KJC Korea
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It should be considered effective quality measurement scheme to stably provide various realtime TV services such as IPTV, WebTV, SmartTV over IP-based networks which provide best-effort services. In this study we have presented No-Reference S/W tools in order to objectively measure video quality of realtime TV services using the network-related QoS metrics and user-related QoE metrics. We have compared with commercially available measuring instruments to verify validity of our objective quality assessment scheme using the network-related QoS metrics. Also We have compared with subjective quality assessment by expert group to verify validity of our objective quality assessment scheme using the user-related QoE metrics.

This study developed an adaptive e-learning system that could provide effective instruction methods. The proposed adaptive e-learning system classified learning content into the conceptional content, principal content, and procedural content; and, by providing an appropriate conceptual model, inquiry model, and cognitive-apprehensive model, developed an effective instructional method. The proposed adaptive e-learning system was applied to college students and the learning effects were analyzed. The learners were divided into an experimental group and comparative group for an analysis of the learning effects. An independent t-test was performed for the experimental research. The results indicate that the proposed adaptive e-learning system produced highly improved learning achievement. In addition, the proposed adaptive e-learning system resulted in positive effects in both male and female learner groups.

In this paper, the motion-haptic feedback system is presented in order to provide the same sensation to players as if they enjoys a real ski on ski slope. For maximizing immersive sensation, player’s motion is measured by two inertia measurement units (IMUs) and the measured motion is used for natural interaction with virtual environment. To simulate the behavior of player’s ski plates, three timing belts and five DC motors are incorporated into the proposed system. The three-timing belts and three-DC motors are also used in order to provide horizontal acceleration to players. Furthermore, two additional DC motors are applied to the proposed system for creating forward-backward acceleration. Therefore, the players can sense realistic motion-haptic feedback as if they enjoy real ski on ski slope.

With Korean governmental policy of ‘Enforcement Strategy of Smart Education‘, importance of mobile education content authoring tool which can be used in educational practice and makes it possible to provide an efficient education is growing significantly. In this paper, we classified and analyzed mobile educational Apps as a base study for the design of mobile educational content authoring tool. First, we propose a classification method of educational mobile Apps based on the book category system, and classified educational mobile Apps within the top 100 in download count according to the proposed classification method. Moreover, we analyzed the major functions of Apps by categories and decided development targets and direction based on the results of such analysis.

There are studies on biometric based authentication using physiological or behavioral characteristics of the user to improve reliability of user authentication. This study suggests the user authentication method using key input patterns and hand shapes when the user inputs authentication information. When behavioral characteristics are used for user authentication, there is a disadvantage for the authorized user to fail for user authentication and to be prohibited to access the information system. This study suggested a method of granting access to the authority system by differential access in order to solve user authentication failure problems by the authorized user when behavioral characteristics are used for multi-factor authentication. It enables for the authorized user to use the stored information in the information system even though the user fails to authenticate behavioral characteristics by granting the user differentiated authority.

The purpose of this study is to find the effect of attitude for Computer-Mediated Communication(CMC) on the degree of social presence and satisfaction in the SNS based real-time discussion. The results of this study were summarized as followed : First, the attitude for CMC affects the social presence degree in the SNS based real-time discussion(β=.37, p<.05). Second, the attitude for CMC affects the discussion satisfaction degree in the SNS based real-time discussion(β=.38, p<.05). The result of this research implicated that the effective social presence and satisfaction was depending on attitude for CMC in the SNS based real-time discussion.

Recently light weight notebook that has good performance produced commonly. In order to reduce the size of a laptop keyboard, the keyboard arrangement is important but 108 key used in the must computer are difficult to reduce the size. As a result, almost all lightweight notebooks and net books in the case of produce light weight, drastically the existing 108-key keyboard with numeric keypad keys removed to reduce the size and weight. In this paper, users who were having discomfort of using the keyboards of size reduced in lightweight notebooks and netbooks, to use easy as before solved by Android smartphones. Proposed a virtual numeric keypad system, which is implement on Android smartphone and a laptop connected with a wireless network.

A leakage in a waterworks pipe not only does it cause an suspension of water supply but a high cost may be involved in order to restore the leakage and cause other inconveniences. Even if a repairman arrives to restore the leakage, the individual might be unable to find the exact location of the leakage and also experience other problems. In this paper, we designed a real time data push alert transfer module that is both stable and effective through the use of GCM services by Google to make sure that the supervisors at the waterworks pipe accident site are able to respond quickly and receive real time information on the accident. A real time field information warning system has been developed through the use of augmented reality technique for confirming in real time the information of the accident site.

This research is an implementation of a shooting game that shooting down the opposite term's fighter plane by firing bullets while moving our term's fighter plane. The opposite team’s fighter plane is created randomly and perish when it gets out of the realm. There are two offense strategies . The first one is attacking while moving oneself’s plane. The other strategy is that the player transfer his plane but offense is conducted by genetic algorithms. The player can move their plane in 3 ways: left, right, and stop. 100 opposite fighter planes are created randomly. The planes gotten out of the realm is excluded. The number of shot down plane in the realm and accuracy rate was evaluated. As a result, satisfied result was shown in second experiment-applying genetic algorithms.

With the increasing demand to deliver high-quality software, more accurate software reliability models and software cost models are required to estimate the optimal software release time and the cost of testing efforts. In this study, reliability software cost model considering intensity function based on life distribution from the process of software product testing was studied. The comparison problem of log power intensity function that is widely used in the field of reliability, reliability growth model, was presented. The software failure pattern was used infinite failure non-homogeneous Poisson process model, the parameters estimation using maximum likelihood estimation was conducted. For analysis of software cost model considering intensity function, in this research, software developers to identify software development cost some extent be able to help. In this study, software cost model, using the infinite non-homogeneous Poisson process(NHPP) failure, more software efficiently optimum delivery times can be predicted. The proposed model is the total number of defects in software release period after the operational software and software to be discovered during maintenance and the defects are not found in all software users should assume that. It's a real step error detection and error correction cost of removing all of the remaining operational steps to eliminate the error is lower than the cost increases, the operating time can be seen as costs increase. Therefore, the optimal discharge time of the software can be realistically predict beforehand.

In this paper, the rectangular microstrip patch antenna for receiving global location satellite signal is designed, and its performance and characteristics are analyzed. The antenna is composed of a squared patch antenna mounted on the substrate with the ground plane. The patch antenna is designed to match the frequency of the global location satellite signal. Right-handed circularly polarized wave will be radiated. For the simple fabrication, microstrip line feeding is selected. Using the antenna simulation tool, we can get the analytic results of reflection coefficient, VSWR and radiation pattern and then they will be compared to the measured results.