• 한국생물공학회:학술대회논문집
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• 2003.10a
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• pp.329-333
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• 2003

Human granulocyte-macrophage colony-stimulating factor (hGM-CSF) is a glycoprotein that stimulates the production of granulocytes, macrophages and white blood cells. hGM-CSF secreted by transgenic Nicotiana tabacum suspension cells was unstable in the culture medium and rapidly degraded by extracellular preteases. In order to reduce extracellular pretense activity, culture temperature was lowered. Then, the production of hGM-CSF by transgenic plant suspension cell cultures could be enhanced by reduced degradation of hGM-CSF at low temperature.

• Proceedings of the Korean Society for Agricultural Machinery Conference
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• 2000.11b
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• pp.498-505
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• 2000

Performance of a hydraulic system is influenced by its working temperature. Therefore, it is very important to make the system perform uniformly in an entire range of the working temperature. In this study a simulation of a hydraulic control system for the powershift transmission of tractors was conducted and the effect of the temperature was investigated in terms of design conditions of the system. Results of the simulation are as follows. The hydraulic control system with a spring accumulator was found to be more convenient to control the shifting time than that with a gas accumulator. By returning the oil from the clutches to the system through a path between the filter and pump, the time delay due to the pressure difference between the low and high temperatures could be reduced. Therefore, it was recommended that the hydraulic control system for the powershift transmission of tractors must be equipped with a spring accumulator and a circuit to return oil from the clutches to the system through a path between the filter and pump.

• Environmental Engineering Research
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• v.11 no.3
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• pp.149-155
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• 2006

NOx reduction experiments were conducted by direct injection of urea into a diesel fueled, combustion-driven flow reactor which simulated a single engine cylinder ($966cm^3$). NOx reduction tests were carried out over a wide range of air/fuel ratios (A/F=20-40) using an initial NOx level of 530ppm, and for normalized stoichiometric ratios of reductant to NOx (NSR) of 1.5 to 4.0. The results show that effective NOx reduction with urea occurred over an injection temperature range of 1100 to 1350K. NOx reduction increased with increasing NSR values, and about a 40%-60% reduction of NOx was achieved with NSR=1.5-4.0. Most of the NOx reduction occurred within the cylinder and head section (residence time <40msec), since temperatures in the exhaust pipe were too low for additional NOx reduction. Relatively low NOx reduction is believed to be due to the existence of higher levels of CO and unburned hydrocarbons (UHC)inside the cylinder, and large temperature drops along the reactor. Injection of secondary combustible additives (diesel fuel/$C_2H_6$) into the exhaust pipe promoted further substantial NOx reduction (5%-30%) without shifting the temperature windows. Diesel fuel was found to enhance NOx reduction more than $C_2H_6$, and finally practical implications are further discussed.

• Fashion & Textile Research Journal
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• v.24 no.6
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• pp.775-781
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• 2022

As part of research to develop a permanent wave-reducing agent for hair, in the current study, 0.1%-1.0% of Polyquaternium-10 was added to a permanent reagent containing Nicotinoyl Dipeptide-23 to prepare the agent, which was tested on damaged hair. The pH change was relatively stable even after a date, but due to the hair's natural composition, 0.1%-0.6% of the Polyquaternium-10 concentration according to pH was suitable. The temperature safety experiment demonstrated it to be stable at a high temperature and at room temperature, but when a Polyquaternium-10 concentration of 0.9% or higher was added at 0℃, coagulation occurred. In terms of the force efficiency of permanent wave formation, wave efficiency lowered as the concentration increased: the longer the wave lasts, the lower the Polyquaternium-10 concentration. The permanent moisture content was found to be higher as the concentration of Polyquaternium-10 increased. Therefore, when Polyquaternium-10 is applied to the permanent wave-reducing agent, considering stability, permanent formation, durability, and moisture rate, the most suitable concentration was found to be that of Polyquaternium-10 in the cysteine-reducing agent. A novel finding from this study is that as the concentration of Polyquaternium-10 increases, the consistency of the permanent wave-reducing agent changes, shifting from a liquid to a viscous liquid formulation.

• The Korean Journal of Malacology
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• v.28 no.3
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• pp.277-291
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• 2012

Aquaculture is challenged by a number of constraints with future efforts towards sustainable production. Global climate change has a potential damage to the sustainability by changing environmental surroundings unfavorably. The damaging parameters identified are water temperature, sea level, surface physical energy, precipitation, solar radiation, ocean acidification, and so on. Of them, temperature, mostly temperature elevation, occupies significant concern among marine ecologists and aquaculturists. Ocean acidification particularly draws shellfish aquaculturists' attention as it alters the marine chemistry, shifting the equilibrium towards more dissolved CO2 and hydrogen ions ($H^+$) and thus influencing signaling pathways on shell formation, immune system, and other biological processes. Temperature elevation by climate change is of double-sidedness: it can be an opportunistic parameter besides being a generally known damaging parameter in aquaculture. It can provide better environments for faster and longer growth for aquaculture species. It is also somehow advantageous for alleviation of aquaculture expansion pressure in a given location by opening a gate for new species and aquaculture zone expansion northward in the northern hemisphere, otherwise unavailable due to temperature limit. But in the science of climate change, the ways of influence on aquaculture are complex and ambiguous, and hence are still hard to identify and quantify. At the same time considerable parts of our knowledge on climate change effects on aquaculture are from the estimates from data of fisheries and agriculture. The consequences may be different from what they really are, particularly in the temperature region. In reality, bivalves and tunicates hung or caged in the longline system are often exposed to temperatures higher than those they encounter in nature, locally driving the farmed shellfish into an upper tolerable temperature extreme. We review recent climate change and following environment changes which can be factors or potential factors affecting shellfish aquaculture production in the temperate region.

