• Journal of the Korean Institute of Telematics and Electronics
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• v.22 no.1
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• pp.53-60
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• 1985

A computer vision system for robot is developed which can recognize a variety of two dimensional complex objects in gray level noisy scenes. the system is also capable of determining the position and orientation of the objects for robotlc manipulation. The hardware of the vision system is developed and a new edge tracking technique is also proposed. The linked edges are approximated to sample line drawing by split and merge algorithm. The system extracts many features from line drawing and constructs relational structure by the concave and convex hull of objects. In matching process, the input obhects are compared with the objects database which is formed by learning ability. Thelearning process is so simple that the system is very flexible. Several examples arc shown to demonstrate the usefulness of this system.

• Korean Journal of Computational Design and Engineering
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• v.5 no.4
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• pp.380-392
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• 2000

This paper proposes a qualitative reasoning approach for the spatial configuration of mechanisms that could be applied in the early phase of the conceptual design. The spatial configuration problem addressed in this paper involves the relative direction and position between the input and output motion, and the orientation of the constituent primitive mechanisms of a mechanism. The knowledge of spatial configuration of a primitive mechanism is represented in a matrix form called spatial configuration matrix. This matrix provides a compact and convenient representation scheme for the spatial knowledge, and facilitates the manipulation of the relevant spatial knowledge. Using this spatial knowledge of the constituent primitive mechanisms, the overall configuration of a mechanism is described and identified by a spatial configuration state matrix. This matrix is obtained by using a qualitative reasoning method based on sign algebra and is used to represent the qualitative behavior of the mechanism. The matrix-based representation scheme allows handling the involved spatial knowledge simultaneously and the proposed reasoning method enables the designer to predict the spatial behavior of a mechanism without knowing specific dimension of the components of the mechanism.

• Journal of Institute of Control, Robotics and Systems
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• v.17 no.4
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• pp.353-361
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• 2011

A precise embedded ultrasonic localization system is developed for autonomous mobile robots in indoor environments, which is essential for autonomous navigation of mobile robots with various tasks. Although ultrasonic sensors are more cost-effective than other sensors such as LRF (Laser Range Finder) and vision, they suffer inaccuracy and directional ambiguity. First, we apply the matched filter to measure the distance precisely. For resolving the computational complexity of the matched filter for embedded systems, we propose a new matched filter algorithm with fast computation in three points of view. Second, we propose an accurate ultrasonic localization system which consists of three ultrasonic receivers on the mobile robot and two or more transmitters on the ceiling. Last, we add an extended Kalman filter to estimate position and orientation. Various simulations and experimental results show the effectiveness of the proposed system.

• The Journal of Korean Academy of Orthopedic Manual Physical Therapy
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• v.16 no.1
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• pp.57-63
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• 2010

The palpation of spinous process and transverse process of vertebra are important part of the assesment and treatment from Orthopedic manual therapy. But the palpation area is descriptive differently each of literatures. So we generally got these outcomes. : There are C2, C3, C4 and C6 process as a bony landmarks and these are important part of establish the precise location of pain appears from cervical spine. Even though C7 process regard a prominent part, it is hard to distinguish C6 and process of T1. Thru that differentiation, grab the patient's forehead and try them cervical and hyper-extension check any movement of process or put on the fingers on C7 preocess and check the movement. The palpation of thoracic spine process is the land mark which determines general level orientation in the spine easily, there are T2, T7 spinous process. However, It is depends on how do you test the patient's arm when you palpate it and it can effect on spinous process. The transverse process of C1 is the only spot for palpation in cervical spine, and T1-3, T12 transverse process can palpate it when it stands on the process. The end of T4-6, T11 is placed on middle on vertebra of transverse process and transverse process. T7-9, T10 transverse process is place on same position as spinous process which is upper part of the spine.

• Journal of Sensor Science and Technology
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• v.27 no.6
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• pp.414-420
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• 2018

To augment emotion and immersion in virtual reality (VR), technological research based on scent displays have increased in recent years. The results of extensive studies have enabled the development of methods to interface head mounted displays (HMDs) with scent devices, and the possibility of VR applications of this development was identified via several demonstrations in actual VR environments. Despite all these efforts, more practical methods and conditions for scent display in VR environments are yet to be developed. To efficiently interface VR and scent, this study proposes three ways to set the position for scent display and scent conditions. The first is scent display using local positioning in the VR engine, the second is scent display using the relative distance and orientation between user and object in VR environments, and the third is scent display using time setting. In this study, we developed scent devices using a piezo actuator to validate the proposed method and successfully conducted demonstrations and experiments.

