• Journal of Information Processing Systems
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• v.14 no.2
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• pp.455-468
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• 2018

The concepts of graph theory are applied to model and analyze dynamics of computer networks, biochemical networks and, semantics of social networks. The analysis of dynamics of complex networks is important in order to determine the stability and performance of networked systems. The analysis of non-stationary and nonlinear complex networks requires the applications of ordinary differential equations (ODE). However, the process of resolving input excitation to the dynamic non-stationary networks is difficult without involving external functions. This paper proposes an analytical formulation for generating solutions of nonlinear network ODE systems with functional decomposition. Furthermore, the input excitations are analytically resolved in linearized dynamic networks. The stability condition of dynamic networks is determined. The proposed analytical framework is generalized in nature and does not require any domain or range constraints.

• Journal of the Korean Geographical Society
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• v.48 no.3
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• pp.366-386
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• 2013

This paper analyzes the drought and restriction on water supply in Taebaek City during the winter season in 2008 using Actor-Network Theory. Actor-Network Theory emphasizes and brings into view the role and act of non-human actors as well as human actors in various environmental issues. The fact that only Taebaek experienced restriction on water supply for 88 days although the winter season drought in 2008 affected the whole nation, requires a synthetic analysis of both human and non-human actors and their relationships and networks embedded in Taebaek City at that time. This paper shows that both human and non-human actors including Taebaek City Hall, Korea Water Resource Corporation, Taebaek citizen, the water supply facilities, Gwangdongdam, obsolete water pipes, the topography of Taebaek, soil, the change of industry, and population interact one another transforming the geography of water in Taebaek. This study helps to understand the complex processes related to drought disasters at a specific local scale and to provide appropriate measures to drought.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2013.05a
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• pp.199-201
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• 2013

In a construction project in which cooperation among project members gets its importance, trust among construction site members should be foundation to enhance team spirit and achievement. This study analyzes the trust network among staff by using social network analysis (SNA) theory for organizations in apartment complex construction sites in Korea. The analysis illustrates higher level of trust for those positioning in the higher positions in hierarchy and having greater experiences. It might be attributable to own features of construction works where skills are acquired by site experience.

• International Journal of Computer Science & Network Security
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• v.21 no.12
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• pp.9-20
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• 2021

Abstraction applied in computer networking hides network details behind a well-defined representation by building a model that captures an essential aspect of the network system. Two current methods of representation are available, one based on graph theory, where a network node is reduced to a point in a graph, and the other the use of non-methodological iconic depictions such as human heads, walls, towers or computer racks. In this paper, we adopt an abstract representation methodology, the thinging machine (TM), proposed in software engineering to model computer networks. TM defines a single coherent network architecture and topology that is constituted from only five generic actions with two types of arrows. Without loss of generality, this paper applies TM to model the area of network monitoring in packet-mode transmission. Complex network documents are difficult to maintain and are not guaranteed to mirror actual situations. Network monitoring is constant monitoring for and alerting of malfunctions, failures, stoppages or suspicious activities in a network system. Current monitoring systems are built on ad hoc descriptions that lack systemization. The TM model of monitoring presents a theoretical foundation integrated with events and behavior descriptions. To investigate TM modeling's feasibility, we apply it to an existing computer network in a Kuwaiti enterprise to create an integrated network system that includes hardware, software and communication facilities. The final specifications point to TM modeling's viability in the computer networking field.

• Korean Journal of Acupuncture
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• v.29 no.3
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• pp.431-440
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• 2012

Objectives : Recently, network science is very popular topic in various scientific fields and many studies have reported that it gives meaningful results on studying characteristics of a complex system. In this study, based on network theory, we made acupoints network using data of combined acupoints which appeared at "Beijiqianjinyaofang". We focused to find out the distinctive roles of remote and local combinations on the network. Furthermore, we aimed to identify the possibility of numerical and quantitative application to acupuncture researches. Methods : Based on examples of combined acupoints in "Beijiqianjinyaofang", the network consisted of 291 nodes and 2,431 links. The spatial distances between combined acupoints were calculated by the human dummy model. We removed the links step by step for the three cases - remote, local, and random cases, and observed the characteristic changes by calculating path lengths, similarity indices, and clustering coefficients. Also cluster analysis was carried out. Results : The network had a small number of remote links, and a large number of local links. These two links had the distinct characteristics. Whereas the local links formed a cluster of nearby nodes, remote links played a role to increase the correlation between the clusters. Conclusions : These results suggest that acupoints network increases the connectivity between the distal part and the trunk of human body, and enables various combinations of the acupoints. This finding conclusively showed that mechanism of combined acupoints could be interpreted meaningfully by applying network theory in acupuncture researches.

