• 보존과학회지
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• 제5권2호
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• pp.15-24
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• 1996

Th)s study was carried out of the historical characters and textile coservations for Mrs. Danha Lee's Wonsam. As the textile material was silk, dry cleaning method was suggested. The solvents for dry cleaning were n-hexane, n-decane, and benzene. During the second cleaning process, the dry soap(HI-TECH, 120:1, volume ratio) was added to the mixed solvents. The reaction's temparature was $20^{\circ}C$, and the reaction's time was 30 minuutes. It seemed to be a gift for hot from the Royal Family because of the attachment of pheonlx hungbae. This wonsam was decorated symmetrically by gold weaving yarn, the basic fabric was green silk satin with glorius letters and floral patterns. It was made on the 17th C and the oldest thing among them.

• 한국표면공학회:학술대회논문집
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• 한국표면공학회 2015년도 추계학술대회 논문집
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• pp.242-243
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• 2015

Fault detection using optical emission spectra with modified K-means cluster analysis and principal component anal ysis are demonstrated for inductive coupl ed pl asma cl eaning processes. The optical emission spectra from optical emission spectroscopy (OES) are used for measurement. Furthermore, Principal component analysis and K-means cluster analysis algorithm is modified and applied to real-time detection and sensitivity enhancement for fluorocarbon cleaning processes. The proposed techniques show clear improvement of sensitivity and significant noise reduction when they are compared with single wavelength signals measured by OES. These techniques are expected to be applied to various plasma monitoring applications including fault detections as well as chamber cleaning endpoint detection.

• 제어로봇시스템학회논문지
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• 제22권6호
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• pp.470-476
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• 2016

This paper proposes a practical algorithm for the reduction of measurement errors due to drift in a micro-electromechanical system (MEMS) gyros that are used for a mobile robot. Any drift in a MEMS gyro will cause an unbounded growth of errors in the estimation of heading, which makes it nearly useless in applications that require high accuracy over a long operating time. In proposed method, maneuvers of a cleaning robot are observed through encoders' measurement process and a decision to correct bias drift will be made if necessary. The method used in this paper is called the "heading estimation filter". To evaluate the accuracy of the proposed method, a comparison was made between the estimation of the heading of the cleaning robot and one from a motion capture system.

• 대한가정학회지
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• 제34권3호
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• pp.75-87
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• 1996

The purpose of the study was to examine the effect of sex role orientation on the amount of time spent in meal preparation and cleanup, clothing care, and indoor cleaning accomplished by husbands and wives in couple-headed households in the U.S.. The overall research hypotheses examined were : (1) there is a relationship between demographic and socioeconomic characteristics of the husband and wife and the sex role orientation of the husband and wife; (2) for both husbands and wives, there is a relationship between sex role orientation and the amount of household production time that is accomplised by each individual; and (3) the relationship between sex role orientation and the amount of household production time remains when demographic and socioeconomic factors are controlled. The 1981 data from the 1975-1981 Time Use Longitudinal Panel Study collected at the University of Michigan were used for this study. The major findings is that a relationship between sex role orientation and the amount of time spent in three household production activities was not found, when all independent variables were controlled. That is, sex activities was not found, when all independent variables were controlled. That is, sex role orientation was not a predictor affecting the amount of time that husbands and wives spend on meal preparation and cleanup, clothing care, and indoor cleaning.

• 한국기계가공학회지
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• 제14권5호
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• pp.1-7
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• 2015

Cleaning by injecting dry ice and water is a generally adopted trend these days to clean molds (injection, diecasting foundry, press, rubber mold, etc). This cleaning method is performed manually, or by installing multiple high pressure spray nozzles. We have manufactured a turbine cleaning module device that is able to clean diecasting modules at any position and angle in the space by mounting an articulated robot instead of the existing pipe type injection nozzle, to minimize lead time and enhance working yield of the cleaning process. In this paper, we analyzed process factors that are required to design the turbine module by reviewing number of revolution, and results according to different blade angles and thicknesses of the mold release injection turbine module, using computational fiuid dynamics (CFD).

• 한국마이크로전자및패키징학회:학술대회논문집
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• 한국마이크로전자및패키징학회 2000년도 Proceedings of 5th International Joint Symposium on Microeletronics and Packaging
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• pp.57-64
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• 2000

As integrated circuits become more complex, the number of I/O connections per chip grow. Conventional wire-bonding, lead-frame mounting techniques are unable to keep up. The space saved by shrinking die size is lost when the die is packaged in a huge device with hundreds of leads. The solution is bumps; gold, conductive adhesive, but most importantly solder bumps. Virtually every semiconductor manufacturer in the world is using or planning to use bump technology fur their larger and more complex devices. Several wafer-bumping processes used in the manufacture of bumped wafer. Some of the more popular techniques are evaporative, stencil or screen printing, electroplating, electrodes nickel, solder jetting, stud bumping, decal transfer, punch and die, solder injection or extrusion, tacky dot process and ball placement. This paper will discuss the process steps for bumping wafers using these techniques. Critical cleaning is a requirement for each of these processes. Key contaminants that require removal are photoresist and flux residue. Removal of these contaminants requires wet processes, which will not attack, wafer metallization or passivation. research has focused on enhanced cleaning solutions that meet this critical cleaning requirement. Process parameters defining time, temperature, solvency and impingement energy required to solvate and remove residues from bumped wafers will be presented herein.

