• Journal of Positioning, Navigation, and Timing
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• v.4 no.2
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• pp.43-55
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• 2015

In the case of satellite navigation positioning, the shielding of satellite signals is determined by the environment of the region at which a user is located, and the navigation performance is determined accordingly. The accuracy of user position determination varies depending on the dilution of precision (DOP) which is a measuring index for the geometric characteristics of visible satellites; and if the minimum visible satellites are not secured, position determination is impossible. Currently, the GLObal NAvigation Satellite system (GLONASS) of Russia is used to supplement the navigation performance of the Global Positioning System (GPS) in regions where GPS cannot be used. In addition, the European Satellite Navigation System (Galileo) of the European Union, the Chinese Satellite Navigation System (BeiDou) of China, the Quasi-Zenith Satellite System (QZSS) of Japan, and the Indian Regional Navigation Satellite System (IRNSS) of India are aimed to achieve the full operational capability (FOC) operation of the navigation system. Thus, the number of satellites available for navigation would rapidly increase, particularly in the Asian region; and when integrated navigation is performed, the improvement of navigation performance is expected to be much larger than that in other regions. To secure a stable and prompt position solution, GPS-GLONASS integrated navigation is generally performed at present. However, as available satellite navigation systems have been diversified, finding the minimum satellite constellation combination to obtain the best navigation performance has recently become an issue. For this purpose, it is necessary to examine and predict the navigation performance that could be obtained by the addition of the third satellite navigation system in addition to GPS-GLONASS. In this study, the current status of the integrated navigation performance for various satellite constellation combinations was analyzed based on 2014, and the navigation performance in 2020 was predicted based on the FOC plan of the satellite navigation system for each country. For this prediction, the orbital elements and nominal almanac data of satellite navigation systems that can be observed in the Korean Peninsula were organized, and the minimum elevation angle expecting signal shielding was established based on Matlab and the performance was predicted in terms of DOP. In the case of integrated navigation, a time offset determination algorithm needs to be considered in order to estimate the clock error between navigation systems, and it was analyzed using two kinds of methods: a satellite navigation message based estimation method and a receiver based method where a user directly performs estimation. This simulation is expected to be used as an index for the establishment of the minimum satellite constellation for obtaining the best navigation performance.

• KIPS Transactions on Software and Data Engineering
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• v.7 no.8
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• pp.297-306
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• 2018

In this paper, we address how to apply Apache Storm, a distributed stream processing framework, to InfiniBand, a high performance communication device. An easy way to run Storm on InfiniBand is to simply use IPoIP (IP over InfiniBand). However, this method causes a serious CPU load on the node, which is caused by frequent context switches and buffer copies. To solve this problem, we propose a new communication method using InfiniBand's Remote Direct Memory Access (RDMA) function in Storm. First, we design and implement RJ-Netty (RDMA/JXIO Netty), a new framework that replaces Netty, the legacy framework, to exploit RDMA functionality. Second, we reimplement the related classes so that Storm can use both existing Netty and new RJ-Netty. Third, we extend the JXIO server functionality so as to support multi-threading to maximize the performance of RJ-Netty. Experimental results show that the proposed RJ-Netty significantly reduces CPU load while improving message throughput compared to IPoIB as well as Ethernet. This paper is the first attempt to run Apache Storm on InfiniBand, and we believe that it is an excellent research result that improves the performance of Storm by using InfiniBand RDMA.

• Korean journal of communication and information
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• v.35
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• pp.362-393
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• 2006

The purpose of this manuscript was to investigate the effects of issue involvement and relation of perceivers to comparison targets on the magnitude of third person perceptions. The investigation was expected to help us to understand the underlying process of third person effect hypothesis. Data was collected from adult residents in Ohio, United States by telephone survey in 2003(n=524). Like most other third person effect studies, this study supported the hypothesis: Respondents perceived more media effects on others than themselves for both 'Negative media portrayals of smokers' and 'News coverage of Roman Catholic priest's sexual scandals'. Results of five hypothesis tests suggest that when relationship between a perceiver and a particular comparison target is present third person perception is explained more by cognitive components than motivational components. In this case, third person perception varies with comparison target's issue involvement while it is independent of social distance between the perceivers and the comparison target. Also, perceivers' issue involvement positively correlates with the magnitude of third person effect. Based on the results, it is concluded that when perceives or a comparison target is involved in a message cognitive processes accounting for the relationship can impact the magnitude of third person effect. An important theoretical implication of the study is that third person effect is, to some extent, related with framing effect and priming effect.

