• Journal of the Korea Society of Computer and Information
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• v.15 no.3
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• pp.73-80
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• 2010

The advancement of communication and networking technologies has enabled e-science and commercial application that often require the transport of large volume of data over wide-area network. Schedulable high-bandwidth low-latency connectivity is required to transport the large volume of data. But the public Internet does not provide predictable service performance. Especially, if data providers and users are far away, dedicated bandwidth channels are needed to support remote process efficiently. Currently several network research projects are in progress to develop dedicated connectionsy sA bandwidth scheduler computes an user requested path based on network topology information and link bandwidth allocationsy In this paper, we have proposed an efficient algorithm for finding the earliest time interval when minimum bandwidth and duration are giveny Our algorithm is experimentally compared with the known algorithm.

• Journal of KIISE:Computer Systems and Theory
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• v.28 no.12
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• pp.674-684
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• 2001

This paper presents the SIC(Size-Interval-Count) prefetching scheme that can record the file access patterns of applications within a relatively small space of memory based on the repetitiveness of the file access patterns. Several knowledge-based prefetching methods were recently introduced, which includes high correctness in predicting future accesses of applications. They records the access patterns of applications and uses recorded access pattern information to predict which blocks will be requested next. Yet, these methods require to much memory space. Accordingly, the proposed method then uses the recorded file access patterns, referred to as "SIC access pattern information", to correctly predict the future accesses of the applications. The proposed prefetching method improved the response time by about 40% compared to the general file system and showed remarkable memory efficiency compared to the previously knowledge-based prefetching methods.

• Journal of the Korean Institute of Rural Architecture
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• v.20 no.1
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• pp.45-52
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• 2018

The purpose of this study is to investigate safety and dangerous awareness of environment on walking trails. For this purpose, questionnaire survey are carried out by people who had experience using walking trails during 2016. It is evaluated that environments of walking trails located inside big cities are inferior than ones located in small and medium-sized cities and countryside in air pollution, bed smell, water pollution, noise, and waste. Needs about management and number installed public restroom are high for hygienic environment of walking trails. With waste treatment, users of 2.4 percentage are showed improper behavior that they left their rubbish at the place out of view but others bring their trash. Accident likelihood is highly appreciated and possibility of physical accident like slipping is showed at the highest. The reasons of accident on walking trails are responded with carelessness of walkers and improper of installation or management of safety facility at the most. For safety environment of walking trails, needs of installation of safety fences and notices of dangerous area are requested. In order to separate prevention from paths of walking trails, signposts are needed at visual clearness, maintenance, installation with proper interval and location, and correct contents. Respondents of 2.4 percentage have experiences of accident on walking trails and physical accident like slipping is occurred at the most.

• Proceedings of the Korean Institute of Intelligent Systems Conference
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• 1998.10a
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• pp.173-179
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• 1998

This paper proposes a new call admission control scheme utilizing an inverse fuzzy vector quantizer(IFVQ) and neural net, which combines benefits of IFVQ and flexibilities of FCM(Fuzzy-C-Menas) arithmatics, to decide whether a requested call that is not trained in learning phase to be connected or not. The system generates the estimated traffic pattern of the cell stream of a new call, using feasible/infeasible patterns in codebook, fuzzy membership values that represent the degree to which each pattern of codebook matches input pattern, and FCM arithmatics. The input to the NN is the vector consisted of traffic parameters which is the means and variances of the number of cells arriving inthe interval. After training(using error back propagation algorithm), when the NN is used for decision making, the decision as to whether to accept or reject a new call depends on whether the output is greater or less then decision threshold(+0.5). This method is a new technique for call admi sion control using the membership values as traffic parameter which declared to CAC at the call set up stage, and is valid for a very general traffic model in which the calls of a stream can belong to an unlimited number of traffic classes. Through the simmulation. it is founded the performance of the suggested method outforms compared to the conventional NN method.

• Journal of KIISE:Databases
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• v.30 no.4
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• pp.372-380
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• 2003

Temporal databases support time-varying events so that conventional aggregate functions are extended to be processed with time for temporal aggregate functions. In the previous approach, it is done repeatedly to find time intervals and is calculated the result of each interval whenever target events are different. This paper proposes a method which processes temporal aggregate function queries using time point sequence. We can make time point sequence storing the start time and the end time of events in temporal databases in advance. It is also needed to update time point sequence due to insertion or deletion of events in temporal databases. Because time point sequence maintains the information of time intervals, it is more efficient than the previous approach when temporal aggregate function queries are continuously requested, which have different target events.

