• Journal of Practical Engineering Education
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• v.15 no.1
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• pp.127-132
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• 2023

Authors report the performance indicator of Roll to Roll MC (hereinafter referred to as RTR) through experiment that it is possible to process 2.0G acceleration, which cannot be coped with in the existing FPCB RTR, by reducing the weight of the Dancer roll system and controlling the torque using the servo motor. Proposed dancer roll system provides uniform tension to FPCB by solving problems such as high rotation speed, heat generation, and low torque, which were impossible to achieve with the conventional magnet clutch type RTR. Through the development of a lightweight processing method for rolls using magnesium material and the development of a torque control algorithm for servo motor, torque stability also increased. Due to the enabling technology developed in this study, the reaction speed of the dancer roll was improved and the target speed was achieved as well.

• Smart Media Journal
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• v.13 no.8
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• pp.67-78
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• 2024

The purpose of this study is to investigate the changes and developments in the administrative system, status, and role of public libraries in our country, and to analyze the spatial composition status according to the inter-cooperation system of public libraries located in Gwangju Metropolitan City. For this purpose, the study referenced the required space and area standards according to the status and role presented in the 2022 Public Library Construction and Operation Manual. Floor plan analysis and spatial composition analysis were conducted on the central libraries of the five districts in Gwangju Metropolitan City. The analysis results revealed redundancies and inefficiencies in the spatial composition of public libraries with similar purposes. It was found that securing the area of public libraries according to the hierarchy of administrative districts is necessary to provide smooth library services to local residents. Additionally, with the opening of the representative library in Gwangju Metropolitan City, the reconfiguration of the existing central library spaces was deemed necessary. This study can be used as a foundational resource for the efficient operation and construction of public libraries in the future.

• Textile Coloration and Finishing
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• v.31 no.3
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• pp.135-146
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• 2019

A series of azo based disperse dyes were synthesized and applied to polyester(PET) fiber in supercritical carbon dioxide($ScCO_2$). Various aniline derivatives were used as diazo component and coupled with glycine ethylester or carbonic acid ethylester derivatives to give azo based disperse dyes. Depending on the various diazo substituents, absorption maxima varied from 415 to 529nm in acetone. Dyeing in $ScCO_2$ was carried out at $120^{\circ}C$ and 250bar pressure for 2hrs with 0.5% o.w.f. of dye concentration. Dyed PET fiber had excellent brightness and good light, washing and perspiration(acid/alkali) fastness properties.

• Journal of the Korean Applied Science and Technology
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• v.38 no.5
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• pp.1229-1240
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• 2021

Ginkgo (Ginkgo biloba L.) seeds, called 'Baekqwa', were extracted from 70% ethanol to investigate the whitening effect and to confirm the application potential as a cosmetic material. Ginkgo seed ethanol extracts (GBE) were treated with B16F10 melanoma cells, and melanin contents and tyrosinase, which is the main enzyme concerning the synthesis process of melanin, inhibitory activity were confirmed. As a result, there were inhibited in a concentration-dependent manner, and GBE also significantly reduced the protein expression and mRNA levels of tyrosinase, tyrosinase-related protein-1, -2 (TRP-1, -2), and their upstream transcription factor, microphthalmia-associated transcription factor (MITF). These results suggest that GBE could be used as an effective whitening agent that has an inhibitory effect on melanin production by regulating the expression and degradation of MITF in melanocytes.

• Journal of the Korea Society of Computer and Information
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• v.25 no.12
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• pp.243-251
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• 2020

This study is intended to verify the efficiency of the information system by using the navigation application in case of fire. In the demonstration scenario simulation, it was assumed that a fire occurred 6th floor in Korea Institute of Industrial Design Promotion located in C city, K province. Eighty juniors students from K University's department of paramedics of science participated. As a result of the experiment, the demonstration simulation using the navigation application showed that the evacuation time was faster than the case of evacuation guidance in a fire situation. The need for a fire prevention system and fire prevention awareness before and after the implementation of the demonstration scenario simulation increased the need for a fire prevention system and fire prevention awareness score after the experiment.

