• Journal of ILASS-Korea
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• v.12 no.2
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• pp.94-100
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• 2007

The liquid phase LPG injection (LPLi) system (the third generation technology) has been considered as one of the next generation fuel supply systems for LPG vehicles, since it has a very strong potential to accomplish the higher power, higher efficiency, and lower emission characteristics than the mixer type (the second generation technology) fuel supply system. To investigate the characteristics of LPG residue in liquid phase LPG injection system, various rubbers in LPG fuel system were reacted with LPG fuels during 3 months. The experimental results showed that the residue of a cover rubber in a fuel pump after test increased 10 times higher than that before test. Furthermore, the amount of sulfur, nitrogen species which are considered as main sources in deposit formation in the LPLi fuel injector were also found to be higher than that in original LPG fuel. And rubber properties of fuel pump cover were decreased after reaction test compared with those of the original rubber. Therefore, the rubber for fuel pump cover is not suitable for a proper material in LPLi fuel system. And these results can provide more information if a motor company shares the data of core rubber parts in field test LPLi vehicles.

• Transactions of the Korean Society of Mechanical Engineers
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• v.19 no.2
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• pp.322-329
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• 1995

Series of experimental work was performed to mold tensile specimens by using the injection molding machine Mold temperature, melt temperature and packing time were chosen as processing parameters for studying the effects of those conditions on the linear shrinkage of final product. Here, each processing variable was decided from the numerical simulation and resin manufacturer's suggested value. The effects of molding conditions on the linear shrinkage in flow direction of the resin were analyzed by measuring the parts 2, 10, 30 and 60 days after molding. As a result, the linear shrinkage increased with the higher mold and melt temperature, and the change of mold temperature has shown more influence. The linear shrinkage of polypropylene has been found to progress up to 30 day with the lapse of the time, and the amount of the linear shrinkage has shown to be between 2.14% and 2.75%. In addition, the effects of packing pressure on the weight has shown to be extremely significant up to freezing time, and proper packing time of the tensile specimen has been found to be 2.0 seconds.

• Tuberculosis and Respiratory Diseases
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• v.41 no.1
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• pp.42-46
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• 1994

Pulmonary Aspergillomas usually arise from proliferation of Aspergillus in preexisting parenchymal cavities.202 college students (99 men, 103 women) aged 18 to 26 years. Fasting blood samples were. The most common symptom in this disorder is hemoptysis, which may be minimal in amount or it may be massive & life threatening. The optimum therapy for pulmonary aspergilloma is controversial. The major options available include surgical resection of the lesion, a number of medical therapies, or simple observation of the patient for a time. Surgery is the most effective treatment but it is limited to some patient because most patients have underlying pulmonary disease. Thus the various form of medical therapy was available with successful result. The authors present a case of percutaneous intracavitary amphoterician B injection for the treatment of pulmonary aspergilloma & its successful effect for the repetitive hemoptysis.

• Journal of the Korean Arthroscopy Society
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• v.2 no.2
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• pp.119-123
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• 1998

In order to obtain a good result in Arthroscopic ACL Reconstruction by immediate postoperative physical therapy, sufficient analgesia was needed. This study analyzes the analgesic effect of the intra-articular injection with ketorolac, Morphine together with bupivacaine in 80 male patients who had Arthroscopic ACL Reconstruction. On completion of the surgery under spinal anesthesia, the knee was injected with 30ml of 0.25% bupivacaine. Each of the study group received ketorolac and/or morphine, either through parenteral or intra-articular. Total amount of the drug used by Patient Controlled Analgesia(PCA) and Visual Analgesia Scale(VAS) for pain were measured and analyzed. The group which received intra-articular ketorolac or Morphine had a better analgesic effect than other group which received none. The group which received both did not do better in analgesic effect. Intra-articular infusion with either ketorolac or Morphine improved postoperative analgesia in Arthroscopic ACL Reconstruction surgery. However, combined injection did not offer more advantage.

• Transactions of the Korean Society of Mechanical Engineers B
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• v.26 no.12
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• pp.1756-1762
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• 2002

To effectively meet current regulations on the exhaust emissions of diesel engine required to control the deterioration of air pollution in the whole world, this study is to investigate the effects of water induction through the air intake system on the characteristics of combustion and exhaust emissions in IDI diesel engine. A method fur supplying water through the air intake system to reduce the exhaust emissions has been considered with other methods such as water introduction in the form of water-in-fuel emulsion or water injection directly into the combustion chamber, but it has not been studied about the effects of water on the combustion concepts and the characteristics of exhaust emissions in detail until now. In this study, the formation of NOx was significantly suppressed by decreasing the gas peak temperature during the initial combustion process because the water play a role as a heat sink during evaporating in the combustion chamber, but the smoke was slightly increased by increasing water amount.

• The KSFM Journal of Fluid Machinery
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• v.15 no.6
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• pp.18-24
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• 2012

This study simulated the operation of a steam injected gas turbine combined heat and power (CHP) system. A full off-design analysis was carried out to examine the change in the turbine blade temperature caused by steam injection. The prediction of turbine blade temperature was performed for the operating modes suggested in the previous study where the limitation of compressor surge margin reduction was analyzed in the steam injected gas turbine. It was found that both the fully injected and partially injected operations suggested in the previous study would cause the blade temperature to exceed that of the pure CHP operation and the under-firing operation would provide too low blade temperature. An optimal operation was proposed where both the turbine inlet temperature and the injection amount were modulated to keep both the reference turbine blade temperature and the minimum compressor surge margin. The modulation was intended to maintain a stable compressor operation and turbine life. It was shown that the optimal operation would provide a larger power output than the under-firing operation and a higher efficiency than the original partially injected operation.

