• 제어로봇시스템학회:학술대회논문집
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• 2003.10a
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• pp.942-947
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• 2003

An important signal processing problem in PVDF sensor is the restoration of surface information from electric sensing signals. The objectives of this research are to design a new texture sensing system and to develop a new signal processing algorithm for signals from the sensor to be tangibly displayed by tangible interface systems. The texture sensing system is designed to get surface information with high resolution and dynamic range. First, a PVDF sensor is made of piezoelectric polymer (polyvinylidene fluoride) strips molded in a silicon rubber and attached in a rigid cylinder body. The sensor is mounted to a scanning system for dynamic sensing. Secondly, a new signal processing algorithm is developed to restore surface information. The algorithm consists of the two-dimensional modeling of the sensor using an identification method and inverse filtering from sensing signals into estimated surface information. Finally the two-dimensional surface information can be experimentally reconstructed from sensing signals using the developed signal processing algorithm.

• Journal of Chest Surgery
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• v.36 no.10
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• pp.759-765
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• 2003

Truncus arteriosus with interrupted aortic arch is a very rare congenital cardiac anomaly that has an unfavorable natural course. We report a successful one-stage repair of truncus arteriosus with interrupted aortic arch through median sternotomy in a 25-day-old neonate weighing 3.1 kg. We reconstructed the aortic arch with direct side-to-end anastomosis between ascending and descending aortas. The right ventricular outflow reconstruction was performed with untreated autologous pericardial conduit without valve following Lecompte maneuver. The patient has been grown-up in good condition (25 ∼ 50 percentile of body weight) and shows the right ventricular outflow tract wide 1 year after the operation.

• The Journal of the Korean bone and joint tumor society
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• v.1 no.1
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• pp.105-112
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• 1995

Soft tissue sarcomas are malignant tumors that arise in the extraskeletal connective tissues of the body. And the clinical behavior of soft tissue sarcomas is characterized by a tendency to extensively invade surrounding soft tissues as well as early metastatic dissemination. Difficulties were encounted when soft tissue sarcomas invade the major vessels. There are a few reprots about the reconstruction of the major vessels after resection of soft tissue sarcomas. We have treated 3 cases of the soft tissue sarcomas involving the major artery. After marginal excision of the tumor mass, the involved major artery was reconstructed with Gortex artificial vessel graft and we could salvage the patient's extremity.

• Proceedings of the KOSOMBE Conference
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• v.1997 no.05
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• pp.88-91
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• 1997

One of the most significant feature of diagnostic ultrasonic instrument is to display information on the soft tissues in the body in real time. In this paper we carried out basic study on the digital moving image processing for tracing the movement of heart valves in echocardiograms. Digital moving image file was made from analog echocardiograms and it was remade as 256 gray-level images on each frame. The ROI(Region of interest) was placed on a heart valve region to process images efficiently. Images were processed by the use of image enhancement filters and morphology filters. The result shows that the processed images were more enhanced than original images. When a moving image is reconstructed by using these enhanced images, we can trace the movement of heart valves more easily. In this study we proposed the availability of the moving image reconstruction using enhancement images.

• Journal of International Society for Simulation Surgery
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• v.3 no.2
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• pp.77-79
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• 2016

Osteoma is one of the benign tumor that occurs on the bones all over the body. Mostly the simple excision is known to be enough. However, sometimes we encounter the troublesome situation where the osteoma is located in very challenging area, which results in the recurrence. 26 year female presented with the intractable intracranial osteoma. Given the disease entity of the osteoma, the simple excision would be enough or conservative management. But this osteoma turned out to be huge and recurrent in spite of the endoscopic resections, which causes the facial disappearance accompanied by the orbital vertical dystopia. Moreover, the patient's main concern was the pain. We performed the intracranial resection of the whole lesion and reconstructed the skull base and frontal bone as well as the part of the orbital wall. In order to restore the original bony anatomy, the 3D printing model was used based on the titanium mesh. I report this unusual case of the intractable intracranial huge osteoma. This report may be helpful for the other surgeons to make a decision on their similar cases in the future.

• The KSFM Journal of Fluid Machinery
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• v.14 no.5
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• pp.48-54
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• 2011

Structural modifications of a ship may cause a fatal accident such as sinking and wrecking of ship. Especially, barge ship can be easily reconstructed to load more bulk cargo. In this study, for a real accident case, change of mooring force due to structural modification was analyzed to evaluate accident risk. A two dimensional dynamic model for the barge ship was constructed to compute mooring forces with related to floating motion. The equation of motion was established in Matlab code and buoyancy was calculated by using direct integration of submerged volume. The results showed that wind force, current force, and mooring force after rebuilding was approximately 4.3 kN, 14 kN, 1,561 kN respectively. The maximum force of mooring force according to the length of mooring cable were 1,614 kN at 30 m of mooring cable. Thus, an arbitrary modification of ship lead instability and unreliable result so that illegal rebuilding of ship should be avoided.

