• Journal of the Institute of Electronics Engineers of Korea CI
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• v.42 no.5
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• pp.9-20
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• 2005

In this paper, we propose ubiTrack, a system which tracks users' location in indoor environments by employing infrared-based proximity method. Most of recently developed systems have focussed on performance and accuracy. For this reason, they adopted the idea of centralized management, which gathers all information in a main system to monitor users' location. However, these systems raise privacy concerns in ubiquitous computing environments where tons of sensors are seamlessly embedded into environments. In addition, centralized systems also need high computational power to support multiple users. The proposed ubiTrack is designed as a passive mobile architecture to relax privacy problems. Moreover, ubiTrack utilizes appropriate area as a unit to efficiently track users. To achieve this, ubiTrack overlaps each sensing area by utilizing the TDM (Time-Division Multiplexing) method. Additionally, ubiTrack exploits various filtering methods at each receiver and utilization module. The filtering methods minimize unexpected noise effect caused by external shock or intensity weakness of ID signal at the boundary of sensing area. ubiTrack can be applied not only to location-based applications but also to context-aware applications because of its associated module. This module is a part of middleware to support communication between heterogeneous applications or sensors in ubiquitous computing environments.

• Korean Journal of Agricultural and Forest Meteorology
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• v.6 no.2
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• pp.85-93
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• 2004

In recent years, technology has advanced so much, especially in the developed world, such that its application in development activities may be lagging behind. The lag between technological advances and its application affects agrometeorological science as well. This paper discusses technological advances that may be better used to communicate agrometeorological information. It is important to bear in mind that technological advances are only channels of communication that may be used to speed up the transference of information from the source to the user. The paper begins with a review of the definitions of 'communication' to put the discussion into context. After reviewing several papers, in simple terms, communication can be defined as the sharing of meaning. The paper also looks at operational communications channels and comes to a conclusion that operational communications channels are pretty much universal irrespective of the development level of a country, although some are more easily accessible in some parts of the world than others. The common communications channels include: newspapers, farming papers, radio, television, fax, email, mobile phones (SMS) and Internet web sites. As part of technological advances, mobile phones are becoming increasingly useful all over the world. In order to make better use of this technology, it is important far those that will use this technology to understand how the technology works, not necessarily in detail, but to be able to operate the technology and obtain the data they need. When it comes to constraints, communication of agrometeorological information requires a substantial amount of resources and it is generally expensive especially when sophisticated models must be operated.

• Management & Information Systems Review
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• v.35 no.2
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• pp.27-44
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• 2016

In recent year, graphic emoticons in MIM(Mobile Instant Messenger) play an important role not as a valuable communication methods, but as main business model for MIM service providers. Although the graphic emoticons in MIM are regarded as a commercial product, there has been little systematic research reflecting consumers' perspectives. In order to fill this theoretical and practice gap, the study is designed to explore the structural relationships among emoticon use motives, attitude, and purchasing intention to emoticons in context of MIM. The results showed that emoticon use motives in MIM were composed of two main factors, perceived usefulness and perceived enjoyment. And we also verified that both perceived usefulness and perceived enjoyment positively impact flow in communication with using emoticons and social influence. Lastly, flow and social influence were positively related to attitude toward using emoticons and attitude also was related to purchase intention to emoticons in MIM, positively. However, flow and social influence did not have a positive influence on purchase intention to emoticons directly. The implications and limitations of this study are also discussed.

• Journal of Intelligence and Information Systems
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• v.9 no.3
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• pp.155-175
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• 2003

In context of e-commerce, negotiation is a procedure to help negotiate between buyer and seller by adjusting their negotiation issues such as price and in terms of payment. We used intelligent agent and mobile device to promote new framework of e-commerce. Moreover, this framework can help buyers and sellers to carry their commercial transactions effectively. In regard to that issue, we need to carry out the research of negotiation agent that can be used in e-commerce fields. In this paper, we modeled the negotiation using CSP for the performance of agent in m-commerce environment. Furthermore we implemented interface for mobile device to extract buyer's requirement and preference easily Besides that we used utility function to make a decision for various evaluation functions and suggestions that are used for evaluation of negotiation issues. A difficulty of generating offer is dependent on the number of negotiation issues and the range of the values. Therefore, if any offer has a number of negotiation issues and the range of values are wide, the search space will be exponentially expanded. There have been many studies fur solving this problem, we applied those techniques to improve the agent's ability of negotiation. For example, a contract can be accomplished by exchanging seller and buyer's offer that is generated by agent to adjust the requisite profit for each party. Finally, we show the improvement of satisfaction as the negotiation is processed.

