• Journal of Korea Soil Environment Society
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• v.5 no.2
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• pp.55-66
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• 2000

A U.S EPA Synthetic soil matrix was used for reference neat soil and pyrene contaminated soil. For the contaminated soil, 4.79 wt.% pyrene was dissolved completely into the djchlorornethane, and the soil was evenly soaked with the pyrene solution. The contaminated soil samples(50$\pm$0.5mg) were heated in a modified electrical screen heater reactor which consisted of a thin stainless foil (3.5cm$\times$13cm$\times$0.00254cm, 302 stainless steel shim), two electrodes, and a 20cm dia. $\times$30cm tall cylindrical Pyrex chamber sealed at both ends by aluminum flanges. The heating rate and time conditions were selected as $455^{\circ}C$ @ $1137^{\circ}C$ /s, $760^{\circ}C$ @ $950^{\circ}C$ /s and $977^{\circ}C$ @ $977^{\circ}C$/s. Tar samples after heating the soils were collected on the aluminum foil funnel and a glass filter paper (25mm dia. filter paper) The tar sample and remnant soil on the reactor were extracted with dichloromethane covering the filters, foils and soil by sonicating each in the waterbath for 10 minutes. The extractions were run on a HPLC. At the low peak temperature(about $455^{\circ}C$ @ $1137^{\circ}C$/s) the color of tar was "white", at the middle peak temperature (about 76$0^{\circ}C$ @ 95$0^{\circ}C$/s) the color of tar was "pink brown", at the high peak temperature (about 977$^{\circ}C$ @ 977$^{\circ}C$/s) the color of tar was "dark brown". Cyclopeta(cd)pyrene (CPEP) , which is an interesting species due to mutagenic effect on human cells, was detected in tar samples only above the middle peak temperature. This species was not detected at the low peak temperature. Six isomers of bipyrene were detected. Phenanthrene(C$_{14}$ $H_{10}$) and cyclopenta(def)phenanthrene(C$_{15}$ $H_{10}$) were also detected, but their content was very small relative to the other listed compounds.to the other listed compounds.

• Journal of Bio-Environment Control
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• v.23 no.4
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• pp.337-341
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• 2014

Due to the nature of the ambient air temperature in summer in korea, the growth of crops in greenhouse normally requires cooling and dehumidification. Even though various cooling and dehumidification methods have been presented, there are many obstacles to figure out in practical application such as excessive energy use, cost, and performance. To overcome this problem, the lab scale experiments using lithium bromide(LiBr) solution and cooling coil for dehumidification and cooling in greenhouses were performed. In this study, preliminary experiment of dehumidification and cooling for the greenhouse was done using LiBr solution as the dehumidifying materials, and cooling coil separately and then combined system was tested as well. Hot and humid air was dehumidified from 85% to 70% by passing through a pad soaked with LiBr, and cooled from 308K to 299K through the cooling coil. computational Fluid Dynamics(CFD) analysis and analytical solution were done for the change of air temperature by heat transfer. Simulation results showed that the final air temperature was calculated 299.7K and 299.9K respectively with the deviation of 0.7K comparing the experimental value having good agreement. From this result, LiBr solution with cooling coil system could be applicable in the greenhouse.

• Korean Journal of Agricultural Science
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• v.9 no.2
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• pp.540-545
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• 1982

An energy metabolism study was conducted with two commercial strains of meat-type chickens, Hubbard and Cobb, and two egg strains, Hy Line and Korean-bred Hanhyup 325. The heat production of growing chickens from each strain were measured by the use of an open-circuit gravimetric respiration calorimeter. The data obtained from this study were summarized as fallows. 1. The average body weight of 9-wk-old Hubbard broilers reared in battery cages was 2,570g/bird. The average body weights of 9-wk-old Hy Line chicks and Hanhyup 325 were 777 and 748g/bird, respectively. 2. At 3 weeks of age, the Hubbard broiler chicks consumed two times the feed consumed by Hy Line chicks (54.6g VS. 26.7g/bird/day). These values increased to 151g and 57.2g/bird/day, respectively, at 8 weeks of age, indicating that the difference in feed intake between meat and egg-type chicks tends to increase as they grow older. In terms of water consumption, the 5-wk-old Hubbard broiler chicks drank $226m{\ell}/bird/day$ as compared with $58m{\ell}$ by Hy Line chicks. These values increased to 282 and $70m{\ell}$, respectively, at 8 weeks of age. 3. The excreta outputs of Hubbard broilers and Hy Line chicks were 18.7 and 6.1g DM/bird/day at 4 weeks of age, and 41.5 and 10.0g DM/bird/day at 8 weeks of age, respectively. 4. The energy metabolizability of broiler chicks were 75.4~77.1% compared to 75.0~83.5% by egg-type chicks. 5. The respiratory quotient (RQ) was between 0.78 and 0.97. There seems to be no difference in RQ between meat and egg-type chicks. The RQ tended to decrease when feed intake was low and vice versa. 6. Both meat and egg-type chicks produced $83.1{\sim}123.1Kcal/kg^{\frac{3}{4}}B.W./day$. The considerably low value of $83Kcal/kg^{\frac{3}{4}}B.W./day$ was obtained when the chicks were off the feed under the stressful conditions. The high value of 123.1Kcal was obtained when the chicken chamber temperature rose to $27{\sim}34^{\circ}C$.

• Journal of radiological science and technology
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• v.26 no.4
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• pp.21-26
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• 2003

To evaluate the newly designed gastroduodenal coil catheter:in-vitro test. The coil catheter that we made in our laboratory was 150 cm. The coil that is made of stainless steel wire was composed 1.3 mm inner diameter and this coil spring was covered with heat-shrinkable polyethylene tube. To measure the length under fluorocopy, 8 radiopaque marks were attached at 5 cm, 10 cm, 11 cm, 12 cm, 13 cm, 14 cm, 15 cm, 20 cm apart from distal end of the catheter and 6, 2, 1 pores were made at 7 cm, 13 cm, 19 cm apart from the distal end. Radio-opacity and the amount of injected contrast was investigated in formerly used 5 Fr. vessel catheter, which is possible in measuring length, and newly designed coil catheter. Film density was tested for radio-opacity with autodensitometer. For measuring the volume of injected salin, the catheter was located in the acryl box(26 cm, 3 cm, 16 cm) that divided into 4 chambers. After injection 50 cc of contrast with autoinjector, the contrast's quantity in each chamber was measured with and without over the guide wire. Radio-opacity was 0.51 in 5 Fr. vessel catheter, 0.31 in newly made catheter. The amount of injected contrast was measured. In case of 5 Fr. vessel catheter, the amount was 99.5% from the distal part, there was no difference between with and without the guide wire. Otherwise, using a coil catheter, the pacentage the ejected saline was 1.17%, 18.8%, 41.8%, 38.2% from the distal part with the guide wire, 19.5%, 32.6%, 27.7%, 20.3% without the guide wire. Compare with formerly established catheter, this new coil catheter is easy to measure the length thanks to easy confirming under fluoroscopy and excellent in injecting contrast. Therefore, newly designed gastrointestinal catheter seems to be useful in gastrointestinal intervention procedure.

• 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.