• Journal of IKEEE
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• v.26 no.3
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• pp.380-388
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• 2022

The traditional malware detection technologies collect known malicious programs and analyze their characteristics. Then such a detection technology makes a blacklist based on the analyzed malicious characteristics and checks programs in the user's system based on the blacklist to determine whether each program is malware. However, such an approach can detect known malicious programs, but responding to unknown or variant malware is challenging. In addition, since such detection technologies generally monitor all programs in the system in real-time, there is a disadvantage that they can degrade the system performance. In order to solve such problems, various methods have been proposed to analyze major behaviors of malicious programs and to respond to them. The main characteristic of ransomware is to access and encrypt the user's file. So, a new approach is to produce the whitelist of programs installed in the user's system and allow the only programs listed on the whitelist to access the user's files. However, although it applies such an approach, attackers can still perform malicious behavior by performing a DLL(Dynamic-Link Library) injection attack on a regular program registered on the whitelist. This paper proposes a method to respond effectively to attacks using DLL injection.

• Journal of the Korea Institute of Information Security & Cryptology
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• v.24 no.1
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• pp.107-122
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• 2014

The DDoS attacks and the APT attacks occurred by the zombie computers simultaneously attack target systems at a fixed time, caused social confusion. These attacks require many zombie computers running attacker's commands, and unknown malware that can bypass detecion of the anti-virus products is being executed in those computers. A that time, many methods have been proposed for the detection of unknown malware against the anti-virus products that are detected using the signature. This paper proposes a method of unknown malware detection using digital forensic techniques and describes the results of experiments carried out on various samples of malware and normal files.

• Clinical and Experimental Pediatrics
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• v.56 no.12
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• pp.545-549
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• 2013

We report the case of a 17-year-old Korean girl with systemic lupus erythematosus (SLE) who presented with sudden weakness of the right-sided extremities and dysarthria. Oral prednisolone was being taken to control SLE. Results of clinical and laboratory examinations did not show any evidence of antiphospholipid syndrome or thromboembolic disease nor SLE activity. Cerebral angiography showed stenosis of the left internal carotid artery and right anterior cerebral artery with accompanying collateral circulation (moyamoya vessels). After the patient underwent bypass surgery on the left side, she recovered from the neurological problems and did not experience any additional ischemic attack during the 14-month follow-up period. This case represents an unusual association between moyamoya syndrome and inactive SLE (inactive for a relatively long interval of 2 years) in a young girl.

• Journal of Chest Surgery
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• v.21 no.6
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• pp.996-1002
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• 1988

A clinical analysis was performed on 115 cases of -patent ductus arteriosus treated surgically during the period of 11 years from Aug. 1977 to Jul. 1988. at the Department of Thoracic and Cardiovascular Surgery, Chungnam National University Hospital. Among 115 cases, male was 38 and female was 77 and ages ranged 12 days to 27 years old with the average of 8 7/12 years. The major clinical symptoms on admission were frequent URI attack[77.4%], dyspnea on exertion[32.2%] and palpitation[13%]. On auscultation, continuous machinery murmurs were detected in 97 cases[84.3%] and loud systolic murmurs were detected in 18 cases[15.7%]. Preoperative electrocardiographic findings were as follows: LVH 59[51.3%], RVH 12[10.4%], BVH 16[13.9%] and WNL 28[24.3%]. Radiologically, there were increased pulmonary vascularity in 104[90.4%] and cardiomegaly 62[53.9%]. Cardiac catheterization were performed in 101 cases and mean systolic pulmonary arterial pressure was 49.84*29.7mmHg and mean Qp/Qs was 2.95k1.8. Methods of operation were multiple ligation in 96, division in 11 and transpulmonary arterial repair using cardiopulmonary bypass in 8. Complication were recannalization in 2, temporary hoarseness due to left recurrent laryngeal nerve paralysis in 3 and respiratory distress in 1 and overall mortality rate was 1.7%[2 cases].

