• Journal of Digital Contents Society
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• v.13 no.4
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• pp.625-629
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• 2012

This paper is presented to prepare NGN quality assurance management process under the quality system test methodology. The process should be drawn for NGN quality measurement framework of multimedia traffic. NGN test bed management process model are QoS measurement metrics, measurement interval meter above, and measuring tools, measuring equipment, measurement methods and measurement results from a series of processes for the analysis and methodology. This model, NGN quality assurance activities should be utilized in the future. Quality target level only when themselves constantly measured and managed, does not guarantee the communication quality of service. It is sensitive to the importance of NGN network technology paradigm for research on quality management in the NGN.

• Journal of Environmental Science International
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• v.20 no.1
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• pp.81-91
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• 2011

Air quality monitoring networks are very important facilities to manage urban air pollution control and to set up an environmental policy. Since air quality monitoring network of Daegu was allocated from 1980s to mid-90s, there is need to reevaluate it and relocated its site. This study was evaluated the position of Daegu air quality monitoring station by unit environmental sensitivity index, grid emission rate, CAI (Comprehensive Air-quality Index) point. The investigation domain covered an area of 16 $\times$ 24 km centered at the metropolitan area of Daegu with grid spacing of 2 km. The location of alternative air quality monitoring networks was selected through optimization and quintiles analysis of total score. The result showed that all things considered, new air quality monitoring network need to install grid numbers 10, 28, 36, 37, 46. We also recommand three scenarios of alternative air quality monitoring network when considering unit environmental sensitivity index, emission rate and CAI point.

• Journal of information and communication convergence engineering
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• v.13 no.1
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• pp.7-14
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• 2015

In a multi-hop wireless network, connectivity is determined by the link that is established by the receiving signal strength computed by subtracting the path loss from the transmission power. Two path loss models are commonly used in research, namely two-ray ground and shadow fading, which determine the receiving signal strength and affect the link quality. Link quality is one of the key factors that affect network performance. In general, network performance improves with better link quality in a wireless network. In this study, we measure the network connectivity and performance in a shadow fading path loss model, and our observation shows that both are severely degraded in this path loss model. To improve network performance, we propose power control schemes utilizing link quality to identify the set of nodes required to adjust the transmission power in order to improve the network throughput in both homogeneous and heterogeneous multi-hop wireless networks. Numerical studies to evaluate the proposed schemes are presented and compared.

• The Journal of Information Systems
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• v.24 no.1
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• pp.67-94
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• 2015

Recently, the popularity of Social Network Service (SNS) along with the spread of smart phone, personal computer and tablet PC helps personal network to construct new forms of services in cyberspace. As such, SNS plays a significant role in constructing diverse online networks and there is a growing interest on SNS at societal level. In this vein, the purpose of the research was to find the factors affecting the continuance intention to use social network services. The major findings are summarized as follows. First, "System Quality", "Contents Quality", "Personal Innovativeness", "Self-Efficiency", "Honor Benefit" has significant effects on "Relationship Quality". Yet, "Economic Benefit" is not statistically significant on "Relationship Quality". Second, "Relationship Quality" has a significant effect on "Continuous Usage Intention". Last, our research discovered the relationship between exogenous variables which would serve as valuable inputs in the development of strategic guideline and plan for SNS companies and related services.

• The Journal of Information Systems
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• v.21 no.4
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• pp.133-153
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• 2012

This study explores the factors influencing user satisfaction of mobile IPTV and their relationship. We formulate the research model based on characteristics of mobile device and IPTV. Responsiveness, contents satisfaction, price satisfaction, aesthetic simplicity, network quality are proposed as essential antecedents of mobile IPTV satisfaction. We also suggest network quality and gender as moderators. Our data analysis with 297 mobile IPTV users shows contents and price have significant positive effect on mobile IPTV satisfaction. Network quality shows positive moderation effect on the relationship between responsiveness and satisfaction.

