-Oh;Han, Seog-Tae;Kang, Yong-Woo
    • Publications of The Korean Astronomical Society
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    • v.28 no.3
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    • pp.95-100
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    • 2013
  • A fiber-optic reference signal transmission system, which transmits the 1.4 GHz reference signal from H-maser to receiver cabin in radio telescopes, was adopted for compensating the phase changes due to temperature variation and antenna movement. At the first experiment, the remote signal's phase changed more than 15 degrees at 1.4 GHz. We found unstable components in sub-system experiments and replaced them. The main cause of unstable phase stability was the unaligned polarization axis between Laser Diode and Mach-Zehnder Modulator (MZM). The improved system stability showed $1{\times}10^{-16}$ allan standard deviation at 1,000 sec integration time with the antenna fixed. When the antenna moves in the azimuth axis, the 1.4 GHz remote signal showed the phase change smaller than 0.2 degrees.

Development of Biomolecular Device Using Biomolecular Film Part 1: Optical Biosensor to Detect the Ethanol Using Langmuir-Blodgett Film of Eilzyme Molecules (생체분자막을 이용한 생물분자소자의 개발 제1부 :효소분자 LB막을 이용한 에탄올 측정용 광학 바이오센서)

  • 최정우;배주연지용이원홍
    • KSBB Journal
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    • v.10 no.1
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    • pp.105-112
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    • 1995
  • The fiber-optic biosensor using enzyme-immobilized Langmuir-Blodgett film is developed fort the measurement of ethanol. The enzyme, alcohol dehydrogenase, is immobilized at the molecular level on the arachidic acid monolayer using Langmuir-Blodgett film technique. Based on the ordered multisubstrate mechanism, the immobilized enzyme kinetics is investigated. The optical sensing system is proposed, and sensor signal is proportional to ethanol concentration and is related wish the number of enzyme layers. As the number of deposited LB film layer increases up to 20 1ayers, the high ethanol concentration of 45mM can be measured without the saturation of signal. Surface pressure-area isotherm is measured for the three-different charged-lipids. Arachidic acid is the most suitable for the adsorption of alcohol dehydrogenase based on electrostatic force.

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Development of accuracy for the statical inclinometer by error analysis (다축 수준기의 오차분석을 통한 측정 정밀도 향상)

  • Lee J.K.;Park J.J.;Cho N.G.
    • Proceedings of the Korean Society of Precision Engineering Conference
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    • 2005.06a
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    • pp.1797-1802
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    • 2005
  • In this study, we were developed an accuracy of the proposed two dimensional statical inclinometer what used a position sensitive detector(PSD) by an error analysis. The inclinometer consists of a laser source, a mass, an optic-fiber, and a PSD. The gravity direction on a base platform of the inclinometer is changed by an unknown inclination angle. And a laser spot is moved from the origin to another position of a PSD following a variation of an optical path by the gravity. These processes enable the inclinometer to estimate the inclination angle from distance information of the moving spot. A design methodology on the basis of a sensitivity analysis was applied to improve the measurement performance such as a full measuring range and a resolution. But it still has error factors, so we analyze the uncertainty of the inclinometer to evaluate the systematic errors from alignments, assembly error and so on. The experimental performance evaluation about the design objectives as a measuring range and a resolution was performed. And the validity and the feasibility of the design process were certified by an experimental process. Systematic errors eliminated to improve the accuracy of the inclinometer by the corrected measuring model from the calibration process between the inclination angle and the PSD position instead of the nominal measuring model. The ANOVA(analysis of variance) confirmed the effect of eliminating the systematic errors in the inclinometer. From these methodologies, the proposed inclinometer was able to measure with a high resolution(35.14sec) and a wide range(from $-15^{\circ}\;to\;15^{\circ}$

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QUICK DETERMINATION OF MEAT COLOR, METMYOGLOBIN FORMATION AND LIPID OXIDATION IN BEEF, PORK AND CHICKEN BY NEAR-INFRARED SPECTROSCOPY

