• Title/Summary/Keyword: ARI

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Evaluation of energy efficiency ratio in the mixed air conditioner system (혼합 공조 시스템의 EER(A) 평가)

  • 김병순;이승홍
    • Korean Journal of Air-Conditioning and Refrigeration Engineering
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    • v.11 no.4
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    • pp.542-548
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    • 1999
  • Instead of testing split air conditioners, an empirically based calculation procedure may be used to estimate the Energy Efficiency Ratio at ARI A test conditions. Typically, the system involving the indoor unit well sold and the given outdoor unit is called the matched system. All other systems involving a given outdoor unit and other indoor units are called the mixed systems. To estimate the EER(A) for the mixed systems, EER(A) for the matched system must be known, Generally, the EER(A) for the matched system is known. This procedure relies on independent measurements and calculations made on an outdoor unit in conjunction with a matched indoor and a mixed indoor coil. A heat pump simulation model was used to quantify the effects of individual system components on the system performance. The procedure is applicable to all air-conditioning units having rated cooling capacities less than 19,000W and charged with refrigerant 22.

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Wet Surface Performance Test of PF Heat Exchanger (PF열교환기의 습표면 성능시험)

  • Cho, J.P.;Kim, N.H.;Choi, K.K.
    • Proceedings of the KSME Conference
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    • 2000.11b
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    • pp.314-320
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    • 2000
  • In this study, the wet surface heat transfer coefficients and friction factors of PF heat exchangers are presented. Two sample with different fin pitch(1.25mm, 1.5mm) were tested. Tests were conducted in a open loop wind tunnel. The wet surface heat transfer coefficient was reduced following the procedure given in ARI 410-81. Results showed that the heat transfer coefficients of the heat exchanger with 1.5mm fin pitch were approximately the same as those with 1.25mm fin pitch, except at low reynolds number(Re<100), where the heat transfer coefficients of 1.5mm fin pitch were slighly higher than those with 1.25mm fin pitch. The friction factors of the 1.25mm fin pitch, however was 120 % to 160 % higher than those of the 1.5mm fin pitch. The wet surface heat transfer coefficients were lower than those of the dry surface. The wet surface friction factors, however, were higher than those of the dry surface.

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Detection of Laser excited Lamb-wave using Air-coupled Transducer and Identification of Propagation Mode using Wavelet Transform (공기-결합 트랜스듀서를 이용한 레이저 여기 램파의 검출과 웨이브렛 변환을 이용한 전파모드 규명)

  • Kim, Hyun-Mook;Kim, Hong-Jun;Jhang, Kyung-Young;Lee, Jun-Hyun
    • Proceedings of the KSME Conference
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    • 2003.04a
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    • pp.851-856
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    • 2003
  • This paper proposes a single-mode Lamb-wave generation and detection system using a pulsed laser as a generator and an air-coupled transducer combined with the wavelet transform analysis, as the detector. The laser source with arrayed linear slits was used to generate Lamb-wave which is able to control the wavelength of Lamb-wave to be generated by changing the slits separation. An ari-coupled transducer was used to receive Lamb-wave, which can selectably receive a single mode of leaky Lamb wave by changing the oblique angle of transducer, since the leaky Lamb-wave has unique leaky-angle according to the mode. Also, the received signal was processed by wavelet transform for the analysis in domain of time-frequency. The theoretical dipersion curve and the experimetal result was compared to show good agreement.

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Analysis of Operational Status and Effectiveness of Single-Track Accredited Program in ABEEK (공학교육인증의 단일인증프로그램 운영실태 및 효과분석)

  • Han, Jiyoung
    • Journal of Engineering Education Research
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    • v.23 no.4
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    • pp.66-75
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    • 2020
  • This study was conducted using the literature review and survey research to analyze the operational status and effectiveness of the single-track accredited program, which has been mandatory since 2016. The research targets to achieve the purpose of the study were the nationwide engineering education accreditation system operating colleges, departments, and engineering education innovation centers. Finally, 183 copies were collected from faculty members at 69 colleges and 554 copies at the department level. As a result of the survey, the college recognized more positively about the operation of the single-track accredited program, and more than 50% of respondents said that there were difficulties due to the operation of the system. The contents required were analyzed and presented. Based on this, the engineering education accreditation system, including the single-track accredited program, suggested the direction of support at the government level and the ABEEK level to better settle down in the field of engineering colleges.

