• Journal of Advanced Marine Engineering and Technology
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• v.33 no.4
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• pp.553-561
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• 2009

This paper presents development of ROV-type underwater robot capable of cleaning ship hull in automatic mode. The purpose of developing this robot is for underwater cleaning to secure the safety of divers who inspect and clean the ship hull. The robot consists of the cleaning system with rotating brush mechanism, a car-like driving mechanism, inspection system using video, and overall control system for underwater communication and operation. In this paper, we present overall design process of the cleaning system and operating system and technical contents of the overall control system for the underwater cleaning robot.

• The Journal of the Acoustical Society of Korea
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• v.16 no.1E
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• pp.49-56
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• 1997

Ultrasonic cleaning at high frequency around 1 MHz, called megasonic cleaning, is commonly used to remove particles less than 1 ㎛ by generating high frequency accelerations on the cleaning objects. Cleaning is performed in an ultrasonically-excited liquid contained in a double-structured container. Ultrasonic waves generated by piezoelectric transducers propagate in the outer container and are transmitted through the inner container. The bottom of the inner container is inclined to make oblique incidence of the ultrasonic wave in order to raise the efficiency of the transmission through the bottom plate. This work deals with the efficiency of the transmission, which directly affects the cleaning performance. The transmission characteristics of the ultrasonic wave in the megasonic cleaner have been obtained analytically and numerically for the variations of some parameters, such as the thickness and inclined angle of the bottom plate of the inner container and the chemical ratio and temperature of the cleaning liquid. The calculated results have yielded the optimum cleaning condition in terms of the sound power transmitted into the cleaning liquid.

• Proceedings of the KSME Conference
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• 2008.11a
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• pp.1880-1884
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• 2008

Cleaning is required following CMP (chemical mechanical planarization) to remove particles. The minimization of particle residue is required with each successive technology generation, and the cleaning of wafers becomes more complicated. In copper damascene process for interconnection structure, it utilizes 2-steop CMP consists of Cu CMP and barrier CMP. Such a 2-steps CMP process leaves a lot of abrasive particles on the wafer surface, cleaning is required to remove abrasive particles. In this study, the buffing is performed various conditions as a cleaning process. The buffing process combined mechanical cleaning by friction between a wafer and a buffing pad and chemical cleaning by buffing solution consists of tetramethyl ammonium hydroxide (TMAH)/benzotriazole(BTA).

• Journal of the Korean Applied Science and Technology
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• v.16 no.3
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• pp.237-240
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• 1999

This study showed that the optimized cleaning process using non-aqueous cleaning solvents is adaptable in the industrial field for existing 1.1.1-TCE cleaning solvents which is an ozone depleting sustance. Alternative cleaning solvent system substituted for existing cleaning solvent against non-aqueous pollutants(cutting & flux oil), was evaluated for the cleaning efficiency using gravimetric analysis method and surface change of sample by Image analyzer. The results showed that alternative solvents and process had excellent cleaning efficiency.

• Korean Membrane Journal
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• v.2 no.1
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• pp.60-63
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• 2000

The effect of Candida rugosa and steapsin lipase cleaning was investigated for ultrafiltration polyethersulphone membrane (30,000 dalton MWCO) fouled with the semi-synthetic type cutting oil. The experimental by the water circulator. The enzyme cleaning effect was measured with respect to temperature, cleaning time and enzyme concentration. The optimum cleaning condition for the system was 25$^{\circ}C$ and 2 hour cleaning with 1,000 unites/mL steapsin solution. The pure water flux improvement by the steapsin solution cleaning was about 17% at the optimum cleaning condition.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2017.05a
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• pp.272-273
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• 2017

As businesses put a greater emphasis on outward appearances, the demand for external window cleaning has been on the rise. However, with the conventional labor-intensive window cleaning method, it is hard to meet this demand. Therefore, this study proposes a Life Cycle Cost (LCC) analysis model for a guiderail-type cleaning robot, and estimate the LCCs of the conventional method and the cleaning robot. The findings of this research are expected to serve as a guide for future development of a cleaning robot.

• Membrane and Water Treatment
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• v.7 no.1
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• pp.1-10
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• 2016

Ultrafiltration is known to be one of the most commonly applied techniques in water treatment. Membrane fouling is the main limiting factor in terms of process efficiency and restricting it to the manageable degree is crucial. Natural organic matter is often found to be a major foulant in surface waters. Among many known fouling prevention techniques, the membrane chemical cleaning is widely employed. This study focuses on evaluating the cleaning efficiency of polymeric and ceramic membranes with the use of various chemicals. The influence of cleaning agent type and its concentration, membrane material and its MWCO, and cleaning process duration on the recovery of membrane flux was analyzed. Results have shown that, regardless of membrane type and MWCO, the most effective cleaning agent was NaOH.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2013.05a
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• pp.292-294
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• 2013

When the number of skyscrapers are increased in the domestic, it has increased the need of the outer wall cleaning robot. However, it does not exist the construction specification of the outer wall cleaning robot in the domestic. it is difficult to apply in the domestic that the outer wall cleaning robot. For this reason, it raised the need of the construction specification. And it is urgent that the construction specification of the outer wall cleaning robot is needed to develop in the domestic. Therefore, this study aims to propose the construction specification framework of the outer wall cleaning robot. In the future, this study will be based on the development of the construction specification on the outer wall cleaning robot.

• KEPCO Journal on Electric Power and Energy
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• v.7 no.1
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• pp.79-84
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• 2021

The fundamental element to be kept for big data analysis, artificial intelligence technologies and asset management system is a data quality, which could directly affect the entire system reliability. For this reason, the momentum of data cleaning works is recently increased and data cleaning methods have been investigating around the world. In the field of electric power, however, asset data cleaning methods have not been fully determined therefore, automatic cleaning algorithm of asset data for transmission cables has been studied in this paper. Cleaning algorithm is composed of missing data treatment and outlier data one. Rule-based and expert opinion based cleaning methods are converged and utilized for these dirty data.

• Clean Technology
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• v.17 no.2
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• pp.117-123
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• 2011

In this study, evaluation tests for cleaning performance of various cleaning agents and selection of optimal ultrasonic cleaning parameters were executed to develop an efficient cleaning process in remanufacturing of laser copy machine. Cleaning performance tests were executed with 8 cleaning agents (A~H) to remove the contaminants of oil-ink, toner particles, and shoe polish. Physical properties and foamability tests were also applied. For 3 types of contaminants, cleaning agent G showed superior cleaning performance compared to agent A which has being used at a remanufacturing of laser copy machine in Korea. With cleaning agents selected in pre-tests, ultrasonic cleaning tests were executed to remove real contaminants on the parts of used digital laser copy machine parts. Cleaning agent G at 28 kHz ultrasonic frequency showed faster cleaning performance compared to agent A and other frequencies. The productivity and economic efficiency in remanufacturing of laser copy machine are expected to increase by adapting agent G and 28 kHz frequency at ultrasonic cleaning process.