  • Mitsumoto, Mitsuru;Sasaki, Keisuke;Murakami, Hitoshi
    • Proceedings of the Korean Society of Near Infrared Spectroscopy Conference
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    • 2001.06a
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    • pp.1259-1259
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    • 2001
  • Meat becomes brown and rancid during storage in the refrigerator and display in the case. Color changes, metmyoglobin formation and lipid oxidation are the important problems in the transportation / distribution of meat and retail display. The freshness of meat is determined by the sense of vision and smell. Since conventional method determining lipid oxidation is time consuming and destructive (it needs to homogenize meat with reagents, filtrate, time for reaction and read optical density using spectroscopy), more rapid and nondestructive technical tools are desired. The objective of this work was to evaluate near-infrared spectroscopy as an analytical tool for determining meat color, metmyoglobin formation and lipid oxidation. in beef, pork and chicken. Semitendinosus and longissimus thoracis muscles from six beef steers, biceps femoris and longissimus thoracis muscles from twelve LWD crossbred pigs, and superficial pectoral muscles from twenty-four broilers were used. About a 5-cm diameter and 1-cm thick sample (20.0g) was cut from the muscle and placed on plastic foam, over-wrapped with PVC film, and displayed under flourescent lights at 4 degrees C. during 10 days for beef and pork or 4 days for chicken. The spectra was measured by NIR systems Model 5500 Spectrophotometer using fiber optic scan at range of 400 - 1100 nm. Data were recorded at 2 nm intervals and 10 scans / 10 sec were averaged for every sample. Data obtained were saved as log 1/Re, where Re is the reflectance energy, and then mathematically transformed to second derivatives to reduce effects of differences in particle size. $L^{*}$, $a^{*}$ and $b^{*}$, and metmyoglobin formation were determined by conventional spectrophotometer using the integrating sphere unit. 2-Thiobarbituric acid reactive substances (TBARS) were measured for lipid oxidation. A multiple linear regression was used to find the equation which would best fit the data. The number of wavelengths used in the equation was selected based on the fewer number compared to the increasing multiple correlation and Decreasing standard error. (omitted)

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A Phase Stabilization System of EFPI for Damage Detection of Composite (복합재료 파손 검출을 위한 EFPI 센서 위상 안정화 시스템)

  • Kim,Dae-Hyeon;Gu,Bon-Yong;Bang,Hyeong-Jun;Kim,Cheon-Gon;Hong,Chang-Seon
    • Journal of the Korean Society for Aeronautical & Space Sciences
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    • v.31 no.8
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    • pp.44-49
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    • 2003
  • In case of an extrinsic Fabry-Perot interferometric sensor, the phase compensating technique is particularly necessary in applying the interferometer to detecting acoustic emission signals because of signal-fading problems. The technique makes it possible to maintain the phase at the quadrature point. In this paper, we developed the stabilization control sensor system that is composed of a broadband light source, a tunable Fabry-Perot (F-P) filter and a control-circuit board. A tension test of a composite specimen was performed to verify if the developed system could compensate the phase change induced from the tension strain and keep the phase at the quadrature point.

Detection of fluorescence from soils contaminated with monoaromatic hydrocarbons (유류 오염 토양에서의 단일방향족 탄화수소 농도 측정을 위한 자외선 형광 분석에 관한 연구)

  • 김우진;박재우;이주인
    • Journal of Soil and Groundwater Environment
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    • v.7 no.2
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    • pp.35-44
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    • 2002
  • In order to determine the contamination of the aromatic hydrocarbons in soil, a fiber-optic sensing technique with fluorescence detector has been proposed. Previous researches have shown that the optimal condition for detecting benzene, toluene, ethylbenzene, xylene (BTEX) was 260 nm /290 nm (excitation/emission wavelength). However, broader fluorescence spectra of BTEX-polluted soil sample ranging from 300 nm to 600 nm were observed. Additionally, the intensity of fluorescence increased with increasing BTEX concentration, which was conspicuous in the fine-particle soil, The overall results indicated that the suggested technique could be useful for in-situ monitoring system for subsurface oil-storage tank.

