• Journal of the Optical Society of Korea
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• v.20 no.3
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• pp.358-362
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• 2016

We present a new scheme for optical encryption of a binary image. In our method, the original binary data page is first divided into two identical pages. In each data page, the “on” and “off” pixels are represented by two discrete phases that are 90° apart. The first page corresponds to the phase conjugation of the second page, and vice versa. In addition, the wavefront of the two data pages is changed simultaneously from planar to spherical, for better encryption. The wavefront modification is represented by an extra phase shift, which is a function of position on the wavefront. In this way the two separate pages are both encrypted, and therefore the pages cannot be distinguished in a CCD. If the first page is used as an encrypted data page, then the second page is used as the decryption key, and vice versa. The decryption can be done by simply combining the two encrypted data pages. It is shown in our experiment that encryption and decryption can be fully accomplished in the optical domain.

• Journal of the Korean Home Economics Association
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• v.42 no.5
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• pp.127-143
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• 2004

This study examined the direct and indirect influences of adolescents' self-esteem, impulsiveness, departments of school, perceived communications with mothers and peer support on internet-related delinquencies. The study consisted of 555 second-year students from a vocational, academic oriented girl's high schools that were located in Busan. Data analysis was made through Two-Way ANOVA, Pearson's Correlation, Multiple Regression, and Path Analysis by using SPSS WIN 10.0. The results of this study is described as follows. First, internet-related delinquencies were committed by male students more than by female students. Second, problematic communications with mothers was most directly influenced by internet-related delinquencies of high school students of both sexes and was indirectly influenced by self-esteem and impulsiveness. Third, impulsiveness was directly influenced by internet-related delinquencies in both male and female students. In male students, their school departments indirectly influenced internet-related delinquencies by way of open communication with mothers, peer support, self-esteem, and impulsiveness. In female students, school departments directly influenced on internet-related delinquencies and indirectly by way of peer support, self-esteem and impulsiveness. Internet-related delinquencies by male and female students were not directly influenced by peer support and self-esteem. But peer support did have indirect effects on internet-related delinquencies by way of self-esteem and impulsiveness, and self-esteem also had indirect effects by way of impulsiveness.

• School Mathematics
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• v.4 no.2
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• pp.261-282
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• 2002

This study intended to search for the way of NIE use as follows: 1) Setting up theoretical base about the way of NIE use to math loaming in primary school. 2) Analyzing the course mathematising through NIE use in math learning in practice. 3) Searching for the way of NIE use to aim at mathematising. As the result, this presented NIE model for mathematising according to the character of each step of the mathematising course. This paper says two things : The first, the way for using learning materials as reonstructing articles of newspapers to teach math learning 1) is searched for each information, scrapped to materialize. 2)is to extract the contents of NIE teaming available to the field and the unit of math curriculum. 3) searches for and applies the model for math NIE teaming. 4) makes up learning materials for each level using articles and presents the matters of deepening and supplement suitable for students. The second, the way for teaching math NIE with a view to helping students' mathematising during the course of teachers' math teaming. 1) reconstructs materials chosen by students' reality. 2) should offer students' communication and abundant context materials which mathematical model is possible. 3)needs to guide students to have motivation teaming so that they can mathematise their real matters by rediscovery 4) progresses mathematical activity using newspapers so that they can apply to new reality by applying informed Idea.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.28 no.6
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• pp.408-413
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• 2015

Road lighting has emerged in importance as an essential system to secure safety and visibility for drivers and pedestrians. According to the Road Lighting Standards (KS A 3701), the luminance uniformity (U0) should be 0.4, the luminance uniformity for lanes (UI) should be 0.5, and a threshold increment (TI) of 10% should be satisfied. In this study, we conducted simulations using the Relux program in which the secondary optical lens was applied to a 21 W engine. Ten LED engines were installed on a two-way four-lane road, and the simulation result satisfied the requirements with U0 0.47, UI 0.63 and TI 8%. The U0, UI, and TI were compared with the angle of the LED streetlight varied in the range of $9^{\circ}{\sim}15^{\circ}$ with $0.5^{\circ}$ intervals. The range was selected as ${\pm}25%$ of the standard inclination angle of $12^{\circ}$ according to the Road Lighting Standard. The U0 was high and the UI and TI were low when the tilting angle was in the range of $9.5^{\circ}{\sim}10.5^{\circ}$. Consequently, an optimum-design of lighting distribution was obtained for the concrete two-way four-lane road when the inclination angle was $9^{\circ}$.

