• Transactions of the Korean hydrogen and new energy society
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• v.23 no.6
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• pp.588-597
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• 2012

In the present study, the dispersion characteristics of hydrogen leakage from a Fuel Cell Vehicle (FCV) were analyzed by numerical simulation in order to assess the risk of a hydrogen leakage incident in a long road tunnel. In order to implement the worst case of hydrogen leakage, the FCV was located at the center of a tunnel, and hydrogen was completely discharged within 63 seconds. The Leakage velocity of hydrogen was adopted sub-sonic speed because that the assumption of the blockage effect of secondary device inside a vehicle. The temporal and spatial evaluation of the hydrogen concentration as well as the flammable region in a road tunnel was reported according to change of ventilation operating conditions. The hydrogen was blended by supply air form a ventilation fan, however, the hydrogen was discharged to outside in the exhaust air. It is observed that the efficiency way to eliminate of hydrogen is supply air operating condition under the hazardous hydrogen leaking incident. The present numerical analysis can be provided useful information of ventilation under the hydrogen leaking situation.

• Journal of Convergence for Information Technology
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• v.12 no.5
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• pp.133-138
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• 2022

In previous studies to obtain the residual magnetic flux of the transformer using the leakage magnetic flux, a transfer function was used. The transfer function was consisted with the leakage magnetic flux measured outside the transformer and the residual magnetic flux measured at the moment passing through the two ± residual points. In this study, a method of calculating the ratio of the maximum operating leakage flux to the residual leakage flux was proposed The advantage of this method is to avoid the uncertainty of the transfer function due to current noise. Then, the noise of the sensor was measured to investigate the effect of the drift of the noise on the measurement results. Comparing the residual leakage magnetic flux density with 80nT of the drift noise, 66 times or more at a distance of 10 mm and 5 times or more at a distance of 100 mm were obtained. 100mm was the maximum measurement distance to obtain the residual magnetic flux.

• KSII Transactions on Internet and Information Systems (TIIS)
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• v.8 no.3
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• pp.945-964
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• 2014

In this paper, we investigate the performance of Signal to Leakage and Noise Radio (SLNR) based user scheduling in uplink of multi-cell with large-scale antenna system. Large antenna array is desired to improve the performance in future system by providing better beamforming capability. However, some studies have found that the signal channel is 'hardened' (becomes invariant) when the antenna number goes extremely large, which implies that the signal channel aware user scheduling may have no gain at all. With the mathematic tool of order statistics, we analyzed the signal and interference terms of SLNR in a homogeneous multicell network. The derived distribution function of signal and interference shows that the leakage channel's variance is much more influential than the signal channel's variance in large-scale antenna regime. So even though the signal channel is hardened, the SLNR-based scheduling can achieve remarkable multiuser diversity (MUD) gain due to the fluctuation of the uplink leakage channel. By providing the final SINR distribution, we verify that the SLNR-based scheduling can leverage MUD in a better way than the signal channel based scheduling. The Monte Carlo simulations show that the throughput gain of SLNR-based scheduling over signal channel based scheduling is significant.

• Journal of the Korea Institute of Information Security & Cryptology
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• v.20 no.5
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• pp.59-67
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• 2010

In the paper, we proposed an IM-ACM(Insider Misuse-Access Control Model) for preventing illegal information leakage by insider who exploits his legal rights in the ubiquitous computing environment. The IM-ACM can monitor whether insider uses data rightly using misuse monitor add to CA-TRBAC(Context Aware-Task Role Based Access Control) which permits access authorization according to user role, context role, task and entity's security attributes. It is difficult to prevent information leakage by insider because of access to legal rights, a wealth of knowledge about the system. The IM-ACM can prevent the information flow between objects which have the different security levels using context role and security attributes and prevent an insider misuse by misuse monitor which comparing an insider actual processing behavior to an insider possible work process pattern drawing on the current defined profile of insider's process.

