• Title/Summary/Keyword: Qmax

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Fatigue and Sensorial Properties of Commercially Available Brassiere Wing Materials (시판 브래지어 날개 소재의 피로도 및 질감에 관한 연구)

  • 한은경;신정원;홍경희;김은애
    • Journal of the Korean Society of Clothing and Textiles
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    • v.27 no.11
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    • pp.1291-1299
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    • 2003
  • In order to design the better brassiere in terms of appearance and functions, various parameters of the materials should be considered; in this study, fatigue properties and subjective sensation of wing materials and its relation to the preference for a brassiere was investigated. After the survey of commercially available products, five elastic fabrics such as cotton, Modal, polyester, nylon, and Tactel, all of which contain 10% polyurethane, were chosen as specimens. Fabric growth were determined to evaluate fatigue properties. Qmax was determined to evaluate the warm-cool feeling. For the sensory test, semantic differential scale which contains 15 adjectives were developed. Fatigue properties were very similar at the 20% elongation irrespective of the duration of tension, but at 40% and 100% elongation, man made fabric showed less growth than cellulose fabrics. The factor analysis showed four factors such as sense of warmth, smoothness, weight and elasticity. Preference of the specimens was ranked in the order of Tactel>Modal>cotton>nylon>polyester.

Evaluation of Insulation Diagnostic Test Reliability for Stator Winding of High Voltage Induction Motor (고압유도전동기 절연특성시험의 신뢰도 평가)

  • Lee, Kwang-Ho;Kim, Hyun-Il;Kwak, Hee-Jin;Oh, Bong-Keun
    • Proceedings of the KIEE Conference
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    • 2004.11d
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    • pp.46-49
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    • 2004
  • This test was performed to assess the correlation between insulation diagnostic tests and breakdown voltage strength of the stator winding of 6.6kV class induction motor in insulation deterioration condition which have been in service for 5 years after being installed in 1998. The insulation diagnostic tests include resistance, polarization index(P.I), dissipation factor(${\Delta}tan{\delta}$). maximum partial discharges(Qmax) and AC breakdown test. we evaluated the correlation between insulation diagnostic test and AC breakdown test for stator winding of high voltage induction motor.

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A study on insulation characteristics with AC Breakdown Test for Stator Winding of 3.3kV class Induction Motor (절연파괴시험을 통한 3.3kV 유도전동기의 절연특성 연구)

  • Lee, Dong-Geun;Lee, Kwang-Ho;Choi, Kyo-Nam;Kim, Hyun-Il;Kwak, Hee-Jin;Oh, Bong-Keun
    • Proceedings of the KIEE Conference
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    • 2005.07c
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    • pp.2118-2122
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    • 2005
  • This test was performed to assess the corelation of insulation deterioration condition with breakdown voltage of the stator winding of 3.3kV class induction motors which have been in service for 10 years after being installed in 1993. The insulation diagnostic tests include resistance, polarization index(P.I), dissipation factor$({\Delta}tan{\delta})$, maximum partial discharges (Qmax) and AC breakdown test. we evaluated the corelation of insulation diagnostic test with AC breakdown test for stator wilding of high voltage induction motor.

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Evaluation of Insulation Condition for High Voltage Induction Motor (고압유도전동기의 절연상태 평가)

  • Lee, Kwang-Ho;Lim, Jae-Il;Kim, Ki-Won;Jung, Jin-Dal;Lee, Eun-Woong
    • Proceedings of the KIEE Conference
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    • 2003.07b
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    • pp.783-785
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    • 2003
  • This test was performed to assess the insulation deterioration condition of the stator winding of 3.3kV class induction motors which have been in service for 15 years after being installed in 1988. The insulation diagnostic tests include resistance, polarization index(P.I). dissipation factor(${\Delta}tan{\delta}$) and maximum partial discharges(Qmax). The results of diagnostic tests were compared to the visual inspection in overhaul.

