• Journal of Korean Society of Transportation
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• v.12 no.3
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• pp.49-64
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• 1994

The development of a mathematical modular framework based on Petri Network theory to model a traffic network is the subject of this paper. Traffic intersections are the primitive elements of a transportation network and are characterized as event driven and asynchronous systems. Petri network have been utilized to model these discrete event systems; further analysis of their structure can reveal information relevant to the concurrency, parallelism, synchronization, and deadlock avoidance issuse. The Petri-net based model of a generic traffic junction is presented. These modular networks are effective in synchronizing their components and can be used for modeling purposes of an asynchronous large scale transportation system. The derived model is suitable for simulations on a multiprocessor computer since its program execution safety is secured. The software pseudocode for simulating a transportation network model on a multiprocessor system is presented.

• Journal of the Korean Society of School Health
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• v.16 no.2
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• pp.25-34
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• 2003

Instroduction: The purpose of this study was to investigate safety education-related backgrounds and safety behaviors of elementary school children at a local area in Jeonbuk province. Methods: Study subjects were 308 5th and 6th graders from 6 schools located in J City and the data were collected from June 16-27, 2003. Research instrument to test safety behaviors was 4-points summated scale (Cronbach${\alpha}$= .94) composed of 54-items with three sub-categories school life safety (${\alpha}$= .88), traffic safety (${\alpha}$= .86), and daily life safety (${\alpha}$= .84), The data was analyzed by percentage, x2-test, t-test, ANOVA and Duncan test using SPSS/PC 10.0. Results: 1. Safety Education-related Characteristics: Safety education was mostly conducted during extracurricular hour as picnic (37%) and regular class (37.2%); and the instructors of safety education were school nurse (33.2%), classroom teacher (30.9%), and parents (23.4%) in order. About two third (71.0%) of the subjects have had many kinds of school event program such as essay writing, poster drawing, oratorical contest in the course of safety education According to gender, girl students was more favorable about school events as a effective safety education measure (x2=9.188, p= .010); and according to school location, nural school taught more at moming & closing session (x2=7.383, p= .025), by school nurse or classroom teacher (x2=36.574, p= .001), and had more frequent (x2=63.337, p= .001) safety education class. 2. Practice of safety behaviors: Mean scores of safety behaviors was $106.9{\pm}24.92$ out of 162 points. According gender, the scores of girl students (t=-3.296, p= .001) were significant higher than boy students. But there was not any significant difference according to school area According to safety education-related characteristics, the scores of safety behaviors was significantly higher in the group who thought that school event program was more effective on safety education (F=4.024, p= .019), and who were more interested in current safety education class (F= 10.203, p= .001) Conclusions: From the above findings, the authors concluded that school-based safety education was mainly conducted at extra-curricular and regular class, and by school nurse or classroom teacher in elementary school. Even though the mean scores of safety behaviors of elementary school children was in medium level, those. were significant higher in girl students and in rural school children. And extra-curricular activities and school event programs were suggested as more effective strategies for school-based safety education Based on the above findings, safety education class can be recommended in regular curricular basis; and various extracurricular activities and school event programs need to be developed for more effective school-based safety education. In addition, further study on gender-specific factors on safety behaviors and nationwide survey on school-based safety education should be needed.

• The KIPS Transactions:PartA
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• v.9A no.2
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• pp.181-190
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• 2002

IEEE1394 is a de facto standard for the home network interfaces of digital multimedia home devices including digital A/V systems, digital camcorders, and PCs. Recently, it has been used in applications to guarantee the real-time characteristics such as home automation system and IICP (Instrument and Industrial Control Protocol). In order to guarantee real-time requirements in these IEEE1394-based real-time applications, this thesis proposes the software architecture of an IEEE1394 based home network that supports the guarantee for service's react-time characteristics. The proposed architecture has a real-time IEEE1394 device driver and event service architecture for guarantee real-time characteristics. The real-time device driver supports priority-based queueing of packets and mechanism to reduce the interrupt latency time in ISR. The event service architecture supports a real-time events delivery based on home network service using real-time event channel. This architecture can accommodate the real-time requirements of various applications and services such as digital multimedia services with QoS guarantees. home automation system required real-tine characteristics.

