• Journal of Institute of Control, Robotics and Systems
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• v.6 no.10
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• pp.936-941
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• 2000

Advanced space transportation systems, such as the National Aerospace Plane or an Orbital Transfer Vehicle, have atmospheric maneuvering capabilities. For such vehicles the use of aeroassisted orbital transfer from a high Earth orbit to a low Earth orbit, with unpowered flight in the atmosphere, has the potential for significant fuel savings compared to exoatmospheric Hohmann transfer. However, to exploit the fuel savings that can be achieved by using the Earths atmosphere to reduce the vehicles energy, a guidance law is required, and it must be able to handle large unpredictable fluctuations in atmospheric density, on the order of ${\pm}$50% relative to the 1962 US Standard Atmosphere. In this paper aeroassisted orbital transfer is considered as a differential game, with Nature controlling the atmosphere density to yield a worst case (min-max fuel required) atmosphere, from which the guaranteed playable set boundary are achieved. Inside the playable set, it is guaranteed that the vehicle achieves the optimal atmospheric exit condition for the minimum fuel consumption regardless of the atmospheric density variations.

• Journal of the Korea Society of Computer and Information
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• v.9 no.1
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• pp.63-70
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• 2004

This paper describes modeling, design and performance test results of infrared thermal image target system which can generate infrared thermal image on aircraft. The system is designed to control image shape and intensity so that the infrared image shape and its emitting intensity are so similar to that of real aircraft. When applying the technique suggested in this paper, the system consumes only small electric power energy about 30(㎾) to generate infrared thermal image which is equivalent to that of real aircraft under full power operation. After verifying performance test, the system developed here has been used as a target for korean potable surface to air missile(KPSAM) at the stage of evaluation test such as target adaptive guidance test and auto-pilot logic test.

• Journal of the Institute of Electronics Engineers of Korea CI
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• v.47 no.6
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• pp.124-130
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• 2010

Current traffic guidance system offers the information of traffic light using a speaker to everybody including the blinds without object certification. Therefore, the current system gives stress by noisy sound to normal person. It is difficult for the blind to hear informations such as location, current traffic sign light status, and weather information, because of the vehicle noise and surroundings noise. If the blind or sight disabled person who has the RFID tag or has a white stick with RFID tag approaches to street crossing, RFID reader recognizes the tag and it serves necessary information through speaker or bluetooth. And also it is possible for the blind to use less expensive one with RFID tag than the white stick with RFID Reader.

• Journal of Drive and Control
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• v.17 no.3
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• pp.9-14
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• 2020

A special purpose machine with two manipulators and quadruped crawler system is being developed to work at disaster sites where it is intended to quickly respond in the initial stages after the event. In this study, a terrain recognition module is developed so that the above special purpose machine can quickly obtain ground information to help choose its path while recognizing objects in its way, this is intended to enhance the remote driver's limited situational awareness. Terrain recognition modules were developed for two tasks (real-time path guidance, precision terrain measurements). The real-time path guidance analyzes terrain and obstacles while moving, while the precision terrain measurement feature provides more accurate terrain information by precisely measuring the ground in front of the vehicle while stationary. In this study, an air-cooled sensor protection module was developed so that the terrain recognition module can continue its vital tasks in the event of exposure to foreign substances, including scattered dust, mist and rainfall, as well as high temperatures.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.38C no.4
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• pp.359-364
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• 2013

In this paper, we propose a direct sequence ultra wideband (DS-UWB) radar system based on correlation accumulation in the fields of the ship traffic control and the safe ship operation including docking guidance systems. The proposed DS-UWB radar system averages out the noise by accumulating correlator outputs, and thus, provides a reliable distance estimation performance with a shorter estimation time compared with conventional DS-UWB radar systems. From numerical results, it is confirmed that the proposed DS-UWB radar system has not only a shorter average correlation processing time, but also a better distance estimation performance.

• The Journal of Korean Orthopaedic Ultrasound Society
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• v.5 no.1
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• pp.50-59
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• 2012

In the domain of orthopaedic surgery, application of regional nerve block for surgery or pain control in upper and lower extremities has been increased. By performing regional block of popliteal (sciatic), femoral, proximal saphenous nerve and ankle block under guidance of ultrasound, not only the safety, but also success rate of the procedure has increased, and amount of local anesthetics could be used less, too. Since the perineural single injection or continuous catheterization of diluted local anesthetics was performed more precisely and easily by the guidance of ultrasound, postoperative pain could be controlled without complications of PCA such as nausea, vomiting, etc. We will discuss about this ultrasound guided regional nerve block.

