• Title/Summary/Keyword: direct test

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A study on the equivalent circuit test method using Std. IEEE 112 (IEEE 112 등가회로 시험법의 고찰)

  • Lee, I.W.;Ryu, D.W.;Byun, K.B.;Choi, U.K.
    • Proceedings of the KIEE Conference
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    • 2003.10b
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    • pp.63-65
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    • 2003
  • In the case of the large motors which can't direct load tests, IEEE 112 equivalent circuit test was selected instead of the circle diagram method in the newly KEPIC's code. According to the change of code, Hyosung established an equivalent circuit test method based on Standard IEEE 112. In this paper, we compared the test results between IEEE 112 and other standards, CSA C-390, JEC2137 for the large motors.

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The analysis of growth and electrical characteristics of micro-crack with thermal effect in PV module (PV 모듈에서 온도 영향에 의한 micro-crack 성장과 전기적 특성 분석)

  • Song, Young-Hun;Kang, Gi-Hwan;Yu, Gwon-Jong;Ahn, Hyung-Gun;Han, Deuk-Young
    • Proceedings of the KIEE Conference
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    • 2011.07a
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    • pp.1318-1319
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    • 2011
  • In this paper, we analyzed of growth and electrical characteristics of micro-cracks with thermal effect in PV module. The micro-cracks are increasing the breakage risk over the whole value chine from the wafer to the finished module, because the wafer or cell is exposed to mechanical stress. we experimentally analyze the direct impact of micro-cracks on the module power and the consequences after artificial aging. The first step, we made micro-cracks in PV module by mechanical load test according to IEC 61215. Next, PV modules applied the thermal cycling test, because microcracks accelerated aging by thermal cycling test. according to IEC61215. Before every test, we checked output and EL image of PV module.

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Geotechnical Properties of Clay-Fly Ash Mixtures (점토-플라이 애시 혼합물의 지반공학적 특성)

  • Kwon , Moo-Nam;Chung , Sung-Wook;Lee, Sang-Ho;Goo , Jung-Min;Kim , Hyun-Ki
    • Journal of The Korean Society of Agricultural Engineers
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    • v.46 no.5
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    • pp.99-106
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    • 2004
  • Although fly ash has possesses viable engineering properties, an overwhelming majority of fly ash from coal combustion is still placed in storage or disposal sites. This study was undertaken to investigate the physical and mechanical properties of clay-fly ash mixture and to furnish engineering data when fly ash utilized as engineering materials. This paper includes geotechnical properties of fly ash, clay-fly ash mixtures and results of compaction test, unconfined strength test, direct shear test, leaching test and stability analysis of clay-fly ash bank slope. If proper amount of fly ash was put in clay, the clay-fly ash mixture has an increase of unconfined strength and stability of bank slope.

Inhibitory Effects of Medicinal Plants on Anaphylactic Reaction (생약의 아나필락시 반응의 억제 효과)

  • Lee, Jae-Kwan;Yum, Jung-Yul;Kim, Youn-Chul;Shin, Tae-Yong
    • YAKHAK HOEJI
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    • v.44 no.6
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    • pp.489-493
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    • 2000
  • Mortality test has been utilized as a basic method for systemic anaphylactic reaction. Compound 48/80 has been used as a direct and convenient reagent to study the mechanism of anaphylacic reaction. The aqueous extracts of 102 medicinal plants were screened for mortality test using compound 48/80. Sixteen out of the 102 medicinal plants exhibited more than 50% of inhibition on mortality test by their total aqueous extracts with 0.1 mg/g as a final concentration.

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Error Analysis and Compensation for the Volumetric Errors of a Vertical Machining Center Using Hemispherical Helix Ball Bar Test (반구상의 나선형 볼바측정을 통한 수직형 머시닝 센터의 오차 해석 및 보정)

  • Yang, Seung-Han;Kim, Ki-Hoon;Park, YongKuk
    • Journal of the Korean Society for Precision Engineering
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    • v.19 no.9
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    • pp.34-40
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    • 2002
  • Machining accuracy is affected by quasi-static errors of machining center. Since machine errors have a direct influence upon both the surface finish and geometric shape of the finished workpiece, it is very important to measure the machine errors and to compensate these errors. The laser measurement method for identifying geometric errors of machine tool has the disadvantages such as high cost, long calibration time and usage of volumetric error synthesis model. Accordingly, this paper deals with analysis of the geometric errors of a machine tool using ball bar test without using complicated error synthesis model. Statistical analysis method was adopted in this paper for deriving geometric errors using hemispherical helix ball bar test. As a result of experiment, geometric errors of the vertical machining center are compensated by 88%.

Bus Body Rollover Test using Photogrammetry (사진 측량법을 이용한 버스 차체 전복 시험)

  • 정태은;이용래
    • Transactions of the Korean Society of Automotive Engineers
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    • v.5 no.6
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    • pp.28-35
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    • 1997
  • Occupant injuries are always possible in a rollover accident, one of the major accidents in a bus. Thus the structure of body frame should have sufficient strength to protect passengers under accidental loads,. ECE(Economic Commission for Europe) regulation No.66 prescribes that residual space shall be preserved in the passenger compartment during and after the structure has been subjected to the prescribed rollover test. Rollover test on a bus section was completed according to the regulation. The coordinates of body section before and after rollover were measured, and it was checked that the structure still complied with the requirements of residual space. Direct measurement on a bus is difficult because of its large size. Thus photogrammetry by photographing and 3 dimensional digital modeling was introduced, and the coordinates of each point were measured through this method.

