선박 발전기의 여자기는 출력 단자 전압을 일정하게 유지하기 위하여 여자전류 제어를 통해 자속을 조정한다. 여자기 내부에 있는 전압제어기는 통상적으로 비례 적분 제어방식이 사용되는데 게인과 시정수에 의해 결정되는 응답 특성은 적절치 못한 설정값에 의 해 원하지 않는 출력을 내며 이로 인해 선내 전력의 품질과 안정성을 떨어뜨릴 수 있다. 본 논문에서는 IEEE에서 제공하는 AC4A 타입의 여자기 모델을 통해 얻을 수 있는 안정적인 입출력 데이터를 활용하여 신경망 회로를 학습시킨 후 기존의 비례 적분 제어방식의 전압제 어기를 학습된 신경망 회로 제어기로 대체하여 시뮬레이션을 수행하였다. 그 결과 기존 대비 최대 9.63%까지 오버슈팅이 개선되었으며, 안정적인 응답 특성에 대한 우수성을 확인하였다.

최근 미디어아트와 공연예술 분야에서 예술과 기술의 융합을 활용한 다원예술의 공연들이 늘어나고 있다. 공연 자와 관객들 사이의 실시간 커뮤니케이션이 이루어지는 공연예술은 관람객들이 전시의 형태로 이를 감상하는 미 디어아트와는 달리, 작가의 의도를 공연자의 퍼포먼스와 배경, 무대장치들을 통해 간접적으로 전달하는 형태를 취한다. 본 연구는 비언어적 커뮤니케이션의 형태로 관객들의 실시간 소통이 중요한 예술공연에서, 게임엔진과 실시간 인터렉션 기술들을 접목한 공연사례들을 분석해보자 한다. 게임과 영상 분야에서 주로 사용되었던 언리 얼 엔진과 비주얼 인터렉션 기술들은 실시간 리얼타임 비주얼 출력이라는 강력한 이점으로 인해 다양한 분야에 서 폭넓게 활용되고 있고, 예술공연 분야로도 점차 확대되고 있다. 따라서 미디어아트 공연분야에서 실시간 인터 렉션 기술이 접목된 다원예술 공연들을 살펴보고 어떠한 시도와 움직임들이 있는지 살펴보고 분석해보고자 한 다. 이를 통해 미디어아트 분야 뿐만 아니라, 공연예술 및 다원예술 분야에서도 미디어아트와 실시간 인터렉션 공연을 접목시킨 다양한 형태의 예술공연들이 늘어나고 관련 제작 및 방법론 연구에 도움이 되고자 한다.

판형 열교환기는 1920년대부터 본격적으로 상업화되었으며, 이후 판형 열교환기의 기본 컨셉은 지금까지도 거의 변화가 없었지만 고온, 고압 그리고 대용량 열교환에 적용되기 위해 설계 및 제작 방법들이 혁신적으로 발전하여 지금에 이르게 되었다. 판형 열교환기의 개발 트렌드는 전열 효율이 좋으면서 압 력강하가 낮고 또한 유체 분배가 잘되는 전열판의 개발과 일치한다. 본 연구에서는 이러한 트렌드를 만족 시키는 선박용 중속엔진 오일 냉각용 판형 쿨러 개발과 관련된 주요 과정들을 소개하고, 또한 개발된 판형 오일쿨러의 전열성능을 실험적으로 분석하여 이에 대한 결과를 제공하고자 한다. 본 연구에서 판형 쿨러는 구조적 특징으로 인해 직접 판벽 온도를 측정할 수 없어 수정된 Wilson Plot 방법을 응용하여 열전달계수를 구하였다. 오일-물 실험 전에 물-물 실험을 통해 우선 물측의 열전달계수와 압력강하량을 구하였고, 그 결과를 바탕으로 오일측의 열전달계수를 구하였다. 양측 모두 유량 증가에 따라 열전달 성능은 증가하였지 만, 압력강하량도 동시에 증가하였다. 그리고 실험을 통해 본 연구에서 개발된 판형 오일쿨러가 개발목표치를 성공적으로 달성하였음을 확인할 수 있었다.

