• Nuclear Engineering and Technology
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• 제50권6호
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• pp.981-988
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• 2018

An experiment was performed for the OECD/NEA ROSA-2 Project with the large-scale test facility (LSTF), which simulated a steam generator tube rupture (SGTR) accident due to a double-ended guillotine break of one of steam generator (SG) U-tubes with operator recovery actions in a pressurized water reactor. The relief valve of broken SG opened three times after the start of intact SG secondary-side depressurization as the recovery action. Multi-dimensional phenomena specific to the SGTR accident appeared such as significant thermal stratification in a cold leg in broken loop especially during the operation of high-pressure injection (HPI) system. The RELAP5/MOD3.3 code overpredicted the broken SG secondary-side pressure after the start of the intact SG secondary-side depressurization, and failed to calculate the cold leg fluid temperature in broken loop. The combination of the number of the ruptured SG tubes and the HPI system operation difference was found to significantly affect the primary and SG secondary-side pressures through sensitivity analyses with the RELAP5 code.

• Nuclear Engineering and Technology
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• 제30권1호
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• pp.47-57
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• 1998

Boric acid concentrations of the refueling water storage tank and the accumulators for Westinghouse 3-loop type plants are increased to meet the post loss of coolant accident shutdown requirement for the extended fuel cycles from 12 months to 18 months. To maintain long term cooling capability following a LOCA, the switchover time is examined using BORON code to prevent the boron precipitation in the reactor core with the increased boron concentrations. The analysis results show that hot leg recirculation switchover times are shortened to 7.5 hours from 24 hours after the initiation of LOCA for Kori 3&4 and 8 hours from 18 hours for Ulchin 1&2, respectively. The How path in the mode J for Kori 3&4 is recommended to realign to the simultaneous recirculation of both hot and cold legs from the cold leg recirculation, as done by Ulchin 1&2.

• 한국의류학회지
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• 제23권5호
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• pp.667-671
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• 1999

The purpose of this study was to determine the number of skin cold receptor in Korean adult as a part of the study to investigate thermal physiological characteristics of Korean. For this 10 healthy subjects were placed in a climatic chamber and received cold stimulation of 1$0^{\circ}C$ on skin surface of each measuring site with a thermo-stimulator. As a result of cold spot measurement we found 23 points/cm2 at face 13. points/cm2 at chest 16 points/cm2 at abdomen 11 points/cm2 at back 14 points/cm2 at upper arm 16 points/cm2 at forearm 18 points/cm2 at back of the hand 15 points/cm2 at thigh 8 points/cm2 at leg 12 points/cm2 at dorsum of foot 8 points/cm2 at sole of foot in male subjects and in female subjects we fund 18 points/cm2 at face 13 points/cm2 at forearm 11 points/cm2 at at back of the hand 8 points/cm2 at palm 9 points/cm2 at thigh 6 points/cm2 at leg 8 points/cm2 at dorsum of foot 2 points/cm2 at sole of foot. The distributions of cold spots varied in different regions of the body surface and was exceptionally dense in the facial skin. There were some differences among other researchers' results but the cause of those differences are not yet known those are due to individual or methodological difference.

• 한국원자력학회:학술대회논문집
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• 한국원자력학회 2001년도 춘계학술발표회요약집
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• pp.256-256
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• 2001

• 제어로봇시스템학회:학술대회논문집
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• 제어로봇시스템학회 2003년도 ICCAS
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• pp.1244-1248
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• 2003

This paper describes visual tracking procedure of the underwater mobile robot for nuclear reactor vessel inspection, which is required to find the foreign objects such as loose parts. The yellowish underwater robot body tends to present a big contrast to boron solute cold water of nuclear reactor vessel, tinged with indigo by Cerenkov effect. In this paper, we have found and tracked the positions of underwater mobile robot using the two color information, yellow and indigo. The center coordinates extraction procedures are as follows. The first step is to segment the underwater robot body to cold water with indigo background. From the RGB color components of the entire monitoring image taken with the color CCD camera, we have selected the red color component. In the selected red image, we extracted the positions of the underwater mobile robot using the following process sequences; binarization, labelling, and centroid extraction techniques. In the experiment carried out at the Youngkwang unit 5 nuclear reactor vessel, we have tracked the center positions of the underwater robot submerged near the cold leg and the hot leg way, which is fathomed to 10m deep in depth.

• Asian-Australasian Journal of Animal Sciences
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• 제3권2호
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• pp.97-102
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• 1990

A procedure to standardize camel carcass fabrication is proposed. This includes a definitive method of jointing the carcass into wholesale neck, shoulder, brisket, rib, plate, loin, flank, rump and leg cuts. Carcass cutout data were collected from the right sides of 21 Najdi male camels averaging 8, 16 and 26 months of age in order to determine the influence of age on the weight of each wholesale cut. The weight of body, empty body, hot carcass, cold carcass, hump fat, kidney, pelvic and heart fat (KPH) and each wholesale cut increased (p < .01) with age. Except for percent shrinkage and wholesale rump weight, all studied traits increased (p < .01) linearly as the age increased. This change was most pronounced in wholesale flank and plate cuts, increasing by 4.2 and 3.4 times, respectively, while the rump and shoulder cuts changed the least, increasing by 1.8 and 1.9 times, respectively. Allometric growth coefficients indicated that as the camel grew, the weight of rib, brisket, plate and flank cuts increased relatively more rapidly than did cold carcass or empty body weight and that the weight of wholesale shoulder, neck, leg and rump increased less rapidly than did cold carcass or empty body weight.

