• 한국신재생에너지학회:학술대회논문집
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• 2010.06a
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• pp.123.2-123.2
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• 2010

Fuel Cell cogeneration system is a promising technology for generating electricity and heat with high efficiency of low pollutant emission. We have been developed 5kW class fuel cell cogeneration system for commercial and residential application. The fuel processor is a crucial part of producing hydrogen from the fossil fuels such as LNG and LPG. The 5kW class high efficiency fuel processor consists of steam reformer, CO shift converter, CO preferential oxidation(PrOx) reactor, burner and heat exchanger. The one-stage CO shift converter process using a metal oxide catalyst was adopted. The efficiency of 5 kW class fuel processor shows 75% based on LHV. In addition, for the purpose of continuous operation with load fluctuations in the commercial system for residential use, load change of fuel processor was tested. Efficiency of 30%, 50%, 70% and 100% load shows 75%, 75%, 73% and 72%(LHV), respectively. Also, during the load change conditions, the product gas composition was stable and the outlet CO concentration was below 5 ppm. The Fuel processor operation was carried out in residential fuel cell cogeneration system with fuel cell stack under dynamic conditions. The 5kW class fuel processor have been evaluated for long-term durability and reliability test including with improvement in optimal operation logic.

• Journal of Welding and Joining
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• v.30 no.6
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• pp.126-132
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• 2012

The GMA welding process involves large number of interdependent variables which may affect product quality, productivity and cost effectiveness. The relationships between process parameters for a fillet joint and bead geometry are complex because a number of process parameters are involved. To make the automated GMA welding, a method that predicts bead geometry and accomplishes the desired mechanical properties of the weldment should be developed. The developed method should also cover a wide range of material thicknesses and be applicable for all welding position. For the automatic welding system, the data must be available in the form of mathematical equations. In this study a new intelligent model with genetic algorithm has been proposed to investigate interrelationships between welding parameters and bead geometry for the automated GMA welding process. Through the developed model, the correlation between process parameters and bead geometry obtained from the actual experimental results, predicts that data did not show much of a difference, which means that it is quite suitable for the developed genetic algorithm. Progress to be able to control the process parameters in order to obtain the desired bead shape, as well as the systematic study of the genetic algorithm was developed on the basis of the data obtained through the experiments in this study can be applied. In addition, the developed genetic algorithm has the ability to predict the bead shape of the experimental results with satisfactory accuracy.

• Asian-Australasian Journal of Animal Sciences
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• v.30 no.8
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• pp.1168-1174
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• 2017

Objective: The aim of the study was to evaluate the effects of different nitrate levels (150, 300, 450, and 600 ppm $KNO_3$) on the volatile compounds and some other properties of pastırma. Methods: Pastırma samples were produced under the controlled condition and analyses of volatile compounds, and thiobarbituric acid reactive substances (TBARS) as an indicator of lipid oxidation, non-protein nitrogenous matter content as an indicator of proteolysis, color and residual nitrite were carried out on the final product. The profile of volatile compounds of pastırma samples was analyzed by gas chromatography/mass spectrometry using a solid phase microextraction. Results: Nitrate level had a significant effect on pH value (p<0.05) and a very significant effect on TBARS value (p<0.01). No significant differences were determined in terms of $a_w$ value, non-protein nitrogenous substance content, color and residual nitrite between pastırma groups produced by using different nitrate levels. Nitrate level had a significant (p<0.05) or a very significant (p<0.01) effect on some volatile compounds. It was determined that the amounts and counts of volatile compounds were lower in the 450 and especially 600 ppm nitrate levels than 150 and 300 ppm nitrate levels (p<0.05). While the use of 600 ppm nitrate did not cause an increase in residual nitrite levels, the use of 150 ppm nitrate did not negatively affect the color of pastırma. However, the levels of volatile compounds decreased with an increasing level of nitrate. Conclusion: The use of 600 ppm nitrate is not a risk in terms of residual nitrite in pastırma produced under controlled condition, however, this level is not suitable due to decrease in the amount of volatile compounds.

