• Proceedings of the KSME Conference
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• 2008.11a
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• pp.448-452
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• 2008

2-stroke marine diesel engine has generally one exhaust valve and three fuel injection nozzle which are key component for engine's performance and combustion. Fuel injection and exhaust valve driving system are driven by rotating of camshaft. Rotation of crank shaft drives the cam shaft through gear train that is composed of $3{\sim}4$ gear wheels. Gear column supporting the gear wheel has to bear against the dynamics forces by engine running as well as gearing forces. In this paper, structural analysis for engine structure and fatigue strength assessment of welded joint is shown. Repeatedly full cyclic simulation during one cycle is performed to investigate the structural behavior of engine. Fatigue analysis is carried out based on IIW using submodeling technique to obtain more detailed stress distribution.

• Transactions of the Korean Society of Automotive Engineers
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• v.12 no.5
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• pp.40-57
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• 2004

The effects of triple (pilot, main and after) injection on combustion and emission characteristics in a HSDI (High-Speed Direct Injection) diesel engine were investigated using a single-cylinder optical diesel engine equipped with a common-rail injection system. The pilot injection affected the spray and combustion evolution of the following main injection. It was found that the pilot injection reduced the ignition delay, which led to lowered NOx (Nitric Oxides) level, and increased IMEP (Indicated Mean Effective Pressure) due to slow combustion pace during an expansion stroke. The after-injection was shown to be effective in reducing PM (Particulate Matter) even when a small amount of fuel was added. The results suggest that a proper combination of individual injection strategy could bring about a good synergetic effect on engine performance and emission.

• Journal of the korean Society of Automotive Engineers
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• v.7 no.1
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• pp.35-42
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• 1985

This paper describes an experimental study of the effect of injection timing on the combustion characteristics in four stroke cycle diesel engine with direct injection type combustion chamber. The effect of injection timing and compression ratio of engine on the combustion characteristics are investigated. Experimental results of combustion characteristics in cylinder show that the combustion pressure and the rate of pressure rise decrease in accordance with the retard of fuel injection timing. It is observed that the rate of pressure rise in cylinder is increased an increase in the compression ratio of engine. The effect of the fuel injection timing on the frequency of cylinder pressure brings about the same trend of the maximum rate of pressure rise in cylinder.

• Journal of the korean Society of Automotive Engineers
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• v.7 no.2
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• pp.45-54
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• 1985

Recently, the problem of exhaust gas pollution is increasingly being aggravated by the active use of the Diesel engine. For the fuel-injection system which affects the composition of exhaust gas from the Bosch type single-hole nozzle in the Diesel engine, a mathematical model was set up to study pressure variations in the high pressure pipe, the injection rate, and the needle lift. The fundamental equations of the mathematical model have been solved by the Newton Raphson Method applying the Finite Diffrence Method. The effective stroke of the injection pump plunger due to a change in engine rpm was calculated by the measurement of Control Rack, Pinion, and Plunger sizes and by the use of Characteristic Curve of Governor. The computed results for the pressure variations in the high pressure pipe and needle lift at 800 rpm and 1000 rpm are in good agreement with experimental ones in general. By a developed program, the effects of other various parameters will by calculated for the performance of the fuel-injection system.

• International Journal of Precision Engineering and Manufacturing
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• v.8 no.1
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• pp.66-72
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• 2007

A computer code was developed to simulate the filling stage of an injection/compression molding process using a finite element method. The constitutive equation was the compressible Leonov model and the PVT relationship was assumed to follow the Tait equation. The flow-induced birefringence was related to the calculated flow stresses through the linear stress-optical law. Simulations of a disk under different processing conditions, including variations of the compression stroke and compression speed, were performed to determine their effects on the flow-induced birefringence. Simulated pressure traces were also compared to those obtained in conventional injection molding and with experimental data from the literature.

• The Journal of the Society of Stroke on Korean Medicine
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• v.15 no.1
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• pp.85-89
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• 2014

■ Objectives The purpose of this clinical study is to evaluate the effect of Traditional Korean Medicine(TKM) on a patient with abnormal eye movement. ■ Methods A patient with abnormal eye movement of limbs diagnosed with midbrain infarction was treated with herbal medication, acupuncture, moxa, and herbal medical injection. Then we evaluated the improvement by measuring range of eye movement. ■ Results Increase of range of eye movement and improvement of symptom of diplopia were observed after the TKM treatment. ■ Conclusion This study proved the effect of TKM treatment on abnormal eye movement due to midbrain infarction.

