• The Journal of the Institute of Internet, Broadcasting and Communication
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• v.16 no.3
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• pp.1-6
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• 2016

As IPTV has become one of the major Internet services, IPTV users and channels increase rapidly. However, the increased number of channels makes users difficult to find their desired channels. Along with this, the channel switching time of IPTV incurs serious user-perceived delay. To alleviate these problems, this paper presents hybrid schemes that combine channel prefetching and reordering schemes. Simulation experiments show that combining adjacency based prefetching and popular channel reordering reduces the channel seek time by up to 44.7% in comparison with the conventional channel seeking interfaces.

• Journal of the Korean Society for Geothermal and Hydrothermal Energy
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• v.9 no.1
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• pp.1-7
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• 2013

With the architectural energy saving technique such as building insulation, airtightness etc., changing the indoor temperature and shortening the air conditioning time etc. are the good methods to practice energy saving in our lives. This study aims to seek a way to realize energy saving under investigation through a questionnaire survey about energy consumption condition and energy saving perception. 93% of the respondents recognized the need for energy saving, and 67% said more energy saving would possible in homes. Viable energy saving way was questioned by five steps method. More than 50% responded 'possible' or 'seems possible' at most of the items. Whereas less than 50% responded 'possible' or 'seems possible' at the items of 'lessening the cooling time' and 'lessening the shower time'. Ages of 50s who responded 'possible' or 'seems possible' was relatively less compared to 30s and 40s.

• KSII Transactions on Internet and Information Systems (TIIS)
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• v.10 no.7
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• pp.3150-3170
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• 2016

In Intelligent Transportation Systems (ITS), logistics distribution and mobile e-commerce, the real-time, accurate and reliable vehicle trajectory prediction has significant application value. Vehicle trajectory prediction can not only provide accurate location-based services, but also can monitor and predict traffic situation in advance, and then further recommend the optimal route for users. In this paper, firstly, we mine the double layers of hidden states of vehicle historical trajectories, and then determine the parameters of HMM (hidden Markov model) by historical data. Secondly, we adopt Viterbi algorithm to seek the double layers hidden states sequences corresponding to the just driven trajectory. Finally, we propose a new algorithm (DHMTP) for vehicle trajectory prediction based on the hidden Markov model of double layers hidden states, and predict the nearest neighbor unit of location information of the next k stages. The experimental results demonstrate that the prediction accuracy of the proposed algorithm is increased by 18.3% compared with TPMO algorithm and increased by 23.1% compared with Naive algorithm in aspect of predicting the next k phases' trajectories, especially when traffic flow is greater, such as this time from weekday morning to evening. Moreover, the time performance of DHMTP algorithm is also clearly improved compared with TPMO algorithm.

• Journal of Arbitration Studies
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• v.14 no.1
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• pp.61-101
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• 2004

Information and communications technologies are affecting an economic and social transformation of all countries. Without exception international commercial dispute resolution systems are faced with change its mechanism to online technology. Dispute parties can seek redress through arbitration other than litigation or mediation. Traditional dispute resolutions do not match the cyber trade environment which is basically pursuit the speed and efficiency in cyberspace. Arbitration other than resolution methods have been considered to be match with the online environment which is including party autonomy, speed and internationally accepted and binding awards. Traditional arbitration, however is lack of time and different physical location relating all parties. So we now think cyberspace as for the resolving place which is online arbitration. Even the parties exist in different space and time they may meet in the same time and space without moving or trips. Nowadays there are many online arbitration service provider serving the resolution of dispute arising with online transaction. In this paper we study the tendency for online arbitration, the recognize uncertain matters and avoiding programs its matters when use the online arbitration between disputing parties under cyber trade environment.

• Structural Engineering and Mechanics
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• v.66 no.1
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• pp.139-149
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• 2018

Many practical engineering problems are associated with nonlinear systems subjected to nonstationary random excitations. Equivalent linearization methods are commonly used to seek for approximate solutions to this kind of problems. Compared to various approaches developed in the frequency and mixed time-frequency domains, though directly solving the system equation of motion in the time domain would improve computation efficiency, only limited studies are available. Considering the fact that the orthogonal functions have been widely used to effectively improve the accuracy of the approximated responses and reduce the computational cost in various engineering applications, an orthogonal-function-based equivalent linearization method in the time domain has been proposed in the current paper for nonlinear systems subjected to nonstationary random excitations. In the numerical examples, the proposed approach is applied to a SDOF system with a set-up spring and a SDOF Duffing oscillator subjected to stationary and nonstationary excitations. In addition, its applicability to nonlinear MDOF systems is examined by a 3DOF Duffing system subjected to nonstationary excitation. Results show that the proposed method can accurately predict the nonlinear system response and the formulation of the proposed approach allows it to be capable of handling any general type of nonstationary random excitations, such as the seismic load.