• Journal of the Korea Convergence Society
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• v.6 no.4
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• pp.113-119
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• 2015

Currently, we are presenting an alternative educational environment for the normal student of education rules failure of the only that has been the school system student. The study for students with disabilities, it is designed especially to be able to use difficult disabilities the use of hand. Development objectives of the learning video e-learning system of persons with disabilities, is that to be able to capable of self-directed learning of disabled students. Configuration of e-running system, Web-based multimedia system, utilizing the system that will change the video conferencing system and voice to a character hearing impaired students through the chat system is 1:1 by communication, and teachers it is possible to perform two-way communication. A learning disability e-learning system developed in this paper between teachers and students with disabilities 1:1 training is conducted using a two-way communication algorithms.

• The Journal of the Institute of Internet, Broadcasting and Communication
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• v.18 no.4
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• pp.211-218
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• 2018

Recently, various technologies related to IIoT are introduced continuously due to the spread of IoT and smart factory industries. This paper proposes the construction of a two-way wireless network system for monitoring plant equipment using these various technologies. The main technologies used in this thesis are design techniques for micro sensor nodes to monitor facility conditions at various sites, MQTT technology for wireless communication between local server and sensor nodes and Node-RED based design technologies, which store data collected and can be easily presented to users via wired and wireless wires. In addition, a wireless two-way camera system was also implemented in which the screen images of the site can be viewed in the situation room according to the instructions of the situation room when determining abnormal conditions.

• Journal of Advanced Navigation Technology
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• v.27 no.4
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• pp.453-456
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• 2023

Fighter jets employ guided missiles equipped with seekers to counter enemy air threats. Short range guided missiles(SRM) usually carry infrared(IR) seekers and are used to engage targets within visual range. On the other hand, medium range guided missiles(MRM) often utilize radio frequency(RF) seekers to engage targets beyond visual range. Medium range guided missiles do not activate their seekers until they reach the detection range of the seeker, and the aircraft's radar guides them for a certain distance. This guidance method is called Missile Data Link(MDL), and it can be implemented in either one-way or two-way communication modes, depending on the missile's communication system. In this paper, we discuss MDL based on these two communication modes, along with the integration of RADAR, mission computers, and guided missiles.

• IEMEK Journal of Embedded Systems and Applications
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• v.5 no.3
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• pp.118-127
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• 2010

Inter-vehicle communication is one of the most important parts in Intelligent Vehicle System. Through this communication, drivers can recognize what is happening out of their sights, such as the freezing condition of the street, traffic accidents, and so on. Each car in IVS gives various services to the drivers after analyzing those received information from cars or a base station. If the message is, however, exchanged from car to car directly, the computation cost which is needed for all the car to authenticate the transmitted message between nearby cars is tremendously high. Therefore, one can naturally think that the message communication between cars is performed with the help of the base station to reduce the computation cost. In this case where the base station collects all the information transmitted from cars and broadcasts them nearby, there should be an efficient way both for the base station to authenticate the car message within its communication range and for the car to authenticate the information received from the base station. In this paper, we present a two-way authentication protocol using a hash chain to efficiently exchange GPS information between a car and a base station. This information can be used to provide a driver with the navigation which displays all the moving cars around him in real time. When a car goes into an area of a base station, the car authenticates itself to the base station using its private key of PKI, sends a commitment of a hash chain, then starts to send a message with the hash value for authentication. The message includes GPS information, driver's status and so on. The base station also authenticates itself to the nearby cars using its private key, transmits the commitment of the hash chain, and sends all the messages gathered from cars with authentication information.

• Journal of Convergence for Information Technology
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• v.9 no.12
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• pp.244-251
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• 2019

This study is to investigate the factors influencing the problem solving ability of dental hygiene and students' communication ability and critical thinking and autonomous educational climate. The subjects were 249 dental hygienists who attended two university from May 20 to June 1, 2018. Statistical analysis was performed with mean, t-test and one-way ANOVA. The overall mean of critical thinking tendency was 3.47 points, the total mean of communication life was 3.48 points. The overall mean of autonomous educational climate was 3.14 points and the total mean of problem solving ability was 3.40 points. The higher the critical thinking disposition score, the higher the problem solving ability. The higher the satisfaction of the major, the higher the problem solving ability. Therefore, if the program to improve communication ability, critical thinking tendency, and autonomous educational climate of college students majoring in dental hygiene is expected to improve the problem solving ability.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.8 no.2
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• pp.295-303
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• 2004

In this Paper, we discuss an active TCP link of unsynchronized transmission mode network in two-way traffic and the Improvement of its traffic patron thorough the network pathway of protocol is shown. This is because the traffic pattern is performed on the basis of existing windows which are distributing information in several periods of time in the way of interfacing LTS control module, which is controlling by an information of exceeding the time limit of feedback loop determined by RTP, with TCP. The simulation to utilize this efficiently is performed with the circumstance of bench mark based on physical modeling of the self-similarity traffic in the performance of TCP. In this paper, we use a methodology to understand and evaluate the effect of change of transmitting protocol in sticks under the condition of the self-similar traffic in two-way network and it is shown that an improvement of congestion control by self-similarity under a heavy condition.