• Proceedings of the IEEK Conference
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• 1999.11a
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• pp.1041-1044
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• 1999

This paper propose a solution to resolve data overflow or leakage when a subscriber receive data to service provider. The set-top box can communicate with a service provider and can inform the service provider its data overflow or leakage. When service provider received this control signal, it changes data transmit rate and transmits data with changed rate. The buffer of set-top box is important because incoming data from a service provider are stored by it.

• 한국정보디스플레이학회:학술대회논문집
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• 2009.10a
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• pp.560-562
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• 2009

In this paper, we proposed a simple method of decreasing the off current generated by degradation for improve the electrical characteristics such as mobility and on/off current ratio by making the line patterns on the pentacene surface between the electrodes using atomic force microscope (AFM) lithography.

• Journal of Information Technology Applications and Management
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• v.16 no.4
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• pp.79-92
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• 2009

With the rising reliance on market estimation through customer analysis in customer-centered marketing, there is a rapid increase in the amount of personal data owned by corporations. There has been a corresponding rise in the customers' interest in personal information protection, and the problem of personal information leakage has risen as a serious issue. The purpose of this research is to develop a diagnosis model for personal information protection that is suited to our country's corporate environment, and on this basis, to present diagnostic instruments that can be applied to domestic corporations. This diagnosis model is a structural equation model that schematizes the degree of synthetic effect that administration factors and estimation items have on the protection of personal information owned by corporations. We develop the model- consisting of the administration factors for personal information protection and the measurement items of each factor- using the development method of standardized structural equation model. We then present a tool through which the administration factors and estimation items verified through this model can be used in the diagnosis for personal information protection in corporations. This diagnostic tool can be utilized as a useful instrument to prevent in advance the leakage of personal information in corporations.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.40 no.8
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• pp.1577-1587
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• 2015

Privacy of financial customers is becoming important due to frequent leakage of personal information. Financial customers, who experience the leakage of personal information, feel threatened by their privacy and this changes customer's awareness about financial institutions or behavioral intentions. By examining the influence relation of personal information security vulnerability of the bank information system with usefulness, trust and attractiveness perceived by bank customers, this study aims to analyze the effect of each variable on bank customers' willingness to stay.

• Journal of IKEEE
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• v.27 no.4
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• pp.644-649
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• 2023

As the cell spacing decreases during the scaling process of DRAM(Dynamic Random Access Memory), the reduction in STI(Shallow Trench Isolation) thickness leads to an increase in sub-threshold leakage due to the passing word line effect. The increase in sub-threshold leakage current caused by the voltage applied to adjacent passing word lines affects the data retention time and increases the number of refresh operations, thereby contributing to higher power consumption in DRAM. In this paper, we identify the causes of the passing word line effect through TCAD Simulation. As a result, we confirm the DRAM operational conditions under which the passing word line effect occurs, and observe that this effect alters the proportion of the total leakage current attributable to different causes. Through this, we recognize the necessity to consider not only leakage currents due to GIDL(Gate Induced Drain Leakage) but also sub-threshold leakage currents, providing guidance for improving DRAM structure.

• Journal of the Semiconductor & Display Technology
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• v.19 no.2
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• pp.96-99
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• 2020

According to brilliant development of smart devices, many related services are being devised. And, almost every service is designed to provide user-centric services based on personal information. In this situation, to prevent unintentional leakage of personal information is essential. Conventionally, ID and Password system is used for the user authentication. This is a convenient method, but it has a vulnerability that can cause problems due to information leakage. To overcome these problem, many methods related to face recognition is being researched. Through this paper, we investigated the trend of user authentication through biometrics and a representative model for face recognition techniques. One is DeepFace of FaceBook and another is FaceNet of Google. Each model is based on the concept of Deep Learning and Distance Metric Learning, respectively. And also, they are based on Convolutional Neural Network (CNN) model. In the future, further research is needed on the equipment configuration requirements for practical applications and ways to provide actual personalized services.