• Journal of the Korean Institute of Telematics and Electronics B
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• v.32B no.11
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• pp.1445-1454
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• 1995

In this study, we have developed a prototype of the automatic defects detection system for capsule inspection using the computer vision techniques. The subjects for inspection are empty hard capsules of various sizes which are made of gelatine. To inspect both sides of a capsule, 2-stage recognition is performed. Features we have used are various lengths of a capsule, area, linearity, symmetricity, head curvature and so on. Decision making is performed based on average value which is computed from 20 good capsules in training and permission bounds in factories. Most of time-consuming process for feature extraction is computed by hardware to meet the inspection speed of more than 20 capsules/sec. The main logic for control and arithmetic computation is implemented using EPLD for the sake of easy change of design and reduction in time for developement. As a result of experiment, defects on size or contour of binary images are detected over 95%. Because of dead zone in imaging system, detection ratio of defects on surface, such as bad joint, chip, speck, etc, is lower than the former case. In this case, detection ratio is 50-85%. Defects such as collet pinch and mashed cap/body seldom appear in binary image, and detection ratio is very low. So we have to process the gray-level image directly in partial region.

• Archives of Reconstructive Microsurgery
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• v.20 no.2
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• pp.126-131
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• 2011

Purpose: The subcutaneous pocket graft of the thumb tip amputation across or proximal to the lunula is chosen in case of impossible microvascular anastomosis and in patient who strongly desired to preserve the thumb tip after failed replantation. Materials and Methods: Two patients who underwent a subcutaneous pocket graft for a thumb tip reconstruction between August 2008 and November 2009 were reviewed retrospectively. They were all males with a mean age at the time of surgery of 48 years and had sustained complete thumb tip amputations across or proximal to the lunula. In one case, the microsurgical replantation was not feasible and the other one revealed arterial insufficiency at the 7th day after microsurgical replantation. Results: Authors had experienced 2 cases of flaps which survived completely. The results of sensibility was good, the range of motion at interphalangeal joint and tip to tip pinch was acceptable and color mismatch and loss of thumb finger nail was unacceptable after more than 1 year follow up with conventional successful thumb tip replantation. Conclusion: The subcutaneous pocket graft could be chosen in thumb tip amputation in case of impossible microvascular anastomosis as well as who strongly desires to preserve thumb tip after failed replantation.

• Archives of Reconstructive Microsurgery
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• v.15 no.2
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• pp.117-122
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• 2006

The function of the thumb is critical to overall hand function. The thumb enables motions such as pinch, grip, fine manipulation and allows to circumduction and opposition. It's loss is a serious problem not only from cosmetic point of view but also functional. Therefore, we should make every effort on thumb reconstruction. Many methods of thumb reconstruction from simple osteoplasty to complex microsurgical reconstruction have been reported. We should understand merits and demerits of each method and choose proper method on case by case. When both hands are injured and there is no option but to amputate one hand and the thumb of another hand is lost, spare part flap from the thumb of the amputated hand to another hand can solve cosmetic problem, functional problem and donor morbidity. We report a case of amputated thumb which has been reconstructed with amputated ring finger of the contralateral hand using spare part flap concept.

• Korean Journal of Materials Research
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• v.13 no.12
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• pp.769-774
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• 2003

In this paper, we report on the DC characteristics of the AlGaN/GaN HFETs using physical models on piezoelectric and thermal effects. Employing the models was found to be essential for a realistic prediction of the DC current-voltage characteristics of the AlGaN/GaN HFETs. Though use of the implementation of the physical models, peak drain current, transconductance, pinch-off voltage, and most importantly, the negative slope in the current were accurately predicted. The importance of the heat sink effect was demonstrated by the comparison of the DC characteristics of AlGaN/GaN HFETs fabricated from different substrates including sapphire, Si and SiC. Highest peak current was achieved from the device with SiC by an effective suppression of heat sink effect.

• Korean Journal of Pharmacognosy
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• v.36 no.4 s.143
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• pp.299-304
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• 2005

This study examined the antinociceptive properties of GCSB-5, a herbal formulation consisting of 6 Oriental herbs (Ledebouriellae Radix, Achyranthis Radix, Acanthopanacis Cortex, Cibotii Rhizoma, Glycine Semen, and Eucommiae Cortex) that are used in traditional medicine to treat various bone disorders, mainly of which involve analgesic processes. Peripheral and central analgesic models were established in experimental animals in order to evaluate the antinociceptive effects of the agent. GCSB-5 significantly inhibited the number of acetic-induced writhing (33.3%-34.3% inhibition at 100-600 mg/kg) but increased the pain threshold (38.0% increase at 300 mg/kg) in the Randall-Selitto test. However, GCSB-5 had no effect on the hot plate-induced nociception and hyperalgesia from the tail-pinch method. These results suggest that the antinociceptive effect of GCSB-5 may be mediated via peripheral mechanisms.

