• Proceedings of the IEEK Conference
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• 1998.06a
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• pp.126-129
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• 1998

In order to control the flow of traffics in ATM networks and optimize the usage of network resources, an efficient control mechanism is necessary to cope with congestion and prevent the degradation of network performance caused by congestion. This paper proposes a new UPC(Usage Parameter Control) mechanism that varies the token generation rate and the buffer threshold of leaky bucket by using a Neural Network controller observing input buffers and token pools, thus achieving the improvement of performance. Simulation results show that the proposed adaptive algorithm uses of network resources efficiently and satisfies QoS for the various kinds of traffics.

• Journal of the Korean Institute of Telematics and Electronics A
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• v.33A no.2
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• pp.23-31
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• 1996

This paper proposes a new UPC(usage parameter control) mechanism that varies the token generation rate of leaky bucket by observing virtual buffer, thus achieving an improvement of performance. An acceptance of a call in B-ISDN is determined by call admission control. A UPC that polices the agreed traffic parameters of a call and takes appropriate actions to prevent congestion in networks. The cell loss probability of conventional UPC is far from that of ideal UPC. The proposed mechanism has a better policing ability and response time for nonconforming call. The proposed mechanism uses ON-OFF model as input traffic. The results of simulation show the efficiency of the proposed mechanism.

• 한국정보컨버전스학회:학술대회논문집
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• 2008.06a
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• pp.75-86
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• 2008

This paper presents the design, implementation, and evaluation of the RFID Guardian, the first-ever unified platform for RFID security and privacy administration. The RFID Guardian resembles an "RFID firewall", enabling individuals to monitor and control access to their RFID tags by combining a standard-issue RFID reader with unique RFID tag emulation capabilities. Our system provides a platform for coordinated usage of RFID security mechanisms, offering fine-grained control over RFID-based auditing, key management, access control, and authentication capabilities. We have prototyped the RFID Guardian using off-the-shelf components, and our experience has shown that active mobile devices are a valuable tool for managing the security of RFID tags in a variety of applications, including protecting low-cost tags that are unable to regulate their own usage.

• Proceedings of the KIEE Conference
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• 2006.07b
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• pp.1079-1080
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• 2006

This paper presents the methods to save energy by using load consumption pattern analysis. Base on the substation annual power usage data, the characteristic of the substation power consumption have investigated. With this investigation effective electrical billing condition and the control target load has been determined. Most of power usage comes from the motor car, so power system and load table of motor car were reviewed. And in the metropolitan area the peak power consumption occurs at summer or winter rush hours because of its typical characteristics. From this data control point of time are determined. Through the whole study the methode to control the power Peak consumption are proposed and prototype was designed.

• Transactions of the Korean hydrogen and new energy society
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• v.30 no.2
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• pp.155-162
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• 2019

The energy management technology for an independent fuel cell-battery hybrid system is developed for a household usage. To develop an efficient energy management technology, a simulation model is first developed. After the model is verified with experimental results, three energy management schemes are developed. Three control techniques are a fuzzy logic control (FLC), a state machine control (SMC), and a hybrid method of FLC and SMC. As the fuel cell-battery hybrid system is used for a house, battery state of charge (SOC) regulation is the most important factor for an energy management because SOC should be kept constant every day for continuous usage. Three management schemes are compared to see SOC, power split, and fuel cell power variations effects. Experimental results are also presented and the most favorable strategy is the state machine combined fuzzy control method.

• Journal of the Korea Institute of Building Construction
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• v.20 no.6
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• pp.497-504
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• 2020

In Korea construction industry, researches are being conducted to reduce the disasters related tower crane due to the increase of tower crane's usage and accidents continuously. Although the usage amount of remote control tower crane has been increasing recently, the research on remote-control tower crane is insufficient. In this study, the importance ranking of remote control tower crane's accident factors derived by AHP analysis. AHP questionnaire was conducted to engineers (or operators) like construction site engineer, construction manager, safety engineer, and tower crane operator, who have more than 10 years career. The results of AHP analysis reveal that top ranking factor of remote control tower crane's accident is lifting work for materials. Therefore, the high importance factors should be managed, and taken the priority measures for reducing the tower crane accidents by using the results of this research.

