• The Journal of the Korean dental association
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• v.51 no.12
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• pp.650-657
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• 2013

The aim of this study was to achieve healing of Peri-implantitis defects and hard tissue augmentation using a bovine-derived bone mineral on the defect site. Two patients were treated with the surgical approach. With a full muco-periosteal flap elevation, the implant surfaces were exposed and granulation tissue removed around the implant and between the threads. Each surface of the contaminated implant was prepared with the air-abrasive device(PerioFlow$^{(R)}$) for decontamination. Bovine-derived bone mineral(Bio-Oss collagen$^{(R)}$) was then used to fill the defects and muco-periosteal flaps sutured to achieve transmucosal healing. Radiographs and clinical photographs were taken before and after 6 months of healing and an estimate of bone fill was assessed. Within the limits of the present case report, a surgical approach in treatment of peri-implantitis defects using a collagen form of bovine bone mineral was visited. Although limited, the two cases showed the stability and biocompatibility of a bovine-derived bone mineral and effectiveness of air-abrasive device(PerioFlow$^{(R)}$) as a decontamination method.

• Maxillofacial Plastic and Reconstructive Surgery
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• v.22 no.4
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• pp.449-453
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• 2000

Soft tissue expansion is widely used technique in oral & maxillofacial reconstruction and provide new method of reconstruction in posttraumatic alopecia, post burn, wide scar, congenital deformity, benign tumor, tattoo, etc. Expanded tissue flaps have the advantage of increased vascularity, proximity to the defect, and similarity of color and texture. They also preclude the need to advance flaps from distant sites. Tissue expansion can be used to form a well vascularized cavity to accomodate and nourish bone grafts. The following report describes the uses of tissue expanders by allowing bone grafting to correct both soft and bony defects of mandibular region

• Proceedings of the IEEK Conference
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• 2002.07a
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• pp.176-179
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• 2002

In recent years, an increasing amount of computer network research has focused on the problem of cluster system in order to achieve higher performance and lower cost. The load unbalance is the major defect that reduces performance of a cluster system that uses parallel program in a form of SPMD (Single Program Multiple Data). Also, the load unbalance is a problem of MPP (Massive Parallel Processors), and distributed system. The cluster system is a loosely-coupled distributed system, therefore, it has higher communication overhead than MPP. Dynamic load balancing can solve the load unbalance problem of cluster system and reduce its communication cost. The cluster systems considered in this paper consist of P heterogeneous nodes connected by a switch-based network. The master node can predict the average execution time of tasks for each slave node based on the information from the corresponding slave node. Then, the master node redistributes remaining tasks to each node considering the predicted execution time and the communication overhead for task migration. The proposed dynamic load balancing uses execution time prediction to optimize the task redistribution. The various performance factors such as node number, task number, and communication cost are considered to improve the performance of cluster system. From the simulation results, we verified the effectiveness of the proposed dynamic load balancing algorithm.

• Proceedings of the Korean Society for Technology of Plasticity Conference
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• 2001.10a
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• pp.305-308
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• 2001

Powder injection molding (PIM) uses the shaping advantage of injection molding but is applicable to metals and ceramics. This process combines a small quantity of polymer with an inorganic powder to form a feedstock that can be molded. After shaping, the polymeric binder is extracted and the powder is sintered often to near-theoretical densities. Accordingly, PIM delivers structural materials in a shaping technology previously restricted to polymers. The process overcomes the shape limitations of traditional powder compaction, the costs of machining, the productivity limits of isostatic pressing and slip casting, and the defect and tolerance limitations of casting. The 17-4 PH stainless steel powders with average diameter of $10{\mu}m$ were injection-molded into flat tensile specimens. Sintering of the compacts was carried out at the various temperatures ranging from 900 to $1350^{\circ}C$. Sintering behavior of the compacts and tensile properties of sintered specimens were investigated.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2007.11a
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• pp.216-220
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• 2007

By virtue of recent economic development and cultural progress, the desires willing to enjoy a plentiful leisure life among people are on enlarging, then according to this, the demand for a grand performance hall where various cultural events are achievable is also on increasing. However, since the grand performance hall has its characteristics that must accommodate various forms of performances likely from lecture, meeting activity to recital, and because the clearness of sound is on emphasizing, and also it requires the repletion or abundance of sound simultaneously, it could be said that from the designing stage, a sufficient examination and plan with regard to the architectural acoustics design is indispensable. On such view point, for the object of the grand performance hall under actually planning to build, this Study is attempting to compare analyze on Room Acoustics Characteristics using computer simulation from the stage of design. It is considered that the material analyzed in such way could be reflected in maximum basis to the design of the performance hall that minimizes the acoustic defect at the designing step, and also it could be utilized as the useful material at the time of design for a similar form of performance hall in the future.

