• Journal of Microbiology and Biotechnology
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• v.17 no.5
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• pp.853-857
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• 2007

The semi-outdoor cultivation of Spirulina platens is was attempted using an underground-water-based medium. Occurrence of contaminant organisms such as Chlorella sp. and Chlamydomonas sp. was not found from a microscopic observation and bacteria were not detected from denaturing gradient gel electrophoresis(DGGE) analysis of PCR-amplified 16S rDNA during the cultivation, owing to pH control and the high quality of the underground water. The mean productivity was high at $10.5g/m^2/d$ with a range of $4.2-12.3g/m^2/d$ despite the unfavorable weather conditions of the rainy season. The cultivated S. platens is included a normal protein content of 58.9%. Consequently, the underground water improved the biomass productivity and the biomass quality because of an abundant supplementation of natural minerals and through a contaminant-free culture.

• International Journal of Industrial Entomology and Biomaterials
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• v.48 no.2
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• pp.67-77
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• 2024

This study aims to assess the efficacies of exogenous enzymes, derived from invertebrate gut-associated microbes, as feed additives, in reducing volatile organic compound (VOC) emissions using an in vitro pig intestine continuous fermentation system. An in vitro continuous fermentation model was used to simulate a comparable bionic digestion system by co-reacting feed, enzymatic additives (arazyme, mannanase, and xylanase, derived from the gut bacteria of Nephila clavata, Eisenia fetida, and Moechotypa diphysis, respectively), and gastrointestinal microbes, followed by an analysis of their correlations. A significant correlation was observed between exogenous enzyme supplementation and reduced VOC emissions in the fecal phase of continuous fermentation (p < 0.05). The concentration of VOCs decreased by 3.75 and 2.75 ppm in the treatment group following arazyme and multi-enzyme supplementation, respectively, compared to that in the control group (7.83 ppm). In addition, supplementation with arazyme and multiple enzymes significantly affected the microbial composition of each fermentation phase (p < 0.05). In particular, Lactiplantibacillus pentosus and Pediococcus pentosaceus, which changed in abundance according to arazyme or multi-enzyme supplementation, exhibited a positive relationship with VOC emissions. These results suggest that exogenous enzymes derived from invertebrate gut-associated bacteria can be efficiently applied as feed additives, leading to a reduction in VOC emissions.

• Tribology and Lubricants
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• v.28 no.4
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• pp.167-172
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• 2012

The turbo pump of a liquid rocket engine is composed of three main parts: the oxidizer pump, fuel pump, and turbine. Liquid oxygen ($LO_X$) is the working fluid in the cryogenic environment in the oxidizer pump, but tests are usually performed using liquid nitrogen ($LN_2$), which has a boiling point similar to that of $LO_X$ but is comparatively safer and easier to use for the test. In this study, a bearing test rig is developed and its performance is evaluated using a cryogenic ball bearing with $LN_2$ as the working fluid. Verifying the performance of the bearing test rig is crucial for ensuring correct working of the turbo pump unit in the liquid rocket engine. A stable test rig for the bearing in a cryogenic environment makes the bearing technology enhance its reliability. The test results show that the system operates stably and the requirement of performance time of 500 s is met. The test results of temperature, motor speed, and torque are discussed. The developed cryogenic bearing test rig is expected to help in widening knowledge and expanding research on ball bearings in the future.

• Proceedings of the Korea Society of Information Technology Applications Conference
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• 2002.11a
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• pp.461-467
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• 2002

Signals reduced from the brain had been considered as a noise that is caused by the stochastic process until 1980. The recent non-linear dynamic theory researches, however, reported that these signals are meaningful and deterministic chaos signals in which they show how the brain deals with various information Since this report, a wide range of researches has been carried out and still in progress. Thus, by using the correlational dimension, one of the non-linear analytical methods, the characteristics of the brain signals can be analyzed. In this thesis, the scent of lavender, which stimulates the olfactory sense, is introduced to measure EEG with the International 10-20 electrode system on 16 channels, and to analyze the interrelationship between the original signals before the stimulation and the changed signals after the stimulation. Finally, the effect of the scent stimulation to the brain is analyzed. The purpose of this thesis is to apply these analyzed results to the computerized mapping of the brain signals and possible ways of specifying the source of the brain signals through various medical applications.

• Proceedings of the Korea Society for Industrial Systems Conference
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• 2002.11a
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• pp.461-467
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• 2002

Signals produced from the brain had been considered as a noise that is caused by the stochastic process until 1980. The recent non-linear dynamic theory researches, however, reported that these signals are meaningful and deterministic chaos signals in which they show how the brain deals with various information Since this report a wide range of researches has been carried out and still in progress. Thus, by using the correlational dimension, one of the non-linear analytical methods, the characteristics of the brain signals can be analyzed. In this thesis, the scent of lavender, which stimulates the olfactory sense, is introduced to measure EEG with the International 10-20 electrode system on 16 channels, and to analyze the interrelationship between the original signals before the stimulation and the changed signals after the stimulation. Finally, the effect of the scent stimulation to the brain is analyzed. The purpose of this thesis is to apply these analyzed results to the computerized mapping of the brain signals and possible ways of specifying the source of the brain signals through various medical applications.