• Safety and Health at Work
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• v.13 no.4
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• pp.507-511
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• 2022

Law enforcement officers (LEOs) often encounter rapidly changing and uncontrolled situations that expose them to various hazards. A law enforcement agency requested an evaluation by the National Institute for Occupational Safety and Health (NIOSH) when multiple LEOs reported illness after executing a search warrant and taking a suspect into custody. NIOSH investigators interviewed LEOs and reviewed medical records, forensic laboratory results for collected evidence, and environmental testing results of samples taken after the operation. Two-thirds (25 of 38) of LEOs who participated in the operation reported ≥1 symptom. Eleven LEOs met a case definition for influenza-like illness (ILI). Members of one unit were more likely to have ILI than non-members (prevalence ratio (PR), 4.1; 95% confidence interval (CI): 1.3-13.0; p = 0.01). Influenza vaccination was associated with a lower prevalence of ILI (PR, 0.2; 95% CI, 0.1-0.9; p = 0.02). Preventing employees from working while ill and annual influenza vaccination might prevent similar occurrences.

• The Transactions of The Korean Institute of Electrical Engineers
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• v.63 no.9
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• pp.1286-1293
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• 2014

Typically, studies through the simulation system have been progressed, because the evaluation of the driver's arousal state about the service of a actual train has risk of safety for the driver. When configured event same as the real in simulation system, the ability to cope with an accident situation may be the same each other. But the difference in the state of tension or arousal will occur. In this study, requested to cooperate with the railways in order to escape from these constraints, and the target of the experiment was to real engineer service. I was set about experiment when the train was stopped as safe as possible. As a result, the beta wave of EEG signals that representing complex calculations or anxiety is increased rapidly on the basis of a flag station from at the time of departure. The size of the electrodermal activity signal in response to movement of the body gave a noticeable. In terms of HRV, if the train approach a flag station gradually and the R-R interval is narrowed. So that the driver can be estimated as arousal state. In accordance with this study, if the quantitative standard of arousal state be based on the driver's biosignals will provide, it will be able to take advantage of development the system that would prevent train accidents caused by human error.

• Journal of Navigation and Port Research
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• v.38 no.2
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• pp.141-146
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• 2014

NIR(New Inspection Regime, hereinafter NIR) relating to the PSC(Port State Contorl, hereinafter PSC) has implemented in Asia-Pacific region under Tokyo-MOU from last January 2014. The most noticable difference between NIR and existing TF(Target Factor, hereinafter TF) is to evaluate company performance and to conduct PSC with flexible inspection interval on the basis of Ship Risk Profile; High Risk Ship, Standard Risk Ship and Low Risk Ship. Particularly deficiencies related to ISM Code, more than 5 deficiencies and detention record have a serious effect on the evaluation of Ship Risk Profile. Therefore ship and company are requested to ensure proper implementation of Safety Management System for the changed PSC tendency. Also RO(Recognized Organization, hereinafter RO) and Administration respectively should take suitable actions different to previous measures, such as implementation of cooperation and support system between vessel and company, changing subject and object for avoiding Mannerism in SMS audit, strengthening supervision on RO by Administration and establishment of private-public Partnership network.

• Journal of Broadcast Engineering
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• v.18 no.2
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• pp.185-195
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• 2013

In this paper, we propose a video summarization technique on a smartphone, based on spatiotemporal saliency. The proposed technique detects scene changes by computing the difference of the color histogram, which is robust to camera and object motion. Then the similarity between adjacent frames, face region, and frame saliency are computed to analyze the spatiotemporal saliency in a video clip. Over-segmented hierarchical tree is created using scene changes and is updated iteratively using mergence and maintenance energies computed during the analysis procedure. In the updated hierarchical tree, segmented frames are extracted by applying a greedy algorithm on the node with high saliency when it satisfies the reduction ratio and the minimum interval requested by the user. Experimental result shows that the proposed method summaries a 2 minute-length video in about 10 seconds on a commercial smartphone. The summarization quality is superior to the commercial video editing software, Muvee.

• Journal of KIISE
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• v.45 no.1
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• pp.86-93
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• 2018

When multiple clients share bandwidth and receive a streaming service, HTTP Adaptive Streaming has a problem in that the bandwidth is measured inaccurately due to the ON-OFF pattern of the segment request. To solve the problem caused by the ON-OFF pattern, the proposed PANDA (Probe AND Adapt) determines the quality of the segment to be requested while increasing the target bandwidth. However, since the target bandwidth is increased by a fixed amount, there is a problem in low bandwidth utilization and a slow response to changes in bandwidth. In this paper, we propose a video quality control scheme that improves the low bandwidth utilization and slow responsiveness of PANDA. The proposed scheme adjusts the amount of increase in the target bandwidth according to the bandwidth utilization after judging the bandwidth utilization by comparing the segment download time and the request interval. Experimental results show that the proposed scheme can fully utilize the bandwidth and can quickly respond to changes in bandwidth.