• 한국정보과학회논문지:정보통신
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• 제35권6호
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• pp.482-496
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• 2008

인터넷 라우터에서의 패킷 분류는 들어오는 모든 패킷에 대하여 패킷이 입력되는 속도와 같은 속도로 수행되어야 하는데, 여러 헤더 필드에 대해 다차원 검색을 수행하여야 하므로, 라우터 설계에 있어 가장 어려운 문제중의 하나이다. 계층적 패킷 분류 구조는 하나의 필드 검색이 끝날 때마다 검색 영역이 현저하게 줄어듦으로 매우 효율적이다. 그러나 계층적 구조들은 빈 노드와 역추적이라는 두가지 문제를 내재하고 있다. 본 논문에서는 두가지 문제를 동시에 해결하는 새로운 계층적 패킷분류 구조를 제안한다. 역추적 문제는 셋-프루닝 기법을 이용하여 해결하였으며, 이진 검색트리를 적용하여 빈노드를 제거하였다. 시뮬레이션 결과 제안된 알고리즘은 메모리 요구량의 증가 없이 검색 성능을 현저히 향상시킴을 확인하였다. 또한 셋-프루닝에 있어 제한된 룰의 복사를 적용하는 최적화 기법을 제안한다.

• JSTS:Journal of Semiconductor Technology and Science
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• 제3권3호
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• pp.132-138
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• 2003

We investigated the polarization retention characteristics of ferroelectric capacitors with $Pb(Zr,Ti)O_3$ (PZT) thin films which were fabricated by different deposition methods. In thermally-accelerated retention tests, PZT films which were prepared by a chemical solution deposition (CSD) method showed rapid decay of retained polarization charges as the thickness of the films decreased down to 100 nm, while the films which were grown by metal organic chemical vapor deposition (MOCVD) retained relatively large non-volatile charges at the corresponding thickness. We concluded that in the CSD-grown films, the thicker interfacial passive layer compared with the MOCVD-grown films had an unfavorable effect on retention behavior. We observed the existence of such interfacial layers by extrapolation of the total capacitance with thickness of the films and the capacitance of these layers was larger in MOCVD-grown films than in CSD-grown films. Due to incomplete compensation of surface polarization charges by the free charges in the metal electrodes, the interfacial field activated the space charges inside the interfacial layers and deposited them at the boundary between the ferroelectric layer and the interfacial layer. Such space charges built up an internal field inside the films, which interfered with domain wall motion, so that retention property at last became degraded. We observed less imprint which was a result of less internal field in MOCVD-grown films while large imprint was observed in CSD-grown films.

• The Journal of Korean Physical Therapy
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• 제27권4호
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• pp.252-257
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• 2015

Purpose: The purpose of this study was to assess psychometric properties of the Korean version of the Stroke Impact Scale 3.0 (K-SIS 3.0) in patients with stroke. Methods: Patients with stroke longer than 3 months were invited to participate in the study at specialized rehabilitation centers in Busan. Information on patients was collected using Mini-Mental State Examination (MMSE), Modified Bathel Index (MBI), Beck Depression Index (BDI), WHODAS 2.0-12 item, and K-SIS. Floor and ceiling effects of each domain of K-SIS were examined. The internal consistency of each domain of the K-SIS was calculated using Cronbach's ${\alpha}$. Correlation between K-SIS and each scale was assessed using Spearman's correlation coefficient. Results: Ninety subjects participated in the study. The K-SIS was found to have excellent internal consistency (Cronbach's ${\alpha}=0.93$). Each domain of the consistency ranged from 0.86 to 0.94, except the emotion (${\alpha}=0.51$). Significant correlations were observed between MMSE and domains of memory and thinking, and communication (r=0.48 and 0.52 respectively). BDI was negatively related to domains of emotion, ADL, mobility, and participation (r=-0.43, -0.49, -0.52 and -0.33 respectively). Specific daily activity (MBI) and general functioning (WHODAS 2.0) were also found to be closely related to the domains of ADL, mobility, and participation (ranging from r=-0.41 to r=-0.59). No ceiling and floor effect was observed. Conclusion: Excellent reliability and validity of K-SIS were obtained in the study and it could be suggested that K-SIS may be used for patients with stroke for collection of information on functioning in the clinical context.

