• Journal of Advanced Navigation Technology
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• v.14 no.2
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• pp.198-205
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• 2010

Any user in Ubiquitous environments have to be able to access networks in anywhere and anytime. Thus interests and researches are increasing. In this paper, we propose an interface selection scheme that adaptively utilizes a proper interface, as the wireless channel condition changes, instead of utilizing only one interface while the node is in move. The proposed scheme can determine which interface would be the most proper one by measuring data rate, packet error rate (PER), and end-to-end delay of each interface. From the simulation results, it is verified that the proposed scheme is able to enhance packet transmission about 20% better.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.21 no.10
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• pp.1999-2007
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• 2017

In this paper, we implement a multi-band network selection (MNS) system based on Linux operating system which determines the optimal communication link for given network conditions among the available LTE, very high frequency (VHF), and high frequency (HF). The implemented software consists of a network interface, an MNS server, and a user GUI. We perform indoor test to verify the function of the implemented MNS system using two sets of MNS system. To this end, two types of VHF communication links that follow ITU-R M.1842-1 Annex 1 and Annex 4 are emulated in software. In addition, the HF transmission (reception) port of one MNS is directly connected to the HF reception (transmission) port of another MNS. We demonstrate through indoor tests that the implemented MNS system can support seamless maritime communication service in spite of artificial disconnection or re-connection of LTE, VHFs, and HF. The implemented MNS system is applicable to various maritime communication services including e-navigation.

• Journal of KIISE:Information Networking
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• v.36 no.3
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• pp.163-172
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• 2009

Various terminals equipped with multiple interfaces may receive services from wireless networks when they pass through the overlaid heterogeneous networks, and thus the vertical handovers across the wireless networks increases, which will become a big problem in the network resource management. This problem can be efficiently solved by common radio resource management (CRRM). In this paper, we propose two operation algorithms based on network selection jointly with vertical handover as the key CRRM strategies. When a new user tries to get services, the CRRM can choose the best target network according to the proposed Integrated Network Selection Algorithm. When the network cannot satisfy the request from the new users, the proposed Integrated Vertical Handover Algorithm moves existing users to neighborhood networks to accommodate new users. The performance of the proposed algorithms has been validated through extensive simulations.

• Proceedings of the Korean Information Science Society Conference
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• 2007.06a
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• pp.67-68
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• 2007

• Proceedings of the Korean Information Science Society Conference
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• 2012.06a
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• pp.83-85
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• 2012

최근 스마트폰과 같은 모바일 단말기는 데이터 통신을 위해 3G, WiFi, WiBro, LTE 와 같은 다수의 네트워크 인터페이스를 가지고 있다. 또한 이와 같은 모바일 단말기는 대부분 배터리로 동작하기 때문에 에너지 효율성은 매우 중요한 요소이다. 따라서 해당 단말이 통신을 할 때, 주변 네트워크 환경에 따라 에너지, 통신비용 등을 고려하여 최적의 네트워크를 선택하여 사용할 수 있다. 이 때 주변 네트워크 환경에 따라 최적의 네트워크 인터페이스를 탐색하고 선택하는 것은 사용자의 명시적인 선택이나 주기적인 탐색 방법 등이 사용될 수 있다. 본 논문에서는 네트워크 탐색 주기에 따른 다중 네트워크 인터페이스 단말기의 에너지 효율성을 분석하고 효율적으로 네트워크 인터페이스를 선택하는 미들웨어의 프로토타입을 구현하고 평가하였다.

• The Journal of Korea Robotics Society
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• v.1 no.1
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• pp.58-65
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• 2006

The emotional interface is essential technology for the robot to provide the proper service to the user. In this research, we developed emotional components for the service robot such as a neural network based facial expression recognizer, emotion expression technologies based on 3D graphical face expression and joints movements, considering a user's reaction, behavior selection technology for emotion expression. We used our humanoid robots, AMI and AMIET as the test-beds of our emotional interface. We researched on the emotional interaction between a service robot and a user by integrating the developed technologies. Emotional interface technology for the service robot, enhance the performance of friendly interaction to the service robot, to increase the diversity of the service and the value-added of the robot for human. and it elevates the market growth and also contribute to the popularization of the robot. The emotional interface technology can enhance the performance of friendly interaction of the service robot. This technology can also increase the diversity of the service and the value-added of the robot for human. and it can elevate the market growth and also contribute to the popularization of the robot.

