• Tuberculosis and Respiratory Diseases
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• v.78 no.4
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• pp.408-411
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• 2015

Pulmonary arteriovenous malformations (AVMs) are caused by abnormal vascular communications between the pulmonary arteries and pulmonary veins, which lead to the blood bypassing the normal pulmonary capillary beds. Pulmonary AVMs result in right-to-left shunts, resulting in hypoxemia, cyanosis, and dyspnea. Clinical signs and symptoms vary depending on the size, number, and flow of the AVMs. Transcatheter embolization is the treatment of choice for pulmonary AVMs. However, this method can fail if the AVM is large or has multiple complex feeding arteries. Surgical resection is necessary in those kind of cases. Here, we report the case of a patient with a 6-cm pulmonary AVM with multiple feeding arteries that was successfully treated by repeated coil embolization without surgery.

• The Transactions of The Korean Institute of Electrical Engineers
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• v.65 no.5
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• pp.878-882
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• 2016

These days, SFCLs are being developed in order to limit fault current. However, the superconducting elements that limit the fault current have such problems as capacity increase and require auxiliary devices including cooling device. If devices that comprise the current power network can withstand fault current for at least one cycle, it is possible to limit the fault current with current limiting elements by bypassing it on the fault line. In this study, the fault current limiter was configured with current transformer, vacuum interrupter, and current limiting element. Through the experience, it was confirmed that the fault current was limited within one cycle. The superconducting element, as a current limiting element, limited the fault current by 80 % within one cycle from fault occurrence, and the passive element limited it more than 95 %. Also, through the comparison between resistance curve and power consumption curve, it was confirmed that the current limiting element using a passive element was more stable than the superconducting element that required capacity increase and other auxiliary devices. It was considered that the FCL proposed in this study could limit fault current stably within one cycle from fault occurrence by using the existing power technologies such as fault current detection and solenoid valve operating circuit.

• Journal of Industrial Convergence
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• v.18 no.5
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• pp.36-41
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• 2020

This paper aims to explore and shed light on how the rise of streaming services has been affecting the media landscape in the recent years by looking at the conflicts between the Hollywood film industry and Netflix. It especially examines Netflix's disregard for the theatrical release, as it is the most portentous issue that could reshape the film industry, and Hollywood's opposition to it as revealed through the 2019 Academy Awards where the issue was brought into sharp relief. At the same time, this paper also questions whether theatrical distribution makes a film any more cinematic by examining how Hollywood film production has been largely concentrated on tentpoles and franchises, while Netflix has been producing diverse films often shunned by the studios. In this light, it concludes the changes wrought by Netflix, including its bypassing of the theatrical release, are not likely to be reversed.

• Journal of The Korea Institute of Healthcare Architecture
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• v.26 no.1
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• pp.7-15
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• 2020

Purpose: Emergency room(ER) is the first place to enter a hospital where patients who might have been infected with contagious disease. Therefore, ER should be designed with infection control in mind. Researchers examined hospital ER layouts to identify layout design that support infection control. Methods: This study analyzed the hospital ER layout of Korean and other hospitals abroad. Researchers focused on route of incoming patients who potentially have infectious disease. Crossing of this route with other routes such as for imaging and testing should be avoided for infection control. Results: There were certain hospital ERs with better control of infection related incidents. ER floor plan layout is analyzed about allocation of key functions with movement routes for each role such as patients and medical staff in mind. To identify layout strategies for ER functions researchers simplified the routes in ER into diagrams. Layout options show that bypassing infection suspected routes over other routes is possible. Implications: Hospitals can control infection easier when they adopt strategic ER layout identified in this study.

• Journal of the Korea Institute of Information Security & Cryptology
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• v.28 no.6
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• pp.1553-1561
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• 2018

The source code for Android is open and easy to modify depending on the purpose. Recently, this charateristic has been exploited to bypass the runtime protection technique and extract the original executable code. Unfortunately, Android devices are so fragmented that it is difficult to verify the integrity of the system. To solve this problem, this paper proposes a technique to verify the integrity of the execution environment indirectly using the features of the application permission. Before executing the original executable code, it loads and executes the dummy DEX file to monitor for abnormal events and determine whether the system is intact. The proposed technique shows a performance overhead of about 2 seconds and shows that it can detect the bypassing technique that is currently disclosed.

