• Korean Journal of Materials Research
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• v.10 no.10
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• pp.715-720
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• 2000

By the mechanical alloying method. Ni-WC composite materials were prepared to improve the deformation-resistance for creep and sintering of Ni-anode at the operating temperature of $650^{\circ}C$. Mechanically alloyed powder w was initially fabricated by ball milling for 80hr, and then amorphization was occurred by the destruction of ordered crystals based on XRD analysis. In order to investigate the electrochemical performance and sheet characteristics of Ni-WC anode, tape casting process was adopted. Finally, the obtained sheet thickness of Ni- we after sintering at $1180^{\circ}C$ for 60 minutes in $H_2$ atmosphere was O.9mm and the average pore size was $3~5{\mu\textrm{m}}$ with porosities of 55%. The second phase was not observed in Ni- W matrix while W particles were finely and uniformly distributed in Ni matrix. This fine and uniform distributed W particles in Ni matrix are expected to enhance the mechanical properties of Ni anode through the dispersion and solid solution hardening mechanisms.

• Korean Journal of Metals and Materials
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• v.56 no.11
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• pp.835-843
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• 2018

In this work, we report a delta rosette strain sensor based on highly stretchable silver nanowire (AgNW) percolation piezoresistors. The proposed rosette strain sensors were easily prepared by a facile two-step fabrication route. First, three identical AgNW piezoresistive electrodes were patterned in a simple and precise manner on a donor film using a solution-processed drop-coating of the AgNWs in conjunction with a tape-type shadow mask. The patterned AgNW electrodes were then entirely transferred to an elastomeric substrate while embedding them in the polymer matrix. The fabricated stretchable AgNW piezoresistors could be operated at up to 20% strain without electrical or mechanical failure, showing a maximum gauge factor as high as 5.3, low hysteresis, and high linearity ($r^2{\approx}0.996$). Moreover, the sensor responses were also found to be highly stable and reversible even under repeated strain loading/unloading for up to 1000 cycles at a maximum tensile strain of 20%, mainly due to the mechanical stability of the AgNW/elastomer composites. In addition, both the magnitude and direction of the principal strain could be precisely characterized by configuring three identical AgNW piezoresistors in a delta rosette form, representing the potential for employing the devices as a multidimensional strain sensor in various practical applications.

• Journal of Korean Home Economics Education Association
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• v.1 no.1
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• pp.1-17
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• 1989

Present, we cannot expect the maximum studying effect in a home economics and the drill unit of secondary schools because of several problems. Such problems can be enumerated as follows. 1. The explaination of a making process in texts would be difficult for the students who have a poor understanding to grasp. 2. The much effort would be made due to teacher’s repeated exhibition, by which the progress of a text might be unreasonable. 3. The teachers unaccustomed to the drill might treat it carelessly and become to avoid it. 4. The skill to grasp a general work flow might be lack. Baseing on such problems, this researcher did using a medium of Video in teaching method of home economics. For this purpose, the quality of Video Tape would be important. Above all, we made out the script of Video Tape through advices of specialists in Video medium, majors in home economics, and the students teaching of home economics and the concerned persons, by which we recorded a gather skirt, as a finished goods, especially of the characteristics of each kind of a skirt. Next, we recorded and produced the total steps from a preparation of skirt-making to a finishing as using a V.T.R. shot technique. The Video would be screened and the supplemented explaination of a teacher would be added in a step of instruction. In the development of instruction, students would begin the making. The expected effects according to using Video Tape are as follows. 1. The making order of text would be exhibited by a model directly and the explaination of a narrator would be added concurrently, by which students would understand it easily as confirming each step. 2. All students can watch these steps owing to a close up, one of the V.T.R Techniques. Accordingly, the teacher’s efforts would be decreased and the proper progress of a text could be maintained because of no repeated exhibition of a teacher. 3. To the teachers unaccustomed to and interested in a drill, the medium would become a subsidiary means. 4. Study all steps of a making, students would become to understand the general flow of a work. Therefore, it might be possible to generalize another units of a making. However though this study was designed don a basis of such effects, the using effects based on only the existing study results, and was focused on the production of a medium. Because this research would be a teacher and there was noncooperation of secondary schools, it was impossible to experiment in schools, which was the prime limitation of this study. Therefore we should be experiment further for the continuous studying.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.36 no.4
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• pp.341-350
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• 2023

The templated grain growth (TGG) method has gained significant attention for its ability to produce highly textured piezoelectric ceramics with significantly enhanced performance, making it a promising method for transducer and actuator applications. However, the texturing process using the TGG method requires the optimization of multiple steps, which can be challenging for beginners in this field. Therefore, in this tutorial, we provide an overview of the TGG method mainly based on our previous published works, including its various processing steps such as synthesizing anisotropic-shaped templates with size and size distribution control using the molten salt synthesis technique, tape casting, and identifying key factors for proper alignment of the templates in the target matrix system. Our goal is to provide a resource that can serve as a basic reference for researchers and engineers looking to improve their understanding and utilization of the TGG method for producing textured piezoelectric ceramics.

