In this study, the load fluctuation of the main engine is considered to be a disturbance for the jacket coolant temperature control system of the low-speed two-stroke main diesel engine on the ships. A nonlinear PID temperature control system with satisfactory disturbance rejection performance was designed by rapidly transmitting the load change value to the controller for following the reference set value. The feed-forwarded load fluctuation is considered the set points of the dual loop control system to be changed. Real-coded genetic algorithms were used as an optimization tool to tune the gains for the nonlinear PID controller. ITAE was used as an evaluation function for optimization. For the evaluation function, the engine jacket coolant outlet temperature was considered. As a result of simulating the proposed cascade nonlinear PID control system, it was confirmed that the disturbance caused by the load fluctuation was eliminated with satisfactory performance and that the changed set value was followed.

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 this study, a winch and load motion control system design method is introduced. Especially, the winch and load (moving cart) are connected with long wire rope which is extended to few kilometers long. Therefore, the rope length changes such that many dynamic parameter values are changed as well by winding and releasing the rope from the winch system. In this paper, the authors designed the control system by considering the real time parameter variation to occupy and keep good control performance continuously. The effectiveness of introduced method was evaluated by simulation results.

Recently, the concept of damped outrigger system has been proposed for tall buildings. But, structural characteristics and design method of this system were not sufficiently investigated to date. In this study, the dynamic response control performance of outrigger damper has been analyzed. To this end, a simplified analysis model with outrigger damper system has been developed. Use the El Centro seismic(1940, NS) analysis was performed. Analysis results, on the top floor displacement response to the earthquake response, did not have a big effect. However, acceleration response control effect was found to be excellent. The increase of outrigger damper capacity usually results in the improved control performance. However, it is necessary to select that proper stiffness and damping values of the outrigger damper system because, the outrigger damper having large capacity is result in heavy financial burden.

본 연구는 ‘피오네’ 포도 무핵재배 생력화를 위한 생장조정제 이용과 착과량 조절이 과실의 특성과 품질에 미치는 영향을 구명하고자 실시하였다. 착과량 조절에 의한 과방중은 신초당 70립/1송이로 하였을 때, 681.6 g으로 가장 무거웠으며,35립/2송이에서 가장 낮은 결과를 나타냈다. 과립중은 신초당50립/1송이에서 10.1 g으로 가장 높은 결과를 보였던 반면, 송이수 및 착립수가 많을수록 낮아졌다. 품질은 신초당 50립/1송이에서 당도는 17.3 oBrix로 다른 처리구에 비해 유의하게높았고, 안토시아닌, 명도, 적색도 등도 좋았다. 수확기는 농가관행 70립/1송이 처리구의 8월 하순 대비 50립/1송이 처리구에서는 8월 상순으로 20일 정도 단축되었다. 이로서 신초당50립/1송이의 500 g 정도의 착과량 조절이 상품성 향상에 적정하였다. 무핵 생력화를 위한 GA3 + TDZ 혼용 1회 처리에서 과방중은 TDZ 농도가 높을수록 무거운 경향을 보였으며, 대조구 568.9 g 대비 모든 처리구에서 낮은 과방중을 보였으나,GA325 mg·L−1 + TDZ 10 mg·L−1처리 구에서 상품성을 향상할수 있었다. GA3에 CPPU와 TDZ 혼용 2차 처리의 경우, 과방중은 처리 농도가 높은 GA325 mg·L−1+CPPU 20 mg·L−1처리 구에서 694.2 g으로 가장 무거웠으며, GA325 mg·L−1 + TDZ 5 mg·L−1처리구와 GA325 mg·L−1+CPPU 10 mg·L−1처리 구에서 당도가 높고, 산도는 낮아 품질 면에서 상품성이 우수하였고,과립비대에 TDZ보다 CPPU의 영향을 더 잘 받는 것으로 나타났다. 전엽 5매 출현시 GA3 5 mg·L−1처리 구에서 착립밀도 개선에 노동력 절감 효과가 있음을 알 수 있었다.