• Journal of Veterinary Clinics
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• v.21 no.2
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• pp.219-228
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• 2004

Heart diseases related to conduction system can be occurred by primary defects in conduction system and by secondary to morphological heart diseases or drug toxicities. Multiple molecular defects responsible for arrhythmogenesis, including mutations in ion channels, cytoplasmic ion-channel-interacting proteins, gap-junction proteins, transcription factors and a kinase subunit, were found to be associated with the aetiology of primary cardiac conduction defects, especially inherited form. Despite a big progress in unveiling human arrhythmogenesis, conduction defects in dog has not been well studied except sudden death syndrome in German shepherd. In this review, molecular genetics in cardiac arrhythmogenesis, inherited human diseases associated with conduction defects and similar diseases in dogs will be discussed.

• Journal of Chest Surgery
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• v.18 no.2
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• pp.273-278
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• 1985

The case of a patient with abnormal position of the atrial septum resulting in a left atrium with two atrioventricular valves and a disconnected right atrium is presented with review of related articles. Anatomic details showed atrial situs solitus and a left sided cardiac apex. The right atrium received both venae cavae and a coronary sinus. No AV valve was found in the right atrium, and the floor of this chamber was placed above the posterior wall of right ventricular chamber. The atrial septum with secundum ASD was displaced to right anteriorly at its lower portion and inserted to right of tricuspid annulus. The tricuspid and mitral valve configuration was that of so-called partial ECD, i.e. mitral cleft with large anterior mitral leaflets. The ventricular septum was intact and both ventricular chambers were equally well developed with normal relationships. Surgical repair of this anomaly was performed by resecting the abnormally positioned lower part of the atrial septum, repairing the cleft of the anterior mitral leaflet, and septating the atrium for diverting the systemic and pulmonary venous blood to RV and LV, respectively.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.30 no.5
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• pp.276-283
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• 2017

A polysilicon-based metal-semiconductor-metal (MSM) photodetector was fabricated by means of our new methods. Its photoresponse characteristics were analyzed to see if it could be applied to a sensor system. The processes on which this study focused were an alloy-annealing process to form metal-polysilicon contacts, a post-annealing process for better light absorption of as-deposited polysilicon, and a passivation process for lowering defect density in polysilicon. When the alloy annealing was achieved at about $400^{\circ}C$, metal-polysilicon Schottky contacts sustained a stable potential barrier, decreasing the dark current. For better surface morphology of polysilicon, rapid thermal annealing (RTA) or furnace annealing at around $900^{\circ}C$ was suitable as a post-annealing process, because it supplied polysilicon layers with a smoother surface and a proper grain size for photon absorption. For the passivation of defects in polysilicon, hydrogen-ion implantation was chosen, because it is easy to implant hydrogen into the polysilicon. MSM photodetectors based on the suggested processes showed a higher sensitivity for photocurrent detection and a stable Schottky contact barrier to lower the dark current and are therefore applicable to sensor systems.

• Journal of KIISE:Software and Applications
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• v.28 no.1
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• pp.26-30
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• 2001

Multipopulation Genetic Algorithm(MPGA) is the modified form of Genetic Algorithm(GA), which was devised for covering for overing the defect of general GA. The core of MPGA is said to be the migration method. The fitness-based migration method and the random migration method are currently used. The random migration method is more general than the other because it keeps the diversity of the population. In this paper, a new migration method is suggested. This method has a merit that it can improve the speed of conergence, compared to the general migration method. This method is compared with the general migration method.

• Transactions of the Korean Society of Machine Tool Engineers
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• v.14 no.3
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• pp.96-102
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• 2005

Acoustic Emission(AE) technique has been applied to not only material characterization evaluation but also on-line monitoring of the structural integrity. The AE source location technique is very important to identify the source, such as crack, leak detection. Since the AE waveforms obtained from sensors are very difficult to distinguish the defect signals, therefore, it is necessary to consider the signal analysis of the transient wave-form. In this study, we have divided the region of interest into a set finite elements, and calculated the arrival time differences between sensors by using the velocities at every degree from 0 to 90. A new technique for the source location of acoustic emission in fiberboard plates has been studied by introducing Wavelet Transform(WT) do-noising technique. WT is a powerful tool for processing transient signals with temporally varying spectra. If the WT de-noising was employed, we could successfully filter out the errors of source location in fiberboard plates by arrival time difference method. The accuracy of source location appeared to be significantly improved.