• Journal of the Society of Disaster Information
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• v.19 no.4
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• pp.976-983
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• 2023

Purpose: The dynamic behavior of a bridge structure under seismic loading depends on many uncertainties, such as the nature of the seismic waves and the material and geometric properties. However, not all uncertainties have a significant impact on the dynamic behavior of a bridge structure. Since probabilistic seismic performance evaluation considering even low-impact uncertainties is computationally expensive, the uncertainties should be identified by considering their impact on the dynamic behavior of the bridge. Therefore, in this study, a global sensitivity analysis was performed to identify the main parameters affecting the dynamic behavior of bridges with I-curved girders. Method: Considering the uncertainty of the earthquake and the material and geometric uncertainty of the curved bridge, a finite element analysis was performed, and a surrogate model was developed based on the analysis results. The surrogate model was evaluated using performance metrics such as coefficient of determination, and finally, a global sensitivity analysis based on the surrogate model was performed. Result: The uncertainty factors that have the greatest influence on the stress response of the I-curved girder under seismic loading are the peak ground acceleration (PGA), the height of the bridge (h), and the yield stress of the steel (fy). The main effect sensitivity indices of PGA, h, and fy were found to be 0.7096, 0.0839, and 0.0352, respectively, and the total sensitivity indices were found to be 0.9459, 0.1297, and 0.0678, respectively. Conclusion: The stress response of the I-shaped curved girder is dominated by the uncertainty of the input motions and is strongly influenced by the interaction effect between each uncertainty factor. Therefore, additional sensitivity analysis of the uncertainty of the input motions, such as the number of input motions and the intensity measure(IM), and a global sensitivity analysis considering the structural uncertainty, such as the number and curvature of the curved girders, are required.

• The Journal of Korean Society for Radiation Therapy
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• v.22 no.2
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• pp.113-122
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• 2010

Purpose: To evaluate the accuracy of a target position at static and dynamic state by using Dynamic phantom for the difference between tumor's actual movement during respiratory gated radiation therapy and skin movement measured by RPM (Real-time Position Management). Materials and Methods: It self-produced Dynamic phantom that moves two-dimensionally to measure a tumor moved by breath. After putting marker block on dynamic phantom, it analyzed the amplitude and status change depending on respiratory time setup in advance by using RPM. It places marker block on dynamic phantom based on this result, inserts Gafchromic EBT film into the target, and investigates 5 Gy respectively at static and dynamic state. And it scanned investigated Gafchromic EBT film and analyzed dose distribution by using automatic calculation. Results: As a result of an analysis of Gafchromic EBT film's radiation amount at static and dynamic state, it could be known that dose distribution involving 90% is distributed within margin of error of 3 mm. Conclusion: As a result of an analysis of dose distribution's change depending on patient's respiratory cycle during respiratory gated radiation therapy, it is expected that the treatment would be possible within recommended margin of error at ICRP 60.

• Archives of design research
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• v.17 no.4
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• pp.223-232
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• 2004

The pedestrian space on the roads shows virtually different images, depending on the local uniqueness that exists in the roadsides, to the one walking. This sort of characteristics of the region originated from the physical special structures of the roadside building the form of the place. Thus, because of the structural difference of the roadside, Pedestrian sense the difference of regions through other images. Research focused on issues of the local roadside sidewalk spaces as what roadside structure is the type that brings out the unique images of the region, and what facets are pursued additionally here, is needed. A roadside of a prosperous region filled with many Pedestrians is selected as the range for the experiment in order to analyze the structure and image of the pedestrian space. Among the roads of the selected region, the structure of the pedestrian space on the roads with more than four lanes was evaluated. As result of the analysis, the images of 10 pedestrian space could be classified into two groups by the difference in proportions of the Df/H(the width of the sidewalk and the height of the roadside building) and the D/H(the width of the road and the height of the roadside building). In order to observe the images of the pedestrian space classified into two groups, the adjectives used to describe the image of scenery were researched, enabling one to induce the images of the two groups form them. One of the images is the image of prosperities, and the other is the image of pleasantness. In addition, as result to the evaluation focused on the characteristic of the roadside buildings in the selected area, it could be divided into two groups, i.e., the commercial region and the business region. The image of prosperities was sensed on the sidewalks of the commercial region, while the image of pleasantness was seen on that of the business region. This study enabled the acknowledgment that in a pedestrian space on a road structure with more than four lanes, the Pedestrian sense different images, depending on the proportional difference in the width of the sidewalk & the height of the roadside building, and the width of the road & the height of the roadside building. This result is expected to be a good reference when a road structure reflecting the uniqueness of its region is to be designed, and especially when the structure of a pedestrian space is to be created.