• Transactions of the Korean Society of Automotive Engineers
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• v.15 no.6
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• pp.1-8
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• 2007

Minimizing the cylinder wear and the consumption rate of cylinder oil in a large two-stroke marine diesel engine is of great economic importance. In Korea, authors first developed a motor-driven cylinder lubricator for a Wartsila Switzerland large two-stroke diesel engine. The characteristic of the developed product is that can control automatically the oil feed rate with a load fluctuation by the motor drive and the offset cam. For manufacturing the reliable and useful products, however, it is necessary to investigate further characteristics and to improve performances as a cylinder lubricator. In this study, the effects of pump motor speed, plunger stroke and cylinder back pressure on oil feed rate, maximum discharge and delivery pressures are experimentally investigated by using the electronically controlled quill injection system and distributer in the developed cylinder lubricator. It is found that the oil feed rates of electronic control and mechanical type quills with the in-cylinder back pressure are differently characterized by the role of accumulator, the viscous resistance of contact area, etc. It can be also shown that the maximum discharge pressure of the electronic control quill is lower than the mechanical type one but the maximum discharge pressure difference of two types decreased as plunger stroke is small, and the maximum delivery pressures of two types increased as plunger stroke, motor speed and back pressure are elevated but the maximum delivery pressure of mechanical type is higher than the one of electronic control type.

• Journal of Oriental Neuropsychiatry
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• v.32 no.3
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• pp.235-245
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• 2021

Objectives: To provide clinical evidence of pharmacopuncture treatment for post-stroke depression by reviewing randomized controlled trials on Traditional Chinese medicine pharmacopuncture for post-stroke depression. Methods: Randomized controlled trials on pharmacopuncture treatment for post-stroke depression were searched from the China National Knowledge Infrastructure (CNKI). Literature searches of English and Chinese databases were performed. Selected literature was assessed with the Jadad scale. Results: Twelve papers were selected from 20 studies. The following results were obtained: 1) Pharmacopuncture was used for post-stroke depression; 2) Dengzhan-Xixin was the most used injection medicine for post-stroke depression; 3) BaiHui (GV20) was the most used in pharmacopuncture treatment; 4) Based on the Hamilton Depression Rating Scale (HAMD), it was confirmed that all studies using pharmacopunture had significant efficacy. Conclusions: For the treatment of post-stroke depression, Dengzhans-Xixin was commonly used as an injectable medication. Additional research studies on pharmacopuncture including its practical use are needed.

• The Journal of the Society of Stroke on Korean Medicine
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• v.16 no.1
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• pp.11-18
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• 2015

■ Objectives The purpose of this clinical study is to evaluate the effect of Traditional Korean Medicine(TKM) on a patient with tremor. ■ Methods A patient with tremor of one side hand diagnosed with Parkinson's disease was treated with herbal medication, acupuncture, electro-acupuncture(EA), and herbal medical injection. Then we evaluated the improvement by Unified Parkinson's Disease Rating Scale(UPDRS), Parkinson's disease Quality of Life(PDQL) and Visual Analog Scale(VAS). ■ Results Decrease of UPDRS, VAS score and improvement of PDQL score were observed after the TKM treatment. ■ Conclusion This study proved the effect of TKM treatment on tremor due to Parkinson's disease.

• The Journal of the Society of Stroke on Korean Medicine
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• v.16 no.1
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• pp.81-88
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• 2015

■ Objectives The purpose of this clinical study is to evaluate the effect of Traditional Korean Medicine(KM) on a patient with Tolosa-Hunt syndrome. ■ Methods We treated a 58 years old male patien t with Tolosa-Hunt syndrome who had several clinical symptoms such as ocular pain, limitaion of ocular movement and unilateral ptosis. We used herbal medication, acupuncture, electro-acupuncture(EA), cupping, moxibustion, bee-venom injection. Then we evaluated the improvement by Numerical Rating scale(NRS), Distance of eye opening and ratio of pupil movement. ■ Results We demonstrated the decrease of pain score and improvement of equal ocular movement(EOM) and ptosis after the KM treatment. ■ Conclusion This study proved the effect of KM treatment on Tolosa-Hunt syndrome. It could cooperative treatment would be more effective than mono treatment of western medicine.