• Journal of the Korea Institute of Information Security & Cryptology
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• v.21 no.2
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• pp.49-60
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• 2011

Instant Messenger is one of the most popular communication service when translating message or data each other through Internet. For digital crime investigation, therefore, it is obviously important to obtain communication trace and contents derived from Instant Messenger. This is because that gathering traditional communication histories also have been important until now. However, extracting communication trace and contents are not easy because they are generally encrypted or obfuscated in local system, futhermore, sometimes they are located at server computer for Instant Messenger. This paper researches on extracting communication histories against NateOn, BuddyBuddy, Yahoo! messenger and Mi3 messenger, and obtaining user password or bypassing authentication system to Instant Messenger Service when a user use auto-login option.

• Nuclear Engineering and Technology
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• v.54 no.7
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• pp.2702-2713
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• 2022

A steam generator tube rupture accompanying a core damage may cause the fission product to be released to environment bypassing the containment. In such an accident, the steam generator is the major path of the radioactive aerosol release. AEOLUS facility, the scaled-down model of Korean type steam generator, was built to examine the aerosol removal in the steam generator during the steam generator tube rupture accident. Integral and separate effect tests were performed with the facility for the dry and flooded conditions, and the decontamination factors were presented for different tube configurations and submergences. The dry test results were compared with the existing test results and with the analyses to investigate the aerosol retention physics by the tube bundle, with respect to the particle size and the bundle geometry. In the flooded tests, the effect of submergence were shown and the retention in the jet injection region were presented with respect to the Stokes number. The test results are planned to be used to constitute the aerosol retention model, specifically applicable for the analysis of the steam generator tube rupture accident in Korean nuclear power plants to evaluate realistic fission product behavior.

• Korean Journal of Materials Research
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• v.32 no.8
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• pp.339-344
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• 2022

The lattice oxygen mechanism (LOM) is considered one of the promising approaches to overcome the sluggish oxygen evolution reaction (OER), bypassing -OOH^* coordination with a high energetic barrier. Activated lattice oxygen can participate in the OER as a reactant and enables O^*-O^* coupling for direct O₂ formation. However, such reaction kinetics inevitably include the generation of oxygen vacancies, which leads to structural degradation, and eventually shortens the lifetime of catalysts. Here, we demonstrate that Se incorporation significantly enhances OER performance and the stability of NiFe (oxy)hydroxide (NiFe) which follows the LOM pathway. In Se introduced NiFe (NiFeSe), Se forms not only metal-Se bonding but also Se-oxygen bonding by replacing oxygen sites and metal sites, respectively. As a result, transition metals show reduced valence states while oxygen shows less reduced valence states (O^-/O₂^2-) which is a clear evidence of lattice oxygen activation. By virtue of its electronic structure modulation, NiFeSe shows enhanced OER activity and long-term stability with robust active lattice oxygen compared to NiFe.

• Progress in Superconductivity and Cryogenics
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• v.11 no.3
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• pp.10-14
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• 2009

Since a stabilizer of YBCO coated conductor (CC) plays a very important role of bypassing over-current and transferring heat generated in the moment of fault, it is one of big issues to determine the material of the stabilizer and its dimension for the high performance of the HTS power application system. Especially, in the case of a superconducting fault current limiter (SFCL), which requires it to react immediately to the occurrence of fault, characteristics of stabilizer are decisive in limiting fault current and recovering superconducting properties during and after quenching. In this paper, the quench / recovery characteristics of YBCO CCs with various thickness of stabilizer were analyzed. The quench/recovery test carried out at 20 $V_{rms}$, 5 cycles (60 Hz) and results showed that as the thickness of the stabilizer decreased, both the final approach temperature and the recovery time decreased.

• Journal of Soil and Groundwater Environment
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• v.28 no.3
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• pp.1-11
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• 2023

Permeable reactive barrier (PRB) is a prominent in-situ remedial option for cleanup of contaminated groundwater and has been gaining increasing popularity in recent years. Funnel-and-gate systems, comprised of two side wings of impermeable walls and a central gate wall, are frequently implemented in many sites, but often suffers from bypassing of groundwater due to the progressive clogging of the gate wall over extended period of time. This study investigated technical feasibility of a hybrid funnel-and-gate system designed to address the flow deterioration in the gate wall. The key attribute of the proposed hybrid system is the operation of drainage units at the barrier walls and rear end of the gate wall. A conceptual modeling with MODFLOW indicated the groundwater inside the barrier was maintained at appropriate level to be guided toward the gate wall, yielding constant discharging of groundwater from the gate.