• Korean Journal of Materials Research
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• v.11 no.5
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• pp.378-384
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• 2001

In this study, nanostructured Fe-Ce powder with grain size of 10nm was produced by MA (mechanical alloying) process and was consolidated by PECS (pulse electric current sintering) process for the fabrication of bulk nanostructured Fe-Co softmagnetic alloy. PECS process was performed at 700, 800, 900 and $^1000{\circ}C$ with holding time ranging from 0 to 15min. The effectiveness of PECS Process to Produce nanostructured bulk specimens was estimated. The optimal PECS process condition for nanostructured Fe-Co powders was found through observing the change of relative density and microstructure with sintering temperature and holding time. The magnetic properties of the sintered specimens were evaluated through the measurement of coercivity and saturation magnetization.

• Clean Technology
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• v.9 no.3
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• pp.107-113
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• 2003

Printing process generates a vast amount of toxical waste and wastewater by the development of printing and publishing industry. The regulations for various environmental pollution material, which were indispensably used in printing industries, were getting stronger. The printing industries should develop the cleaner technologies in order to avoid the regulations. In this paper, the separation characteristics of microfiltration, ultrafiltration, reverse osmosis were surveyed to make basic data for the optimization of process as cleaner technologies for printing industries. The $2kg/cm^2$ of operation pressure were suitable to the U/F System. Because of the permeate of U/F was below 3 NTU as turbidity, which was probed to be possible using the rinsing water in printing process. U/F System,

• Korean Chemical Engineering Research
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• v.59 no.4
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• pp.632-638
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• 2021

With the copper interconnection in the semiconductor process, complex residues including copper oxide, fluoride, and polymeric fluorocarbon are formed by plasma etching. In this study, a cleaning solution was prepared with a component having an amine group (-NH₂) and a carboxyl group (-COOH), and the characteristics of removing post-etch residues in the copper wiring process were analyzed. In the cleaning solution containing an amine group, the length of the component substituted with nitrogen and the length of the carbon chain influenced the cleaning effect, and the etching rate of copper oxide increased as the pH of the cleaning solution increased. The activity of the amine group is in the basic region, and the activity of the carboxyl group is in the acidic region, and the cleaning process proceeds through complex formation with copper or copper oxide in each region.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.25 no.1
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• pp.115-123
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• 2021

Manufacturing execution system is a factory information system that handles production-related quality data as well as executes production plans of process unit for all resources in the production process on site. As the 4th industrial revolution, which maximizes an automation and connectivity with artificial intelligence, has become a hot topic, manufacturers are showing interest in building a smart factories, but enormous construction costs and unstandardized production processes are obstacles to smart factory construction. Therefore, this paper designs and implements a manufacturing execution system for building a smart factory in a deterioration factory. we propose a Web-based manufacturing execution system aiming at a smart factory at the basic level for steel wire processing. The proposed system will smoothly support interworking with the existing ERP system using REST APIs, and will consider extensibility so that it can be used in various devices and browsers. We will show practicality by implementing the proposed WoT-based manufacturing execution system.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.26 no.7
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• pp.981-988
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• 2022

The intelligent production plant called smart factories that apply information and communication technology (ICT) are collecting data in real time through various sensors. Recently, researches that effectively applying to these collected data have gained a lot of attention. This paper proposes a method for the tool condition monitoring based on the sound signal generated in machining process. First, it not only detects a fault tool, but also presents various tool states according to idle and active operation. The second, it's to represent the power spectrum of the sounds as images and apply some transformations on them in order to reveal, expose, and emphasize the health patterns that are hidden inside them. Finally, the contrast-enhanced PSD image obtained is diagnosed by using CNN. The results of the experiments demonstrate the high discrimination potential afforded by the proposed sound PSD image + CNN and show high diagnostic results according to the tool status.

• Journal of IKEEE
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• v.27 no.3
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• pp.327-332
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• 2023

CNTFET, which is receiving high attention as a next-generation semiconductor candidate due to its higher performance and various utilization than traditional silicon-based semiconductor devices, is having difficulty in commercialization because its unique process deviation such as CNT placement has not yet matured. To overcome this difficulty, numerous studies have been continuously conducted to take advantages of CNTFET and compensate its weakness by implementing circuits, which are less affected by process deviation due to repetitive circuit placement, into MOSFET-CNTFET based hybrid circuits. This paper compares how much the performance of the hybrid SRAM can be changed by semiconductor process variation existing in the traditional MOSFET SRAM or CNTFET SRAM. Simulation results show that, if the CNT density can be maintained between 7 and 9 per 32nm, hybrid SRAM is about 2.6 times and about 1.1 times more robust to process deviation than conventional MOSFET SRAM in read and write operations, respectively.

