• Title/Summary/Keyword: System A/C

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Performance Analysis of Quasi-synchronous MC-CDMA and MC-DS/CDMA in Mobile Satellite Return Link (이동위성 리턴링크에서 준동기 MC-CDMA와 MC-DS/CDMA 성능 분석)

  • 안치훈;최영관;이호진;김동구
    • Journal of the Institute of Electronics Engineers of Korea TC
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    • v.40 no.8
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    • pp.307-317
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    • 2003
  • We analyze the performance of MC-CDMA and MC-DS/CDMA system on quasi-synchronized moble satellite return link. Quasi-synchronization is considered that chip offset between terminals is within a few chips. In 10-3 BER, performance of MC-DS/CDMA system with walsh code is 0.3dB better than that of MC-CDMA system when the number of user is 5 from -0.5 $T_{c}$ to 0.5 $T_{c}$ quasi-synchronization of MC-DS/CDMA system and from -5/64 $T_{c}$ $^{MC}$ to 5/64 $T_{c}$ $^{MC}$ quasi-synchronization of MC-CDMA system. MC-DS/CDMA system with walsh code is over 0.2dB better than that of MC-DS/CDMA system with extended m code and gold code. MC-CDMA system with walsh code is over 1.2dB better than that of MC-CDMA system with gold code when the number of user is 5 and lower than from -5/32 $T_{c}$ $^{MC}$ to 5/32 $T_{c}$ $^{MC}$ quasi-synchronization.

C-PLM: Design and Implementation of a PLM System for Effective Management of Civil Projects (C-PLM: 토목 프로젝트 관리를 위한 PLM 시스템 설계 및 구축)

  • Kang, Hyoung-Seok;Lee, Sang-Seok;Noh, Sang-Do;Lee, Kwang-Myoung
    • Korean Journal of Computational Design and Engineering
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    • v.15 no.2
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    • pp.124-135
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    • 2010
  • PLM(Product Lifecycle Management) is one of innovative manufacturing paradigms which leverages e-business technologies to allow a company's product content to be developed and integrated with all company business process through the extended enterprise. In these days, most construction companies also make an effort to enhance their systems for creating, sharing and managing information to improve business efficiency through entire lifecycle of project execution. Because of different needs, business process and diverse engineering activities such as design, structural analysis, installing simulation, documents and data managements, a new paradigm for construction companies is needed to manage and share the entire workflow, and information in total project lifecycle. In this paper, we conducted user requirement and business process analysis of constructions to design C-PLM system which is a PLM system for effective management of civil project and engineering activities. Also, we implement C-PLM system based on commercial PDM system, and applied it to civil project as case studies.

Correlation on Compressor Discharge Temperature of System A/C using PWM Compressor in Heating Mode (PWM 압축기를 이용한 시스템에어컨의 난방운전 시 압축기 토출온도 상관식)

  • Lee, S.H.;Kwon, Y.C.;Chang, K.S.;Heo, S.H.;Kim, D.H.;Youn, B.
    • Proceedings of the SAREK Conference
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    • 2006.06a
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    • pp.1095-1100
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    • 2006
  • An experimental study has been performed to investigate the correlation on compressor discharge temperature of system A/C in heating mode. Indoor and outdoor temperatures, the heating capacity, compressor discharge temperature and loading time are measured by the psychrometric calorimeter. The system is controlled by applying the scroll compressor, which Is operated by PWM valve and loading duty. With increasing outdoor temperature, the heating capacity increases, With increasing indoor temperature, it decreases. Also, with increasing loading duty the heating capacity increases. According to the increase in outdoor temperature and loading duty, compressor discharge temperature increases. From these experimental data, the correlation on compressor discharge temperature is proposed. It is expressed as a function of indoor temperature, outdoor temperature, and loading duty. The correlation obtained from the present study is agreed with the experimental data within $2^{\circ}C$.

