• Journal of the Korea Institute of Information and Communication Engineering
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• v.26 no.8
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• pp.1255-1258
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• 2022

Recently, immersive VR/AR contents have actively increased, and various services related to VR/AR allow users to experience remote places. For example, if failure situations occur frequently in factory of the remote site, mixed reality (MR) with a synthetic virtual human expert in reconstructed remote location can help immediate maintenance task with interaction between the operator and the virtual expert. In this paper, we present a technique for synthesizing the virtual human after capturing a 360-degree panorama of a remote environment, and analyze the effects to apply a method of guiding virtual human by interaction types. According to this paper, it was shown that co-presence level significantly increased when verbal, facial expression, and non-verbal animation of the virtual human was all expressed.

• Journal of information and communication convergence engineering
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• v.20 no.2
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• pp.73-78
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• 2022

Based on experimental measurements conducted on many different practical wireless communication systems, ambient noise has been shown to be decidedly non-Gaussian owing to impulsive phenomena. However, most multiuser detection techniques proposed thus far have considered Gaussian noise only. They may therefore suffer from a considerable performance loss in the presence of impulsive ambient noise. In this paper, we consider a large-scale multiuser multiple-input multiple-output system in the presence of non-Gaussian noise and propose a genetic algorithm (GA) based detector for large-dimensional multiuser signal detection. The proposed algorithm is more robust than linear multi-user detectors for non-Gaussian noise because it uses a multi-directional search to manipulate and maintain a population of potential solutions. Meanwhile, the proposed GA-based algorithm has a comparable complexity because it does not require any complicated computations (e.g., a matrix inverse or derivation). The simulation results show that the GA offers a performance gain over the linear minimum mean square error algorithm for both non-Gaussian and Gaussian noise.

• Proceedings of the Korean Society of Computer Information Conference
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• 2021.01a
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• pp.303-304
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• 2021

본 연구에서는 비대면 환경에서 실재감이 학습성과에 미치는 영향을 분석하였다. 전문대학의 프로그래밍 수업을 수강하는 427명의 학생을 대상으로 교수실재감, 인지적 실재감, 감성적 실재감과 만족도, 학습지속의 향의 관계를 분석하였다. 연구 결과, 만족도에는 교수실재감과 인지적 실재감이, 학습지속의향에는 교수실재감, 인지적 실재감, 감성적 실재감이 영향을 미치는 것으로 나타났다. 연구결과에 기초하여 비대면 환경의 프로그래밍 수업에 대한 설계 및 운영전략을 시사하였다.

• Journal of the Korean Statistical Society
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• v.22 no.1
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• pp.1-12
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• 1993

An approach to make the information bound sharper in median-unbiased estimation, based on an analogue of the Cramer-Rao inequality developed by Sung et al. (1990), is introduced for continuous densities with a nuisance parameter by considering information quantities contained both in the parametric function of interest and in the nuisance parameter in a linear fashion. This approach is comparable to that of improving the information bound in mean-unbiased estimation for the case of two unknown parameters. Computation of an optimal weight corresponding to the nuisance parameter is also considered.

• Journal of Korean Library and Information Science Society
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• v.28
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• pp.479-503
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• 1998

This paper examines the effects of the Internet on the librarianship and how the changing roles of libraries and librarians are reshaping the way they serve the users in the information age. Each area of operations and services in a so-called Digital/Electronic Library, which is a phenomenon occurring now not sometime later in the future, is reviewed. The importance of keeping in mind the library' main mission of providing a service, i.e. access to information, is stressed as the pivotal point of librarianship in this global society influenced by the presence of the Internet.

• Fashion & Textile Research Journal
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• v.22 no.3
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• pp.310-322
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• 2020

This study investigated the classification and characteristics of augmented reality (AR) content of fashion brands. The AR contents of fashion brands were classified according to user participation space and content delivery method. Based on these types, eight case studies were conducted, along with a discussion of AR characteristics in terms of presence, interactivity, and immersion. The results showed that AR content could be divided into four types: offline visit-external information type, offline visit-internal experience type, online utilization-external information type, and online utilization-internal experience type. It was also found that there were differences in characteristics for each type of AR content. First, the offline visit-external information type requires various new content that can provide entertainment immersion to users. Second, the offline visit-internal experience type requires a powerful inducement for users to visit a specific space providing AR content and to participate in augmented environments. Third, the online utilization-external information type needs a series of AR content that can consistently incite users' curiosity about brands and products. Fourth, the online utilization-internal experience type needs effective content to improve users' shopping experience with the virtual fitting of fashion accessories, such as eyewear, hats, jewelry, and watches. Accordingly, fashion companies should create contents that can provide appropriate presence, interactivity, and immersion by AR type.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.17 no.3
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• pp.561-566
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• 2013

