• The Journal of Korea Robotics Society
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• v.8 no.3
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• pp.150-155
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• 2013

Vibrotactile actuators for small consumer electronic products, such as mobile devices, have been widely used for conveying haptic sensation to users. One of the most important things in vibrotactile actuators is to be developed in the form of thin actuator which can be easily embedded into mobile devices and to provide vibrotactile signals with wide frequency band to users. Thus, this paper proposes a thin film type haptic actuator with an aim to convey vibrotactile information with high frequency bandwidth to users in mobile devices. To this end, a vibrotactile actuator which creates haptic sensation is designed and constructed based on cellulose acetate material. A cellulose acetate material charged with an electric potential can generate vibration under the AC voltage input. It is found that the motion of the actuator can have concave or convex shape by controlling a polarity of both charged membranes and the actuator performance can be modulated by increasing level of biased electric potential. The experiment clearly shows that the proposed actuator creates enough output force to stimulate human skin with a large frequency bandwidth and to simulate various vibrotactile sensations to users.

• Journal of Institute of Control, Robotics and Systems
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• v.13 no.4
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• pp.371-376
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• 2007

This paper presents an emotion recognition and its expression system of an intelligent robot like a home robot or a service robot. Emotion recognition method in the robot is used by a facial image. We use a motion and a position of many facial features. apply a tracking algorithm to recognize a moving user in the mobile robot and eliminate a skin color of a hand and a background without a facial region by using the facial region detecting algorithm in objecting user image. After normalizer operations are the image enlarge or reduction by distance of the detecting facial region and the image revolution transformation by an angel of a face, the mobile robot can object the facial image of a fixing size. And materialize a multi feature selection algorithm to enable robot to recognize an emotion of user. In this paper, used a multi layer perceptron of Artificial Neural Network(ANN) as a pattern recognition art, and a Back Propagation(BP) algorithm as a learning algorithm. Emotion of user that robot recognized is expressed as a graphic LCD. At this time, change two coordinates as the number of times of emotion expressed in ANN, and change a parameter of facial elements(eyes, eyebrows, mouth) as the change of two coordinates. By materializing the system, expressed the complex emotion of human as the avatar of LCD.

• Journal of Korea Society of Industrial Information Systems
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• v.17 no.3
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• pp.51-57
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• 2012

Pacman is known as the terminator of the loved classic game in the world. In this paper, classic pacman game without using a keyboard or a mouse we should be able to play the game with simple hand gestures. In other words, It use motion game to be a substitute for the hand direction key using the center coordinates. Also, movements of the monster is to be replaced depending on your hand movements by extracting a pointer of hand taking pictures in the MFC dialog using Cam. In this paper, YCbCbr image is convert to RGB images to extract skin color, and multiplication operations and hybrid median filtering was used in order to obtain better images. And it is used to obtain movement of the hand area based on obtain the center of gravity of the hand region.

• Archives of Reconstructive Microsurgery
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• v.12 no.2
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• pp.112-118
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• 2003

Purpose : Soft tissue defect and exposed tendons and bones with concomitant infection in the foot and lower leg have to be covered with vascularized flap as the one stage treatment. Authors have performed 6 cases of pedicled dorsalis pedis island flaps under the loupes magnification and evaluated the benefits. Materials and methods : From 1994 through 2003, we have performed 6 pedicled dorsalis pedis island flaps for reconstruction of soft tissue defects in the foot and lower leg. The causes were trauma in 3 cases, skin necrosis and secondary infection after Achilles tendon repair in 2 cases and acute osteomyelitis in 1 case. Average age was 38 years and 5 cases were male and 1 female. The results of the procedure was evaluated by survival of the island flap, comfort in putting on shoes and walking, comfort in the donor site, comfort in the recipient site and range of motion of the ankle joint. Results : All pedicled dorsalis pedis island flaps survived except 1. Three cases felt discomfort in the dorsum of foot as the donor site and 1 case of the Achilles tendon ruptured and repaired showed limited dorsiflexion of ankle joint. Conclusion : Nonmicrosurgical pedicled dorsalis pedis island flaps under the loupes magnification are one of the useful treatment methods because procedure is rapid, survival is confident and overall reconstructive results are good.