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Edge Camera based C-ITS Pedestrian Collision Avoidance Warning System (엣지 카메라 기반 C-ITS 보행자 충돌방지 경고 시스템)

  • Park, Jong Woo;Baek, Jang Woon;Lee, Sangwon;Seo, Woochang;Seo, Dae-Wha
    • The Journal of The Korea Institute of Intelligent Transport Systems
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    • v.18 no.6
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    • pp.176-190
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    • 2019
  • The prevention of pedestrian accidents in crosswalks and intersections is very important. The C-ITS services provide a warning service for preventing accidents between cars and pedestrians. In the current pedestrian collision prevention warning service according to the C-ITS standard, however, it is difficult to provide real-time service because it detects pedestrians from a video-analysis server in the control center and sends service messages through the ITS system. This paper proposes a pedestrian collision-prevention warning system that detects pedestrians in the local field using an edge camera and sends a warning message directly to the driver through a roadside unit. An evaluation showed that the proposed system could deliver the pedestrian collision prevention-warning message to the driver satisfying the delay time within the 300 ms required by the C-ITS standard, even in the worst case.

High-Speed Active Vibration Control System of Plate using TMS320C6713DSK (TMS320C6713DSK를 적용한 평판의 고속 능동 진동제어)

  • Choi, Hyeung-Sik;Her, Jae-Gwan;Seo, Hae-Yong
    • Journal of Advanced Marine Engineering and Technology
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    • v.33 no.6
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    • pp.918-924
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    • 2009
  • This paper deals with the experimental assessment of the vibration suppression of the smart structures. First, we have presented the paper about the new high-speed active control system that we have developed using the DSP320C6713 microprocessor and a peripheral system composed of a data acquisition system, A/D and D/A converters, piezoelectric (PZT) actuator/sensors, and drivers using PA95. Since fast data processing is very important in the active vibration control of the structures, we utilized the fast processing DSP320C6713 microprocessor as a main processor to the controller and fast peripheral devices for fast control loop. To realize a fast active vibration control, we have analyzed and tested the processing time of the peripheral devices and provided the corresponding test results. Especially, we have focused on achieving the fast signal amplification of the PA95 device since it takes most of loop times of the control system. Finally, we performed numerous experiments of active vibration control of the aluminum plate to validate the superior performance of the developed control system based on previous mode tests of the plate.

Identification of Uncommon Candida Species Using Commercial Identification Systems

  • Kim, Tae-Hyoung;Kweon, Oh Joo;Kim, Hye Ryoun;Lee, Mi-Kyung
    • Journal of Microbiology and Biotechnology
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    • v.26 no.12
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    • pp.2206-2213
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    • 2016
  • Recently, several studies have revealed that commercial microbial identification systems do not accurately identify the uncommon causative species of candidiasis, including Candida famata, Meyerozyma guilliermondii, and C. auris. We investigated the accuracy of species-level identification in a collection of clinical isolates previously identified as C. famata (N = 38), C. lusitaniae (N = 1 2), and M. guilliermondii (N = 5) by the Vitek 2 system. All 55 isolates were re-analyzed by the Phoenix system (Becton Dickinson Diagnostics), two matrix-assisted laser desorption ionization-time of flight mass spectrometry analyzers (a Vitek MS and a Bruker Biotyper), and by sequencing of internal transcribed spacer (ITS) regions or 26S rRNA gene D1/D2 domains. Among 38 isolates previously identified as C. famata by the Vitek 2 system, the majority (27/38 isolates, 71.1%) were identified as C. tropicalis (20 isolates) or C. albicans (7 isolates) by ITS sequencing, and none was identified as C. famata. Among 20 isolates that were identified as C. tropicalis, 17 (85%) were isolated from urine. The two isolates that were identified as C. auris by ITS sequencing originated from ear discharge. The Phoenix system did not accurately identify C. lusitaniae, C. krusei, or C. auris. The correct identification rate for 55 isolates was 92.7% (51/55 isolates) for the Vitek MS and 94.6% (52/55 isolates) for the Bruker Biotyper, as compared with results from ITS sequencing. These results suggest that C. famata is very rare in Korea, and that the possibility of misidentification should be noted when an uncommon Candida species is identified.

