• Journal of the Institute of Electronics Engineers of Korea SP
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• v.37 no.5
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• pp.9-20
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• 2000

In this paper we compare two frequency domain digital watermarking methods for digital Images, namely DCT(Discrete Cosine Transform) based and DFT(Discrete Fourier Transform) based methods. Unlike DCT coefficients, which always have real values, DFT coefficients normally have complex values Therefore, the DFT coefficients have amplitude and phase components Among them, the phase components are known to carry more Important information for the Images. So, we insert the watermark to the phase of the DFT coefficients only This DFT watermarking method is compared with the conventional DCT based watermarking method for the object-based watermarking problem. Experimental results show that the DFT-phase based method IS more robust to general Image processing attacks including resize, lossy compression(JPEG), blurring and median filtering. On the other hand, the DCT based method is more robust to the malicious attack which inserts different watermarks.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2017.05a
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• pp.327-330
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• 2017

In recent years, Drone(lightweight unmanned aerial vehicle) is used for broadcast shooting, disaster scene, leisure, observation and military purposes. However, as the use of drones increases the threat of hacking is also rising. Especially when a flying drone is seized, a dangerous situation can occur which is abused regardless of the driver's intention. Already in Iran and China, there is a case of hacking and stealing the drones of other countries under reconnaissance. In this paper, we analyze the security vulnerabilities of Wi-Fi and Bluetooth communication in wireless network which are used in drones for stealing the commercial drones. The results provide a countermeasure to safeguard the drones against attempts by the unauthorized attacker to take out the drones.

• Journal of the Health Care and Life Science
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• v.10 no.2
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• pp.253-258
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• 2022

It is a widely known fact that MAC addresses can be collected using Wi-Fi from mobile phones that people carry. However, since collecting and using MAC addresses without individual consent entails many legal problems, it was difficult to actively utilize them. In order to prevent invasion of privacy information due to unintentional exposure of these MAC addresses in recent years, the method of protecting privacy information by exposing a randomly generated virtual MAC address rather than the MAC address of the actual device is applied to all mobile devices. is becoming By exposing a randomly generated virtual MAC address on a device, it becomes impossible to identify and track an individual using the MAC address. However, the fact that various facts can be estimated through MAC Address collection is still valid. By expanding the application of Random MAC Address, the possibility of invasion of privacy information has been completely removed from the MAC address that has been raised in the past, so that it can be used more actively than in the past. In this paper, we propose a method for automatically collecting and analyzing statistical information of hospital visitors using MAC addresses. The collection of hospital visitors using MAC Address is a low cost and relatively accurate method, and the analysis of hospital visitors through steady collection can provide very objective and scientific evidence for hospital operation.

• Journal of Digital Convergence
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• v.12 no.1
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• pp.105-114
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• 2014

There are many studies on the adoption intentions for mobile banking. But there are no apparent effect on the popularity of it. This is so because the users have resistance to innovation on Mobile Banking. Therefore, it is necessary to identify empirically the problem of user resistance. In this paper, we identified hindrance factors of mobile banking with previous papers. And then we conducted empirical study by survey reply from undergraduates and graduate students in China. The results of this study are as follows. Social Influence and Perceived Complexity have positive effect on Perceived Risk, and Trust has negative effect on Perceived Risk. Perceived Security and Perceived Protection of Private information have no effect on Perceived Risk. Perceived Risk has effect on User Resistance. The significance of this paper is that financial institutions and telecommunications companies of China could potentially establish new and more accurate strategies based on the resistance factors identified in this paper to gain more profits.

• Environmental and Resource Economics Review
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• v.15 no.2
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• pp.147-175
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• 2006

This paper attempts to incorporate three important factors-perceptions, behavior and valuation-in analysing consumers' responses to health risks from environmental pollutants. Using a survey sample of 500 consumers in the Chonbuk province area, this paper empirically investigated determinants of risk perceptions from using tap water as drinking water. Most consumers were considerably concerned about health risks from drinking tap water. Moreover, those subjective concerns were not random, but were systematically related to individuals' demographic variables such as age, gender, and family size. Those subjective beliefs also influenced respondents' purchase intentions on safer water bottles, in response to a contingent behavior question of presenting two types of water bottles. The technical risk information provided in the survey had significant effects on purchase intentions only when it was interacted with respondents' actual averting practice. In addition, the sample selection effects were present by eliminating respondents who decided not to purchase either of two types of water bottles. The potential selection bias had impacts on the coefficients of the price difference variable, and subsequently the estimates of the price increments for health risk reductions.

