출혈성 쇽, 뇌증에 대한 임상적 고찰

박정권(Jeong Kwon Park),배원정(Won Jeong Bae),임병학(Byung Hak Lim),강임주(Im Ju Kang) 대한소아신경학회 1995 대한소아신경학회지 Vol.2 No.2

Five cases of hemorrhagic shock and encephalopathy who were diagnosed in the Department of pediatrics, Taegu Fatima Hospital form January 1993 to October 1994 were reviewed. The results were as follows: 1. The onset of symptoms was between 6 months and 12years of age. 4 cases were male and 1 case was female. 2. Prodromal illness was noticed in 4 cases, one case was epilepsy patient and was medicated Valproic acid for several years. 3. The initial symptoms were seizure in 5 cases, shock in 3 cases, acute respiratory failure in 2 cases. 4. Hematologic findings were disseminated intravascular coagulation, hepatic dysfunction, renal dysfunction in all cases. The three survivors showed most deranged hematologic findings within 2 days after onset and rapidly normalized within 8 days after onset. 5. Brain MRI. CT of 3 survivors showed normal findings. 6. Two of the cases died, three of the survivors are neurologically damaged.

연관규칙을 활용한 상품 구매 패턴분석에 관한 연구

정용규,박정권,이정찬,최은영,Jung, Yong Gyu,Park, Jeong Kwon,Lee, Jeong Chan,Choi, Eun Young 서비스사이언스학회 2012 서비스연구 Vol.2 No.1

기업의 데이터베이스 규모는 계속 증가되고 있는 추세이다. 이런 대량의 데이터베이스에서 유용한 정보를 얻는 데이터마이닝은 다양한 예측기법이나 차이점의 분석을 통하여 매출의 증대나, 비용 절감 등의 효과를 줄 수 있다. 분석방법에는 정보의 다양한 분류기법 또한 다양한 각도나 영역의 관점을 통하여 분석할 수 있다. 연관규칙과 패턴의 분석은 대량의 데이터베이스에서 유용한 정보를 효과적으로 분석할 수 있다. 본 논문에서는 쇼핑몰의 상품을 데이터마이닝 분석 기법중의 하나인 연관규칙을 활용하여 분석하였다. 이를 통하여 기존상품 분류 및 분석에 따른 고객의 구매패턴을 분석하고, 전략적 마케팅 수립을 통해 접근할 수 있는 데이터마이닝 분석에 관한 사례를 연구하였다. It is growing in size of database in companies. This caused to develope data mining techniques to predictive information from the large database. Costs and other effects can give variety of sales exploding through the analysis of the differences. Analysis of the various classification techniques, various angle can be analyzed point of view of the area information. The analysis of rules and patterns associated with a large amount of useful information from the database can be analyzed effectively. Goods store were analyzed using association rules, one of the data mining analysis techniques. Through this type of existing products according to analyze customer buying patterns, data mining has been studied to establish strategic marketing analysis.

커먼레일 연료분사 시스템을 장착한 경량 DME 트럭의 연구 및 개발

정수진,전문수,박정권,Jeong, Soo-Jin,Chon, Mun Soo,Park, Jung-Kwon 한국교통대학교 융복합기술연구소 2012 융ㆍ복합기술연구소 논문집 Vol.2 No.1

In this study, the trucks(2.9-liter) have been developed to use DME as fuel, and performance test of the vehicle's DME engine, power, emissions, fuel economy and vehicle aspects was conducted. For experiments, the fuel system(common-rail injectors and high-pressure pump included) and the engine control logic was developed, and ECU mapping was performed. As a result, the rail pressure from 40MPa to approximately 65% increase compared to the base injector has been confirmed that. Also, the pump discharge flow is 15.5 kg/h when the fuel rail pressure is 400rpm(40 MPa), and the pump discharge flow is 92.1 kg/h when the fuel rail pressure is 2,000rpm(40MPa). The maximum value of full-load torque capability is 25.5kgfm(based on 2,000rpm), and more than 90% compared to the level of the diesel engine were obtained. The DME vehicle was developed in this study, 120 km/h can drive to the stable, and calculated in accordance with the carbon-balance method of fuel consumptions is 5.7 km/L.

