• The Journal of the Korean bone and joint tumor society
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• v.19 no.2
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• pp.64-68
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• 2013

Extraskeletal chondroma is a benign soft tissue tumor which is composed of hyaline cartilage but arises from the fibrous stroma rather than from mature cartilaginous or osseous tissue. Extraskeletal chondroma is relatively rare and occurs most frequently in the soft tissue around the joints of hands and feet. We present one case of extraskeletal chondroma in a finger of a young woman.

• Smart Media Journal
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• v.8 no.4
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• pp.53-57
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• 2019

In this paper, we propose a flex sensor-based data glove to track the movements of human fingers for virtual reality education. By putting flex sensors and utilizing an accelerometer, this data glove allows people to enjoy applications for virtual reality (VR) or augmented reality (AR). With the maximum and minimum values of the flex sensor at each finger joint, it determines an angle corresponding to the bending value of the flex sensor. It tracks the movements of fingers and hand gestures with respect to the angle values at finger joints. In order to prove the effectiveness of the proposed data glove, we implemented a VR classroom application.

• Proceedings of the KSME Conference
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• 2008.11a
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• pp.1588-1593
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• 2008

This paper describes a real-time isometric pinch force prediction algorithm from surface electromyogram (sEMG) using multilayer perceptron (MLP) for human robot interactive applications. The activities of seven muscles which are observable from surface electrodes and also related to the movements of the thumb and index finger joints were recorded during pinch force experiments. For the successful implementation of the real-time prediction algorithm, an off-line analysis was performed using the recorded activities. Four muscles were selected for the force prediction by using the Fisher linear discriminant analysis among seven muscles, and the four muscle activities provided effective information for mapping sEMG to the pinch force. The MLP structure was designed to make training efficient and to avoid both under- and over-fitting problems. The pinch force prediction algorithm was tested on five volunteers and the results were evaluated using two criteria: normalized root mean squared error (NRMSE) and correlation (CORR). The training time for the subjects was only 2 min 29 sec, but the prediction results were successful with NRMSE = 0.112 ${\pm}$ 0.082 and CORR = 0.932 ${\pm}$ 0.058. These results imply that the proposed algorithm is useful to measure the produced pinch force without force sensors in real-time. The possible applications include controlling bionic finger robot systems to overcome finger paralysis or amputation.

• Journal of the Korean Orthopaedic Association
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• v.55 no.6
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• pp.457-471
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• 2020

Fingers are body parts with a complex structure and essential functions that are the most prone to trauma. The principle of treatment for finger fractures is to determine the balance between obtaining stable fracture fixation and early joint movement. Despite proper treatment, there are many cases of functional and cosmetic problems caused by stiffness or deformation as complications. This review article introduces the latest knowledge in the treatment of finger fractures focusing on fractures and dislocations around the interphalangeal joints, including joint surface damage, which is difficult to treat and leads to poor results. This article consists of fracture cases and describes the methods and solutions to address these complications.

• The Journal of Korea Robotics Society
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• v.17 no.3
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• pp.322-333
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• 2022

The Avatar robot, which is one of the teleoperation robots, aims to enable users to feel the robot as a part of the body to intuitively and naturally perform various tasks. Considering the purpose of the avatar robot, an end-effector identical to a human hand is advantageous, but a robotic hand with human hand level performance has not yet been developed. In this paper we propose a new 3-finger robotic hand with human-avatar hand posture mapping algorithm which were integrated with TOCABI-AVATAR, one of the teleoperation system. Due to the flexible rolling contact joints and tendon driven mechanism applied to the finger, the finger could implement adaptive grasping and absorb the impact force caused by unexpected contacts. In addition, human-avatar hand mapping algorithm using five calibration hand postures propose to compensate physical differences between operators. Using the TOCABI-AVATAR system with the robotic hands and mapping algorithm, the operator can perform 13 out of 16 hand postures of grasping taxonomy and 4 gestures. In addition, using the system, we participated in the ANA AVATAR XPRIZE Semi-final and successfully performed three scenarios which including various social interactions as well as object manipulation.

