• Journal of ILASS-Korea
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• v.11 no.3
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• pp.140-146
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• 2006

The objective of this work is to analyze the atomization and evaporation characteristics of dimethyl ether(DME) fuel for the application of HCCI diesel engine. In order to investigate the spray behavior of DME fuel, the macroscopic and microscopic characteristics were investigated in terms of spray development, spray tip penetration, impingement time, SMD, and axial mean velocity under the various injection timing and ambient conditions. For the illumination of spray, the spray visualization system was composed of a Nd:YAG laser and an ICCD camera and laser-sheet method was used. The atomization characteristics of DME fuel are analyzed by using phase Doppler particle analyzer (PDPA) system It was reveal that the spray development of DME is slower and rapidly disappeared as elapsed time after start of injection at the same injection duration. The impingement timing of diesel fuel was fester than that of DME fuel. The comparison of spray atomization characteristics in both fuels shows that diesel fuel has a large SMD value that DME.

• Toxicological Research
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• v.20 no.4
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• pp.375-380
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• 2004

The toxicity of CKD-602 was investigated at doses of 0, 3, 9, and 27 mg/kg in rats, by administering the same total dose over 24-hr continuous infusion or bolus injection. CKD-602 treatment caused gastrointestinal symptoms such as diarrhea, soft stool, and soiled perineal region. It also decreased body weight at doses of 9 and 27 mg/kg in a dose-dependant manner. At 3 mg/ kg, clinical signs and body weight decrease were more severe in the infusion group than in the bolus group. In the bolus group, mortalities were 0/8, 0/8, 1/8, and 3/8 at 0, 3, 9, and 27 mg/kg, respectively, whereas those were 0/8, 1/8, 8/8, and 8/8 in the infusion group. $LD_{50}$ values were 36.25 mg/kg for bolus and 3.50 mg/kg for infusion, respectively. This finding indicates that the toxic potency of CKD-602 by continuous infusion is about 10 times higher than by bolus injection. Our findings suggest that the toxic effects of CKD-602 are dependant upon the duration of intravenous administration.

• Toxicological Research
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• v.20 no.4
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• pp.381-389
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• 2004

The toxicity of CKD-602 was investigated at doses of 3, 9, and 27 mg/kg in rats, when the same total dose of CKD-602 was administered over 24 hr-continuous infusion or bolus injection. At 3 and 9 mg/kg, the 24-hr infusion group showed a more decreased WBC count on day 3, compared with the bolus group. Administration of CKD-602 caused more toxic effects such as the significant decreases of RBC counts, hematocrit, hemoglobin, and platelet count on day 7 post-administarion in the 24-hr infusion group than in the bolus group. Administration of CKD-602 also caused histopathological changes such as extramedullary hemopoiesis of liver and spleen, hyperplasia of femoral bone marrow, and caecal dilation. These toxic effects were more severe in the 24-hr infusion group than in the bolus injection group, indicating that the toxicity of CKD-602 may be dependant upon the duration of administration.

• 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.

• Transactions of the Korean Society of Pressure Vessels and Piping
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• v.7 no.1
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• pp.1-8
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• 2011

Advanced SITs of the evolutionary PWRs have the advantage that they can passively control the ECC water discharge flow rate. Thus, the LPSI pumps can be eliminated from the safety injection system owing to the benefit of the advanced SITs. In the present study, a passive sealing plate was designed in order to overcome the shortcoming of the advanced SITs, i.e., the early nitrogen discharge through the stand pipe. The operating principle of the sealing plate depends only on the natural phenomena of buoyancy and gravity. The performance of the sealing plate was evaluated using the VAPER test facility, equipped with a full-scale SIT. It was verified that the passive sealing plate effectively prevented the air discharge during the entire duration of the ECC water discharge. Also, the major performance parameters of the advanced SIT were not changed with the installation of the sealing plate.

• International Journal of Automotive Technology
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• v.2 no.2
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• pp.39-45
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• 2001

Hydrogen is seen as one of the important energy vectors of the next century. Hydrogen as a renewable energy source, provides the potential for a sustainable development particularly in the transportation sector. Hydrogen driven vehicles reduce both local as well as global emissions. The laboratory of transporttechnology (University of Gent) converted a GM/Crusader V-8 engine for hydrogen use. Once the engine is optimised, it will be built in a low-floor midsize hydrogen city bus for public demonstration. For a complete control of the combustion process and to increase the resistance to backfire (explosion of the air-fuel mixture in the inlet manifold), a sequential timed multipoint injection of hydrogen and an electronic management system is chosen. The results as a function of the engine parameters (ignition timing. injection timing and duration, injection pressure) we given. Special focus is given to topics related to the use of hydrogen as a fuel: ignition characteristics (importance of electrode distance), quality of the lubricating oil (crankcase gases with high contents of hydrogen), oxygen sensors (very lean operating conditions), noise reduction (configuration and length of inlet pipes). The advantages and disadvantages of a power regulation only by the air to fuel ratio (as for diesel engines) against a throttle regulation (normal gasoline or gas regulation) are examined. Finally the goals of the development of the engine are reached: power output of 90 kW, torque of 300 Nm, extremely low emission levels and backfire-safe operation.

