• 로봇학회논문지
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• 제6권3호
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• pp.220-229
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• 2011

This paper focuses on a development of an anthropomorphic robot hand. Human hand is able to dexterously grasp and manipulate various objects with not accurate and sufficient, but inaccurate and scarce information of target objects. In order to realize the ability of human hand, we develop a robot hand and introduce a control scheme for stable grasping by using only kinematic information. The developed anthropomorphic robot hand, KITECH Hand, has one thumb and three fingers. Each of them has 4 DOF and a soft hemispherical finger tip for flexible opposition and rolling on object surfaces. In addition to a thumb and finger, it has a palm module composed the non-slip pad to prevent slip phenomena between the object and palm. The introduced control scheme is a quitely simple based on the principle of virtual work, which consists of transposed Jacobian, joint angular position, and velocity obtained by joint angle measurements. During interaction between the robot hand and an object, the developed robot hand shows compliant grasping motions by the back-drivable characteristics of equipped actuator modules. To validate the feasibility of the developed robot hand and introduced control scheme, collective experiments are carried out with the developed robot hand, KITECH Hand.

• 한국공작기계학회논문집
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• 제14권4호
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• pp.81-88
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• 2005

This paper attempts to derive the dynamic model of handling tasks in finger robot which grasps stable and manipulates a rigid object with some dexterity. Firstly, a set of differential equation describing dynamics of the manipulators and object together with geometric constraint of tight area-contacts is formulated by Lagrange's equation. Secondly, the roblems of controlling both the forces of pressing object and the rotation angle of the object under the geometric constraints are discussed. The effect of geometric constraints of area-contacts between the link's end-effector and the object is analyzed and the model based on the differential-algebraic equations is presented. In this paper, the control method for dynamic stable grasping and enhancing dexterity in manipulating things is proposed. It is illustrated by computer simulation and the experiment that the control system gives the performance improvement in the dynamic stable grasping and nimble manipulating of the dual fingers robot with soft tips.

• Archives of Plastic Surgery
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• 제37권6호
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• pp.815-818
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• 2010

Purpose: Soft tissue chondroma is a rare benign tumor, found mainly on the palm and sole and grows slowly. Typically, mature hyaline cartilage is the dominant pathological feature. There are reports that assert soft tissue chondromas to be a cause of median nerve entrapment syndrome. However, this is the first case report showing soft tissue chondroma to be a cause of simultaneous median and ulnar neuropathy. Methods: A 62 year-old woman presented with chief complaints of numbness and hypoesthesia of her right palm for 4 to 5 years, and a palpable mass on her right palm that had been increasing in size slowly for 3 years. Physical examination revealed a firm, mobile, non-tender and about $3{\times}3\;cm^2$ sized mass in the center of the right palm. Electromyography showed entrapment neuropathy of the median and ulnar nerve. Ultrasonography showed an approximately $5.7\;cm^2$ mass below the flexor tendon of ring finger. Upon surgical excision, a $3{\times}3\;cm^2$ mass attached to the flexor digitorum profundus of ring finger and redness and hypertrophy of both the median and ulnar nerve were discovered. Mass excision was performed gently and the specimen was referred for histopathologic study. Mass excision resulted in median and ulnar nerve release. Results: The pathology report confirmed the mass to be a soft tissue chondroma with mature hyaline cartilage. The patient exhibited post-operative improvement of her symptoms and did not show any complications. Conclusion: This is the first case report showing soft tissue chondroma to be a cause of simultaneous median and ulnar neuropathy.

