• Journal of The Geomorphological Association of Korea
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• v.15 no.2
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• pp.67-83
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• 2008

To find out the process of hillslope denudation since the Last Glacial Maximum in Asan area, we conducted the stratiform interpretation and carbon age measurements with the collected samples through trenching in the valley bottom of 'Agol' located in the lower stream of Magok stream. The results are as follows. 11 inorganic and 8 organic matter layers were confirmed at the point of trench MG1 in the subject area, 7 inorganic and 3 organic at the point of trench MG2, and 5 inorganic and 3 organic at the point of trench MG3, respectively. The frequency of hillslope denudation, hillslope mass movement, which had occurred in the unstable environment of back hillslope at the point of MG 1, was 11 times (8 times before about 2,900yrBP, twice in between about 2,900~1,900yrBP, and once after about 1,900yrBP) as a whole. The frequency of moor which had formed in the comparatively stable environment of back hillslope was 9 times (5 times before about 3,000yrBP, twice in between 3,000~2,800yrBP, and once in between 2,200~1,900yrBP) at minimum. The frequency of back hillslope denudation at the point of MG2 was totally 7 times (4 times before about 1,900yrBP and 3 times after about 1,900yrBP) and the moor formations were 3 times (twice before about 1,900yrBP and once after 1,900yrBP). The frequency of back hillslope denudation at the point of MG3 was totally 5 times (3 times before about 1,900yrBP and twice after about 1,900yrBP) and the moor formations were 3 times (twice before about 1,900yrBP and once after 1,900yrBP). The hillslope surrounded by valley bottom of 'Agol' was confirmed as the pile up of various inorganic matters by the mass movement such as sand or sandy gravel in the valley bottom of the subject area, formed not once but several times of denudation. We could know that the hillslope denudation cycle converged to the time period of $10^2{\sim}10^3$ years. These results will be an important basic data for restoring hillslope denudation process near Asan and changing climate of the Late Quaternary Period.

• Korean Journal of Social Welfare Studies
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• no.37
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• pp.319-344
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• 2008

The Purpose of this study is to observe the existence of welfare attitude split between welfare regimes clique and to explore the effect of institutional(regime) characteristics on welfare attitude. And Second purpose is to find the characteristics of structure of welfare attitude and then to clarify the characteristics of welfare attitude in Korea. This work contribute to find the point of solidarity and split and to work out the strategical clues for constructing pro-welfare politics. To compare the attitude on the state responsibility about the welfare, Sweden, France, US, and Korea is selected. And the effect of sex, age, education level, income class, and labor status which are abstracted from existing welfare state comparative study are analyzed. The result show the difference in welfare attitude score between countries. The welfare attitude score is Sweden, France and US in order. the Score in Korea is lowest. In the case of the effect structure of welfare attitude between countries, there are no differences between Sweden and France. But the specific characteristics in US and Korea, are observed. And the effect structure of sex, class, labor status is equal in Sweden, France, and US. That is, women, people in low class, and people in low labor status more emphasize the state responsibility on the welfare. But the effect structure of age of US is different comparing other countries. In US, the old age is tend to less support the state responsibility. The education level operate as the effect factor in only US. And Korea show the different effect structure on the welfare attitude. This understanding about structure of welfare consciousness become the basis to construct the strategy for welfare state by proposing the point of consensus and conflict to conversion of welfare paradigm.

• Proceedings of the Korean Society of Propulsion Engineers Conference
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• 2011.04a
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• pp.1-2
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• 2011

