• Geosystem Engineering
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• v.21 no.6
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• pp.326-334
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• 2018

Underground water-sealed gas storage caverns have become the primary method for strategic storage of LPG. Previous studies of excavation blasting effects on large-scale underground water-sealed gas storage caverns are rare at home and abroad. In this paper, the blasting excavation for underground water-sealed propane storage caverns in Yantai was introduced and field tests of blasting vibration were carried out. Field test data showed that the horizontal radial velocity had a major controlling effect in the blasting vibration and frequencies would not cause the vibration velocity concentration effects. In terms of the influence of blasting vibration on adjacent caverns, the dynamic finite element model in LS-DYNA soft was established, whose reliability was verified by field test data. The numerical results indicated the near-blasting side was primary zone for the structural failure and tensile failure tended to occur in the middle of the curved wall on the near-blasting side. Meanwhile, the safety criterions for adjacent caverns based on stress wave theory and according to statistic relationship between peak effective tensile stress and peak particle velocities were obtained, respectively. Finally, with Safety Regulations for Blasting in China (GB6722-2014) taken into account, a final safety criterion was proposed.

• Journal of Ginseng Research
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• v.28 no.4
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• pp.215-218
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• 2004

This study were conducted to investigate the viability and germination of dehisced Panax ginseng seeds stored for long period in the storage chamber with $5^{\circ}C\;and\;30{\%}$ humudity. The staining reaction times for viability test were 150 min, 90 in, 60 min at $0.1{\%},\;0.5{\%}\;and\;1{\%}$ triphenyltetrazolim chloride(TTC), respectively. the more the storage period, the less the healthy seeds ratio. It was $96.6{\%},\;89.2{\%},\;63.4{\%}$ for 1-year storage, 7-years storage, 9-years storage, respectively. Germination ratio were $84.0{\%},\;80.5{\%},\;73.5{\%},\;2.5{\%}$ for 1-year stroage, 6-years storage, 7-years storage and 9-years storage, respectively. Therefore it was confirmed that ginseng seed can be stored up to 6-7 years.

• Journal of Food Hygiene and Safety
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• v.11 no.3
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• pp.189-196
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• 1996

Based on microbiological-chemical test results under simulated time-temperature conditions, total plate count, coliform, and volatile basic nitrogen were selected as effective quality indicators for estimating probable shelf-life on Kim Pab dosirak marketed in convenience stores, and shelf-life at each storage temperature was calculated from regression equation between effective quality indicator standard limit and storage time. Estimated shelf lives of Kim Pab Dosirak were 17, 3 and 2 hours respectively under 1$0^{\circ}C$, 2$0^{\circ}C$ and 3$0^{\circ}C$. Because shelf-life was especially affected by intial values, regression analysis between initial effective quality indicator values and storage hours was performed for the estimation of probable shelf-life on Kim Pab during storage at 10, 20, or 3$0^{\circ}C$.

• Journal of Electrical Engineering and Technology
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• v.6 no.4
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• pp.447-458
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• 2011

In this paper, a novel flywheel energy storage device, called the flexible power conditioner, which integrates both the characteristics of the flywheel energy storage and the doubly-fed induction machine, is proposed to improve power system stability. A prototype is developed and its principle, composition, and design are described in detail. The control system is investigated and the operating characteristics are analyzed. The test results based on the prototype are presented and evaluated. The test results illustrate that the prototype meets the design requirement on power regulation and starting, and provides a cost-effective and effective means to improve power system stability.

• Proceedings of the KIEE Conference
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• 2008.10c
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• pp.208-210
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• 2008

LRT System Application Project is performed for the purpose of technical advancement and stabilization of K-AGT system from the viewpoint of practical use and commercialization. For those purpose, the performance test and evaluation procedure for K-AGT signaling system are developed, and the scheme of verifying the performance and function of signaling system under multi-train and driverless control environment is being conducted. For the multi-train operation in K-AGT test track, we applied the regenerative energy storage system in addition to the existing electric facilities. This paper present the design, manufacturing, and testing results of regenerative energy storage system.

