• 한국전기전자재료학회:학술대회논문집
• /
• 한국전기전자재료학회 2009년도 춘계학술대회 논문집
• /
• pp.61-62
• /
• 2009

This paper describes the characteristics of lightning impulse current of ZnO block for transmission line arrester with external gap. The ageing parameters of lightning arresters ate impulse current, moisture ingress, temperature ageing and so on. Especially it is important to estimate the change of electrical characteristics by impulse current. Total energy applied to the ZnO arrester each time is $4/10{\mu}s$, 30kA and $2/20{\mu}s$, 10kA impulse current. Before and After the test, the residual voltage variation of varistors passed was below 5%. According to the test, it is thought that the ZnO arrester shows good stability with impulse current test.

• 한국정밀공학회지
• /
• 제16권4호통권97호
• /
• pp.46-56
• /
• 1999

A semi-actively controlled impact system which adjusts an impulse exerted by the external impact is studies. The main control variables are internal pressure difference inside the cylinder and the shock absorber displacement while it travels. Compared to a conventional one so called a passive system with a variable orifice inside the cylinder, a semi-actively controlled system utilizes an external orifice controlled by a highly fast responding electrical proportional valve. This device overcomes the temperature and viscosity change due to continuous operating and keeps the desired pressure difference and displacement in every operation. In this article a new prototype impact system is designed and manufactured based on a semi-actively control system. Through computer simulations and experiments, we verify the possibility of controlling the shock absorber pressure and displacement. After investigating the control performance a modified semi-actively controlled system with better control performance is also proposed.

• Advances in pediatric surgery
• /
• 제20권2호
• /
• pp.58-61
• /
• 2014

Palpable inguinal mass in children should be differentiated from inguinal hernia, hydrocele, lymph node, and tumor. Though using ultrasonography, fatty tumor would be misdiagnosed as incarcerated inguinal hernia containing fatty component. We experienced the huge inguinal lipoblastoma in 5-year-old girl mimicking recurrent incarcerated hernia. Laparoscopic exploration revealed it was not incarcerated hernia but well demarcated bulging mass from abdominal wall. Mass was about $10{\times}4{\times}3cm$ and extended from internal inguinal ring to saphenous opening. It was near total excised because of right external iliac vein injury. Pathologically, it was proven as lipoblastoma containing mature adipocyte with lipoblast and fibrous septa. Postoperatively, we noticed a segmental thrombotic occlusion of external iliac vein. After 1 year, she has no symptom related to occluded vessel. The remained lipoblastoma showed no interval change. Even lipoblastoma has a good prognosis with low recurrence rate, we need careful follow-up.

• 사상체질의학회지
• /
• 제27권4호
• /
• pp.429-435
• /
• 2015

Objectives The purpose of this study was to report the effects of treatments to traumatic subcutaneous hematoma on the shin using herbal medication and external application without venesection, which had no change in spite of previous 3 weeks medical conservative treatment so it had a risk of sepsis.Methods The patient diagnosed as Soyangin was prescribed with Yangkyuksanhwa-tang. The subcutaneous hematoma lesion was treated by external application of Daehwangchija-san(大黃梔子散). We evaluated the size of hematoma, pain and gait disturbance.Results and Conclusions Subcutaneous hematoma and relevant symptoms disappeared within 11 days of admission. Any kind of sequela did not show up and skin color was recovered after 4 month later follow-up.

• 산업공학
• /
• 제22권4호
• /
• pp.359-367
• /
• 2009

The vehicle travel time between the demand points in downtown area is greatly influenced by complex road condition and traffic situation that change real time to various external environments. Most of research in the vehicle routing problems compose vehicle routes only considering travel distance and average vehicle speed between the demand points, however did not consider dynamic external environments such as traffic situation by service time zones. A realistic vehicle routing problem which considers traffic situation of smooth, delaying, and stagnating by three service time zones such as going to work, afternoon, and going home was suggested in this study. A mathematical programming model was suggested and it gives an optimal solution when using ILOG CPLEX. A hybrid genetic algorithm was also suggested to chooses a vehicle route considering traffic situation to minimize the total travel time. By comparing the result considering the traffic situation, the suggested algorithm gives better solution than existing algorithms.