In this study, to investigate the effect of physical and chemical properties of butanol on the engine performance and combustion characteristics, the coefficient of variations of IMEP (indicated mean effective pressure) and fuel conversion efficiency were obtained by measuring the combustion pressure and the fuel consumption quantity according to the engine load and the mixing ratio of diesel oil and butanol. In addition, the combustion pressure was analyzed to obtain the pressure increasing rate and heat release rate, and then the combustion temperature was calculated using a single zone combustion model. The experimental and analysis results of butanol blending oil were compared with the those of diesel oil under the similar operation conditions to determine the performance of the engine and combustion characteristics. As a result, the combustion stabilities of D.O. and butanol blending oil were good in this experimental range, and the indicated fuel conversion efficiency of butanol blending oil was slightly higher at low load but that of D.O. was higher above medium load. The premixed combustion period of D.O. was almost constant regardless of the load. As the load was lower and the butanol blending ratio was higher, the premixed combustion period of butanol blending oil was longer and the premixed combustion period was almost constant at high load regardless of butanol blending ratio. The average heat release rate was higher with increasing loads; especially as butanol blending ratio was increased at high load, the average heat release rate of butanol blending oil was higher than that of D.O. In addition, the calculated maximum. combustion temperature of butanol blending oil was higher than that of D.O. at all loads.

In this study, the change of cooling water temperature (72, 85, 95 ℃) and engine speed (1,800, 2,000, 2,200, 2,400rpm) were experimentally investigated to confirm the operation performance characteristics of auxiliary engine for refrigeration unit. The experimental setup consisted of fuel consumption meter, power meter, and heat transfer unit. The operation performances such as BSFC, exhaust temperature, power generation, and engine efficiency of the auxiliary engine showed similar characteristics in the present experimental range, according to the change of cooling water temperatures and rpms. As the torque increased, the BSFC decreased significantly and the exhaust temperature increased. The power generation increased linearly and the efficiency was insignificant at more than 40 Nm torque.

The fuel used in this study, DMM is an oxygen additive containing 42.5% oxygen by weight and dissolved in diesel fuel, also known as methyl alcohol or Dimethoxymethane (CH3-O-CH2-O-CH3). DMM, which is a colorless liquid, shows chemical characteristics of gas-liquid and is also used as a diesel fuel component. In this study, five mixtures were added to the common diesel fuel at DMM addition rates of 2.5, 5, 7.5, 10 and 12.5% by volume. A single cylinder, four strokes, DI diesel engine was used as the test engine. Experimental data were also collected at 24 engine speed-load conditions operating in steady state. The purpose of this experiment was to study the effect of the addition ratio of oxidized fuel mixed in diesel fuel on engine power and exhaust performance. When compared with the common diesel fuel, the exhaust of Smoke was substantially reduced in all DMM mixing ratios. These results indicate that DMM can be an effective blend of diesel fuel and is an environmentally friendly alternative fuel. This study also shows that smoke and NOx emissions can be reduced at the same time through the application of oxygen fuel and EGR.

The wavy fins have been widely used in the heat exchangers in coolering system, aerospace system and automotive. Especially, an automobile has the wavy fin and flat tube heat exchanger for oil cooling system. The objective of this research is the performance comparison of wavy fins for battle vehicle diesel engine oil-cooler by numerical analysis. The real type fin is the wavy fin with corrugated structure, and the comparative fin surfaces are plain, louver, lateral perforation and parallel wavy fin. The non-dimensional values of f-factor, j-factor, area goodness factor and volume goodness factor was performed on the performance comparison. The plain and louver fin shows the highest performance in pressure drop and heat transfer respectively. In the area goodness factor and volume goodness factor results, the parallel wavy fin and louver fin show the highest values at each result.

The purpose of this study is to verify the effects of a port throttling and 1/4 diagonal port masking of an intake port of an SI engine. The fuel consumption rate increased with port throttling and masking under all operating conditions. However, the rapid combustion effect was increased in all operating conditions. It is consider that this is more influential on the suction resistance than the combustion efficiency increase through intake control. In addition, the increase in the burning velocity indicates that the flame propagation speed is increased by increasing the swirl moment during combustion.

