• Journal of the Korean Society for Precision Engineering
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• v.30 no.9
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• pp.977-982
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• 2013

Blades of wind energy plants are exposed to external shocks or internal cracks during operation. Furthermore, the blade surfaces can be contaminated by substances such as dust, blood of birds, salt or insects which can decrease the electricity generation efficiency significantly. For this reason, many blade cleaning companies started to appear and a variety of methods for cleaning were suggested. Despite these diverse methods, there has been no study to investigate how effectively to clean the substances in quantitative manner. In this paper, the cleaning efficiency of two rotor blade cleaning methods, brush and water-jet, is examined through experiments by changing operating parameters. Then, the optimal operating conditions for both methods are derived.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.35 no.5
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• pp.575-582
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• 2011

A cleaning blade is an attachment installed in the toner cartridge of a laser printer for removing the residual toner from an organic photo-conductive drum. There have been many studies on the performance and life of the rubber blade. We focus on optimally designing the blade shape parameters to minimize the maximum stress of the blade while satisfying design constraints on the cleaning performance and part interference. The blade is optimally designed using a design of experiments, meta-models and an optimization algorithm implemented in PIAnO (process integration, automation, and optimization), a commercial PIDO (process integration and design optimization) tool. We integrate the CAE tools necessary for the structural analysis of the cleaning blade, automate the analysis procedure, and optimize the solution using PIAnO. We decreased the maximum stress by 32.6% in comparison with that of the initial design.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2012.05a
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• pp.1041-1042
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• 2012

• Journal of Fisheries and Marine Sciences Education
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• v.26 no.1
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• pp.34-48
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• 2014

Marine algal assemblages on the artificial reefs at three stations (Haengwon, Geumneung, Pyoseon in Jeju-do) and the growth pattern of Ecklonia cava with water depth were studied before and after rocky cleaning. Nine algal species occurred at three artificial reefs before rocky cleaning in July 2012, however, 19 algal species were found at three artificial reefs after rocky cleaning in July 2013. In particular, 13 of 19 species in 2013 were replaced by different species which were not found in July 2012. Algal biomass rapidly increased in July 2013 after rocky cleaning. The nMDS plot based on the presence and absence data of macro-algal assemblages on the artificial reefs showed that the species compositions between artificial reefs were similar to each other before rocky cleaning operations in July of 2012. However, after rocky cleaning, the species composition of macro-algal assemblages in Haengwon region was similar to that in Pyoseon region while that in Geumneung region was different to those in Haengwon and Pyseon regions in July 2013. It is needed to clarify the suitable water depth for transplantation of perennial Phaeophyta E. cava. According to the data on seasonal changes in total length, total weight, blade length, blade width, blade weight of E. cava, it began to grow rapidly from April and reached to the maximum value in June, and then degeneration of the blade occurred in July and continued to early August. Although the total length of E. cava at 10m water depth was larger than those at 5 m and 15 m water depths, there was no significant difference statistically among water depths by ANOVA test. However, in the values of total weight, blade length, blade width, and blade weight, the growth patterns at 5 m water depth were larger than those at 10 m and 15 m. Thus, it is assumed that the most suitable water depth for transplantation and its maximum growth and effective release of zoospores of E. cava will be 7~10 m water depth.

• Proceedings of the Korean Reliability Society Conference
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• 2011.06a
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• pp.107-113
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• 2011

The windshield wiper consists of 4 parts: a blade, an arm, a linkage and a motor. The wiper blade makes contact with the windshield and is designed to be operated normally at an angle of 30~50 degrees to the front glass. If the contact pressure between the wiper blade and windshield surface is too high, noise and wear of the rubber will result. On the other hand, if the contact pressure is too low, the performance will do badly, since foreign substances such as dust and stains will not be removed well. The pressure and friction of the wiper blade has a great influence on its effectiveness in cleaning the front window. This is due to the contact of the rubber with the window. This paper presents the dynamic analysis method to estimate the performance of the flat type blade of the wiper system. The blade has a nonlinear characteristic since the rubber is an incompressible hyper-elastic and visco-elastic material. Thus, Structural dynamic analysis using a complex contact model for the blade is performed to find the characteristics of the blade. The flexible multi-body dynamic model is verified by the comparison between test and analysis result. Also, the optimization using the central composite design table is performed.