• Journal of computational fluids engineering
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• v.17 no.1
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• pp.8-15
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• 2012

A code developed using the flux-difference splitting scheme on the hybrid Cartesian/immersed boundary method is applied to simulate three-dimensional internal waves. The material interface is regarded as a moving contact discontinuity and is captured on the basis of mass conservation without any additional treatment across the interface. Inviscid fluxes are estimated using the flux-difference splitting scheme for incompressible fluids of different density. The hybrid Cartesian/immersed boundary method is used to enforce the boundary condition for a moving three-dimensional body. Immersed boundary nodes are identified within an instantaneous fluid domain on the basis of edges crossing a boundary. The dependent variables are reconstructed at the immersed boundary nodes along local normal lines to provide the boundary condition for a discretized flow problem. The internal waves are simulated, which are generated by an pitching ellipsoid near an material interface. The effects of density ratio and location of the ellipsoid on internal waves are compared.

• Archives of Reconstructive Microsurgery
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• v.9 no.1
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• pp.56-61
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• 2000

Recommendable reconstructive surgery in the patient with thumb amputation through base of the first metacarpal bone is pollicization. Some patients who do not agree with harvest sound finger as a new thumb, we can consider other options as toe transplantation or osteoplastic thumb reconstruction for creating thumb. Toe transplantation to the thumb is effective procedure in the amputation of distal to metacarpal shaft, it is rarely indicated in the cases of proximal to base of the first metacarpal bone. We performed three cases of modified osteoplastic thumb reconstruction with free vascularized rib that combined with scapular free flap or radial forearm flap. The length of transplanted rib ranged from 7~11cm, the donor vessels are posterior intercostal artery and vein which anastomosed to radial artery. The grafted rib wrapped with additional free flap for creating new thumb. Result of that procedure was not much encouraging, aesthetic appearance and mobility of thumb were not so satisfactory but reconstructed thumb gave improvement of the hand function without sacrificing toe or other digit. That gave reasonable stability for powerful side pinch and three pod pinch and opposable thumb with normal carpo-metacarpal joint motion that can give much function to the thumb absent hand. In spite of those disadvantages, thumb reconstruction with rib transfer can be useful for patients who do not want to lose another part of the body for creating thumb in basal amputation of the thumb metacarpal.

• Maxillofacial Plastic and Reconstructive Surgery
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• v.19 no.1
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• pp.45-54
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• 1997

The purpose of this investigation was to determine the biomechanical property of calvarial defects reconstructed using toothash, plaster and tooth-plaster mixture. Full-thickness bony defects were made on the rat calvaria with size of $10mm{\times}10mm$. Group 1 was filled with toothash only, group 2 : toothash-plaster mixture, and group 3 : plaster only. The defects were allowed to heal for 12 and 20 weeks before killing the animals. Light microscopic examinations vas taken after 12 week after operation. The hardness was evaluated for test of mechanical property. The following results were obtained : 1. In light microscopic examination 12 week after operation, there were no inflammatory and foreign body reaction. Implanted particles were resorbed gradually or united directly with newly formed bone. 2. In hardness test, the hardness of newly formed bone was lower than that of normal bone and there was significant difference(P<0.01). The site of new bone formation has enough hardness to resist the mechanical stress. These results suggest that toothash and plaster are biocompatible and osteoconductive material.

• Archives of Plastic Surgery
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• v.32 no.1
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• pp.24-28
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• 2005

Skull or facial bone defect causes cosmetic and functional problems. On going efforts were taken to reconstruct the craniofacial bone defect with autogenous bone or alloplastic materials. Between 2001 and 2003, we reconstructed 15 cases with small to large craniofacial bone defect using Hydroxyapatite paste($BoneSource^{(R)}$, Leibinger Corp., Dallas, TX, U.S.A) and calvarial bone graft. All patients were followed up by clinical examination and periodic radiographic studies for an average of 1.6 years (range, 6 months to 2 years and 6 months). One complication case was noted with $BoneSource^{(R)}$ exposure. Otherwise, there was no evidence of adverse healing, wound infection, foreign body reaction and seroma collection in other patients. Adequate 3-dimensional aesthetic restoration of calvarial contour was noted in each case. In conclusion, $Bonesource^{(R)}$ is relatively safe and rigid material for craniofacial bone defect and reasonable method for the reconstruction of craniofacial bone defects.