• Journal of Advanced Marine Engineering and Technology
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• v.39 no.1
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• pp.99-104
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• 2015

Life rafts, which has been used for domestic vessel currently, are fabricated mostly for the ocean-going vessels in accordance with the SOLAS Resolution. Therefore, there is not any small-sized life raft which can be installed on small fishery boat, leisure boat and cargo vessel with those length shorter than 20 meters in our country. However, in many foreign countries, new standards or the small-sized life rafts applicable to those small vessel have been developed according to the standard of ISO 9650. Furthermore, they make their effort to contribute the safety for the life at sea by supply the superior product of life rafts, which have been adopted by light material (i.e. thermoplastic polyurethane, TPU) and economic production process (i.e. heat sealing, radio-frequency welding, RFW), etc. In this paper, the development results of the small-sized life raft, which has been used the lightening material TPU and fabricated by RF-welding method, will be introduced.

• Proceedings of the Korean Society of Plant Biotechnology Conference
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• 2003.04a
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• pp.112-112
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• 2003

• 한국가스학회:학술대회논문집
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• 2003.10a
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• pp.77-84
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• 2003

• Journal of the Korean Vacuum Society
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• v.11 no.2
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• pp.81-86
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• 2002

With a specific model for the Helicoflex type metal gasket expected to be used in large ports of the KSTAR vacuum vessel, a sealing curve was obtained by measuring the flange tightening properties such as the correlations of the tightening torque(or linear load), displacement to the leak rate. From the experiment results it was found that the leak rate of the Helicoflex seal in the room temperature was bellow $2\times10^{-1}\textrm{mbar\cdot L/s}$ with a tightening torque of 2500kgf . cm using Ml8 bolts.

• 한국가스학회:학술대회논문집
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• no.5
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• pp.119-128
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• 2002

• Journal of computational fluids engineering
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• v.13 no.3
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• pp.21-27
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• 2008

The reactor head of a sodium-cooled fast reactor KALIMER-600 should be cooled during the reactor operation in order to maintain the integrity of sealing material and to prevent a creep fatigue. Analyzing turbulent natural convection flow in the cover gas region of reactor vessel with the commercial CFD code CFX10.0, the cooling requirement for the reactor head and the performance of the insulation plate were assessed. The results showed that the high temperature region around reactor vessel was caused by the convective heat transfer of Helium gas flow ascending the gap between the insulation plate and the reactor vessel inner wall. The insulation plate was shown to sufficiently block the radiative heat transfer from pool surface to reactor head to a satisfactory degree. More than $32.5m^3$/sec of cooling air flow rate was predicted to maintain the required temperature of reactor head.

• Journal of Veterinary Clinics
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• v.31 no.2
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• pp.149-151
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• 2014

A 170 kg, 9-year-old, female Asian black bear was presented for sterilization. Physical examination revealed no evidence of any abnormal clinical sign. Laparoscopic salpingectomy was performed for sterilization. A $25^{\circ}$ laparoscope was inserted in the first port, 1-cm caudal to the umbilical scar, to view the abdominal cavity. Two more ports were made 15 cm caudo-lateral to the first port bilaterally. An atraumatic grasper and a vessel-sealing device were inserted in the bilateral ports. The vessel-sealing device was used to seal and cut the fallopian tube and mesosalpinx. There was no sign of hemorrhage on the severed ends of the fallopian tube and mesosalpinx. At 4 weeks, no physical, behavioral, or other assessable impairment was found. This is the first case report in an Asian black bear to describe laparoscopic salpingectomy for sterilization.

• Journal of the Korean Institute of Gas
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• v.8 no.4 s.25
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• pp.30-35
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• 2004

In this paper, the metal seal for a pressure vessel has been analyzed using the Daguchi method. This method may efficiently optimize the design parameters for a cantilever sealing device of a pressure vessel in terms of dimensions and angles. The computed results indicate that the optimized design parameters can only be drawn by sixteen experimental numbers of iterations when the Daguchi design technique has been employed. This means that the Daguchi design method is very useful for the optimization design of the curved design of the structure. Based on the computed results by the Daguchi design technique, the dimension and angle of the metal seal structure are given as $d_1=50mm,\;d_2=60mm,\;a_1=20^{\circ},\;a_2=8^{\circ},\;a_3=5^{\circ}$.

• Transactions of the Korean Society of Pressure Vessels and Piping
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• v.16 no.1
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• pp.84-91
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• 2020

The APR1400 reactor stud holes can be stuck due to high temperatures, high pressure, prolonged engagement, and load changes according to pressure changes in the reactor. Threaded surfaces of a stud hole should be cleaned for the sealing of pressure in reactor vessel by removing any foreign materials which may exist in the stud holes. Human workers can access to the stud hole for the cleaning of stud holes manually, but the radiation exposure of human workers is increased. Robot is an effective way to work in hazardous area. So we introduced robot for the cleaning of stud holes. Localization of mobile robots is generally based on odometry, but with increased mileage, position errors can be accumulated. In order to eliminate cumulative error and to ensure stability of its driving, laser sensors and new control algorithm were utilized. The distance between the robot and the wall was measured by laser sensors, and the control algorithm was implemented so as to travel the desired trajectory by using the measured values from sensors. The performance of driving and hole sensing were verified through field application, and mobile robot was confirmed to be applicable to the APR 1400 NPP.

• Journal of the Korean Society for Precision Engineering
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• v.26 no.1
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• pp.97-104
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• 2009

There is a many kinds with nondestructive testing such as RT and UT representatively. Referred before two testing methods there is a limit which is spatial such as nuclear pipe, small vessel, sealing up vessel. So a new technique needs to overcome the limit which is spatial. shearography will be able to overcome the limit which is spatial. This paper introducing shearography which was known as non-contact full-field testing method and It is an interferometric technique for measurement of surface deformation such as displacement or displacement gradient. Also, a research about internal defect of the flange welding zone was accomplished. About variation with method pressurized with the Gaseous Nitrogen. Phase map where is various were measured according to changing a sheared direction, size of crack and loaded pressure. Consequently, crack quantitatively to be detected qualitatively was measured by using shearography.