Twin wire arc spray 공정을 통해 제작된 Al-Al2O3 복합소재미끄럼 방지 코팅의 우수한 마모 저항성

권한솔,박영진,강용진,남욱희,변응선,김도현 대한금속·재료학회 2024 대한금속·재료학회지 Vol.62 No.4

In this study, novel non-skid Al-Al2O3 coatings with improved wear resistance were fabricatedusing twin wire arc spray (TWAS). TWAS Al coating was prepared as a reference sample and representativeTWAS parameters (working distance, process gas pressure, arc current) were controlled to fabricate differentAl-Al2O3 coatings. The Al-Al2O3 coatings showed a superior static coefficient of friction and higher surfaceroughness than the Al coating. The microstructural analysis of the Al-Al2O3 coatings revealed that thecoatings contained Al splats, partially-melted Al2O3 particles, fully-melted Al2O3 splats and pores. The porosityand Al2O3 content of the Al-Al2O3 coatings varied with different process parameters. The Vickers hardnessof the Al matrix showed a similar value in all samples, which means the deposition phenomena was the same. Ball-on-disc wear test with a Si3N4 ball was used to evaluate the wear resistance of the TWAS coatings. Theweight loss of the Al-Al2O3 coatings were only 4.8 ~ 17.0 % of the Al coating, indicating that the wearresistance of the TWAS Al-Al2O3 coatings was superior. The TWAS coatings showed a complex wearmechanism, such as splat wear and abrasive wear. The distributed Al2O3 particles in Al-Al2O3 coatingsuccessfully suppressed the abrasive wear of the Al matrix, which contributed to the enhanced wearresistance. The results in this study indicated that the Al-Al2O3 composite coating has potential use as a novelnon-skid coating.

기억 속의 제일고녀, 구술 속의 식민지주의

권한솔 청람사학회 2023 靑藍史學 Vol.38 No.-

Twin wire arc spray 용사코팅 공정을 통해 제작된 내부식성 Al 및 Al-3%Ti 미끄럼 방지 코팅의 비교 연구

권한솔,박영진,남욱희,이은경,변응선 대한금속·재료학회 2023 대한금속·재료학회지 Vol.61 No.4

To ensure the lifetime of marine constructions and the safety of workers and pedestrians, corrosionprotective non-skid coating is an effective solution. However, the conventional polymer-based coating has somelimitations. In this study, newly-suggested Al and Al-3%Ti coatings were deposited on high strength lowalloyed steel substrate using twin wire arc spraying (TWAS). The static and dynamic friction coefficients ofthe Al-based coatings under dry and wet conditions were measured using portable friction testers. To evaluatethe corrosion behavior under sea water conditions, a cyclic potentiodynamic polarization test (CPDP) and saltsolution immersion test (SSIT) were performed with a 3.5% NaCl solution. To confirm the coating degradation,mechanical properties (Vickers hardness and adhesion strength) were compared before and after SSIT. Theresults showed that the TWAS Al-based coatings were well fabricated on HSLA steel and had the generalmicrostructure of a thermal spray. The coatings provided excellent corrosion protection for the steel substrateand greatly increased the friction coefficient of the surface. The Vickers hardness slightly increased andadhesion strength decreased after SSIT. The microstructure observation revealed that the TWAS coatings hada bimodal structure induced by non-uniform droplet generation at the TWAS tips. After SSIT, some oxidesformed on the surface and porous regions of the coatings. This indicated that the TWAS coating successfullyprovided corrosion protection and non-skid properties.

