• Journal of the Korean Society for Railway
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• v.11 no.2
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• pp.139-144
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• 2008

Recent advances in embedded system technology have brought more dependence on automating train control. While much efforts have been reported to improve electronic hardware's safety, not so much systematic approaches to evaluate software's safety, especially for the vital software running on board train controllers. In this paper, we propose a new software tool to evaluate software safety for the train controller. We have reviewed requirements in the international standards and surveyed available tools in the market. From that, we identified necessary tests to meet the standards and proposed a tool that can be used during the whole software life cycle. We show the functional architecture and internal components of the tool. Our tool is unique in that it is a comprehensive tool specifically designed for software safety evaluation while other tools are not.

• Journal of the Korean Society for Railway
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• v.13 no.4
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• pp.396-403
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• 2010

Train control system require high level of safety since these are vital control system to ensure safe operation of the train. According to these reason, safety-related regulations for railway signaling systems are standardized in IEC. In Korea, many attempts are tried to procure the level to meet the international standards, but thats's efforts are beginning steps. HAZOP study is recommended for hazard analysis at IEC standards, but this method has several unsuitable problems because this method is developed in chemical plant domain. In this paper we recommend new method of HAZOP, named HAZOP-KR, which would be suitable for analyzing safety of the train control systems. An example of this method applied to real system is also included.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.16 no.9
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• pp.5802-5809
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• 2015

Railway signaling system is the vital control system in charge of the core for safely train operation, its functional safety must be checked through sufficient verification. Until now, to verify the interoperability of developed railway signaling system, the on-site testing approaches have been applied after testing in laboratory with simulator. This approaches are some limited range of interoperable verification, so more systematic verification interoperability is required. In this paper, the three phases of interoperability verification for railway signaling system was proposed, and methodology for each phases are represented. And also The interoperability validation methodology and supported testing tool for railway signaling system is represented in this paper

• KIPS Transactions on Computer and Communication Systems
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• v.9 no.12
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• pp.315-320
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• 2020

Identity authentication is an important technology that has long been used in society to identify individuals and provide appropriate services. With the development of the Internet infrastructure, many areas have expanded into online areas, and identity authentication technologies have also expanded online. However, there is still a limit to identity authentication technology that relies entirely on trusted third parties like the government. A centralized identity management system makes the identification process between agencies with different identity management systems very complex, resulting in a waste of money and time for users. In particular, the limits of the centralized identity management system were clearly revealed in the face mask shortage in the 2020 COVID-19 crisis. A Decentralized Identity (DID) is a way for users to manage their identity on their own, and recently, a number of DID platform based on blockchain technology have been proposed. In this paper, we analyze the limitations of the existing centralized identity management system and propose a DID system that can be utilized in future national emergency situations such as COVID-19.

• Journal of Chest Surgery
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• v.42 no.4
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• pp.520-523
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• 2009

Aortic arch aneurysm generally requires an urgent treatment due to the risk of catastrophic aortic rupture. However conventional surgery for aortic arch repair still carries significant risks of postoperative morbidity and mortality, especially in patients with old age. In an effort to correct the aortic pathology while minimizing the risks of complication, we performed a hybrid technique which comprises the off pump arch aortic stent grafting in an 86-old male patient with an aortic arch aneurysm.

• Tuberculosis and Respiratory Diseases
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• v.55 no.3
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• pp.297-302
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• 2003

Background : Airway obstruction due to blood clot occurs unusually but in a variety of clinical settings. Initial efforts for removal of the endobronchial blood clot involve flexible bronchoscopic evaluation with saline lavage and suctioning and then forceps extraction. If unsuccessful, further options include rigid bronchoscopy, Fogarty catheter dislogement of the clot, and topical thrombolytic agents. The several successful uses of endobronchial streptokinase or urokinase to dissolve an endobronchial blood clot have been previously reported, but not yet in Korea. Herein we describe a 51-year old man with superior vena cava thrombosis secondary to Behcet's disease who experienced life threatening airway obstruction after hemoptysis due to a large organized blood clot in left main bronchus. Urokinase(260,000 U), injected through a fiberoptic bronchoscope, totally dissolved the clot. No complications occurred.