• KSII Transactions on Internet and Information Systems (TIIS)
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• 제11권11호
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• pp.5642-5670
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• 2017

Antivirus is an important issue to the security of virtual machine (VM). According to where the antivirus system resides, the existing approaches can be categorized into three classes: internal approach, external approach and hybrid approach. However, for the internal approach, it is susceptible to attacks and may cause antivirus storm and rollback vulnerability problems. On the other hand, for the external approach, the antivirus systems built upon virtual machine introspection (VMI) technology cannot find and prohibit viruses promptly. Although the hybrid approach performs virus scanning out of the virtual machine, it is still vulnerable to attacks since it completely depends on the agent and hooks to deliver events in the guest operating system. To solve the aforementioned problems, based on in-memory signature scanning, we propose an agentless runtime antivirus system VirtAV, which scans each piece of binary codes to execute in guest VMs on the VMM side to detect and prevent viruses. As an external approach, VirtAV does not rely on any hooks or agents in the guest OS, and exposes no attack surface to the outside world, so it guarantees the security of itself to the greatest extent. In addition, it solves the antivirus storm problem and the rollback vulnerability problem in virtualization environment. We implemented a prototype based on Qemu/KVM hypervisor and ClamAV antivirus engine. Experimental results demonstrate that VirtAV is able to detect both user-level and kernel-level virus programs inside Windows and Linux guest, no matter whether they are packed or not. From the performance aspect, the overhead of VirtAV on guest performance is acceptable. Especially, VirtAV has little impact on the performance of common desktop applications, such as video playing, web browsing and Microsoft Office series.

• 대한한방내과학회지
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• 제37권4호
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• pp.678-684
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• 2016

Objectives: This clinical study describes the effect of Korean medicine on a patient with alcohol-related dementia.Methods: A patient with cognitive disorder and memory impairment due to alcohol abuse was treated with the herbal medicine “Gami Gwibi-tang”, acupuncture, and moxibustion, together with basic Western medicine. The patient’s cognitive function was evaluated by the Mini-Mental State Examination-Korean (MMSE-K) and Clinical Dementia Rating (CDR). Brain Magnetic Resonance Imaging (MRI) was used to estimate the severity of structural brain damage.Results: Following treatment with Gami Gwibi-tang, patent’s MMSE-K score and CDR improved.Conclusion: This clinical case study provides evidence of the effect of Korean medicine, including Gwibi-tang-gami, on alcohol-related dementia.

• 대한한방내과학회지
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• 제42권5호
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• pp.1082-1093
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• 2021

Objective: Alzheimer's disease is characterized by progressive, irreversible brain damage and cognitive decline. Although the diagnosis and treatment of the prodromal symptoms of dementia are important, no treatment for mild cognitive impairment has been currently established. Herein, we report the case of an 80-year-old female patient with memory complaints treated with Gugijihwang-tang, a traditional Korean medicine herbal formula, as an add-on medication. Case Presentation: The patient was diagnosed with mild cognitive impairment based on clinical examinations using the Mini-Mental State Examination (MMSE), the Consortium to Establish a Registry for Alzheimer's Disease (CERAD), Activities of Daily Living (ADL) Scale, Global Deterioration (GDR) Scale, and Clinical Dementia Rating (CDR) Scale. She was treated with Gugijihwang-tang bis in die for 12 months while continuing her original medications, including 5-mg donepezil and 590-mg acetyl-l-carnitine. The MMSE score in the Korean Version of the CERAD Assessment Packet increased from 21 to 27 during the 12-month treatment period, and the CERAD 2 score increased from 33 to 62. The instrumental ADL scale score improved from 11 to 5. Other clinical examination results also showed improvement. The patient was satisfied and experienced no significant adverse events related to the Gugijihwang-tang treatment. Conclusion: This case suggests that Gugijihwang-tang could be considered as a treatment method for patients with mild cognitive impairment.

• 한국ITS학회 논문지
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• 제20권6호
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• pp.242-263
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• 2021

본 논문은 자율주행 알고리즘 개발을 위한 저비용 드라이빙 시뮬레이터 구축 방법을 소개한다. 이는 물리엔진을 적용한 상용게임 소프트웨어인 GTA V를 활용하여 구현되며 자율주행 시스템에 필요한 다양한 센서 출력값 및 데이터를 에뮬레이션하는 기능을 내장한다. 이를 위해 GTA V 내부 데이터를 취득할 수 있는 Script Hook V의 NF를 활용하여 GT 데이터를 취득하고, 이를 활용하여 다양한 자율주행용 센서 데이터를 생성한다. 본문에서는 설계된 드라이빙 시뮬레이터의 전반적인 기능들을 소개하며, 개별 기능에 대한 검증을 수행한다. 자율주행 알고리즘 개발 환경 구축을 위해 게임 엔진 내부 메모리 접근을 통한 GT 데이터를 취득하는 과정을 설명하고, 에뮬레이션된 센서값을 처리 및 활용하여 인공 신경망 학습 및 성능평가에 적용 가능한 예시를 제시한다.

