• The Transactions of The Korean Institute of Electrical Engineers
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• v.63 no.1
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• pp.108-114
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• 2014

This paper proposes a generation method of a navigation guidance direction and a fuzzy controller to achieve the autonomous navigation of a mobile robot using a particle swarm optimization(PSO) scheme in unknown environments. The proposed navigation guidance direction is the direction that leads a mobile robot to arrive a target point simultaneously with avoiding obstacles efficiently according to the surrounding local informations. It is generated by selecting the most suitable direction of the many directions in the surrounding environment using a particle swarm optimization scheme. Also, a robot can reach a target point with avoiding the various obstacles by controlling the robot so that it can move from its current orientation to the navigation guidance direction using the proposed fuzzy controller. Simulation results are presented to show the feasibility and validity of the proposed robot navigation scheme.

• Journal of the Korean Society of Hazard Mitigation
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• v.6 no.1 s.20
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• pp.29-38
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• 2006

There are increasing needs to provide sufficient information on road directions through road signs for expanding cities and traffic networks. Improving efficiency of direction guidance information from road signs not only requires criteria for but also systematic approach to selecting place names that appear on road signs. As such, this paper looks at road direction information from existing road signs that leads to Suwon and investigates whether the current system of road signs provides efficient, systematic and continuous direction information for road users to easily reach their destination. In this paper, Suwon's city hall is set up as the final destination, which is linked from five other cities, Anyang, Osan, Ansan, Yongin and Seongnam. The paper attempts to find out whether there is continuity and suitable number of road signs for direction information by analyzing the road signs between these 5 cities and Suwon with respect to direction, direction advance notice and direction guidance. It is found that drivers cannot easily find the needed information on their destination from the existing road signs and that continuity of selected place names that systematically appear on road signs is insufficiency. In addition, direction guidance on road signs is problematic, because the appearance frequency of road signs is not adequate and the continuity of road signs is not effective. Moreover, there is insufficient information on local direction guidance for immediate destinations on road signs with respect to turning left or right or going straight.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.26 no.2D
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• pp.275-283
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• 2006

Recently, there are increasing needs to provide sufficient information on road signs for expanding cities and traffic networks. Improving efficiency of direction guidance information from road signs not only requires criteria for but also systematic approach to selecting place names that appear on road sings. As such, this paper looks at road direction information from existing road signs that leads to Suwon and investigates whether the current system of road sings provides efficient, systematic and continuous direction information for road users to easily reach their destination. In this paper, Suwon's city hall is set up as the final destination, which is linked from five other cities, Euiwang, Ansan, Hwaseong, Osan and Yongin. The paper attempts to find out whether there is continuity and suitable number of road signs for direction information by analyzing the road signs between these 5 cities and Suwon with respect to direction, direction advance notice and direction guidance. It is found that road users cannot easily find the needed information on their destination from the existing road signs and that continuity of selected place names that systematically appear on road signs is insufficiency. That is to say, the findings of the paper are that while it is easy for road users to find place names that are classified under land marks or the first-class selection of place names on road signs, it is difficult to obtain information from road signs on place names that are grouped under the second or third class. In addition, direction guidance on road signs is problematic, because the appearance frequency of road signs is not adequate and the continuity of road signs is not effective. Moreover, there is insufficient information on local direction guidance for immediate destinations on road signs with respect to turning left or right or going straight. Hence road signs in urban area need systematic improvement to find easily some destination.

• Proceedings of the Korean Society of Machine Tool Engineers Conference
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• 2002.04a
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• pp.500-504
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• 2002

The purpose of this paper is to implement a guidance system for an object on the road. A watch camera equipped on the auto door recognizes the direction for the destination of an object, after that it determines whether opening or closing the door, and then the door is opened automatically, based on the decision. The motion of the moving object is approximated by using the technique of the image processing of tracking images and the affine model. The direction of the moving object is predicted from image information obtained by applying linear Kalman filter to the motion estimation in order to reduce the search region, the moving position, and the direction of the center of the object. Along with the guidance function, the system has the announcing function to the object. The experimental results confirm the veridity and applicability of the proposed system.

• The Korean Journal of Pain
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• v.20 no.1
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• pp.40-45
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• 2007

Background: Caudal block is useful when anesthesia for surgery or treatment for chronic pain is needed, but this procedure has a failure rate of up to 25% even when it performed byan experienced physician. This high failure rate is usually due to improper needle placement. Methods: After gaining approval of the ethics committee, 46 patients received caudal blocks under ultrasound guidance; these were performed after the anatomical structures in the sacral hiatus had been measured with ultrasound. All these procedures were performed by the same anesthesiologist. The position and direction of the needle were identified using fluoroscopy by injecting a radio-opaque contrast through the needle. The time taken from thelidocaine injection to verification of the needle was measured and the planned nerve block was then carried out. Results: All cases of needle insertion into the sacral canal under ultrasound guidance were successful. The average duration of the procedure and the trial count were $134.1{\pm}10.1seconds$ and $1.2{\pm}0.1$, respectively. In 12 of the 46 cases (26%), the needle deviated either left or right in the sacral canal, so the direction of the needle had to be adjusted. The distance between two cornua, the depth of the sacral hiatus and the thickness and length of the sacrococcygeal ligament were $17.1{\pm}0.4$, $3.9{\pm}0.3$, $2.3{\pm}0.1$ and $24.9{\pm}0.9mm$, respectively. Conclusions: Ultrasound guidance can increase the success rate of inserting a needle into the sacral canal. However, even when ultrasound is used, the needle can deviate either left or right in the sacral canal.

