• Smart Structures and Systems
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• v.15 no.3
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• pp.555-576
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• 2015

The large number of long-span bridges constructed in China motivates the applications of structural health monitoring (SHM) technology. Many bridges have been equipped with sophisticated SHM systems in the mainland of China and in Hong Kong of China. Recently, SHM technology has been extended to field test systems. In this view, SHM can serve as a tool to develop the methods of life-cycle performance design, evaluation, maintenance and management of bridges; to develop new structural analysis methods through validation and feedback from SHM results; and to understand the behavior of bridges under natural and man-made disasters, rapidly assess the damage and loss of structures over large regions after disasters, e.g., earthquake, typhoon, flood, etc. It is hoped that combining analytical methods, numerical simulation, small-scale tests and accelerated durability tests with SHM could become the main engine driving the development of bridge engineering. This paper demonstrates the above viewpoint.

• Maxillofacial Plastic and Reconstructive Surgery
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• v.39
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• pp.6.1-6.6
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• 2017

Background: The purpose of this study is to evaluate the outcomes of four patients receiving stock Biomet TMJ prosthesis for reconstruction of the TMJs. Methods: TMJ reconstruction with stock Biomet TMJ prosthesis was performed in four patients who had joint damages by trauma, tumor, resorption, and ankylosis, which represent the indications of alloplastic prosthesis. Results: Loss of condyle from trauma and resorption of joint are good indications for prosthesis, but the patients should be informed about limitation of jaw movement. In case of structural damage of TMJ by tumor, tumor recurrence should be considered before planning TMJ reconstruction. Considering heterotopic bone formation in case of ankylosis, periodic follow-up and special surgical technique are required. Conclusions: Given careful treatment planning and understanding the functional limitation of TMJ prosthesis, alloplastic prosthesis is a safe and effective management option for the reconstruction of TMJs.

• Tribology and Lubricants
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• v.35 no.5
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• pp.317-322
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• 2019

In spite of progress in tribological research, machine component failure due to friction and wear has been reported frequently. This failure may lead to secondary damage that can cause huge expense for maintenance and repair. To prevent economic loss, it is important to detect and predict the initial failure point. In this sense, various researchers have been tried to develop Condition Monitoring (CM) method using Acoustic Emission (AE) generated while the materials undergo failure. In this study, effect of particles on friction and wear was investigated using the pin-on-plate friction test and AE signal was recorded with a band-width type AE sensor. The experiments were performed in dry and lubricant conditions using steel and glass as specimens. After the experiment, 3D laser microscope image was captured to evaluate the wear behavior quantitatively. The AE signal was analyzed in time-domain and frequency-domain. The amplitude was compared with the frictional results. The results of this study showed that particle generation accelerate wear, generate high magnitude AE signal and change the frequency characteristics of the signal. Also, lubricant condition test results showed low coefficient of friction, low wear rate, and low magnitude of AE signal compared to the dry condition. It is expected that the results of this study will aid in better assessment of wear in CM technology

• Geomechanics and Engineering
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• v.17 no.1
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• pp.109-118
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• 2019

The movement of soil along a slope during rainfall can cause serious economic damage and can jeopardize human life. Accordingly, predicting slope stability during rainfall is a major issue in geotechnical engineering. Due to rainwater penetrating the soil, the negative pore water pressure will decrease, in turn causing a loss of shear strength in the soil and ultimately slope failure. More seriously, many constructions such as houses and transmission towers built in/on slopes are at risk when the slopes fail. In this study, the numerical simulation using 2D finite difference program, which can solve a fully coupled hydromechanical problems, was used to evaluate the effects of soil properties, rainfall conditions, and the location of a foundation on the slope instability and slope failure mechanisms during rainfall. A slope with a transmission tower located in Namyangju, South Korea was analyzed in this study. The results showed that the correlation between permeability and rainfall intensity had an important role in changing the pore water pressure via controlling the infiltrated rainwater. The foundation of the transmission tower was stable during rainfall because the slope failure was estimated to occur at the toe of the slope, and did not go through the foundation.

• The Journal of the Society of Stroke on Korean Medicine
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• v.13 no.1
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• pp.77-85
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• 2012

Amyotrophic lateral sclerosis(ALS) is a progressive disorder that causes degeneration of motor neurons of the brain and spinal cord. It is characterized by loss of motor neurons leading to muscle weakness, and sensation and mental function stay intact during the course of the disease. Diagnostic tests include magnetic response imaging(MRI), electromyogram(EMG), muscle biopsy, and blood tests. In order to a definitive diagnosis of ALS, damage must be evident in both upper and lower motor neurons. When three limbs are sufficiently affected, the diagnosis is ALS. There is no cure for ALS. We experienced one case of ALS, the patients was diagnosed as ALS by EMG and symptoms. We diagnosed her as ShinEumHur(SEH) and treated by Choakwiyeum(左歸飮). We report the change of her symptoms through oriental medical treatment.

