• International Journal of Ocean Engineering and Technology Speciallssue:Selected Papers
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• v.6 no.1
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• pp.75-81
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• 2003

Underwater wet arc welds were experimentally performed on the KR-RA steel plate as base metal by using four different types of flux coated electrodes: KT33, UWEE, UWCS, and TN20. UWEE, the individually designed flux coated underwater electrode, had good operability when compared with other domestic terrestrial electrodes, and imported goods. The hardness value and the portion of martensite of HAZ were increased, by using a rapid cooling rate, Mechanical properties were also examined experimentally with a multi-pass butt-welding specimen test. The individually designed flux coated electrode UWEE could be used in practice for underwater wet welds.

• Proceedings of the Korean Society of Marine Engineers Conference
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• 2001.05a
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• pp.180-186
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• 2001

Underwater wet welding process was experimentally investigated by using the six types of flux coated electrodes of 3.2mm diameter and the KR-RA steel plate of 11mm thickness as base metal. Two types of electrodes were domestic covered are welding electrode(CR13, CR14) and another two types of wet welding electrodes(UW-CS-01, TN-20) and the other two types(UW-X1, UW-X2) where individually designed flux coasted electrode for experimental welding purpose.

• Proceedings of the Korean Environmental Sciences Society Conference
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• 2005.11a
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• pp.167-170
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• 2005

충주댐 상${\cdot}$하류 하천 주요 지점의 수위-유량 상관관계를 분석하기 위하여 2004년 3월부터 12월까지 266일간 4개 수위국 지점을 대상으로 현지조사 및 하천측량을 실시하고, 홍수기 및 평${\cdot}$갈수기에 유량측정을 실시하여 수위-유량 관계식을 유도하였으며, 이를 바탕으로 유출량산정과 유황분석을 실시하였다. 평${\cdot}$갈수기 신뢰성 있는 수위-유량 관계곡선을 유도하기 위하여 실시간으로 관측되는 수위를 확인(www.wamis.go.kr)하여 측정지점의 수위를 균형있게 분포되도록 하여 신뢰도 향상을 기할 수 있었다. 2004년 홍수기, 평갈수기에 측정한 수위-유량성과를 이용하여 수위-유량관계식을 홍수기, 평갈수기로 나누어 유도하였으며, 표준편차와 상관계수를 검토한 결과 대체로 이차식 형과 지수식 형에 의한 계산치가 실측치에 근접하는 것으로 나타났다. 본 연구에서 작성한 수위-유랑관계식의 신뢰성 검증을 하기 위하여 2004년 7월 11일에서 7월 20일까지의 홍수시의 시간별 유출량자료와 2003년 11월 1일에서 2004년 10월 31일까지의 일별 유출량자료를 분석한 결과, 각 수위표지점의 첨두유량과 유출율 관계를 댐유입량 자료과 비교 검토하여 또한 HEC-RAS를 이용하여 수면형을 계산하여 수위-유량 관계식의 신뢰도가 높은 것을 확인할 수 있었다.

• Journal of Ocean Engineering and Technology
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• v.14 no.4
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• pp.56-61
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• 2000

This study has been performed for mechanical properties of underwater wet welding electrode with rolled steel (KR-RA) for ship structure, one kind (E 4313) of domestic covered arc welding electrode used in the air and two kinds (UWE-01, UWE-02) of underwater covered arc welding electrode experimentally developed on the same welding condition. The results obtained were as follows : The hardness value of underwater covered arc welding electrode (UWE-01) was about 8.3% lower than domestic covered arc welding electrode(E 4313) in heat affected zone of test of UWF-02 was lower about 4.5%. Tensile strengths of UWE-01 were about 0.9%, and those of UWE-02 were about 6.5% higher than those of domestic covered arc welding electrodes (E 4313) in test specimens. The impect value of UWE-01 were about 15.5%, and those of UWE-02 were about 21.7% highter than those of domestic covered arc welding electrodes(E 4313) in test specimens. So mechanical properties of the underwater arc welding electrode were improved by the composition ratios of covering materials.

• Corrosion Science and Technology
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• v.21 no.1
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• pp.68-76
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• 2022

Several technologies are employed to protect substrates from corrosion and erosion damage. In particular, arc thermal spray coating technology is widely used as anti-corrosive technology for steel and concrete structures and is applied to offshore plants and petrochemical and drilling facilities. In this investigation, solid particle impingement erosion experiments were performed on an arc thermal spraying-coated specimen using 85% Al-14% Zn-1% Zr wire rod in KR-RA steel. This study investigated the effect of fluorosilicone sealing on the erosion resistance characteristics of the thermal spray coating layer. The erosion rates of the thermal spray-coated and sealed specimens were 4.1×10^-4 and 8.5×10^-4, respectively. At the beginning of the experiment, the fluorosilicone sealant was almost destroyed by the impact of the solid particles. The destruction time for the coating layer was 10 minutes for the thermal spray-coated specimen and 13 minutes for the sealed specimens, indicating that the sealed specimens had better erosion resistance characteristics to solid particle impingement.