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Influence of Specimen Shapes on Tensile Behaviors of High Performance Fiber Reinforced Cement Composites (시험체 형상이 고인성시멘트복합체 인장거동에 미치는 영향)

  • Yang Il-Seung;Yun Hyun-Do;Han Byung-Chan;Shin Hong-Chul;Park Wan-Shin;Kim Sun-Woo
    • Proceedings of the Korea Concrete Institute Conference
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    • 2005.05b
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    • pp.65-68
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    • 2005
  • Social requirements to the civil and building structures have been changed in accordance with the social and economic progress. It is very important to develop the innovative structural materials and tecnology that the social requirements appropriately. Ductility of High Performance Fiber Reinforced cementitious Composites (HPFRCC), which exhibit strain hardening and multiple crackling characteristics under the uniaxial tensile stress are drastically improved. Because ductility in tensile test are very different according to specimen shapes, three types of the direct tensile test are performed. The tensile test are performed using the tensile test specimen, dummbell-shaped specimen, and cylinder specimen. As a result, tensile performance in HPFRCC is very good comparing to cylinder specimen because of direction characteristics of fibers. It is necessary to clarify the examination method of suiting to the usage.

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Environmental Fatigue Crack Propagation Behavior of Aged Cast Stainless Steel (열화 주조 스테인리스강의 환경피로균열 진전 거동)

  • Jeong, Ill-Seok;Lee, Yong-Sung;Kim, Sang-Jai;Song, Taek-Ho;Cho, Sun-Young
    • Proceedings of the KSME Conference
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    • 2004.04a
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    • pp.78-83
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    • 2004
  • Environmental fatigue crack propagation of CF8M and CF8A steels used in the domestic PWR were investigated on the simulated PWR condition(Temperature: $316^{\circ}C$, Pressure: 15MPa). The test equipment for environmental fatigue(high temperature-high pressure loop, autoclave, load frame, measurement system) were designed. As-received and 60-year aged specimens were used in the test. To compare with environmental fatigue test, another test was performed in the air condition. The fracture surface of specimens were difficult to verify the fracture modes such as striation, intergranular crack and cleavage and so on. As the ferrite content of CF8M is increased, more particles covered fracture surface were peeled.

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Inter-comparison Test of Lightning Impulse High Voltage Reference Measuring System (뇌충격 고전압 기준측정시스템의 국제비교시험)

  • Kim, Min-Kyu;Lee, Jeong-Gi;Choi, Ik-Soon;Jeong, Ju-Young;Kim, Ik-Soo
    • Proceedings of the KIEE Conference
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    • 2005.07c
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    • pp.2217-2219
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    • 2005
  • In this paper, an inter-comparison test of lightning impulse reference measurement system between Korea and Japan is reported. At present, such a direct comparison test as the activity to sustain the traceability of the measurement system is generally proposed. Due to the inter-comparison test, ascertaining the grade of the measurement uncertainty and maintaining the level of reference system are accomplished.

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A Comparative Study of the Detectable Methods of Residual Oxytetracyeline in Muscle of Flounder (Paralichthys olivaceus) with Simplified Screening Test (넙치 근육중 잔류 옥시테트라싸이클린의 간이스크리닝 검출방법 비교연구)

  • Jung, Sung-Hee;Kim, Jin-Woo
    • Journal of fish pathology
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    • v.11 no.1
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    • pp.77-81
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    • 1998
  • By standardized method, Bacillus subtilis BGA, Bacillus cereus var. mycoides ATCC 11778, and Micrococcus luteus ATCC 9341 were seeded on the muller hinton agar (Difco) plate, and pH was adjusted to 6.0, 7.2, and 8.0. Five agar plates, B. subtilis (pH 6.0), B. cereus (pH 6.0), B. subtilis (pH 7.2), B. subtilis (pH 8.0), and M. luteus (pH 8.0), were employed as test plates of modified EEC 4-plate method. Oxytetracycline (OTC) with a diet was orally administered to flounder, Paralichthys olivaceus, at 100 mg/kg once a day. After oral administration, modified EEC 4-plate method by the three screening test using muscle-direct, extraction-disk and direct-disk methods was conducted for 3 fish at 1, 3, 5, 10, 15, 20, 25 and 30 days. Muscle-direct treatment of B. subtilis (pH 6.0) was found to be dubious positive (${\pm}$) at the 1st day after the administration; thereafter, it was found to be negative to the last day of the experiment. Extraction-disk and direct-disk treatment of B. subtilis (pH 6.0) were found to be negative from the 1st day to the last day after the administration. B. subtilis (pH 7.2), B. subtilis (pH 8.0), and M. luteus (pH 8.0) by the three screening tests, were found to be negative all the way after the administration. On the other hand, B. cereus (pH 6.0) by the three screening tests was clearly found to be positive for the first 15 days after the administration, and then muscle-direct and direct-disk treatment of B. cereus (pH 6.0) were found to be dubious positive at 20th days after the administration. However extraction-disk treatment of B. cereus (pH 6.0) was clearly found to be negative at the same stage; thereafter, the three screening tests of B. cereus (pH 6.0) were found negative to the last of the experiment. These findings showed that to have equal sensitivity to those determination for the residual detection of OTC, and also confirmed that B. cereus was effective test organism for the monitoring of OTC.

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