• Archives of Plastic Surgery
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• v.45 no.2
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• pp.158-164
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• 2018

Background During breast augmentation, the transaxillary approach provides the advantage of allowing the mammary prosthesis to be placed through incisions that are remote from the breast itself, thereby reducing the visibility of postoperative scars. For patients experiencing capsular contracture who do not want additional scars, the previous transaxillary scar can be used for site change and implant exchange. Methods This study analyzed 17 patients (34 breasts) with submuscular breast implants with grade III-IV capsular contracture who received treatment from 2010 to 2015. The mean age of the patients was 29 years (range, 20-38 years). The inclusion criterion was a pinch test of more than 3 cm at the upper pole of the breast. Previous axillary scars were used to expose the pectoralis fascia, and submuscular breast implants were removed carefully. The dissection underneath the pectoralis fascia was performed with endoscopic assistance, using electrocautery under direct visualization. Results The mean follow-up period was 14 months (range, 6-24 months). The entire dissection plane was changed from the submuscular plane to the subfascial plane. Round textured gel implants were used, with a mean implant size of 220 mL (range, 160-300 mL). Two patients developed grade II capsular contracture. There were no cases of malposition or asymmetry. Three patients complained of minor implant palpability. None of the patients required additional surgery. Conclusions Endoscopic subfascial conversion may be an effective technique for treating capsular contracture and avoiding scarring of the breast in selected patients.

• Journal of Institute of Control, Robotics and Systems
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• v.16 no.9
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• pp.833-839
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• 2010

In this paper, a novel 1 DOF hand rehabilitation robot is proposed in consideration of ADL training for stroke patients. To perform several ADL trainings, the proposed robot can move the thumb part and the part of 4 fingers simultaneously and realize the full ROM (Range of Motion) in grasp. Based on these characteristics, the proposed robot realizes several types of grasp such as cylindrical grasp, lateral grasp, and pinch grasp by using a passive revolute joint that can change the thumb movement direction. The movement of the thumb is driven by a cable mechanism and the part of 4 fingers is moved by a four-bar linkage mechanism.

• Proceedings of the Korea Water Resources Association Conference
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• 2005.09b
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• pp.951-951
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• 2005

The characteristics of Boussinesq starting forced plumes were investigated in this study. Two distinct periods in the transient plume penetration were identified, namely the Period of Flow Development (PFD) and Period of Developed Flow (PDF). PFD refers to the time period whereby the penetration rate is governed by the complex vortex dynamics initiated by the exit conditions that can include vortex coalescence, vortex leapfrogging, pinching off of the head vortex from the trailing stem and the eventual reconnection. The pinch-off and reconnection leads to an overshoot of the plume front which is a common observation reported in previous studies. The penetration rate in PDF is more predictable and depends on the continuous feeding of buoyancy and momentum into the head vortex by the trailing buoyant-jet stem. Similarity solutions are developed for PDF to describe the temporal variation of the penetration rate, by incorporating the behavior of an isolated buoyant vortex ring and recent laboratory results on the trailing buoyant jet. In particular, the variations of velocity ratios between the head vortex and trailing buoyant jet are analytically computed. To verify the similarity solutions, experiments were conducted on vertical starting forced plumes using planar laser induced fluorescence (PLIF).

• Journal of Welding and Joining
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• v.15 no.5
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• pp.92-103
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• 1997

The purpose of this study is to improve the wear resistance and hardness of Al alloy by making a formation of the thick surface hardening layers. The thick surface hardening layers were formed by PTAW(Plasma Transferred Arc Welding), with the addition of metal powders (Cu), ceramics powders (NbC, TiC), and mixture powders (Cu+NbC) in Al alloy (A1050, A5083). Mechanical properties of overlaid layers (wear resistance, hardness) were investigated in relation to the microstructure. The results obtained are summarized as follows: The depth of penetration was increased with increasing powder feeding rate. It is considered that these increase were due to the thermal pinch effect by the addition of powders, especially, for the Cu powders, were due to the heat of reaction with the matrix. The hardness and wear resistance of overlaid layers were improved with increasing powder feeding rate. For the Cu powders, it is considered that these increase were due to the increase of the formation of ${\theta}(CuAl_2)$ phase with increasing feeding rate of Cu powers.

• The Journal of Korea Robotics Society
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• v.17 no.4
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• pp.484-492
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• 2022

This paper presents a simple and robust under-actuated robotic finger mechanism that enables self-adaptive grip, fingertip pinch, and caging grasp functions. In order to perform daily activities using hands, the fingers should be able to perform adaptive gripping and pinching motion, and the caging grasp function is required to realize natural gripping motions and improve grip reliability. However, general commercial prosthetic hands cannot implement all three functions because they use under-actuation mechanism and simple mechanical structure to achieve light-weight and high robustness characteristic. In this paper, new mechanism is proposed that maintains structural simplicity and implements all the three finger functions with simple one degree-of-freedom control through a combination of a four-bar linkage mechanism and a wire-driven mechanism. The basic structure and operating principle of the proposed finger mechanism were explained, and simulation and experiments using the prototype were conducted to verify the gripping performance of the proposed finger mechanism.