휴대용 DNA증폭기 MiniPCRTM mini8 Thermal Cycler의 성능 검토

권한솔,박현철,이경명,안상현,오유리,안으리,정주연,임시근 한국분석과학회 2016 분석과학 Vol.29 No.2

A small and inexpensive thermal cycler (PCR machine), known as the MiniPCRTM Mini8 Thermal Cycler (Amplyus, Cambridge, MA, USA), was developed. In this study, the performance of this PCR machine was compared with the GeneAmp® PCR system 9700 (Applied Biosystems) using four autosomal short tandem repeat (STR) kits, a Y-chromosome STR kit, and a mitochondrial DNA HV1/HV2 sequence analysis. The sensitivity and stochastic effects of the STR multiplex kits and the quality of the DNA sequence analysis were similar between the two PCR machines. The MiniPCRTM Mini8 Thermal Cycler could be used for analyses at forensic DNA laboratories and crime scenes. The cost of the PCR is so economical that school laboratories and individuals could use the machines.

Twin wire arc spray 용사코팅 공정을 통해 제작된 미끄럼 방지 코팅의 열적 특성 및 고온노출 거동 연구

권한솔,박영진,남욱희,변응선 대한금속·재료학회 2023 대한금속·재료학회지 Vol.61 No.9

Conventional non-skid coatings for marine construction contain polymeric materials. Thesematerials are generally susceptible to high temperature environments because of their low thermalconductivity and thermal resistance. A metal-based non-skid coating has great potential for hightemperature applications, yet, there has only been limited research. In this study, twin wire arc spray(TWAS) was used to fabricate Al and Al-3%Ti coatings on a high strength low alloyed (HSLA) steelsubstrate. The purpose of this study is to confirm the feasibility of TWAS Al-based coating for non-skidareas on marine construction. The static coefficient friction of TWAS Al-based coatings exhibited excellentand uniform values compared with a conventional epoxy-based non-skid coating. The specific heat andthermal conductivity of TWAS Al-based coating was measured and compared with that of the substrate. The thermal property values of the TWAS Al-based coating were reported for the first time in this study. The TWAS Al-based coating had A continuous interface with the substrate and the generalmicrostructural features of a thermal-sprayed metal coating. After exposure to 500oC for 24 hours, thean Fe-Al intermetallic compound and oxide were formed inside of the coating and coating-substrateinterface. The adhesion strength indicated that the TWAS Al-based coating sustained its strength afterthe isothermal exposure test. The Vickers hardness of the TWAS Al-3%Ti coating was higher than thatof the Al coating. The solid solution hardening of Ti atoms in the as-deposited coating and theprecipitation hardening of the TiAl3 compound in the heat-treated coating contributed to theimprovement of in Vickers hardness. Thus, the TWAS Al-3%Ti coating is proven to be a promising nonskidcoating for high temperature applications.

1920년대 조선인 실업학교 학생의 일상과 내면: 수학일지에 나타나는 근대교육과 규율을 향한 시선

권한솔 청람사학회 2022 靑藍史學 Vol.35 No.-

본 연구의 목적은 1920년대 중반 부산제2공립상업학교 학생이 작성한 『수학일지』를 소재로, 일기에 나타난 실업학교 학생의 일상과 내면을 분석하고 근대 학교교육이 학생의 삶에 미친 영향을 살펴보는 것이다. 『수학일지』는 조선인 학생 C군이 부산제2공립상업학교에 입학하여 약 2년간 작성한 2권의 일기다. 일기장에는 주임교원의 검사 흔적이 남아있는데, 근대 학교에서 이뤄진 일기 작성과 제출, 검사의 세 요소는 모두 교육의 일환이었다. 학업 상황 분석에 따르면, C군은 영어⋅수학 등 상업학교 학생에게 필요한 근대적 학과목을 적극적으로 소화하고 있었다. 시험성적은 學力의 증명이며 취업에 매우 중요했다. 『수학일지』에는 학교와 기숙사의 규율이 잘 드러난다. 특히 학교의 시간표와 기숙사의 ‘종’은 C군의 일과를 조밀한 간격으로 구획하였다. 이러한 학교규율에서 벗어나 자율이 확대되는 하계휴가 기간에는 자습 기록이 줄어들고, 기상시각은 현저히 늦어지는 모습을 보인다. C군은 ‘모범생’으로 존재하고자 했고, 우수한 학업성적을 위해 노력하거나 식민권력이 부여하는 규율을 내면화한 모습을 보인다. 『수학일지』는 식민지기에 쓰였기 때문에, 식민교육의 관점에서 ‘바람직한’ 서술들은 표면에 드러난다. 징후적으로는 C군이 조선인으로서 가진 자의식이 나타난다. ‘국어’ 대신 ‘일어’ 표현을 썼다가 교원에게 지적받는 행위 등은‘내면적 흔들림’이며, 1928년 동맹휴학 당시 퇴학당한 사실은 ‘흔들림’들이 극대화되어 나타난 ‘균열’이었다. 정리하면 근대 학교라는 규율권력의 공간에서 C군은 근대적 학과목과 규율, 그리고 식민주의 등을 수용하고 내면화하였다. 그러나 『수학일지』에 나타난 C군은 일률적인 모습뿐 아니라 자율성을 가지고 사고하며, 신념을 행동으로 옮기는 복합적인 면을 가지고 있었다.