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Development of On-Line Partial Discharge Monitoring System in High Voltage Motors (고압전동기 운전중 부분방전 감시 시스템 개발)

  • Kim, Hee-Dong;Kong, Tae-Sik;Ju, Young-Ho
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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    • 2004.07b
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    • pp.1175-1178
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    • 2004
  • On-line partial discharge(PD) monitoring system has been developed to monitor in operating large motor stator insulations. This system makes use of remote diagnosis techniques for the evaluation of PD activity in the control center of thermal power plant. This system can be remotely accessed via a modem to build database, analyze status and interpret the pattern of PD activity. A personnel computer is generally connected to ten motors to continuous measurement of the PD activity. The test data can be easily interpreted by a maintenance staff. For assessing the condition of stator winding in motors, this system ensures a reliable measurement and accurate estimation. Capacitive couplers used for on-line PD measurement have been 80pF. The maximum PD magnitude(Qmax), PD pattern and normalized quantity number(NQN) were performed by this system.

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Flow analysis of the Sump Pump (흡수정의 유동해석)

  • Jung, Han-Byul;Noh, Seung-Hee
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.18 no.3
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    • pp.673-680
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    • 2017
  • sump pump is a system that draws in water that is stored in a dam or reservoir. They are used to pump large amounts of water for cooling systems in large power plants, such as thermal and nuclear plants. However, if the flow and sump pump ratio are small, the flow rate increases around the inlet port. This causes a turbulent vortex or swirl flows. The turbulent flow reduces the performance and can cause failure. Various methods have been devised to solve the problem, but a correct solution has not been found for low water level. The most efficient solution is to install an anti-vortex device (AVD) or increase the length of the sump inlet, which makes the flow uniform. This paper presents a computational fluid dynamics (CFD) analysis of the flow characteristics in a sump pump for different sump inlet lengths and AVD types. Modeling was performed in three stages based on the pump intake, sump, and pump. For accurate analysis, the grid was made denser in the intake part, and the grid for the sump pump and AVD were also dense. 1.2-1.5 million grid elements were generated using ANSYS ICEM-CFD 14.5 with a mixture of tetra and prism elements. The analysis was done using the SST turbulence model of ANSYS CFX14.5, a commercial CFD program. The conditions were as follows: H.W.L 6.0 m, L.W.L 3.5, Qmax 4.000 kg/s, Qavg 3.500 kg/s Qmin 2.500 kg/s. The results of analysis by the vertex angle and velocity distribution are as follows. A sump pump with an Ext E-type AVD was accepted at a high water level. However, further studies are needed for a low water level using the Ext E-type AVD as a base.

A Study on the Adsorptive Removal of Heavy Metals Using Inflated Vermiculites (팽창질석을 이용한 중금속 흡착제거에 관한 연구)

  • Lee, Junki;Koh, Taehoon;Kim, Sukyung;Lee, Taeyoon
    • Journal of the Korean GEO-environmental Society
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    • v.10 no.6
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    • pp.61-68
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    • 2009
  • The main objective of this study was to examine the removal of heavy metals from water by inflated vermiculites. The component of vermiculites was analyzed by XRF, and the concentration of metal ion was measured by ICP-AES. Serial batch kinetic tests and batch sorption tests were conducted to determine the removal characteristics for heavy metals in aqueous solutions. As a result, solution pH values of tests with the inflated vermiculites generally increased and then stabilized. Equilibrium pHs were generally established within 5 hrs. In addition, removal rates of inflated vermiculites were tested at the initial concentration of 3 mg/L. As a result, at equilibrium concentration, except for chromium (36.23%), Most of the heavy metals were effectively removed (96.08~98.54%). Finally, sorption data were correlated with both Langmuir and Freundlich isotherms. The Qmax obtained from Langmuir isotherm were determined to Pb $725.4mg\;kg^{-1}$, Cd $568.8mg\;kg^{-1}$, Zn $540.2mg\;kg^{-1}$, Cu $457.2mg\;kg^{-1}$ Cr $0.9mg\;kg^{-1}$ respectively. The results of the study indicate that inflated vermiculites can be properly used as an adsorbent for various heavy metals because of its outstanding removal rate.