Arthroscopic Findings of the Canine Stifle Joint (정상견 무릎의 관절경 검사소견)

  • 정순욱;정월순
    • Journal of Veterinary Clinics
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    • v.16 no.2
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    • pp.300-308
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    • 1999
  • Arthroscopy is a valuable diagnostic and operative tool in equine and human orthopedics. The arthroscope is a difficult instrument to use and requires patience, practice, and persistence in order to obtain good results. This technique was found to be less traumatic than arthrotomy, invasiveness, rapid recovery and the feasibility of surgically correcting many arthropathies. The use of the arthroscope in the dog provides a new dimension in the study and diagnosis of joint derangements. The purpose of this report is to introduce the use of the arthroscope in the dog-more specifically, in the stifle of the dog. A diameter 2.7 mm fore-oblique viewing arthroscope, cold light source, video and video printer are used. With the fore-oblique viewing type it is possible to view directly as well as slightly to the side and the range of viewing can be increased by rotating the arthroscope around the object The scope is connected with a cold light source by means of a fiber-optic light guide. The stifle joint was flexed to 20~30$^{\circ}$. The joint were lavaged with lactated Ringer's solution during arthroscopic examination. Arthroscopy of the stifle was performed prior to arthrotomy in 1 dead dog and 4 healthy dogs, and other 3 dogs was performed only arthroscopic examination. In this study only the conventional approaches were used and in most cases it was possible to view all the intra-articular structures via the lateral infrapatellar approach. In the stifle joint, endoscopic observation was performed to find lateral femoral condyle, patella, medial femoral condyle, trochlear groove, tibia, fat, cranial cruciate ligament, caudal cruciate ligament lateral meniscus, tendon of long digital extensor muscle, medial meniscus, and medial collateral ligament Post-arthroscopic examination, the lameness had disappeared within 12~24 hours. Pain and swelling in the stifle joint had disappeared within 24~36 hours. Post-arthroscopic secondary infection was never encountered in the dogs. In conclusion, arthroscopic insertion technique in canine stifle joint using a diameter 2.7 mm 30$^{\circ}$ arthroscope was established and arthroscopical views of all anatomical structures in the normal stilfe joint were obtained through lateral infrapatellar portal.

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Development of TDMA-Based Protocol for Safety Networks in Nuclear Power Plants (원전 안전통신망을 위한 TDMA 기반의 프로토콜 개발)

  • Kim, Dong-Hoon;Park, Sung-Woo;Kim, Jung-Hun
    • The Transactions of the Korean Institute of Electrical Engineers D
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    • v.55 no.7
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    • pp.303-312
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    • 2006
  • This paper proposes the architecture and protocol of a data communication network for the safety system in nuclear power plants. First, we establish four design criteria with respect to determinability, reliability, separation and isolation, and verification/validation. Next we construct the architecture of the safety network for the following systems: PPS (Plant Protection System), ESF-CCS (Engineered Safety Features-Component Control System) and CPCS (Core Protection Calculator System). The safety network consists of 12 sub-networks and takes the form of a hierarchical star. Among 163 communication nodes are about 1600 origin-destination (OD) pairs created on their traffic demands. The OD pairs are allowed to exchange data only during the pre-assigned time slots. Finally, the communication protocol is designed in consideration of design factors for the safety network. The design factors include a network topology of star, fiber-optic transmission media, synchronous data transfer mode, point-to-point link configuration, and a periodic transmission schedule etc. The resulting protocol is the modification of IEEE 802.15.4 (LR-WPAN) MAC combined with IEEE 802.3 (Fast Ethernet) PHY. The MAC layer of IEEE 802.15.4 is simplified by eliminating some unnecessary (unctions. Most importantly, the optional TDMA-like scheme called the guaranteed time slot (GTS) is changed to be mandatory to guarantee the periodic data transfer. The proposed protocol is formally specified using the SDL. By performing simulations and validations using Telelogic Tau SDL Suite, we find that the proposed safety protocol fits well with the characteristics and the requirements of the safety system in nuclear power plants.