• Korean Journal of Veterinary Research
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• v.13 no.1
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• pp.57-62
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• 1973

The antibiotics are usually used for the medical treatments or the other purpose for cow and almost of them are transfered to milk. Moreover a serious problems on public health are caused by misuse or overuse of antibiotics. These studies were conducted to determine the rise and fall of antibiotics in the raw milk which is milked from the cow treated with antibiotics. The number of samples examined were 500 which were taken from 36 cows, and the antibiotics in milk were detected by cylinder plate assay method. The results were as follows: 1) When penicillin, chloramphenycol and streptomycin were infused into a udder, they were detected up to the period of 84 hours, 36 hours and 60 hours after injection in the milk from the same udder, however in the milk from the other udder streptomycin was not detected but penicillin and chloramphenycol were detected up to 72 hours and 24 hours after injection. When streptomycin and penicillin were injected intramusculary, streptomycin was not detected in the milk but penicillin was detected up to 60 hours after injcetion. 2) When penicillin, streptomycin and chloramphenycol were infused into the udder, the lesser amount of milk was produced, the more antibiotics were detected in the milk. 3) It is necessary policy for the public health to inhibit to be sold the milk up to 3 days or more after the injection on antibiotics or to add food blue to mastitis drugs.

• Transactions of the Korean Society of Automotive Engineers
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• v.17 no.3
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• pp.142-148
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• 2009

The direct injection(DI) diesel engine has become a prime candidate for future transportation needs because of its high thermal efficiency. However, nitrogen oxides(NOx) increase in the local high temperature regions and particulate matter (PM) increases in the diffusion flame region within diesel combustion. Therefore, the demand for developing a suitable after treatment device has been increased. NOx absorbing catalysts are based on the concept of NOx storage and release making it possible to reduce NOx emission in net oxidizing gas conditions. This De-NOx system, called the LNT(Lean NOx Trap) catalyst, absorbs NOx in lean exhaust gas conditions and release it in rich conditions. This technology can give high NOx conversion efficiency, but the right amount of reducing agent should be supplied into the catalytic converter at the right time. In this research, a performance characteristics of LNT with a hydrogen enriched gas as a reductant was examined and strategies of controlling the injection and rich exhaust gas condition were studied. The NOx reduction efficiency is closely connected to the injection timing and duration of reductant. LNT can reduce NOx efficiently with only 1 % fuel penalty.

• Journal of Korean Society for Atmospheric Environment
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• v.12 no.3
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• pp.315-322
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• 1996

Recently, hospital acquired infections have an increase interest as a public problems, which are caused of indoor pollutants in hospital. Microorganisms, ethylene oxide, formaldehyde, and anesthetic gases are main hazardous pollutants in hospital. The possible pathways of the infection are a respiratory channel as well as a blood channel. The blood channel is concerned since these pollutants might be dissolved into the Ringer's solution. The objective of this research was to evaluate the removal efficiencies of adsorption trap for formaldehyde and microorganisms as indoor pollutants which permeated into the Ringer's solution. Dissolved formaldehyde in the solution was increased with the injection dose time. The amount of dissolved formaldehyde was 67.5 $\pm$ 9.5% in Ringer's solution when injection dose time was controlled about 7hrs. An adsorption trap was designed for preventing formaldehyde and microorganisms to be permeated into Ringer's solution. The adsorption trap was packed with 0.4g of active carbon (60/80 mesh) in a sterilized plastic tube (7.79 cm length, 0.46 cm i.d.) and both ends were packed with glass wool. Devised infusion set equipped with the adsorption trap showed 99.9% of removal efficiency for formaldehyde. Microorganism numbers detected on sterilized water for injection and 5% dextrose infusion used in the hospital were 2,695 $\times 10^3$ cells/l and 4,190 $\times 10^3$ cells/l, respectively. Removal efficiency by the adsorption trap was 92.3 $\pm$ 8.5% as for microorgnisms.

• Journal of Powder Materials
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• v.9 no.4
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• pp.235-244
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• 2002

The effects of residual impurities on solid state sintering of the powder injection molded (PIMed) W-15wt%Cu nanocomposite powder were investigated. The W-Cu nanocomposite powder was produced by the mech-ano-chemical process consisting of high energy ball-milling and hydrogen reduction of W blue powder-cuO mixture. Solid state sintering of the powder compacts was conducted at $1050^{\circ}C$ for 2~10 h in hydrogen atmosphere. The den-sification of PIM specimen was slightly larger than that of PM(conventional PM specimen), being due to fast coalescence of aggregate in the PIM. The only difference between PIM and PM specimens was the amount of residual impurities. The carbon as a strong reduction agent effectively reduced residual W oxide in the PIM specimen. The $H_2O$ formed by $H_2$ reduction of oxide disintegrated W-Cu aggregates during removal process, on the contrary to this, micropore volume rapidly decreased due to coalescence of the disintegrated W-Cu aggregates during evolution of CO.It can be concluded that the higher densification was due to the earlier occurred Cu phase spreading that was induced by effective removal of residual oxides by carbon.