• International Journal of Computer Science & Network Security
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• v.24 no.5
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• pp.172-180
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• 2024

Since the beginning of 2015, corporate social responsibility (CSR) models have been changing in connection with the trend towards the transition of joint value creation of corporate activities and consideration of stakeholders' interests. The purpose of the academic paper lies in empirically studying the current practice of social responsibility of transnational corporations (TNCs). The research methodology has combined the method of qualitative analysis, the method of cases of agricultural holdings in emerging markets within the framework of resource theory, institutional theory and stakeholders' theory. The results show that the practice of CSR is integrated into the strategy of sustainable development of TNCs, which determine the methods, techniques and forms of communication, as well as areas of stakeholders' responsibility. The internal practice of CSR is aimed at developing norms and standards of moral behaviour with stakeholders in order to maximize economic and social goals. Economic goals are focused not only on making a profit, but also on minimizing costs due to the potential risks of corruption, fraud, conflict of interest. The system of corporate social responsibility of modern TNCs is clearly regulated by internal documents that define the list of interested parties and stakeholders, their areas of responsibility, greatly simplifying the processes of cooperation and responsibility. As a result, corporations form their own internal institutional environment. Ethical norms help to avoid the risks of opportunistic behaviour of personnel, conflicts of interest, cases of bribery, corruption, and fraud. The theoretical value of the research lies in supplementing the theory of CSR in the context of the importance of a complex, systematic approach to integrating the theory of resources, institutional theory, theory of stakeholders in the development of strategies for sustainable development of TNCs, the practice of corporate governance and social responsibility.

• Journal of Korean Tunnelling and Underground Space Association
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• v.19 no.2
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• pp.213-229
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• 2017

Recently, in urban areas there is a tendency to construct more complex network-type tunnels including entrance and exit ramps. At the same time, various one-dimensional programs based on the network theory have been proposed for tunnel ventilation analysis. This paper aims at developing a program that can analyze the ventilation flow rate and pollutants concentration in complex network-type tunnels based on the none hardy-cross method. The flow analysis in the branch was carried out on the basis of the Gradient method, while for the concentration analysis a new logic has been developed to calculate the inflow and outflow concentration automatically in a complex network-type structure. Additionally, in the tunnel segments showing low flow rate, proper grid interval sizes were proposed to reduce numerical error. To verify the applicability of the program, flow rates predicted in the straight tunnels were compared with the classical velocity-diagram method by Stokic and the TVSDM program. The results showed that the errors were within 1%. In addition, the program was applied to the recent ventilation system adopted in the complex network-type urban tunnels.

• Journal of Urban Science
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• v.12 no.1
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• pp.21-34
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• 2023

Based on the theory of network governance, this study aims to establish a n'work governance model and present strategic measures for the use of return donor zones. In a network society, it is difficult for the government to handle complex problems alone, so close cooperation between related agencies has become important. After the return of the USFK base, most of the policies established by the government have not been carried out smoothly, so it is necessary to introduce cooperative network governance.Accordingly, technical statistics were analyzed for camp market business institutions to examine the centrality and structure of network relations (information sharing relationship, idea exchange relationship, civil complaint sharing relationship). As a result of the analysis, the Camp Market Division of Incheon City had the most central role and great influence in the camp market, which was maintained even when the time changed. Currently, it is in the form of a vertical network centered on local governments, but in the future, a horizontal network is suitable to strengthen cooperative relations and must be systematically managed around managers.

• Industrial Engineering and Management Systems
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• v.10 no.4
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• pp.238-246
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• 2011

Given a directed graph, we can determine how the user's preference moves from one product item to another. In this graph called "preference transition network", each node represents the product item while its edge pointing to the other nodes represents the transition of user's preference. However, with the large number of items make the network become more complex, unclear and difficult to be interpreted. In order to address this problem, this paper proposes a visualization technique in preference transition analysis based on recency and frequency. By adapting these two elements, the semantic meaning of each item and its transition can be clearly identified by its different types of node size, color and edge style. The experiment in a sales data has shown the results of the proposed approach.

• Transactions of the Korean Society for Noise and Vibration Engineering
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• v.13 no.6
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• pp.445-451
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• 2003

Booming sound is one of the most important interior sound of a passenger car. The conventional booming noise research was focused on the reduction of the A-weighted sound pressure level. However A-weighted sound pressure level cannot give the whole story about the booming sound of a passenger car. In this paper, we employed sound metrics, which are the subjective parameters, used in psycoacoustics. According to recent research results. the relation between sound metrics and subjective evaluation is very complex and has nonlinear characteristics. In order to estimate this nonlinear relationship, artificial neural network theory has been applied to derivation of sound quality index for booming sound of a passenger car.