• Journal of the Korea institute for structural maintenance and inspection
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• v.15 no.4
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• pp.204-211
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• 2011

A dynamic analysis procedure is developed to provide a better estimation of the dynamic responses of bridge during the passage of high speed railway vehicles. Particularly, a three dimensional numerical model including the structural interaction between high speed vehicles, bridges and railway endures to analyse accurately and evaluate with in-depth parametric studies for dynamic responses of various bridge span lengths running KTX railway locomotive up to increasing maximum speed(450km/h). Three dimensional frame element is used to model the simply supported pre-stressed concrete (PSC) box bridges for four span lengths(40~25m). Track irregularity employed as a stationary random process from the given spectral density functions and irregularities of both sides of the track are assumed to have high correlation. The high-speed railway vehicle (KTX) is used as 38-degree of freedom system. Three displacements (Vertical, lateral, and longitudinal) as well as three rotational components (Pitching, rolling, and yawing) are considered in the 38-degree of freedom model. The dynamic amplification factors are evaluated by the developed procedure under various traveling conditions, such as track irregularity camber, train speed and ballast. The dynamic analysis such as Newmark-${\beta}$ and Runge-Kutta methods which are able to analyse considering the dynamic impact factors are compared and contrasted.

• Journal of KIISE:Information Networking
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• v.32 no.3
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• pp.391-403
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• 2005

Several nv6 mobility support protocols for mobile Internet services are proposed in IETP : Mobile Ipv6, Hierarchical Mobile Ipv6, and Fast Handovers over Mobile Ipv6. Recently, IEEE 802.11 network has also been widely deployed in public areas for mobile Internet services. In the near future, IPv6 mobility support over IEEE 802.11 network is expected to be a key function to actualize the All If-based mobile various services. For appropriate application of these protocols, the IPv6 mobility support protocols should be analyzed according to their characteristics in terms of signaling, handover latency, lost packets, and required buffer sire as well as the impact of lower layer such as IEEE 802.11 network. In this paper, we analyze the performance of the protocols over IEEE 802.11 network. We define a packet-level traffic model, a network system model, and a mobility model. From these models, we construct a framework for the performance analysis. We also make cost functions to formalize each protocol's performance. Lastly, we analyze the effect of varying parameters used to show diverse numerical results, and compare with each other. From the analysis results, it is concluded that each Protocol has contrary or contrastive advantages with other Protocols, so there is no protocol that holds a dominant position.

• Economic and Environmental Geology
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• v.46 no.2
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• pp.105-121
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• 2013

This study introduces integrated approach on detection of a leakage in a sea wall based on remote sensing, electric resistivity survey, electromagnetic survey, and borehole survey for the Seosan A-Region sea wall. The satellite temperature distribution from Landsat ETM+ data identifies water leakage distribution and period by analyzing temperature mixing patterns between sea water and fresh water. Electric resistivity survey provides both horizontal and vertical anomaly distributions over the sea wall showing below average electric resistivity. Electromagnetic survey(electrical conductivity survey) reveals the potential possible leakage areas with minimal background impact by comparing electrical conductivity values between high and low tides. Borehole image processing system confirmed the locations of anomalies identified from the other survey methods and distributions of vertical fracture zones. The integrated approach identified 41.7% of the sea wall being the most probable area vulnerable to water leakage and effectively approximated both horizontal and vertical distribution of water leakage. The integrated analysis of remote sensing, electric resistivity survey, electromagnetic survey and borehole survey is considered to be an optimal method in identifying water leakage distribution, period, and extent of fractures knowledged from the boreholes.

• Journal of Internet Computing and Services
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• v.16 no.1
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• pp.29-37
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• 2015

In this paper, we propose a robust pre-processing module for camera-based Optical Music Score Recognition (OMR) on mobile device. The captured images likely suffer for recognition from many distortions such as illumination, blur, low resolution, etc. Especially, the complex background music sheets recognition are difficult. Through any symbol recognition system, the staff line height and staff line space are used many times and have a big impact on recognition module. A robust and accurate staff line height and staff line space are essential. Some staff line height and staff line space are proposed for binary image. But in case of complex background music sheet image, the binarization results from common binarization algorithm are not satisfactory. It can cause incorrect staff line height and staff line space estimation. We propose a robust staff line height and staff line space estimation by using run-length encoding technique on edge image. Proposed method is composed of two steps, first step, we conducted the staff line height and staff line space estimation based on edge image using by Sobel operator on image blocks. Each column of edge image is encoded by run-length encoding algorithm Second step, we detect the staff line using by Stable Path algorithm and removal the staff line using by adaptive Line Track Height algorithm which is to track the staff lines positions. The result has shown that robust and accurate estimation is possible even in complex background cases.