• 대한치과보철학회지
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• 제21권1호
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• pp.59-66
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• 1983

Distal extension partial dentures are supported by both the relatively rigid teeth and the resilient mucosa. So impression techniques of residual alveolar ridge in case of distal extension partial denture have particular importance in order to broad distribution of the masticatory force. McLean recognized the need for recording the tissues supporting distal extension partial denture base in functional form to equalize the resilient and non-resilient support, and this was called functional impression. Many investigators proposed various techniques of the functional impression for a distal extension partial denture, but only a little studies were performed about displacement of soft tissue under distal extension partial denture base. The purpose of this study is to investigate the amount of vertical displacement of the soft tissue under distal extension partial denture base by different functional impression techniques. Impression techniques used were Z.O.P. Impression, Selective Tissue Placement Impression, Functional Relining Impression. Measurement of the vertical displacement of soft tissue were made with Depth Gauge and Measuring Platform. A Anatomic Impression was used as a control. The results were tested statistically using 3 way ANOVA and Scheffe test. The followings were the results obtained from this study. 1. The greatest amount of soft tissue displacement was observed in the center of the retromolar pad. 2. No significant differences were found between the crest of alveolar ridge and the buccal shelf area. 3. The greatest soft tissue displacement was observed in Functional Relining Impression using Iowa wax, and the least displacement was observed in Selective Tissue Placement Impression using murcaptan rubber base. 4. No significant differences were found between finger pressure and biting pressure in Z.O.P. Impression, but greater displacement was observed by biting pressure than finger pressure in Functional Reling Impression.

• 대한산업공학회지
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• 제42권1호
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• pp.57-64
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• 2016

Pen-based interaction is universally available on smart devices and especially on Tablet PCs. Previous studies compared various input methods like fingers, a mouse or a stylus pen on PCs or on a touchscreen based devices such as smart phones. At the same time, various soft keyboard applications are being developed on application stores of smart devices. However, these previous studies did not suggest which one is a suitable keyboard application for Tablet PCs when users perform a certain interaction as input type. In this study, we compared two types of input methods (finger and pen) and three types of soft keyboard applications (QWERTY, Gesture and Swype) in a Tablet PC using performance measurements (accuracy and input speed) and discussed what types of applications showed better performance with each interaction on tablet PC. From these results, recommendations for the keyboard types depending on the input methods on tablet PCs were developed.

• Archives of Reconstructive Microsurgery
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• 제6권1호
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• pp.87-95
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• 1997

Traumatic injury to the hand often leads to soft tissue defects with exposed tendons, bones, or joints. Though many new flap have been introduced, the choice of flap that would be best for the patient depends on such factors as the site, size, and degree of wounds. Additionally the selected surgical method should be yielded cosmetic and functional superiority by the one-staged reconstruction. In our experience, small to medium sized soft tissue defect with bone and tendon exposure of hand can be resurfaced with an arterialized venous free flap from the volar aspect of distal forearm. Wide and deep defects of the hand can be covered with a sensory cutaneous free flap such as the medial plantar free flap, dorsalis pedis free flap, and radial forearm free flap. Specialized flap such as wrap-around flap, toe-to-finger transfer, onychocutaneous free flap can be used for the recontruction of defect on the thumb and finger. Based on the above considerations and our clinical experience of 60 free flap cases of the hand, the various methods for the proper repair of soft tissue defects of the hand are described. And we obtained satisfactory functional and cosmetic results with 95% success rate of free flap.

• KSII Transactions on Internet and Information Systems (TIIS)
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• 제8권5호
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• pp.1766-1784
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• 2014

Finger vein images contain rich oriented features. Local line binary pattern (LLBP) is a good oriented feature representation method extended from local binary pattern (LBP), but it is limited in that it can only extract horizontal and vertical line patterns, so effective information in an image may not be exploited and fully utilized. In this paper, an orientation-selectable LLBP method, called generalized local line binary pattern (GLLBP), is proposed for finger vein recognition. GLLBP extends LLBP for line pattern extraction into any orientation. To effectually improve the matching accuracy, the soft power metric is employed to calculate the matching score. Furthermore, to fully utilize the oriented features in an image, the matching scores from the line patterns with the best discriminative ability are fused using the Hamacher rule to achieve the final matching score for the last recognition. Experimental results on our database, MMCBNU_6000, show that the proposed method performs much better than state-of-the-art algorithms that use the oriented features and local features, such as LBP, LLBP, Gabor filter, steerable filter and local direction code (LDC).

