• Journal of Digital Convergence
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• v.18 no.6
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• pp.451-457
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• 2020

In this study, the degree of motion sickness displayed according to actions in virtual reality is measured based on the SSQ tool, a measuring tool, and factors and symptoms affecting cyber motion sickness are investigated through comparative analysis. In the first experiment, the operation method experiment, the simple operation method is measured to be highly affected by the Nausea factor. As symptoms of this, nausea, burp and headache symptoms were developed. In the second experiment, the larger the body rotation radius, the higher the motion sickness was measured, and the greater the influence of Nausea factors. Symptoms of this were the symptoms of burping, headaches, and a full head. In the third experiment, the physical mobility experiment, motion sickness was measured highly in the non-action controller. It was measured to be greatly affected by the Nausea factor. Symptoms of this include fever, headache, and a full head. Through this study, we found that the more fixed and simple the body is operated in virtual reality, the more sensitive the user is to motion sickness, and the larger the radius of rotation, the more sensitive it is to motion sickness. This study is meaningful in identifying factors and symptoms that affect motion sickness and VR manipulation, and is expected to be used by developers in the future to recognize the degree and symptoms of motion sickness of users and to develop content.

• Journal of The Korean Association For Science Education
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• v.24 no.2
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• pp.277-286
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• 2004

This study investigated the types and frequencies of student-student questioning (SSQ) in a small group activities, 5 in one group or 2 in one group, during school experiments. Five girls of seventh grade were observed during school experiments and interviewed afterward. Between students, information-type questions were asked more frequently than thought-type questions. Most of the information-type questions were procedural ones and most of the thought-type questions were comprehension ones. However, thought-type questions did not make further discussion in the activities. The rate of answers in the case of 2 in one group was higher than that of 5 in one group. Moreover, the similar tendency was found when we investigated the rate of helpful question-answers. In a pair, lower achiever usually asked questions, not answered as much as in 5 in one group, and higher achiever answered. The frequency of SSQ in a pair was relatively low when there was a big difference of science achievements between pair members. In conclusion, information-type questions were asked more frequently than thought-type questions during school experiments and the rate of helpful question-answers was higher when group members was fewer.

• Journal of the Korean Academy of Child and Adolescent Psychiatry
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• v.4 no.1
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• pp.106-113
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• 1993

Using a reliable assessment procedure and according to the severity of hyperactivity, thirty-six clinic-referred outpatients, 6-12 years of age, were given a diagnosis of Attention Deficit Disorder with Hyperactivity(ADD+H) or without Hyperactivity(ADD-H). Comparisons of behavioral measurement by Conners Rating Scale(CRS) and Home/School Situations Questionnaire(HSQ/SSQ) revealed that the children with ADD+H displayed more pervasive behavior problems at home and school than the children with ADD-H. Also the children with ADD+H were more likely to be delinquent and aggressive compared to the children with ADD-H when using the Child Behavior Check-list(CBCL) for parents Hyperactivity symptom in ADHD is highly correlated with aggression scale on CBCL These finding suggest that ADD+H and ADD-H may differ in clinical disease entity.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.29 no.2B
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• pp.279-288
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• 2004

Rapidly emerging P2P(Peer to Peer) applications generate very bursty traffic, which gives a lot of burden to network, and the amount of such traffic is increasing rapidly. Thus it is becoming more important to understand the characteristics of such traffic and reflect it when we design and analyze the network. To do that we measured the traffic in a campus network and present flow statistics and traffic models of the measured traffic, and compare them with those of the web traffic. The results indicate that P2P traffic is much burstier than web traffic and as a result it negatively affects network performance. We modeled P2P traffic using self-similar traffic model to predict packet delay and loss occurred in network which are very important to evaluate network performance. We also predict queue length distribution and loss probability in SSQ(Single Sewer Queue). To assess accuracy of traffic model, we compare the SSQ statistics of traffic models with that of the traffic trace. The results show that self-similar traffic models we use can predict P2P traffic behavior in network precisely. It is expected that the traffic models we derived can be used when we design network capacity and predict network performance and QoS of the P2P applications.

• Science of Emotion and Sensibility
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• v.26 no.4
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• pp.103-114
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• 2023

Augmented reality (AR) and virtual reality (VR) differ fundamentally, with AR overlaying computer-generated information onto the real world in a nonimmersive way. Despite extensive research on cybersickness in VR, its occurrence in AR has received less attention (Vovk et al., 2018). This study examines cybersickness and discomfort associated with AR usage, focusing on the impact of content intensity and exposure time. Participants viewed 30-minute racing simulation game clips through AR equipment, varying in racing speed to alter content intensity. Cybersickness was assessed subjectively using the Simulator sickness questionnaire (SSQ; Kennedy et al., 1993). Findings revealed a progressive increase in cybersickness with longer exposure, persisting even after removing the AR equipment. Contrarily, content intensity did not significantly influence cybersickness levels. Analysis of the SSQ subscales revealed higher oculomotor (O) scores compared to nausea (N) and disorientation (D), suggesting that discomfort primarily stemmed from oculomotor strain. The study highlights distinct differences in user experience between AR and VR, specifically in subjective responses.