• Journal of Digital Contents Society
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• v.13 no.4
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• pp.501-516
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• 2012

The purpose of this study is to explore the fundamental nature and meanings of the experiences of university students with regard to their smartphone usage in order to prevent smartphone addiction and provide guidelines to develop effective interventions. Nine university students who were currently enrolled in an university located in a Korean province participated in this study. In-depth interviews were conducted from June of 2012 to July of 2012, and data were analyzed using Colaizzi's phenomenological qualitative method. As a results, five theme and 40 subthemes of experiences of problematic smartphone usage were identified. Those themes include 1) a desperate try to connect with others(exposing oneself without appropriate self-protection, seeking emotional comfort, hurt and mistrust); 2) excessive use of smartphone and loss of self-control(more smartphone usage over computer/over-immersion/excessive usage/habituation, loss of self-control); 3) psychological difficulties(excessive attachment and dependence, separation anxiety, clingingness, reduced patience) ; 4) threats to daily functioning (changes in priorities, regressed independent daily functioning, irregular daily patterns, health problems, interruptions from free messenger, academic difficulties); 5) potential for recovery(conflictual feelings and doubts over smartphone usage, importance of interpersonal(face-to-face) communications, willingness to cut down the use, hope for recovery). This study provided suggestions for the prevention effort against smartphone addiction.

• Proceedings of the Korean Institute of Communication Sciences Conference
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• 1991.10a
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• pp.179-182
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• 1991

In this paper, we survey traffic control issues for the B-ISDN based on the ATM. We first investigate traffic descriptors to represent the characteristics of various ATM traffics in a standardized form. Also, we examine key issues related to the connection admission control, usage parameter control, network parameter control, priority control, and congestion control.

• PNF and Movement
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• v.17 no.1
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• pp.57-68
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• 2019

Purpose: This study is an investigation of the effects of long-term smart phone usage and of stretching on muscle stiffness, concentration, and visual acuity. Methods: Forty healthy young adults voluntarily participated in the study and were measured for muscle stiffness, concentration, and visual acuity before smartphone usage and after 30 minutes, 60 minutes, and 90 minutes of smartphone usage. The participants were randomly allocated to the intervention group (n=20) and the control group (n=20). Five minutes after the stretching exercise and eye exercise intervention, the participants were remeasured. Results: After long-term smartphone usage, increases in muscle stiffness and concentration were statistically significant (p<0.05), whereas decreases in visual acuity were statistically significant (p<0.05). After the stretching exercise and eye exercise intervention, muscle stiffness significantly decreased (p<0.05) and visual acuity significantly increased (p<0.05). Concentration, according to the stretching exercise and eye exercise intervention, showed no significant pre- or post-test difference. Conclusion: The results from this study indicate that long-term smartphone usage effectively improved concentration but increased muscle stiffness and decreased visual acuity. Appropriate stretching and eye movement during long-term smartphones usage should mitigate the effects on muscle stiffness and visual acuity. Furthermore, smartphones should be considered an effective tool for concentration training when coupled with the development of appropriate applications.

• Smart Media Journal
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• v.13 no.1
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• pp.18-23
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• 2024

Power efficiency management in smart farms is important due to its link to climate change. As climate change negatively impacts agriculture, future agriculture is expected to utilize smart farms to minimize climate impacts, but smart farms' power consumption may exacerbate the climate crisis due to the current electricity production system. Therefore, it is essential to efficiently manage and optimize the power usage of smart farms. In this study, we propose a system that monitors the power usage of smart farm equipment in real time and predicts the power usage one hour later using GRU. CT sensors are installed to collect power usage data, which are analyzed to detect and prevent abnormal patterns, and combined with IoT technology to efficiently manage and monitor the overall power usage. This helps to optimize power usage, improve energy efficiency, and reduce carbon emissions. The system is expected to improve not only the energy management of smart farms, but also the overall efficiency of energy use.