• The Korean Journal of Malacology
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• v.20 no.2
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• pp.165-169
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• 2004

The BLAST server for the mollusk was constructed on the basis of the Intel Server Platform SC-5250 dual Xeon 2.8 GHz cpu and Linux operating system. After establishing the operating system, we installed NCBI (National Center for Biotechnology Information) WebBLAST package after web server configuration for cgi (common gate interface) (http://chimp.kribb.re.kr/mollusks). To build up the stand alone blast, we conducted as follows: First, we downloaded the genome information (mitochondria genome information), DNA sequences, amino acid sequences related with mollusk available at NCBI. Second, it was translated into the multifasta format that was stored as database by using the formatdb program provided by NCBI. Finally, the cgi was used for the Stand Alone Blast server. In addition, we have added the vector, Escherichia coli, and repeat sequences into the server to confirm a potential contamination. Finally, primer3 program is also installed for the users to design the primer. The stand alone BLAST gave us several advantages: (1) we can get only the data that agree with the nucleotide sequence directly related with the mollusks when we are searching BLAST; (2) it will be very convenient to confirm contamination when we made the cDNA or genomic library from mollusks; (3) Compared to the current NSBI, we can quickly get the BLAST results on the mollusks sequence information.

• Journal of the Korean Society of Industry Convergence
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• v.7 no.3
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• pp.259-263
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• 2004

In the manufacture progress of LCD or semiconductor, there are used many kinds of gas like erosion gas, dilution gas, toxic gas as a progress which used these gas there are required high puritize to increase accumulation rate of semiconductor or LCD materials work progress of semiconductor or LCD it demand many things like the material which could minimize metallic dust that could be occured by reaction between gas and transfer pipe laying material, illumination of the surface, emition of the gas, metal liquation, welding etc also demand quality geting stricted. Material-Low-sulfur-contend (0.007-0010), vacuum-arc-remelt(VAR), seamless, high-purity tubing material is recommend for enhance welding lower surface defect density All wetted stainless steel surface must be 316LSS elecrto polishinged with ${\leq}0.254{\mu}m$($10.0{\mu}in$) Ra average surface finish, $Cr/Fe{\geq}1.1$ and $Cr_2O_3$ thickness ${\geq}25{\AA}$ From the AES analytical the oxide layer thickness (23.5~36 angstroms silicon dioxide equivalent) and chromum to iron ratios is similar to those generally found on electropolished stainless steel., molybdenum and silicon contaminants ; elements characteristic of stainless steel (iron, nickel and chromium); and oxygen were found on the surface Phosphorus and nitrogen are common contaminants from the electropolish and passivation steps.

• Journal of Society of Preventive Korean Medicine
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• v.18 no.3
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• pp.91-104
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• 2014

Objective : This study aims to compare the scope of practice of Korean Medicine doctors and western medicine doctors based on laws related to medical practice Method : We searched for laws related to medical practice using terminologies such as "Korean Medical practice", "Korean Medicine", "Principles of Korean Medicine", "western medicine", "Korean Medicine doctor", "western medicine doctor" at the national law information center(http://law.go.kr/main.html). Results : We categorized the laws we found into four categories: diagnosis, treatment, prescription, and all the other areas including public health. In diagnosis, both Korean Medicine doctors and western medicine doctors have a right to issue medical certificates including birth and death. However, diagnosis of a few specific diseases is allowed only to western medicine doctors. In treatment, laws related to emergency medicine and nursing at home were searched. Korean Medicine doctors and western medicine doctors are emergency care providers; however, most of emergency medicine can be done by western medicine doctors. In prescription, the scope of practice is divided by herbal medicine and western medicine. Finally, as public health professionals, both of them need to do lots of public health works. However, in some area such as vaccination, maternal and child health care, and industrial health, only western medicine doctors can practice. Conclusion : This study suggests that, in diagnosis, treatment, prescription, and all the other areas including public health, the scope of practice of Korean Medicine doctors and western medicine doctors has huge difference. There is also lack of consistency in current law, and some laws do not reflect current health care system and health care services.