• Journal of Korea Multimedia Society
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• v.6 no.7
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• pp.1149-1158
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• 2003

Content adaptive watermark embedding algorithm using a stochastic image model in the multiwavelet transform is proposed in this paper. A watermark is embedded into the perceptually significant coefficients (PSCs) of each subband using multiwavelet transform. The PSCs in high frequency subband are selected by SSQ, that is, by setting the thresholds as the one half of the largest coefficient in each subband. The perceptual model is applied with a stochastic approach based on noise visibility function (NVF) that has local image properties for watermark embedding. This model uses stationary Generalized Gaussian model characteristic because watermark has noise properties. The watermark estimation use shape parameter and variance of subband region. it is derive content adaptive criteria according to edge and texture, and flat region. The experiment results of the proposed watermark embedding method based on multiwavelet transform techniques were found to be excellent invisibility and robustness.

• Journal of Korea Multimedia Society
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• v.6 no.3
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• pp.508-517
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• 2003

This paper presents perceptual model with a stochastic multiresolution characteristic that can be applied with watermark embedding in the biorthogonal wavelet domain. The perceptual model with adaptive watermarking algorithm embeds at the texture and edge region for more strongly embedded watermark by the SSQ. The watermark embedding is based on the computation of a NVF that has local image properties. This method uses non- stationary Gaussian and stationary Generalized Gaussian models because watermark has noise properties. The particularities of embedding in the stationary GG model use shape parameter and variance of each subband regions in multiresolution. To estimate the shape parameter, we use a moment matching method. Non-stationary Gaussian model uses the local mean and variance of each subband. The experiment results of simulation were found to be excellent invisibility and robustness. Experiments of such distortion are executed by Stirmark 3.1 benchmark test.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.26 no.12A
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• pp.2100-2108
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• 2001

A digital image watermarking algorithm is proposed that uses human visual system (HVS) and discrete wavelet transform (DWT). In this algorithm, an image is decomposed into four-level by DWT which reveals the characteristics of the human eyes and watermark is embedded into DWT coefficients using HVS. For robustness, the lowest level subbands which represent the highest frequency component are excluded in watermark embedding step and watermark is embedded into the perceptually significant coefficients (PSCs) of the rest subbands. PSCs of the baseband are selected according to the amplitude of the coefficients and PSCs of the high frequency subbands are selected by successive subband quantization (SSQ). Watermark is embedded into the PSCs of the baseband and high frequency subbands by Weber\`s law and spatial masking effect, respectively, for the invisibility and robustness. We tested the performance of the proposed algorithm compared with the conventional watermarking algorithm by computer simulation. Experimental results show that the proposed watermarking algorithm produces a better invisibility and robustness than the conventional algorithm.

• Journal of the Korea Computer Graphics Society
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• v.27 no.3
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• pp.43-53
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• 2021

This paper presents an interactive wind system that generates artificial winds in a virtual reality (VR) environment according to online user inputs from a steering wheel and an acceleration pedal. Our system is composed of a head-mounted display (HMD) and three electric fans to make the user sense touch from the winds blowing from three different directions in a racing car VR application. To evaluate the effectiveness of the winds for reducing VR cybersickness, we employ the simulator sickness questionnaire (SSQ), which is one of the most common measures for cybersickness. We conducted experiments on 13 subjects for the racing car contents first with the winds and then without them or vice versa. Our results showed that the VR contents with the artificial winds clearly reduce cybersickness while providing a positive user experience.

• The Journal of Internal Korean Medicine
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• v.40 no.2
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• pp.192-200
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• 2019

Introduction: The aim of this study is to report the effect of traditional Korean medical treatment on fibromyalgia. Case presentation: A patient with fibromyalgia was treated with acupuncture, pharmacopuncture (Bee venom, Hwangryunhaedok-tang), cupping therapy, moxibustion therapy and herbal medicine for 37 days. To reduce the patient's symptoms, we provided herbal medicine three times a day, as well as acupuncture, pharmacopuncture, cupping therapy and moxibustion therapy once a day for 37 days. To evaluate the results of this treatment, we used the Numeral Rating Scale (NRS), Score of Sleeping Quality (SSQ) and Fibromyalgia Impact Questionnaire (FIQ). After treatment, the patient showed that pain was reduced, the score of NRS was improved, FIQ improved from 91 to 69 and SSQ improved from 3 to 1. No adverse reaction was noted. Conclusion: According to the result, traditional Korean medical treatment can be effective and safe for the treatment of fibromyalgia.