• 상하수도학회지
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• 제34권6호
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• pp.445-462
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• 2020

Industrial wastewater often contains a number of recalcitrant organic contaminants. These contaminants are hardly degradable by biological wastewater treatment processes, which requires a more powerful treatment method based on chemical oxidation. Advanced oxidation technology (AOT) has been extensively studied for the treatment of nonbiodegradable organics in water and wastewater. Among different AOTs developed up to date, ozonation and the Fenton process are the representative technologies that widely used in the field. Based on the traditional ozonation and the Fenton process, several modified processes have been also developed to accelerate the production of reactive radicals. This article reviews the chemistry of ozonation and the Fenton process as well as the cases of application of these two AOTs to industrial wastewater treatment. In addition, research needs to improve the cost efficiency of ozonation and the Fenton process were discussed.

• 한국환경교육학회지:환경교육
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• 제20권4호
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• pp.1-11
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• 2007

The purpose of this study is to develope energy eco-audit evaluation scheme for the sustainable energy management at schools in accordance with education for sustainable development. Energy eco-audit evaluation scheme was developed through critical review of preexisting evaluation methods, consensus searching for the process from field. The results of this study are as follows. The school energy eco-audit evaluation scheme has three criteria: data collection, energy program, and environmental review. First, criteria of data collection includes general affairs, school building construction, and energy use. Second, criteria of energy program stresses school administration system such as the democratic decision-making process and structures. Third, criteria of environmental review includes reporting process and preparing teaching/learning materials for sustainable energy management. In conclusion, school energy eco-audit evaluation scheme could find a new way to achieve extended effect for sustainable energy management in school. It also could continue to seek opportunities to raise their awareness of energy issue and environment. School committee and whole school are involved to continue to implement present action plan and prepare updated plan in order to reduce environmental impact in school. By doing so, it would be possible to play important role in both school administration and education for sustainable development.

• 한국소성가공학회:학술대회논문집
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• 한국소성가공학회 2008년도 추계학술대회 논문집
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• pp.426-430
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• 2008

Hot shear-welding is a process of bonding two plates together by using shearing stress in a controlled manner. This study dealt with the hot shear-welding process of two aluminum plates. These two plates were piles up in the shear-welding mold. Due to the shearing stress, these two plates were cut off longitudinally, and meantime they were welded together. During this process the control of the surplus material flow is very important, and it can be realized by designing the overlapping length and the shape of the cavity. The commercial software Deform-3D was employed to predict the effect of these two factors. The overlapping length and the shape of the cavity that presents the optimum design was then developed to get a good shear-welding process.

• 한국재료학회지
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• 제26권8호
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• pp.438-443
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• 2016

We developed an Al sputtering process by varying the plasma power, process temperature, and film thickness. We observed an increase of hillock distribution and average diameter with increasing plasma power, process temperature, and film thickness. Since the roughness of a film increases with the increase of the distribution and average size of hillocks, the control of hillock formation is a key factor in the reduction of Al corrosion. We observed the lowest hillock formation at 30 W and $100^{\circ}C$. This growth characteristic of sputtered Al thin films will be useful for the reduction of Al corrosion in the future of the electronic packaging field.

• 한국해양공학회:학술대회논문집
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• 한국해양공학회 2000년도 춘계학술대회 논문집
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• pp.35-39
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• 2000

The piercing and blanking of thin sheet metal working is specified division in press die design and making. In order to prevent the detects, the optimum design of the production part, strip process layout, die design, die making and try out etc. are necessary the analysis of effective factors. For example, theory and practice of metal shearing process and its phenomena, die structure, machine tool working for die making, die materials and its heat treatment, metal working in industrial and its know how etc. In this study, we analyzed whole of data base, theoretical back ground of metal working process, and then performed the progressive die tryout with the screw press. This study regards to the aim of small quantity of production parts press working. Part 1 of this study reveals with production part and strip process layout design.

• Fibers and Polymers
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• 제2권1호
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• pp.140-143
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• 2001

To better understand the formation of necking in drawing processes of fibers, strain distributions during drawing processes have been analyzed. For simplicity, one-dimensional incompressible steady flow at a constant temperature was assumed and quasi-static model was used. To describe mechanical properties of solid polymers, non-linear visco-plastic material properties were assumed using the power law type hardening and rate-sensitive equation. The effects of various parameters on the neck formation were matematically analyzed. As material property parameters, strain-hardening parameter, visco-elastic coefficient and strain-rate sensitivity were considered and, for process parameters, the drawing ratio and the process length were considered. It was found that rate-insensitive materials do not reach a steady flow state and the rate-sensitivity plays a key role to have a steady flow. Also, the neck formation is mainly affected by material properties, especially for the quasi-static model. If the process length changes, the strain distribution was found to be proportionally re-distributed along the process line by the factor of the total length change.

• 한국기계가공학회지
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• 제13권2호
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• pp.15-20
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• 2014

The stereolithography(SL) process is a type of fabrication technology which relies on photopolymerization. It has a relatively simple fabrication process and a resolution of several tens of ${\mu}m$. Recently, SL technology has been applied to various areas, such as bioengineering and MEMS devices, due to the development of advanced materials. This technologycan be divided intothe scanning(SSL) and projection (PSL) types. In this paper, in stereolithography, parts are fabricated by curing photopolymeric resins with light. The application of stereolithography can now include fabricated parts. This process, called stereolithography, can fabricate parts by taking into account theirdegrees of geometry complexity. In particular, UV-LED stereolithography can perform quite rapid fabrication in which specific cross-sections are cured upon exposure to light.

• 한국멀티미디어학회논문지
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• 제20권9호
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• pp.1596-1605
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• 2017

This study recognizes the narrative of the movie as a semiotic system and proposes a structured storytelling analysis model through theoretical basis and empirical analysis. It classifies as 'Narrative 17 Process' which considers the narrative of successful 11 animations as a continuous process of formal structure. It extract the paradigmatic sub-narrative units(NU) centered on the act of the character in each process. The structural pattern of the story types are extracted by comparing and analyzing with 5 NU analysis elements presented in this study. As a result, the 4 story types were consistently classified by the SSD distance value. Therefore, this study propose a storytelling analysis model that can be effectively applied to scenarios and narrative composition stages of movie production.

• 한국주조공학회지
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• 제32권1호
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• pp.16-23
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• 2012

In this study, we develop the lower pressure die casting with rheo-forming process of A356 aluminum alloy and vacuum system which can control the crystal size and obtain the high strengthened-light material. Using this process, we fabricate the thin plate for bipolar plate through the low pressure die casting with electromagnetic stirring and vacuum-evacuation which can control the crystal grain by electromagnetic stirring. Thin plate ($110mm{\times}130mm{\times}1mm$) is fabricated by this process. The average Vickers hardness of thin plate is about 77 HV.

• 한국분말야금학회:학술대회논문집
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• 한국분말야금학회 2006년도 Extended Abstracts of 2006 POWDER METALLURGY World Congress Part2
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• pp.1292-1293
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• 2006

A non-equilibrium powder metallurgy processing such as an MA/SPS (Mechanical Alloying / Spark Plasma Sintering) process is examined in a Ti-48moll%Al. TiAl intermetallic compound is a potential light-weight/high-temperature structural material. One of the major problems, however, limiting the practical use of the material is its poor workability. From this point, the powder metallurgy (PM) processing route has been attractive alternative of the conventional processing for such material The MA/SPS process is able to apply to a LIGA process. Optimization of the pseudo-superplasticity enables to fabricate micro-parts made of fine grained ceramics composites of TiAl by the LIGA process.