• Journal of Information Processing Systems
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• 제18권5호
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• pp.688-700
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• 2022

A composite bionic soft gripper integrated with electromagnets and magneto-active elastomers is designed by combining the structure of the human hand and the snake's behavior of enhancing friction by actively adjusting the scales. A silicon-based polymer containing magnetized hard magnetic particles is proposed as a soft finger, and it can be reversibly bent by adjusting the magnetic field. Experiments show that the length, width, and height of rectangular soft fingers and the volume ratio of neodymium-iron-boron have different effects on bending angle. The flexible fingers with 20 vol% are the most efficient, which can bend to 90° when the magnetic field is 22 mT. The flexible gripper with four fingers can pick up 10.51 g of objects at the magnetic field of 105 mT. In addition, this composite bionic soft gripper has excellent magnetron performance, and it can change surface like snakes and operate like human hands. This research may help develop soft devices for magnetic field control and try to provide new solutions for soft grasping.

• Archives of Reconstructive Microsurgery
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• 제18권1호
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• pp.35-39
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• 2009

Purpose: Various techniques have been attempted for design of the flaps. However, there are some disadvantages. They have thin, pliable, and two dimensional methods. The aim of this study is to report usefulness of polyurethane foam dressing materials for three dimensional design of the digital island flap. Methods: From June of 2007 to september of 2008, 10 patients received digital island flap surgery for soft tissue defect of the finger. After minimal debridement of the wound, size and shape of the defect were measured using polyurethane foam. We used Medifoam-$5^{(R)}$ And then, designed this inset the wound. The flap was designed on the donor site with a arterial pedicle as the central axis according to size and shape. A full thickness skin graft from the groin is applied on the flap donor defect and secured with a tieover bolster dressing. Results: Reviewing sizes of the flaps, the length and width of flaps ranged from 1.5 to 3.3 cm and 1.0 to 2.5 cm. The PACS(Picture Archiving Communication System) program allows identification of the donor depth of finger. The distance for the soft tissue ranged from 4.3 mm to 6.7 mm. Mean depth of donor site was 5.3${\pm}$0.6 mm. Also, the thickness of Medifoam-$5^{(R)}$ ranged nearly 5 mm. On flap insetting, full-thickness skin graft was necessary. We did not experience any problems in the recipient site size either, regardless of the extended flaps. Conclusion: Polyurethane foam has many advantages over the more conventional templates. Refinements in flap design and surgical technique resulted in favorable functional and cosmetic results. Especially, for beginner, Polyurethane foam dressing material is a simple and safe tool and therefore is an excellent choice for design of the island flap.

• Archives of Plastic Surgery
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• 제42권3호
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• pp.334-340
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• 2015

Background Full-thickness skin grafts (FTSGs) are generally considered unreliable for coverage of full-thickness finger defects with bone or tendon exposure, and there are few clinical reports of its use in this context. However, animal studies have shown that an FTSG can survive over an avascular area ranging up to 12 mm in diameter. In our experience, the width of the exposed bones or tendons in full-thickness finger defects is <7 mm. Therefore, we covered the bone- or tendon-exposed defects of 16 fingers of 10 patients with FTSGs. Methods The surgical objectives were healthy granulation tissue formation in the wound bed, marginal de-epithelization of the normal skin surrounding the defect, preservation of the subdermal plexus of the central graft, and partial excision of the dermis along the graft margin. The donor site was the mastoid for small defects and the groin for large defects. Results Most of the grafts (15 of 16 fingers) survived without significant surgical complications and achieved satisfactory functional and aesthetic results. Minor complications included partial graft loss in one patient, a minimal extension deformity in two patients, a depression deformity in one patient, and mild hyperpigmentation in four patients. Conclusions We observed excellent graft survival with this method with no additional surgical injury of the normal finger, satisfactory functional and aesthetic outcomes, and no need for secondary debulking procedures. Potential disadvantages include an insufficient volume of soft tissue and graft hyperpigmentation. Therefore, FTSGs may be an option for treatment of full-thickness finger defects with bone or tendon exposure.