• Journal of KIISE:Computer Systems and Theory
• /
• v.28 no.1_2
• /
• pp.11-19
• /
• 2001

근래에 들어, 백플레인 버스를 기반으로 하는 멀티프로세서 시스템의 프로세서간 통신에도 TCP/IP와 같은 표준 네트워크 프로토콜을 이용하여 표준 MAC 계층을 구현하는 것이 일반적이다. 본 논문은 이러한 MAC 에뮬레이션 기반 버스 네트워크상에서 내장형 실시간 은용을 지원하기 위한 최악 응답 시간 분석법을 제시한다. 본 논문의 분석법은 구체적으로 MAC 에뮬레이션 방법의 하나인 ANSI BusNet 프로토콜을 대상으로 진행된다. 각 실시간 태스크를 주기, CPU 시간, 종료시한, 메시지 패킷 개수로 모델링하고 스케쥴 가능성, 즉 주어진 종료 시한 내에 작업을 완료할 수 있는지의 여부를 검사하는 수식을 유도한다. 이를 위해 물리적인 버스 특성을 고려한 버스 전송 모델을 제시하고, 버스 중재 방식과 버스 하드웨어의 캐슁 지원 여부에 따른 스케쥴 가능성을 분석한다. 또한 본 논문에서는 실험을 통해 블록 전송이 실시간 통신 성능에 미치는 영향을 살펴본다. 비록 본 논문의 분석법이 BusNet에 기반하여 개발되었지만, BusNet이 대부분의 백플레인 하드웨어가 지원하는 기본적인 기능만을 가정하고 있으므로, 본 논문의 분석법은 다른 종류의 백플레인 네트워크 프로토콜에도 쉽게 적용될 수 있다.

• Proceedings of the Korea Information Processing Society Conference
• /
• 2004.05a
• /
• pp.1007-1010
• /
• 2004

본 논문에서는 분산 서비스거부 공격(DDoS)이 발생할 때 네트워크 트래픽의 특성을 분석하기 위해서 트래픽 비율분석법(TRA: Traffic Rate Analysis)을 제안하고 트래픽 비율분석법을 통해서 분석된 다양한 유형의 DDoS 공격의 특성을 기계학습(Machine Learning)을 이용해서 DDoS 공격의 탐지규칙을 생성하고 그 성능을 측정하였다. 트래픽 비율분석법은 감시대상 네트워크 트래픽에서 특정한 유형의 트래픽의 발생비율을 나타내며 TCP flag rate 와 Protocol rate 로 구분된다. 트래픽 비율분석법을 적용한 결과 각각의 DDoS 공격 유형에 따라서 매우 독특한 특성을 가짐을 발견하였다. 그리고, 분석된 데이터를 대상으로 세 개의 기계학습 방법(C4.5, CN2, Na?ve Bayesian Classifier)을 이용해서 DDoS 공격의 탐지규칙을 생성하여 DDoS 공격의 탐지에 적용했다. 실험결과, 본 논문에서 제안된 트래픽 비율분석법과 기계학습을 통한 DDoS 공격의 탐지방법은 매우 높은 수준의 성능을 나타냈다.

• Journal of Korean Society of Transportation
• /
• v.27 no.1
• /
• pp.191-200
• /
• 2009

This study develops composite indicators that is capable of estimating QOS (Quality of Service) of pedestrians by enhancing estimation for Level of Service in present transporting spaces for pedestrians that merely concerns quantitative indicators such as pedestrian flow rate, pedestrian stoppage. This paper conducts survey questionnaire to collect data. It utilizes AHP(Analytic Hierarchy Process) and ANP(Analytic Network Process). The main results show that: first, ANP is better analytic methods than AHP due to the fact that pedestrians feel repetition when they judge level of service. Second, qualitative factors such as pedestrian behaviors, maintenance, scenary for pedestrians and environments should be considered. Importance of qualitative factors is higher in residential area than other areas. I expect that using qualitative indicators and quantitative indicators is appropriate in order to estimate pedestrians' QOS.

