• Journal of The Korean Association For Science Education
• /
• v.29 no.6
• /
• pp.730-740
• /
• 2009

The purpose of this study was to investigate secondary science teachers' brain activation and functional connectivity during scientific observation on the biological phenomena. Twenty six right-handed healthy science teachers volunteered to be in the present study. To investigate science teachers' brain activities during the tasks, 3.0T fMRI system with block design was used to measure BOLD signals in their brains. The SPM2 software package was applied to analyze the acquired initial image data from the fMRI system. The results have shown that the left inferior frontal gyrus, the bilateral superior parietal lobule, the left inferior parietal lobule, the left precuneus, the left superior occipital gyrus, the right middle occipital gyrus, the right precuneus, the left inferior occipital gyrus and bilateral fusiform gyrus were significantly activated during participants' scientific observation. The network model consisted of eleven nodes (ROIs) and its ten connections. These results suggested the notion that scientific observation needs a connective cooperation among several brain regions associated with observing over just a sensory receiving process.

• Korean Journal of Cognitive Science
• /
• v.10 no.1
• /
• pp.67-78
• /
• 1999

Information providers on WWW have been rapidly increasing, and they provide a vast amount of information in various fields, Because of this reason, it becomes hard for users to get the information they want. Although there are several search engines that help users with the keyword matching methods, it is not easy to find suitable keywords. In order to solve these problems with a specific domain, we propose an intelligent information agent(HHA-la : HongIk Information Agent) that converts user's q queries to forms including related domain words in order to represent user's intention as much as it can and provides the necessary information of the domain to users. HHA-la h has an ontological knowledge base of animal domain, supplies necessary information for queries from users and other agents, and provides relevant web page information. One of system components is a WebDB which indexes web pages relevant to the animal domain. The system also supplies new operators by which users can represent their thought more clearly, and has a learning mechanism using accumulated results and user feedback to behave more intelligently, We implement the system and show the effectiveness of the information agent by presenting experiment results in this paper.

• Journal of Broadcast Engineering
• /
• v.24 no.1
• /
• pp.67-76
• /
• 2019

In this paper, we propose an efficient object classification method based on semantic segmentation for multi-labeled image data. In addition to various pixel unit information and processing techniques such as color information, contour, contrast, and saturation included in image data, a detailed region in which each object is located is extracted as a meaningful unit and the experiment is conducted to reflect the result in the inference. We use a neural network that has been proven to perform well in image classification to understand which object is located where image data containing various class objects are located. Based on these researches, we aim to provide artificial intelligence services that can classify real-time detailed areas of complex images containing various objects in the future.

• The Journal of Korean Institute of Communications and Information Sciences
• /
• v.32 no.2A
• /
• pp.203-212
• /
• 2007

An advanced vehicle safety system can be constructed by exchanging danger-related information ,such as urgency stop, traffic accident, obstacle, and car trouble, among the vehicles. However, because network topology changes rapidly and frequently due to the mobility of vehicles, it is impossible to configure the network for information forwarding in this environment. In the most of vehicle safety communication applications, an emergency message is propagated in a form of broadcasting. The simple broadcasting causes a lot of problems in terms of efficiency due to multi-hop area and radio collision problem. This paper proposes a method of selective message forwarding with stem and branch structure for propagating the emergency messages. However, the proposed method raise the efficiency of message transmission with the selective forwarding based on the priority assignment as its location. We analyze and evaluate the performance by comparing the proposed scheme with other schemes that are presented in the paper.

• Journal of the Korean Society for Railway
• /
• v.10 no.6
• /
• pp.758-765
• /
• 2007

In this paper, we propose an efficient seamless handoff scheme to minimize packet loss and unnecessary packets on the Internet using the peculiar mobility characteristics of public vehicles such as trains. MR (Mobile Router) in a train visits each AR (Access Router) in the fixed order. As the MR detects reachability to the NAR (Next Access Router) on the new link, the PAR (Previous Access Router) can directly deliver packets from MR's HA (Home Agent) to the NAR according to the HML (Handoff Mobile router List). Then. the NAR buffers them until the MR finishes L3 (Layer 3) handoff procedure with the NAR. Therefore, our scheme can support a seamless handoff without the packet loss and unnecessary packets on the Internet. The result of our performance evaluation has shown that the proposed scheme could provide excellent performance, compared with the NEMO basic support protocol and the Bi-casting protocol.

