• Journal of Digital Convergence
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• v.12 no.1
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• pp.313-317
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• 2014

Smart-phone, PC or tablet platforms, such as smart terminals spread to the masses trying to capitalize. Smart TV also is increasing. In Korea, market size of TV is growing fast with growth of risk of hacking. In this paper, several kinds of Smart TV hacking cases are presented with the possibility of attacks against the vulnerability analysis and countermeasures. Most of the Linux operating system is open. Thus, it is vulnerable for latest hacking techniques. Most are based on the Linux OS to enhance security mount Sand-Box. However, bypass procedure using the technique, or APT attacks can avoid San-Box technique. New hacking techniques and a variety of ways will occur in the future. Therefore, this paper will develop Smart TV, and it analysis of a security threat and establishes better prepared in the future because new hacking attacks are expected to prepare more.

• Journal of Korean Society of Transportation
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• v.27 no.3
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• pp.91-102
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• 2009

A traffic accident prediction model developed using various design variables(road design variables, geometric variables, and traffic environmental variables) is one of the most important factors to safety design evaluation system for roads. However, statistical accident models have a crucial problem not applicable for all intersections. To make up this problem, this study developed AMFs(Accident Modification Factors) through statistical modeling methods, historical accident databases, judgment from traffic experts, and literature review by considering design variable's characteristics, traffic accident rates, and traffic accident frequency. AMFs developed in this study include exclusive left-turn lane, exclusive right-turn lane, sight distance, and intersection angle. Predictabilities of the developed AMFs and the existing accident prediction models are compared with real accident historical data. The results showed that performances of the developed AMFs are superior to the existing statistical accident prediction models. These findings show that AMFs should be considered as a important process to develop safety design evaluation algorithms. Additionally, AMFs could be used as an index that can judge the impact of corresponding design variables on accidents in rural intersections.

• Journal of Chest Surgery
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• v.38 no.3 s.248
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• pp.241-244
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• 2005

A 57-year-old man with numbness and paresthesia of left arm is presented. There was no pulse in the left arm was absent and his chest radiograph suggested right-sided aortic arch. The aortogram showed right-sided aortic arch with Kommerell's diverticulum. The proximal portion of left subclavian artery was totally occluded and blood was being supplied through vertebral arteries to distal subclavian artery. He underwent bypass grafting between both subclavian arteries by an expanded polytetrafluoroethylene graft. Because the size of Kommerell's diverticulum was small, it need to be observed closely.

• Journal of Yeungnam Medical Science
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• v.28 no.2
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• pp.124-132
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• 2011

Background: Antiplatelet agent administration is critical in managing coronary-artery disease, but there is a concern regarding operation-related bleeding and an increase in blood transfusion in such, especially when delivering combined antiplatelet agents. This study was conducted to evaluate the effect of the administration of antiplatelet agents on off-pump coronary-artery bypass surgery (OPCAB). Methods: From March 2003 to December 2009, 49 patients who had undergone OPCAB were collected retrospectively. The patients were divided into three groups according to the administration of antiplatelet agents before the OPCAB operation: 21 patients were given an aspirin agent (group 1), 19 patients were given combined agents (aspirin+clopidogrel) (group 2), and nine patients were not given any antiplatelet agent (group 3). The three groups' perioperative hematologic and coagulation profiles, including their platelet counts, hemoglobin levels, hematocrit, prothrombin times, and aPTTs (activated partial thromboplastin times), and their postoperative bleeding, related complications, transfusion requirements, and operation times, were compared. Results: The operation time in group 2 was 4.3 hours, longer than those in the two other groups, and urgent operation was significantly most frequent in group 2 (63%). The amount of blood loss and the number of patients who received blood transfusion were not different in the three groups. The perioperative hemoglobin level, hematocrit, platelet count, prothrombin time, and aPTT were also not significantly different among the three groups. Conclusion: The continuous administration of antiplatelet agents to the patients in this study did not increase their postoperative bleeding or operation-related complications. Therefore, OPCAB may well be considered even if combined antiplatelet agents are being administered.

• The KIPS Transactions:PartC
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• v.16C no.5
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• pp.543-554
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• 2009

The openness of the Web allows any user to access any type of information easily at any time and anywhere. However, with function of easy access for useful information, internet has dysfunctions of providing users with harmful contents indiscriminately. Some information, such as adult content, is not appropriate for children. To protect children from these harmful contents, many filtering softwares are developed. However, these softwares can not prevent harmful contents, perfectly, because of some limitations. In this paper, we analyze existing eleven filtering softwares and state the limitation of these softwares. Furthermore, we propose requirements for new filtering software which overcomes the limitations, and describe framework of the new software.