• Journal of the Korea Society of Computer and Information
• /
• v.13 no.4
• /
• pp.169-175
• /
• 2008

The existing block encryption algorithms have been designed for the encryption key value to be unchanged and applied to the round functions of each block. and enciphered. Therefore, it has such a weak point that the plaintext or encryption key could be easily exposed by differential cryptanalysis or linear cryptanalysis, both are the most powerful methods for decoding block encryption of a round repeating structure. Dynamic cipher has the property that the key-size, the number of round, and the plaintext-size are scalable simultaneously. Dynamic network is the unique network satisfying these characteristics among the networks for symmetric block ciphers. We analyze the strength of Dynamic network for meet-in-the-middle attack, linear cryptanalysis, and differential cryptanalysis. Also, In this paper we propose a new network called Dynamic network for symmetric block ciphers.

• The Journal of the Convergence on Culture Technology
• /
• v.6 no.1
• /
• pp.313-320
• /
• 2020

The aim of this study is to analyze the structural factors of cosponsorship network in the National Basic Livelihiid Security Legislative Revision. This study use ERGM method and Korea Congress Data. The result of the analysis shows outlet effect and transilative effect is negative. It suggests that inactivaion of the congress on the public welfare.

• Proceedings of the KAIS Fall Conference
• /
• 2010.05b
• /
• pp.803-806
• /
• 2010

저고용을 통한 고효율로 기업생산성을 추구하는 결과, 야기되는 고용의 불균형을 타개하기 위해 2007년 정부는 사회적 기업 육성법을 통해 사회적 기업을 장려하고 있다. 뿐 만 아니라 전 세계적 으로도 사회적 기업에 관련된 연구를 미국의 로버츠 재단, 영국의 Social Firms, EMES European Research Network 등이 중심이 되어 사회적 기업의 생존 전략과 사회적 자본 활용을 통한 발전방법을 모색하고 있다. 본 연구는 이러한 세계적인 추세에 발맞추어 사회적 기업 발전에 필요한 기업생존, 고용증대, 매출증대, 권한위임을 종속변수로 Granovetter Mark, Burt Ronald, Coleman James, Peter Witt, Andreas Schroeter, Christin Merz, Helen Haugh 등의 연구를 참고하여 독립변수인 네트워크다양성과 강도가 어떻게 작용하는지를 먼저 실증 분석하고 나아가 네트워크의 효율적인 운영을 통하여 사회적 기업 발전을 극대화시키는데 연구목적이 있다. 그리고 본연구의 대상은 2009년 현재 국내의 295개 사회적 기업 가운데 전문가의 추천을 받은 25개 회사로 이루어졌으며 SPSS 12.0으로 요인분석, 타당성, 신뢰성, 상관관계 등의 분석을 거쳐 다중회귀분석을 통하여 가설을 검증하였다. 검증의 결과 기업생존, 고용증대, 매출증대, 권한위임 전 과정에 네트워크가 필요하며 특히, 기업생존을 위해서는 네트워크강도에 관련된 요인을 매출증대를 위해서는 네트워크다양성에 관련된 요인을 잘 관리하고 유지 발전시켜야 함을 알 수 있었다. 끝으로 본 연구의 결과가 사회적 기업 창업을 준비 중인 국내의 많은 회사나 비영리법인, 사회단체가 계속기업으로 발전해 가기위한 사회적 자본 활용 전략에 많은 도움을 줄 수 있을 것으로 생각한다.