• Proceedings of the IEEK Conference
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• 2004.08c
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• pp.671-674
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• 2004

We propose accurate classification method of EEG signals during mental tasks. In the experimental task, the tasks of subjects show 3 major measurements; there are mathematical tasks, color decision tasks, and Chinese phrase tasks. The classifier implemented for this work is a feed-forward neural network that trained with the error back-propagation algorithm. The new BCI system is proposed by using neural network. In this system, tr e architecture of the neural network is composed of three layers with a feed-forward network, which implements the error back propagation-learning algorithm. By applying this algorithm to 4 subjects, we achieved $95{\%}$ classification rates. The results for BCI mathematical task experiments show performance better than those of the Chinese phrase tasks. The selection time of each task depends on the mental task of subjects. We expect that the proposed detection method can be a basic technology for brain-computer interface by combining with left/right hand movement or yes/no discrimination methods.

• Journal of the Korea Society of Computer and Information
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• v.26 no.11
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• pp.41-49
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• 2021

All application programs, including malware, call the Application Programming Interface (API) upon execution. Recently, using those characteristics, attempts to detect and classify malware based on API Call information have been actively studied. However, datasets containing API Call information require a large amount of computational cost and processing time. In addition, information that does not significantly affect the classification of malware may affect the classification accuracy of the learning model. Therefore, in this paper, we propose a method of extracting a essential feature set after reducing the dimensionality of API Call information by applying various feature selection methods. We used CICAndMal2020, a recently announced Android malware dataset, for the experiment. After extracting the essential feature set through various feature selection methods, Android malware classification was conducted using CNN (Convolutional Neural Network) and the results were analyzed. The results showed that the selected feature set or weight priority varies according to the feature selection methods. And, in the case of binary classification, malware was classified with 97% accuracy even if the feature set was reduced to 15% of the total size. In the case of multiclass classification, an average accuracy of 83% was achieved while reducing the feature set to 8% of the total size.

• Journal of the Korea Society of Computer and Information
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• v.18 no.1
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• pp.83-91
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• 2013

As humans perform many tasks using computers, HCI(Human-Computer Interaction) has received much attention these days. One objective of HCI research is to propose how to design more consistent systems. In order to evaluate the consistency of HCI devices from the user's perspective, several models such as TAG(Task Action Grammar), GOMS(Goals-Operators-Methods-Selection Rule), and GTN(General Transition Network) have been developed. TAG specifies actions to perform tasks in terms of rule schema. It has been verified that the less the number of rule schema is, the better users perform the tasks due to assumably higher consistency. This paper hypothesizes that the consistency of systems depends not only on the number of rule schema but also on the distances between rule schema. That is, the closer the rule schema are, the easier it is to acquire the whole set of rule schema. An experiment supported this hypothesis. Therefore, distances between rule schema should be considered as well as the number of rule schema when designing systems.

• Korean Institute of Interior Design Journal
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• no.34
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• pp.157-164
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• 2002

Online business these days prone to approach their costumers with improved module and various interface via Internet. This is more than just an act of providing enhancement, but a mean of finding out the customer's demand by enlarging their selection. This, however, is related to the bits per second of supplemental service network.For example, supplemental services that were not possible in the 56K modem era are now possible due to the information super highway network. To grope for new means of approaching, the best way will be by developing media that will collect customer's demands. Until now, customer's demands were evaluated by miniatures of apartment building, model houses or rendered images produced by 3D graphic softwares and pictures. Analyses were not available until evaluation were produced.Nowadays, utilizing the advanced Internet interface tools and various new media, customers are sought before the construction thus various studies to full fill the customer's demands are in process. This study is on development of a virtual module utilizing activated web environment. Analysis modules repeating the changes in customers are expected to deliver us a new trend.