• Food Science and Preservation
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• v.23 no.3
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• pp.422-431
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• 2016

To investigate the causes of the thermal deformations of packaging materials when microwave-heating ready-to-eat sauce products packaged in stand-up pouches, patterns of temperature changes were determined using an infra-red thermal imaging camera, a thermo-sensitive tape, and a fiver-optic thermometer. The temperature distributions of spicy chicken sauce and Indian curry samples in a stand-up pouch were found to be uneven during micrewave heating. A sharp increase in the temperature was detected, especially above the filling layers and in the corners of sealing layers of the package. The temperature measurements using an infra-red thermal imaging camera are restricted to the surface, and therefore might underestimate the actual temperature. Using a thermo-sensitive tape, temperature up to $200^{\circ}C$ were measured in the spicy chicken sauce sample showing package deformation. When the temperature is measured using a fiber-optic thermometer, it is crucial to have precise sensor performance to accurately measure the temperature in a narrow hot-spot area of the package. In this experiment, the fiber-optic thermometer was attached to a GaAs crystal sensor, which obtained more sensitive and accurate temperature measurements than those by a convectional sensor.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.28 no.12
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• pp.792-796
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• 2015

With high integration of electronic components, power inductors are also miniaturized. Recently, thick film processes for small size power inductors were developed and commercialized. However, the thick film process to prepare soft magnetic green sheets was not reported enough. In this study, we used Fe-Si magnetic and CIP (carbonyl iron powders) as starting materials to lead to a bimodal particle size distribution in the sheet. We proposed a newly developed 'Modified slurry preparation process' to get well dispersed condition even at high solid contents. Using the new process, it was possible to prepare a well dispersed slurry over 70 vol% of solid. BYK-103 was better than BYK-111 as dispersant in this slurry and the optimum amount was 0.6 wt%. The optimized slurry was formed into a sheet by tape casting process and then the sheet was laminated. We conformed that small size powder, large size powder, and epoxy resin were well dispersed in the green sheet.

• Applied Science and Convergence Technology
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• v.24 no.5
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• pp.162-166
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• 2015

Linear ion beams have been introduced for the ion beam treatments of flexible substrates in roll-to-roll web coating systems. Anode layer linear ion sources (300 mm width) were used to make the linear ion beams. Oxygen ion beams having an ion energy from 200 eV to 800 eV used for the adhesion improvement of Cu thin films on PET substrates. The Cu thin films deposited by a conventional magnetron sputtering on the oxygen ion beam treated PET substrates showed Class 5 adhesion defined by ASTM D3359-97 (tape test). Argon ion beams with 1~3 keV used for the ion beam sputtering deposition process, which aims to control the initial layer before the magnetron sputtering deposition. When the discharge power of the linear ion source is 1.2 kW, static deposition rate of Cu and Ni were 7.4 and $3.5{\AA}/sec$, respectively.

• Proceedings of the Korean Vacuum Society Conference
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• 2012.08a
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• pp.229-229
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• 2012

Adhesion of Copper film on the aluminum oxide layer formed by anodizing an aluminum plate was enhanced by applying ion beam mixing method. Forming an conductive metal layer on the insulating oxide surface without using adhesive epoxy bonds provide metal-PCB(Printed Circuit Board) better thermal conductivities, which are crucial for high power electric device working condition. IBM (Ion beam mixing) process consists of 3 steps; a preliminary deposition of an film, ion beam bombardment, and additional deposition of film with a proper thickness for the application. For the deposition of the films, e-beam evaporation method was used and 70 KeV N-ions were applied for the ion beam bombardment in this work. Adhesions of the interfaces measured by the adhesive tape test and the pull-off test showed an enhancement with the aid of IBM and the adhesion of the ion-beam-mixed films were commercially acceptable. The mixing feature of the atoms near the interface was studied by scanning electron microscopy, Auger electron spectroscopy, and X-ray photoelectron spectroscopy.

• Korean Journal of Adult Nursing
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• v.15 no.2
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• pp.256-266
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• 2003

Purpose: The aim of this study was to identify the process of experience toward decision making to donate organs. Method: Eleven subjects who registered at the Association for Organ Sharing in Korea were recruited. Using in-depth interviews and tape-recordings, data was collected from Jun. 2001 to Feb. 2002 and the contents of these were analyzed by Glaser's grounded theory analysis method. Result: Basic Social-Psychological Problem(BSPP) of subjects were 'attachment to body' and the core theme, that is Basic Socialization Progress(BSP) were discovered to 'find out what is the meaning of life'. Also it consisted of four steps: 1st 'hesitate', 2nd 'look into self', 3rd 'realize the tie up to self' and last 're-find the meaning of life'. Conclusion: These findings indicate the Korean's Basic Socialization Progress of decision making regarding organ donation, so possible development of promoting decision making is necessary strategies for people who is having his/her potential of organ donation in mind.

• Journal of Korean Institute of Industrial Engineers
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• v.2 no.1
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• pp.45-60
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• 1976

In this study, Multiple Factor Analysis was undertaken for the purpose of substituting General Vocational Aptitude tester for paper tests according to the standardized and partially modified norm, and compared and analyzed these aptitude tests YK Type Working Character test for a test battery. In this analysis, four basis aptitude cluster of AQE was utilized as aptitude cluster, the study for skill was carried out by the method of sampling electronic aptitude cluster in four basis ones, and the parts needed in the process of its analysis were investigated by means of Video-Tape Recording. This paper was performed with sample test by application of the inverse variation curve from learning theory and induced learning rate as a measure of the degree of proficient of technicians, and from the obtained results illustrated optimum newly-production plan of ability program and load program by the use of computer program.