커먼레일 연료시스템에서의 DME 분무 특성에 대한 실험과 해석적 연구

정수진(Soo-Jin Jeong),박정권(Jung-Kwon Park),이상인(Sang-In Lee),임옥택(Ock-Taeck Lim) 대한기계학회 2012 大韓機械學會論文集B Vol.36 No.12

본 논문에서는 노즐홀 직경을 확대하여 유량을 증가시킨 DME 인젝터의 가시화 실험과 분무 해석을 수행하였다. 해석의 신뢰성을 확보하기 위하여 가시화 실험과 분무해석을 비교하였고, 실엔진 모사 조건에서 분무 해석을 수행하여 DME의 거동을 예측하였다. 분사 압력과 분위기 압력이 각각 35MPa 및 5MPa인 경우 가시화 실험과 분무 해석의 도달거리는 3.57%의 차이를 나타내었다. 실엔진 모사 해석의 경우, 완전하게 발달된 DME의 분무 도달거리는 분위기 온도와 압력의 비가 300K/MPa에서 42mm로 최대를 나타내었고, 300K/MPa미만의 영역에서 DME의 분무는 분위기 압력, 300K/MPa초과의 영역에서는 분위기 온도의 영향이 지배적임을 확인하였다. Spray visualization and computer simulation of a DME injector have been conducted to investigate the enlarged injection hole diameter effect. To increase the reliability of the computational result, simulation results have been compared with the visualization test results, and the behaviors of a DME spray under various high-pressure and -temperature conditions have been computed. This study shows a discrepancy of 3.57% between the experimental and the computational results of penetration length for an injection pressure of 35 MPa and ambient pressure of 5 MPa. When simulating the engine conditions, the maximum penetration length of a fully developed DME spray is 42 mm when the temperature to pressure ratio is 300 K/MPa. The DME spray behavior is dominantly affected by the ambient pressure under the condition that the ratio is less than 300 K/MPa, and by the ambient temperature under the condition that the ratio is more than 300 K/MPa.

커먼레일 연료분사 시스템을 장착한 2.9 리터급 경량 DME 트럭의 연구 및 개발

정수진(Soo-Jin Jeong),박정권(Jung-Kwon Park),오세두(Se-Doo Oh),이기수(Gee-Soo Lee),임옥택(Lee Ock-Taek Lim),표영덕(Young-Dug Pyo) 한국자동차공학회 2012 한국 자동차공학회논문집 Vol.20 No.6

In this study, the trucks(2.9-liter) have been developed to use DME as fuel, and performance test of the vehicles DME engine, power, emissions, fuel economy and vehicle aspects was conducted. For experiments, the fuel system(common-rail injectors and high-pressure pump included) and the engine control logic was developed, and ECU mapping was performed. As a result, the rail pressure from 40MPa to approximately 65% increase compared to the base injector has been confirmed that. Also, the pump discharge flow is 15.5 kg/h when the fuel rail pressure is 400rpm(40MPa), and the pump discharge flow is 92.1 kg/h when the fuel rail pressure is 2,000rpm(40MPa). The maximum value of full-load torque capability is 25.5 kgfm(based on 2,000 rpm), and more than 90% compared to the level of the diesel engine were obtained. The DME vehicle was developed in this study, 120 km/h can drive to the stable, and calculated in accordance with the carbon-balance method of fuel consumptions is 5.7 km/L.

공동현상을 고려한 커먼레일용 고압 DME 인젝터 노즐의 최적 설계 연구

정수진(Soo-Jin Jeong),박정권(Jung-Kwon Park),이상인(Sang-In Lee) 한국자동차공학회 2013 한국 자동차공학회논문집 Vol.21 No.1

DME (Di-Methyl Ether) is synthetic product that is produced through dehydration of methanol or a direct synthesis from syngas. And it is able to save fossil fuel and reduce pollutants of emission such as PM and CO2. In spite of its advantages it is difficult to design DME fuelled engine system because DME fuel may cause to severely generate cavitation and corrosion in fuel delivery system due to physical properties of DME. Therefore, in this study three-dimensional internal flow characteristics with consideration of cavitation were predicted in the DME injector using diesel and DME fuel. Moving grid technique was employed to describe needle motion and 1-D hydraulic simulation of injector was also simulated to obtain transient needle motion profiles. The results of simulation show that cavitations was generated at the inlet of nozzle near high velocity region both diesel and DME. And mass flow rate of DME is reduced by 4.73% compared to that of diesel at maximum valve lift because cavitation region of DME is much more larger. To increase flow rate of DME injector, internal flow simulation has been conducted to investigate the nozzle hole inner R-cut effect. The flow rates of diesel and DME increase as R-cut increases, and flow coefficient of DME fuel injector was increased by 6.3% on average compared with diesel fuelled injector. Finally, optimum shape of DME injector nozzle is suggested through the comparison of flow coefficient with variation of nozzle hole inner R-cut.