• Transactions on Electrical and Electronic Materials
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• v.16 no.1
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• pp.16-19
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• 2015

A wearable sensing ECG T-shirt for ubiquitous vital signs sensing is proposed. The sensor system consists of a signal processing board and capacitive sensing electrodes which together enable measurement of an electrocardiogram (ECG) on the human chest with minimal discomfort. The capacitive sensing method was employed to prevent direct ECG measurement on the skin and also to provide maximum convenience to the user. Also, low power integrated circuits (ICs) and passive electrodes were employed in this research to reduce the power consumption of the entire system. Small flexible electrodes were placed into cotton pockets and affixed to the interior of a worn tight NIKE Pro combat T-shirt. Appropriate signal conditioning and processing were implemented to remove motion artifacts. The entire system was portable and consumed low power compared to conventional ECG devices. The ECG signal obtained from a 24 yr. old male was comparable to that of an ECG simulator.

• Proceedings of the Korean Information Science Society Conference
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• 1998.10c
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• pp.384-386
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• 1998

The use of hand gesture provides an attractive alternative to cumbersome interface devices for human-computer interaction(HCI). Many methods hand gesture recognition using visual analysis have been proposed such as syntactical analysis, neural network(NN), Hidden Markov Model(HMM) and so on. In our research, a HMMs is proposed for alphabetical hand gesture recognition. In the preprocessing stage, the proposed approach consists of three different procedures for hand localization, hand tracking and gesture spotting. The hand location procedure detects the candidated regions on the basis of skin-color and motion in an image by using a color histogram matching and time-varying edge difference techniques. The hand tracking algorithm finds the centroid of a moving hand region, connect those centroids, and thus, produces a trajectory. The spotting a feature database, the proposed approach use the mesh feature code for codebook of HMM. In our experiments, 1300 alphabetical and 1300 untrained gestures are used for training and testing, respectively. Those experimental results demonstrate that the proposed approach yields a higher and satisfying recognition rate for the images with different sizes, shapes and skew angles.

• Korean Journal of Computational Design and Engineering
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• v.12 no.6
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• pp.429-440
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• 2007

The purpose of this research is to develop the Human-centered CAD system in which human factors can be considered during the design stage. For this system there are several issues to research, like the digital human modeling technology, the definition of interactions between human and product, the simulation of human motion when using the product, and the bio-mechanical analysis of human, etc. This paper introduces how to construct the kinematical structure of the digital human model. For our digital human model H-ANIM, the international specification of humanoid animation is referenced. And we added the skeleton geometry and the skin surfaces to our model. And it can manipulate its joints by forward kinematics. Also the IKAN inverse kinematics algorithm is adopted to support the posture prediction of the digital human model in the product environment. All of these ideas are implemented using CAD API so that we can apply these functions to the current commercial CAD systems. In this manner, the human factor issues can be effectively taken into account at the early design phase and the costs of bio-mechanical evaluation will be significantly reduced.

• The Journal of the Korean bone and joint tumor society
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• v.12 no.2
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• pp.165-170
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• 2006

We reported a case of chondrosarcoma in proximal tibia in a 44-year-old man. MR images demonstrated a $3.5{\times}20$ cm sized bone tumor. In reconstruction of resected proximal tibia, we used the allograft bone and soft tissue defects were covered by medial gastrocnemius rotation flap and skin graft. There were no local recurrence and distant metastasis and any complication such as secondary infection, nonunion, metal failure at the time of the last follow-up. There was no limitation of knee motion through the appropriate rehabilitaion programs.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.25 no.3B
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• pp.529-540
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• 2000

This is paper presents the semantic based rate-control method which is based on very low bit rate video coding standards H.263 plus, applied on very low bit rate applications. Previous rate control methods control the generated bit rates by setting the optimum quantization parameters per macro block unit on frame. But, in this paper, we added the pre-processing algorithm, semantic region recognition and assignment of priority algorithm, to obtain the subjective quality enhancement. This work aims to improve the subjective quality of skin color region or face by using unimportant background region's bit resources.

• Journal of Biomedical Engineering Research
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• v.40 no.6
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• pp.230-234
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• 2019

Medical laser equipment using optical energy is used to surgery and treat diseases by destroying and removing tissue. Domestic laser equipment has been used steadily in the skin and cosmetics sectors and has been changed to radiate high-power energy in a wide range to shorten patient treatment time. However, side effects such as burns and damage of normal tissues occurred. To solve this problem, techniques for detecting lesions using an imaging device and selectively radiating the laser have been developed. In this study, we proposed an evaluation method to evaluate the safety and performance of target detection accuracy, laser irradiation accuracy and motion protection device technology derived from product analysis and investigation. Finally, the validity of the evaluation method was evaluated by evaluating the imaging device based laser equipment as the proposed evaluation method.