• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
• /
• 2005.11a
• /
• pp.354-355
• /
• 2005

Indium tin oxide (ITO) thin film was polished by chemical mechanical polishing (CMP) by the change of process parameters for the improvement of electrical and optical properties of ITO thin film. Light transparent efficiency of ITO thin film was improved after CMP process at the optimized process parameters compared to that before CMP process.

• Journal of the Korean Society of Industry Convergence
• /
• v.22 no.6
• /
• pp.785-795
• /
• 2019

This paper is a study on the modeling of the quantity estimation model for offshore plant Material handling equipment in FEED(Front End Engineering Design) verification stage using system engineering approach which is an engineering design methods. The relevant engineering execution procedure is not systemized although the operation method and Material handling equipment selection with weight and space constraints is a key part of the FEED. Using the system engineering process, the stakeholder requirements analysis process, the system requirements analysis, and the final system architecture design were sequentially performed, and the process developed through the functional development diagram and Requirement traceability matrix (RTM) was verified. In addition, based on the established process, we propose a Material handling quantity estimation model and Quantity calculation verification Table that can be applied at the FEED verification stage and we verify the applicability through case studies.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
• /
• v.27 no.8
• /
• pp.501-504
• /
• 2014

This paper was developed and described core-process to implement low on resistance which was the most important characteristics of SJ (super junction) MOSFET. Firstly, using process-simulation, SJ MOSFET optimal structure was set and developed its process flow chart by repeated simulation. Following process flow, gate level process was performed. And source and drain level process was similar to genral planar MOSFET, so the process was the same as the general planar MOSFET. And then to develop deep trench process which was main process of the whole process, after finishing photo mask process, we developed deep trench process. We expected that developed process was necessary to develop SJ MOSFET for automobile semiconductor.

• Journal of Powder Materials
• /
• v.21 no.5
• /
• pp.349-354
• /
• 2014

This study is a basic research for repair material production which manufactured a Cu repair coating layer on the base material of a Cu plate using kinetic spray process. Furthermore, the manufactured material underwent an annealing heat treatment, and the changes of microstructure and macroscopic properties in the Cu repair coating layer and base material were examined. The powder feedstocks were sphere-shaped pure Cu powders with an average size of $27.7{\mu}m$. The produced repair coating material featured $600{\mu}m$ thickness and 0.8% porosity, and it had an identical ${\alpha}$-Cu single phase as the early powder. The produced Cu repair coating material and base material displayed extremely high adhesion characteristics that produced a boundary difficult to identify. Composition analysis confirmed that the impurities in the base material and repair coating material had no significant differences. Microstructure observation after a $500^{\circ}C/1hr$. heat treatment (vacuum condition) identified recovery, recrystallization and grain growth in the repair coating material and featured a more homogeneous microstructure. The hardness difference (${\Delta}H_v$) between the repair coating material and base material significantly reduced from 87 to 34 after undergoing heat treatment.

• Journal of the Korean Society of Manufacturing Process Engineers
• /
• v.13 no.6
• /
• pp.54-60
• /
• 2014

In industry, several casting process are widely used to manufacture complex and accurate blank part of hard materials such as aluminum, casting steels, bronze and magnesium alloys which are difficult to manufacture in a blank shape. Even if the casting process does not high accuracy superior surface characteristics other machining process, the casting process is widely used in manufacturing blank part. Furthermore, it is difficult to select appropriate casting process a part among several casting process. for effective selection different process, a careful decision given casting application is necessary. An appropriate casting for a given material and shape condition must be selected for novice engineers in industry. In this paper, an expert system based on an analytic network process(ANP) is suggested for best selection of casting considering a prior interdependency effect among various factors such as material, geometry, process capability, economy and equipment.