• Proceedings of the KSR Conference
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• 2008.11b
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• pp.325-330
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• 2008

LRT System Application Project is performed for the purpose of technical advancement and stabilization of K-AGT system from the viewpoint of practical use and commercialization. For those purpose, the performance test and evaluation procedure for K-AGT signaling system are developed, and the scheme of verifying the performance and function of signaling system under multi-train and driverless control environment is being conducted. For the multi-train operation in K-AGT test track, we applied the regenerative energy storage system in addition to the existing electric facilities. This paper present the design, manufacturing, and testing results of regenerative energy storage system.

• KEPCO Journal on Electric Power and Energy
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• v.4 no.2
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• pp.107-114
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• 2018

In recent years, ESS (Energy Storage System) has been widely used in various parts of a power system. Especially, due to its fast response time and high ramp rate, ESS is known to play an important role in regulating grid frequency and providing rotational inertia. As the number of installed and commercially operating ESSs increases, the reliability becomes an important issue. This paper introduces control schemes and presents its test method for grid-connected ESS for primary frequency regulation. The test method allows to verify the control operation in the individual operation mode and state. A validation of the method through actual ESS test in a electrical substation is presented in the case study section.

• Journal of the Earthquake Engineering Society of Korea
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• v.21 no.4
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• pp.153-161
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• 2017

Liquid storage tank is one of the major infrastructures and generally used to store gases, drinking and utilizing water, dangerous fluids, fire water and so on. According to the recent reports and experiences, the tank structures are damaged in many earthquakes due to their low energy dissipating capacity. Therefore, many researchers have been tried to know the dynamic properties of the tanks including liquids. However, vary limited experimental studies are carried out using relatively small tank models. In this study, a series of shaking table tests are performed with maximum 2 m cubic rectangular liquid storage tanks made of steel to measure the natural frequency and estimate damping coefficient of impulsive and convective mode of the tanks. Especially, the damping values under different shapes and excitation methods are estimated by logarithmic decrement method and half power band-pass method and compared with current design code and standards such as ASCE 7, Eurocode 8 and NZS. Test results show that the impulsive mode damping is around 2% which is proposed by general standards and codes but the impulsive mode damping is 0.13% average that is slightly lower than the code recommendation.

• Journal of KIISE:Computer Systems and Theory
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• v.34 no.8
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• pp.348-366
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• 2007

Capacity of modem storage devices is becoming larger than yesterday and integration of disk is increasing. It refers that physical errors can damage a lot of digital information on storage devices. So we propose file system test framework in this paper to test integrity and robustness of file systems. We develop the tool for generating bad sectors on disks and the tool which creates all physical errors defined in storage devices. We also develop the tool for immediately monitoring the condition of read and write execution on storage devices. So, by integrating those tools, we develop FORT, test framework for confirming robustness of file system. We analyze robustness of ext3 file systems by FORT. Lastly, we present draft of intelligent system merging file system and device driver's layer architecture.

• Culinary science and hospitality research
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• v.19 no.2
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• pp.167-175
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• 2013

To manufacture salad dressing with ginger, dressing with 0%, 3%, 6%, 9%, and 12% ginger added were prepared and tested for quality. The salad dressing products were evaluated for pH, acidity, chromaticity, salinity, sugar content, sensory test during storage up to 21 days at $4^{\circ}C$. The pH of the dressing increased with ginger added, whereas the acidity decreased(p<0.001). The L, a and b values increased during the storage period(p<0.01). Brix measurements decreased with ginger added, whereas the salinity increased. Also, the salinity of the dressing increased during the storage period(p<0.01). According to the sensory test results, dressing products with 9% and 12% ginger added were most preferred for the early storage days; however, the sensory test showed that the dressing with 6% ginger added was most preferred for seven test items according to storage period, indicating that the salad dressing added with 6% ginger was acceptable.