• Journal of the Korean Recycled Construction Resources Institute
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• v.2 no.4
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• pp.291-296
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• 2014

For the purpose of energy consumption and green-house gas reduction from building, new insulation materials with improved thermal property have been developed and used. Among new insulation materials, mineral hydrate which compensates for the defects of existing materials is using as a prominent insulation material. The fabrication method of mineral hydrate is similar to that of ALC for building structure but mineral hydrate is only used for insulation. The raw materials that make up of mineral hydrate are cement, lime and anhydrite. Especially anhydrite is all dependant on imports. In this study, Desulfurization Gypsum(DG), by-product of oil plant, was used for replacing for imported anhydrite and waste recycling. DG substituted all of anhydrite and a part of lime. Mineral hydrate used DG had analogous thermal and physical properties, compared to existing mineral hydrate.

• Natural Product Sciences
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• v.24 no.3
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• pp.181-188
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• 2018

Caryopteris incana (Verbenaceae) has been used to treat cough, arthritis, and eczema in Oriental medicine. The two fractions ($CHCl_3-$ and BuOH fractions) and the essential oil of the plant material were subjected to the inducible nitric oxide synthase (iNOS) assay. The $IC_{50}$ of the $CHCl_3$ fraction and the essential oil on LPS-induced macrophage RAW 264.7 cells were $16.4{\mu}g/mL$ and $23.08{\mu}g/mL$, respectively. On gas chromatography (GC)-mass spectroscopy (MS) analysis, twenty-five components representing 85.5% amount of total essential oil were identified. On the chromatogram, three main substances, trans-pinocarveol, cis-citral, and pinocarvone, occupied 18.8%, 13.5% and 18.37% of total peak area. Furthermore, by HPLC-UV analysis, six compounds including one iridoid (8-O-acetylharpagide)- and five phenylethanoid glycosides (caryopteroside, acteoside, phlinoside A, 6-O-caffeoylphlinoside, and leucosceptoside A) isolated from the BuOH fraction were quantified. The content of six compounds were shown as the following order: caryopteroside (162.35 mg/g) > 8-O-acetylharpagide (93.28 mg/g) > 6-O-caffeoylphlinoside (28.15 mg/g) > phlinoside (22.60 mg/g) > leucosceptoside A (16.87 mg) > acteoside (7.05 mg/g).

• Transactions of the Korean hydrogen and new energy society
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• v.26 no.6
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• pp.629-637
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• 2015

As concern about energy security and global warming many countries have been making effort to reduce fossil fuel. In the case of US, as one of the efforts, the standards of the alcohol vehicle fuels(including blended with gasoline) have been established. Alcohol is known that make some trouble concerning startability, durability and corrosion when using as fuel of a conventional vehicle. For these reason, alcohol usage needs not only the fuel standard, but also a modified car. In the case of Korea, although there are no the standard and the modified vehicle yet, high concentration alcohol blended fuel has being sold at illegal market. In this study, exhaust gas and performance of the conventional vehicle that alcohol(methanol and isopropyl alcohol) blends were fueled were measured to notify danger of using them without preparation of institutional arrangements. Also, to analyze correlation characteristics of the fuels and them, property test of the fuels was conducted. The test result show that bad-startability caused by low RVP and high T10 affected increase in NMOG and CO. NOx was increased under the highest short term fuel trim caused by high Oxygen content and low NHV of alcohol. According to increasing as alcohol content, fuel economy and acceleration ability were decreased but $CO_2$ was not significantly decreased.

• Tuberculosis and Respiratory Diseases
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• v.62 no.3
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• pp.223-226
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• 2007

Tetrafluoroethylene is a colorless gas that can be used to synthesize a variety of fluoride compounds by polymerization (e.g., Teflon). Fluoride compounds have many applications in industry. There are several reports of inhalation injury from the pyrolytic product of fluoride compounds. When the polymer is heated under the conditions of inadequate ventilation, the fumes can cause polymer fume fever or pulmonary edema which manifested as symptoms such as fever, chill, profuse sweating, cough and dyspnea. However there are no reports of a direct lung injury caused by tetrafluoroethylene. We report a case of a 27-year-old male presented with acute lung injury after inhaling concentrated tetrafluoroethylene. He complained of cough and dyspnea after the accidental inhalation of tetrfluoroethylene at his workplace. The symptoms improved without any complications after conservative treatment with oxygen and steroid.