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A Systematic Review of effect on Heat-sensitive Moxibustion for Benign Prostatic Hyperplasia (전립선비대증에 대한 열민구(熱敏灸)의 효과에 관한 체계적 문헌 고찰)

  • Kim, MinSeok;Ju, HongMin;Kim, MinHwa;Park, SunYoung;Yun, YoungJu;Park, SeongHa
    • The Journal of Korean Medicine
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    • v.42 no.3
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    • pp.153-164
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    • 2021
  • Objectives: The aim of this study is to investigate the effect of Heat-sensitive Moxibustion on Benign Prostatic Hyperplasia Methods: We searched articles from Academic Journals(CAJ) online databases, Oriental Medicine Advanced Searching Integrated System (OASIS), Searching key words were '前列腺增生', '熱敏灸' and '열민구', '전립선비대'. The search range included randomized controlled trials (RCTs). Among the articles published to 2020, 10 articles were found. After review the title, abstract and original, 3 articles were selected finally to rule out treatment combined with completely different treatments. Result: The Heat-sensitive moxibustion at acupoints in the treatment of Benign prostatic hyperplasia were significantly superior to control group after treatment in the symptoms of patients, IPSS, QOL, PVR and Qmax(P<0.05). The Heat-sensitive moxibustion can significantly reduce the incidence of temporary urinary incontinence after Transurethral resection of the prostate(TURP) and improve life quality and satisfaction of patients(P<0.05). The individualized desensitization saturated time and amount of Heat-sensitive moxibustion is superior effective to general amount and time of traditional moxibustion in the total effective rate, IPSS, Ru and Qmax(P<0.01) for Benign prostatic hyperplasia. Conclusion: Heat sensitive moxibustion directly transfer heat to the source of a disease. So it can be considered as a good treatment for Benign prostate hypertrophy. It was also shown a better effect on BPH compared to traditional moxibustion, According to the thermo principles of tumor, if the tumor cell's death temperature of 43℃ is reached, that can cause tumor degeneration. Therefore I think Heat sensitive moxibustion can be applied to various tumor disease. The results of this study could be applied to clinical treatment of BPH. However, additional large-scale clinical researches should be conducted.

Heat ,rind Moisture Transfer Properties of Fabrics for Korean Folk Clothes (시판 한복지의 열.수분이동 특성)

  • 성수광;성은정
    • Journal of the Korean Society of Clothing and Textiles
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    • v.20 no.6
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    • pp.1071-1083
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    • 1996
  • This study was carried out to obtain some fundamental data for designing thermally comfortable Korean folk clothes (KFC) which were classified into 4 groups according to seasons and materials. It was conducted to find the relationship among structural, thermal, and moisture transfer properties, and then the properties of heat and mositure transfer while changing thickness of air layer of selected similar fabrics with various thickness were examined. The summarized results of this study were as follows ; 1. The relationship between the structrual and thermal properties showed high positive correlation with thickness SE thermal insulation value (TIV), porosity & TIV. 2. The relationship between the structural and mositure transfer properties showed high negative correlation with thickness & moisture vapor permeability (Mp), porosity & Mp respectively. 3. The relationship between the heat and moisture transfer properites showed high negative correlation with qmax, air permeability (Ap), Mp & TIV while showed high positive with Ap & Mp respectively. 4. Resistance to dry heat transfer according to thickness of air layer for KFC was increassed rapidly up to 2 mm and above this increasing rate was reduced. Resistance to evaporative heat transfer was remarkable changes in 6∼8 mm but slowly in 6∼8 man. 5. Mioisture permeability index (i) according to thickness of air layer for KFC showed the greatest value at 2 mm but had not difference between groups according to thickness.

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Development of Triacetate-containing Functional Coolness Fabrics with Cool-Touch and Cool-Absorbent (접촉 냉감 및 흡수 냉감을 갖는 트리아세테이트 함유 기능성 냉감 직물 개발)

  • Kim, Myoung Ok;Lee, Jung-Soon
    • Journal of the Korean Society of Clothing and Textiles
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    • v.42 no.5
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    • pp.799-808
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    • 2018
  • This study develops triacetate-containing functional fabrics with a cool-touch and cool-absorbent. For this purpose we used composite yarns made using triacetate filament and PET High absorbance quick dry filament as well as the composite fabric woven. The fineness of the yarn and structure of fabric varied the cover factor varied. The blend ratio of triacetate was differently set. When the triacetate content was the same, the cool touch of the fabric having a large cover factor and small SMD increased. The surface became smooth and the contact area became large; in addition, both the Qmax value and the cool-touch became large. In the case of similar density, the cool-touch of the fabric having a large content of triacetate increased. The cool-absorbent of the fabric containing triacetate showed a similar level of the PET High absorbance quick dry filament fabric treated with and endothermic cooling agent. It was possible to develop a functional coolness fabric with a cool-touch and a cool-absorbent when the content of triacetate and cover factor were well combined.