• Journal of the Korean Home Economics Association
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• v.45 no.5
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• pp.75-83
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• 2007

The purpose of this study was to investigate the relationships between peer victimization by peers, bullying, and friendships, with a focus on friendship network, friendship quality, and friends' characteristics. The subjects were 678 fifth and sixth grade primary school children recruited from a public school in Bucheon city. The peer nomination index was used to assess peer victimization, bullying, and friendship network. In addition, children themselves reported on the quality of their friendships using the Friendship Quality Scale. The results showed that victimization by peers was influenced by friendship network size, support, and victimization of friends, whereas bullying was explained by support and the bullying behaviors of friends.

• Journal of the Korean Society for Precision Engineering
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• v.14 no.1
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• pp.101-107
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• 1997

Recently, as the raw water quality becomes to be polluted and the seasonal and local variation of water quality becomes to be severe, an exact control of coagulant dosing have been required in the water treat- ment plant. The amounts of coagulant is related to the raw water quality such as turbidity, alkalinity, water temperature, pH and edectrical conductivity. However the process of chemical reaction has not been clarified so far, so the dosing rate has been decided by jar-test, which is taken one or two hours. For the sake of this coagulant dosing control, fuzzy neural network to fuse fuzzy logic and neural network was proposed, and the scheme was applied to automatic determination of coagulant dosing rate. This controller can automatically identify the if-then rules and tune the membership functions by utilizing expert's cintrol data. It is shown that determination of coagulant dosing rate according to real time sensing of water quality is very effect.

• Journal of the Optical Society of Korea
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• v.19 no.4
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• pp.340-345
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• 2015

The Internet traffic is forecasted to grow at a compound annual rate of 21 % from 2013 to 2018, according to surveys carried out by Cisco [1]. Network resources are significantly over-provisioned in today's networks, and it is quite common to see link utilization in the 30-40% range [2]. Additionally, the multi-media services have widely divergent bandwidth and Quality of Experience (QoE) requirements. Unfortunately, the huge transmission capacity will increase the power consumption of network equipment [3]. Applications Coordinated with Transport, Internet Protocol and Optical Networks (ACTION) [4] has been proposed to realize a multi-QoE, application-centric, and highly energy-efficient network that leverages flexible elastic optical network technologies [5-7]. This paper provides key network technologies for realizing the ACTION, which are a virtual optical slice core network and a Time Division Multiplexing (TDM)-based deterministic active optical access network.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.10 no.12
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• pp.2166-2172
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• 2006

This paper presents a quality-of-service-enabled next generation local area network architecture which can provide efficiently convergence services over the Internet protocol. The basic concept of the architecture is to combine such three principle technologies as programmable switched network quality-of-service resource management and Internet protocol based network convergence. We discuss system entities and technologies development, which constitute the proposed network. The architecture of the network is then described. Implementation of systems verifies the proposed technologies. The network as a next generation local area network can provide quality-of-service-enabled real-time communication services as well as existing data traffic, and the open programmable interface can facilitates to adopt cost-effectively emerging new services or functionalities.

• Journal of Environmental Impact Assessment
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• v.30 no.2
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• pp.75-88
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• 2021

Six locations in the automated monitoring network at the Geum River Basin were selected forthis study. The water quality characteristics at two of the locations in the water quality monitoring network that were identical, or nearby, were examined, and their correlations were evaluated through statistical analysis. The results of the water quality analysis were converted to the water quality index and expressed in grades for comparison. For the data necessary for the study, public data from four years, from 2016-2019 were used and the evaluation parameters were water temperature, pH, EC, DO, TOC, TN, and TP. Results of the analysis showed that the water quality concentrations measured in the automated monitoring network and the water quality monitoring network differed in some measured values, but they tended to register variation in a specified ratio in most of the locations in the network. The analysis of the correlations of the parameters between the two monitoring networks found that water temperature, EC, and DO showed high correlations between the two monitoring networks. The TOC, TN, and TP showed high correlations, with a 0.7 or higher (correlation coefficient r), with the exception of some of the monitoring networks, although their correlations were lower than those of the basic parameters. The water quality index analysis showed that the water quality index values of the automated monitoring network and the water quality monitoring network were similar. The water quality index decreased and the pollution degree increased in the downstream direction, in both networks.