• Journal of KIISE
• /
• v.44 no.11
• /
• pp.1231-1235
• /
• 2017

Given the network structure in online social network, it is important to determine a way to distinguish spam accounts from the network features. In online social network, the service provider attempts to detect social spamming to maintain their service quality. However the spammer group changes their strategies to avoid being detected. Even though the spammer attempts to act as legitimate users, certain distinguishable structural features are not easily changed. In this paper, we investigate a way to generate meaningful network structure features, and suggest spammer detection method using recursive structural features. From a result of real-world dataset experiment, we found that the proposed algorithm could improve the classification performance by about 8%.

• Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
• /
• v.22 no.2
• /
• pp.145-150
• /
• 2004

A protocol for the web-based GPS data processing system has been developed. The system is developed following the typical ASP system, in which the GPS data acquired by various users can be uploaded through the web and the data is processed with data processing components selected by the users. After the processing, the results are also transported to the users through the web. The developed system is designed for easy software upgrade and it is an synchronous process mode so that the multiple accesses can be handled with high user flexibility. The database components for the efficient GPS data maintenance are developed so that the data from CORS can be used for the data processing. Currently, the absolute and relative positioning algorithms using code measurements are integrated and much more algorithms such as the data quality control, absolute and relative positioning using phases will be integrated in near future.

• Proceedings of the Korean Society of Surveying, Geodesy, Photogrammetry, and Cartography Conference
• /
• 2003.04a
• /
• pp.81-92
• /
• 2003

A protocol for the web-based GPS data processing system has been developed. The system is developed following the typical ASP system, in which the GPS data acquired by various users can be uploaded through the web and the data is processed with data processing components selected by the users. After the processing, the results are also transported to the users through the web. The developed system is designed for easy software upgrade and it is an asynchronous process mode so that the multiple accesses can be handled with high user flexibility. The database components for the efficient GPS data maintenance are developed so that the data from CORS can be used for the data processing. Currently, the absolute and relative positioning algorithms using code measurements are integrated and much more algorithms such as the data quality control, absolute and relative positioning using phases will be integrated in near future.

• Journal of Internet Computing and Services
• /
• v.15 no.5
• /
• pp.123-132
• /
• 2014

Internet is composed of many independent networks referred to as Internet Service Providers (ISPs) and each provider is generally interconnected based on a commercial agreement. Though many countries are engaged in deregulation in internet interconnection, there is still debate whether the large ISPs are unwilling to peer with small providers, have incentives to lower the quality of data transmission of transit operators or set the interconnection charge regarding the actual costs incurred by the interconnection. Korean government introduced regulations in internet interconnection after observing noticeable anti-competitive behaviors from 2005. This paper analyzes whether there is margin squeeze problem/market concentration, and suggests political proposals in Korean regulation status.

• Journal of Communications and Networks
• /
• v.13 no.6
• /
• pp.591-601
• /
• 2011

Today's Internet which provides communication channels with best-effort end-to-end performance is rapidly evolving into an autonomic global computing platform. Achieving autonomicity in the Future Internet will require a performance architecture that (a) allows users to request and own 'slices' of geographically-distributed host and network resources, (b) measures and monitors end-to-end host and network status, (c) enables analysis of the measurements within expert systems, and (d) provides performance intelligence in a timely manner for application adaptations to improve performance and scalability. We describe the requirements and design of one such "Future Internet performance architecture" (FIPA), and present our reference implementation of FIPA called 'OnTimeMeasure.' OnTimeMeasure comprises of several measurement-related services that can interact with each other and with existing measurement frameworks to enable performance intelligence. We also explain our OnTimeMeasure deployment in the global environment for network innovations (GENI) infrastructure collaborative research initiative to build a sliceable Future Internet. Further, we present an applicationad-aptation case study in GENI that uses OnTimeMeasure-enabled performance intelligence in the context of dynamic resource allocation within thin-client based virtual desktop clouds. We show how a virtual desktop cloud provider in the Future Internet can use the performance intelligence to increase cloud scalability, while simultaneously delivering satisfactory user quality-of-experience.