• Tuberculosis and Respiratory Diseases
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• v.72 no.5
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• pp.448-451
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• 2012

Invasive pulmonary aspergillosis (IPA) has emerged as a severe infection in patients with immunocompromised hosts. However, recently, several IPA cases, without an apparent predisposition to immunodeficiency, has been reported. A 72-year-old woman was admitted for evaluation of general weakness and poor oral intake. She reported no medical history, except for intraarticular injection of a corticosteroid for joint pain for the duration of two months. A chest radiography revealed multiple cavitary nodules in both lungs. Examination of specimens, obtained by percutaneous needle biopsy, led to a diagnosis of invasive aspergillosis. Brain magnetic resonance imagining revealed numerous peripheral thin enhancing cystic nodules in both cerebral hemispheres. We initiated intravenous administration of amphotercin B. However, the patient died after nine days. Here, we report an invasive aspergillosis case, which involves the lungs and brain after a short period of steroid injection.

• The Korea Journal of Herbology
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• v.35 no.6
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• pp.29-34
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• 2020

Objectives : Gyejigamchoyonggolmoryeo-tang (GT, Guizhigancaolonggumulitang in Chinese) is a herbal medicine to be prescribed for insomnia caused by anxiety induced by Heart-Heat and elevated Liver-Yang. In the present study, the onset time (sleep latency) and the duration time of sleep were measured to find out the sleep inducing effects of GT. The expression of c-fos immunohistochemistry was also measured at the ventrolateral preoptic area (VLPO) and tuberomammillary nucleus (TMN) site in brain. Methods : The onset time (sleep latency) and the duration time of sleep were measured 30 minutes after thiopental sodium injection. Thereafter, brain tissue was obtained and c-fos immunohistochemistry was performed on the VLPO and TMN sites. Results : GT statistically significantly reduced the sleep latency required to enter sleep, and significantly increased sleep duration time. GT significantly increased the number of c-fos immunohistochemical staining-positive cells in the sleep-inducing center (VLPO), whereas GT significantly decreased the number of c-fos immunohistochemical staining-positive cells in the arousal center (TMN). Conclusions : It could be concluded that the GT shortened the sleep latency and increased the duration time for sleep induced by thiopental sodium. And it was confirmed that the mechanism was to stimulate the sleep-inducing center (VLPO) and suppress the arousal center (TMN) in the brain. The results of this study are considered to be useful as scientific evidence that can be used clinically for the treatment of insomnia caused by anxiety.

• Journal of Korean Medicine Rehabilitation
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• v.15 no.1
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• pp.89-98
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• 2005

Objectives : This study was to investigate the effects of Clematidis Radix on Proteoglycan(PG) degradation by measuring of body weight, Glycosaminoglycan(GAG), Interleukin-$1{\beta}$($IL-1{\beta}$) in synovial fluid, and PG content of articular cartilage of femur in collagenase-induced arthritis in rats. Methods : Arthritis was induced by injection of collagenase(0.1 ml) into knee joint of rats. Arthritic rats were divided into control(n=8) and treated(n=8) group. Control group was taken normal saline for 15 days and treated group was taken extracts of Clematidis Radix for same duration. Normal group(n=8) was injected with normal saline and was taken normal saline for 15 days. Body weight was measured at 0, 10, 15 days after injection. GAG, $IL-1{\beta}$ in synovial fluid were measured with ELISA kit at 15 days after injection. PG content of articular cartilage of femur, represented by safranine O staining, was measured at 15 days after injection. Histopathological study on the articular cartilage of knee joint was investigated at 15 days after injection. Results : Body weight, PG of treated group, taken Clematidis Radix, were significantly increased, and GAG was significantly decreased compared with control group. But $IL-1{\beta}$ was not significantly decreased. Conclusions : On the basis of these results, we concluded that Clematidis Radix has inhibiting effects on the proteoglycan degradation in collagenase-induced rat osteoarthritis model.

• Archives of Plastic Surgery
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• v.32 no.3
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• pp.311-313
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• 2005

Generally, many Asian women tend to dislike the square jaw, as they believe it makes the face look wider, giving a stubborn and strong impression. Contouring of the mandible is therefore a relatively common aesthetic procedure among Asians. These days, the use of botulinum toxin for contouring of the lower face offer simple alternative to surgery. Motor point, which is the site over a muscle where its contraction may be elicited by a minimal intensity short duration electrical stimulus, is the optimal injection point of botulinum toxin. Study was undertaken to identify the location of motor point of the masseter muscle and the skin surface landmark. First, the thickest point of the masseter muscle was inspected through palpation and inspection by 3 different individual plastic surgeons and then compound muscle action potentials(CMAPs) of masseter muscle in 15 health volunteers were recorded using EMG. For the localization of the measured points, line between lateral canthus to the mandibular angle was used. Location of motor points were mapped to skin surface from lateral canthus in a percentage of the distance along the landmark line and in distance in millimeters. The clinical injection point was located at 71.69 percentile and 7.3 mm of the landmark line. The motor point test was located at 72.54 percentile and 7.1 mm of the landmark line. The depth of motor point was 16mm. There was no statistically significant difference between the clinical injection point and the motor point. We conclude that surface mapping of motor point of the masseter muscle would increase accessibility and accuracy in botulinum toxin injection for contouring of the lower face.