• Asian-Australasian Journal of Animal Sciences
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• v.32 no.6
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• pp.783-791
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• 2019

Objective: This study was to evaluate the fermentation dynamics, structural and nonstructural carbohydrate composition and in vitro gas production of rice straw ensiled with lactic acid bacteria and molasses. Methods: Fresh rice straw was ensiled in 1-L laboratory silos with no additive control (C), Lactobacillus plantarum (L), molasses (M) and molasses+Lactobacillus plantarum (ML) for 6, 15, 30, and 60 days. After storage, the silages were subjected to microbial and chemical analyses as well as the further in vitro fermentation trial. Results: All additives increased lactic acid concentration, and reduced pH, dry matter (DM) loss and structural carbohydrate content relative to the control (p<0.05). The highest organic acid and residual sugar contents and lignocellulose reduction were observed in ML silage. L silage had the highest V-score with 88.10 followed by ML silage. L and ML silage improved in vitro DM digestibility as compared with other treatments, while in vitro neutral detergent fibre degradability (IVNDFD) was increased in M and ML silage (p<0.05). M silage significantly (p<0.05) increased propionic acid (PA) content and decreased butyric acid content and acetic acid/PA as well as 72-h cumulative gas production. Conclusion: The application of ML was effective for improving both the fermentation quality and in vitro digestibility of rice straw silage. Inclusion with molasses to rice straw could reduce in vitro ruminal gas production.

• Journal of Nuclear Fuel Cycle and Waste Technology(JNFCWT)
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• v.15 no.4
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• pp.403-409
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• 2017

For dry storage of the spent nuclear fuel (SNF) stored in the storage pool of a nuclear power plant, essentially all moisture must be removed to prevent corrosion of the assembly and canister internals and/or degradation of fuel cladding integrity after SNF canister loading operation. R&D work is now in progress on a forced gas drying system that can be used to remove residual water in canisters. In this work, preliminary design is performed to manufacture the forced gas drying system. This process includes a case study of dry methods for canister moisture removal, relative codes and standards, confirmation of adequate dryness, needs analysis at plant sites, and characteristics of SNF stored in pools. Through this preliminary design work, we obtained a conceptual flow diagram and preliminary P&ID of the forced gas drying system. The results of this study can be used to determine details of the design to manufacture the forced gas drying system.

• 한국연소학회:학술대회논문집
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• 2014.11a
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• pp.285-288
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• 2014

Experiments have been performed for the burners used in the non-oxidizing direct fired furnaces for the cold rolled plate to investigate the effect of fuel/air mixing patterns of the burner nozzle on flame shape, temperature and combustion gas concentration. CFD simulation has also been performed to investigate the mixing state of air-fuel for a nozzle mixing burner and a partially pre-mixing burner. A partially pre-mixing burner showed that flame temperature increased up to $26^{\circ}C$ on average compared than that of the nozzle mixing. It also showed that the mixing distance is important at the partially pre-mixing burner. Test results for a partially pre-mixing burner showed that the residual oxygen concentration and the volume ratio of $CO/CO_2$ of the flame were applicable to be used in field furnaces.

• Proceedings of the Korean Vacuum Society Conference
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• 2015.08a
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• pp.103.1-103.1
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• 2015

위성체 개발에 있어서 지상에서 위성체의 부품에 대한 고온($85^{\circ}C$ 이상)과 고진공($5.0{\times}10-3Pa$ 이하)의 상태를 모사하여 오염물질을 제거하는 베이크아웃 시험이 필수적이다. 일반적으로 베이크아웃 시험의 종료여부는 TQCM (Thermoelectric Quartz Crystal Microbalance)을 이용한 탈기체(outgassing)의 흡착률을 측정하여 결정한다. 측정된 흡착률을 통해 시험 대상 표면에서 발생하는 탈기체량을 추정할 수 있으며, 결국 시험 대상의 우주 부품으로써의 적합성을 판단할 수 있다. TQCM을 적용하지 못하는 경우, 베이크아웃 시험 종료여부를 판단하기 위해 잔류가스분석기(Residual Gas Analyzer: RGA)를 활용하는 것을 고려하였다. 베이크아웃 시험 중 잔류가스분석기를 활용하여 시편에서 방출되는 오염물질을 측정하였으며, 그 중 측정량이 가장 많은 40-45 amu 범위의 측정값 추이를 관찰하여, 베이크아웃 시험 종료조건 수립 가능성을 검토하였다.

