• Journal of the Korean Society for Aviation and Aeronautics
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• v.30 no.2
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• pp.24-33
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• 2022

This study analyzed and derived a plan to reduce fuel consumption of domestic aircraft. Specifically, this study tested fuel consumption in the short-distance flights of B737. Fuel consumption was calculated by substituting the simulation variable values into Matlab. The strength of this study is that the actual operating environment was reflected by collecting the B737 flight data. As a result of the study, the domestic fuel consumption rate in the computed flight plan was less than the current fuel consumption rate. Existing limitations of this study is that it was difficult to reflect the various variables constituting the flight environment, and thus there can be errors in the measurement of the fuel consumption. There are two major expected applications from this study. First, applying the plans from this study will lead to a reduction in the amount of fuel and thus provide positive economic effects for commercial airlines. Second, the plan from this study will provide a basis for pilots to predict fuel consumption more accurately. In conclusion, this study proposes a fuel saving plan with useful applications for pilots and airlines.

• Journal of Climate Change Research
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• v.5 no.1
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• pp.61-70
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• 2014

The amount of greenhouse gas (GHG) emissions has been increasing steadily over the last 3 years (2009~2011), averaging 5.7 percent a year, due to the growth of low cost carriers and the increased demand for air transportations. The present study attempts to investigate the aviation fuel consumption and GHG emissions of Tier 3a type by the flight phase from three aircraft type such as B737-600(routes between Gimpo-Jeju airport), B737-700(routes between Gimpo-Jeju airport and Inchon-Narita), B737-800(routes between Inchon-Narita) using the Flight Operation Quality Assurance(FOQA) data of the year 2011.

• Microbiology and Biotechnology Letters
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• v.50 no.3
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• pp.319-327
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• 2022

γ-Aminobutyric acid (GABA) is a multi-functional compound with broad applications for food industry. GABA producing bacteria were isolated from cabbage kimchi. Among them, B737 was the best GABA producer when culture supernatants were analyzed by TLC. B737 was identified as Levilactobacillus brevis by 16S rRNA gene sequencing. Its glutamate decarboxylase (GAD) gene was cloned by PCR and the nucleotide sequence determined. B737 GAD consisting of 485 amino acids is the largest in size among GADs reported from LAB so far. gadB from L. brevis B737 was overexpressed in Escherichia. coli BL21(DE3) using pET26b(+).pET26b(+). The recombinant GAD was purified and its size was 55 kDa by SDS-PAGE. Maximum GAD activity was observed at pH 5 and 40℃ and the activity was dependent on pyridoxal 5'-phosphate. K_m and V_max of recombinant GAD were 6.2 ± 0.06 mM and 0.34 ± 0.002 mM/min, respectively. L. brevis B737 can be used as a starter for fermented foods with high GABA contents.

• Journal of the Korean Society for Aviation and Aeronautics
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• v.28 no.1
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• pp.106-114
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• 2020

The Lion Air JT610 accident in Indonesia in October 2018, along with the Ethiopian Airline ET302 accident in March 2019, is an significant aircraft accident that detects defects of the B737MAX aircraft. Shortly after the accident, the FAA prohibited operation of the aircraft. This action has affected the market environment of airlines and aircraft manufacturers around the world. In October 2019, Indonesian Traffic Safety Committee released an accident investigation report for Lion Air JT610, which concluded that the causes of the accident were MCAS design defects, lack of education and training, and errors in the repair process. This paper summarizes the flight control system of the B737MAX aircraft, the causes of the accident based on the final accident investigation report, and provides considerations for aircraft design and retrofit.

• Kyungpook Mathematical Journal
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• v.56 no.3
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• pp.737-743
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• 2016

Let a and b be two ideals of a commutative Noetherian ring R, M a finitely generated R-module and i an integer. In this paper we study formal local cohomology modules with respect to a pair of ideals. We denote the i-th a-formal local cohomology module M with respect to b by ${\mathfrak{F}}^i_{a,b}(M)$. We show that if ${\mathfrak{F}}^i_{a,b}(M)$ is artinian, then $a{\subseteq}{\sqrt{(0:{\mathfrak{F}}^i_{a,b}(M))$. Also, we show that ${\mathfrak{F}}^{\text{dim }M}_{a,b}(M)$ is artinian and we determine the set $Att_R\;{\mathfrak{F}}^{\text{dim }M}_{a,b}(M)$.

