• The KIPS Transactions:PartD
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• v.15D no.5
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• pp.713-720
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• 2008

Fingerprinting scheme uses digital watermarks to trace originator of unauthorized or pirated copies, however, multiple users may collude and escape identification by creating an average or median of their individually watermarked copies. Previous research works are based on ACC (anti-collusion code) for identifying each user, however, ACC are shown to be resilient to average and median attacks, but not to LCCA and cannot support large number of users. In this paper, we propose a practical SACC (scalable anti-collusion code) scheme and its angular decoding strategy to support a large number of users from basic ACC (anti-collusion code) with LCCA (linear combination collusion attack) robustness. To make a scalable ACC, we designed a scalable extension of ACC codebook using a Gaussian distributed random variable, and embedded the resulting fingerprint using human visual system based watermarking scheme. We experimented with standard test images for colluder identification performance, and our scheme shows good performance over average and median attacks. Our angular decoding strategy shows performance gain over previous decoding scheme on LCCA colluder set identification among large population.

• The Journal of Korean Physical Therapy
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• v.23 no.1
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• pp.21-28
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• 2011

Purpose: The aim of this study was to investigate correlations between the Functional Movement Screen (FMS), pain, and performance ability in professional fencing players. Methods: Fifty-six athletes participated in this study. The pain group included those who had a score on a pain-related Visual Analogue Scale (VAS) of ${\geq}$20 and an Oswestry Disability Index (ODI) score ${\geq}$10). In the non-pain group, these scores were: VAS(<20), ODI(<10). The VAS and ODI were used to measure pain throughout the study. Performance ability included motor function of the lower extremities (as assessed by a Modified Functional Index Questionnaire, MFIQ), dynamic balance (Balance system, BS and Posture med, PM), flexor and extensor muscle strength of the lumbar region was recorded as maximal isometric strength. Results: Among athletes who had pain, 5 of 15(33.33%) showed impaired functional movement. Conversely, only 2 of 41(4.88%) of those who had no pain showed such impairment (FMS ${\leq}$14score). The athletes who had pain and who had an FMS score above 14 (10/56; 17.86%) showed a significantly higher score for extensor muscle strength of the lumbar compared with those with pain and an FMS score below 14 (5/56; 8.93%) were significant correlations between the FMS and pain (r=-0.40 to -0.42, p<0.01), the MFIQ (r=-0.33, p<0.05), dynamic balance (r=-0.27 to -0.40, p<0.05-0.01), muscle strength of the lumbar (r=0.27 to 0.29, p<0.05). Stepwise multiple regression analysis showed that the dynamic balance score (${\beta}{\beta}$=-0.41) had slightly more power in predicting FMS score than pain, motor function of lower extremity, or muscle strength. Conclusion: The FMS was significantly associated with values of pain, motor function of the lower extremities, dynamic balance, and muscle strength of the lumbar. However the FMS appears to lack relevance and reasonable evidence to suggest that it is an acceptable measurement tool for functional movement analysis.

• Tunnel and Underground Space
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• v.17 no.2 s.67
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• pp.128-138
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• 2007

At low in-situ stress, the continuity and distribution of natural fractures in rock mass predominantly control the failure processes. However at high in-situ stress, the failure process are affected and eventually dominated by stress-induced fractures preferentially growing parallel to the excavation boundary. This fracturing is often observed in brittle type of failure such as slabbing or spatting. Recent studies on the stress- or excavation-induced damage of rock revealed its importance especially in a highly stressed regime. In order to evaluate the brittle failure around a deep underground opening, physical model experiments were carried out. For the experiments a new tue triaxial testing system was made. According to visual observation and acoustic emission detection, brittle failure grades were classified under three categories. The test results indicate that where higher horizontal stress, acting perpendicular $(S_{H2})$ and parallel $(S_{H1})$ to the axis of the tunnel respectively, were applied, the failure grade at a constant vertical stress level (Sy) was lowered. The failure initiation stress was also increased with the increasing $S_{H1}\;and\;S_{H2}$. From the multi-variable regression on failure initiation stress and true triaxial stress conditions, $f(S_v,\;S_{H1},\;S_{H2})$ was proposed.

