• Proceedings of the Korean Society of Propulsion Engineers Conference
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• 2010.05a
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• pp.29-33
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• 2010

This study aim to investigate the internal flow characteristics by recess length of swirl coaxial injector for gas generator has propellant of Kerosene-LOx. Recess length is a very important element, have influence in spray stability and LOx post damage. The influence of recess length was analyzed by visualizing internal flow and measuring liquid film thickness and manifold pressures. Also, each spray characteristic by recess length was investigated in internal or external injector.

• Proceedings of the Korean Society of Propulsion Engineers Conference
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• 2008.03a
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• pp.849-854
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• 2008

We have been developing a 1500N-thrust Swirling-Oxidizer-Flow-Type hybrid rocket engine. In order to put the engine into practical use, we conducted long duration burning experiments up to 25s to examine the influence of configuration change of fuel grain on the engine performance and designed an LOX vaporization nozzle to supply GOX for the 1500N-thrust engine. The experiment with a small hybrid rocket engine showed that combustion was stable and the engine performance was approximately constant during combustion. There was no essential problem to with increasing combustion time. The LOX vaporization nozzle designed had 30 rectangular channels with a depth of 0.5mm. During passing through the nozzle, the LOX increased in temperature and vaporized sufficiently.

• Proceedings of the Korean Society of Propulsion Engineers Conference
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• 2011.04a
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• pp.12-15
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• 2011

The most widely used kerosene-LOx liquid-propellant rocket engines in these days have a similar engine schematic to those of the past because of the development cost and the reliability. The efficiency of engines could be increased by the factors such as a cooling method, engine cycles, shape of cooling channels, additional coolant and so on. In this article, it is described that some design ideas for performance enhancement by exchange kerosene with LOx of a coolant.

• Laboraroty Animal Research
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• v.34 no.4
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• pp.147-159
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• 2018

Genetically engineered mouse models are commonly preferred for studying the human disease due to genetic and pathophysiological similarities between mice and humans. In particular, Cre-loxP system is widely used as an integral experimental tool for generating the conditional. This system has enabled researchers to investigate genes of interest in a tissue/cell (spatial control) and/or time (temporal control) specific manner. A various tissue-specific Cre-driver mouse lines have been generated to date, and new Cre lines are still being developed. This review provides a brief overview of Cre-loxP system and a few commonly used promoters for expression of tissue-specific Cre recombinase. Also, we finally introduce some available links to the Web sites that provides detailed information about Cre mouse lines including their characterization.

• Proceedings of the Korean Society of Propulsion Engineers Conference
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• 2010.11a
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• pp.72-76
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• 2010

To research and develop a high performance injector for LRE, it needs not only cold flow test, but also investigations of combustion performance, optimization of cyclogram and thermo-fluid dynamical characteristics of combustion flow field through hot-fire test. In this study, hot-fire test of LOX-CH4 coaxial swirl injector has been carried out using lab-scale hot fire test stand which can supply and control cryogenic propellant. Ignition and continuous combustion for LOX-$GCH_4$ propellant of 0.19 kg/s total mass flowrate and 2.80 O/F Ratio was achieved through cyclogram optimization. The mean combustion chamber pressure and thrust were measured as approximately 1.43 MPa and 38.7 kgf respectively.

• Journal of agriculture & life science
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• v.46 no.5
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• pp.111-125
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• 2012

In order to evaluate suitability by processing for non-GM soybean cultivars such as Gaechuck#2, Jinyangkong and CJ#1 lacking lipoxygenase (LOX) and kunitz trypsin inhibitor (KTI) protein, physicochemical characteristics and antioxidant activity of Kanjang made from above soybean were compared to Kanjang made from a conventional cultivar (Taekwangkong). Proximate compositions of soybeans were similar for the 4 kinds cultivars. Total phenol and flavonoid contents were significantly higher in cultivars lacking LOX and KTI protein than the Taekwangkong. In Kanjang, contents of total and reducing sugar were higher in Taekwangkong Kanjang than Kanjang from made cultivars lacking LOX and KTI protein. Contents of total and amino type nitrogen were the highest in the Jinyangkong Kanjang. Mineral contents were higher in the Jinyangkong and CJ#1 Kanjangs, amino acid contents were higher in the Kanjang made from 3 cultivars lacking LOX and KTI protein than the Taekwangkong. Taste of the Jinyangkong Kanjang with higher sweety and savory was also found to be superior to that of others in overall acceptability evaluation. Total phenol and flavonoid contents in Kanjang were significantly higher in the Kanjang made from cultivars lacking LOX and KTI protein than the Taekwangkong. Radical scavenging activity of Kanjang was increased in the total phenol contents dependent on. Reducing power by ferric-reducing antioxidant potential (FRAP) was significantly higher the Kanjang made from Gaechuck#2 and CJ#1 than the Taekwangkong. $Fe^{2+}$ chelating activity was higher in Taekwangkong Kanjang than the other cultivars, but its activity was similar to Jinyangkong Kanjang. Therefore, higher nutritional composition, total phenol and flavonoids contents and antioxidant activity in the Kanjang made from soybean cultivars lacking LOX and KTI protein might be provide better benefit for manufacture of another their products.

• Proceedings of the Korean Society of Propulsion Engineers Conference
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• v.y2005m4
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• pp.151-154
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• 2005

A study was conducted to investigate safe testing on propulsion system, especially concentrated on effects of contaminants accumulation and transfer in LOX system. Several methods for system operation decreasing accidents caused by oxidizer leakage and contaminants accumulation was investigated. These methods can be applied to LOX system and other propellants system in liquid propellants propulsion system.

• Proceedings of the KSME Conference
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• 2004.11a
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• pp.419-424
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• 2004

we performed the underwater explosion analysis for the liquefied oxygen tank - a kind of fuel tank of a mid-size submarine, and tried to verify the structural safety for this structure. First, we reviewed the theory and application of underwater explosion analysis using Structure-Fluid Interaction technique and its finite element modeling scheme. Next, we modeled the explosive and sea water as fluid elements, the LOX tank as structural elements and the interface between two regions as ALE scheme. The effect on shock pressure and impulse of fluid mesh size and shape are also investigated. As the analysis result, the shock pressure due explosion propagated into the water region and hit the structure region. The plastic deformation and the equivalent stress highly appeared at the web frame and the shock mount of LOX structure, but these values were acceptable for design criteria.

• Proceedings of the Korean Society of Propulsion Engineers Conference
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• 2003.10a
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• pp.238-241
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• 2003

In case of liquid rocket using turbopump, the inner pressure of liquid oxygen tank is maintained low, so vaporization of LOX is generally occurred. This vaporization tendency increases as the inlet helium gas temperature is higher. For estimating the amount of helium in the rocket system, the LOX vaporization phenomena should be carefully considered. In this paper, Inner process of LOX tank is analyzed by two phase flow modeling. the vaporization rate and required Helium mass is investigated with varying inlet helium temperature and heat transfer coefficient.

• Proceedings of the Korean Society of Propulsion Engineers Conference
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• 2006.11a
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• pp.207-210
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• 2006

Injector is one of the most important elements in Liquid rocket Engine design, and how to arrange these injectors on the head determines the engine performance. In this study, when the swirl injectors are used for the 1st designing of injector head of 170 tonf UDMH-LOX as the propellant of LRE, a distribution relation of the mass flow rate per unit area was calculated from the function of ${\Phi}$, which is related with the mass flow rate characteristics of swirl injector. And the combustion characteristics by circumferential axis were estimated using this relation under the consideration of combustion core and film cooling area.