• Journal of Global Scholars of Marketing Science
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• v.12
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• pp.99-119
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• 2003

A model is proposed for the role of emotional intensity of a web site, and the moderating influence of product involvement, in the Integrative Framework of persuasion (Meyers-Levy and Malvaiya 1999). The model also appropriately operationalizes the constructs emotional intensity of a web site and product involvement The three routes to persuasion, Central, Peripheral, and Experiential correspond to high, moderate, and low involvement (Meyers-Levy and Malaviya 1999). The involvement construct is measured from message recipients using the Personal Product Inventory (Pill, which was developed to capture the concept of product involvement (Zaichkowsky 1985). The conceptualization of the Personal Product Inventory is a contextrree measure that also has robust psychometric properties when applied to advertisements (Zaichkowsky 1994). The propositions highlight the expected importance of emotional intensity of a web site. The moderating influence of product involvement is also proposed. Specifically, what this work proposes is that the emotional intensity of a product site has a larger impact on attitude change under low product involvement, as opposed to moderate product involvement. Support for this reasoning can be found in the persuasion literature (Petty et al 1986). The Petty et al (1986) frame work is a dual process descriptive and predictive frame work in the area of altitude formation and change. Recently, Myers Levy and Malaviya (1999) have proposed a tri-process framework. This is in tum based on the dual process model of Petty et al. (1986). The study outlined in this paper aims to deepen the Meyers Levy and Malaviya (1999) and frame work. The propositions outlined in the model are empirically tested using a repeated measures experimental design. The emotional intensity is measured using a scale that is based on experts judgments. Using a paired comparison t-test two sites are determined to be of high and low emotional intensity. The model is tested using a repeated measures experimental design. The first independent variable Emotional Intensity of the site is manipulated. The Second independent variable, Personal Product Inventory is measured. While, the dependent variable, product altitude change will also be measured. Utilizing Analysis of Variance (ANOVA) the data is analyzed using SPSS. The results suggest that besides the rational content of messages their emotional content can also influence attitude change. Specifically, it is proposed that the manipulation of emotional intensity of a product Web site has a greater impact on product altitudes under high and low product involvement conditions, rather than moderate product involvement. However, the results for product involvement as a continuous variable has a p value of 0.09. Further, the results for three levels of product involvement were far from significant. For two levels of product involvement also, the results were insignificant, the p value approached 0.20. This evidence indicates that it is premature to conclude that there are three routes to persuasion. A caveat, however, must be added, in that the manipulations may not have been strong enough to test the proposed hypotheses. Further, undoubtedly, there is unequivocal evidence the emotional intensity of a product Web site, as measured here, has a direct impact on product attitudes.

• Journal of Korea Multimedia Society
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• v.14 no.1
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• pp.33-43
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• 2011

Routing technologies considering QoS-based hypermedia services have been seen as a crucial network property in next generation optical Internet (NGOI) networks based on IP/dense-wavelength division multiplexing (DWDM). The huge potential capacity of one single fiber. which is in Tb/s range, can be exploited by applying DWDM technology which transfers multiple data streams (classified and aggregated IP traffics) on multiple wavelengths (classified with QoS-based) simultaneously. So, DWDM-based optical networks have been a favorable approach for the next generation optical backbone networks. Finding a qualified path meeting the multiple constraints is a multi-constraint optimization problem, which has been proven to be NP-complete and cannot be solved by a simple algorithm. The majority of previous works in DWDM networks has viewed heuristic QoS routing algorithms (as an extension of the current Internet routing paradigm) which are very complex and cause the operational and implementation overheads. This aspect will be more pronounced when the network is unstable or when the size of network is large. In this paper, we propose a flooding-based unicast and multicast QoS routing methodologies(YS-QUR and YS-QMR) which incur much lower message overhead yet yields a good connection establishment success rate. The simulation results demonstrate that the YS-QUR and YS-QMR algorithms are superior to the previous routing algorithms.