• Journal of the Korea Institute of Information Security & Cryptology
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• v.17 no.4
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• pp.115-129
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• 2007

The ubiquitous and autonomic computing environments is open and dynamic providing the universal wireless access through seamless integration of software and system architectures. The ubiquitous computing have to offer the user-centric pervasive services according to the wireless access. Therefore the roaming services with the predefined security associations among all of the mobile devices in various networks is especially complex and difficult. Furthermore, there has been little study of security coordination for realistic autonomic system capable of authenticating users with different kinds of user interfaces, efficient context modeling with user profiles on Smart Cards, and providing pervasive access service by setting roaming agreements with a variety of wireless network operators. This paper proposes a Roaming Coordinator-based security management framework that supports the capability of interoperator roaming with the pervasive security services among the push service based network domains. Compared to traditional mobile systems in which a Universal Subscriber Identity Module(USIM) is dedicated to one service domain only, our proposed system with Roaming Coordinator is more open, secure, and easy to update for security services throughout the different network domains such as public wireless local area networks(PWLANs), 3G cellular networks and wireless metropolitan area networks(WMANs).

• Journal of KIISE:Software and Applications
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• v.35 no.6
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• pp.386-391
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• 2008

Some spoken word errors that violate grammatical or writing rules occurs frequently in communication environments like mobile phone and messenger. These unexpected errors cause a problem in a language processing system for many applications like speech recognition, text-to-speech translation, and so on. In this paper, we proposed and implemented an automatic correction system of ill-formed words and word spacing errors in SMS sentences that has been the major errors of poor accuracy. We experimented three methods of constructing the word correction dictionary and evaluated the results of those methods. They are (1) manual construction of error words from the vocabulary list of ill-formed communication languages, (2) automatic construction of error dictionary from the manually constructed corpus, and (3) context-dependent method of automatic construction of error dictionary.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.13 no.11
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• pp.5458-5464
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• 2012

In LTE-Advanced that different networks coexist, it is considered that it is actually difficult to provide service continuity with a procedural and static control method applied to the existing voice service. This research suggests a resource management framework to support the service continuity effectively based on QoS support. In other words, as context information of mobile terminal and base station changes, set-up of related functions such as ISHO, cell selection, source allocation, load control, and QoS mapping is adapted; each function fits into the change, exchanges the process of reorganization, and interacts; these actions go toward to satisfy service continuity. For this aim, the sequence diagram between the function modules for supporting four kind of ISHO is described and then a scenario for ISHO is considered.

• Information Systems Review
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• v.14 no.1
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• pp.21-35
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• 2012

The rapid growth and popularity of Twitter have been one of the most influential phenomena in the era of social network system and the mobile internet, which also opens up opportunities for new business strategies; in particular, PR and marketing area. This study analyzed use of Twitter in terms of user characteristics and message attributes. Actual field data from the Twitter for PR and Marketing of a representative Korean IT company (Company "K") was used for this analysis. Research findings show that overall corporate twitter users show passive attitude in retweet behavior. Also, users who have relatively small network size (less than 1,000) are more active in retweet than power twitterians that have big network size(over than 10,000). It is showed that the rate of retweet is higher in the order of recruiting, promotional event, IT information, and general PR message. In the conclusion section, practical implications based on the research finding are thoroughly discussed.

• The Journal of Information Systems
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• v.24 no.2
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• pp.209-240
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• 2015

Purpose This study investigates the relationships between various attributes of smart banking (convenience, security, convergence, and economy), user features (familiarity and innovativeness), perceived usefulness, trust, satisfaction, and continuance intentions and provides a comparison of Google's Android OS and Apple's iOS. Design/methodology/approach We considered a sample of 245 respondents and used structural equation modeling to analyze the data. Findings The results indicate that convergence and familiarity significantly affected perceived usefulness and that security and economy significantly affected perceived trust in smart banking services. The relationships of security, economy, and innovativeness to perceived usefulness and those of convenience and familiarity to perceived trust were stronger for the Android OS than for iOS. The study contributes by proposing an integrated framework and providing a comparison between the Android OS and iOS in the context of smart banking.

• Journal of the Institute of Electronics Engineers of Korea CI
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• v.46 no.3
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• pp.24-33
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• 2009

Stream data, gathered from ubiquitous sensor networks, change continuously over time. Because they have quite different characteristics from traditional databases, we need new techniques for storing and querying/analyzing these stream data, which are research issues recently emerging. In this research, we implemented a storage manager gathering stream data and storing them into databases, which are sampled continuously from sensor networks. The storage manager cleans faulty data occurred in mobile sensors and it also reduces the size of stream data by merging repeatedly-sampled values into one and by employing the tilted time frame which stores stream data with several different sampling rates. In this research furthermore, we measured the performance of the storage manager in the context of a sensor network monitoring fires of a building. The experimental results reveal that the storage manager reduces significantly the size of storage spaces and it is effective to manage the data stream for real applications monitoring buildings and their fires.