• The Journal of the Korea institute of electronic communication sciences
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• v.16 no.3
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• pp.471-476
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• 2021

Soft magnetic composite (SMC) materials based on powder metallurgy have a number of advantages over the conventional electrical steel sheets commonly used in electric machines. Thus, technologies related to these materials have shown significant improvement in recent years. In general, SMCs are magnetically isotropic owing to the shape of the powder, which makes them suitable for the construction of electric machines with three-dimensional flux and complex structures. However, the materials with isotropic magnetic properties (such as SMCs) have complex vector hysteresis; thus, it is very difficult to predict accurate loss properties. Therefore, we manufactured ring-type specimens of electrical steel sheets and SMC, which analyzed their magnetic properties according to the specimen size, and performed the electromagnetic field analysis of a high-speed permanent magnet (PM) motor driven at 800 Hz or higher using the measured magnetic information to compare the core loss of the motor. The reliability of this paper has been verified by measuring the efficiency after manufacturing the motor.

• Proceedings of the Plant Resources Society of Korea Conference
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• 2022.09a
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• pp.37-37
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• 2022

밀은 세계 3대 작물로 국내 1인당 소비량은 지속적으로 증가하고 있다. 하지만 국내 밀의 유전적 배경 확대와 기후변화 신속 대응을 위한 국내 밀 유전자 풀의 확장은 밀의 질적 향상을 위해 매우 중요한 목표이다. 국내 자생 갯그령(Leymus mollis)은 해안가에서 번식하는 영년생 식물로 뿌리줄기를 이용한 왕성한 번식력을 가지고 있다. 또한, 해안가의 뜨겁고 염에 대한 적응성과 저항성을 가지고 있다. 이러한 특성은 밀 유전자 풀의 확장에 매우 유용할 것이다. 국내 밀 재배지 한계 극복을 위한 간척지 재배가 가능한 내염성 강화 밀 자원 개발을 위하여 모본인 보통 밀(Triticum aestivum L., Chinese Spring)과 부본인 갯그령을 원연교배하였다. 갯그령과 보통 밀의 원연 교배를 통한 종자 형성은 매우 어려우나 불가능한 것은 아니며, 최종적으로 10개의 교배 종자를 얻어 F₁ 식물체로 생장하는 과정에서 5 식물체는 고사하였고, 나머지 5 식물체는 영년생 특성인 뿌리줄기에 의해 새로운 줄기가 출현하는 것을 확인하였다. 또한, 갯그령의 DNA를 이용한 genomic in situ hybridization 방법으로 F₁ 식물체에서 갯그령의 염색체가 밀의 유전적 배경에 이입된 것을 확인하였다. F₂ 식물체는 모본인 보통 밀보다 긴 수장과 간장을 나타내고 이삭 수는 많았지만, 출수기는 보통 밀보다 3주 이상 늦어지는 것을 확인하였다. 내염성 평가를 위하여 F₂ 종자를 2% 소금물에서 발아시켜 생육이 좋은 식물체를 선발하여 50 cm 투명 아크릴 원통에 이식하고 2% 소금물을 지속적으로 관개하였다. 내염성 강화 F₂ 식물체는 염에 감수성을 보인 식물체에 비하여 상대적으로 긴 이삭과 종자 형성을 보였으며, 감수성 식물체는 종자 형성이 이루어지지 않았다. 또한, 내염성 강화 F₂ 식물체는 감수성 식물체에 비하여 좋은 뿌리의 신장과 천근성을 보였다. 이러한 갯그령의 식물학적 특성이 이입된 계통은 기후변화 대응, 환경 적응성 강화, 및 근권 강화에 좋은 작물 소재로 이용할 수 있다고 생각한다.