• Journal of Environmental Health Sciences
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• v.31 no.2 s.83
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• pp.152-159
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• 2005

Laboratory scale experiments were conducted to study the applicability, and to compare the performance of two types of sequencing batch reactor (SBR)systems, a conventional SBR and sequencing batch biofilm reactor (SBBR) on the biological nitrogen and phosphorus removal. The nitrification rate in SaR was higher than that in SBBR both in high influent TOC concentration. The denitrification was completed at the first non-aeration period in SBR, however, the additional non-aeration period should be installed or the first aeration period should be extended more in order to complete the nitrogen removal in SBBR. The time at the first aeration period was more needed as about 4-5 h in order to uptake all the released $PO_4^{3-}\;-P$ at the first non-aeration period. SBBR needed more operation time, especially the first aeration time, than SBR at the high influent TOC concentration in order to complete nitrogen and phosphorus removal.

• Journal of Korean Society for Quality Management
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• v.42 no.1
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• pp.71-79
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• 2014

Purpose: The purpose of this study is to develop the methods for evaluating patients' queue environment using decision tree and queueing theory. Methods: This study uses CHAID decision tree and M/G/1 queueing theory to estimate pain point and patients waiting time for medical service. This study translates hospital physical data process to logical process to adapt queueing theory. Results: This study indicates that three nodes of the system has predictable problem with patients waiting time and can be improved by relocating patients to other nodes. Conclusion: This study finds out three seek points of the hospital through decision tree analysis and substitution nodes through the queueing theory. Revealing the hospital patients' queue environment, this study has several limitations such as lack of various case and factors.

• Journal of Communications and Networks
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• v.15 no.5
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• pp.504-513
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• 2013

Communication in delay tolerant networks (DTNs) relies on message transport by mobile nodes, and a correct understanding of the node mobility characteristics is therefore crucial to the design of an efficient DTN routing protocol. However, previous work has mainly focused on uncovering all behaviors of node movement, which is not conducive to accurately detecting the specific movement characteristics of a different node. In this paper, we seek to address this problem based on a consideration of social relationships. We first consider social ties from both static and dynamic perspectives. For a static perspective, in addition to certain accidental events, social relations are considered for a long time granularity and tend to be stable over time. For a dynamic perspective, social relations are analyzed in a relatively short time granularity and are likely to change over time. Based on these perspectives, we adopted different efficient approaches to dividing node pairs into two classes, i.e., familiar and unfamiliar pairs. A threshold approach is used for static social ties whereas a density-based aggregation method is used for dynamic social relationships. Extensive experimental results show that both familiar and unfamiliar node pairs have the same inter-contact time distribution, which closely follows a power-law decay up to a certain point, beyond which it begins to exponentially decay. The results also demonstrate that the inter-contact time distribution of familiar pairs decays faster than that of unfamiliar pairs, whether from a static or dynamic perspective. In addition, we also analyze the reason for the difference between the inter-contact time distributions of both unfamiliar and familiar pairs.

• Korean Journal of Adult Nursing
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• v.22 no.5
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• pp.537-551
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• 2010

Purpose: This study was designed to identify meaningful themes related to the recognition of lifestyle risk factors and barriers in seeking treatment following an acute event of first-time acute myocardial infarction. Methods: A methodological mixed method of thematic content analysis and a quantitative analysis was used. The sample consisted of 120 male patients < 65 years of age who agreed to be in the study were interviewed using a semistructured during 2008-2009. Data were analyzed according to the procedure of thematic content analysis and the meaningful themes were coded into SPSS data for quantitative analysis. Results: Pre-hospital delay greater than three hours reported by 58.3% (n=70) of the sample and similarly 63.3% had no recognition about their symptoms as cardiac in origin. The mean number of risk factors was $3.9{\pm}1.8$ out of 11 when lifestyle and psychosocial factors were included. From the interview data among the 70 patients delayed greater than three hours, thirty-five themes categorized into 12 main themes influenced the delayed decision which was identified according to personal-cognitive, socio-cultural, and contextual factors. Conclusion: Health care providers should consider these themes in designing individual interventions to make lifestyle changes and to facilitate more prompt decisions to seek care.

• The Journal of Society for e-Business Studies
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• v.14 no.1
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• pp.143-160
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• 2009

In determining the performance of OLAP database applications, the structure and the effective access methods to the underlying disk system is a significant factor. In recent years, hard disks are designed with multiple physical zones where seek times and data transfer rates vary across the zones. However, there is little consideration of multi-zone disks in previous works. Instead, they assumed a traditional disk model that comes with many simplifying assumptions such as an average seek-time and a single data transfer rate. In this paper, we propose a technique storing a set of materialized views into the multi-zoned disks in OLAP environment dealing with large sets of data. We first present the disk zoning algorithm of materialized views according to the access probabilities of each views. Also, we address the problem of storing views in the dynamic environment where data are updated continuously. Finally, through experiments, we prove the performance improvement of the proposed algorithm against the conventional methods.