• The KIPS Transactions:PartC
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• v.18C no.4
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• pp.265-278
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• 2011

The objective of this paper is to analyze and characterize end-to-end packet statistics after modeling and simulation of WiFi (IEEE 802.11g) and WiMAX (IEEE 802.16e) of a virtual wireless network using OPNET Modeler Wireless Suite. Wireless internal and external network simulators such as Remcom's Wireless InSite Real Time (RT) module, WinProp: W-LAN/Fixed WiMAX/Mobile WiMAX, and SMI system, are designed to consider data transfer rate based on wireless propagation signal strength. However, we approached our research in a different perspective without support for characteristic of these wireless network simulators. That is, we will discuss the purpose of a visual analysis for these packets, how to receive each point packets (e.g., wireless user, base station or access point, and http server) through end-to-end virtual network modeling based on integrated wired and wireless network without wireless propagation signal strength. Measuring packet statistics is important in QoS metric analysis among wireless network performance metrics. Clear packet statistics is an especially essential metric in guaranteeing QoS for WiMAX users. We have found some interesting results through modeling and simulation for virtual wireless network using OPNET Modeler Wireless Suite. We are also able to analyze multi-view efficiency through experiment/observation result.

• Journal of Korean Society of Transportation
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• v.23 no.2
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• pp.161-172
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• 2005

This study is to develop Bus Transit Route Analysis and Evaluation Model that can product the quantitative performance measures for Bus Transit Route Network Design. So far, in Korea, there are no so many models that evaluate a variety of other performance measures or service quality that are of concern to both the transit users and operator because of lower-level bus database system and transit route network analysis algorithm's limit. The BTRAEM in this research differ from the previous approach in that the BTRAEM employs a multiple path transit trip assignment model that explicitly considers the transfer and different travel time after boarding. And we develop input-output data structure and quantitative performance measure for the BTRAEM. In the numerical experimental applying BTRAEM to Mandl transit network, We got the meaningful results on performance measure of bus transit route network. In the future, we expect BTRAEM to give a good solution in real transit network.

• Korean Journal of Remote Sensing
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• v.23 no.2
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• pp.103-111
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• 2007

The spectral information based image analysis, visual interpretation and automatic classification have been widely carried out so far for remote sensing data processing. Yet recently, many researchers have tried to extract the spatial information which cannot be expressed directly in the image itself. Using the texture and wavelet scheme, we made a wavelet-based texture fusion image which includes the advantages of each scheme. Moreover, using these schemes, we carried out image classification for the urban spatial analysis and the geological structure analysis around the caldera area. These two case studies showed that image classification accuracy of texture image and wavelet-based texture fusion image is better than that of using only raw image. In case of the urban area using high resolution image, as both texture and wavelet based texture fusion image are added to the original image, the classification accuracy is the highest. Because detailed spatial information is applied to the urban area where detail pixel variation is very significant. In case of the geological structure analysis using middle and low resolution image, the images added by only texture image showed the highest classification accuracy. It is interpreted to be necessary to simplify the information such as elevation variation, thermal distribution, on the occasion of analyzing the relatively larger geological structure like a caldera. Therefore, in the image analysis using spatial information, each spatial information analysis method should be carefully selected by considering the characteristics of the satellite images and the purpose of study.

• The Journal of the Convergence on Culture Technology
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• v.5 no.4
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• pp.387-394
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• 2019

In this study, in order to evaluate the damage and deterioration of the track components of sleeper floating track (STEDEF), the field samples(specimens) were taken from the serviced line over 20 years old, and the track components were visually inspected, and investigated by laboratory tests and finite element analysis. As a result of visual inspection, the damage of the rail pad and fastener was slight, but the rubber boot was worn and torn at the edges of bottom. The resilience pads were clearly examined for thickness reduction and fatigue hardening layer. As a result of spring stiffness test of rail pad and resilience pad, the deterioration of rail pad was insignificant, but the deterioration of resilience pad exceeded design standard value. Therefore resilience pad was directly affected by train passing tonnage. As a result of comparing the deterioration state of the field sample and the numerical analysis result, the stress and displacement concentration position of the finite element model and the damage position of the field sample were coincident.