• Tuberculosis and Respiratory Diseases
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• v.65 no.4
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• pp.313-317
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• 2008

Lipoma is a common neoplasm in soft tissues. However, an intrapulmonary lipoma is a rare benign tumor. Patients with a bronchial lipoma might have a malignant potential related to their smoking history due to the case reports of lung cancer accompanied with lipoma. Endobronchial lipoma can cause irreversible parenchymal lung damage if not diagnosed and treated early. Therefore, it should initially be treated by fiberoptic bronchoscopy or surgery depending on the status of distal parenchymal lung damage. Bronchiolitis obliterans with organizing pneumonia (BOOP) is a pathological syndrome that is defined by the presence of buds of granulation tissue consisting of fibroblasts and collagen within the lumen of the distal air spaces. BOOP is caused by drug intoxication, connective tissue disease, infection, obstructive pneumonia, tumors, or an unknown etiology. We encountered a 58 year-old male patient with endobronchial lipoma, causing the collapse of the right middle and lower lobes, and BOOP due to obstructive pneumonia.

• KSBB Journal
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• v.17 no.1
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• pp.100-105
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• 2002

N-acetyl-D-glucosamine oligosaccharides [(GlcNAc)n] whose degree of polymer-ization is from one to ten (n=1-10) were fractionated by column chromatography on CM-Sephadex. Electro dialysis from a partially deacetylated chitosan hydrolysate prepared crudely with the N-acetyl-D-glucosaminidase(chitinase) and exo-N, N'-diacetylchito-biohydrolase(chitobiase) of Serratia marcescens QM B1466. Reducing sugar compositions and sequences of the N-acetyl-glucosamine oligosaccharides were identified by N-acetylation, randomly cleavage with chitinase and ego-splitting with chitobiase. N-acetyl-glucosamine heterochitooligosaccharides with glucosamine oligosaccharides, (GlcN)n at the reducing end residues together with $(GlcN)_1\sim(GlcN)_4$ were detected. Separation was accomplished by prefractionation with election by 0 to 1.0 M NaCl gradient solution. $(GlcNAc)_1 =4.25%,\; (GlcNAc)_2=4.49%,; (GlcNAc)_3=11.1%,\; (GlcNAc)_4=2.5%,$$ $(GlcNAc)_{5}$=0.64%, $(GlcNAc)_{6}$=2.12% and $(GlcNAc)_{7}$=1.21%, respectively, were crystallized after electrodialysis and lyophilization Each N-acetyl-D-glucosamine oligosaccharides content were detected by HPLC.

• Korean Journal of Weed Science
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• v.30 no.4
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• pp.340-360
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• 2010

The depletion of fossil fuels, ecological problems associated with $CO_2$ emissions climate change, growing world population, and future energy supplies are forcing the development of alternative resources for energy (heat and electricity), transport fuels and chemicals: the replacement of fossil resources with $CO_2$ neutral biomass. Several options exist to cover energy supplies of the future, including solar, wind, and water power; however, chemical carbon source can get from biomass only. When used in combination with environmental friend production and processing technology, the use of biomass can be seen as a sustainable alternative to conventional chemical feedstocks. The biorefinery concept is analogous to today's petroleum refinery, which produce multiple fuels and chemical products from petroleum. A biorefinery is a facility that integrates biomass conversion processes and equipment to produce fuels, power, and value-added chemicals from biomass. Biorefinery is the co-production of a spectrum of bio-based products (food, feed, materials, and chemicals) and energy (fuels, power, and heat) from biomass [definition IEA Bioenergy Task 42]. By producing multiple products, a biorefinery takes advantage of the various components in biomass and their intermediates therefore maximizing the value derived from the biomass feedstocks. A biorefinery could, for example, produce one or several low-volume, but high-value, chemical or nutraceutical products and a low-value, but high-volume liquid transportation fuel such as biodiesel or bioethanol. Future biorefinery may play a major role in producing chemicals and materials as a bridge between agriculture and chemistry that are traditionally produced from petroleum. Industrial biotechnology is expected to significantly complement or replace the current petroleum-based industry and to play an important role.

• Tuberculosis and Respiratory Diseases
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• v.61 no.2
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• pp.157-161
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• 2006

A 70-year-old man was referred to the department of pulmonology due to blood tinged sputum and an abnormal chest X-ray. The chest X-ray and CT scans revealed a lobulated contour mass-like lesion in the left upper lung field. The bronchoscopic examination showed a whitish and polypoid mass occluding the left upper lobe bronchus. A biopsy specimen from the lesion revealed many aspergillus hyphae. Intravenous and oral itraconozole were administered over a 4 weeks period. Several months later, the size of the mass on chest X-ray increased and a percutaneous lung biopsy revealed a sarcomatoid carcinoma. We reported a case of lung cancer that was obscured by an endobronchial aspergilloma with a review of the relevant literature.