• Journal of Positioning, Navigation, and Timing
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• v.11 no.4
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• pp.351-360
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• 2022

Autonomous vehicles require precise knowledge of their position, velocity and orientation in all weather and traffic conditions in any time. And, these information is effectively used for path planning, perception, and control that are key factors for safety of vehicle driving. For this purpose, a high precision GNSS technology is widely adopted in autonomous vehicles as a core localization and navigation method. However, due to the lack of infrastructure as well as cost issue regarding GNSS correction data communication, only a few high precision GNSS technology will be available for future commercial autonomous vehicles. Recently, a high precision GNSS sensor that is based on a Broadcast-RTK system to dramatically reduce network maintenance cost by utilizing the existing broadcasting network is released. In this paper, we present the performance test result of the broadcast-RTK-based commercial high precision GNSS receiver to test the feasibility of the system for autonomous driving in Korea. Massive measurement campaigns covering of Korea region were performed, and the obtained measurements were analyzed in terms of ambiguity fixing rate, integer ambiguity loss recovery, time to retry ambiguity fixing, average correction information update rate as well as accuracy in comparison to other high precision systems.

• Journal of Institute of Control, Robotics and Systems
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• v.9 no.11
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• pp.925-936
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• 2003

The manipulability analysis of the parallel-type rolling mill proposed in Hong et al. [1] is re-visited. The parallel rolling mill uses two Stewart platforms in opposite direction for the generation of 6 degree-of-freedom motions of each roll. The objective of this new parallel rolling mill is to permit an integrated control of the strip thickness, strip shape, pair crossing angle, uniform wear of rolls, and tension of the strip. New forward/inverse kinematics problems, in contrast with [1], are formulated. The forward kinematics problem is defined as the problem of finding the roll-gap and the pair-crossing angle of two work rolls for given lengths of twelve legs. On the other hand, the inverse kinematics problem is defined as the problem of finding the lengths of twelve legs when the roll-gap, the pair-crossing angle, and the position and orientation of one work roll are given. The method of manipulability analysis used in this paper follows the spirit of [1]. But, because the rolling force and moment exerted from both upper and lower rolls have been included in the manipulability analysis, more accurate results than the use of a single platform can be achieved. Two. kinematic parameters, the radius of the base and the angle between two neighboring joints, are optimally designed by maximizing the global manipulability measure in the entire workspace.

• Journal of Korean Elementary Science Education
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• v.33 no.4
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• pp.634-645
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• 2014

The purpose of this study was to analyze the teachers' stages of concern and levels of use on STEAM of the 2009 elementary science curriculum and to support effective application according to the teachers' stages and levels. Therefore this study was conducted by the Concerns-Based Adoption Model (CBAM). The total number of 113 teachers participated in this study. The results of the study were as follows: First, most teachers were in the stage of awareness. Second, the results of the chi-square test showed that the stages were significantly different according to their positions, training experiences and final degrees (p<.05). Third, about half of teachers were in the level of orientation and preparation. The others were in the level of routine, integration and renewal. Fourth, the results of the chi-square test showed that the levels were significantly different with the categories of their gender, position, age, career in education, workplace and training experience (p<.05). Fifth, the correlation coefficient between stages of concern and levels of use (r=.59) was relatively high (p<.05). Based on these results, we suggested that the support of application should be provided according to the teachers' stages and levels.

• Proceedings of the KSME Conference
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• 2003.11a
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• pp.1494-1499
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• 2003

Kinematic calibration is a process whereby the actual values of geometric parameters are estimated so as to minimize the error in absolute positioning. Measuring all components of Cartesian posture, particularly the orientation, can be difficult. With partial pose measurements, all parameters may not be identifiable. This paper proposes a new device that can be used to identify all kinematic parameters with partial pose measurements. Study is performed for a six degree-of-freedom fully parallel Hexa Slide manipulator. The device, however, is general and can be used for other parallel manipulators. The proposed device consists of a link with U joints on both sides and is equipped with a rotary sensor and a biaxial inclinometer. When attached between the base and the mobile platform, the device restricts the end-effector's motion to five degree-of-freedom and can measure position of the end-effector and one of its rotations. Numerical analyses of the identification Jacobian reveal that all parameters are identifiable. Computer simulations show that the identification is robust for the errors in the initial guess and the measurement noise.

• Proceedings of the Korean Vacuum Society Conference
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• 2011.02a
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• pp.325-325
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• 2011

Very initial stage of oxidation process of Si (001) surface at room temperature (300 K) and high temperature (1200 K) was investigated using large scale molecular dynamics simulation. Reactive force field potential [1] was used for the simulation owing to its ability to handle charge variation as well as breaking and forming of bonds associated with the oxidation reaction. The results show that oxygen molecules adsorb dissociatively or otherwise leave the silicon surface. Initial position and orientation of oxygen molecule above the surface play important role in determining final state and time needed to dissociate. At 300 K, continuous transformation of ion $Si^+$ (or suboxide Si2O) to $Si2^+$ (SiO), $Si3^+$ (Si2O3) and finally to $Si4^+$ (SiO2) clearly observed. High temperature silicon surface provide heat energy that enable oxygen atom to penetrate into deeper silicon surface. The heat energy also retards adsorption process. As a result, transformation of ion $Si^+$ is impeded at 1200 K.