• Journal of Mushroom
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• v.19 no.3
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• pp.210-215
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• 2021

For sterilization of microorganisms of the Listeria genus contaminating enoki mushroom, pilot mushroom grower equipped with air sterilization devices were developed. Sterilization experiments were performed using physical and chemical treatments. Internal temperature and humidity were controlled, maintaining 6.62℃±0.30 in the upper shelves, 6.46℃±0.24 in the middle shelves, and 6.48℃±0.25 in the lower shelves. Humidities were 79.97%±4.42, 79.43%±4.06, and 79.94±4.30%, respectively, with a temperature setting of 6.5℃, and a relative humidity of 75%. A suitable enoki mushroom cultivation stage for air sterilizer application was during the growth stage, with temperature in the 6.5~8.5℃ range, and humidity of 70~80%. At these same internal conditions, the ozone concentration in the mushroom cultivator was found to be 160 ppb during ion-cluster generator operation. After physical sterilization, the Listeria innocua survival rate was 0.1 to 0.9% using ion cluster sterilization, and 9.3 to 10.6% using UV air sterilization. The Listeria innocua survival rates on different materials were 9.3~10.6% on the metal specimen, and 9.9~16.2% on the plastic wrapper. The survival rate was particularly high on the rough side of the plastic wrapper. Ion cluster air sterilization is a labor-saving and effective method for suppressing the occurrence of Listeria bacteria on mushroom growers walls and shelves. For the plastic wrapper, chemical sterilization is more effective than physical sterilization.

• Science of Emotion and Sensibility
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• v.20 no.2
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• pp.171-178
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• 2017

'Smart Sensibility Mat (SSM)' was developed and manufactured for positive sensibility of newborn with fiber, digital, and sensibility technology to reflect features and advantages of kangaroo care. For tactile stimuli, the tube of the silicon material to provide a constant temperature of $32^{\circ}C$ was inserted into the mat and connected to the water-thermostat. To provide a uniform temperature throughout the mat, the fabric by the inserting conductive yarn was attached to the mat surface. After wrapping the mat with cotton pad, the polyurethane foam used as medicine in order to similar to the human skin was bonded to the surface of the mat. To provide the auditory stimuli of a level of 30dB with mother's heartbeat sounds and voice recorded in advance, the Bluetooth speaker was inserted into the mat. To investigate the effects of SSM, 10 newborns who born within two weeks were involved in this experiment. While the baby was lying on each of the general mat (GM) and SSM, the baby's physiological signals-heart rate, breathing rate, temperature- were measured and then, those were conducted t-test to examine the difference between the signals of SSM and GM. The results were as follows: heart rate (t=8.131, p<.001) and respiratory rate (t=7.227, p<.001) among the physiological signals of SSM decreased significantly than GM within the normal range. Temperature (t=1.062, p=0.292) at SSM showed a tendency to decrease than GM within the normal range. This means the tactile stimuli and the auditory stimuli providing from SSM give stable physiological responses. Thus, SSM leads to have psychological comfort and stability of newborns.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.26 no.10
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• pp.841-850
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• 2015

With the rapid progress of electronics and radio communication technology, human enjoys greater freedom in information communication. However, EMW(Electro-Magnetic Wave) environments have become more complicate and difficult to control. Thus, international organizations, such as the American National Standard Institution(ANSI), Federal Communications Commission(FCC), the Comite Internationale Special des Perturbations Radio Electrique(CISPR), etc, have provided standard for controlling the EM wave environments and for the countermeasure of the electromagnetic compatibility(EMC). In this paper, fabrication of the smart EMW absorber which has heat radiating function and high performance absorption abilities were suggested. Furthermore, we prospected future smart EMW absorbers. The designed smart EMW absorber is fabricated following process. Firstly, we applied high temperature heat treated to a mixture of Iron-oxide($Fe_2O_3$) and ceramics. Secondly, we applied low temperature heat treated to the mixture of heat treated material and a carbon material. Lastly, we made apertures on the absorber. The designed smart EM wave absorber has the absorption ability of more than 20 dB from 2 GHz to 2.45 GHz band, respectively. Thus, it is respected that these results can be applied as various EMC devices in electronic, communication, and controlling systems.