Hybrid rockets have lately attracted attention as a strong candidate of small, low cost, safe and reliable launch vehicles. A significant topic is that the first commercially sponsored space ship, SpaceShipOne vehicle chose a hybrid rocket. The main factors for the choice were safety of operation, system cost, quick turnaround, and thrust termination. In Japan, five universities including Hokkaido University and three private companies organized "Hybrid Rocket Research Group" from 1998 to 2002. Their main purpose was to downsize the cost and scale of rocket experiments. In 2002, UNISEC (University Space Engineering Consortium) and HASTIC (Hokkaido Aerospace Science and Technology Incubation Center) took over the educational and R&D rocket activities respectively and the research group dissolved. In 2008, JAXA/ISAS and eleven universities formed "Hybrid Rocket Research Working Group" as a subcommittee of the Steering Committee for Space Engineering in ISAS. Their goal is to demonstrate technical feasibility of lowcost and high frequency launches of nano/micro satellites into sun-synchronous orbits. Hybrid rockets use a combination of solid and liquid propellants. Usually the fuel is in a solid phase. A serious problem of hybrid rockets is the low regression rate of the solid fuel. In single port hybrids the low regression rate below 1 mm/s causes large L/D exceeding a hundred and small fuel loading ratio falling below 0.3. Multi-port hybrids are a typical solution to solve this problem. However, this solution is not the mainstream in Japan. Another approach is to use high regression rate fuels. For example, a fuel regression rate of 4 mm/s decreases L/D to around 10 and increases the loading ratio to around 0.75. Liquefying fuels such as paraffins are strong candidates for high regression fuels and subject of active research in Japan too. Nakagawa et al. in Tokai University employed EVA (Ethylene Vinyl Acetate) to modify viscosity of paraffin based fuels and investigated the effect of viscosity on regression rates. Wada et al. in Akita University employed LTP (Low melting ThermoPlastic) as another candidate of liquefying fuels and demonstrated high regression rates comparable to paraffin fuels. Hori et al. in JAXA/ISAS employed glycidylazide-poly(ethylene glycol) (GAP-PEG) copolymers as high regression rate fuels and modified the combustion characteristics by changing the PEG mixing ratio. Regression rate improvement by changing internal ballistics is another stream of research. The author proposed a new fuel configuration named "CAMUI" in 1998. CAMUI comes from an abbreviation of "cascaded multistage impinging-jet" meaning the distinctive flow field. A CAMUI type fuel grain consists of several cylindrical fuel blocks with two ports in axial direction. The port alignment shifts 90 degrees with each other to make jets out of ports impinge on the upstream end face of the downstream fuel block, resulting in intense heat transfer to the fuel. Yuasa et al. in Tokyo Metropolitan University employed swirling injection method and improved regression rates more than three times higher. However, regression rate distribution along the axis is not uniform due to the decay of the swirl strength. Aso et al. in Kyushu University employed multi-swirl injection to solve this problem. Combinations of swirling injection and paraffin based fuel have been tried and some results show very high regression rates exceeding ten times of conventional one. High fuel regression rates by new fuel, new internal ballistics, or combination of them require faster fuel-oxidizer mixing to maintain combustion efficiency. Nakagawa et al. succeeded to improve combustion efficiency of a paraffin-based fuel from 77% to 96% by a baffle plate. Another effective approach some researchers are trying is to use an aft-chamber to increase residence time. Better understanding of the new flow fields is necessary to reveal basic mechanisms of regression enhancement. Yuasa et al. visualized the combustion field in a swirling injection type motor. Nakagawa et al. observed boundary layer combustion of wax-based fuels. To understand detailed flow structures in swirling flow type hybrids, Sawada et al. (Tohoku Univ.), Teramoto et al. (Univ. of Tokyo), Shimada et al. (ISAS), and Tsuboi et al. (Kyushu Inst. Tech.) are trying to simulate the flow field numerically. Main challenges are turbulent reaction, stiffness due to low Mach number flow, fuel regression model, and other non-steady phenomena. Oshima et al. in Hokkaido University simulated CAMUI type flow fields and discussed correspondence relation between regression distribution of a burning surface and the vortex structure over the surface.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.20 no.6
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• pp.427-446
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• 2008

A review on the papers published in the Korean Journal of Air-Conditioning and Refrigeration Engineering in 2006 has been accomplished. Focus has been put on current status of research in the aspect of heating, cooling, ventilation, sanitation and building environments. The conclusions are as follows. (1) The research trends of fluid engineering have been surveyed as groups of general fluid flow, fluid machinery and piping, etc. New research topics include micro heat exchanger and siphon cooling device using nano-fluid. Traditional CFD and flow visualization methods were still popular and widely used in research and development. Studies about diffusers and compressors were performed in fluid machinery. Characteristics of flow and heat transfer and piping optimization were studied in piping systems. (2) The papers on heat transfer have been categorized into heat transfer characteristics, heat exchangers, heat pipes, and two-phase heat transfer. The topics on heat transfer characteristics in general include thermal transport in a cryo-chamber, a LCD panel, a dryer, and heat generating electronics. Heat exchangers investigated include pin-tube type, plate type, ventilation air-to-air type, and heat transfer enhancing tubes. The research on a reversible loop heat pipe, the influence of NCG charging mass on heat transport capacity, and the chilling start-up characteristics in a heat pipe were reported. In two-phase heat transfer area, the studies on frost growth, ice slurry formation and liquid spray cooling were presented. The studies on the boiling of R-290 and the application of carbon nanotubes to enhance boiling were noticeable in this research area. (3) Many studies on refrigeration and air conditioning systems were presented on the practical issues of the performance and reliability enhancement. The air conditioning system with multi indoor units caught attention in several research works. The issues on the refrigerant charge and the control algorithm were treated. The systems with alternative refrigerants were also studied. Carbon dioxide, hydrocarbons and their mixtures were considered and the heat transfer correlations were proposed. (4) Due to high oil prices, energy consumption have been attentioned in mechanical building systems. Research works have been reviewed in this field by grouping into the research on heat and cold sources, air conditioning and cleaning research, ventilation and fire research including tunnel ventilation, and piping system research. The papers involve the promotion of efficient or effective use of energy, which helps to save energy and results in reduced environmental pollution and operating cost. (5) Studies on indoor air quality took a great portion in the field of building environments. Various other subjects such as indoor thermal comfort were also investigated through computer simulation, case study, and field experiment. Studies on energy include not only optimization study and economic analysis of building equipments but also usability of renewable energy in geothermal and solar systems.