• IMMUNE NETWORK
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• 제21권2호
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• pp.17.1-17.10
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• 2021

Abdominal aortic aneurysm (AAA) is a chronic dilation of the aorta with a tendency to enlarge and eventually rupture, which constitutes a major cause of cardiovascular mortality. Although T-cell infiltrates have been observed in AAA, the cellular, phenotypic, and functional characteristics of these tissue-infiltrating T cells are not fully understood. Here, we investigated the proportional changes of T-cell subsets-including CD4⁺ T cells, CD8⁺ T cells, and γδ T cells-and their effector functions in AAAs. We found that Vδ2⁺ T cells were presented at a higher frequency in aortic aneurysmal tissue compared to normal aortic tissue and PBMCs from patients with AAA. In contrast, no differences were observed in the frequencies of CD4⁺, CD8⁺, and Vδ1⁺ T cells. Moreover, we observed that the Vδ2⁺ T cells from AAA tissue displayed immunophenotypes indicative of CCR5⁺ non-exhausted effector memory cells, with a decreased proportion of CD16⁺ cells. Finally, we found that these Vδ2⁺ T cells were the main source of IL-17A in abdominal aortic aneurysmal tissue. In conclusion, our results suggest that increased Vδ2⁺ T cells that robustly produce IL-17A in aortic aneurysmal tissue may contribute to AAA pathogenesis and progression.

• 대중서사연구
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• 제26권1호
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• pp.175-209
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• 2020

본 논문은 일본군 '위안부'의 영화적 재현이 어떻게 일상의 영역에서, 그리고 대중의 기억 속에서 '상상력'을 촉발하고 공통의 감각과 정동을 불러일으키는가 살펴보자 한다. 일본군 '위안부' 역사는 오랫동안 망각되었다가 1990년대에 들어서야 공공 기억의 장으로 들어설 수 있었다. 이러한 전환에는 피해자들의 증언과 일본군 '위안부' 문제의 담론화를 가능하게 만든 국내외적 크로노폴리틱스(chronopolitics)가 존재한다. 이는 '시간의 정치학'으로서 일본군 '위안부' 역사의 독특한 위상을 보여주는데, 일본군 '위안부' 문제의 영화적 재현은 역사적 크로노폴리틱스와 연속적이면서도 단절적인 이중성을 보여주며 새로운 시각적 크로노폴리틱스를 드러낸다. 한국영화사의 맥락에서 일본군 '위안부' 재현의 크로노토프는 크게 4가지 국면으로 나누어 생각해 볼 수 있다. 첫째, 1990년대 이전 일본군 '위안부'의 극적 재현들, 둘째, 증언과 역사쓰기로서 1990년대 후반 다큐멘터리, 셋째, 2000년대 들어 멜로드라마적 감수성을 이끌어낸 극영화들, 넷째, 애니메이션 및 기타 장르를 포함하는 매체의 확산이다. 이들 중에서 '위안부' 문제를 대중적 극영화(fiction film)의 범주에서 표상하고 있는 첫 번째 국면과 세 번째 국면에 집중해 논의를 전개하는 것이 이 글의 목적이다. 1990년 이전의 '위안부' 극영화들이 철저히 상업영화와 대중장르의 틀을 고수하며 일본군 '위안부' 역사의 성애화를 추구했다면, 2000년대 이후의 영화들은 대중영화의 양식 속에서 다양한 시도들을 실험해보고 있다. 특히, <귀향>, <아이 캔 스피크>, <허스토리> 등과 같은 2000년대 '위안부' 극영화들의 등장은 우리가 그간 생존자들의 증언과 일본군 '위안부' 운동 등을 통해서 '많이' 알고 있다고 생각했던 이 이슈에 대하여 과연 우리가 '제대로' 알고 있는지, 이에 대한 '문화적 재현은 어떻게 가능한지' 등의 여러 문제를 제기해주고 있다. 일본군 '위안부'를 다룬 2000년대 영화적 재현의 전략들에 주목하면서, 이 글은 멜로드라마의 대중 정치학, 피해자성과 폭력의 재현, 메타기억으로서의 일본군 '위안부' 극영화 등을 논의하고자 한다. 역사적 트라우마에 대한 멜로드라마적 상상이자 메타기억으로서, '위안부' 극영화들은 일본군 '위안부' 문제가 통과해야 할 역사적, 정치적, 미학적 관문들을 보여준다. 보다 구체적으로 말하면, 최근의 극영화들에서 일본군 '위안부' 문제가 한-일 양국 간의 관계를 넘어서, 오래된 식민 구조를 해체하고자 하는 탈식민주의적 과제이자 여성운동과 인권운동이 국제적으로 연대하는 트랜스내셔널한 프로젝트로 거듭나는 방식에 이 글은 주목한다.

• 대한전기학회논문지:전기물성ㆍ응용부문C
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• 제49권12호
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• pp.665-672
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• 2000

This paper described the measurement technology to analyze the partial discharge characteristics for long term aging of insulations. This system was consisted of high voltage generation and measurement part, PD detection part, digital conversion and signal processing part. We used the VXI system for digital conversion and signal processing part. In the digital conversion part, we studied the error of partial discharge magnitude and memory capacity for reading digital signal with the sampling rate. In the signal processing part, we showed the program algorithm to count pulses and read peak values of partial discharge. The allowable minimum sampling rate of digizer was decided to 250kS/s through analyzing test. We confirmed that this system was very useful in the study of $\phi-q-n$ characteristics of long term PD experiments with specimens being consisted of internal void defects and CIGRE II electrodes.