Most of steam power plant in Korea are heating the feed water system to prevent freezing water flowing in the pipe in winter time. The heating system is operated whenever the ambient temperature around the power plant area below 5 degree Centigrade. But this kind of heat supplying system cause a lot of energy consuming. If we think about the method that the temperature of the each pipe is controled by attaching the temperature measuring sensor like RTD sensor and heat is supplied only when the outer surface temperature of the pipe is under 5 degree Centigrade, then we can save a plenty of energy. In this study, the computer program package for simulation is used to compare the energy consumption load of both systems. Energy saving rate is calculated for the location of Youngweol area using the data of weather station in winter season, especially the January' severe weather data is analyzed for comparison. Various convection heat transfer coefficients for the ambient air and the flowing water inside the pipe was used for the accurate calculation. And also the various initial flowing water temperature was used for the system. Steady state analysis is done previously to approximate the result before the simulation. The result shows that the temperature control system using RTD sensor represents the high energy saving effect which is more than 90% of energy saving rate. Even in the severe January weather condition, the energy saving rate is almost 60%.

최근들어 풍진동 제어를 위한 TMD의 설치가 증가하고 있는 상황이지만, 아직 국내에서 건물의 완공 후 TMD의 설치로 인한 풍진동 제어성능 평가는 제대로 이루어지지 않고 있다. 이는 가속도계 등을 이용한 현장계측을 통해 태풍 등으로 인한 건물과 TMD의 거동을 알 수는 있으나, 풍하중을 직접 계측하는 것이 현실적으로 불가능하기 때문이다. 즉, 풍하중을 계측하지 못하기 때문에 동일한 풍하중 상황에서 TMD가 작동을 할 때와 작동을 하지 않을 때의 비교분석이 불가능하고 나아가 TMD의 풍진동 제어성능 분석이 매우 어려운 상황이다. 본 논문에서는 계측된 건물과 TMD의 가속도 응답으로부터 풍하중을 역추정하여 TMD의 풍진동 제어성능을 분석하는 방법을 제안하고자 한다. 이를 위해 TMD와 구조물 응답으로부터 하중을 역추정하는 방법으로 연속시간 영역에서 칼만 필터링을 이용하는 기법을 제시하고자 한다. 최종적으로 역추정으로 구한 하중을 이용하여 수치해석을 통해 TMD가 설치되지 않은 구조물의 응답을 구하여 TMD의 설치로 인한 풍진동 제어성능을 분석하고자 한다.

This study analyzes structural stress and fatigue on control arm of automobile under nonuniform load. Maximum equivalent stress at bolt part is shown with 419.1MPa and the corner is deformed with maximum displacement of 1.1628mm. Among 3 cases of nonuniform fatigue loads applying on control arm, ‘AE bracket history’with the severest change of load becomes most unstable but ‘ample history’becomes most stable. In case of ‘ample history’with the average stress of -105 MPa to 105 MPa and the amplitude stress of 0 MPa to 105MPa, the possibility of maximum damage becomes 3%. This stress state can be shown with 6 times more than the damage possibility of ‘AE bracket history’or ‘AE transmission’ Safety and durability on automobile can be effectively improved by applying the fatigue analysis result on control arm.

Sliding mode control(SMC) keeps responses of a structure in sliding surface when the structure is stable. Recently, this method has been investigated for application to seismically excited civil engineering structures because it can design both linear controller and non-linear controller such as bang-bang controller. This paper presents vibration control of the SDOF system using saturated sliding mode controller, of which maximum conrtol force is limited. It is assumed that the response of a structure is stationary random process and control dampers do not affect the modal shapes, and the structure has proportional damping. SMC method can be used to get the equivalent damping ratios of a SDOF system with non-linear control dampers such as friction dampers as well as linear control dampers. The determinated equivalent damping ratios and numerical simulation results indicate that the performance of saturated SMC method is verified.

In the offshore crane system, the requirements on the operating safety are extremely high due to many external factors. Rope extension is one of the factors producing vertical vibration of load. In this study, the load is carried by the motor-winch actuator control and the rope is modeled as a mass-damper-spring system. To control the load position and suppress the vertical vibration of the load, a control system based on input-output linearization method is proposed. By the simulation and experiment results with pilot crane model, the effectiveness of proposed control method is evaluated and verified.

In this study, it was modelled high-rise building applying outrigger damper system and analyzed by applying eccentric load. By controlling the variation of damping and stiffness of the damper, the seismic response control performance of outrigger damper system was analysed. An outrigger damper system is effective in controlling the top floor displacement response and torsional angle. Therefore, the damper should be selected the proper stiffness value because the variation of stiffness have an influence on the torsional angle.