• Journal of the Society of Cosmetic Scientists of Korea
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• v.34 no.3
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• pp.189-200
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• 2008

In this study, the antioxidative effects, inhibitory effects on elastase, and components of Quercus glauca extracts were investigated. The free radical (1,1-diphenyl-2-picrylhydrazyl, DPPH) scavenging activity $(FSC_{50})$ of extract I fractions of Quercus glauca leaf was in the order: 50% ethanol extract $(12.45{\mu}g/mL)$ < ethyl acetate fraction $(10.47{\mu}g/mL)$ < deglycosylated flavonoid aglycone fraction $(8.57{\mu}g/mL)$. Reactive oxygen species (ROS) scavenging activities $(OSC_{50})$ of some Quercus glauca leaf extracts on ROS generated in $Fe^{3+}-EDTA/H_2O_2$ system were investigated using the luminol-dependent chemiluminescence assay. The order of ROS scavenging activity was 50% ethanol extract $(OSC_{50},\;4.2{\mu}g/mL)$ < deglycosylated flavonoid aglycone fraction $(1.58{\mu}ug/mL)$ < ethyl acetate fraction $(0.66{\mu}g/mL)$. Ethyl acetate fraction showed the most prominent scavenging activity. The protective effects of extract / fractions of Quercus glauca leaf on the rose-bengal sensitized photohemolysis of human erythrocytes were investigated. The Quercus glauca leaf extracts suppressed photohemolysis in a dose dependent manner, particularly deglycosylated flavonoid aglycone fraction exhibited the most prominent celluar protective effect $({\tau}_{50}$, 398.67 min at $50{\mu}g/mL$). Aglycone fractions obtained from the deglycosylation reaction of ethyl acetate fraction among the Quercus glauca leaf extracts, showed 2 bands in TLC and 2 peaks in HPLC experiments (360 nm) as well. Two components were identified as quercetin (55.77%), and kaempferol (44.23 %). TLC chromatogram of ethyl acetate fraction of Quercus glauca leaf extracts revealed 6 bands $(QG1{\sim}QG6)$, Among them, isoquercitrin (QG3), hyperin (QG4), and rutin (QG6) were identified. The inhibitory effect of aglycone fraction on tyrosinase $(IC_{50},\;73.5{\mu}g/mL)$ and elastase $(IC_{50},\;16.2{\mu}g/mL)$ was high. These results indicate that extract / fractions of Quercus glauca can function as antioxidants in biological systems, particularly skin exposed to UV radiation by scavenging $^1O_2$ and other ROS, and protect cellular membranes against ROS. And component analysis of Quercus glauca leaf extract and inhibitory activity on tyeisinase and elastase of the aglycone fraction could be applicable to new functional cosmetics.

• Journal of the Society of Cosmetic Scientists of Korea
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• v.34 no.3
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• pp.157-165
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• 2008

