• Journal of Biomedical Engineering Research
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• v.16 no.1
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• pp.9-16
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• 1995

Biodegradable poly (I ,4-butanediol succinate) (PBS) was synthesized from 1,4-butanediol and succinic anhydride. The glass transition temperature of poly (I, 4-butanediol succinate) was revealed at $73^{\circ}C$. The crystallization and cold crystallization of the polymers were investigated as a function of holding time in melt state, cooling rate. reheating, and molecular weight. Chain scission and/or cmsslinking did not occur in the melt state at var.ious holding times. Slower scanning rate can allow more times for nucleation, rearrangement, and packing of the polymer chain, so the onset temperature of crystallization from the melt was increased. PBS crystallized from the melt was found to have spherulitic structure. The degradation behavior of PBS was studied under basic conditions and with microorganisms using the modified ASTM method. In the basic solution. PBS lost up to 85% of its mass within two days. Based upon visual observation, the crystalline structure of films composed of larger molecular weight polymers retained their crystallinity longer than similar structures in low molecular weight samples.

• Korean journal of food and cookery science
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• v.6 no.2
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• pp.27-36
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• 1990

Injeolmi is a kind of rice cake made from glutionusrice grains by steaming and pounding much into dough. The way of making Injeolmis has an important effect on the characteristics of Injeolmis; whether the glutinous rice is Japonica or Japonica/Indica, and whether it is steamed in rice grain, or in rice powder. The characteristics of Injeolmi were investigated through sensory evaluation and Instron Universal testing machine. The results were as follows; 1. Injeolmi which was steamed in glutinous rice was more chewier than powder Injeolmi after 48 hours. 2. In the case of changing ${\beta}$-starch to ${\alpha}$-starch by reheating. Injeolmi with microwave oven, the result was same as above investigation in color, appearance, and chewiness. But in hardness grain Injeolmi became tenderer. 3. Instron measurement of texture indicated that there were significant differences in hardness. This result was the same as that by the sensory evaluation. 4. The preference for Injeolmi was increased when it was made of high moisture contented glutinous rice. japonica had more moisture than J/Indica.

• Korean journal of food and cookery science
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• v.12 no.2
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• pp.129-137
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• 1996

The purpose of this study was that to estimate the microbial and sensory quality by the method and time of holding in the step of holding of Cow's Knee Broth, Stir-Fry Pork and Cooked Cuttlefish that were provide at the industry foodservice establishment, then to suggest safer feeding by the reasonable holding method. The results are as follows: Cow's Knee Broth: holding at room temperature was shown that the number of mi- crobiology by passage of the holding time was higer than the case of holding at steam table, but it was lower after reheating it. As a result of sensory test, it was exellent to holding at steam table and to reheat after holding room temperature within four hours and six hours each. Stir-Fry Pork: as a result of microbial analysis, in the case of holding at the steam table microbes increased safer two hours, but after four and six hours they little reduced. In the case of holding at room temperature the number of microbes increased according to the passage of time. As a result of sensory analysis, its taste of room temperature holding was fine until four and six hours each. Cooked Cuttlefish: as a microbial analysis, it was shown that the amount of total plate counts of room temperature holding ten times as high as the latter after six hours. As the result of sensory analysis, the cold holding was better until six hours and the room temperature holding was fine just until two hours. As a result of food poisoning bacteria, it was negative in every test in sample against Salmonella, Staphylococcus aureus, Vibrio parahaemolyticus.

• Proceedings of the Materials Research Society of Korea Conference
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• 2011.10a
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• pp.29.1-29.1
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• 2011

The selective catalytic reduction (SCR) of $MnO_x$ with $NH_3$ is an effective method for the removal of $MnO_x$ from stationary system. The typical catalyst for this method is $V_2O_5-WO_3(MoO_3)/TiO_2$, caused by the high activity and stability. However, This catalyst is active within $300{\sim}400^{\circ}C$ and occurs the pore plugging from the deposition of ammonium sulfate salts on the catalysts surface. It needs to locate the SCR unit after the desulfurizer and electrostatic precipitator without reheating of the flue gas as well as deposition of dust on the catalyst. The manganese oxides supported on titania catalysts have attracted interest because of its high SCR activity at low temperature. The catalytic activity of $MnO_x/TiO_2$ SCR catalyst with different manganese precursors have investigated for low-temperature SCR in terms of structural, morphological, and physico-chemical analyses. The $MnO_x/TiO_2$ were prepared from three different precursors such as manganese nitrate, manganese acetate (II), and manganese acetate (III) by the sol-gel method and then it calcinated at $500^{\circ}C$ for 2 hr. The structural analysis was carried out to identify the phase transition and the change intensity of catalytic activity by various manganese precursors was analyzed by FT-IR and Raman spectroscopy. These different precursors also led to various surface Mn concentrations indicated by SEM. The Mn acetate (III) tends to be more suppressive the crystalline phase (rutile), and it has not only smaller particle size, but also better distributed than the others. It was confirmed that the catalytic activity of MA (III)-$MnO_x/TiO_2$ was the highest among them.