• Annals of Surgical Treatment and Research
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• v.95 no.5
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• pp.240-248
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• 2018

Purpose: This study aimed to validate the synergistic effect of ABT-737 on docetaxel using MDA-MB-231, a triple negative breast cancer (TNBC) cell line overexpressing B-cell lymphoma-2 (Bcl-2). Methods: Western blot analysis was performed to assess expression levels of Bcl-2 family proteins and caspase-related molecules. Cell viability was assessed by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay. Cell cycle distribution was determined by flow cytometry analysis. Benzyloxycarbonyl-Val-Ala-Asp(OMe)-fluoromethylketone (z-VAD-fmk) was used for pretreatment to assess the role of caspases. Results: Cell viability of MDA-MB-231 after combination treatment with ABT-737 and docetaxel was significantly lower than that after docetaxel or ABT-737 monotherapy based on MTT assay (both P < 0.001), with a combination index of 0.41. The proportion of sub-G1 population after combination treatment was significantly higher than that after docetaxel or ABT-737 monotherapy (P = 0.001, P = 0.003, respectively). Pretreatment with z-VAD-fmk completely restored cell viability of MDA-MB-231 from apoptotic cell death induced by combination therapy (P = 0.001). Although pro-caspase-8 or Bid did not show significant change in expression level, pro-casepase-9 showed significantly decreased expression after combination treatment. Cleaved caspase-3 showed increased expression while poly (ADP-ribose) polymerase cleavage was induced after combination treatment. However, hypoxia-inducible factor 1-alpha and aldehyde dehydrogenase 1 totally lost their expression after combination treatment. Conclusion: Combination of ABT-737 with docetaxel elicits synergistic therapeutic effect on MDA-MB-231, a TNBC cell line overexpressing Bcl-2, mainly by activating the intrinsic pathway of apoptosis. Therefore, adjunct of ABT-737 to docetaxel might be a new therapeutic option to overcome docetaxel resistance of TNBCs overexpressing Bcl-2.

• Proceedings of the Korean Powder Metallurgy Institute Conference
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• 2006.09a
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• pp.555-556
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• 2006

The study examines hardness pattern of SH737-2Cu-.9C samples transient liquid phase sintered at different temperatures viz. $1120^{\circ}C$, $1180^{\circ}C$ and $1250^{\circ}C$, heat treated by various methods and then tempered at different temperatures. Sintered samples were characterized for density and densification parameter, and austenitized at $900^{\circ}C$, subsequently cooled by four different methods viz. annealing, normalizing, oil and brine quenching. Hardness pattern was found minimum for air cooled and maximum for brine quenched, and samples sintered at $1250^{\circ}C$ had relatively higher hardness. The O.Q and B.Q samples were then tempered at $200^{\circ}C$, $400^{\circ}C$, $600^{\circ}C$ and $700^{\circ}C$. Hardness pattern typically showed secondary hardness taking place, with maximum around $600^{\circ}C$.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2012.05a
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• pp.737-738
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• 2012

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2008.06a
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• pp.737-738
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• 2008

• Transactions of the Korean Society of Mechanical Engineers B
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• v.33 no.10
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• pp.737-747
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• 2009

This study is to investigate the effect of the moisture, volatile matter and particle size in the coal on the pulverized coal combustion characteristics using CFD. The results show that as the moisture content in coal increases, flame temperature decreases because of heat loss driven from latent heat of vaporization and reduction of heating value. As the volatile matter content in the coal increases, the temperature in the region near the burner increases, while the temperature in rear region of boiler decreases. The solution to keep the temperature in the rear region of boiler is suggested that particle size is needed to be larger. As the particle size increases, the temperature in the rear region of boiler show tendency to increase, for combustion burning time of coal could be extended.