• Proceedings of the Korean Society of Propulsion Engineers Conference
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• 2007.11a
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• pp.105-109
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• 2007

Three methods of nozzle flow analysis, frozen-equilibrium, shifting-equilibrium and non-equilibrium approaches, were used to rocket nozzle flow, those were coupled with the methods of computational fluid dynamics code. For a design of high temperature rocket nozzle, chemical equilibrium analysis which shares the same numerical characteristics with frozen flow analysis can be an efficient design tool for predicting maximum thermodynamic performance of the nozzle. In this study, shifting-equilibrium flow analysis was carried out for the 30 $ton_f$-class KARl liquid rocket engine nozzle together with frozen flow. The performance evaluation based on the 30 $ton_f$-class KARl LRE nozzle flow analyses will provide an understanding of the thermochemical process in the nozzle and performances of nozzle.

• Journal of the Korean Society for Nondestructive Testing
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• v.30 no.5
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• pp.423-428
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• 2010

In this paper, we analyzed the characteristics of thermal deformation of the TPS which is a core part of engine in vehicle by measuring out-of-plane deformation using ESP!. Inspection area of a test piece was minimized to 5 cm by 5 cm by using a high resolution CCD and a zoom lens. 4-step phase shifting method was used along with phase unwrapping algorithm to get a continuous phase map, configurations and deformations were displayed as 3D images. When heating the test pieces while maintaining the temperature at about $70^{\circ}C$, the out-of-plane deformations were measured. The results showed that a test piece with longer distance traveled tends to show larger thermal deformation, we could observes a convex shaped deformation on the surface. The inner defect sample, we could monitor discontinuous pattern phase map, and a concave shaped deformation on the surface.

• Proceedings of the Korean Society of Propulsion Engineers Conference
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• 2008.03a
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• pp.448-451
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• 2008

Three methods of nozzle flow analysis, frozen-equilibrium, shifting-equilibrium and non-equilibrium approaches, were used to rocket nozzle flow, those were coupled with the methods of computational fluid dynamics code. For a design of high temperature rocket nozzle, chemical equilibrium analysis which shares the same numerical characteristics with frozen flow analysis can be an efficient design tool for predicting maximum thermodynamic performance of the nozzle. Frozen fluid analysis presents the minimum performance of the nozzle because of no consideration for the energy recovery. On the other hand, the case of chemical-equilibrium analysis is able to forecast the maximum performance of the nozzle due to consideration for the energy recovery that is produced for the fast reaction velocity compared with velocity of moving fluid. In this study, using the chemical equilibrium flow analysis code that is combined the modified frozen-equilibrium and the chemical-equilibrium. In order to understand the thermochemical characteristic components and the accompanying energy recovery, shifting-equilibrium flow analysis was carried out for the 30 $ton_f$-class KARI liquid rocket engine nozzle together with frozen flow. The performance evaluation based on the 30 $ton_f$-class KARI LRE nozzle flow analyses will provide an understanding of the thermochemical process in the nozzle and performances of nozzle.

• Journal of The Korean Society of Agricultural Engineers
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• v.64 no.6
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• pp.35-41
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• 2022

Heavy snow damage can be prevented in advance with an appropriate security system. To develop the security system, we developed a model that predicts snow depth after a few hours when the snow depth is observed, and utilized it to calculate a failure probability with various types of greenhouses and observed snow depth data. We compared the Markov chain model and Bayesian long short-term memory models with varying input data. Markov chain model showed the worst performance, and the models that used only past snow depth data outperformed the models that used other weather data with snow depth (temperature, humidity, wind speed). Also, the models that utilized 1-hour past data outperformed the models that utilized 3-hour data and 6-hour data. Finally, the Bayesian LSTM model that uses 1-hour snow depth data was selected to predict snow depth. We compared the selected model and the shifting method, which uses present data as future data without prediction, and the model outperformed the shifting method when predicting data after 11-24 hours.

• Food Science of Animal Resources
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• v.33 no.4
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• pp.474-480
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• 2013

This study was performed to investigate the effects of high pressure/high temperature (HPHT) treatment on the recovery efficiency and characteristics of porcine placenta hydrolysates. The placenta hydrolysates were characterized by solubility, free amino acid contents, gel electrophoresis, gel permeation chromatography (GPC) and amino acid composition. Placenta was treated at 37.5 MPa of pressure combined with various temperatures (150, 170, and $200^{\circ}C$) or various holding times (0, 30, and 60 min at $170^{\circ}C$). Insoluble raw placenta collagen was partially solubilized (> 60% solubility) by the HPHT treatment. Free amino group content of placenta collagen was increased from 0.1 mM/g collagen to > 0.3 mM/g collagen after HPHT treatment, reflecting partial hydrolysis of collagen. The molecular weight ($M_w$) distribution showed evidence of collagen hydrolysis by shifting of $M_w$ peaks toward low molecular weight when treated temperature or holding time was increased. Alanine (Ala), glycine (Gly), hydroxyproline (Hyp), and proline (Pro) contents increased after the HPHT treatments compared to a decrease in the others. In particular, the increase in Gly was obvious, followed by Hyp and Pro, reflecting that placenta hydrolysates were mainly composed of these amino acids. However, increasing temperature or holding time hardly affected the amino acid compositions. These results indicate that the HPHT treatment is advantageous to hydrolyze collagen derived from animal by-products.