• Journal of Food Hygiene and Safety
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• v.23 no.2
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• pp.91-97
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• 2008

Kimchi is a representative traditional food in Korea and a type of vegetable product that is the unique complex lactic acid fermentation in the world. It can be considered as a unique fermented food generated by various flavors, which are not included in raw materials, that can be generated by mixing and fermenting various spices and seasonings, such as red pepper powder, garlic, ginger, and salted fish, added to Chinese cabbages. Functionalities in Kimchi have been approved through several studies and the probiotic function that is mainly based on lactic acid bacteria including their physical functions in its contents has also verified. Studies on the verification of the safety of Kimchi including its physiological functions have been conducted. In particular, the function of lactic acid bacteria, which is a caused of the fermentation of Kimchi. Although the lactic acid bacteria contributed to the fermentation of Kimchi is generated from raw and sub-materials, the lactic acid bacteria attached on Chinese cabbages has a major role in the process in which the fermentation temperature and dominant bacteria are also related to the process. The salt used in a salt pickling process inhibits the growth of the putrefactive and food poisoning bacteria included in the fermentation process of Kimchi and of other bacteria except for such lactic acid bacteria due to the lactic acid and several antimicrobial substances generated in the fermentation process, such as bacteriocin and hydrogen peroxide. In addition, the carbon dioxide gas caused by heterolactic acid bacteria contributes to the inhibition of aerobic bacteria. Furthermore, special ingredients included in sub-materials, such as garlic, ginger, and red pepper powder, contribute to the inhibition of putrefactive and food poisoning bacteria. The induction of the change in the intestinal bacteria as taking Kimchi have already verified. In conclusion, Kimchi has been approved as a safety food due to the fact that the inhibition of food poisoning bacteria occurs in the fermentation process of Kimchi and the extinction of such bacteria.

• 한국생물공학회:학술대회논문집
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• 2003.10a
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• pp.422-427
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• 2003

Rhodopseudomonas palustris P4 can produce $H_2$ either from CO by water-gas shift reaction or from various sugars by anaerobic fermentation. Fermentative $H_2$ production by P4 is fast, but its yield is relatively low due to the formation of various organic acids. In order to increase $H_2$ production yield from glucose, P4 was investigated for the photo-fermentation of acetate which is a major by-product of fermentative $H_2$ production. Experiments were performed in batch modes using both light-grown and dark-grown cells. When the dark-grown P4 was challenged with light and acetate, $H_2$ was produced with the consumption of acetate after a lag period of 25 h. $H_2$ production was inhibited when a nitrogen source, especially ammonium, is present. When the dark-fermentation broth containing acetate was adopted for photo-fermentation with light-grown cells, $H_2$ production and concomitant acetate consumption occurred without a lag period. The $H_2$ yield was estimated as 2.4 - 2.8 mol $H_2/mol$ acetate and the specific $H_2$ production rate was as 9.8 ml $H_2/g$ cell${\cdot}$h, The fact that a single strain can perform both dark- and light-fermentation gives a great advantage in process development Compared to a one-step dark-fermentation, the combined dark- and light-fermentation can increase the $H_2$ production yield on glucose by two-fold.

• Journal of the Korea Computer Industry Society
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• v.8 no.1
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• pp.49-56
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• 2007

Various kind of laser had been used on addition to endoscope for obstetrics and gynecology, gas laser such as CO2 laser had been used mainly much in laparoscope surgical operation mainly Thermal effect of beam displays other result different component parts of cellular tissue and different close of a marketplace of laser beam and priority solidification of temperature increase consists in cellular tissue, and cutting or carbonization process happens and evaporation by breakdown of cellular tissue happens more than $300^{\circ}$. <중략> Ostabilization of pulse transformer by high tension output module of CO2analog laser for obstetrics and gynecology that accomplish marks of honor kind switching and accuracy is required, and stabilize with laser output applying Turn-off in existent hard switching forward converter, on city happened switching damage, damage increase of output diode station recovery special quality, parasitism shock, design and result that manufacture, brought result that improve than existing product. Will be bought to get into superior result if supplement as systematic late.