In this paper, android phone information push system based on the XMPP protocol is proposed. For this, we implement a XMPP(eXtensible Message and Presence Protocol) based instant message system in C/S network environment by using Java language and eclipse device. This system not only allows sending and receiving messages from the PC server to mobile phone client, but also enables the expansion into the smack package of an android phone. Thus, this system shown, in this paper has the better performance in transmission and transfer speed than those of the basic XMPP protocol system.

• KSII Transactions on Internet and Information Systems (TIIS)
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• v.9 no.10
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• pp.4204-4222
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• 2015

Cloud is the latest buzz word in the internet community among developers, consumers and security researchers. There have been many attacks on the cloud in the recent past where the services got interrupted and consumer privacy has been compromised. Denial of Service (DoS) attacks effect the service availability to the genuine user. Customers are paying to use the cloud, so enhancing the availability of services is a paramount task for the service provider. In the presence of DoS attacks, the availability is reduced drastically. Such attacks must be detected and prevented as early as possible and the power of computational approaches can be used to do so. In the literature, machine learning techniques have been used to detect the presence of attacks. In this paper, a novel approach is proposed, where intelligent rule based feature selection and classification are performed for DoS attack detection in the cloud. The performance of the proposed system has been evaluated on an experimental cloud set up with real time DoS tools. It was observed that the proposed system achieved an accuracy of 98.46% on the experimental data for 10,000 instances with 10 fold cross-validation. By using this methodology, the service providers will be able to provide a more secure cloud environment to the customers.

• KSII Transactions on Internet and Information Systems (TIIS)
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• v.14 no.9
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• pp.3639-3662
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• 2020

The network capability to accomplish its functions in a timely fashion under failures and attacks is known as survivability. Ad hoc routing protocols have been studied and extended to various domains, such as Intelligent Transport Systems (ITSs), Unmanned Aerial Vehicles (UAVs), underwater acoustic networks, and Internet of Things (IoT) focusing on different aspects, such as security, QoS, energy. The existing solutions proposed in this domain incur substantial overhead and eventually become burden on the network, especially when there are fewer attacks or no attack at all. There is a need that the effectiveness of these routing protocols be analyzed in the presence of Denial of Service (DoS) attacks without any intrusion detection or prevention system. This will enable us to establish and identify the inherently stable routing protocols that are capable to survive longer in the presence of these attacks. This work presents a DoS attack case study to perform theoretical analysis of survivability on node and network level in the presence of DoS attacks. We evaluate the performance of reactive and proactive routing protocols and analyse their survivability. For experimentation, we use NS-2 simulator without detection or prevention capabilities. Results show that proactive protocols perform better in terms of throughput, overhead and packet drop.

• Journal of Korean Academy of Nursing
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• v.42 no.3
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• pp.333-341
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• 2012

Purpose: The purpose of this study was to test whether pre-operative visual information and parental presence had positive effects on anxiety, delirium, and pain in pediatric patients who awoke from general anesthesia in a post-surgical stage. Methods: This study used a non equivalent control-group post test design (n=76). Independent variables were provision of pre-operative visual information and parental presence for post-surgical pediatric patients in PACU (post anesthesia care unit). Dependent variables were anxiety, delirium, and pain in the pediatric patients measured three times at 10 minute intervals after extubation in the PACU. Measurements included Numerical Rating Scale for assessing state anxiety, Pediatric Anesthesia Emergence Delirium Scale by Sikich & Lerman (2004) for delirium, and Objective Pain Scale by Broadman, Rice & Hannallah (1988) for pain. Results: Experimental group showed significantly decreased state anxiety at time points-10, 20, and 30 minutes after extubation. Delirium was significantly lower at 10 minutes and 30 minutes after extubation in the experimental group. Pain was significantly lower at 10 minutes after extubation in the experimental group. Conclusion: The results of this study suggest that this intervention can be a safe pre-operative nursing intervention for post-surgical pediatric patients at PACU.