• Journal of the Korea Institute of Information and Communication Engineering
• /
• v.24 no.7
• /
• pp.827-833
• /
• 2020

In this paper, to reduce the unpaid rate of local governments, the internal data elements affecting the arrears in Water-INFOS are searched through interviews with meter readers in certain local governments. Candidate data affecting arrears from national statistical data were derived. The influence of the independent variable on the dependent variable was sampled by examining the disorder of the dependent variable in the data set called information gain. We also evaluated the higher prediction rates of decision tree and logistic regression using n-fold cross-validation. The results confirmed that the decision tree can find more accurate customer payment patterns than logistic regression. In the process of developing an analysis algorithm model using machine learning, the optimal values of two environmental variables, the minimum number of data and the maximum purity, which directly affect the complexity and accuracy of the decision tree, are derived to improve the accuracy of the algorithm.

• Smart Media Journal
• /
• v.5 no.3
• /
• pp.42-48
• /
• 2016

Recently, most of the modern people used a second mobile device(two degree mobile device). Mobile devices are affecting all areas of human life, consumer electronics, transportation, manufacturing, and finance. On this paper, we propose a model-driven development based interaction model that can be used in the development of mobile payment system, which is the latest buzzword pins of the various application fields of mobile devices Tech (Fin-Tech) sector. Using a model-driven development based models do not depend on the Platforms (PIM), we propose a model for interaction between devices which can be reused when developing mobile billing app. A model-driven development based mobile applications use the reusable of interaction models development program analyzed the bus fees automatic payment application by a beacon.

• Journal of the Korean Institute of Intelligent Systems
• /
• v.16 no.1
• /
• pp.49-54
• /
• 2006

The recent fingerprint recognition system has unstable factors, such as copy of fingerprint patterns and hacking of fingerprint feature point, which mali cause significant system error. Thus, in this research, we used the fingerprint as the main recognition device and then implemented the multi-biometric recognition system in serial using the speech recognition which has been widely used recently. As a multi-biometric recognition system, once the speech is successfully recognized, the fingerprint recognition process is run. In addition, speaker-dependent DTW(Dynamic Time Warping) algorithm is used among existing speech recognition algorithms (VQ, DTW, HMM, NN) for effective real-time process while KSOM (Kohonen Self-Organizing feature Map) algorithm, which is the artificial intelligence method, is applied for the fingerprint recognition system because of its calculation amount. The experiment of multi-biometric recognition system implemented in this research showed 2 to $7\%$ lower FRR (False Rejection Ratio) than single recognition systems using each fingerprints or voice, but zero FAR (False Acceptance Ratio), which is the most important factor in the recognition system. Moreover, there is almost no difference in the recognition time(average 1.5 seconds) comparing with other existing single biometric recognition systems; therefore, it is proved that the multi-biometric recognition system implemented is more efficient security system than single recognition systems based on various experiments.

• Journal of the Korea Institute of Information Security & Cryptology
• /
• v.30 no.5
• /
• pp.771-780
• /
• 2020

QKD(Quantum Key Distribution) is one of the protocols that can make two distant parties safely share secure keys against the threat of quantum computer. Generally, cryptographic applications which are connected to the QKD device have fixed roles as a transmitter and a receiver due to the race condition and complexity of implementation. Because the conventional QKD system is mainly applied to the link encryptor, there are no problems even if the roles of the cryptographic devices are fixed. We propose a new scheme of QKD system and protocol that is easy to extend to the QKD network by eliminating quantum key dependency between cryptographic device and QKD node. The secure keys which are generated by the TRNG(True Random Number Generator) are provided to the cryptographic applications instead of quantum keys. We design an architecture to transmit safely the secure keys using the inbound and outbound quantum keys which are shared between two nodes. In this scheme, since the dependency of shared quantum keys between two QKD nodes is eliminated, all cryptographic applicatons can be a master or a slave depending on who initiates the cryptographic communications.

• Journal of the Korea Society of Computer and Information
• /
• v.14 no.5
• /
• pp.201-209
• /
• 2009

RThe main object of this study is to stipulate the relation between e-learning characteristics and e-learner's scholastic performance through the integrated study model of perspective of educational technology and information technology. Using e-learning system quality, e-learning contents characteristics and interaction as independent variable, e-learner's scholastic performance as dependent variable and learning motivation as mediator, this study has examined the relationship among these variables. Two hundreds and twelve undergraduates in cyber university participated in the survey and filled out questionnaires related to this study. The main results are as followed. First, content's quality, technical quality and the support of school affairs have a significant effect on the e-learner's scholastic performance. Second, Learning motivation plays a partial mediating role in the relationship between e-learning characteristics and e-learner's scholastic performance. The meaningful implication of this study is that to improve e-learner's scholastic performance, we have to offer e-learners more customized various learning plans, learning contents and interaction between e-learners and e-learning systems.