• 한국전기전자재료학회:학술대회논문집
• /
• 한국전기전자재료학회 2000년도 추계학술대회 논문집
• /
• pp.9-12
• /
• 2000

Insulators for high-voltage and large-power should be endured mechanically the weight of mold bushing itself and the force of pushed from contact with circuit breaker and conductor. But dielectric breakdown could be occurred result from the external circumstances and internal factors such as chemical reaction, partial discharge, change of temperature and the relation of temperature-time in process of casting. Therefore, to get rid of external and internal factors of dielectric breakdown. Furthermore, to prevent the internal cracks, void, cavity which resulted from the contraction originated on the interface between copper and epoxy resin, formed semi-conductive layer with partially carbon painted on copper bar. The PD properties and the insulation qualities of epoxy molded insulators were improved by roles of cushions for the direction of diameter and natural sliding effects as like separated from conductor for the direction of length.

• 한국전기전자재료학회:학술대회논문집
• /
• 한국전기전자재료학회 2007년도 하계학술대회 논문집 Vol.8
• /
• pp.458-459
• /
• 2007

This paper describes the characteristics of lightning impulse current of ZnO block for transmission line arrester with external gap. The ageing parameters of lightning arresters are impulse current, moisture ingress, temperature ageing and so on. Especially it is important to estimate the change of electrical characteristics by impulse current. Total energy applied to the ZnO arrester each time is $4/10{\mu}s$, 30kA and $2/20{\mu}s$, 10kA impulse current. Before and After the test, the residual voltage variation of varistors passed was below 5%. According to the test, it is thought that the ZnO arrester shows good stability with impulse current test.

• 패션비즈니스
• /
• 제13권4호
• /
• pp.163-177
• /
• 2009

In this study, the characteristics of headwear design by John Galliano's collections had been placed under the interpreting the immanent characteristics of presented in external things. His headwear design was found to have following characteristics; ethnic forms, historical forms, natural modeling forms, artifical forms, false hair forms and abstract forms. And his headwear design was found to have folling immanent characteristics; expaned exaggeration, introduced into existing form and reconstruction, mixed with different motives, change of texture, introducing and parody by natural and artifical form, pure abstacted construction. Furthermore, it can be identified that immanent characteristics and external things are mutually linked.

• 국제초고층학회논문집
• /
• 제8권4호
• /
• pp.283-290
• /
• 2019

Corner cut, corner chamfered or a building shape change are adopted in the design of tall buildings to achieve aerodynamic superiority as well as response reduction. Kikuchi et.al pointed out that large negative peak external pressures can appear near the inside corner of set-back low rise buildings. It is therefore necessary to pay attention to facade design around steps in building surfaces. Peak wind pressures for corner cut or corner chamfered configurations are given in the AIJ code. However, they cannot be applied where there are many variations of vertical and horizontal steps. There has been no previous systematic research on peak wind pressures around steps in building surfaces. In this study, detailed phenomenon of peak wind pressures around steps in buildings are investigated focusing on vertical and horizontal distances from the building's corner.

• 한국정밀공학회지
• /
• 제14권4호
• /
• pp.119-125
• /
• 1997

The drilling experiment of carbon fiber epoxy composite material with WC-drill has been done under the various cutting conditions in order to minimize the problems occurred in the material while being drilled. It has been confirmed by a frequency analysis of the cutting force signals that the variation of cutting force resulted from the periodic variation of the angle between the ortating drill and the stacking angle of the carbon fiber. By the drilling experiment with several drills having different point angles, the drilling char- acteristics, which show the relations between the change in the point angle and cutting force or external surface condition, were analyzed.