• Journal of Korean Society on Water Environment
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• v.24 no.4
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• pp.480-487
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• 2008

Spatial and temporal analyses of water qualities were performed for 11 monitoring stations located in Mangyung watershed in order to analyze the trends of monthly water quality data of Biochemical Oxygen Demand (BOD), Total Nitrogen (TN) and Total Phosphorus (TP) measured from 1995 to 2004. The long-term trends were analyzed utilizing Seasonal Mann-Kendall test, LOWESS and three-dimensional graphs were constructed with respect to distance and time. The graph can visualize spatial and temporal trend of the long-term water quality in a large river system. The results of trend analysis indicated that water quality of BOD and TN showed the downward trend. This quantitive and quantitative analysis is the useful tool to analyze and display the long-term trend of water quality in a large river system.

• Knowledge Management Research
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• v.17 no.1
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• pp.1-16
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• 2016

The purpose of this study is to analyze 352 scholarly journals and 1496 keywords in Knowledge Management Research from 2000 to 2015 and provide systematical view point of research trend in the area of knowledge management using graph theory and network model. The relational patterns among keywords as well as keywords which recently received noticeable attention and keywords which receded from the spotlight in recent years in the knowledge management literature were identified. The result of this study can be used as a foundation of future research ideas in knowledge management.

• Journal of the Korean Chemical Society
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• v.63 no.6
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• pp.473-485
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• 2019

In this study, we investigated the differences of graph constructed by middle school students in daily-life and scientific contexts according to the views on the nature of scientific measurement. A test consisting of three similar data sets regarding daily-life and scientific contexts was developed, and administered to 151 ninth graders. They were expected to construct proportional, inverse-proportional, and increasing and become constant form of graphs for each data set. Graphs constructed were analyzed in the aspects of constructing a trend line (types of a trend line, interpolation/extrapolation), selecting axes variables, scaling axes, and plotting points. Analyses of the results revealed that the students with set paradigm tended to construct a curved trend line, while those with point paradigm constructed a broken trend line in inverse-proportional graph questions. In the aspects of interpolation/extrapolation, most students with set paradigm performed both interpolation and extrapolation better than those with point paradigm in scientific context. Most students with set paradigm performed both interpolation and extrapolation regardless of contexts, while the proportion of interpolation of those with point paradigm was higher in scientific context than in daily-life context. In selecting axes variables, scaling axes, and plotting dots, there were no statistically significant differences between set and point paradigms. On the bases of the results, educational implications for improving graph construction skills of middle school students are discussed.

• Journal of Korean Society of Industrial and Systems Engineering
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• v.8 no.11
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• pp.1-16
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• 1985

This study is to systematize a flow of production activities with a formula to help understand the trend of production in an enterprise according to the profit graph. Although the existing methods of studies were unattainable to analyze earnings correlative to production due to the lack of total business management, this study is aimed at testing a new method that developed the method of an advanced analysis as well as a combined system of the profit graph. and the production trend.

• KIISE Transactions on Computing Practices
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• v.23 no.8
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• pp.473-480
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• 2017

In recent years, semiconductor-based storage devices such as flash memory (SSDs) have been developed to high performance. In addition, a trend has been observed of optimally utilizing resources such as the central processing unit (CPU) and memory of the internal controller in the storage device according to the needs of the application. This concept is called In-Storage Processing (ISP). In a storage device equipped with the ISP function, it is possible to process part of the operation executed on the host system, thus reducing the load on the host. Moreover, since the data is processed in the storage device, the data transferred to the host are reduced. In this paper, we propose a method to optimize graph query processing by utilizing these ISP functions, and show that the optimized graph processing method improves the performance of the graph 500 benchmark by up to 20%.

• Journal of The Korean Association For Science Education
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• v.25 no.2
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• pp.122-132
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• 2005

Graphing abilities are critical to understand and convey information in science. And then, to what extent are secondary students in science courses able to understand line graphs? To find clues about the students' interpretation processes of the information in science-related line graphs, this study has the following research question: Is there a difference between the levels of complexity of good and poor readers as they use the thinking aloud method for studying cognitive processes? The present study was designed to provide evidence for the hypothesis that good line graph readers use a specific graph interpretation process when reading and interpreting line graphs. With the aid of the thinking aloud method we gained deeper insight into the interpretation processes of good and poor graph readers while verifying verbal statements with respect to line graphs. The high performing students tend to read much more information and more trend-related information than the low performing students. We support the assumption of differential line graph schema existing in the high performing students in conjunction with general graph schema. Also, high performing students tend to think aloud much more metacognitively than low performing students. High performing students think aloud a larger quantity of information from line graphs than low performing students, and more trend-related sentences than value-related sentences from line graphs. The differences of interpretation processes revealed between good and poor graph readers while reading and interpreting line graphs have implications for instructional practice as well as for test development and validation. Teaching students to read and interpret graphs flexibly and skillfully is a particular challenge to anyone seriously concerned with good education for students who live in an technological society.

