In the past, the U.S. NRC(Nuclear Regulatory Commission) strictly required testing of the EDG for NPP through Reg.Guide 1.108 Rev 1. However, these test requirements acted as a deterioration and wear factor for diesel engines, and are now applying Reg.Guide 1.9 Rev 3, which relaxed regulatory requirements and improved performance monitoring. After applying the new regulatory guidelines in this study, the EDG analyzed the performance of the combustion chamber. As a result, there were no signs of deterioration or decreased performance of the current EDG. This is due to slow start, short operation time, the use of high quality fuel oil and proper maintenance. On the other hand, if the performance is proven, it is judged that proper period extension of cylinder maintenance is possible.

In recent years, the regulation of exhaust gas of automobiles has been strengthened, and various high-tech technologies have been applied to cope with exhaust gas regulations. Especially, in case of gasoline vehicles, by injecting gasoline direct injection, a large amount of carbon deposits are adsorbed in intake / exhaust valves and combustion chambers, Which is a cause of combustion. Therefore, in this study, we developed the cleaning liquid and related special tools to remove carbon deposits in the combustion chamber, and developed the cleaning process of the combustion chamber and tried to understand the effect on the engine performance improvement. In order to prevent the release of heavy metals after burning, the cleaning effect of the cleaning liquid was investigated by temperature and the influence of the knocking of the engine on the cleaning performance.

Signal fire was a communication system which deliver urgent news by smoke and light. It informed the condition of the border to the central government and the military base rapidly. This research was to analyze the border signal-fire which is the main facility of military protective duty for safety of sea side in chosun dynasty. The results of this research were described separately as follows. 1. The border signal-fire has three types of facility layout, The majority was one-site, near two-site, separate type. The majority was near two-site type. 2. Plan configuration of signal-fire stand which is separated with circle, oval, round-rectangular and rectangular type roughly was constructed with circle type generally. Four types of signal-fire stand was observed in southern and western sea side impartially. However, in eastern side, circle type of signal-fire stand was mainly found. Therefore, regional characteristics could be considered partially. 3. The height of signal-fire stand was about 8～10m. The diameter of combustion chamber on the signal-fire stand was 2～3m in circle type, and the dimension of rectangular type was about 1.9×1.9～3.2×3.0m. 4. Building base that protect ground moisture and infilteration of rainfall was found in 10 border singal-fire, the height of it was about 0.3m～2.5m.

예연소실식 디젤기관에 있어서 박용부하운전조건에 따른 연소특성을 규명하기 위해 예언소실의 압력데이터를 single-zone, single-chamber의 열역학적 해석에 적용하여 연소해석을 행한 결과 다음과 같은 결론을 얻었다. 1) 부하가 증가함에 따라 최고압력이 상승하고 그 위치가 크랭크각도상 후진되었다. 2) 착화 지연시간은 부하에 관계없이 거의 일정하고, 부하가 증가할수록 가연 혼합기 형성에 소요되는 흡열량은 겉보기로 감소하였다. 3) 예혼합 연소단계의 열발생 양상은 부하에 관계없이 거의 비슷하고, 예혼합 연소시간은 부하가 증가할수록 짧아졌다. 4) 부하가 증가함에 따라 예혼합 연소량은 다소 증가하나 일정 연공비 이상에서는 거의 일정했다. 5) 예혼합 연소분율은 부하가 증가함에 따라 감소했다.(이 논문의 결론부분임)

열선유속계를 이용하여 디이젤 기관 연소실내의 한점에서 유속을 측정한 결과는 다음과 같은 결론을 얻었다. 1. 연소실내의 유동은 cylinder의 원주방향의 속도 성분이 크며, 유속변화는 밸브 timing과 피스톤 속도등에 밀접한 관계가 있다. 2. 유속은 흡입시부터 증가하여 압축행정중 흡입밸브가 닫히는 60˚ABDC에서 최대치를 갖고 이후 피스톤의 속도가 감소함에 따라 유속도 감소하여 팽창행정중 배기 밸브가 열리는 120˚ATDC에서 다시 증가하였다. 3. 평균유속은 shroud 밸브 사용시가 no shroud 밸브 사용시보다 낮지만 shroud 밸브 사용시 흡입행정에서 난류강도가 가장 크게 나타났다. 4. 90˚shroud 밸브 사용시가 120˚shroud 밸브 사용시보다 난류강도는 더 크고, 90˚shroud의 180˚위치에서 난류강도가 제일 크게 나타났다.(이 논문의 결론부분임)

The coal gasification fuel is important to replace petroleum fuel. Also they have many benefits for reducing the air pollution. Measurements on the combustion characteristics of synthetic gas from coal gasification have been conducted as compared with LPG in constant volume combustion chamber. The fuel is low caloric synthetic gas containing carbon monoxide 30%, hydrogen 20%, carbon dioxide 5%, and nitrogen 45%. To elucidate the combustion characteristics of the coal gasification fuel, the combustion pressures, combustion durations, and pollutants(NOx, CO2, CO) are measured with equivalence ratios(ø), and initial pressures of fuel-air mixture in constant volume chamber. In the case of the coal gasification fuel, maximum combustion pressure and NOx concentration are lower rather than LPG fuel. However CO and CO2 emission concentration are similar to that of LPG fuel.