• Journal of KIISE:Software and Applications
• /
• v.37 no.5
• /
• pp.394-402
• /
• 2010

JavaScript is one of the most popular languages to develope web sites and web applications. Since applicationss written in JavaScript are sent to clients as the original source code, they are easily exposed to plagiarists. Therefore, a method to detect plagiarized JavaScript programs is necessary. The conventional program dependency graph(PDG) based approaches are not suitable to analyze JavaScript programs because they do not reflect dynamic features of JavaScript. They also generate false positives in some cases and show inefficiency with large scale search space. We devise a JavaScript specific PDG(JS PDG) that captures dynamic features of JavaScript and propose a JavaScript plagiarism detection method for precise and fast detection. We evaluate the proposed plagiarism detection method with experiment. Our experiments show that our approach can detect false-positives generated by conventional PDG and can prune the plagiarism search space.

• Journal of Elementary Mathematics Education in Korea
• /
• v.23 no.1
• /
• pp.75-92
• /
• 2019

The 2015 revised mathematics curriculum encourages students to use graphs in newspapers and the Internet as materials when teaching graphs, and to experience a series of statistical problem-solving processes that collect, classify, organize, graph and interpret data. The graphs that the students learn through traditional textbooks were a single type of graphs. In particular, the graphs of the 5th and 6th grade groups were only increased in numbers, but the basic concepts were repeated in the 3rd and 4th grades. Fortunately, from the 2009 revision curriculum, it is possible to select the graph suitable for the situation while comparing the characteristics of some graphs. In most cases, the graphs used in the real world are presented in the form of a compounded infographics. The purpose of this study is to analyze and analyze the manifestations of information processing competence elements emphasized in the 2015 revised curriculum through the statistical project class using the informal graphic in the fifth grade of elementary school. And we suggested a concrete class plan.

• The Journal of the Korea Contents Association
• /
• v.22 no.1
• /
• pp.35-46
• /
• 2022

Recently, with the development of network technologies, as IoT and social network service applications have been actively used, a lot of graph stream data is being generated. In this paper, we propose a graph compression scheme that considers the stream graph environment by applying graph mining to the existing compression technique, which has been focused on compression rate and runtime. In this paper, we proposed Incremental frequent pattern based compression technique for graph streams. Since the proposed scheme keeps only the latest reference patterns, it increases the storage utilization and improves the query processing time. In order to show the superiority of the proposed scheme, various performance evaluations are performed in terms of compression rate and processing time compared to the existing method. The proposed scheme is faster than existing similar scheme when the number of duplicated data is large.

• Proceedings of the Korean Information Science Society Conference
• /
• 2000.04a
• /
• pp.489-491
• /
• 2000

본 논문은 ATM(Abstract Timed Machine)으로 명세된 실시간 시스템을 검증하기 위한 방법을 기술한다. ATM은 임무 위급 시스템인 실시간 시스템을 명세, 분석, 검증하기 위한 정형기법이다. ATM은 모드와 전이, 포트로 구성된다. 다른 정형기법과 비교하여 ATM은 소프트웨어의 순환공학 과정에서 사용하기 위해 설계되었다. 역공학 과정에서 ATM은 계산 논리 뿐만 아니라 실시간 시스템의 실제 소스코드에 있는 설계나 환경정보를 표현할 수 있다. 이러한 목적을 위해 ATM은 다양한 모드를 사용한다. ATM을 사용한 실시간 시스템의 검증은 도달성 그래프를 생성함으로써 수행한다. 도달성 그래프는 상태와 시간을 추상화되고 압축된 형태로 표현할 수 있으며 그 결과 시간 속성을 지닌 상태 공간을 감소시킬 수 있다. 또한 시스템의 교착상태를 쉽게 발견할 수 있다. 본 논문은 ATM과 실행 모델, 도달성 그래프, 검증을 위한 속성 등을 기술하며 이들을 다른 정형 기법들과 예제를 통하여 비교한다.

