• Journal of the Institute of Electronics Engineers of Korea SD
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• v.43 no.2 s.344
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• pp.60-75
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• 2006

The MPEG-21 Multimedia Framework initiative aims to support a wide range of networks and devices in the delivery and consumption of multimedia resources. One of the primary goals of MPEG-21 is universal multimedia access (UMA) through Digital Item Adaptation (DIA), which supports multimedia streaming to heterogeneous devices ensurung the same readability and seamlessness. We pioneer power saving of luminal devices with MPEG-21 DIA, so that the MPEG-21 DIA can also be used to support power saving, even though the framework is not primarily designed for power reduction and only limited power awareness is defined by DIA. We introduce several power-saving techniques conforming to MPEG-21 DIA specifications and show the dependency relation among introduced techniques. We achieve energy savings of up to $66\%$ in hand-held multimedia devices with minor QoS (quality of service) degradation.

• The KIPS Transactions:PartB
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• v.15B no.2
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• pp.137-146
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• 2008

Fault localization plays a significant role in enormous distributed system because it can identify root cause of observed faults automatically, supporting self-managing which remains an open topic in managing and controlling complex distributed systems to improve system reliability. Although many Artificial Intelligent techniques have been introduced in support of fault localization in recent research especially in increasing complex ubiquitous environment, the provided functions such as diagnosis and prediction are limited. In this paper, we propose fault localization for self-managing in performance evaluation in order to improve system reliability via learning and analyzing real-time streams of system performance events. We use probabilistic reasoning functions based on the basic Bayes' rule to provide effective mechanism for managing and evaluating system performance parameters automatically, and hence the system reliability is improved. Moreover, due to large number of considered factors in diverse and complex fault reasoning domains, we develop an efficient method which extracts relevant parameters having high relationships with observing problems and ranks them orderly. The selected node ordering lists will be used in network modeling, and hence improving learning efficiency. Using the approach enables us to diagnose the most probable causal factor with responsibility for the underlying performance problems and predict system situation to avoid potential abnormities via posting treatments or pretreatments respectively. The experimental application of system performance analysis by using the proposed approach and various estimations on efficiency and accuracy show that the availability of the proposed approach in performance evaluation domain is optimistic.

• KIPS Transactions on Computer and Communication Systems
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• v.2 no.5
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• pp.191-198
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• 2013

It is required to transmit data through shorter path between sensor and base node for real time intrusion detection in wireless sensor networks (WSN) with a mobile base node. Because minimum Wiener index spanning tree (MWST) based routing approach guarantees lower average hop count than that of minimum spanning tree (MST) based routing method in WSN, it is known that MWST based routing is appropriate for real time intrusion detection. However, the minimum Wiener index spanning tree problem which aims to find a spanning tree which has the minimum Wiener index from a given weighted graph was proved to be a NP-hard. And owing to its high dependency on certain nodes, minimum Wiener index tree based routing method has a shorter network lifetime than that of minimum spanning tree based routing method. In this paper, we propose a multi-objective ant colony optimization algorithm to tackle these problems, so that it can be used to detect intrusion in real time in wireless sensor networks with a mobile base node. And we compare the results of our proposed method with MST based routing and MWST based routing in respect to average hop count, network energy consumption and network lifetime by simulation.

• Korean Journal of Remote Sensing
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• v.28 no.1
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• pp.79-93
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• 2012

This paper suggests a system architecture for the advanced meteorological satellite image processing system that is developing by NMSC(National Meteorological Satellite Center). The meteorology satellite image processing system has basically the image acquisition, the image processing, the data management, and the data dissemination functionalities. However, the existing system has some problems with respect to system integration as well as maintenance to accommodate new satellites and/or the new image processing systems for them which will be developed in the near future. To cope with these problems we propose a new system architecture for the advanced meteorology satellite image processing system. To do this we select as the architectural drivers the quality attributes such as modifiability, inter-operability, extendability, reusability, and platform independency and design the architecture to achieve such quality attributes. We expect that the new approach will solve current issues such as system integration, system dependency, or data management problems and will provide easy ways to incorporate new systems and to maintain them.

• Journal of Satellite, Information and Communications
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• v.7 no.3
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• pp.121-129
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• 2012

Any development plan of a Korean space-based navigational system has been neither designed nor introduced yet. However, the demand for the development of a domestic regional satellite navigation system can be originated from the outside of market. The growing dependency on satellite navigational systems in Korea eventually requires the retainment and the operation of a domestic navigational satellite system. There is not many choices on the orbit designs and the system design concepts of a regional augmented navigation satellite system or a regional navigation satellite system for the service on the vicinity of the Korean peninsular. Space situational awareness (SSA) has been a rising issue for both national security and more realistic space business in Korea. Also SSA related technologies in Korea is a newly inaugurated area and is necessary to generate a navigation messages and maintain a future Korean navigation satellite system. In this study, the availability of Japanese Quasi Zenith Satellite System (QZSS) expected to be deployed definitely sooner than Korean counter-part is analyzed. The availability of the similar configured system over Korea is investigated with assumed QZSS type orbit. Also, feasible configuration of orbits for domestic navigation satellite system is suggested. And the observability of a ground-based optical tracking system as a secondary tracking capability is analyzed.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.21 no.8
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• pp.195-204
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• 2020