• Journal of Convergence Society for SMB
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• v.2 no.2
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• pp.35-41
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• 2012

The rapid development of cloud computing and mobile internet service changes to an mobile cloud service environment that can serve and pay computing source that users want anywhere and anytime. But when user misses mobile device, the respond to any threat like user's personal information exposal is insufficient. This paper proposes cloud service access control model to provide secure service for mobile cloud users to other level users. The proposed role-based model performs access authority when performs user certification to adapt various access security policy. Also, the proposed model uses user's attribute information and processes before user certification therefore it lowers communication overhead and service delay. As a result, packet certification delay time is increased 3.7% and throughput of certification server is increased 10.5%.

• Journal of Chest Surgery
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• v.26 no.2
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• pp.141-147
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• 1993

A total of 40 patients having a diagnosis of atherosclerotic coronary arterial disease were analysed on the operative outcomes according to variables as follows: 1) preoperative risk factors such as age, sex, CCS (Canadian Cardiovascular Society) functional class, type of angina, number of diseased vessel, presence of left main coronary artery stenosis, previous history of habitual smoking and presence of other medical diseases (diabetes mellitus, essential hypertension), 2) preoperative management such as intravenous infusion of nitroglycerine, preoperative IABP (intra-aortic balloon pump) support and whether the operation was scheduled as emergency or not, 3) intraoperative variables such as infusion method and composition of cardioplegic solutions, number of distal anastomosis, use of internal mammary artery, total cardiopulmonary bypass time and total cross clamp time. Complications included operative death in 12.5％, perioperative myocardial infarction in 25.0％ and perioperative arrhythmia in 17.5％. Nineteen perioperative variables were analyzed to identify risk factors for these end points. For operative death, presence of left main coronary artery stenosis (p = 0.056) and cardiopulmonary bypass time (p = 0.029) were significant in the univariate analysis, but presence of left main coronary artery lesion (p = 0.011, $\chi$$^2$= 6.45) and abscence of preoperative of IABP support (p = 0.069, $\chi$$^2$ = 3.30) were independent predictor in multivariate analysis (stepwise linear logistic regression).

• The KIPS Transactions:PartC
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• v.14C no.1 s.111
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• pp.45-54
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• 2007

As one of the most threatening attacks, DDoS attack makes distributed multiple agents consume some critical resources at the target within the short time, thus the extent and scope of damage is serious. Against the problems, the existing defenses focus on detection, traceback (identification), and filtering. Especially, in the hierarchical networks, the traffic congestion of a specific node could incur the normal traffic congestion of overall lower nodes, and also block the control traffic for notifying the attack detection and identifying the attack agents. In this paper, we introduce a DDoS attack tolerant network structure using a hierarchical overlay for hierarchical networks, which can convey the control traffic for defense such as the notification for attack detection and identification, and detour the normal traffic before getting rid of attack agents. Lastly, we analyze the overhead of overlay construction, the possibility of speedy detection notification, and the extent of normal traffic transmission in the attack case through simulation.

• Journal of Chest Surgery
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• v.39 no.2 s.259
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• pp.162-165
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• 2006

The innominate artery aneurysm is an uncommon entity. A 36-year-old man was transferred to our hospital because of incidental finding of right superior mediastinal mass. He had a history of blunt chest trauma due to automobile accident 16 years earlier. Computed tomography scanning demonstrated 5-cm sized sacular aneurysm with thrombus at the innominate artery. The prosthetic bifurcated bypass grafting from the ascending aorta to the right common carotid artery and right subclavian artery was performed under the moderate hypothermic cardioplumonary bypass. We report a successful surgical treatment for a rare case of the innominate artery aneurysm.

• Journal of Chest Surgery
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• v.41 no.2
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• pp.260-263
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• 2008

We performed three cases of extraanatomic bypass graft for treating adult coarctation. Two cases of left subclavian artery to descending aorta bypass graft were done via left thoracotomy for treating 2 patients who had extensive aortic occlusive disease. One case of ascending aorta to descending aorta bypass graft and aortic valve replacement was done via median sternotomy for a patient who had combined arch hypoplasia and aortic valve regurgitation. One patient was reoperated on for aneurysm rupture of an anastomosis site four months after the first operation and two patients have had no specific problems during and after their operations.