• 한국ITS학회:학술대회논문집
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• 2008.11a
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• pp.428-436
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• 2008

• Proceedings of the CALSEC Conference
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• 2005.03a
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• pp.120-122
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• 2005

• Proceedings of the Korean Nuclear Society Conference
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• 2005.10a
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• pp.534-535
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• 2005

• Journal of the Korea Computer Industry Society
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• v.9 no.3
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• pp.121-128
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• 2008

This paper suggested a location-based traffic information service system using TPEG and GIS. Measurement technique, location server, applied service technique, and linkage technique with database were used to provide the location-based traffic information service. In particular, TPEG-RTM includes location information and load traffic message. The location information to be included in each message displayed a specific point, section or region limit of the load. Actually, because it was impossible to receive data using TPEG receiver, a proposed program included in this paper was used to produce an arbitrary database and read it, Also, TPEG event happened time was indicated on the map for matching test of a TPEG message and WGS84 coordinate, and finally it was verified with art example of a vehicle approaching to an event happened place.

• Journal of Communications and Networks
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• v.15 no.3
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• pp.301-311
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• 2013

This paper proposes a policy-based quality of service (QoS) management framework for adaptive routing decisions. We present an approach considering interior gateway protocol (IGP) for path discovery mechanisms and QoS-aware policies for configuring the network elements. The integration of the aforementioned modules into this policy-based network management (PBNM) system is demonstrated by conducting experiments in a real environment, the hellenic public administration network SYZEFXIS. These experiments combine different traffic conditioning mechanisms through event detectors, consider IP service level agreement mechanisms that interoperate with the PBNM system and analyze the enforcement of IGP and QoS policies. Finally, validation and measurement tools are used to prove the efficiency of this framework. It is shown that this architecture offers significantly increased performance and learning capabilities, while the PBNM system achieves adaptive QoS routing through automated configuration considering the avoidance of suboptimal routing issues or under-performance conditions of the network entities.

• Nuclear Engineering and Technology
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• v.50 no.5
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• pp.745-750
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• 2018

New exercise technology such as the virtual reality (VR)-based exercise system is required to meet soaring demand for target participants in exercises and to alleviate the difficulties in personnel mobilization through an alternative approach to the exercise system. In a previous study, event tree methodologies were introduced in setting up an exercise scenario of a VR-based radiological exercise system. In the scenario, the locations at which major events occur are rephrased as nodes, routes as paths, and public response actions as protective actions or contents of an exercise at individual locations. In the study, a model for estimating effective doses to the participants is proposed to evaluate the exercise system, using the effective dose rates at particular times and locations derived from a computer program. The effective dose received by a student when she/he follows a successful route is about a half of the dose received when she/he does not follow the exercise guide directions. In addition, elapsed time to finish an exercise when following a successful route is less than one-third of the time spent to finish an exercise when following the guide's directions.

• The Journal of the Institute of Internet, Broadcasting and Communication
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• v.16 no.4
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• pp.97-108
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• 2016

In this paper, we consider a cooperative monitoring network, which consists of a large number of UAVs, in order to promptly detect event in a disaster area. A command center may not be able to control each UAV individually due to resource constraints. Therefore, UAVs need to autonomously construct a mobile monitoring network in order to maximize monitoring coverage and to adapt the network formation according to environment changes in the disaster area. To that end, we propose multiple UAVs-based cooperative monitoring schemes that uses virtual forces. In this monitoring scheme, an effective monitoring is enabled by extending monitoring coverage using each UAV's circle movements. The UAVs-based monitoring network can also be splitted or merged in order to increase the monitoring effectiveness. Through simulations, we show that the proposed scheme can effectively monitor a large area and achieve a high event detection ratio.