• Journal of Microbiology and Biotechnology
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• v.17 no.5
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• pp.847-852
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• 2007

This study investigated an efficient method for the extraction of astaxanthin from the red yeast Xanthophyllomyces dendrorhous. The extraction process comprised three steps: 1) cultivating the yeast; 2) treating the yeast culture suspension with microwaves to destroy the cell walls and microbodies; and 3) drying the yeast and extracting the astaxanthin pigment using ethanol, methanol, acetone, or a mixture of the three as the extraction solvent. Ultimately, various treatment tests were performed to determine the conditions for optimal pigment extraction, and the total carotenoid and astaxanthin contents were quantified. A frequency of 2,450 MHz, an output of 500 watts, and irradiation time of 60 s were the most optimum conditions for yeast cell wall destruction. Furthermore, optimal pigment extraction occurred when using a cell density of 10g/l at $30^{\circ}C$ over 24 h, with a 10% volume of ethanol.

• 한국방재학회:학술대회논문집
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• 2008.02a
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• pp.735-738
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• 2008

Various characteristics of creek were not considered in designing creek for a long time. As result of that, a lot of reverse functions have been present in creek. In this study, a presentation of creek damage was investigated and differences river form creek design standards were analyzed. The damage of creeks accounts for 37.3 percent of total damage of rivers over the last 6 years. Besides, government should spend more money in restoring creeks. Considering that maintenance rate of domestic creeks is 37 %, counterplan should be prepared to prevent the damage of creeks. There are many kinds of causes in destroyed creek round. Specially, most damage was secondary that was caused by increase of flood elevation according to decrease in conveyance, local scour around structures, and failures because of inappropriate structures such as bridge, culvert, crossbeam, and drop in creek. These destroy types are in bend area. However, current creek design standards do not suggest solutions to prevent damages. Currently, there are no standards for bridge, and appropriate hight and width of culvert. Standards for crossbeam and drop could not reflect characteristics of creek. Therefore, it is need to improve the creek design standards for appropriate design and construction. That could improve flood control and prevention of creeks.

• Journal of the Korea Institute of Military Science and Technology
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• v.14 no.6
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• pp.1009-1017
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• 2011

A Ballistic Missile(BM) is a missile that follows a sub-orbital ballistic flightpath with the objective of delivering one or more wardheads to a predetermined target and An Anti-Ballistic Missile(ABM) is a missile designed to destroy a ballistic missile before reaching its target. The main objective of this study is to assess the requirement of ABM by considering both flight characteristic of the SCUD-B/C, Nodong missiles and intercept performance of ABM in the Lower tier Ballistic Missile Defense(BMD). The Ballistic Missile's flight characteristics, such as trajectory, velocity etc., are estimated by simulation using the physical motion equations. The requirement of ABM is calculated by evaluating whether the BMD forces can defend those when the ballistic missiles attack prime facilities.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2017.10a
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• pp.61-62
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• 2017

In this study, we introduce some main functions and specifications of a recently commercialized potable compact high voltage generator. USB killer has been designed to test surge protection circuitry of electronic equipments using USB ports. USB killer transforms 5V DC power supplied by USB port into a sufficiently high voltage over 200V DC through oscillator, transformer, voltage multiplier, and rectifier. The power charged in a high-capacity condenser can be applied back into the electronic equipments as an electric shock to destroy them or test protection circuits. USB killer is a readily available item, and one can test a variety of electronic equipments. We introduce some test results known over the internet and those obtained from our tests.

• Proceedings of the Korean Society of Tribologists and Lubrication Engineers Conference
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• 2000.11a
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• pp.332-340
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• 2000

Friction properties of automotive brake pads containing different types of abrasivess were investigated. Five different abrasives, including o-quartz, magnesia, magnetite, alumina, zircon, were employed in this investigation and size effects of the abrasives on friction characteristics were also studied using 1, 50, 140$\mu\textrm{m}$ size zircon. Experimental results showed that the hardness and size of these abrasive particles were strongly related to friction behaviors and wear mechanisms. Harder and smaller abrasives showed higher friction coefficient and more wear. The surfaces of friction materials with different sizes of abrasives showed that two different modes of abrasion (two-body and three-body abrasion) appeared during sliding. Considering the above results, abrasive materials were thought to destroy transfer film and the extent of the destruction depends on the types and sizes of abrasive particles. A mechanism of the wear mode transition (two-body to three body abrasive motion) was suggested considering the binding energy and friction energy in terms of abrasive particle size.