The purpose of this study was to explore factors associated with smartphone dependence among adults in their 20s. The data were derived from the 2017 Survey on Smartphone Over-dependence conducted by the Ministry of Science and ICT and the National Information Society Agency. There were 3,684 participants. The data were analyzed by frequency, percentage, mean, standard deviation, independent t-test, Pearson's correlation coefficient, and weighted hierarchical multiple regression analysis. For the results, factors related with higher smartphone dependence of participants were duration (β=.18, p=.000) and frequency (β=.04, p=.000) of usage, gaming (β=.15, p=.000), watching videos (β=.09, p=.000), mobile shopping (β=.05, p=.000), working (β=.05, p=.010), e-mailing (β=.13, p=.000), and sports betting (β=.07, p=.000). Music (β=-.07, p=.000) and adult content (β=-.07, p=.000) significantly reduced their smartphone dependence. SNS (Social Networking Services) (β=.01, p=.358) and instant messengers (β=-.02, p=.330) were not factors related to smartphone dependence. However, instant messengers were the most used by participants and had a strong correlation with working (r=.55, p=.000). This study shows that smartphone usage patterns related with smartphone dependence among adults in their 20s are different from those of children and adolescents. These results could be used to more deeply understand smartphone dependence among adults in their 20s and plan early detection and prevention and care of dependence.

• The Journal of the Korea Contents Association
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• v.9 no.10
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• pp.474-481
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• 2009

This study aims to investigate the relation between adult attachment types and communication types of child who attend childhood-care center and their mothers, offer general information of parent education with the importance of language within family as the basic material and provide data and materials to improve communication skills of infants who attend childhood-care center. Based on these goals, study subjects in order to examine the relation between adult attachment types of mothers and communication types of child were established as follows: 1. What is the relation between adult attachment types of mothers and communication types of child? 2. How do attachment types of mothers affect on communication skills of child? The objects of this study were child aged 3 - 5 years old who attend children's house in Daejeon Metropolitan City and their mothers. Measurement tool of adult attachment and tool of communication types of child were used to them for analysis. As the results of the study, there was no correlation between the types of adult attachment and communication types of child. On the contrary, there were passive correlations between dependency and negative communication types and between insecurity and positive communication types. Based on the correlation analysis, insecurity among types of mothers' adult attachment was a major variable that can predict communication skills of children's in the result of multiple regression analysis.

• Journal of KIISE:Software and Applications
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• v.35 no.12
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• pp.716-730
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• 2008

In Service-Oriented Architecture (SOA), service providers develop and deploy reusable services on the repositories, and service consumers utilize blackbox form of services through their interfaces. Services are also highly evolvable and often heterogeneous. Due to these characteristics of the service, it is hard to manage the faults if faults occur on the services. Autonomic Computing (AC) is a way of designing systems which can manage themselves without direct human intervention. Applying the key disciplines of AC to service management is appealing since key technical issues for service management can be effectively resolved by AC. In this paper, we present a theoretical model, Symptom-Cause-Actuator (SCA), to enable autonomous service fault management in SOA. We derive SCA model from our rigorous observation on how physicians treat patients. In this paper, we first define a five-phase computing model and meta-model of SCA. And, we define a schema of SCA profile, which contains instances of symptoms, causes, actuators and their dependency values in a machine readable form. Then, we present detailed algorithms for the five phases that are used to manage faults the services. To show the applicability of our approach, we demonstrate the result of our case study for the domain of 'Flight Ticket Management Services'.

• Journal of Global Scholars of Marketing Science
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• v.17 no.4
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• pp.201-221
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• 2007

Recently price as an information clue on online shopping has become important and price dependency has been also increased. This study suggests the flow which customers experience on online shopping plays a leading role in a matter of revisiting intention, but price sensitivity has a possibility to decrease the flow on the basis of literature investigation. While telling the differences in types of shopping malls, this study also examines relationship verifications with price sensitivity, flow of internet shopping mall and revisiting intension. The results show the flow experience through temporal dissociation makes increase a revisiting intention. To the contrary, this study presents a price search dimension in price sensitivity has negative influence to each dimension of temporal dissociation, heightened enjoyment and curiosity and also the relationship between price importance and flow is rejected. In addition, this influence gets different results by internet auction, pure internet shopping mall, shopping mall which can show price comparisons. In the case of shopping mall which can show price comparisons, more price researches become less curiosities and more heightened enjoyments and curiosities get more revisiting intentions. In the internet auction's case, price search decreases a temporal dissociation and heightened enjoyment and improves a revisiting intention when a temporal dissociation and heightened enjoyment are increased. Price research reduces three types of flow dimensions such as a temporal dissociation, heightened enjoyment, and curiosity in the pure internet shopping mall. In addition, only heightened enjoyment affects to a revisiting intentions.

• Journal of Internet Computing and Services
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• v.21 no.1
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• pp.179-190
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• 2020

In the Unix-like system environment, the GOT overwrite attack is one of the traditional control flow hijacking techniques for exploiting software privileges. Several techniques have been proposed to defend against the GOT overwrite attack, and among them, the Full Relro(Relocation Read only) technique, which blocks GOT overwrites at runtime by arranging the GOT section as read-only in the program startup, has been known as the most effective defense technique. However, it entails loading delay, which limits its application to a program sensitive to startup performance, and it is not currently applied to the library due to problems including a chain loading delay problem caused by nested library dependency. Also, many compilers, including LLVM, do not apply the Full Relro technique by default, so runtime programs are still vulnerable to GOT attacks. In this paper, we propose a GOT protection scheme using the Control Flow Integrity(CFI) technique, which is currently recognized as the most suitable technique for defense against code reuse attacks. We implemented this scheme based on LLVM and applied it to the binutils-gdb program group to evaluate security, performance and compatibility. The GOT protection scheme with CFI is difficult to bypass, fast, and compatible with existing library programs.