• The Journal of The Korea Institute of Intelligent Transport Systems
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• v.14 no.6
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• pp.69-76
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• 2015

Although traffic information has been actively analyzed using big data, it has not been used as much with the consideration of driver characteristics. Among the various types of information, road signs can directly affect the driver. Road signs must provide the optimal information that enables drivers to reach their destinations with ease as well as information suitable for navigation systems. However, present road sign rules provide standardized information, regardless of the road type or size. This study suggests a method for providing road information that will help drivers determine their behavior. First, the minimum character size that can be used on a road sign for each design speed was obtained with respect to the visibility and decipherability of a road sign. Instead of conventional diagram-based direction guidance, a scenario using split-based direction guidance was created. To verify the effectiveness of the provided information, a three-dimensional simulated road environment was constructed, and a driving simulator was used for the test. At a simple plane intersection, the driver was not greatly influenced by directional guidance, but at a complex, three-dimensional intersection, the driver preferred summary-based directional guidance, which is instinctive guidance, over diagram-based guidance. On the basis of the test results, a secondary verification test that applied split-based guidance at a three-dimensional intersection confirmed that the driver had no problems in making decisions.

• The Journal of Korea Robotics Society
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• v.9 no.3
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• pp.147-153
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• 2014

In this paper, we proposed a new algorithm of the guidance line extraction for autonomous weeding robot based on infrared vision sensor in wet paddy. It is the critical process for guidance line extraction which finds the central point or area of rice row. In order to improve accuracy of the guidance line, we are trying to use the morphological characteristics of rice that the direction of rice leaves have convergence to central area of rice row. Using Hough transform, we were represented the curved leaves as a combination of segmented straight lines on binary image that has been skeletonized and segmented object. A slope of the guidance line was gotten as calculate the average slope of all segmented lines. An initial point of the guidance line was determined that is the maximum pixel value of the accumulated white columns of a binary image which is rotated the slope of guidance line in the opposite direction. We also have verified an accuracy of the proposed algorithm by experiments in the real wet paddy.

• Fire Science and Engineering
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• v.25 no.2
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• pp.101-106
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• 2011

In case of an emergency such as a fire on a building and there is a need to evacuate the occupant in that building, it is important to have the guidance information effectively delivered to the evacuating occupants to guide them toward a safe direction using audio sensual media. And, it is also very important to prevent the evacuating occupants getting lost or falling astray, away from the direction toward safety. The purpose of this study, in this respect, is to examine the possible application of the precedent sound effect, with which the evacuating occupants may get a sense of the direction where the announcement comes from. With such an effect, an experiment was conducted to measure the extent to which people can hear the preceding and the following sound in terms of the acoustic pressure level changes and delay time changes, with a view to make the optimal evacuation-guidance announcement or sound. The optimal evacuation guidance sound (announcement) per each of the experimental indoors environments were as follows; 1) Regarding the optimal condition for the evacuation guidance announcement sound in the space of a lecture room, the direction of the advanced sound is positively recognized when the follow-up sound has the delaying time of 10 ms~50 ms in comparison with the advanced sound or when there is no difference between the acoustic pressures of the advanced and follow-up sounds or the acoustic pressure of the advanced sound is higher than that of the follow-up sound. 2) Regarding the optimal evacuation guidance announcement sound in the space of a hall, the advanced sound is positively recognized when the follow-up sound has the delaying time of 20 ms~60 ms in comparison with the advanced sound. 3) Regarding the optimal evacuation guidance announcement sound in the space of a gymnasium, the advanced sound is positively recognized when the follow-up sound has the delaying time of 10 ms~40 ms in comparison with the advanced sound or when the sound pressure of the advanced sound has a higher level than or the same level as that of the follow-up sound.

• Advances in aircraft and spacecraft science
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• v.9 no.5
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• pp.433-447
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• 2022

This work deals with an explicit guidance and control architecture for autonomous lunar ascent and orbit injection, i.e., the locally-flat near-optimal guidance, accompanied by nonlinear reduced-attitude control. This is a new explicit guidance scheme, based on the local projection of the position and velocity variables, in conjunction with the real-time solution of the associated minimum-time problem. A recently-introduced quaternion-based reduced-attitude control algorithm, which enjoys quasi-global stability properties, is employed to drive the longitudinal axis of the ascent vehicle toward the desired direction. Actuation, based on thrust vectoring, is modeled as well. Extensive Monte Carlo simulations prove the effectiveness of the guidance, control, and actuation architecture proposed in this study for precise lunar orbit insertion, in the presence of nonnominal flight conditions.

• Journal of the Korean Society of Safety
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• v.28 no.3
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• pp.118-122
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• 2013

For safe evacuation in the fire disaster, the evacuees must find the exit and evacuate quickly. Especially, if the evacuees don't know the location of the exit, they have to depend on the evacuation guidance system. Because the more smoke spread, the less visibility is decreasing, it is difficult to find the way to the exit by the naked eye. For theses reasons, the evacuation guidance system is highly important. However, the evacuation guidance system without change of direction has the risk that introduce to the dangerous area. In the evacuation safety assessment scenario by the evacuation simulation has the same problem. Because the evacuee in the simulation evacuate by the shortest route to the exit, the simulation result is same like the evacuation without the evacuation guidance system. In this study, it was used with MAS (Multi Agent System)-based simulation program including the evacuation guidance system to implement the change of evacuation by fire. Using this method, confidence of evacuation safety assessment can be increase.