• Journal of Korean Neurosurgical Society
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• v.62 no.2
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• pp.136-143
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• 2019

Moyamoya disease (MMD) is a progressive cerebrovascular disease with unknown etiology, characterized by bilateral steno-occlusive changes at the terminal portion of the internal carotid artery and an abnormal vascular network formation at the base of the brain. MMD has an intrinsic nature to convert the vascular supply for the brain from internal carotid (IC) system to the external carotid (EC) system, as indicated by Suzuki's angiographic staging. Insufficiency of this 'IC-EC conversion system' could result not only in cerebral ischemia, but also in intracranial hemorrhage from inadequate collateral anastomosis, both of which represent the clinical manifestation of MMD. Surgical revascularization prevents cerebral ischemic attack by improving cerebral blood flow, and recent evidence further suggests that extracranial-intracranial bypass could powerfully reduce the risk of re-bleeding in MMD patients with posterior hemorrhage, who were known to have extremely high re-bleeding risk. Although the exact mechanism underlying the hemorrhagic presentation in MMD is undetermined, most recent angiographic analysis revealed the characteristic angio-architecture related to high re-bleeding risk, such as the extension and dilatation of choroidal collaterals and posterior cerebral artery involvement. We sought to update the current management strategy for hemorrhagic MMD, including the outcome of surgical revascularization for hemorrhagic MMD in our institute. Further investigations will clarify the optimal surgical strategy to prevent hemorrhagic manifestation in patients with MMD.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2014.05a
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• pp.257-260
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• 2014

Digital Forensics in the event of an accident, the system restore files and the only way to find evidence KT Website hacking happening now, credit card companies, and leakage of personal information by three recent spills occurred, such as Skin Food Home Up Customer Information hackers to find these crimes only means as well. This study attempted to bypass the KT website hacking attacks utilizing automated programs hacking programs, and if you try to experiment on whether any information has been disclosed and if so what home attacked forensics evidence for hackers to locate the can make a report is described.

• Journal of Chest Surgery
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• v.36 no.3
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• pp.142-149
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• 2003

To know the feasibility of the coronary artery bypass graft (CABG) for multivessel coronary artery disease with purely bilateral internal thoracic arteries (ITAs), we analyzed the short-term clinical results and the coronary angiography of the patients. Material and Method: From March 2001 to June 2002, four hundred and five patients underwent CABG. Purely bilateral ITAs were used in 159 patients (39.3%). We analyzed these patients retrospectively The mean age of these patients was $61.2{\pm}8.5$ (range: 30 ~80) years and there were 123 male patients. The preoperative risk factors were as follows: diabetes in 54 patients (34.0%), history of acute myocardiac infarction within 4 weeks in 29 (18.2%), and emergency operation in 6 (3.8%). Off-pump CABG was carried out in 128 patients (80.5%). Associated procedures were mitral valvuloplasty (5), aortic valve replacement (3), Dor procedure (1), and so on. Result: The mean number of distal anastomoses was $3.1{\pm}0.9$ (range: 2~6), the mean duration of hospital stay was $8.4{\pm}4.5$ days. There was one (0.6%) operative death. Except for one early death, no other patients suffered from low cardiac output. The other postoperative complications were occurred as follows: reoperation due to bleeding in 3 patients, perioperative myocardiac infarction in 1, transient cardiac arrest in 2, transient cognitive dysfunction in 7, and transient ischemic attack in 1, and deep sternal wound infection in 1 patient. Recently, early postoperative angiography was performed in 19 patients who had triple vessel disease. The total number of distal anastomosis was 78 (mean $4.1{\pm}0.8$/patient). All distal anastomosis sites were patent, but competition flow was observed at the bypass sites where the native coronary artery stenosis was not significant. Conclusion: The CABG with purely bilateral ITAs for triple vessel disease was performed safely. The early patency rate was relatively good in small number of patients. However the long-term patency rate and the functional study to evaluate the sites where competition flow was observed should be followed.