• Transactions of the Korean Society of Automotive Engineers
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• v.18 no.2
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• pp.83-90
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• 2010

The windshield wiper consists of 4 parts: a blade, an arm, a linkage and a motor. The wiper blade makes contact with the windshield and is designed to be operated normally at an angle of 30~50 degrees to the front glass. If the contact pressure between the wiper blade and windshield surface is too high, noise and wear of the rubber will result. On the other hand, if the contact pressure is too low, the performance will do badly, since foreign substances such as dust and stains will not be removed well. The pressure and friction of the wiper blade has a great influence on its effectiveness in cleaning the front window. This is due to the contact of the rubber with the window. This paper presents the dynamic analysis method to estimate the performance of the flat type blade of the wiper system. The blade has a nonlinear characteristic since the rubber is an incompressible hyper-elastic and visco-elastic material. Thus, Structural dynamic analysis using a complex contact model for the blade is performed to find the characteristics of the blade. The flexible multi-body dynamic model is verified by the comparison between test and analysis result. Also, the optimization using the central composite design table is performed.

• Journal of the Korean Society of Manufacturing Process Engineers
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• v.14 no.5
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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).

• Journal of the Korean Geosynthetics Society
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• v.23 no.2
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• pp.63-75
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• 2024

Drinking water is an essential element to ensure the basic human right to live, and the quality of clean water must always be ensured. However, domestic water facilities, which were installed intensively in the early 2000s, are deteriorating. The accidents such as discoloration of water such as chromaticity and turbidity as well as leakage of substances frequently occur. However, since it is virtually impossible to replace all water pipes, the detailed standards for maintenance of water pipe network facilities established in 2021 require water pipe cleaning. The swab pig method, one of the water pipe cleaning methods, is a method of physically removing substances in pipes and is evaluated as having the highest cleaning efficiency. However, Swab is highly likely to be damaged or deformed during the cleaning process, and may even be lost. Therefore, in this study, the material of the pig was changed to a material with high compressibility, and it was made as close as possible to the inner wall of the water pipe. And, to maximize cleaning efficiency, a rotation swab pig with a rotation blade was developed. In addition, high-strength wire and winding equipment were additionally developed to eliminate the possibility of loss and to determine the location of the pig. The inlet and outlet are connected with wires, and after verifying the performance of each detailed technology, the technology was applied on a test bed with a 30m section. As a result of the application, the performance of the technology was verified by measuring the process time and evaluating applicability.

• Transactions of the Korean Society of Mechanical Engineers B
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• v.20 no.5
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• pp.1639-1648
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• 1996

Protection of gas turbine blade from its erosion and abrasion at high temperature and pressure is the first goal to cleanup the hot gas upstream for IGCC and PFBC. Ceramic filters represent an attractive technology for particle removal at high temperature and high pressure condition. They have demonstrated being a good system for improvement of thermal efficiency and reduction of effluent pollutants in advanced coal-based power systems such as IGCC and PFBC. Ceramic filter elements currently being developed were evaluated in the previous paper. In this paper, we measured the ash size and distribution on cleaning of ceramic candle filter. The results are as follows : in this experimental range, ceramic candle filter was shown to be fully adequate for the removal process of dust under high temperature and pressure. Also filtration efficiency of ceramic candle filter was higher than 98% compared with the regulation limit of particle size in gas turbine inlet.

• Journal of the Korean institute of surface engineering
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• v.33 no.2
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• pp.101-106
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• 2000

SOI (Silicon-On-Insulator) substrates were fabricated with varying annealing temperature of $25-660^{\circ}C$ by a linear annealing method, which was modified RTA process using a linear shape heat source. The annealing method was applied to Si ∥ $SiO_2$/Si pair pre-contacted at room temperature after wet cleaning process. The bonding strength of SOI substrates was measured by two methods of Razor-blade crack opening and direct tensile test. The fractured surfaces after direct tensile test were also investigated by the optical microscope as well as $\alpha$-STEP gauge. The interface bonding energy was 1140mJ/m$^2$ at the annealing temperature of $430^{\circ}C$. The fracture strength was about 21MPa at the temperature of $430^{\circ}C$. These mechanical properties were not reported with the conventional furnace annealing or rapid thermal annealing method at the temperature below $500^{\circ}C$. Our results imply that the bonded wafer pair could endure CMP (Chemo-Mechanical Polishing) or Lapping process without debonding, fracture or dopant redistribution.