• 대한용접접합학회:학술대회논문집
• /
• 대한용접접합학회 2002년도 Proceedings of the International Welding/Joining Conference-Korea
• /
• pp.282-288
• /
• 2002

A new on-line bar joining technology employing the concept of a solid-state joining has been developed for the endless rolling by POSCO, RIST and MHMM Inc.. In the process, the bars are partially descaled, partially overlapped, joined by shearing action and crops are finally removed. The feasibility of the developed process was evaluated in this study in terms of microstructures and mechanical properties of joints, and the response of the joint to rolling.

• 펄프종이기술
• /
• 제36권1호
• /
• pp.75-80
• /
• 2004

This research was peformed to manufacture a shroud using hanji and to investigate the characteristics of the hanji shroud manufactured. A hanji shroud were manufactured by considering the designs of the traditional costumes of shroud. The vast fibers were used for the manufacture of hanji. The shroud manufactured could keep the natural feeling of hanji. The shroud showed the feasibility in sewing compared to textiles. However, fine needlework was required due to the poor appearance of small holes made by changing of sewing line. Since the hanji shroud has excellent ability in preservation for a long-term period and economical advantages compared to the shroud currently made by hemp and cotton cloth, the demand of the hanji shroud may be increased in the near future.

• 한국펄프종이공학회:학술대회논문집
• /
• 한국펄프종이공학회 2011년도 춘계학술발표회 논문집
• /
• pp.243-249
• /
• 2011

In the world, burning fossil fuels such as oil, petroleum, gasoline has created the global warming due to especially carbon dioxide gas emission. Therefore, these fossil fuels must be replaced by eco-friendly feadstocks. The wood pellets are one of valuable alternative fuels that can replace oil-based fuels within a short period of time. Unfortunately, there are no enough forest biomass for wood pellets in Korea. Nevertheless, Korea government has been trying to use most of forest biomass generated from the National Forest Management Operation. This does not make sense in an economic point of view.

• 한국전기전자재료학회논문지
• /
• 제28권3호
• /
• pp.196-200
• /
• 2015

In this paper, we fabricated flexible antenna radiator using the CNT/PVDF (carbon nanotube / polyvinylidene fluoride) composite film. We used polymer film as a matrix material for the flexible devices, and introduced CNTs for adding conductivity into the film resulting in obtaining performances of the antenna radiator. Spray coating method was used to form the CNT/PVDF composite radiator, and pattern formation of the radiator was done by shadow mask during the spray coating process. We investigated the electrical properties of the CNT/PVDF composite films with the CNT concentration, and also estimated the radiator performance. Finally we discuss the feasibility of the CNT/PVDF composite radiator for the flexible antenna.

• 전력전자학회:학술대회논문집
• /
• 전력전자학회 1998년도 Proceedings ICPE 98 1998 International Conference on Power Electronics
• /
• pp.341-345
• /
• 1998

This paper presents performance and loss analysis of Auxiliary Resonant Commutation Snubber-linked (ARCS) three phase voltage source soft switching inverter which is operated under a condition of Zero Voltage Switching (ZVS). The system performances of this ARCS soft switching inverter which is controlled on optimal type I digital servo scheme are illustrated and evaluated on the basis of experimental results.

• 대한전기학회:학술대회논문집
• /
• 대한전기학회 2006년도 제37회 하계학술대회 논문집 B
• /
• pp.787-790
• /
• 2006

This paper analyzes the principle and feature of the piezoelectric ceramic print head for the image printing of industrial inkjet plotter, and apply the Drop-on-Demand method that can adjust an ink drop size in accordance with the certain time adjustment. In order to do this study, drive frequency is selected at maximum 8.3[kHz] which can be operated within resonance frequency range of the piezoelectric ceramic. Drop controlling was realized according to pulse waveform the drive voltage, and grey-scale and satellite diminution method were applied for printing of high resolution image. A feasibility study of the result will be demonstrated by constructing the experiment equipment.

• 산업경영시스템학회지
• /
• 제30권3호
• /
• pp.1-11
• /
• 2007

The purpose of this study is to predict promising Location Based Services under an ubiquitous environment based on their technical characteristics, which is strongly required in rapidly changing circumstances with ubiquitous computing and Broadband Convergence Network (BcN). To begin with, this study proposes a classification scheme of ubiquitous services and defines five technology factors required for ubiquitous services. Next, this study collects a number of ubiquitous services from previous researches and classified them according to the classification scheme of ubiquitous services. And then, technical importance of the collected ubiquitous services are evaluated in terms of technology factors by using service-technology metrics. Finally, a set of important Location Based Services under ubiquitous environments and the correlations between technology factors are identified by using the evaluation results.

• 대한전기학회:학술대회논문집
• /
• 대한전기학회 2004년도 하계학술대회 논문집 B
• /
• pp.779-781
• /
• 2004

Recently, as the interests in the electrical propulsion ship increase, it is needed to prepare for the technical demand of the versatile HTS synchronous motor, the noble paradigm of the electrical motor. In this paper, the electrical propulsion apparatus was classified at first. The, the merits and demerits of the HTS synchronous motor were investigated. Finally, the feasibility study of development of the HTS motor was performed with electromagnetic FEM analysis. Additionally, the points to be considered in decision of the capacity or number of the HTS motor and the way to supply electricity were studied in this paper. This work would be very useful in establishing the development direction of the HTS motor

• 펄프종이기술
• /
• 제42권5호
• /
• pp.15-23
• /
• 2010

Bio-ethanol is the most potential next generation automotive fuel for reducing both consumption of crude oil and environmental pollution from renewable resources such as wood, forest residuals, agricultural leftovers and urban wastes. Lignocellulosic based materials can be broken down into individual sugars. Therefore, saccharification is one of the important steps for producing sugars, such as 6-C glucose, galactose, mannose and 5-C xylose, mannose and rhamnose. These sugars can be further broken down and fermented into ethanol. The main objective of this research is to study the feasibility and optimize saccharification and fermentation process for the conversion of lignocellulosic biomass to low cost bioethanol.

• 방사성폐기물학회지
• /
• 제19권2호
• /
• pp.255-266
• /
• 2021

Solid-state mechanochemical reduction combined with subsequent melting consolidation was suggested as a technical option for the oxide reduction in pyroprocessing. Ni ingot was produced from NiO as a starting material through this technique while Li metal was used as a reducing agent. To determine the technical feasibility of this approach for pyroprocessing, which handles spent nuclear fuels, thermodynamic calculations of the phase stabilities of various metal oxides of U and other fission elements were made when several alkaline and alkali-earth metals were used as reducing agents. This technique is expected to be beneficial, not only for oxide reduction but also for other unit processes involved in pyroprocessing.