• Applied Chemistry for Engineering
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• v.10 no.6
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• pp.848-851
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• 1999

In order to increase the stability of Ginkgo Biloba extract, we investigated the effect of three different fill formulations(SBO, PEG400, and PEG600 fill types) on the stability of Ginkgo Biloba extract in three different shell formulations (ssmb, smb and gmb shell types). The stabilities of each types were evaluated by testing their disintegration time sunder the condition of $40^{\circ}C$, 75% relative humidity(RH) for 8 weeks. The formulation of Ginkgo Biloba extract with ssmb and PEG600 formulation type showed the best stability among them.

• Journal of Industrial Convergence
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• v.15 no.2
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• pp.1-6
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• 2017

This paper illustrates key features of an enterprise employment simulation which integrates a system dynamic feedback model with a cost-effectiveness optimisation capability utilising genetic algorithms. Its core is a 3-dimensional array structure tracking staff numbers by rank, by time-in-rank, by years-of-service. The resultant model, which could readily be adapted to non-Defence use, can identify, given user specification of any mix of employment rules, the likely patterns of employment behaviour including: resultant time-in-rank and years-of-service profiles; ability of a Unit to fill all positions to target strength; ability to fill promotional positions within normal rules for substantive promotion; need to fill promotional positions using rules for temporary promotion or transfer from outside; necessary recruitment pattern to sustain target strength.

• Design & Manufacturing
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• v.15 no.1
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• pp.1-7
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• 2021

The position of the gate is one of the important factors for optimal injection molding. This is because inappropriate gate positions cannot fill the cavity uniformly, which can lead to defects such as contraction. In this study, CAE was performed on hot runner injection molding of the washing machine base and plasticity was compared by changing gate position from existing gate position. A total of two alternatives have been applied to compare the plasticity of the washing machine base according to its optimal gate position. The gate position of the improved molds and the gate position of the current mold is analyzed by injection molding analysis. The results of the fill time, the pressure at V/P switchover, clamping force, and deflection were compared. In washing machine base injection molding, the deflection was reduced by about 3.76% in the improved mold 2. In improved mold 1, the fill time during injection molding was reduced by 3.32% to enable uniform charging, and the clamping force was reduced by 31.24%. We have confirmed that the position of the gate can change the charging pressure and the clamping force and affect the quality and cost savings of the molded product.

• Proceedings of the Korean Geotechical Society Conference
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• 2010.09c
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• pp.113-116
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• 2010

Ground cave-in is usually initiated by the formation of cavity within the ground due to soil loss. When the location of the cavity is deep in the ground, the detection of the cavity is not easy. Then it is possible that the hidden cavity expands for a long time to eventually cause sudden large-scale collapse. A case of large scale ground collapse in the old fill ground was studied and described in this paper. The underground cavity appeared to be caused by subsurface erosion deep in the ground and to expand/extend upward till it was ended by the catastrophic ground failure. It highlighted the importance of proper drainage work in a large scale land fill.

• Journal of Energy Engineering
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• v.22 no.4
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• pp.327-332
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• 2013

일본 연구에서는 열충격 시험을 통한 태양전지의 파괴모드에 따른 전기적 특성을 분석하였다. 시편은 Photovoltaic Module을 만들기 전 3 line Ribbon을 Tabbing한 단결정 Solar Cell을 제작하였다. 열충격 시험 Test 1의 온도조건은 저온 $-40^{\circ}C$, 고온 $85^{\circ}C$, Test 2는 저온 $-40^{\circ}C$, 고온 $120^{\circ}C$에서 Ramping Time을 포함하여 각각 15분씩, 총 30분을 1사이클로 500사이클을 각각의 조건으로 수행하였다. 열충격 시험 후 Test 1에서는 4.0%의 효율 감소율과 1.5%의 Fill Factor 감소율을 확인하였으며, Test 2에서는 24.5%의 효율 감소율과 11.8%의 Fill Factor 감소율을 확인하였다. EL(Electroluminescence)촬영 및 단면을 분석한 결과, Test 1과 Test 2 시편 모두 Cell 표면 및 내부에서의 Crack이 발견되었다. 하지만, Test 2의 시험이 Test 1보다 가혹한 온도조건의 시험으로 인해 Test 1에서 나타나지 않았던, Cell 파괴를 Test 2에서 확인하였다. 결국, Test 1에서 효율의 직접적인 감소 원인은 Cell 내부에서의 Crack이며, Test 2에서는 Cell 내부에서의 Crack 및 Cell 파괴로 인한 Cell 자체의 성능저하로 효율이 크게 감소한다는 것을 본 실험을 통하여 규명하였다.