• Archives of Reconstructive Microsurgery
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• v.9 no.2
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• pp.103-109
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• 2000

Purpose : We performed this study in order to analyze the clinical results of functioning gracilis musculocutaneous free flap transplantation for reconstructon of hand function in cases of Volkmann's ischemic contracture and massive soft tissue injury of forearm. Materials and methods : 18 cases were reviewed with 5 yeas of mean follow up period. We evaluated total active motion of the finger joints and wrist, pinch and grip strength. Results : The flap were survived in 17 cases and 1 case was failed due to infection. The sum of active motion of finger joints(TAM) was improved from 0 to $173.8^{\circ}$. The average grip and pinch strength was improved from 0 kg to $2.7{\pm}2.1kg$ and from 0 kg to $2.4{\pm}1.6kg$. Conclusion : The results in most cases were acceptable in relatively long term follow-up. It may be an option for reconstruction of hand function in cases of Volkmann's ischemic contracture and traumatic upper extremity injury.

• Journal of Convergence for Information Technology
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• v.10 no.6
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• pp.19-27
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• 2020

In this study, Developing high resolution camera and Social Network Service sharing image can be easily getting images, it cause about taking fingerprints to easy from images. So I present solution about prevent to taking fingerprints. this technology is develop python using to opencv, blur libraries. First of all 'Hand Key point Detection' algorithm is used to locate the hand in the image. Using this algorithm can be find finger joints that can be protected while minimizing damage in the original image by using the coordinates of separate blurring the area of fingerprints in the image. from now on the development of accurate finger tracking algorithms, fingerprints will be protected by using technology as an internal option for smartphone camera apps from high resolution images.

• Journal of the Korean Institute of Intelligent Systems
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• v.17 no.7
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• pp.862-868
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• 2007

The planar motion of the index finger in general human hands is usually implemented by the actuation of three joints. This task requires a technique to determine the joint combination for each fingertip position which is well-known as the inverse kinematics problem in robotics. Especially, it is an essential work for grasping and manipulation tasks by robotic and humanoid fingers. In this paper, an intelligent neural learning scheme for solving such inverse kinematics is presented. Specifically, a multi-layered neural network is utilized for effective inverse kinematics, where a dynamic neural learning algorithm is employed for fast learning. Also, a bio-mimetic feature of general human fingers is incorporated to the learning scheme. The usefulness of the proposed approach is verified by simulations.

• Archives of Plastic Surgery
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• v.50 no.2
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• pp.177-181
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• 2023

Digital extensor hypoplasia (DEH) is a rare malformation that presents with loss of active finger extension at the metacarpophalangeal (MCP) joints. Descriptions of optimal treatment and outcomes in this population are sparse. We describe successful operative treatment of a child with DEH involving the extensor digitorum communis, extensor digiti minimi, and the extensor indicis proprius tendons. The 5-year-old male patient was referred for severe limitation on bilateral finger extension since birth. He had been previously diagnosed with arthrogryposis and managed conservatively. Due to lack of improvement, magnetic resonance imaging was done evidencing hypoplasia/aplasia of the extensor tendons. The patient underwent successful tendon transfers using extensor carpi radialis longus to the common extensor tendons, and one hand required an additional tenolysis procedure. 2 years postoperatively, his MCP position and finger extension are markedly improved, and he is able to grip objects without limitation or difficulty. The patient returned to full activity without restriction.

• Journal of the Korean Society of Industry Convergence
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• v.18 no.3
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• pp.167-172
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• 2015

In this paper, we propose a new approach to design and control a smart gripper of robot system. A control method for flexible grasping a object in partially unknown environment was proposed, where a proximate sensor detecting the distance between the fingertip and object was used. Based on the proximate sensor signal the finger motion controller could plan the grasping process divided in three phases. The first step is scanning process which two first joints were moved to mid-position of the detected range by a state-variable feedback position controller, after the scanning was finished. The contact force of fingertip was then controlled using the detection sensor of the servo controller for finger joint control. The proposed grasping planning was tested on rectangular bar.