• 한국소음진동공학회:학술대회논문집
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• 한국소음진동공학회 2008년도 춘계학술대회논문집
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• pp.255-259
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• 2008

A soft-recoil system, which is a new technology, can dramatically reduce a recoil force. Due to the inaccurate explosion, various fault modes may happen. These fault modes can cause the serious damage of the recoil system and must be suppressed to avoid them. In the present study, the fault mode control method of the soft-recoil system is investigated. A hydraulic damper is working under normal mode and a MR damper is additionally working when the fault modes happen. In the design of the fault mode controller, the detection method of the fault mode is important as well as its suppression. The results of the simulation show that the soft-recoil system performs when the fault modes happen.

• International Journal of Aeronautical and Space Sciences
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• 제8권1호
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• pp.79-86
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• 2007

In this paper, an adaptive control algorithm using system identification is proposed for an aircraft fault tolerant control system. A discrete state-space system is reformulated to be the ARX model which has the advantage in handing variable structure systems. Discrete model reference adaptive control is used to make the output of fault system follow the output of reference model. To validate the performance of the proposed control scheme, numerical simulations are performed for the high performance aircraft with control surface damage.

• 한국지진공학회:학술대회논문집
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• 한국지진공학회 2005년도 학술발표회 논문집
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• pp.388-395
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• 2005

This paper presents cost-effectiveness evaluation of semi-active control system for cable-stayed bridge under earthquake excitation. Bi-state control method with Linear Quadratic Gaussian(LQG) optimal controller is used for generic semi-active dampers. Cost-effectiveness of the structural control system is investigated by using the life-cycle cost(LCC) concept. The evaluation results show that the efficiency of semi-active control system is increased when the damage cost due to the failure of bridge system or the bridge importance is enlarged. It was also found that the damper cost had little influence on the cost-effectiveness of semi-active control system if it was relatively small to the initial construction cost.

• 디지털산업정보학회논문지
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• 제8권2호
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• pp.11-19
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• 2012

Crane systems have been widely used for transportation in building sites, ports, nuclear wastehandling operation and so on. As a typical underactuated system, an overhead crane has such merits as high flexibility and less energy consumption. And it's getting more types of cranes, universally applicable algorithms should be developed. That is the design and development of scalable algorithms are required. Developed algorithms can be used for the controller and crane overload protection that meets the requirements of the algorithm are presented. These algorithms force the state to warn the operator and stops the operation of equipment. In this paper, crane overload conditions that can cause damage to alert the operator, and to limit the operation of equipment overload protection algorithm is presented.

• 대한산업공학회지
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• 제23권2호
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• pp.249-260
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• 1997

The manufacturing environment is rife with nonlinear processes. In this context, an intelligent production controller should be able to predict the dynamic behavior of various subsystems as they react to transient environmental conditions, the varying internal condition of the manufacturing plant, and the changing demands of the production schedule. This level of adaptive capability may be achieved through a coherent methodology for a learning coordinator to predict nonlinear and stochastic processes. The system is to serve as a real time, online supervisor for routine activities as well as exceptional conditions such as damage, failure, or other anomalies. The complexity inherent in a learning coordinator can be managed by a modular architecture incorporating case based reasoning. In the interest of concreteness, the concepts are presented through a case study involving a knowledge based robotic system.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2002년도 춘계합동학술대회 논문집
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• pp.133-136
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• 2002

In maned airport, crews may have risks as they manage passenger control system in IPMS in damage situations such as fire in a airport. So the application of unmanned autonomous system can reduce the number of boarding crews and attribute to safe airplane transportation. PBBC model can be used to obtain control strategy, and airplane and enhance operators' skill by simulating the airport. The paper suggests an intelligent system of the pbbc control using microprocessor in integrated platform management system which can take measures against passenger situation of a airplane excluding unnecessary warnings with undamaged situations. The system here detected the passenger more accurately and adopted more appriate measures according to airplane status compared with conventional systems.

• 한국산업정보학회논문지
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• 제18권3호
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• pp.9-15
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• 2013

본 논문은 온실하우스 시설내의 지하수 오염방지를 위한 유비쿼터스를 이용한 펌핑 시스템의 원격제어기 개발에 있다. 본 연구에서는 수막재배에서 펌프 살수에 대한 온도와 습도를 자동으로 제어한다. 이는 지하수의 무분별한 개발을 방지하고, 또한, 물 부족인 폐공의 경우 보완조치를 못하여 환경오염의 피해가 발생하는 것을 방지할 수 있다. 연구 결과, 최적의 농작물 관리와 펌프 제어를 통해 무분별한 지하수 사용과 고갈을 막고 전기료 절감 등의 장점을 확인하였다.