사무용 건물의 자연채광 도입에 대한 국내ㆍ외 친환경 건축물 인증제도의 비교 분석 연구

권한솔(Kwon Han-Sol),김선욱(Kim Sun-Uk),엄현용(Eom Hyeon-Yong),정인영(Jung In-Yung),허정호(Huh Jung-Ho) 한국건축친환경설비학회 2008 한국건축친환경설비학회 학술발표대회 논문집 Vol.- No.-

The GBCC(Green Building Certification Criteria) system has been in effect since 2001, which has various assessment items according to the classification of building use. Nevertheless, the criteria related with daylighting has not been quantified yet as compared to the other indoor environmental factors in the GBCC, and even the established measure for interior lighting energy saving also have not existed. Therefore, this study is in progress as follows. First, the current state of day lighting-related items in the GBCC was examined. Second, the items were compared with the counterparts in the other foreign systems, such as LEED and CASBEE. Third, in the near future, this study plans to suggest the environmental-friendly certification criteria of daylighting utilization for office buildings.

업무용 건물 중앙공조 및 개별냉난방 시스템 연계운전방안

권한솔(Han-Sol Kwon),김용기(Yong-Ki Kim),이태원(Tae-Won Lee) 대한설비공학회 2013 대한설비공학회 학술발표대회논문집 Vol.2013 No.6

The daily electric energy consumption of the electrical heat pump(EHP) was investigated, and the heating coefficient of performance(COP) during winter season was analyzed in the present study. The optimal combination strategies of heating systems, which were composed of individual EHP’s and centralized gas boiler, were also determined in a medium sized domestic office building. It was found that the daily heating COP of EHP was lower than the given data by the producer especially in the region of relatively high outdoor air temperature. The optimal combination of operation strategies were proposed for the two types of heating systems installed in this testing building.

휴대용 DNA증폭기 MiniPCR<SUP>TM</SUP> mini8 Thermal Cycler의 성능 검토

권한솔(Han-Sol Kwon),박현철(Hyun-Chul Park),이경명(Kyungmyung Lee),안상현(Sanghyun An),오유리(Yu-Li Oh),안으리(Eu-Ree Ahn),정주연(Ju Yeon Jung),임시근(Si-Keun Lim) 한국분석과학회 2016 분석과학 Vol.29 No.2

건물 실시간 전력감시시스템(EPMS)을 이용한 건물 전력소비현황 분석 및 개선방안 도출

권한솔(Han-Sol Kwon),김용기(Yong-Ki Kim),이태원(Tae-Won Lee) 대한설비공학회 2013 대한설비공학회 학술발표대회논문집 Vol.2013 No.11

The shortage of electric power became an object of public concern in Korea, especially in summer and winter season. Many efforts and countermeasures have been considered to reduce electricity consumption, it was not easy to find out exact methods for managing electricity consumptions. The EPMS(Electric Power Monitoring System), a very useful tool for the easier and more convenient management of the electricity consumption in buildings, was developed. The several strategies with this tool were suggested in this paper to reduce the amount of consumptions and peak demand of the electric power consumption.