• Journal of Korean Society on Water Environment
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• v.23 no.4
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• pp.504-511
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• 2007

Built-out issue of copper processing appearing recently in the Paldang watershed is a critical problem to deteriorate the basic framework of national water management policy as well as to be simply a copper-related problem. Up to now, Korea government has invested hard and relevant upstream areas have been victimized readily in a variety of field to comply its goal of 'Safe Water Supply'. Because of the reason, the desirable water quality level of the Paldang watershed has been maintained regardless of its dense population. Paldang drinking water management policy is based on residents' understanding which is considered as a 'social capital'. The issue raised in the aspect of water quality management policy should be reviewed on the basis of the 'social capital' concept. One regarding semiconductor industry as a potential industry to export many products in 10 years insists that the industry not be a simple private business but be a prominent part for national competitiveness. There is no doubt about this opinion. However, a nation should support environmental right-to-life of its people prior to any other tasks. In other words, it is really risky to give up people's right due to economic benefits. Therefore, it should not happen to trade 'life', the dignity of man, with national competitiveness which is likely to be preferred in these days. In addition, coherent policy not to destroy 'social capital' promoting Paldang drinking water resource management policy should be maintained.

• Journal of Food Hygiene and Safety
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• v.3 no.4
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• pp.203-209
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• 1988

This study was performed to develop the simple and rapid determination method of preservatives in Yogurt and Soybean.sauce. 1. The analytical method by HPLC system was as follow: The sample was diluted, centrifuged, filtered, if necessary, and analyzed by HPLC system with UV detector. 2. The analytical method by GLC system was as follow: The sample was extracted directly with ether, added cone. sulfuric acid to destroy emulsion and analyzed by the GLC system with FID. 3. The recovery rates of preservatives by the above methods were higher than 99.0 %. 4. Total running time for the above methods was less than 50 minutes. Especially, the running time for dilution method by HPLC system was one-third of that for GLC method.

• Korean Journal of Bronchoesophagology
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• v.4 no.1
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• pp.85-90
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• 1998

The role of the ECP(Eosinophilic cationic protein) is still unknown in the allergic rhinitis. In bronchial asthma, ECP can induce the exposure of the neuropeptidergic nerve to environments destroying the bronchial mucosa, aggravating the bronchial hypersensitivity and delay the mucociliary clearance. In the clinical aspect, we can (md that patients with perennial allergic rhinitis sometimes have sinusitis. The purpose of this article is to evaluate whether mucosal damage by ECP can play a role to develop the sinusitis by delaying the mucociliary clearance, and relationship between long symptom duration of allergic rhinitis and mucociliary clearance. In 32 perennial allergic rhinitis patients, we elucidated there is correlation among ECP presence, mucociliary clearance, sinusitis, and symptom durations. The obtained results were as follows : 1. ECP appeared in all mucosa of each specimen. 2. Mean mucociliary clearance time is 6 mins. 12 sec. in allergic patients with sinusitis, 6 mins. 36 sec in allergic patients without sinusitis. 3. n out of 32 cases have mucosal destruction. 4. Symptom duration is not correlated with the development of sinusitis. This study suggests that ECP may destroy the mucosa in allergic rhinitis and the mucociliary clearance of allergic rhinitis is not related to sinusitis and symptom dotation. Therefore development of sinusitis in allergic rhinitis seems not to be caused by delaying of mucociliary clearance due to mucosal destruction, but by some other factors.

• Wind and Structures
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• v.32 no.4
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• pp.309-319
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• 2021

The vortex-drift pattern over a girder surface, actually demonstrating the complex fluid-structure interactions between the structure and surrounding flow, is strongly correlated with the VIVs but has still not been elucidated and may be useful for modeling VIVs. The complex fluid-structure interactions between the structure and surrounding flow are considerably simplified in constructing a vortex model to describe the vortex-drift pattern characterized by the ratio of the vortex-drift velocity to the oncoming flow velocity, considering the aerodynamic work. A spring-suspended sectional model (SSSM) is used to measure the pressure in wind tunnel tests, and the aerodynamic parameters for a typical streamlined closed-box girder are obtained from the spatial distribution of the phase lags between the distributed aerodynamic forces at each pressure point and the vortex-excited forces (VEFs). The results show that the ratio of the vortex-drift velocity to the oncoming flow velocity is inversely proportional to the vibration amplitude in the lock-in region and therefore attributed to the "lock-in" phenomena of the VIVs. Installing spoilers on handrails can destroy the regular vortex-drift pattern along the girder surface and thus suppress vertical VIVs.

• Cross-Cultural Studies
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• v.26
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• pp.297-319
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• 2012

We all know how beautiful our wild and it's importance to our living planet Earth. But did you realise the speed at which man himself is damaging it's unique natural habitat. We are well on our way to destroy our forests, plants, wetlands. We are polluting our oceans and seas. This way, we're driving numerous animal species, plant species and many others into extinction. Everyone should be aware of the importance of our natural environment. We live in the period of echocide. Why we need nature to survive and how we can deal with the environmental problems we face. This paper has the purpose to reform city's environment. Because, Metropolis and megalopolis are the principal cause of environmental disruption. To reform the city is needed to consider digital technology in our age. In the face of economic and cultural globalization, many have argued that we live an increasingly placeless world. However, as a growing number of cities participate and compete in key marketplaces of advanced capitalism, the spectacle of the city is more than ever a significant medium of communication in its own right. In doing so, this work is focused specifically on the dimension of city's media environment. To that end, the paper examined U-City and U-Eco city. In this study, we will introduce the study on model of U-Eco City as one way for the eco-freindly future city.