Design of Architecture for Collaborative Project Management System based on Business Process (프로세스 기반의 협업 프로젝트 관리 시스템 구조 설계)

  • Baek, Jae-Yong;Jung, So-Young;Kim, Bo-Hyun;Yoo, Seock-Kyu;Lee, Seok-Woo;Choi, Hon-Zong
    • Korean Journal of Computational Design and Engineering
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    • v.14 no.5
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    • pp.338-345
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    • 2009
  • c-PMS(collaborative project management system) is a business process(BP) based tool to manage collaborative projects which accomplish common business objectives determined by mutual agreement of companies using limited resources and time. This study analyzes collaborative BP, collaborative projects, and their relation, and proposes the architecture and operation scenario of c-PMS consisted of business process asset management(BPAM) sub-system and project manage(PM) sub-system. BPAM sub-system models private and public BP using a client/server based modeler, defines collaborative BPs process from public BPs, and manages them as companies' asset on a web portal. PM sub-system globally manages collaborative project using planning, execution, monitoring, and analyzing functions.

Robot vision interface (로보트와 Vision System Interface)

  • 김선일;여인택;박찬웅
    • 제어로봇시스템학회:학술대회논문집
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    • 1987.10b
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    • pp.101-104
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    • 1987
  • This paper shows the robot-vision system which consists of robot, vision system, single board computer and IBM-PC. IBM-PC based system has a great flexibility in expansion for a vision system interfacing. Easy human interfacing and great calculation ability are the benefits of this system. It was carried to interface between each component. The calibration between two coordinate systems is studied. The robot language for robot-vision system was written in "C" language. User also can write job program in "C" language in which the robot and vision related functions reside in the library.side in the library.

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1H Nuclear Magnetic Resonance of a Ferroelectric Liquid Crystalline System

  • Cha, J.K.;Lee, K.W.;Oh, I.H.;Han, J.H.;Lee, Cheol-Eui;Jin, J.I.;Choi, J.Y.
    • Journal of Magnetics
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    • v.15 no.2
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    • pp.61-63
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    • 2010
  • We used $^1H$ nuclear magnetic resonance (NMR) to study the phase transitions and molecular dynamics in a characteristic ferroelectric liquid crystal with a carbon number n = 7, S-2-methylbutyl 4-n-heptyloxybiphenyl-4'-carboxylate (C7). The results were compared with those of our recent work on S-2-methylbutyl 4-n-octanoyloxybiphenyl-4'-carboxylate (C8), with a carbon number n = 8. While the recrystallization and isotropic phase transitions exhibited a first-order nature in the $^1H$ NMR spin-lattice and spin-spin relaxation measurements, a second-order nature was shown at the Sm-A - Sm-$C^*$ liquid crystalline phase transition. A soft-mode anomaly arising from the tilt angle amplitude fluctuation of the director, of which only a hint had been noticed in the C8 system, was manifested in the C7 system at this transition.

Effect of Organic Admixture(Calcium Lignosulfonate) (I) on the Early Hydration Process of Protland Cement (시멘트 초기 수화과정에 대한 유기혼화제의 영향(I))

  • 문정연;최상홀
    • Journal of the Korean Ceramic Society
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    • v.21 no.2
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    • pp.143-148
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    • 1984
  • In this study we mainly dealt with the effects of organic retarder(calcium lignosulfate) on the early hydration process of clinker minerals. From a consideration of the hydration process of tricalcium silicate $(C_3S)$ tricalcium silicate $(C_3S)$-tricalcium aluminate $(C_3A)$ tricalcium silicate $(C_3S)$-tetracalcium aluminof-errite $(C_4AF)$ systems with calcium lignosulfate the following results were obtained. 1. when 0.25wt% of CLS was added to $C_3S$ the hydration process was progressed normally but adding of 0.5wt% its hydration was greatly retarded. 2. The hydration of $C_3S$-$C_3A$ system was progressed normally up to 0.5wt% but by adding gypsum its hydration was retarded slightly. 3. The hydration of $C_3S$-$C_4AF$ system was greatly retarded even with 0.25wt% of CLS but by adding gypsum its hydration process was recovered normally.

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