• Journal of Distribution Science
• /
• v.15 no.6
• /
• pp.47-56
• /
• 2017

Purpose - The purpose of this study is to examine the viability of imitation strategy. Imitation strategy is one of the strategic options that a late mover can choose, and by selecting the strategy, the company imitates key elements of the business model of first movers, and modifies them to suit its conditions. The author attempted to explain how the elements of first mover's business models were creatively adapted to suit the conditions of late movers so that they can secure market position face-to-face market leaders. Research design, data, and methodology - For the purpose of the study, Korean coffee franchise industry was selected to compare the strategies of first and late movers and to discuss imitation strategy in detail. The author conducted in-depth case study of first mover and business model innovator Starbucks and Ediya Coffee, one of their imitators. The paper examines how Ediya has imitated and modified the business model of Starbucks to secure its unique competitive position in domestic market by using value chain and generic strategy analysis. Results - Starbucks and Ediya were compared in terms of their interior design, the price level of beverages, the variety of side dishes, and shop locations. Starbucks have invested interior design heavily to shops, offered diverse beverages and side dishes with relatively high price, the shops are located in central areas, whereas Ediya has concentrated on achieving cost leadership in all value activities as maintaining the quality of key products. Ediya succeeded in achieving best-provider strategy, in which it enjoys both cost leadership and differentiation advantages, largely by the strategic alliance with the biggest coffee manufacturer, Dongsuh Foods in Korea. Conclusions - Though Ediya is the imitator of Starbucks, it has modified Starbucks business models and succeeded in providing the 'third place' experience for budget-minded customers. Ediya has also succeeded in benefiting its franchisees by lowering costs and simplifying the various tasks of coffee shop management. Due to these factors, Ediya could become one of the largest number shops as the coffee franchise in Korea.

• The KIPS Transactions:PartC
• /
• v.19C no.2
• /
• pp.145-148
• /
• 2012

In a distributed streaming system using an advanced coding scheme that encodes a video into multiple substreams, the capacity of the system depends on the amount of contribution of participating peers. Thus, an incentive mechanism for peers to contribute voluntarily is needed to increase system capacity. In addition, since peers are not only a provider but also a consumer in the system (i.e. prosumer), the overall capacity of the system must be allocated fairly among the peers while it must be allocated in a way that can maximize the net quality of experience of peers to increase system efficiency. In this paper, we propose a substream allocation method to solve the problems taking an optimization approach. Unlike the other optimization approaches, the proposed method is verified quantitatively in a simulation study that it can use the capacity of video streaming system efficiently while allocating fair amount of substreams among peers because it considers explicitly the prosumer characteristics of peers.

• Journal of Digital Contents Society
• /
• v.18 no.3
• /
• pp.535-542
• /
• 2017

The ubiquitous computing made it happen to easily take cognizance of context, which includes user's location, status, behavior patterns and surrounding places. And it allows providing the catered service, designed to improve the quality and the interaction between the provider and its customers. The personalized recommendation service needs to obtain logical reasoning to interpret the context information based on user's interests. We researched a model that connects to the practical value to users for their daily life; information about restaurants, based on several mobile contexts that conveys the weather, time, day and location information. We also have made various approaches including the accurate rating data review, the equation of Naïve Bayes to infer user's behavior-patterns, and the recommendable places pre-selected by preference predictive algorithm. This paper joins a vibrant conversation to demonstrate the excellence of this approach that may prevail other previous rating method systems.

• Journal of Digital Convergence
• /
• v.13 no.5
• /
• pp.297-307
• /
• 2015

This study reviews equipped with enhanced capability of medical care, quality service, accessibility, and consumer awareness to be a competitive and representative local healthcare service provider with improved administrative efficiency. The method of analysis are ANOVA and Structural Equation Modeling. The results which revealed the significant difference among demographic factors in determining the preference or degree of satisfaction at medical service to select local healthcare institutions suggest that the close review on the needs of groups of major customers of local healthcare institutions are necessary when preparing the strategy of specialized medical service of local healthcare institutions. this suggests that both images would be important factors to secure the competitive advantage of local healthcare institution and therefore the strategy maximized the enhancement of medical service with embossed image of hospital to attract customers of medical service is needed.

• Journal of the Korea Society for Simulation
• /
• v.23 no.1
• /
• pp.1-10
• /
• 2014

A cloud computing is one of a parallel and distributed computing. The cloud computing provides some service for user with virtual resources. However, a user's service request does not show a time pattern. As a result, each resource also shows a different availability at the same time. This difference affects a quality of service (QoS) and a resource selection for users. Therefore, we propose the resource availability-based multi auction model for cloud service reservation and resource brokering system. The proposed system is to select the proper resource provider based on the users' request. The proposal adopts the multi phase of the auction to transact resources. The system evaluates the available factor of each resource on the auction phase, and finally reserves the service on the adaptive queue. The proposed model shows the better performance than other existing method.