• Journal of The Korean Association For Science Education
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• v.39 no.5
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• pp.655-668
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• 2019

In this study, we investigated the middle school students' processes of scientific graph construction from the perspective of the problem solving process. Ten 9th graders participated in this study. They constructed a scientific graph based on pictorial data depicting precipitation reaction. The think-aloud method was used in order to investigate their thinking processes deeply. Their activities were videotaped, and semi-structured interviews were also conducted. The analysis of the results revealed that their processes of scientific graph construction could be classified into four types according to the problem solving strategy and the level of representations utilized. Students using the structural strategy succeeded in constructing scientific graph regardless of the level of representation utilized, by analyzing the data and identifying the trend based on the propositional knowledge about the target concept of the graph. Students of random strategy-higher order representation type were able to succeed in constructing scientific graph by systematically analyzing the characteristics of the data using various representations, and considering the meaning of the graph constructed in terms of the scientific context. On the other hand, students of random strategy-lower order representation type failed to construct correct scientific graph by constructing graph in a way of simply connecting points, and checking the processes of graph construction only without considering the scientific context. On the bases of the results, effective methods for improving students' ability to construct scientific graphs are discussed.

• Journal of the Korea Society of Computer and Information
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• v.28 no.5
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• pp.57-66
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• 2023

In this paper, a research trend of attack graph studies for Cyber-Physical System (CPS) environments is surveyed, and we analyse the limitations of previous works and prospect the future directions. 35 among around 150 attack graph studies conducted within 5 years target CPS, and we inspect key features of CPS environment in the security aspect. Also, we categorize and analyze target studies in the aspect of modelling physical systems and considering air gaps, which are derived as key features of the security aspects of CPS. Half of 20 research that we surveyed do not reflect those two features, and other studies only consider one of the two features. In this circumstance, we examine challenges that attack graph studies on CPS environment face. Finally, we expect state-led studies or studies targeting open-spec commercial CPS will dominate.

• Journal of Internet Computing and Services
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• v.25 no.1
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• pp.69-78
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• 2024

Recently, consumers have shown an increasing tendency to seek information related to environmental, social, and governance (ESG) aspects in order to choose products with higher social value and environmental friendliness. In this paper, we proposes a product recommendation system applying ESG indicators tailored to the recent consumer trend of value-based consumption, utilizing a model called MultiSAGE that combines GraphSAGE and GAT. To achieve this, ESG rating data for 1,033 companies in 2022 collected from the Korea ESG Standard Institute and actual product data from N companies were transformed into a Heterogeneous Graph format through a data processing pipeline. The MultiSAGE model was then applied in machine learning to implement a recommendation system that, given a specific product, suggests eco-friendly alternatives. The implementation results indicate that consumers can easily compare and purchase products with ESG indicators applied, and it is anticipated that this system will be utilized in recommending products with social value and environmental friendliness.

• Proceedings of the Korean Society of Broadcast Engineers Conference
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• 2011.07a
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• pp.437-438
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• 2011

Spectral segmentation is a major trend in image segmentation. Specially, constrained spectral segmentation, inspired by the user-given inputs, remains its challenging task. Since it makes use of the spectrum of the affinity matrix of a given image, its overall quality depends mainly on how to design the graphical model. In this work, we propose a sparse, multi-layer graphical model, where the pixels and the over-segmented regions are the graph nodes. Here, the graph affinities are computed by using the must-link and cannot-link constraints as well as the likelihoods that each node has a specific label. They are then used to simultaneously cluster all pixels and regions into visually coherent groups across all layers in a single multi-layer framework of Normalized Cuts. Although we incorporate only the adjacent connections in the multi-layer graph, the foreground object can be efficiently extracted in the spectral framework. The experimental results demonstrate the relevance of our algorithm as compared to existing popular algorithms.