• Proceedings of the KSME Conference
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• 2001.06d
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• pp.331-336
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• 2001

Theoretical approach was taken to the whole CNG refueling process. In particular, this study was focused on the prediction of flow rate at any given piping configuration of CNG system, in order that a simulation program for the CNG refueling system should be developed. The simulation result of refueling process was compared with experimental result obtained from various kinds of fueling configuration. The simulation results showed a satisfactory agreement within 10% errors in fueling time, fueling amount, and residual pressure. The developed program would be used a good engineering tools for estimating fueling performance for a any given CNG station.

• Journal of Sensor Science and Technology
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• v.22 no.3
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• pp.175-180
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• 2013

This paper describes the characteristics of cubic silicon carbide (3C-SiC) films grown on a carbonized Si(100) substrate, using hexamethyldisilane (HMDS, $Si_2(CH_3)_6$) as a safe organosilane single precursor in a nonflammable $H_2$/Ar ($H_2$ in Ar) mixture carrier gas by atmospheric pressure chemical vapor deposition (APCVD) at $1280^{\circ}C$. The growth process was performed under various conditions to determine the optimized growth and carbonization condition. Under the optimized condition, grown film has a single crystalline 3C-SiC with well crystallinity, small voids, low residual stress, low carrier concentration, and low RMS. Therefore, the 3C-SiC film on the carbonized Si (100) substrate is suitable to power device and MEMS fields.

• Journal of Powder Materials
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• v.19 no.5
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• pp.356-361
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• 2012

The ultra-fine and less agglomerated titanium carbonitride particles were successfully synthesized by magnesiothermic reduction with low feeding rate of $TiCl_4+1/4C_2Cl_4$ solution. The sub-stoichiometric titanium carbide ($TiC_{0.5{\sim}0.6}$) particles were produced by reduction of chlorine component by liquid magnesium at $800^{\circ}C$ of gaseous $TiCl_4+1/4C_2Cl_4$ and the heat treatments in vacuum were performed for 5 hours to remove the residual magnesium and magnesium chloride mixed with produced $TiC_{{\sim}0.5}$. The final $TiC_{{\sim}0.5}N_{0{\sim}0.5}$ particle with near 100 nm in mean size and high specific surface area of $65m^2/g$ was obtained by nitrification under nitrogen gas at $1,150^{\circ}C$ for 2 hrs.

• Journal of Powder Materials
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• v.8 no.2
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• pp.117-123
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• 2001

Formation of pores in melt-processed $YBa_2Cu_3O_{7-x}$ (123) oxides and its effect on the microstructure were studied. Spherical pores with a size of a few tens of microns were formed due to the evolution of oxygen gas during melting of a 123 oxide. Some of pores were converted into liquid pockets by liquid filling, but others remained unfilled. The liquid pockets were converted into spherical 123 regions with a lower $Y_2BaCuO_5$ (211)density through the peritectic reaction during subsequent cooling, while the pores were entrapped into the periteictically grown 123 grains. The spherical 123 regions often consists of a residual melt due to the unbalanced peritectically reaction.

• Journal of Korea Foundry Society
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• v.32 no.3
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• pp.133-137
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• 2012

Chill vent has a zigzag venting path which allows residual air or gases to exhaust out very quickly from the die cavity. However molten metal sometimes comes out through the gas venting surfaces causing flash. Effect of designing factors of chill vent and processing variables in high pressure die casting on the performance of chill vent was investigated through a series of calculations by using a commercial code. The most influential factor was the thickness of chill vent, followed by inlet velocity, vent width and die temperature.

• Journal of the Korean Society of Combustion
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• v.15 no.3
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• pp.25-31
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• 2010

Combined technique of burner and DOC has been used for regeneration of Diesel Particulate Filter. Experiments has been performed to increase the temperature of engine exhaust gas to burn the collected soot in DPF at all conditions of operation of 3 liter diesel engine. Ignition temperature of soot can be successfully obtained by heats of burner flame and residual fuel oxidation at diesel oxidation catalyst even in the condition of oxygen deficiency. It is found that the load of air compressor and heat loss can be reduced to the level of practical application. It is also found that CO and THC emissions are not increase by additional combustion of regeneration burner.