• Korean journal of food and cookery science
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• v.23 no.2 s.98
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• pp.261-269
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• 2007

This study was performed to provide basic data for the sous vide cook-chill(SVCC) System by comparing and evaluating food quality, according to preparation method and days of storage, of foods that were prepared by SVCC to those prepared using the cook-chill(CC) System. Boiled quail eggs and fish paste in soy sauce were prepared using CC and SVCC and their quality was evaluated at the time of preparation and by days of storage. Viable cell counts were increased to 5.65(CC) and 3.40(SVCC) LogCFU/g by 15 days(p<.0001) and increased more over time in foods prepared with CC than with SVCC. For the CC method, Coliform counts increased to 4.58 LogCFU/g by 15 days(p<.0001). With SVCC, colirorms were not detected at 0 days, but counts reached 3.70 LogCFU/g by 15 days(p<.0001). After reheating, no coliforms were detected for CC or SVCC at 0 days, however, by 15 days, coliform counts reached 3.61 and 2.52 LogCFU/g(p<.0001) for CC and SVCC, respectively. Finally, the sensory scores of SVCC were higher than those of CC.

• Korean journal of food and cookery science
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• v.24 no.5
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• pp.713-721
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• 2008

The principal objective of this study was to evaluate the microbiological quality of Glazed Spanish Mackerel in Teriyaki sauce by adding Lemon juice, using a Sous vide Cook-chill method. The control was prepared by mixing 100 g of cut Spanish Mackerel and 15 mL of Teriyaki sauce. 1.5 mL lemon juice was added to 15 mL of Teriyaki sauce. The product was stored at below $3^{\circ}C$, and its microbiological quality was assessed over varying storage periods (0, 5, 10, 15 days). Total Plate Counts at product flow showed no significant difference between the control and the lemon juice-added sample. However, the coliform counts at the end of mixing each sauce were detected at low levels of 1.65 Log CFU/g in the lemon juice-added sample, as opposed to 2.63 Log CFU/g in the controls (p<0.05). The microbiological quality by storage day was relatively high in the lemon juice-added samples. After reheating, the Total Plate Counts and Coliform counts of the lemon juice-added samples satisfied the standard applied in the processed food (5.0 and 2.0 Log CFU/g, respectively). It can be concluded that the addition of Lemon juice was more effective in ensuring the safety and extending the shelf life of Sous vide Glazed Spanish Mackerel in Teriyaki sauce.

• The Journal of the Korea institute of electronic communication sciences
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• v.18 no.3
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• pp.483-494
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• 2023

Recently, gas turbine generators are widely used for frequency control of power systems. Although the inlet temperature of a gas turbine is a key factor related to the performance and lifespan of the device, the inlet temperature is not measured directly for reasons such as the turbine structure and operating environment. In particular, the inlet temperature of the reheating gas turbine is very important for stable operation management, but field workers are experiencing a lot of difficulties because the manufacturer does not provide information on the calculation formula. Therefore, in this study, we propose a method for estimating the inlet temperature of a gas turbine using a machine learning-based linear regression analysis method based on a polytropic process equation. In addition, by proposing an inlet temperature calculation algorithm through the usefulness analysis and verification of the inlet temperature calculation model obtained through linear regression analysis, it is intended to help to improve the level of reheat gas turbine combustion tuning technology.

• Korean Journal of Materials Research
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• v.2 no.6
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• pp.452-460
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• 1992

Effects of the microalloyed elements, temperatures and cooling rates on the strength and toughness of the medium carbon microalloyed hot forging steels obtained by air cooling(A.C.) method and the low carbon microalloyed forging steels by direct quenching(D.Q.) method were investigated. Combined additions of V+Nb produced the optimum combination of strength and toughness with ferrite-pearlite structure of the medium carbon steel by the A.C. method. 831MPa in UTS and 52.1J in toughness were obtained for 0.40c+0.12V+0.07Nb. It was martensite structure for the low carbon steel by the D.Q. method. The highest UTS and toughness obtained by Mo additions were 855MPa and 108j by 0.12C+0.10V+0.03Nb+1.13Mo respectively. Especially, the toughness of the low carbon steel was twice better than that of the medium carbon steel. 110$0^{\circ}C$was more appropriate than 120$0^{\circ}C$ for the reheating and forging temperature and 1.$2^{\circ}C$ /s was the best cooling rate from the viewpoint of the strength and toughness. Multiple regression analysis was used to quantify the influence of the microalloyed elements, temperatures and cooling rates on the strength, toughness, austenite grain size, and the pearlite interlamellar spacing.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.29 no.5
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• pp.681-688
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• 1996

To investigate the effort of drying methods on the physicochemical properties of agar, gel strength, viscosity, melting and setting point, and phase transition by differential scanning calorimetery (DSC) during its heating were determined. In addition the structural differences of agar powder by scanning electron microscope (SEM) was examined. The most shortest onset temperature of gel strength increase was extruding method among any other methods. Viscosity of agar with hot air method, 400.00 cps at $45^{\circ}C$, was markedly increased, but with spraying and extruding ones were little change. The melting and setting point, and the temperature for maximum endothermic and enthalpy for agar with extruding one, $80.01^{\circ}C,\;36.05^{\circ}C\;and\;61.72^{\circ}C,\;0.73\;cal/g$, respectively, were lowest among the drying ones. But in the case of reheating after gelling, there were little change in all methods. Observing the surface structure of agar with SEM, extruding method showed the most unstable with absorptive property.