• Journal of The Korean Society of Integrative Medicine
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• v.9 no.2
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• pp.119-130
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• 2021

Purpose : We aimed to validate a new manual therapy to treat tension type headache(TTH) by applying myofascial release techniques to the scalp and to examine the changes in the quality of life and the headache characteristics after treatment and at the 6-month follow-up. Methods : Thirty patients were recruited in this study and were assigned to two groups through simple random sampling. Fifteen patients were assigned to the manual therapy group (MT) and 15 patients to the scalp myofascial release technique (SMT) group. However, five patients from the MT group and one from the SMT group were excluded. Therefore, 24 patients with TTH (10 males, 14 females) participated in the study. Patients underwent either MT or SMT. The procedures were performed by a physical therapist twice per week for 4 weeks. The quality of life [using the brief pain inventory (BPI) and the headache impact test (HIT)], and the frequency, duration, and intensity of the headache [on a visual analog scale (VAS)] were assessed before and after the treatment, and at the follow-up. Results : After 4 weeks of SMT, the frequency (p<.001), duration (p<.05), and intensity (p<.001) of the headache and the quality of life (HIT; p <.001, BPI; p<.001) significantly improved in the patients with TTH. The improvement in these parameters remained significant even after 6 months of follow-up. Similarly, After 4 weeks of MT, the frequency (p<.05), duration (p<.05), and intensity (p<.01) of the headache, and the quality of life (HIT; p<.05, BPI; p<.001) significantly improved in the patients with TTH. The improvement in these parameters remained significant even after 6 months of follow-up. There was no significant difference in these parameters between the two groups. Conclusion : It has been suggested that MT using the SMT can be used as a non-invasive treatment to treat the frequency, duration, and intensity of the TTH, and to improve the quality of life.

• Land and Housing Review
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• v.12 no.2
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• pp.121-139
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• 2021

Technical documents in the construction field are changing from paper documents to electronic ones. As a result, the industry witnesses a trend of using portable electronic devices in searching or retrieving necessary information such as relevant regulations. Despite the improvement in the accessibility to general technical documents, a limitation is still found in accessing the electronic documents on the regulations. We see the barrier for field engineers to enhance their technical knowledge. One of major barriers is that videos, animations, and virtual reality information to enhance the visual understanding of technical content related to regulations are not linked. It is the interactive electronic technical manual (IETM) that can address such issues. The IETM is an electronic document system that enables real-time information acquisition while operating in the form of conversations with users by linking multimedia functions to document types such as specifications and guidelines. This study establishes a model of the IETM that can be operated in the planning stage of a construction project. The study also verifies its usability with a hypothetical case study. This study aims to improve the usability of the IETM in the construction project by analyzing the application effect of the IETM using the AHP technique.

• Journal of Broadcast Engineering
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• v.23 no.6
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• pp.855-865
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• 2018

Sound event detection is one of the research areas to model human auditory cognitive characteristics by recognizing events in an environment with multiple acoustic events and determining the onset and offset time for each event. DCASE, a research group on acoustic scene classification and sound event detection, is proceeding challenges to encourage participation of researchers and to activate sound event detection research. However, the size of the dataset provided by the DCASE Challenge is relatively small compared to ImageNet, which is a representative dataset for visual object recognition, and there are not many open sources for the acoustic dataset. In this study, the sound events that can occur in indoor and outdoor are collected on a larger scale and annotated for dataset construction. Furthermore, to improve the performance of the sound event detection task, we developed a dual CNN structured sound event detection system by adding a supplementary neural network to a convolutional neural network to determine the presence of sound events. Finally, we conducted a comparative experiment with both baseline systems of the DCASE 2016 and 2017.