Jung J.S.,Semyung University
MATEC Web of Conferences | Year: 2017
This research aims to make a natural and eco-friendly scarves of Korean and modern style. For the purpose, natural dyeing with safflower, sappan wood, gromwell, amur cork, and areca nut was carried out. As a result, traditional multi-colored scarves were created. And unique scarves of patterns were made by various tie-dyeing methods like tying, folding, wrapping, pleating, and twisting. © The Authors, published by EDP Sciences, 2017.
Ha D.-M.,Semyung University
Korean Chemical Engineering Research | Year: 2017
The combustion properties for the prevention of the fire and explosion in the work place are flash point, explosion limit, autoignition temperature (AIT) etc. The using of the corrective combustion properties of the MSDS (Material Safety Data Sheet) of the handling substance for the chemical process safety is very important. For the safe handling of benzyl alcohol which is widely used in the chemical industry, the flash point and the AIT were measured. And, the lower explosion limit (LEL) of benzyl alcohol was calculated by using the lower flash point which obtained in the experiment. The flash points of benzyl alcohol by using the Setaflash and Pensky-Martens closed-cup testers measured 90°C and 93°C, respectively. The flash points of benzyl alcohol by using the Tag and Cleveland open cup testers are measured 97°C and 100°C. The experimental AIT of benzyl alcohol by ASTM 659E tester was measured as 408°C. The LEL of benzyl alcohol measured by Setaflash closed-cup apparatus was calculated as 1.17 vol% at 90°C. In this study, it was to possible predict the LEL by using the lower flash point of benzyl alcohol which measured by Seta-flash closed-cup tester.
Lee K.M.,Semyung University
Lecture Notes in Engineering and Computer Science | Year: 2016
A smart phone application of a harmful animal scaring system was constructed. The system could be controlled remotely by a smart phone to setup the peripheral devices such as a scarecrow balloon, an audio system and four light lamps. The scaring system consisted of three parts: a smart phone, a scaring control module and peripheral devices. The smart phone was programed to set the peripheral devices by touching the buttons on its screen. The scaring control module was built on an electric circuit board with an ATMEGA's Arduino 328P-PU microcontroller. And the response time between the phone and the control module was measured to be about 200 milliseconds. It was much more convenient to use a smart phone than manually controlling switches.
Kim Y.,Semyung University
Korean Journal of Microbiology | Year: 2013
Candida biofilms are organized microbial communities growing on the surfaces of host tissues or indwelling medical devices, and the biofilms show enhanced resistance against the conventional antifungal agents. The roots of Coptidis chinensis have been widely used for medicinal purposes in East Asia. The present study was aimed to assess the effect of C. chinensis aqueous extract upon preformed biofilms of 10 clinical Candida albicans isolates and the antifungal activities which contribute to inhibit the C. albicans biofilm formation. Its effect on preformed biofilms was judged using XTT [2,3-Bis-(2-Methoxy-4-Nitro-5-Sulfophenyl)-2H-Tetrazolium-5-Carboxanilide)] reduction assay, and metabolic activity of all tested strains was reduced significantly (57.3 ± 14.7%) at 98 μg/ml of the C. chinensis extract. The extract damaged the cell membrane of C. albicans which was analyzed by fluorescein diacetate and propidium iodide staining. The anticandidal activity was fungicidal, and the extract obstructed the adhesion of C. albicans biofilms to polystyrene surfaces, arrested C. albicans cells at G0/G1 as well, and reduced the growth of biofilms or budding yeasts finally. The data suggest that C. chinensis has multiple antifungal effects on target fungi resulting in preventing the formation of biofilms. Therefore, C. chinensis holds great promise for exploring antifungal agents from natural products in treating and eliminating biofilm-associated Candida infection. © 2013, The Microbiological Society of Korea.
Kang J.W.,Korea University |
Kwon O.K.,Semyung University
Applied Surface Science | Year: 2012
We investigated tunable gigahertz-resonators, which is based on the application of a telescoped double-walled carbon-nanotube that can be used repeatedly and operate at a single frequency or have a relatively narrow frequency range, via classical molecular dynamics simulations of a double-walled carbon-nanotube. Two types of telescoped double-walled carbon-nanotube resonators were compared with each other; one was bridge-type and another was cantilever-type, and one side was connected to a position controller in order to achieve a telescoped carbon-nanotube. The frequency bandwidth of our cantilevered type design can exceed that of the bridged type. Our simulations showed that such a system can tune it up its resonance frequency by controlling the length of oscillating carbon-nanotube resonator. © 2011 Elsevier B.V. All rights reserved.