Performance Certification Program for GSHP in Korea (지열원 열펌프 유닛의 시험 및 성능인증 기준 조사분석)

  • Woo, Jeong-Tae;Yun, Jae-Ho;Kang, Hee-Jeong;Kim, Jong-Ha;Choi, Youn-Sung;Kim, Min-Jun
    • 한국신재생에너지학회:학술대회논문집
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    • 2007.11a
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    • pp.519-524
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    • 2007
  • In this study, NR GT 101 (water-to-water Ground source heat pump unit) and NR GT 102 (water-to-air Ground source heat pump unit) related with ISO and ARI guideline were introduced and researched. GSHPs testing was performed by NR GT 101, 102 and analyzed performance factors. Test result, Energy Efficiency Ratio and Coefficient of performance factor of GSHPs were relatively low at an average value rather than Certification.

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Biosensors for On-the-spot Detection of Bacteria from Foods (식품 유래 박테리아 현장검출용 바이오센서)

  • Lee, Won-Il;Kim, Bo-Yeong;Son, Young-Min;Kim, Ari;Lee, Nae-Eung
    • Journal of Sensor Science and Technology
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    • v.25 no.5
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    • pp.354-364
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    • 2016
  • Recently there have been extensive research activities on the development of on-the-spot detection technologies for bacteria from foods due to growing high demand for food safety. In particular, on-the-spot detection devices using biosensors with rapid, highly sensitive and multiplexed sensing capability are promising for portable or mobile applications. Firstly, issues related to on-the-spot bacteria detection are discussed. Then, detection methods for bacteria, types of biosensors depending on transducing principle and receptors, and platforms for integration of biosensors and signal readers are reviewed. Finally, prospects for development of on-the-spot detection devices are summarized.

KOREAN STANDARD OF POSNERO-ANTERIOR CEPHALOGRAPHY (P-A Cephalography에 의한 한국인 기준치에 관하여)

  • Ahn Hyung Kyu
    • Journal of Korean Academy of Oral and Maxillofacial Radiology
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    • v.4 no.1
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    • pp.11-20
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    • 1974
  • The author conducted an experiment using P-A Cephalography of 242 male and female subjects of ages ranging 2-6, 7-15, and adult group. By means of Nakago's method of measurement, the standard value of Korean was obtained. The results were as follows; 1. In the group of an age, the male value was greater slightly than female value. 2. In each age group the difference between the right and left widths could be recognizable, however, it was not much great. 3. In each group, regardless of sex, the growth relation was clearly distinguishable at PO, ARI, ARE, MG, AG, and CAW. 4. When the standard value of adult Korean was compared with that of Japanese, Japanese was great with respect to the width of maxillary portion and Korean was great with respect to the width of mandibular portion. 5. Maximum head width of white man was almost similar to that of Korean, however, maxillary alveolar base width of white man was considerably small or the dental arch was narrow.

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Design of LMI-Based H$\infty$ Controller for Robot Manipulators

  • Park, Kwang-Sung;Park, Yoon-Ho;Park, Jin-Bae
    • 제어로봇시스템학회:학술대회논문집
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    • 1998.10a
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    • pp.151-156
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    • 1998
  • In this paper, we present new control method for robot manipulators. The design objective can be the implementation of minimax controller with H$_{\infty}$ performance via LMI approach to guarantee the robustness and to obtain the exact tracking performance for robot manipulators with system parameter uncertainty and exogenous disturbance. We show that the Algebraic Riccati equation (ARE) which is needed for the construction of H$_{\infty}$ controller can be recast into the Algebraic Riccati Inequality (ARI) and the optimal control gain can be obtained by convex optimization method. Then, we will apply the proposed controller to rigid robot manipulators for verifying the performance of our controller.

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