• The Journal of Korean Medicine
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• v.18 no.1
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• pp.72-81
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• 1997

The causes of stroke are presumed hypertension, atherosclerosis,. cardiac disease, diabetes mellitus and old age and risk factors of stroke are suggested hypertension, hyperlipidemia. obesity, smoking and drinking etc. Especilly, hypertension is one of the most important cause and risk factor of stroke, therfore without therapy hypertension leads to stroke. The frequence of hypertension is significantly higher in hemorrhage patients of intracranial hemorrhage and subarachnoid hemorrhage. Antihypertensive therapy has an impact not only on the primary prevention of stroke but also on stroke recurrence and the declining of stroke motality has been attributed to the widespread availability and use of antihypertensive therapy. The goals of antihypertensive therapy decrease the complications and motalitv of cardiovascular system and prevent the promoting arteriosclerosis. In this study, we observed the blood pressure change of cb-hemorrhagic patients with hypertension who were hospitalized from 1996. 3. 1 to 1997. 2 .26 in Wonkwang Oriental Hospital. These patients had no antihypertensive therapy and were supplied herb med(Jaum sikpoongtang, Chungrijagamtang, Gojinumja) in medication. Our results suggested as follows. 1. Systolic and diastolic average BP at admission is $150.71{\pm}15.61mmHg$ and $95.00{\pm}8.8mmHg$ and this is hypertension state defining WHO 2. During one week in admission, the blood pressure demostrated a marked declination by SBP 8.97mmHg and DBP 6.22mmHg. 3. During two week in admission, the declination of SBP was significant in paired t-test(p<0.05) but, the declination of DBP was non-significant in paired t-test. 4. The blood pressure during third and fourth weeks gradually declined but, non-significant in test. According to the above results, we suggested that the BP declination Was affected by $Jamyang{\cdot}Jaum$ prescriptions in acute stage of cerebral hemorrhage.

• Archives of design research
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• v.11 no.1
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• pp.173-184
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• 1998

This study deals with the visual quality in the future urban landscape and architectural environment, and as such, aims to identify a scientific and objective aesthetic and visual quality from the perspective of empirical aesthetics. The empirical aesthetics provides a framework that can be utilized in understanding human perception, consciousness, and behavior and a way to categorize the visual quality and to explain and predict its effect. The study examines various theories on environmental perception, cognition, and some new approaches to environmental aesthetics, and tries to present aesthetic properties that can be applied to environmental design. First, the aesthetic experience in visual perception can be defined as a combined effect of psychobiological properties and human activity, i.e. an interaction between the formal and symbolic signs in environment and the conceptual framework of man. The effect of visual quality differs and varies a great deal, depending on the sociocultural, personal and collective value system, so it is hard to define it in absolute terms. Second, the impact of visual quality and its aesthetic effect has to do with pleasure, preference, the aptitude for survival, and self regulation. Third, aesthetics is one of the areas that can benefit a great deal from an interdisciplinary approach. and an empirical study such as this can be used as a basis for design, planning, and evaluation.

• Korean Journal of Ecology and Environment
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• v.43 no.2
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• pp.232-241
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• 2010