• Journal of KIISE:Software and Applications
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• v.31 no.8
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• pp.1092-1100
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• 2004

An E-mails have regarded as one of the most popular methods for exchanging information because of easy usage and low cost. Meanwhile, exponentially growing unwanted mails in user's mailbox have been raised as main problem. Recognizing this issue, Korean government established a law in order to prevent e-mail abuse. In this paper we suggest hybrid spam mail filtering system using weighted Bayesian classifier which is extended from naive Bayesian classifier by adding the concept of preprocessing and intelligent agents. This system can classify spam mails automatically by using training data without manual definition of message rules. Particularly, we improved filtering efficiency by imposing weight on some character by feature extraction from spam mails. Finally, we show efficiency comparison among four cases - naive Bayesian, weighting on e-mail header, weighting on HTML tags, weighting on hyperlinks and combining all of four cases. As compared with naive Bayesian classifier, the proposed system obtained 5.7% decreased precision, while the recall and F-measure of this system increased by 33.3% and 31.2%, respectively.

• Journal of the Korean Society for information Management
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• v.30 no.2
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• pp.269-295
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• 2013

This study purported to study the uses of information and communication technology (ICT) tools in their daily life among the undergraduate and graduate students majoring science and engineering. It also examined the purposes of the uses of the major ICT tools, the differences in their information technology uses between graduate and undergraduate students. The data were collected from 83 undergraduate and graduate students from four universities using content analysis of an observational logs and a survey questionnaire. The observational logs were collected using an instant message application available on a smart phone. Study results revealed desktop computers, laptop computers, and smart phones as the three most heavily used ICT tools among the participants and typical situations students use each of the three tools. There were also sharp distinctions between graduate and undergraduate students in their selection of the tools, and distinctions between work and non-work situations. The findings of this study can be used to redesign information services and systems for the scientists and engineers in the next generation.

• The Journal of the Korea Contents Association
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• v.9 no.8
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• pp.360-366
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• 2009

The purpose of this research was to study of the lower body obesity control with female university students, particularly has been done meridian message and aroma therapy, The data included in the remainder of this research was gathered from the experimental groups consisted of eighteen female students for tested group and compared group over 8 weeks. By the observation of tested group and compared group, we could see the measurement of thigh and calf sizing down overall, but they still show some differences depend on physical constitutions of each members who has been tested. This meant that the result could be changed by the will and persistent endurance of experimented ones Both of tested group and compared group's body mass index shrinked but still there were some exceptions, this result showed the difference of each participants' willingness as well as the age gap. We could find the reduction of Total Cholesterol, LDL, neutral fat and blood sugar in both tested group and compared group. However in case of HDL the measurement increased which means wrong method of controlling obesity can show some abnormal figures

• Journal of the Korea Academia-Industrial cooperation Society
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• v.11 no.8
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• pp.2780-2792
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• 2010

In this study, we examine what components of e-learning environment affect e-learners' satisfaction. We focus on the task based approach to perceived website complexity(PWC). We study about the role of e-tutor using the internet, telephone, text message and e-mail etc. To test our model, we collected 235 data from online learners of Korea Culture & Content Agency using survey method. The research was conducted by SPSS15.0. Our results show that the relationship between PWC and e-learner satisfaction was negative. The rules of e-tutor are supporting e-learning service and facilitating recommendation intention. This study provides implications to design future e-learning service, understand user's herd behavior and evaluate learning process developed.

• Journal of KIISE:Databases
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• v.34 no.6
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• pp.528-545
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• 2007

Recently ontology has been an attractive technology along with the business strategy of providing a plenty of more intelligent services. The essential problem in application domains using ontology is that all members, agents, and application programs in the domains must share the same ontology concepts. However, a variety of mobile devices, sensing devices, and network components manufactured by various companies, a variety of common carriers, and a variety of contents providers make multiple heterogeneous ontologies more likely to coexist. We can see many past researches fallen into resolving this semantic interoperability. Such methods can be broadly classified into by-mapping, by-merging, and by-translation. In this research, we focus on by-translation among them which uses a translation rule directly made between two heterogeneous ontology data like OntoMorph. However, the manual composition of the direct translation rule is not convenient by itself and if there are N ontologies, the direct method has the rule composition complexity of $O(N^2)$ in the worst case. Therefore, in this paper we introduce the cascade composition of translation rules based on web openness in order to improve the complexity. The research result made us recognize some important factors in an ontology translation system, that is speediness of translation, and conveniency of translation rule composition, and some experiments and comparing analysis with existing methods showed that our cascade method has more conveniency with insuring the speediness and the correctness.