In the previous study, the anti-oxidant activity of oxtract/fraction of Sueada aspparagoides(SA) and the stability test for the cream containing SA extract were investigated respectively[1,2]. In this study, the components of SA extract were analyzed by TLC, HPLC, and LC/ESI-MS/MS, $^1H$-NMR. TLC chromatogram of ethyl acetate fraction of SA extract revealed 5 bands $(SA1{\sim}SA5)$. HPLC chromatogram of aglycone fractions obtained from deglycoylation reaction of ethyl acetate fraction showed 2 bands (SAA 2 and SAA 1), which were identified as quercetin (composition ratio, 16.88%) and kaempferol (83.12%) in the order of elution time. Among 5 bands of TLC chromatogram, 4 bands $(SA2{\sim}SA5)$ also were Identified as kaempferol-3-O-glucoside (SA 2), quercetin-3-O-glucoside (SA3), kaempferol-3-O-rutinoside (SA 4), quercetin-3-O-rutinoside (SA 5) by LC/ESI-MS/MSMS/MS. respectively. The spectrum generated for SAA 1 by LC/ESI-MS/MS in the negative ion mode also gave the ion corresponding to the deprotonated aglycone $[M-H]^-$ (285m/z), the $^1H$-NMR spectrum contained signals [${\delta}$ 6.19 (1H, d, J=1.8Hz, H-6), ${\delta}$ 6.44 (1H, d, J=1.8Hz, H-8), ${\delta}$ 6.92 (2H, d, J=9.0Hz, H-3', 5'), ${\delta}$ 8.04 (2H, d, J=9.0Hz, H-2', 6', thus SAA 1 was identified as kaempferol. SAA 2 yielded the deprotonated agycone ion $[M-H]^-$ (301m/z), $^1H$-NMR spectrum showed signals [${\delta}$ 6.20 (1H, d, J=2.0Hz, H-6), ${\delta}$ 6.42 (1H, d, J=2.0Hz, H-8), ${\delta}$ 6.90 (1H, d, J=8.6Hz, H-5'), ${\delta}$ 7.55 (1H, dd, J=8.6, 2.2Hz, H-6'), ${\delta}$ 7.69 (1H, d, J=2.2Hz, H-2', thus SAA 2 was Identified as quercetin. In conclusion, with the anti-oxidant activity and the stability test reported previously, component analysis of SA extracts could be applicable to new cosmeceuticals.

• The Journal of Korean Obstetrics and Gynecology
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• v.21 no.3
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• pp.34-59
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• 2008

Purpose: This study was performed to investigate the inhibiting effects of Gungguijohyeoleum on the development of experimentally-induced endometriosis in rats. Methods: Endometriosis was induced in rats by autotransplanting uterine tissue to the peritoneum and we divided them into three groups: (1) sham-operated group(n=8), (2) surgically induced endometriosis and untreated control group(n=8), (3) surgically induced endometriosis and Gungguijohyeoleum treated group(n=8), Gungguijohyeoleum was orally administrated for 15 days after operation. Then we measured the body weight, the volumes of endometriotic implants, the weight of uterus and ovary, and investigated the concentrations of cytokines(MCP-1, $TNF-{\alpha}$, $IL-1{\beta}$, IL-6) in peritoneal fluids. Histopathology, immunohistochemistry for COX-2 and VEGF, and histochemistry for mast cell in transplanted uterine tissue were performed. Results: - The volume ($mm^3$) of endometriotic implants in Gungguijohyeoleum treated group ($76.4{\pm}24.5$) was significantly decreased(p<0.05) compared with control group($222.1{\pm}109.1$). - The concentration (pg/ml) of MCP-1 in peritoneal fluids in Gungguijohyeoleum treated group ($1060.8{\pm}280.8$) was significantly decreased(p<0.05) compared with control group($1412.5{\pm}345.7$). - The concentration (pg/ml) of $TNF-{\alpha}$ in peritoneal fluids in Gungguijohyeoleum treated group ($827.5{\pm}219.9$) was significantly decreased(p<0.01) compared with control group($1126.2{\pm}139.9$). - The concentration (pg/ml) of $IL-1{\beta}$ in peritoneal fluids in Gungguijohyeoleum treated group($83.4{\pm}9.0$) was significantly decreased(p<0.01) compared with control group($105.3{\pm}17.6$). - The concentration (pg/ml) of IL-6 in peritoneal fluids in Gungguijohyeoleum treated group($108.9{\pm}15.7$) was decreased compared with control group($122.8{\pm}19.3$). - Histopathologically, proliferation of endometriotic epithelia, infiltration of inflammatory cells and angiogenesis in transplanted uterine tissue of Gungguijohyeoleum treated group were weakly observed than those of control group. - The percentage(%) of positive epithelial layers for COX-2 in Gungguijohyeoleum treated group($56.8{\pm}12.8$) was significantly decreased(p<0.01) compared with control group($75.1{\pm}16.3$). -The VEGF expression of endometriotic epithelia, neovascular endothelia and stromal cells in transplanted uterine tissue of Gungguijohyeoleum treated group was weakly observed than that of control group. - The numbers of mast cells in transplanted uterine tissue in Gungguijohyeoleum treated group($35.4{\pm}18.4$) were significantly decreased(p<0.01) compared with control group ($91.0{\pm}28.3$). Conclusion: On the basis of these results, we concluded that Gungguijohyeoleum has inhibiting effects on the development of transplanted uterine tissue. And these effects may be related with decreased production of MCP-1, $TNF-{\alpha}$, $IL-1{\beta}$, COX-2, VEGF and mast cells by administration of Gungguijohyeoleum.