• KSCE Journal of Civil and Environmental Engineering Research
• /
• v.29 no.2D
• /
• pp.191-197
• /
• 2009

This study choose the Criteria by conducting survey questionnaire of expertise, ANP analysis, and reviewing literature to samples of School Zone in a synthetic and reasonable way. It draws the estimating factors including a variety of existing aspects (user, facility, operation and management, and education and institution) from the analyses and applies ANP to reflect the decision making process. The results show as follows: first, first level of weights presents proportion of 'facility' and 'user' takes 65% of total weights. It implies that the facility protects children from obstacles is the top priority of the settings. second, the second level of weights present similar importance with the first level. Facility management, road to school, surroundings, safety facility, decelerating facility hold approximately 72% of overall levels. This indicates that improving and repairing surroundings, and safety and decelerating facility are the first priority to consider. These estimating indicators will be properly utilized to rationally appoint prevention zone with reflecting various factors and social class.

• Journal of Korea Water Resources Association
• /
• v.41 no.4
• /
• pp.405-412
• /
• 2008

Rainfall quantiles were estimated by applying the FORGEX method. The circle network and two elliptical ones with the ratios of 1 to 1.5 and 1 to 2.0 were used and compared to find appropriate one for rainfall data. Annual maximum data were collected from 376 sites and standardized by the median. The networks were organized from the subject sites and then pooled and netmax data were collected from each network. Then, the growth curves and quantiles were estimated. When the subject site had small differences of quantiles from index flood method and at-site frequency analysis, those of the estimated quantiles from circle and elliptical networks were small. In contrast, the sites where the quantile differences are big have big differences of quantiles from circle and elliptical networks. The estimated quantiles from the elliptical network are more accurate than those from the circle network, because the ellipse network contains more sites in South Korea. Moreover, the ellipse with ratio of 1 to 2.0 shows closer quantiles to those from index flood method than one with ratio of 1 to 1.5. It is, therefore, found that the FORGEX method with 1 to 2.0 ellipse network is appropriate regional frequency analysis in South Korea.

• Journal of The Korean Association For Science Education
• /
• v.32 no.5
• /
• pp.823-840
• /
• 2012

The importance of teaching the nature of science (NOS) has been emphasized in the science curriculum, especially in the science curriculum for science-gifted students. Nevertheless, few studies concerning the structure and formation of students' mental model on NOS have been carried out. This study aimed to explore science-gifted students' understanding of 'fact', 'hypothesis', 'theory', 'law', and 'scientificness' by utilizing semantic network analysis. One hundred ten science-gifted middle school students who were selected by a national university participated in this study. We collected students' written responses of five items and analyzed them by the semantic network analysis(SNA) method. As a result, the core ideas of students' understanding of 'fact' were proof and reality, of 'hypothesis' were tentativeness and uncertainty, of 'theory' was proven hypothesis by experimentation, of 'law' were absoluteness and authority, and of 'scientificness' were factual evidence, verifiability, accurate and logical theoretical framework. The result of integrated semantic network illustrated that the viewpoint of science-gifted students were similar to absolutism and logical positivism (empiricism). Methodologically, this study showed that the semantic network analysis method was an useful tool for visualization of students' mental model of scientific conceptions including NOS.

• Journal of the Korean Society of Marine Environment & Safety
• /
• v.24 no.2
• /
• pp.163-170
• /
• 2018

The purpose of this study is to describe quantitatively the characteristics and the structure of the Act on the development, management, etc. of Marinas (the Marinas Act) by analysing its provisions using semantic network analysis. The method of semantic network analysis has its advantages in overcoming limitations of the traditional content analysis method, as it is easy for the user to understand the structure and the shape of a network by figuring out the structural network among words. The object of the analysis is the full text of Marinas Act recently revised from Chapters 1 to 4, while partial analysis is carried out respectively for each chapter from Chapters 2 to 4. The structural characteristic of the Marinas Act shows that the act focuses on the development of marinas, as its main goal is interpreted to set up hardwares and to construct facilities rather than to promote the marina industry itself. Even though some clauses for human capital development and business development are included, they are of less importance compared to the development of marina facilities. This study provides some basic information on the structural characteristics of the current act, which can be referred to in subsequent studies. In the future, it also needs to be complemented through comparative analysis with government policy outcomes and performance of diverse analytical approaches.