• Journal of the Korea Institute of Building Construction
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• v.24 no.4
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• pp.495-506
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• 2024

Unlike reinforced concrete(RC) construction, the primary determinant of construction schedule for precast concrete(PC) apartment buildings is the lifting equipment. To establish a dry process-centric construction schedule, this study analyzes the lifting unit process for core, internal, and external PC wall components, which differ from traditional PC components. By examining the assembly process of these wall types, the study aims to determine the construction cycle for a standard floor frame of a PC apartment building. The findings will serve as foundational data for developing construction schedules for PC apartment buildings utilizing PC walls.

• The Journal of the Korea Contents Association
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• v.11 no.12
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• pp.658-673
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• 2011

This paper examined some problems of media coverage of religion by analyzing a television documentary. The SBS-TV documentary "God's way Man's way" aired in 2008, critically presented the basic Christian doctrine. The producers of the program estimate that protestant churches in Korea have become an established power, which has influence on a societal and political level. Therefore the producers believe that they have the right to criticize that power, especially because its doctrine about salvation leads to serious conflict with other religions, for example, Islam. This program portrayed the doctrine of Jesus as a story borrowed from ancient myths. Consequently, there were harsh protests from the Korean Christian milieu, especially protestants. The author agrees that it is important for the media to critically cover the activities of religious institutions and the behaviors of religious people in the civil society. However, if producers of a documentary want to introduce controversial doctrines of one religion to an audience, they should present the orthodox ones with alternatives or opposing ones, according to the principle of objectivity and fairness of journalism. Since every religion has its mysterious doctrine that cannot be proven by science and reason, journalists should not criticize the sacred part of religion. This paper suggested some ethical points to the media, children of Enlightenment Age, when they cover the religion including its doctrine and mysterious parts.

• Korean Journal of Construction Engineering and Management
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• v.16 no.6
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• pp.136-143
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• 2015

Snow-melting system has been applied not only to roads for car traffic but also to pavement for the pedestrians safety reason in some of the developed countries such as USA and Canada based on countermeasures against Natural Disasters Act revised in 2000. Even though this system was introduced in korea in 2006 and has been partly applied to car traffic roads, there is few places that the system has been applied. Therefore, in this research a snow-melting system with a block-type to cover a pavement that efficiently transfers heat form heat rays to the top of a pavement and protects the heat rays. A quality check showed that compression and bending strength was improved approximately 5 times stronger and 7 to 10 times more absorption rate than the KS(Korea Industrial Standard) requirement. Moreover, only 10 minute was required to increase temperature above zero with a block-type snow-melting system whereas approximately 180 minute was spent with the existing system. This research is expected to contribute to environmental issues and reduce accidents on a slippery road.

• Proceedings of the Korean Vacuum Society Conference
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• 2015.08a
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• pp.216.1-216.1
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• 2015

본 연구에서는 용액 공정 기반 AZTO (Aluminum-Zinc-Tin Oxide, AlZnSnO) 박막 트랜지스터를 제작하여 Al (Aluminum) 도핑과 열처리 온도의 가변을 통한 특성 향상을 확인하였다. ZTO 용액의 Zn:Sn 비율(4:7)을 고정하고 Al 도핑(0~8.3%)과 열처리 온도($350{\sim}550^{\circ}C$)를 가변하였다. 실험 결과 Al 도핑이 증가할수록 드레인 전류는 감소하고 문턱 전압이 양의 방향으로 이동하면서 포화 이동도와 아문턱 기울기가 감소하였다. 열처리 온도가 증가할 때는 드레인 전류가 증가하고 문턱 전압은 음의 방향으로 이동하며 이동도와 아문턱 기울기가 증가하였다. Al 도핑은 강한 금속-산소 결합에 의해 oxygen vacancy와 전자 농도가 감소하게 하여 드레인 전류, 이동도, 아문턱 기울기의 감소와 양의 방향 문턱 전압 이동을 야기한다. 열처리 온도가 높아지면 반도체 층의 분자 구조가 더 밀집되고 oxygen vacancy 가 증가하며, 이는 전자 농도의 증가로 이어져 Al 도핑의 효과와 반대의 경향을 보인다. 실험 결과를 통해 Al:Zn:Sn=0.5:4:7의 비율과 $350^{\circ}C$ 열처리 조건에서 문턱 전압과 이동도, 아문턱 기울기, 전류 온오프 비($I_{on}/I_{off}$)가 각각 3.54V, $0.16cm^2/Vs$, 0.43 V/dec, $8.1{\times}10^5$으로 우수한 특성을 확인하였다.