• Journal of Chest Surgery
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• v.32 no.9
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• pp.790-798
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• 1999

Background: As the early outcome after coronary artery bypass grafting(CABG) has been stabilized, neurologic complication has now become one of the most important morbidity. The aim of this study was to find out the risk factors associated with the neurologic complications after CABG. Material and Method: In 351 patients who underwent CABG, the incidence and features of neurologic complications, with associated perioperative risk factors, were retrospectively reviewed. Neurologic complication was defined as a new cerebral infarction confirmed by postoperative neurologic examination and radiologic studies, or delayed recovery of consciousness and orientation for more than 24 hours after the operation. Result: Neurologic complications occurred in 18 patients(5.1%), of these nine(2.6%) were diagnosed as having new cerebral infarctions(stroke). Stroke was manifested as motor paralysis in four patients, mental retardation or orientation abnormality in four, and brain death in one. Statistical analysis revealed the following variables as significant risk factors for neurologic complications by both univariate and multivariate analyses: cardiopulmonary bypass longer than 180 minutes, atheroma of the ascending aorta, carotid artery stenosis detected by Duplex sonography, and past history of cerebrovascular accident or transient ischemic attack. Age over 65 years, aortic calcification detected by simple X-ray, and intraoperative myocardial infarction were significant risk factors by univariate analysis only. Neither the severity of carotid artery stenosis nor technical modifications such as cannulation of the aortic arch or single clamp technique, which were expected to affect the inciden e of neurologic complications, had significant relationship with the incidence. Conclusion: This study confirmed the strong association between neurologic complications after CABG and atherosclerosis of the arterial system. Therefore, to minimize the incidence of neurologic complications, systematic evaluation focused on atherosclerotic lesions of the arterial system followed by adequate alteration of operative strategy is needed.

• Journal of Internet Computing and Services
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• v.21 no.1
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• pp.179-190
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• 2020

In the Unix-like system environment, the GOT overwrite attack is one of the traditional control flow hijacking techniques for exploiting software privileges. Several techniques have been proposed to defend against the GOT overwrite attack, and among them, the Full Relro(Relocation Read only) technique, which blocks GOT overwrites at runtime by arranging the GOT section as read-only in the program startup, has been known as the most effective defense technique. However, it entails loading delay, which limits its application to a program sensitive to startup performance, and it is not currently applied to the library due to problems including a chain loading delay problem caused by nested library dependency. Also, many compilers, including LLVM, do not apply the Full Relro technique by default, so runtime programs are still vulnerable to GOT attacks. In this paper, we propose a GOT protection scheme using the Control Flow Integrity(CFI) technique, which is currently recognized as the most suitable technique for defense against code reuse attacks. We implemented this scheme based on LLVM and applied it to the binutils-gdb program group to evaluate security, performance and compatibility. The GOT protection scheme with CFI is difficult to bypass, fast, and compatible with existing library programs.

• Journal of Korean Academy of Fundamentals of Nursing
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• v.16 no.4
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• pp.497-505
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• 2009

Purpose: The purpose of this study was to identify the level of quality of life and gender differences in predictors of quality of life among patients with coronary artery disease. Methods: Participants for this descriptive survey were 67 men and 65 women who signed informed consents. They were patients who had undergone coronary artery bypass graft surgery or percutaneous transluminal coronary angioplasty, or were on medication therapy after a heart attack. The Short-Form Health Survey (SF-36), Personal Resource Questionnaire-part (II), and the Center for Epidemiologic Studies Depression Scale were used to measure quality of life, social support, and depression respectively. Gender and age were controlled because they were reported as influencing factors in previous studies. Results: There were significant differences in depression and quality of life between men and women however, social support was not significantly different by gender. In multiple regression analysis, depression was a significant predictor and explained 51.9% of quality of life for men. In women, depression and social support were significant predictors and explained 50.9% of quality of life. Conclusion: Factors influencing quality of life for men and women were different, and therefore, nurses need to consider their patients' gender and use specific strategies to improve quality of life for patients with coronary artery disease.