• Preventive Nutrition and Food Science
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• v.13 no.3
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• pp.212-218
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• 2008

We extracted red ginseng with various alcohol concentrations and evaluated total carbohydrate, uronic acid, polyphenols compounds and ginsenoside contents, and yields of alcohol extract. The water extraction (0% alcohol extraction) showed a high level of total carbohydrate content. 10% and 20% alcohol extraction showed the highest uronic acid contents (7,978.8 and $7,872.7\;{\mu}g/mL$ of extract, respectively). The efficiency order of the red ginseng extract (RGE) preparations in liberating polyphenols was: $0{\sim}50%$ alcohol${\geq}\;60%$ alcohol> $70{\sim}90%$ alcohol. Solid contents in RGE were decreased with increased alcohol concentration; the same tendency as with the results of total carbohydrate content. Total ginsenoside contents in $20{\sim}50%$ alcohol extracts showed similar levels ($442,962.9{\sim}47,930.8\;{\mu}g/mL$ of extract). Water extraction showed the lowest ginsenoside content ($14,509.4\;{\mu}g/mL$ of extract). The ginsenoside contents at above 60% alcohol were decreased with increased alcohol concentration. Generally, ginsenoside (Rg2, Rg1, Rf, Re, Rd, Rb2, Rc and Rb1) contents were increased with increased alcohol concentrations. However, Rg3 content was decreased with increases in alcohol concentration.

• Journal of Convergence for Information Technology
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• v.7 no.5
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• pp.129-135
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• 2017

In this paper, we propose a system to monitor the condition of elderly people who are uncomfortable by using smart-phone and biometric sensor at any time and for care-givers to provide with the best medical service anytime and anywhere. The proposed system monitors the status of the elderly through various bionic sensors installed in the hospital ward based on the Arduino system and not only provides the physiological and medical services required by the elderly, but also informs the guardian so that he can cope with the emergency. In conclusion, this paper suggests that a reading light used by elderly people can operate as a home server with a biosensor using Arduino and Android applications (Apps.), and the smart-phone of care-givers is configured as a remote management and a emergency call system. Therefore, this study suggests important ways to improve the satisfaction of medical service for the both elderly people and care-givers of chronic diseases in the future.

• Journal of Physiology & Pathology in Korean Medicine
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• v.26 no.1
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• pp.1-9
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• 2012

Five mimic-animal boxing(五禽戱, FAB) is physical fitness exercises conducted by imitating the motions of tiger, deer, bear, monkey, and bird, devised by the famous doctor Hwa-Ta(華陀) in the Three Kingdoms of China. FAB is one of bionic-physical and breathing exercises(傍生導引) by combined automassage as a practice for health care. Although FAB have effects of health control and medical treatment, but interrelationship of five animals(五禽) of FAB and five viscera(五臟) of five elements(五行) is complicated. So, the present was designed to investigate the progress of FAB, movement-feature of FAB, and the interrelationship of five animals and five viscera. further I will develop value by sports-treatment medicine in oriental medicine. The results were as follows ; FAB is physical exercises of dynamic exercises and new-dynamic exercises. Feature of China-FAB have each movement by imitating the motions of each animals, movements of Formosa-FAB were mixed. In philosophical viewpoint, Five animals (tiger, deer, bear, monkey, bird) were attached to metal, wood, water, earth, fire of five elements, and lung, liver, kidney, spleen, heart of five viscera. In viewpoint of breathing exercises, Five animals (tiger, deer, bear, monkey, bird) were attached to water, wood, earth, fire, metal of five elements, and kidney, liver, spleen, heart, lung of five viscera. Although FAB have effects of health control and medical treatment, FAB have indication and contraindication. Therefore, I think that mechanism of treatment should reason with Oriental medicine doctor in FAB.

• Journal of Distribution Science
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• v.13 no.1
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• pp.7-18
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• 2015

Purpose - This study integrates a corporate competition system with a bird predation system to examine how organizational strategic adjustment capacity influences firm performance. By proving the prominent effects on performance, a financial vector is constructed to represent corporate strategic adjustment results, and an operation capacity vector is constructed, which can be categorized as a parameter for locating birds. All these works help us to propose a new method of investment, the portfolio decision model based on the strategic adjustment capacity. Research design, data, and methodology - Strategic adjustment capacity can be decomposed into three aspects: the organizational learning capacity from the top firms, the extent to which firms maintainor rely on the best operational capacity vector in history, and the ability to eliminate the disadvantages or retain the advantages of the operation capacity vector from the previous year. The method of solving cyclic equations is designed to evaluate strategic adjustment. Firms manufacturing specialized equipment are chosen to test the effects of the strategic adjustment capacity on three aspects of firm performance. Results - There is a positive correlation between the capacity to learn from the best firms and performance improvement. The relationship between the dependence or maintenance of a firm's advantages and performance improvement is a U-shape curve, and there is no significant effect of inertial control on performance improvement. Conclusions - A firm's competition system is a sophisticated adaptation, and competitive advantage and performance can be investigated based on the principles of competition in nature.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.37 no.5
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• pp.554-561
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• 2024

Micro light-emitting diodes (µLEDs) have been utilized in various fields such as displays, and smart devices, due to their superior stabilities. Since the applications of the µLEDs have been extended to medical devices and wearable sensors, excellent optical properties and uniformity of the µLEDs are important. Hence, several researchers have investigated to enhance the optical efficiency of the µLEDs through micro/nano lens. However, the reported methods for realizing the micro/nano lens have some drawbacks such as complex and high-cost manufacturing processes. Herein, we developed µLEDs with 3D-printed hydrogel microlenses. The printed hydrogel had high transparency and excellent adhesive strength, allowing it to attach onto top surface of the µLEDs without any additional adhesives. Microscale printing technology using a 3D printer achieved quick and fine printing in desired shapes and arrangements, showing the possibility of mass production. The 3D-printed microlens can be applied to improve not only the optical properties of µLEDs but also other optical devices.