• Food Science and Preservation
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• v.15 no.5
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• pp.675-681
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• 2008

This study investigatedthe quality of mashed red pepper after application of various freezing and thawing conditions. Two freezing temperatures ($-70^{\circ}C$, $-10^{\circ}C$), two thawing temperatures ($0^{\circ}C$, $40^{\circ}C$), and two thawing methods (water-thawing, air-thawing), were employed. Changes in levels of capsaicinoids, vitamin C, free sugars, organic acids, and capsanthin were measured. Capsaicinoids, vitamin C,and free sugar contents were lowest in pepper treated at $-10^{\circ}C/40^{\circ}C$ (freezing/thawing), and the loss rates were 38.0, 79.4 and 24.6%, respectively. When thawing methods were compared, chemical contents were higher in air-thawed samples than in water-thawed peppers, but there was a statistically significant difference only in vitamin C content. Free sugar content after $-70^{\circ}C$ freezing were higher than after $-10^{\circ}C$ freezing, irrespective of the thawing method used. Initial citric acid, malic acid, and succinic acid contents were 44.90, 30.76 and 20.65 mg/100 g, and there was no significant difference between peppers treated with different freezing and thawing conditions. It is recommended that the best method for preserving the overall quality of mashed red pepper is freezing at $-70^{\circ}C$ and thawing at $0^{\circ}C$ in air.

• Food Science and Preservation
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• v.15 no.5
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• pp.725-730
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• 2008

The effects of acetic acid fermented juice prepared with submerged culture media of Antrodia camphorata mycelium (AJA: pH 3.2, acidity 2.0, Brix degree 3.2) on blood glucose levels and serum lipid profiles of rats in which diabetes was induced with streptozotocin (STZ) were investigated. Rats were divided into normal controls (NC), diabetic controls (DM), and groups receiving diluted (1:1, with water) AJA (A1) and undiluted AJA (A2). The volume of liquid given to both A1 and A2 animals was 0.5 mL/100 g body weight. In the A1 and A2 groups, compared with the DM group, polyphagia, liver enlargement, and weight loss caused by diabetes were considerably alleviated, but did not attain the levels of NC group rats. In the A1 and A2 groups, the levels of blood glucose were 17.1% and 28.2% lower than in the DM group. There was no significant difference in the levels of fructosamine between the DM and A1 group, but the A2 group had a level 16.3% lower than the DM group. In the A1 and A2 groups, compared with the DM group, serum triglyceride levels decreased by 44.1-48.0%, serum total cholesterol by 24.0-31.1%, and serum LDL-cholesterol by 25.2-51.1%. The level of HDL-cholesterol in A2 animals rose by 45.9% compared to NC rats. The results show that AJA may be a useful beverage for diabetes patients, offering both antihyperglycemic activity and improvement in levels of serum lipids.

• Food Science and Preservation
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• v.15 no.5
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• pp.635-641
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• 2008

This study was conducted to investigate the optimal sub-zero temperature for storage of two garlic cultivars, the northern ecotype 'Jaerae' and the southern ecotype 'Daeseo'. These cultivars of garlic bulbs were stored at different temperature (room temperature, $0^{\circ}C$, and $-4^{\circ}C$) conditions after predrying. Southern ecotype garlic showed higher weight loss than northern ecotype garlic. Northern ecotype garlic at $-4^{\circ}C$ exhibited less than 5% of weight loss during 10 month storage. Sprouting rate was higher in southern than in northern ecotype at room temperature storage. The value of injury by disease and insect was similar between southern ecotype and northern ecotype for 5 month storage, and then northern ecotype showed higher value of injury by disease and insect than southern ecotype. Hunter 'b' value of northern ecotype garlic was the lowest at $-4^{\circ}C$ storage. Northern ecotype garlic showed no cold injury at freezing point temperature storage. However, southern ecotype garlic had $0{\sim}5.3%$ cold injury occurrence at $-4^{\circ}C$ storage. Respiration and ethylene production exhibited the highest at room temperature storage, those had the slight increase at $0^{\circ}C$ and $-4^{\circ}C$ storages. Northern ecotype showed higher enzymatic pyruvic acid and fructan contents than those of southern ecotype. Enzymatic pyruvic acid content increased and fructan contents decreased during storage time.