Park S.,Semyung University |
Shin W.-S.,Hanyang University
Physiology and Behavior | Year: 2015
This study aimed to determine whether there might be differences in masticatory performance and eating behaviors by gender and obesity status. Forty eight (24 males; 24 females) non-obese and pre-obese young adults were matched for age, gender, and dental health. Eating behaviors were assessed using the Three-Factor Eating Questionnaire (TFEQ), and chewing performance while eating 152. g of boiled rice was measured using electromyography (EMG). Compared with non-obese participants, pre-obese participants had significantly higher levels of disinhibition according to the TFEQ (P < 0.05 for males; P. < 0.01 for females). Microstructures of chewing performance were significantly different by gender but not by obesity status. Males had a greater bite size (P < 0.05), greater chewing power (P < 0.001) and a faster eating rate (P < 0.05) than females. Females habitually chewed more (P < 0.05) and had a longer meal duration (P < 0.01) than males. Eating rate was positively associated with disinhibition (r=0.490, P. < 0.05) score in males. Bite size (r=- 0.449, P. < 0.05 for non-obese) and chewing power (r=- 0.581, P. < 0.01 for non-obese and r=- 0.446, P. < 0.05 for pre-obese) were negatively associated with disinhibition score. Results suggest that the effects of gender and, in part, obesity on eating responses may be explained as chewing performance. Therefore, gender-specific interventions and counseling aimed at slowing the rate of ingestion could be promising behavioral treatments for obese persons. © 2014 Elsevier Inc.
Kim Y.J.,Korea Institute of Construction Technology |
Choi Y.W.,Semyung University
Construction and Building Materials | Year: 2012
This study is conducted to utilize waste concrete powder (WCP) made as a by-product manufacturing high quality recycled aggregate. The Blaine fineness of the WCP used was 928 and 1360 cm 2/g. As the main characteristic of WCP, it is particle were angular similar to cement, and hydrated products were attached on the surface of particles. In addition, the particle size of WCP was larger than Ordinary Portland Cement (OPC) and in terms of chemical components it had higher SiO 2 content. The viscosity of pastes that contained WCP decreased by up to 62% compared to paste that only used OPC, and the final set time was delayed about 2 h. As substitution rates of WCP increased, the flow value decreased by 30% at the most according to the comparison with mortar that only used OPC. The compressive strength of mortar decreased by up to 73% as level of WCP increased and sorptivity coefficients increased by 70%. According to the test results, it is desirable to keep WCP replacement OPC to below 15%. © 2011 Elsevier Ltd. All rights reserved.
Lee K.M.,Semyung University
Lecture Notes in Engineering and Computer Science | Year: 2013
A home network system with some electric devices was constructed with a power line communication method. The system had two kinds of modems, a central-side and a receive-side. The central-side modem was connected to a controller computer, and the receive-side modem was connected to the electric devices, which were operated by the computer. The devices' setup statuses were manipulated by an external voice recognition controller which was used as a user interface, and connected via Bluetooth communication to the serial port of the computer's COM6. The Bluetooth and the power line communication data rates were 9600 bps and 2400 bps, each. The Polling Process Technique was used for the computer to read the voice recognition result, and to send home-electric-device controlling data to the receive-side modems. The command-recognizing time of the controller was depended on the number of commands. For five commands, the responding time of the communication between the computer and the voice board, was less than 110 milliseconds. Also, the response time of the communication between the computer and the receive-side modem, was less than 100 milliseconds. The home electric device statuses were shown graphically on the computer screen according to the device's setup conditions. It was much more convenient to use a voice command than a key board or a mouse.
Won S.-Y.,Semyung University
Anatomy and Cell Biology | Year: 2016
The aim of this study was to provide accurate anatomical descriptions of the overall anatomy of the superior thyroid artery (STA), its relationship to other structures, and its driving patterns. Detailed dissection was performed on thirty specimens of adult's cadaveric neck specimens and each dissected specimen was carefully measured the following patterns and distances using digital and ruler. The superior thyroid, lingual, and facial arteries arise independently from the external carotid artery (ECA), but can also arise together, as the thyrolingual or linguofacial trunk. We observed that 83.3% of STAs arose independently from the major artery, while 16.7% of the cases arose from thyrolingual or linguofacial trunk. We also measured the distance of STA from its major artery. The origin of the STA from the ECA was 0.9±0.4 mm below the hyoid bone. The STA was 4.4±0.5 mm distal to the midline at the level of the laryngeal prominence and 3.1±0.6 mm distal to the midline at the level of the inferior border of thyroid cartilage. The distance between STA and the midline was similar at the level of the hyoid bone and the thyroid cartilage. Also, when the STA is near the inferior border of the thyroid cartilage, it travels at a steep angle to the midline. This latter point may be particularly important in thyroidectomies. We hope that anatomical information provided here will enhance the success of, and minimize complications in, surgeries that involve STA. © 2016. Anatomy & Cell Biology.
Yoo J.,Semyung University
Ferroelectrics | Year: 2012
The alkaline niobate-based perovskite ceramics (Li,Na,K)(Nb,Ta,Sb)O 3 has been regarded as a new candidate of lead-free piezoelectric materials due to its excellent piezoelectric properties. In this study, Li 0.02(Na0.55K0.45)0.98(Nb 0.77Ta 0.18 Sb0.05)O3 (abbreviated as LNKNTS) piezoelectric ceramics were fabricated by a conventional solidstate reaction method at various calcinations temperature and then, their dielectric and piezoelectric properties were investigated. At the calcinations temperature of 870°C and sintering temperature of 1140°C, the optimum values of density = 4.736g/cm3, kp = 0.423, Qm = 65, εr = 1545 and d33 = 256 pC/N, were obtained, respectively. Taking into consideration above physical properties, it is considered that this composition is applicable to lead-free haptic piezoelectric actuators. Copyright © Taylor & Francis Group, LLC.