• 대한전자공학회:학술대회논문집
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• 대한전자공학회 2003년도 하계종합학술대회 논문집 Ⅳ
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• pp.2259-2262
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• 2003

This paper describes visual tracking procedure of the underwater mobile robot for nuclear reactor vessel inspection, which is required to find the foreign objects such as loose parts. The yellowish underwater robot body tend to present a big contrast to boron solute cold water of nuclear reactor vessel, tinged with indigo by Cerenkov effect. In this paper, we have found and tracked the positions of underwater mobile robot using the two color informations, yellow and indigo. The center coordinates extraction procedures is as follows. The first step is to segment the underwater robot body to cold water with indigo background. From the RGB color components of the entire monitoring image taken with the color CCD camera, we have selected the red color component. In the selected red image, we extracted the positions of the underwater mobile robot using the following process sequences: binarization labelling, and centroid extraction techniques. In the experiment carried out at the Youngkwang unit 5 nuclear reactor vessel, we have tracked the center positions of the underwater robot submerged near the cold leg and the hot leg way, which is fathomed to 10m deep in depth.

• Nuclear Engineering and Technology
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• 제41권10호
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• pp.1263-1274
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• 2009

Several experimental tests to simulate a reflood phase of a cold-leg LBLOCA of the APR1400 have been performed using the ATLAS facility. This paper describes the related experimental results with respect to the thermal-hydraulic behavior in the core and the system-core interactions during the reflood phase of the cold-leg LBLOCA conditions. The present descriptions will be focused on the LB-CL-09, LB-CL-11, LB-CL-14, and LB-CL-15 tests performed using the ATLAS. The LB-CL-09 is an integral effect test with conservative boundary condition; the LB-CL-11 and -14 are integral effect tests with realistic boundary conditions, and the LB-CL-15 is a separated effect test. The objectives of these tests are to investigate the thermal-hydraulic behavior during an entire reflood phase and to provide reliable experimental data for validating the LBLOCA analysis methodology for the APR1400. The initial and boundary conditions were obtained by applying scaling ratios to the MARS simulation results for the LBLOCA scenario of the APR1400. The ECC water flow rate from the safety injection tanks and the decay heat were simulated from the start of the reflood phase. The simulated core power was controlled to be 1.2 times that of the ANS-73 decay heat curve for LB-CL-09 and 1.02 times that of the ANS-79 decay curve for LB-CL-11, -14, and -15. The simulated ECC water flow rate from the high pressure safety injection pump was 0.32 kg/s. The present experimental data showed that the cladding temperature behavior is closely related to the collapsed water level in the core and the downcomer.

• 설비공학논문집
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• 제29권12호
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• pp.654-662
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• 2017

When emergency core cooling system (ECCS) is operated during loss of coolant accident (LOCA) in a pressurized water reactor (PWR), pressurized thermal shock (PTS) phenomenon can occur as cooling water is injected into a cold leg, mixed with hot primary coolant, and then entrained into a reactor vessel. Insufficient flow mixing may cause temperature stratification and steam condensation. In addition, flow vibration may cause thermal stresses in surrounding structures. This will reduce the life of the reactor vessel. Due to the importance of PTS phenomenon, in this study, calculation was performed for Test 1 among six types of OECD/NEA ROSA tests with ANSYS CFX R.17. Predicted results were then compared to measured data. Additionally, because temperature difference between the hot coolant at the inlet of the cold leg and the cold cooling water at the inlet of the ECCS injection line is 200 K or more, buoyancy force due to density difference might have significant effect on thermal-hydraulic characteristics of flow. Therefore, in this study, the necessity to include buoyancy force term in governing equations for accurate prediction of single phase thermal stratification in both cold legs and downcomer by ECCS injection was numerically studied.

• 한국전문물리치료학회지
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• 제3권1호
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• pp.48-56
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• 1996

The research of cold therapy is preceding rarely nowadays. This study was researched to measure the skin temperature of the right foot malleolus when the leg change the situation precisely speaking it was cold, elevation, cold plus elevation. Twenty young healthy volunteers(M:10, F:10)with no history of cardiopulmonary disease, peripheral artery disease were tested. This study were analyzed by one-way-repeated ANOVA. In the first we examined the within changes of the skin temperature between before and after examination for each modality. The skin temperature at all of modalities had fallen. Therefore we could know the fact that elevation plus cold modality had fallen skin temperature significantly more than elevation or cold. And there were no significant difference between male and female. We conclude that elevation and cold therapy could be better effective on edema, contusion and sprain than cold or elevation therapy independently.