• Journal of Power System Engineering
• /
• v.4 no.2
• /
• pp.40-45
• /
• 2000

Some engineering materials are often known to have considerable spatial variation in their resisting strength and other properties. The objective of this study is to investigate the averaging effect and the applicability of extremal statistic for the statistical size effect. In the present study, it is assumed that the material property is a stationary random process in space. The theoretical autocorrelation function of the material strength are discussed for several correlation lengths. And, in order to investigate the statistical size effect, the material properties was simulated by using the non-Gaussian random process method. The material properties were plotted on the Weibull probability papers. The main results are summarized as follows: The autocorrelation function of the material properties are almost independent of the averaging length. The variance decreases with increasing the averaging length. As correlation length is smaller, the slope is larger. And also, it was found that Weibull statistics based on the weakest-link model could not explain the spatial variation of material properties with respect to the size effect satisfactory.

• Journal of the Korean Society of Manufacturing Process Engineers
• /
• v.19 no.3
• /
• pp.29-35
• /
• 2020

This paper studies the main parameters of tube-to-bar dissimilar material and shape friction welding for piping materials. The weldability of joint parts was investigated with respect to tensile tests, micro-Vickers hardness, the bond of area, and optical microstructure. The specimens are tested as-welded. Optimal welding conditions are n = 2000 rpm, HP = 50 MPa, UP = 100 MPa, HT = 5 sec, and UT = 10 sec when the metal loss (Mo) is 11 mm. Moreover, the same two materials for friction welding are strongly mixed with a well-combined structure of micro-particles without any molten material, particle growth, or defects. Therefore, the expected result of dissimilar material friction welding includes a reduction of cost and material in the welding process.

• Journal of Nuclear Fuel Cycle and Waste Technology(JNFCWT)
• /
• v.20 no.1
• /
• pp.23-32
• /
• 2022

Pyroprocessing is a promising technology for managing spent nuclear fuel. The nuclear material accounting of feed material is a challenging issue in safeguarding pyroprocessing facilities. The input material in pyroprocessing is in a solid-state, unlike the solution state in an input accountability tank used in conventional wet-type reprocessing. To reduce the uncertainty of the input material accounting, a double-stage homogenization process is proposed in considering the process throughput, remote controllability, and remote maintenance of an engineering-scale pyroprocessing facility. This study tests two types of mixing equipment in the proposed double-stage homogenization process using surrogate materials. The expected heterogeneity and accounting uncertainty of Pu are calculated based on the surrogate test results. The heterogeneity of Pu was 0.584% obtained from Pressurized Water Reactor (PWR) spent fuel of 59 WGd/tU when the relative standard deviation of the mass ratio, tested from the surrogate powder, is 1%. The uncertainty of the Pu accounting can be lower than 1% when the uncertainty of the spent fuel mass charged into the first mixers is 2%, and the uncertainty of the first sampling mass is 5%.

• 제어로봇시스템학회:학술대회논문집
• /
• 2003.10a
• /
• pp.700-705
• /
• 2003

In this paper, an extended process model is proposed for the application of flexible belt grinding equipment as utilized in robotic grinding. The analytical and experimental results corresponding to grinding force, material removal rate (MRR) and contact area in the robotic grinding shows the difference between the conventional grinding and the flexible robotic grinding. The process model representing the relationship between the material removal and the normal force acting at the contact area has been applied to robotic programming and control. The application of the developed model in blade grinding demonstrates the effectiveness of proposed process model.

• Journal of Environmental Science International
• /
• v.8 no.2
• /
• pp.221-225
• /
• 1999

This study was conducted to evaluate the treatment efficiency including reaction kinetics and hydraulic characteristics of food processing wastewater by using an ejector-type aeration system (ETAS) in activated sludge process. The oxygen transfer efficiency in ETAS can be changed in accordance with the depth of reactor. However, the optimum air velocity was found less than 1.82 m/hr at a superficial liquid velocity of 634 m/hr. The ETAS process showed higher organic material removal efficiency than that of the existing activated sludge process under hydraulic detention time 6 to 12 hours. This process, which can maintain MLVSS highly, is able to have high organic material removal efficiency at short HRT and deal with variable organic material loading.