• Information Systems Review
• /
• v.22 no.2
• /
• pp.1-24
• /
• 2020

Cloud computing technology is expanding its services to individual consumers through storage and applications. This study aims to compare the predisposing factors that affect the perceived value and the intention to use between users who have used or experienced services and those who have never experienced services from the perspective of benefit and sacrifice based on the value-based acceptance model. The results showed that the sacrifice factor (perceived cost) had a significant effect on perceived value and perceived value had a significant effect on intention to use, but showed a difference in perceived benefit. Perceived usefulness, ubiquity, and network effects had significant impact for experienced users' perceived value, but for inexperienced users, ubiquity did not have significant impact. In addition, usefulness was the most significant factor for experienced users while network effect was the same for inexperienced users. The results of this study suggest that consumers' intention to use personal cloud service is evaluated as a benefit and sacrifice point and a new attempt to re-examine the role of previous experience.

• Electronics and Telecommunications Trends
• /
• v.17 no.5 s.77
• /
• pp.55-67
• /
• 2002

최근 인터넷 트래픽이 폭증하고 서비스 품질에 대한 요구가 증가함에 따라 백본과 가입자 망에 대하여 집중적인 투자가 이루어져 빠른 속도로 고속화되고 있으나, 메트로 영역에 대한 투자가 상대적으로 적어 메트로 망이 전체 네트워크에서 병목이 되는 결과를 초래하고 있다. 메트로 망을 고속화하기 위해서는 초기 설치비가 저렴하고 확장이 용이하여야 할 뿐만 아니라 사용자가 요구하는 대역폭을 신뢰성있게 제공할 수 있는 망 기술이 요구된다. 이러한 요구에 따라 충분한 대역폭을 저렴하고 신뢰성있게 제공하기 위한 RPR(Resilient Packet Ring) 기술이 제안되어 표준화되고 있다. 본 고에서는 향후 메트로 망의 링 기술로 부각되고 있는 RPR에 대하여 기술적 특징, 표준화 동향 및 적용 방안을 살펴보고 향후 기술을 전망해 본다.

• Journal of the Korea Institute of Information Security & Cryptology
• /
• v.16 no.1
• /
• pp.97-104
• /
• 2006

For successfully deploying many multicast service in the mobile environment, security infrastructures must be developed that manage the keys needed to provide access control to content. In this paper, we propose two methods for designing the key management scheme for the mobile multicast environment. The proposed schemes match the key management tree to the mobile multicast environment for localizing the delivery of he rekeying messages, reducing the communication costs, and solving the handoff problem in wireless region.

• Journal of the Korea Academia-Industrial cooperation Society
• /
• v.10 no.11
• /
• pp.3176-3182
• /
• 2009

The PBNM on MANET is being researched to ensure the reliability and efficiency between mobile nodes. Therefore, it is essential to determine the cluster effectively which will perceive the movements of nodes and distribute the policies. In PBNM mechanism, to determine the node cluster for PDP and manage PEP nodes, Active PDP Discovery Protocol is proposed as a mechanism which is more efficient than preexistent techniques. While k-hop cluster selects the PEP nodes which PDP node manages, Active PDP Discovery actively selects the PDP node among the moving PEP node. This method prevents orphan nodes that are not connected to PDP and reduces continual broadcasting messages. This paper implements Active PDP Discovery which determines cluster in the real networks and analyzes its capability, expanding COPS-PR to detect the movement of nodes and adding MNL to PDP node.

• Korean Journal of Construction Engineering and Management
• /
• v.11 no.4
• /
• pp.68-79
• /
• 2010

During the last two decades, several tele-operated and machine-vision-assisted systems have been developed in construction and maintenance area such as pavement crack sealing, sewer pipe rehabilitation, and excavation. In developing such tele-operated and machine-vision-assisted systems, trajectory plans are very important tasks for optimal motions of robots whether their environments are structured or unstructured. This paper presents an optimal trajectory planning algorithm used for a machine-vision-assisted automatic pavement crack sealing system. In this paper, the performance of the proposed optimal trajectory planning algorithm is compared with the greedy trajectory plans which are used in previously developed pavement crack sealing systems. The comparison is based on computational cost versus overall gains in crack sealing efficiency. Finally, it is concluded that the proposed algorithm plays an important role in productivity improvement of the automatic pavement crack sealing system developed.