• The KIPS Transactions:PartA
• /
• v.11A no.4
• /
• pp.285-296
• /
• 2004

The rapid progress of IT technologies promoted the foundation to offer users 'Any Time, Any Where, Any Service', and wireless internet services made it possible to use wired internet services while traveling. The previous academic administration management system having migrated from wired to wireless was dependent on mobile equipments' platform because of not being constructed on standard surroundings. And in the aspect of faculty system, course coordinator plays an significant role in building curricula and manage them, and finally counseling students with regard to them. But the course coordinator can't afford to advise students on which fields of their faculty fit them and which courses they have to take. We propose a mobile course coordinator system to help students learn profound courses of their major fields. Also the proposed system is implemented by using JAVA and WIPI technology, so that it is platform-independent. A mobile course coordinator system has an inference engine considering not only course trees which tell informations about the courses in every fields, but also personal courses that students have taken. The inference engine calculates three weights, representing the significance of each course considering every fields, the score of prerequisite courses which a student have taken, and the suitability in which department each student fits. When students apply for taking lectures, a mobile course coordinator system recommends them the most suitable courses. A mobile course coordinator system is able to substitute for the course coordinator who is counseling students. And the students with personal cellular phone are able to keep tracking their courses, and improve their knowledge about major with taking courses which the system's inference engine will advice.

• Journal of the Korean BIBLIA Society for library and Information Science
• /
• v.16 no.2
• /
• pp.139-156
• /
• 2005

In this paper, we design and implement electronic book system providing web-based interface for the ebook. The aim of this study is to optimize the effective reading and management of electronic text for its users(readers and librarians). Advanced functions of the electronic book system are the following: 1) Electronic book system is not dependent to specific software and tool. 2) Electronic book system is able to. minimize images(table, image, icon etc) to improve the meaning and readability of information. 3) Electronic book system is able to reduce the effort for indexing extraction and constructing the table of content. 4) The system is able to collect the user log files that are created during the process of reading ebook from various points of view. 5) When reading, the system uses the DRM through decoding and encoding the ebook.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
• /
• 2008.10a
• /
• pp.320-323
• /
• 2008

Due to the improvement of mobile device capabilities, a demand for various contents service is increasing. But the differences from heterogeneous mobile devices force to develop contents which is dependent on a mobile. To solve this problem, adaptation course that reorganize contents by the device capability is needed. In this course, device description is described using device description language but there are some problems that is absence of device description repository and the way to get device description data. In this paper, I suggest device description acquisition module and define the interfaces to access device description repository that I designed and implemented.

• Journal of the Korea Institute of Information and Communication Engineering
• /
• v.12 no.11
• /
• pp.2091-2096
• /
• 2008

Due to the improvement of mobile device capabilities, a demand for various contents service is increasing. But the differences from heterogeneous mobile devices force to develop contents which is dependent on a mobile. To solve this problem, adaptation course that reorganize contents by the device capability is hooded. In this course, device description is described using device description language but there are some problems that is absence of device description repository and the way to get device description data. In this paper, I suggest device description acquisition module and define the interfaces to access device description repository that I designed and implemented.

• The Journal of the Korea Contents Association
• /
• v.10 no.7
• /
• pp.355-365
• /
• 2010

IT service is becoming a critical business operation in the age of information revolution. In providing IT services internally to other functions of the corporation and externally to other organizations, sharing of knowledge between business people and system people is known to become more and more critical for successful IT services. Purpose of this research is to examine the impact of IT service quality on knowledge sharing activities between IT service providers and users. Theoretical research model, through an extant literature review, is proposed here, consisting of IT service quality, relationship quality(satisfaction, trust and commitment), and the level of knowledge sharing activities. Survey results of 183 users indicates that IT service quality significantly influences commitment through satisfaction and trust, which in turn influences the level of knowledge sharing activities. Also, interestingly, satisfaction and trust do not directly influences the level of knowledge sharing,but indirectly, through commitment.