• 한국농업기계학회:학술대회논문집
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• 한국농업기계학회 2017년도 춘계공동학술대회
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• pp.157-157
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• 2017

To minimize the damage by wild birds and acquire the benefits such as protection against weeds and maintenance of water content in soil, the mulching black color vinyl after seeding should be carried out. Non-contact and non-destructive methods that can continuously determine the locations are necessary. In this study, a crop position detection method was studied that uses infrared thermal image sensor to determine the cotyledon position under vinyl mulch. The moving system for acquiring image arrays has been developed for continuously detecting crop locations under plastic mulching on the field. A sliding mechanical device was developed to move the sensor, which were arranged in the form of a linear array, perpendicular to the array using a micro-controller integrated with a stepping motor. The experiments were conducted while moving 4.00 cm/s speed of the IR sensor by the rotational speed of the stepping motor based on a digital pulse width modulation signal from the micro-controller. The acquired images were calibrated with the spatial image correlation. The collected data were processed using moving averaging on interpolation to determine the frame where the variance was the smallest in resolution units of 1.02 cm. Non-linear integral interpolation was one of method for analyzing the frequency using the normalization image and then arbitrarily increasing the limited data value of $16{\times}4pixels$ in one frame. It was a method to relatively reduce the size of overlapping pixels by arbitrarily increasing the limited data value. The splitted frames into 0.1 units instead of 1 pixel can propose more than 10 times more accurate and original method than the existing correction method. The non-integral calibration method was conducted by applying the subdivision method to the pixels to find the optimal correction resolution based on the first reversed frequency. In order to find a correct resolution, the expected location of the first crop was indicated on near pixel 4 in the inversion frequency. For the most optimized resolution, the pixel was divided by 0.4 pixel instead of one pixel to find out where the lowest frequency exists.

• 한국인터넷방송통신학회논문지
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• 제14권6호
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• pp.221-227
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• 2014

본 연구에서는 사용자의 위치정보를 제공하는 GPS와 카메라가 탑재된 원격 로봇과 스마트폰 어플 기술을 응용하여 화재 발생, 원전 사고, HF 가스 누출등 과 같은 급박한 화재 상황에서 소방관을 투입하기 이전에 정확한 화재 및 가스 누출 사고 현장의 정보와 상황을 파악하여 인명 피해를 최소화 하면서 방재 활동을 실시 할 수 있도록 하고 정확한 초기 대응으로 피해를 최소화 할 수 있는 전략을 수립 할 수 있도록 하는 소형화된 원격 로봇을 설계 제작하였다. 원격로봇은 카 보디와 콘트롤러 디바이스로 구성된다. 컨트롤 디바이스의 쥐는 강도에 따라 grab의 단계를 10단계까지 변경하는 것이 가능하였다. 초기 설계모델 로봇의 유용성에 대해 확인 하였다.

• 농업과학연구
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• 제47권1호
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• pp.43-58
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• 2020

Mulching plastic is used for the purpose of maintaining soil temperature, moisture, and weed and pest prevention in agriculture. Any remaining plastic after use may contaminate the soil and damage crop growth. To solve this problem, mulching plastic wrappers have been studied and developed, but the actual use rate is quite low due to their poor performance and frequent tearing of the plastic on the field. In this study, we developed a tractor attachable mulching plastic wrapper to minimize the tearing of the mulched plastic. The developed mulching plastic wrapper consists of hydraulic motors and pumps, valves, a microcontroller, and sensors. The collecting speed of the plastic mulch was calculated considering the tractor's travel speed and the radius of the collecting drum. A proportional controller was designed to control the rotating speed of the hydraulic motor as the plastic was wound around the collection drum and the radius increased. The performance of an indoor experiment was quite promising because the difference between the collecting speed predicted by the calculation and the actual collecting speed was 2.71 rpm. Based on a field verification test, the speed difference was max. 14.28 rpm; thus, the, proportional integral derivative (PID) controller needs to be considered to control the drum speed precisely. Another issue was found when the soil covered at the edge of the plastic was hardened or the road surface was uneven, the speed control was unstable, and the plastic was torn. In future research, vibrational plows will be equipped to break-up the harden soil for collecting the plastic smoothly.