In recent years, much interest has been devoted to bio-fuels because of their beneficial effects on environment, agriculture and economic development. Raw vegetable oil – a kind of bio-fuels, still exits many downsides, is potential renewable fuel replaced for ever-exhausted fossil fuel. In this report, vegetable oil which is available in the South of Vietnam such as raw coconut oil is studied by heating up different temperature with the aim at decreasing its high viscosity and density and meeting the fuel requirements. The experiments are conducted on heated coconut oil (HCO) and fossil diesel oil (DO) using an 80hp of small marine diesel engine. The results of engine performance as using DO and HCO included engine power (Ne), specific fuel consumption (SFC), thermal efficiency (TE), emission characteristics such as carbon monoxide (CO), unburned hydrocarbon (HC), smoke, nitrogen oxides (NOx) at internal feature are measured. The experiment results show higher SFC, CO, HC and smoke emissions, and lower TE, and NOx emissions for HCO with respect to DO. In addition, this study also reveals that, 1000C of HCO is said to be the most suitable heating temperature as getting the engine performance equals to DO.

The effect of gasoline-ethanol blends on performance and NOx emission was investigated in a SI engine with port and direct fuel injection systems. The 1-D cycle simulation program of GT-Power was utilized to analyze the performance of thermodynamic cycle. The results showed that the brake torques are increased with the addition of ethanol to gasoline because of the improvements of volumetric efficiency. The engine with direct ethanol blends injection system has more power than that with port gaoline injection system, which is caused by the higher latent heat of ethanol.

The performance of organic Rankine cycle was numerically investigated to recover heat from the exhaust of a heavy-duty diesel engine. Exhaust flow rates and temperatures are obtained from the simulation of diesel cycle by using GT-Power. The net power outputs of organic Rankine cycle for 9 working fluids were calculated by cycle simulations. The results showed that as for the net power outputs and the pressure of working fluids, R21 and R245fa are suitable as working fluids for ORC in diesel engine.

This paper analyzes the simulation operation flow of Bullet physics engine. Based on this analysis, four kinds of multi-rigid-body game characters are designed. This paper also profiles the performance metrics such as the CPU utilization, the memory usage, and the computation time by multi-rigid-body character simulations. For the CPU utilization, the Tongs Vehicle is the best and provides 45.1% less than the other character simulations. The computation times of the Four-leg robot and the Dragon are longer than those of the others. The memory usage of the Dragon simulation is the largest, which is average 1.32 times more than the others. Because all parts of Dragon are composed of triangular mesh models in 3DMax. The performance profiling with the criteria such as reducing the computation time and the computing resources, the complexities of the collision shapes, and the number of rigid bodies takes an important role in the design of the multi-rigid-body game characters.

This study describes the effects of canola oil biodiesel (BD) blended fuel on the combustion performance and emission characteristics in a 4-cylinder common-rail direct injection diesel engine. In this study, with the increasing of engine loads, the biodiesel blend fuels(100 vol.% ULSD and 0 vol.% biodiesel blend, BD0; 80 vol.% ULSD and 20 vol.% biodiesel blend, BD20; 0 vol.% ULSD and 100 vol.% biodiesel blend, BD100; ULSD: ultra low sulfur diesel) were used at an engine speed of 1,500rpm. The experimental results showed that with the increasing of biodiesel blend rate, the combustion pressure decreased slightly at engine load of 20~60Nm. However, the rate of heat release (ROHR) increased clearly and ignition delay time was shortened. With the increasing of biodiesel blend rate, the carbon monoxide (CO) and particulate matter (PM) emissions were more decreased at all of the engine loads.

This study was performed to investigate the effect of fuel combustion enhancing apparatus(FCEA) for ionization of intaking air into cylinder combustion chamber on the combustion performance and emissions characteristics in a 4-cylinder common-rail direct injection diesel engine. The experiments were applied to the engine at an engine speed of 1,500rpm under 20Nm, 40Nm, 60Nm and 80Nm conditions. The test results were compared to each other with or without the FCEA. In the case of the FCEA, the combustion pressure, peak combustion pressure and rate of heat release were increased slightly and the brake specific fuel consumption(BSFC) was decreased slightly when compared to that without the FCEA under all loads at an engine speed of 1,500rpm. However, in the case of the FCEA, the nitrogen oxide(NOx) were increased slightly, the carbon monoxide(CO) and particulate matter(PM) were decreased slightly when compared to that without the FCEA under all loads at an engine speed of 1,500rpm.