• Journal of Environmental Science International
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• v.21 no.3
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• pp.383-390
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• 2012

For the cost-effective biological nitrogen removal (BNR) process whose characteristics of influent have low COD/N ratios, the automatic control system for the addition of external carbon based on oxidation-reduction potential (ORP) data in an anoxic reactor has been developed. In this study, it was carried out with a pilot-scale Bardenpho process which was consisted of anoxic 1, aerobic 1, aerobic 2, anoxic 2, aerobic 3 tank and clarifier. Firstly, the correlation coefficient ($R^2$) of the dosage of external carbon source and ORP value was about 0.97. Consequently, the automatic control system using ORP showed that the dosage of external carbon source was decreased by about 20% compared with a stable dosage of 75 mg/L based on the COD/N ratio of the anoxic influent.

• Journal of the Korean Society of Safety
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• v.11 no.3
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• pp.25-32
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• 1996

This study is a survey on the effect of working security and worksite environment connected to the worst case of noise and dust which was generated in the manufacturing workshop of machinery and easting. The noise intensity of the manufacturing process tends to increase up to the limited strength of 90db (A) or the higher during the last 4~5 years in 1990~1994. This result requires a significant improvement of worksite environment of unit workshop. The concentration of dust in the gouging process tends to increase to a significantly high level compared with other worksite, which also requires a local ventilation method to reduce the dust diffusion. Organic solvents used most frequently in the manufacturing process machinery were the aromatic hydrocarbons, but were gradually diversed in recent years.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 1997.11a
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• pp.185-188
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• 1997

The influence of slow cooling and annealing time in $O_2$ during melting and growth step in MPMG process on J$_{c}$ was investigated. Through the measurement of J$_{c}$ SEM and XRD, it can be observed that the critical characteristics were related with the slow cooling time and annealing time in 02 for melting and growth step of MPMG process. The distribution of critical current density with slow cooling time was the porabolic form and the value of J. was the highest at the 40 hour slow cooling time. And also, the value of J$_{c}$, along the annealing time in $O_2$ in the case of the slow cooling time 40 hour was inclined to increase with annealing time. Consequently, it can be suggested that proper slow cooling titre and annealing time along slow cooling in MPMG process be important to improve the critical characteristics.stics.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2004.05b
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• pp.72-77
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• 2004

The purpose of this study is to develop temperature measurement system with Rf sensors on shoes dry process. The experimental results showed that the developed system successfully could be applied on real dry process to reduce defective shoes caused from insufficient dry with scientific data management.

• Journal of Practical Engineering Education
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• v.6 no.2
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• pp.127-134
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• 2014

Analyzing test data of a vehicle for evaluating its emission performance is an essential process in automotive development field, yet it is intricate and tedious task. In addition, clear understanding and care are required when the analysis process is carried out. Computer software solutions significantly reduce the time and the effort for such analysis. Developing a computer routine to analyze the emission data in a vehicle test demands a complete understanding of the emissions analysis and its related details. In this paper, the principals to develop a LabVIEW analysis routine (VI) are introduced helping automotive engineers comprehend the emission analysis process of a vehicle test data and instruct them to develop similar routines for such analysis.

• 한국IT서비스학회:학술대회논문집
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• 2006.05a
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• pp.134-141
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• 2006

Today, the role of IT is so important that it is regarded as a partner of business, not a simple supporter. The more important the role of IT becomes, the higher the level of business needs rises and the more customers want. In the market of IT, more and more enterprises are establishing ITSM processes based on the ITIL for these environments: however they are experiencing the processes of trial and errors because of the shortage of references To improve these problems, in this study, we developed the ITSM model defined by investigation of the instance to which we have applied the ITIL Continuous Service Improvement Process which contains five phases such as High level Business Objectives. Assessment. Measurable Targets, Process Improvement, Measurement and Metrics. This model is an ITSM building framework to understand the concepts over the length and breadth of ITIL and minimize the trial and errors appearing during the building of the ITSM processes, and this paper presents a plan to develop the frameworks.

• Proceedings of the Korean Society for Technology of Plasticity Conference
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• 2008.05a
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• pp.142-145
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• 2008

Process simulation requires accurate and reliable data for a wide variety of material properties, ranging from thermal conductivity to flow stress curves. Traditionally such data are gathered from experimental sources, which has significant disadvantages in that not all of the required data is readily available, it may be from various sources that are themselves inconsistent, measurement of high temperature properties is expensive, and furthermore the properties can be sensitive to microstructure as well as to alloy composition. This article describes the development of a new multi-platform software program called JMatPro, which is based on CALPHAD methodology, for calculating the properties and behavior of multi-component alloys. A feature of the JMatPro is that the calculations are based on sound physical principles rather than purely statistical methods. Thus, many of the shortcomings of methods such as regression analysis can be overcome.

• Bulletin of the Korean Chemical Society
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• v.19 no.6
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• pp.676-680
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• 1998

The relaxation process of photogenerated carriers was investigated using conductivity measurement on ZnO under He, $H_2,\; CO_2\; and\; O_2$. The process was well explained with the rate constant of reaction or recombination of hole and electron, $k_h \;and\; k_e ( k_h > k_e)$, respectively. Generally, $k_h$ increased with the pressure of the gases. The slope of $k_h$ with respect to the pressure increased in the order of $H_2{\le}He, while $k_h$ of $O_2$ was sensitive to the history of the sample. The relaxation process on ZnO which was exposed to oxygen at 298 K and 573 K was observed during the illumination at 298 K and it was found that the rate constant of hole decreased with illumination time. From the result, it was suggested that the rate constant of photogenerated excess carriers was affected by the surface barrier of the semiconductor.

• Journal of the Korean Society of Manufacturing Process Engineers
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• v.18 no.9
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• pp.58-63
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• 2019

In this research, we examine the change of dimensional accuracy in the cutting process while changing cutting conditions such as feed rate and spindle rotational speed with chromium molybdenum steel (SCM415) material and TiCN- and TiAlN-coated end mill tools. According to dimensional accuracy measurement, TiCN-coated tool displays the most accurate dimensional tolerance at ${\varnothing}20mm$ at feed rates of 200 mm/min and 250 mm/min at a spindle rotation speed of 4,000 rpm. The largest dimension of the coating tool was able to make the TiAlN-coated tool suitable when comparing the smallest dimension.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.34 no.5
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• pp.333-336
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• 2021

Oxide YBCO bulk superconductors are manufactured using the melt process. Because seed crystal growth method utilizes a slow-spreading layer-by-layer reaction, a long-term heat treatment is required to manufacture a single-crystal specimen of several cm. In this study, the melt process method was applied to compensate for the shortcomings of the seed crystal growth method. The thickness of the upper and lower pellets of the YBCO bulk was molded to 40 mm, and YBCO superconductor was produced by heat treatment. The measurement results of capture magnetism was in line with the literature. This results in a relationship that the higher the growth of Y211 particle in the YBCO, the higher the superconducting properties. We analyzed the YBCO superconductor, focusing on the Y₂BaCuO₅ particle distribution.