• Journal of Information Technology Applications and Management
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• v.30 no.6
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• pp.69-80
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• 2023

Ship collision accidents not only cause loss of life and property damage, but also cause marine pollution and can become national disasters, so prevention is very important. Most of these ship collision accidents are caused by human factors due to the navigation officer's lack of vigilance and carelessness, and in many cases, they can be prevented through the support of a system that helps with situation awareness. Recently, artificial intelligence has been used to develop systems that help navigators recognize the situation, but the sea is very wide and deep, so it is difficult to secure maritime traffic datasets, which also makes it difficult to develop artificial intelligence models. In this paper, to solve these difficulties, we propose a method to build a dataset with characteristics similar to actual maritime traffic datasets. The proposed method uses segmentation and inpainting technologies to build a foreground and background dataset, and then applies compositing technology to create a synthetic dataset. Through prototype implementation and result analysis of the proposed method, it was confirmed that the proposed method is effective in overcoming the difficulties of dataset construction and complementing various scenes similar to reality.

• Transactions on Electrical and Electronic Materials
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• v.17 no.6
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• pp.359-362
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• 2016

In the PV (Photovoltaic) power system, a junction box collects the DC voltage generated from the PV module and transfers it to the PCS (power conditioning system). The junction box prevents damage caused by the voltage difference between the serially connected PV modules and provides convenience while repairing or inspecting the PV array. In addition, the junction box uses the diode to protect modules from the inverse current when the PV power system and electric power system are connected for use. However, by using the reverse blocking diode, heat is generated within the junction box while generating electric power, which decreases the generating efficiency, and causes short circuit and electric leakage. In this research, based on the purpose of improving the performance of the PV module by decreasing the heat generation within the junction box, a junction box with a built-in bypass circuit was designed/manufactured so that a certain capacity of current generated from the PV module does not run through the reverse blocking diode. The manufactured junction box was used to compare the electric power and heating power generated when the circuit was in the bypass/non-bypass modes. It was confirmed that the electric power loss and heat generation indicated a decrease when the circuit was in the bypass mode.

• Molecules and Cells
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• v.40 no.4
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• pp.307-313
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• 2017

Caloric restriction (CR) has been shown to extend lifespan and prevent cellular senescence in various species ranging from yeast to humans. Many effects of CR may contribute to extend lifespan. Specifically, CR prevents oxidative damage from reactive oxygen species (ROS) by enhancing mitochondrial function. In this study, we characterized 33 single electron transport chain (ETC) gene-deletion strains to identify CR-induced chronological lifespan (CLS) extension mechanisms. Interestingly, defects in 17 of these 33 ETC gene-deleted strains showed loss of both respiratory function and CR-induced CLS extension. On the contrary, the other 16 respiration-capable mutants showed increased CLS upon CR along with increased mitochondrial membrane potential (MMP) and intracellular adenosine triphosphate (ATP) levels, with decreased mitochondrial superoxide generation. We measured the same parameters in the 17 non-respiratory mutants upon CR. CR simultaneously increased MMP and mitochondrial superoxide generation without altering intracellular ATP levels. In conclusion, respiration is essential for CLS extension by CR and is important for balancing MMP, ROS, and ATP levels.

• Journal of Dental Anesthesia and Pain Medicine
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• v.17 no.2
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• pp.149-155
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• 2017

Cerebral palsy is a non-progressive disorder resulting from central nervous system damage caused by multiple factors. Almost all cerebral palsy patients have a movement disorder that makes dental treatment difficult. Oral hygiene management is difficult and the risks for periodontitis, dental caries and loss of multiple teeth are high. Placement of dental implants for multiple missing teeth in cerebral palsy patients needs multiple rounds of general anesthesia, and the prognosis is poor despite the expense. Therefore, making the decision to perform multiple dental implant treatments on cerebral palsy patients is difficult. A 33-year-old female patient with cerebral palsy and mental retardation was scheduled for multiple implant treatments. She underwent computed tomography (CT) under sedation and the operation of nine dental implants under general anesthesia. Implant-supported fixed prosthesis treatment was completed. During follow-up, she had the anterior incisors extracted and underwent the surgery of 3 additional dental implants, completing the prosthetic treatment. Although oral parafunctions existed due to cerebral palsy, no implant failure was observed 9 years after the first implant surgery.

• Journal of Chest Surgery
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• v.24 no.11
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• pp.1068-1073
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• 1991

Bleeding after open heart surgery with cardiopulmonary bypass was a cause of concern. requiring reexploration of the chest in approximately 8 percent of patients who have had operations on the heart. From April., 1983 to October, 1991, 16 patients[2%] out of 777 patients who underwent open cardiac surgery had emergency reexploration with bleeding at the Department of Thoracic and Cardiovascular Surgery, Chungnam National University Hospital. In 12 cases[75%], reexploration was performed for continuous bleeding and the reminder[4 cases] were performed for suspected tamponade & hypotension. There were 9 cases[56%] of congenital heart disease and 7 cases of acquired heart disease. The mean blood loss were 997$\pm$472ml /sq. M in total cases and 1442$\pm$ 647ml /sq. M in cases repair of cyanotic heart disease. The mean interval till reoperation was 16.6hr [1hr~72hr] and 41 hr[12~72hr] in tamponade cases and 8.4hr[1hr~24hr] in continuous bleeding cases. The bleeding sites were identified in 7 cases: aortotomy site in 2 cases, ventriculotomy site, SVC, thymus, pleura and sternum wiring site in each other case. But no specific sites was found in the remaining 9 cases. The 8 cases had complications but all except 1 cases with hypoxic brain damage were recovered without sequale. We conclude that emergency thoractomy after open heart surgery may be lifesaving and-/or diminishing complications with bleeding if performed promptly with excessive bleeding, tamponade and unexpected hypotension.