• Journal of Drive and Control
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• v.17 no.3
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• pp.47-56
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• 2020

As a shift control of automatic transmission was managed with the electronic control unit (ECU), shift quality which is a measure of shift shock during gear change has markedly improved. However, the initial clutch pressure control of the clutch filling phase should continue to rely on the predetermined control input since the input and output speeds are unchanged until the shifting process attains the inertia phase. It is critical to minimize the clutch response time and control the clutch pressure accurately at the end of clutch fill to achieve quick shift response and smoothness. Advanced transmission companies have adopted an auto calibration method which establishes the databases for the clutch piston fill-up attributes and the frictional characteristics of the disks. In this study, a distinctive auto calibration algorithm for forklift transmission under development is proposed and verified with the real-vehicle test. The experimental calibration results showed consistent turbine dynamics at the initial stage of shifts with the properly calibrated clutch-fill control parameters. By using this technique, it is necessary to finalize the shift control for the various operation conditions.

• JSTS:Journal of Semiconductor Technology and Science
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• v.3 no.2
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• pp.69-75
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• 2003

Cell transistor and data retention time characteristics were studied in 90 nm design rule 512M-bit DRAM, for the first time. And, the characteristics of cell transistor are investigated for different STI gap-fill materials. HDP oxide with high compressive stress increases the threshold voltage of cell transistor, whereas the P-SOG oxide with small stress decreases the threshold voltage of cell transistor. Stress between silicon and gap-fill oxide material is found to be the major cause of the shift of the cell transistor threshold voltage. If high stress material is used for STI gap fill, channel-doping concentration can be reduced, so that cell junction leakage current is decreased and data retention time is increased.

• Restorative Dentistry and Endodontics
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• v.45 no.4
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• pp.42.1-42.9
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• 2020

Objective: This study aimed to examine the physical properties (pH and flow) of 2 novel bioceramic sealers. Materials and Methods: The tested sealers were a calcium hydroxide sealer (Sealapex) and 2 bioceramic sealers (BioRoot RCS and TotalFill BC Sealer). Flow measurements were conducted according to ISO 6876/2012, with a press method of 0.05 mL of sealer. The pH of fresh samples was tested immediately after manipulation, while set samples were stored for 3 times the recommended setting time. The predetermined time intervals ranged from 3 minutes to 24 hours for fresh samples and from 10 minutes to 7 days and 4 weeks for the set samples. Analysis of variance was performed, with p = 0.05 considered indicating significance. Results: The mean flow values were 26.99 mm for BioRoot, 28.19 for Sealapex, and 30.8 mm for TotalFill BC Sealer, satisfying the ISO standard. In the set samples, BioRoot RCS had higher pH values at 24 hours to 1 week after immersion in distilled water. At 2 weeks, both bioceramic sealers had similar pH values, greater than that of Sealapex. In the fresh samples, the bioceramic sealers had significantly higher initial pH values than Sealapex (p < 0.05). At 24 hours post-immersion, all sealers showed an alkaline pH, with the highest pH observed for TotalFill. Conclusions: The TotalFill BC Sealer demonstrated the highest flow. The bioceramic sealers initially presented higher alkaline activity than the polymeric calcium hydroxide sealer. However, at 3 and 4 weeks post-immersion, all sealers had similar pH values.

• Journal of The Korean Society of Agricultural Engineers
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• v.66 no.5
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• pp.41-50
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• 2024

An increasing pattern of extreme rainfall recently affected the rural infrastructures with catastrophic damage, especially the overtopping of a fill dam embankment in the Republic of Korea. The overtopping was caused by the sudden increase in reservoir water level over the dam crest level, and it was not easy work to predict a priori because of its non-linear behavior. Fuzzy time series (FTS) is a fuzzy-logic inference procedure and is suited to apply to non-linear prediction methods such as machine learning. This study used the Wangshin reservoir and Goesan-dam cases, which experienced overtopping in 2023 and 2022, respectively. Wangshin Reservoir was a typical agricultural fill dam and needed to stack more available data, with only the daily storage rate (water level) of 7 years, starting on 2 May 2016. Therefore, we used Goesan-dam data to select appropriate variables and compare the analysis result, which was stacked with about 17 years of records. The analyses adapted LSTM to compare with FTS. As a result, the reservoir water level was applied to predict the overtopping water level, and it was shown that the FTS method could predict the actual water levels effectively according to the result of comparison with LSTM. Then, the FTS method was expected to predict reservoir water level a priori to make appropriate countermeasures on overtopping events as one of the alternatives.

• Journal of the Korean GEO-environmental Society
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• v.10 no.7
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• pp.67-79
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• 2009

Although readjustment of monitoring system for existing fill dam maintenance is needed by the sustainable increasing of the abandonment rate of monitoring devices by malfunction through the life-cycle of dam, monitoring plans for long-term dam safety has relied on the experience and the opinion of minor expert group without systematic and quantitative analysis on the failure modes and the priority order of monitoring devices on maintenance. In this study the priority order of monitoring devices of existing 5 fill dams was evaluated quantitatively based on the preceding study (Andersen et al, 1999) and the result recommended the establishment of real-time monitoring system for seepage, pore pressure and crest settlement as the readjustment plan for existing fill dam monitoring system. This readjustment plan matches well with the recommendation of PWRI (1984), JCOLD (1986) and the results from Bagherzadeh-Khakkahali and Mirghasemi (2005).