• International Journal of High-Rise Buildings
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• v.7 no.4
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• pp.299-311
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• 2018

As engineered timber such as Glulam is seeing increasing use in tall timber buildings, building codes are adapting to allow for this. In order for this material to be used confidently and safely in one of these applications, there is a need to understand the effects that fire can have on an engineered timber structural member. The post-fire resilience aspect of glulam is studied herein. Two sets of experiments are performed to consider the validity of zero strength guidance with respect to short duration fire exposure on thin glulam members. Small scale samples were heated in a cone calorimeter to different fire severities. These samples illustrated significant strength loss but high variability despite controlled quantification of char layers. Large scale samples were heated locally using a controlled fuel fire in shear and moment locations along the length of the beam respectively. Additionally, reduced cross section samples were created by mechanically carving a way an area of cross section equal to the area lost to char on the heated beams. All of the samples were then loaded to failure in four-point (laterally restrained) bending tests. The beams that have been burnt in the shear region were observed as having a reduction in strength of up to 34.5% from the control beams. These test samples displayed relatively little variability, apart from beams that displayed material defects. The suite of testing indicated that zero strength guidance may be under conservative and may require increasing from 7 mm up to as much as 23 mm.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2011.10a
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• pp.605-606
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• 2011

최근 PC 기반의 새로운 입력장치인 키넥트(Kinect) 센서에 대한 연구사 활발하게 진행되고 있다. 키넥트 센서의 가장 큰 이점은 2차원 평면 영상정보에 대하여 새롭게 추가된 깊이(Depth) 정보를 얻을 수 있다는 것이다. 이것은 이전에 등장했던 다른 인터페이스보다 새로운 차원의 인터페이스로서 2차원의 영상 정보로부터 한 차원 확장된 3차원의 정보를 활용할 수 있다는 점에서 그 의미가 크다고 볼 수 있다. 본 논문에서는 이러한 2차원 영상정보와 추가된 깊이 정보를 활용하여 사람의 영상정보와 사람의 위치 정보를 활용하여 위치한 환경의 조명을 제어할 수 있도록 시스템을 구성하였다. 또한, 키넥트의 다양한 성능을 검토하기위하여 3개의 키넥트를 사용하였으며 중첩된 영상정보를 30%의 중복도를 가지도록 구성하여 다양한 활용가능성을 검토하였다. 구현한 시스템을 통하여 사람을 추적할 수 있도록 알고리즘을 개발하고, 추적된 사람의 위치 정보를 통하여 LED 조명을 제어할 수 있는 키넥트 기반의 조명제어 시스템을 제시하고자 한다.

• The Research Journal of the Costume Culture
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• v.25 no.6
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• pp.757-772
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• 2017

Appearance management is a serious issue for adults and young people in Korean society. People of various ages have used diverse means to improve their appearances. This study focused on dieting as an appearance management behavior in female adolescents. Dieting behaviors are not just a means to improve appearance; they may also relate to individuals' beliefs and self-control. The importance of individual psychological/personality factors cannot, therefore, be ruled out. Such factors can help explain personality factors explain "what causes a compulsive diet and what factors can alleviate it". This study reviewed the literature on perfectionism and self-control as individual personality factors, and empirically examined the effects of these variables on perceived body distortion and dieting behaviors. We performed a structural equation model analysis to verify our hypothesis. The results are as follows: we found perfectionism to be positively related to perceived body distortion and dieting behaviors; we also found self-control to be negatively related to perceived body distortion though unrelated to dieting behaviors; finally, our analysis identified a relationship between perceived body distortion and dieting behaviors. These results indicate that perfectionism and self-control should be considered when conducting guidance and counseling sessions on issues related to dieting behaviors for adolescent' appearance management. This paper concludes by discussing the study's implications and limitations.

• Journal of Biosystems Engineering
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• v.21 no.3
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• pp.283-292
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• 1996

Automatic guidance of farm tractors would improve productivity by reducing operator fatigue and increasing machine performance. To control tractors within $\pm$5cm of the desired path, fuzzy and adaptive steering controllers were developed to evaluate their characteristics and performance. Two input variables were position and yaw errors, and a steering command was fed to tractor model as controller output. Trapezoidal membership functions were used in the fuzzy controller, and a minimum-variance adaptive controller was implemented into the 2-DOF discrete-time input-output model. For unit-step and composite paths, a dynamic tractor simulator was used to test the controllers developed. The results showed that both controllers could control the tractor within $\pm$5cm error from the defined path and the position error of tractor by fuzzy controller was the bigger of the two. Through simulations, the output of self-tuning adaptive controller was relatively smooth, but the fuzzy controller was very sensitive by the change of gain and the shape of membership functions. Contrarily, modeling procedure of the fuzzy controller was simple, but the adaptive controller had very complex procedure of design and showed that control performance was affected greatly by the order of its model.