Epilithic diatom communities and water quality were monitored to evaluate the ecological impact of the inflow of Wonju-stream passing through the urban area in the Seom River Watershed. We selected the 14 sampling stations (5 main stream sites and 9 tributary sites), and collected diatom and water samples between October 2007 and September 2008, on the seasonal basis. The results indicate that most water quality parameters showed the site-specific patterns over the study, except for water temperature and dissolved oxygen. The levels of water quality parameters were highest at the site of Wonju stream, whereas the lowest in the upstream sites, and intermediate or gradually decreased in the downstream sites of the Seom river. One species, Achnanthes convergens, showed the highest biomass and frequency over the sites, while three saprophilous species-Navicula goeppertiana, Navicula subminuscula, Nitzschia palea were appeared only in Wonju Stream and other polluted sites. According to trophic diatom index (TDI) values, which were highly correlated with nutrients and EC, the study sites were classified into three classes: upstream and tributary (Class A and B), Wonju Stream (Class D), and mixed zone and downstream (Class C). A cluster analysis supported the result of TDI classification. Therefore, Wonju-stream located in populated urban area exerted the adverse ecological effects on the epilithic diatom community and water quality of the lower Seom River System, although its severity gradually decreased downstream.

• Journal of the Korean Society for Library and Information Science
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• v.54 no.2
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• pp.5-28
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• 2020

This study was conducted to discuss concrete ways to contribute to the sustainability of the planet by actively applying and using digital and IT resources in libraries. To this end, a survey was conducted for librarians of public libraries, and the results were as follows. First, librarians' awareness of the seriousness of environmental problems and the degree of eco-friendly activities were very high, but their awareness of library green IT and familiarity with eco-related terms were very low. Nevertheless, there was a high degree of agreement on the importance of applying green IT to libraries. Second, the areas evaluated as having the highest contribution to eco-friendliness and greening of the library were found in the equipment and product operation area, followed by the service area and the network and system area. Third, how do you think library green IT will have a social impact? The highest opinion was given that it could increase the awareness of the library's social responsibility as a social infrastructure. In conclusion, it seems that the library's green IT can contribute to improving library perception by making the public perceived as an institution that has a social responsibility as a social infrastructure.

• Imaging Science in Dentistry
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• v.50 no.3
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• pp.227-236
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• 2020

Purpose: Image artifacts caused by patient motion cause problems in cone-beam computed tomography (CBCT) because they lead to distortion of the 3-dimensional reconstruction. This prospective study was performed to quantify patient movement during CBCT acquisition and its influence on image quality. Materials and Methods: In total, 412 patients receiving CBCT imaging were equipped with a wireless head sensor system that detected inertial, gyroscopic, and magnetometric movements with 6 dimensions of freedom. The type and amplitude of movements during CBCT acquisition were evaluated and image quality was rated in 7 different anatomical regions of interest. For continuous variables, significance was calculated using the Student t-test. A linear regression model was applied to identify associations of the type and extent of motion with image quality scores. Kappa statistics were used to assess intra- and inter-rater agreement. Chi-square testing was used to analyze the impact of age and sex on head movement. Results: All CBCT images were acquired in a 10-month period. In 24% of the investigations, movement was recorded (acceleration: >0.10 [m/s²]; angular velocity: >0.018 [°/s]). In all examined regions of interest, head motion during CBCT acquisition resulted in significant impairment of image quality (P<0.001). Movement in the horizontal and vertical axes was most relevant for image quality (R²>0.7). Conclusion: Relevant head motions during CBCT imaging were frequently detected, leading to image quality loss and potentially impairing diagnosis and therapy planning. The presented data illustrate the need for digital correction algorithms and hardware to minimize motion artefacts in CBCT imaging.

• Journal of Korea Society of Industrial Information Systems
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• v.23 no.2
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• pp.75-92
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• 2018

This study investigates the effects of family-friendly corporate policies on employees' job satisfaction, quality of life, organizational commitment, and turnover intention. Data was collected using a self-administered questionnaire from medium sized manufacturing company during the summer of 2017 and received 295 useful responses. The data was analyzed using the multiple and simple regressions. The results showed that the effects of family-friendly corporate policies were significantly positive from the employee's perspective. The employees' awareness of the family-friendly policy was positively correlated with their job satisfaction, quality of life, and organizational commitment, but it was negatively associated with turnover intention. It should be noted that the boss' support at work showed the insignificant effect on the family friendly policy awareness and this result was very different from the previous study. The study concludes that companies as well as employees benefit from family-friendly policies. The study that in order to create a family-friendly corporate culture, the company should not only introduce the policy to employees but also provide the support and atmosphere for the employees to utilize the family-friendly policy easily, and to establish a companywide support policy, organizational practitioners should find the way family-friendly policies to be rooted in the organization.