• Journal of KIISE:Computer Systems and Theory
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• v.36 no.5
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• pp.396-403
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• 2009

An anonymous asymmetric fingerprinting protocol combined with watermarking techniques, is one of the copyright protection technologies keeping both right of a seller and that of a buyer, where a seller and an anonymous buyer perform such a protocol that employs various cryptographic tools in order that the seller does not know the exact watermarked copy that the buyer receives, while inserting an invisible non-removable fingerprint i.e., each different unique watermark, into each copy of the digital content to be sold. In such a protocol innocent buyers are kept anonymous during transactions, however, the unlawful reseller is unambiguously identified with a real identity as a copyright violator. In 2007, Yong and Lee proposed an anonymous asymmetric fingerprinting scheme with trusted third party. In this paper we point out the weakness of their scheme such as: the buyer with intention can remove the fingerprint in the watermarked content, because he/she can decrypt the encrypted fingerprint with a symmetric key using man-in-the-middle-attack; a real identity of a buyer can be revealed to the seller through the identification process even though he/she is honest. Furthermore, we propose an improved secure and efficient anonymous asymmetric fingerprinting scheme which enables to reduce the number of communication between the participants.

• The KIPS Transactions:PartA
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• v.8A no.4
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• pp.391-398
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• 2001

To design and develop secure operating systems, the BLP (Bell-La Padula) model that represents the MLP (Multi-Level Policy) has been widely adopted. However, user\`s security level in the most developed systems based on the BLP model is inherited to a process that is actual subject on behalf of the user, regardless whatever the process behavior is. So, there could be information disclosure threat or modification threat by malicious or unreliable processes even though the user is authorized in the system. These problems can be solved by defining the subject as (user, process) ordered pair and by defining the process reliability. Moreover, when the leveled programs which exist as objects in a disk are executed by a process and have different level from the process level, the security level decision problem occurs. This paper presents an extended BLP (E-BLP) model in which process reliability is considered and solves the security level decision problem. And this model is implemented into the Linux kernel 2.4.7.

• Korean journal of communication and information
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• v.55
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• pp.50-73
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• 2011

This paper investigates the effectiveness of Real-Name System on Internet, which has been applied to some Internet service provider bulletin boards in Korea. The goal of the Real-Name system on the Internet is controlling expression of slanderous or abusive language. The effectiveness of the regulation is dependent on the people's perceptions and attitude toward to the legislation. This empirical study examines the antecedents that affect the perceptions and attitude toward the regulation. Further, we investigate the relationships among variables such as internet public sphere participation, attitude to the regulations, and intention to choose detours. Results of regression analysis show that the younger and the more progressive individuals are, the more they oppose the implementation of the law. Also, it was found that people who have more political interest and participate more actively in public sphere via internet, tend to oppose the law. Structural equation models reveal that participation in online public sphere drives negative attitudes about the regulation. In addition, people with negative perceptions about the law tend to choose the detours such as 'cyber asylum' and 'service asylum'.

• Journal of the Korea Society of Computer and Information
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• v.27 no.12
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• pp.17-27
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• 2022

In this paper, ED-H algorithm, an optimal real-time scheduling algorithm dealing with the characteristics of the integrated energy harvester system with a capacitor, is extended to satisfy the time constraint under the blackout state which is a deliberate power-off state by an intelligent power management unit adopted in the system. If the power supply system does not have enough energy, it temporarily shuts off the power supply to protect the circuit and capacitor and resumes the supply again when the capacitor is fully charged, which may delay the task execution during these blackout states by calculating the time according to the occurrence of the events. To mitigate the problem, even if task execution is delayed by the original ED-H algorithm, the remaining time of the subsequent time units no longer can afford to delay the execution of the task is predicted in the extended algorithm and the task is forced to be scheduled to meet the time deadline. According to the simulation results, it is confirmed that the algorithm proposed in this paper has a high scheduling performance increase of 0.4% to 7.7% depending on the characteristics of the set of tasks compared to the ED-H.

• Journal of Music and Human Behavior
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• v.13 no.1
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• pp.89-110
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• 2016

This study examined the effect of an interactive instrument playing program on the social interaction of adults with autism spectrum disorder (ASD). A single subject design with multiple baselines across participants was applied, and three adults with severe ASD in their late 20s living at a group home participated in this study. Participants received a total of 25 group sessions. During the intervention, participants engaged in structured instrument playing in which initiation and response to socially interactive behaviors were musically cued, and target behaviors were reinforced in the musical environment. At pre- and posttest, the frequency of initiation of and responding to social interaction behaviors were recorded and analyzed. The results of this study showed that the frequency of both initiation of, and response to, social interaction increased for all participants during the intervention phase, compared to the baseline phase. This result demonstrates that interactive instrument playing increased social behaviors of adults with ASD. It also shows that musically delivered social information can facilitate adults with ASD understanding the intention of social partners in social contexts and motivate this population to engage in social interaction.