• 마이크로전자및패키징학회지
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• 제7권1호
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• pp.51-59
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• 2000

As integrated circuits become more complex, the number of I/O connections per chip grow. Conventional wire-bonding, lead-frame mounting techniques are unable to keep up. The space saved by shrinking die size is lost when the die is packaged in a huge device with hundreds of leads. The solution is bumps; gold, conductive adhesive, but most importantly solder bumps. Virtually every semiconductor manufacturer in the world is using or planning to use bump technology for their larger and more complex devices. Several wafer-bumping processes used in the manufacture of bumped wafer. Some of the more popular techniques are evaporative, stencil or screen printing, electroplating, electroless nickel, solder jetting, stud humping, decal transfer, punch and die, solder injection or extrusion, tacky dot process and ball placement. This paper will discuss the process steps for bumping wafers using these techniques. Critical cleaning is a requirement for each of these processes. Key contaminants that require removal are photoresist and flux residue. Removal of these contaminants requires wet processes, which will not attack, wafer metallization or passivation. Research has focused on enhanced cleaning solutions that meet this critical cleaning requirement. Process parameters defining time, temperature, solvency and impingement energy required to solvate and remove residues from bumped wafers will be presented herein.

• Journal of Welding and Joining
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• 제19권3호
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• pp.305-310
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• 2001

UBM-coated Si-wafer was fluxlessly soldered with glass substrate in $N_2$ atmosphere using plasma cleaning method. The bulk Sn-37wt.%Pb solder was rolled to the sheet of $100\mu\textrm{m}$ thickness in order to bond a solder disk by fluxless 1st reflow process. The oxide layer on the solder surface was analysed by AES(Auger Electron Spectroscopy). Through rolling, the oxide layer on the solder surface became thin, and it was possible to bond a solder disk on the Si-wafer with fluxless process in $N_2$ gas. The Si-wafer with a solder disk was plasma-cleaned in order to remove oxide layer formed during 1st reflow and soldered to glass by 2nd reflow process without flux in $N_2$ atmosphere. The thickness of oxide layer decreased with increasing plasma power and cleaning time. The optimum plasma cleaning condition for soldering was 500W 12min. The joint was sound and the thicknesses of intermetallic compounds were less than $1\mu\textrm{m}$.

• 국제학술발표논문집
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• The 9th International Conference on Construction Engineering and Project Management
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• pp.295-303
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• 2022

Residential heating systems in South Korea are largely based on the use of ondol pipelines. Heat is transferred to the floor by passing hot water through a metal or plastic pipe buried within the concrete of the floor. Consequently, it is difficult to clean the inside of these pipes after installation. Over time, foreign substances such as scale accumulate in the pipe when the ondol heating method is used for an extended period. Therefore, in the past, pipes were cleaned by removing foreign substances attached to the inside surfaces of the pipes using high-pressure water or by disassembling the pipes and removing foreign substances with chemical agents. Recently, a method for removing foreign substances through the cavitation effect of ultrasound has been proposed. This idea might lead to the development of new technologies for cleaning pipe interiors. Consequently, this study investigated the use of ultrasound to clean pipes embedded in concrete. In this study, devices that generated ultrasonic waves with various frequencies and directions were prepared. After preparing arbitrarily contaminated pipes, the appropriate frequency, output strength, and output direction for each foreign substance were determined through repeated experiments. The results of this experiment could provide important information for future methods of cleaning the interior of ondol piping systems.

• Nuclear Engineering and Technology
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• 제26권1호
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• pp.140-148
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• 1994

원전 증기발생기 2차측 제철 화학세정을 기존의 93$^{\circ}C$ 표준공정보다 고온인 1$25^{\circ}C$에서 검증시험을 수행하였다. 원전 증기발생기를 1$25^{\circ}C$에서 화학 세정한다는 가정아래 현장세정 조건을 결정하고 이를 다시 모사하여 3l 용량의 소형 검증시험 조건을 결정하였다. 1 gallon 용량의 316 스텐레스강 압력용기를 반응용기로 사용하는 화학세정 시험장치에서 검증시험을 수행하여 스러지 용해거동, 모재 부식률, 세정제 화학조성 변화거동 등을 측정하였다. 1$25^{\circ}C$ 검증시험 결과에서 93$^{\circ}C$ 표준공정보다 세정시간을 절반이하로 단축시키고도 더 효율적인 세정효과를 얻을 수 있을 뿐만이 아니라 2차측 모재의 부식률도 감소함을 확인할 수 있었다. 그러나 고온 세정공정은 아직 현장적용 경험이 없고, 별도의 외부순환 세정 장치를 이용하는 93$^{\circ}C$ 표준공정과는 달리 주냉각재의 잠열로 2차측을 가열하므로 세정이 완료될 때까지 주냉각 펌프를 계속 가동하여야 하는 단점이 있다. 가동중인 증기발생기에 대한 화학세정을 수행할 때 93$^{\circ}C$ 표준공정과 고온공정의 장 단점을 신중히 검토하여 최적공정을 적용하여야 할 것이다.