• Proceedings of the Korean Vacuum Society Conference
• /
• 2013.08a
• /
• pp.224.2-224.2
• /
• 2013

본 연구에서는 CIGS박막 태양전지의 온도 및 시간 인가에 따른 전기적 특성 변화를 분석하였다. 실험에서는 온도 스트레스를 $25^{\circ}C$, $50^{\circ}C$, $100^{\circ}C$, $150^{\circ}C$, $200^{\circ}C$에서 각각 10시간씩 인가한 후에 Dark I-V와 C-V측정을 통해 전기적 특성 변화를 분석하였다. $25^{\circ}C$일 때를 초기 온도로 하여 특성을 측정한 것과 온도별로 노출시킨 후에 측정한 것을 비교했을 때 소자의 효율은 $100^{\circ}C$에서 감소하기 시작하였고, 인가한 온도가 높을수록 점점 많이 감소하는 모습이 나타났다. 이와 비슷하게 I-V그래프와 C-V그래프의 모습도 초기 값과 비교해서 변화하는 모습이 나타났고, 온도가 높아질수록 점점 변화하는 양이 증가하였다. I-V그래프에서 Diode ideality factor는 온도변화에 따라 초기 값 대비 증가하는 모습이 나타났다. 온도에 노출되기 전보다 노출된 후에 current와 capacitance가 감소하는 경향을 보이는데, 이는 온도의 영향으로 인해 소자의 결함이 증가하여 전하들의 반응에 영향을 주었기 때문으로 판단된다.

• Korean Journal of Microbiology
• /
• v.39 no.2
• /
• pp.67-75
• /
• 2003

One large topic in comparative genomics is to predict functional annotation by classifying protein sequences. Computational approaches for function prediction include protein structure prediction, sequence alignment and domain prediction or binding site prediction. This paper is on another computational approach searching for sets of homologous sequences from sequence similarity graph. Methods based on similarity graph do not need previous knowledges about sequences, but largely depend on the researcher's subjective threshold settings. In this paper, we propose a genome sequence clustering method of iterative testing and graph decomposition, and a simple method to calculate a strict threshold having biochemical meaning. Proposed method was applied to known bacterial genome sequences and the result was shown with the BAG algorithm's. Result clusters are lacking some completeness, but the confidence level is very high and the method does not need user-defined thresholds.

• Journal of Korea Society of Industrial Information Systems
• /
• v.10 no.2
• /
• pp.26-31
• /
• 2005

In this paper, we present the document summarizers which are simpler and more condense than the existing ones generally used in the web search engines. This method is a statistic-based summarization method using the concept of the complete graph. We suppose that each sentence as a vertex and the similarity between two sentences as a link of the graph. We compare this summarizer with those of Clustering and MMR techniques which are well-known as the good summarization methods. For the comparison, we use FScore using the summarization results generated by human subjects. Our experimental results verify the accuracy of this method, being about $30\%$ better than the others.

• School Mathematics
• /
• v.19 no.2
• /
• pp.345-367
• /
• 2017

The purpose of this study is to investigate the proportional reasoning of middle school students during the process of expressing and interpreting the graphs. We collected data from a teaching experiment with four 7th grade students who participated in 23 teaching episodes. For this study, the differences between student A and student B-who joined theteaching experiment from the $1^{st}$ teaching episode through the $8^{th}$ -in understanding graphs are compared and the reason for their differences are discussed. The results showed different proportional solving strategies between the two students, which revealed in the course of adjusting values of two given variables to seek new values; student B, due to a limited ability for proportional reasoning, had difficulty in constructing graphs for given situations and interpreting given graphs.

• Journal of KIISE
• /
• v.44 no.1
• /
• pp.78-83
• /
• 2017

Finding the densest subgraphs from social networks, such that people in the subgraph are in a particular community or have common interests, has been a recurring problem in numerous studies undertaken. However, these algorithms focused only on finding the single densest subgraph. We suggest a heuristic algorithm of the bottom-up type, which finds the densest subgraph by increasing its size from a given starting node, with the repeated addition of adjacent nodes with the maximum degree. Furthermore, since this approach matches well with parallel processing, we further implement a parallel algorithm on the MapReduce framework. In experiments using various graph data, we confirmed that the proposed algorithm finds the densest subgraphs in fewer steps, as compared to other related studies. It also scales efficiently for many given starting nodes.

• The KIPS Transactions:PartD
• /
• v.9D no.3
• /
• pp.337-344
• /
• 2002

Recently, there has been a lot of research on graph-type data because it can model seamless the application domains such as GIS, network, WWW, multimedia presentations etc., and domain in which the data sequence is important. In this paper, an efficient code system, called node code system, is proposed to evaluate paths of DAG in a multimedia presentation graph. The node code system assigns a unique binary string to each node of a graph. The comparison of node codes of two nodes tells the connectivity between the nodes without actual traversal of a graph. The method using the property of the node code system allows us to construct the paths between two nodes more efficiently than the method using conventional graph traversals. The algorithms to construct paths using the node code system are provided.