연비 개선 및 CO₂ 저감을 위한 승용디젤 차량의 클러치타입 워터펌프 적용에 따른 실험적 연구

정수진(Soo-Jin Jeong),박정권(Jung-Kwon Park),오창복(Chang-boke Oh),조용석(Yong-seok Cho) 한국자동차공학회 2012 한국 자동차공학회논문집 Vol.20 No.2

A typical cooling system of an engine relies on a water pump that circulates the coolant through the system. The pump is typically driven by the crankshaft through a mechanical link with engine starting. In order to reduce the friction and warm-up time of an engine, the clutch-type water pump (CWP) was applied in 2.0 liter diesel vehicle. The clutch-type water pump can force cooling water to supply into an engine by the operation of an electromagnetic clutch equipped as the inner part of pump system. The onset of CWP is decided by temperature of cooling water and engine oil. And, the control logic for an optimal operation of the clutch-type water pump was developed and applied in engine and vehicle tests. In this study, the warm-up time was measured with the conventional water pump and clutch-type water pump in engine tests. And the emission and the fuel consumption were evaluated under NEDC mode in vehicle tests. Also, tests were carried out for the various temperature conditions starting the operation of CWP. From the results of the study, the application of CWP can improve the fuel consumption and CO₂ reduction by about 3%.

Urea-SCR 분사시스템의 DeNOx 저감 성능 향상과 NH₃ 슬립 저감을 위한 모델 기반 제어알고리즘 개발 및 구현

정수진(Soo-Jin Jeong),김우승(Woo-Seung Kim),박정권(Jung-Kwon Park),이호길(Ho-Kil Lee),오세두(Se-Doo Oh) 한국자동차공학회 2012 한국 자동차공학회논문집 Vol.20 No.1

The selective catalytic reduction (SCR) system is a highly-effective aftertreatment device for NOx reduction of diesel engines. Generally, the ammonia (NH3) was generated from reaction mechanism of SCR in the SCR system using the liquid urea as the reluctant. Therefore, the precise urea dosing control is a very important key for NOx and NH₃ slip reduction in the SCR system. This paper investigated NOx and NH₃ emission characteristics of urea-SCR dosing system based on model-based control algorithm in order to reduce NOx. In the map-based control algorithm, target amount of urea solution was determined by mass flow rate of exhaust gas obtained from engine rpm, torque and O₂ for feed-back control NOx concentration should be measured by NOx sensor. Moreover, this algorithm can not estimate NH₃ absorbed on the catalyst. Hence, the urea injection can be too rich or too lean. In this study, the model-based control algorithm was developed and evaluated on the numerical model describing physical and chemical phenomena in SCR system. One channel thermo-fluid model coupled with finely tuned chemical reaction model was applied to this control algorithm. The vehicle test was carried out by using map-based and model-based control algorithms in the NEDC mode in order to evaluate the performance of the model based control algorithm.

커먼레일 DME 연료시스템을 적용한 상용 DME 엔진 개발

오세두(Se-Doo Oh),박정권(Jung-Kwon Park),이호길(Ho-Kil Lee),이기수(Gee-Soo Lee),정수진(Soo-Jin Jeong) 한국자동차공학회 2011 한국자동차공학회 부문종합 학술대회 Vol.2011 No.5

Di-methyl ether (DME) has attracted a iot of interest as the upcoming alternative fuel that can satisfy the saving of fossil energy and the reduction of air pollutants and the greenhouse gas such as CO₂. DME as an automotive fuel can be produced on similar levels of diesel oil prices. And it is reported that the DME engine shows the equal emission performance with a gasoline engine and the equal thermal efficiency with a diesel engine. In this study, the DME prototype engine was made with 3-liter diesel engine of a common-rail injection system. This engine has the high pressure fuel pump and the injectors for the DME fuel. The power performances and the emission characteristics of its engine were investigated with an universal ECU system. The high pressure pump is an eccentric type with 2-plungers, and the high pressure injector is designed by the nozzle flow analysis. The universal ECU system includes the separate injector driver. And injection rate, injection pressure, injection timing, injection duration, multi injection and EGR rate can be controlled by this system. The performance of an universal ECU system was confirmed comparing with that of the base diesel engine. DME engine performance was measured. And the emission characteristics of its engine were evaluated and in various operating conditions.

DME 커먼레일 자동차의 개발 및 전망

정수진(Soo-Jin Jeong),박정권(Jung-Kwon Park) 한국자동차공학회 2012 오토저널 Vol.34 No.8