• 제어로봇시스템학회:학술대회논문집
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• 제어로봇시스템학회 2002년도 ICCAS
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• pp.43.2-43
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• 2002

$\textbullet$ A PC can control the fixed number of motors because the number of slots is limited. $\textbullet$ We propose a distributed motion controller using CAN. $\textbullet$ TMS320F243 of TI Which is a DSP with embedded CAN-module was used as the main processor. $\textbullet$ The command from GUI is transmitted to each motion controller through CAN-bus $\textbullet$ CAN communications may occur at a maximum recommended rate of 1Mbit/sec. $\textbullet$ The user can control more motors easily by connecting to the CAN network which has the CAN receive. $\textbullet$ This distributed motion controller may be used usefully in factory automation or an unmanned factory.

• 한국소성가공학회:학술대회논문집
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• 한국소성가공학회 1999년도 춘계학술대회논문집
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• pp.111-114
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• 1999

The twisting and extrusion process of the product with involute helical fin from the round billet is developed by the upper bound analysis. The twisting of extruded product is caused by the twisted die surface connecting the die entrance section and the die exit section linearly. In the analysis, the internal shear surface is defined as the curved twisted plane from the taisting of die surface and the shear work is calculated by the consumption of shear energy The increase rate of angular velocity is determined by the minimization of plastic work. The results of the analysis show that the angular velocity of the extruded product increases with the die twisting angle, the reduction of area, and decreases with the die length, the friction condition.

• 한국초전도ㆍ저온공학회논문지
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• 제15권4호
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• pp.34-38
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• 2013

According to the increase of electric consumption nowadays, power system becomes complicated. Due to this, the size of single line-to-ground fault from power system also increases to have many problems. In order to resolve these problems effectively, an Superconducting Fault Current Limiter(SFCL) was proposed and continuous study has been done. In this paper, an SFCL was combined to the neutral line of a transformer. An superconductivity has the characteristics of zero resistance below critical temperature. because of this, SFCL has nearly zero resistance. so we connecting SFCL to neutral line will not only have any loss in the normal operation but also have the less burden of electric power because of only limiting the initial fault current. We analyzed the characteristics of current, voltage according to the changes of turn ratio of 3 phase system in case of combinations of an SFCL to the neutral line. It was confirmed that the limiting rate of initial fault current by the increase of turn ratio was reduced.

• 대한전기학회:학술대회논문집
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• 대한전기학회 1995년도 추계학술대회 논문집 학회본부
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• pp.64-66
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• 1995

This paper presents a new approach to evaluate optimal basic reliability indices of electric distribution systems using genetic algorithm. The use of optimal reliability evaluation is an important aspect of distribution system planning and operation to determine adequacy reliability level of each area. In this paper, the reliability model is based on the analytical method, connecting component failure to load point outage in each section. The proposed method applies genetic algorithm to calculate the optimal values of basic reliability indices, ie. failure rate and repair time, for a load point in the power distribution system, subject to minimizing interruption cost. Test results for the model system are reported in the paper compared with a direct optimization method(gradient projection).

• 한국통신학회논문지
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• 제15권5호
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• pp.426-433
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• 1990

본 연구는 2B+D ISDN 기본 액세스 트래픽을 집선하는 통합형 집선장치를 제안하고 분리형 집선방식과의 비교를 수행한다. 이 시스템의 특성을 비트속도 종류별로 출력 채널수, 가입자수, 인가된 트래픽 양 등의 매개변수에 의해 분석하였다. 분석 결과 여기에 제안한 집선 방식이 CCITT가 권고한 단순 다중화 방식이나 분리형 집선 방식에 비하여 T1 캐리어에 의해 시스템에 연결 가능한 ISDN 기본 액세스 가입자수를 확실히 증가시킨 결과를 보인다.

• 한국통신학회논문지
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• 제15권5호
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• pp.413-425
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• 1990

본 연구에서 2B+D ISDN 기본 액세스 트래픽을 집선하는 분리형 집선장치를 제안한다. 이 시스템의 특성을 비트속도 종류별로 출력 채널수, 가입자수, 인가된 트래픽 양 등의 매개변수에 의해 분석하였다. 분석 결과 여기에 제안하 집선방식이 T1 캐리어에 의해 시스템에 연결 가능한 최대 가입자수를 CCITT가 제안한 단순다중화 방식에 비해 확실히 증가시키는 결과를 나타낸다.

• Journal of Chest Surgery
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• 제19권4호
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• pp.543-548
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• 1986

Massive air embolism during cardiopulmonary bypass is uncommon but serious and often lethal complication. Following this catastrophic event, the immediate institution of retrograde arterial blood perfusion via superior vena cava was made to remove air emboli from cerebral circulation. This method was performed by removing the arterial perfusion line from aortic cannula and connecting it to superior vena caval cannula. Then, retrograde perfusion at a flow rate of 2Umin via superior vena cava was carried out for 3 minutes. After air returning from the aortic cannula was identified, each line was connected to the cannulae primarily. In 2 cases who had massive air emboli due to air pumping into arterial line, the postoperative complete recovery resulted from this technique, which was used in conjunction with other therapy postoperatively.

• 소성∙가공
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• 제8권2호
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• pp.143-151
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• 1999

The twisting and extrusion process of the product with trapezoidal helical fin from the round billet is developed by the upper bound analysis. The twisting of extruded product is caused by the twisted die surface connecting the die entrance section and the die exit section linearly. In the analysis, the rotational velocity in angular direction is assumed by the multiplication of radial distance and angular velocity. The angular velocity is increased linearly by axial distance from the die entrance. The increase rate of angular velocity is determined by the minimization of plastic work. The results of the analysis show that the angular velocity of the extruded product increases with the die twisting angle, the reduction of area, and decreases with the die length, the friction condition.

• 한국압력기기공학회 논문집
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• 제4권2호
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• pp.1-6
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• 2008

Very High Temperature Gas Cooled Reactor (VHTR) has been selected as a high energy heat source for nuclear hydrogen generation. The VHTR can produce hydrogen from heat and water by using a thermo-chemical process or from heat, water, and natural gas by steam reformer technology. A co-axial double-tube primary hot gas duct (HGD) is a key component connecting the reactor pressure vessel and the intermediate heat exchanger (IHX) for the VHTR. In this study, a preliminary design analysis for the primary HGD of the nuclear hydrogen system was carried out. These preliminary design activities include a determination of the size, a strength evaluation and an appropriate material selection. The determination of the size was undertaken based on various engineering concepts, such as a constant flow velocity model, a constant flow rate model, a constant hydraulic head model, and finally a heat balanced model.

• 설비공학논문집
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• 제15권3호
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• pp.166-176
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• 2003

Experiments have been conducted in order to make comparisons of a alternative refrigerant (R-410A) cycle characteristic with an existing refrigerant (R-22) cycle characteristic in terms of cooling capacity and coefficient of performance (COP). The parameters examined in the present work include air flow rate, indoor/outdoor air temperatures, and indoor relative humidity. These two refrigeration cycles share all components except compressor, accumulator, oil separator, and piping connecting them. The measurements were made using an air-enthalpy calorimeter. The experimental results show that the R-410A cycle has many advantages over indoor conditions while the R-22 cycle has better performance over outdoor conditions.