• Journal of Wetlands Research
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• v.18 no.4
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• pp.456-464
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• 2016

Korea established an inventory of 1,916 sites of inland wetlands during a nationwide investigation from 2000 to 2010. If inland wetlands is included in or near various protected areas designated by the government, it can be selected as a wetland to be managed with priority. This study evaluated the aspect of management of inland wetlands by analyzing the correlation between locations of national protected areas and inland wetlands. As a result, it was shown that a considerable percentage of current inland wetland was located in areas that were designated and managed as protected areas by the government, as they had a high value of natural environment protection (527 sites, 31.61 %). When the range was widened to a radius of 1 km for protected areas, 959 sites were included and 57.53 % of sites were located in or nearby the protected areas. Among them, 46.79 % of sites were distributed up to or within a 1 km radius of waterside areas and rivers; it accounted for 81.33 % of wetlands located in protected areas. Therefore, it was found that locations of current inland wetlands were mostly in contact with rivers. The results of overlay analysis were classified into high, medium and low; the correlation of location with inland wetlands was analyzed through the analysis of separation distance of various protected areas. The number of wetlands located in areas of a 'high' value of protection was 998 (59.87 %); 289 sites (17.34 %) were distributed in areas of a 'low' value of protection. This implies that these wetlands are located in artificial areas and are more exposed to environmental pressures. Thus, these wetlands could be determined as inland wetlands, which we considered for the establishment of measures to prevent damage.

• Journal of the Korea Convergence Society
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• v.11 no.4
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• pp.125-131
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• 2020

As technology advances, the importance of software education is increasing. Accordingly, interest in information subjects is increasing, but intending elementary learners to show algorithms only for specialized IT skills that could spoil the interest. In this paper for the elementary school students, through the four stages, 2015 revision curriculum analysis, creating of training program development operating plans, applying programs for the targeting students and analysis of results and evaluation, using Rich Picture technique which is various tools such as pictures and speech bubble symbols for the learners can express the intelligent CCTV algorithm freely and easily so they can understand fully about the algorithm of intelligent CCTV that uses artificial intelligence to extract faces from subjects. Suggest on this paper, the proposal of educational program can help the learner to grasp the principle of the algorithm by using the flowchart. As the result, Through the modification and development of the proposed program, we will conduct research on IT creative education that can be applied in various areas.

• Journal of Korean Society of Steel Construction
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• v.15 no.1
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• pp.1-8
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• 2003

In locations where the cost of concrete is relatively high or in situations where the weight of concrete members has to be kept to a minimum, it may be more economical to use hollow reinforced concrete vertic al members. Hollow reinforced concrete colun-ms with a low axial load, a moderate longitudinal steel percentage and a reasonably thick wall were found to perform in a ductile manner at the flexural strength, similar to solid columns. Hollow reinforced concrete columns with a high axial load, a high longitudinal steel percentage, and a thin wall were found, however, to behave in a brittle manner at the flexural strength, since the neutral axis is forced to occur away from the inside face of the tube towards the section centroid and, as a result, crushing of concrete occurs near the unconfined inside face of the section. If, however, a steel tube is placed near the inside face of a circular hollow column, the column can be expected not to fail in a brittle manner through the disintegration of the concrete in the compression zone. A design recommendation and example through the moment-curvature analysis program for curvature ductility are herein presented. A theoretical moment-curvature analysis for reinforced concrete columns, indicating the available flexural strength and ductility, can be conducted, providing that the stress-strain relation for the concrete and steel are known. In this paper, a unified stress-stain model for confined concrete by Mander is developed foi members with circular sections.

• The Journal of the Korea Contents Association
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• v.9 no.8
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• pp.285-293
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• 2009

The purpose of this study is to closely examine the effect of exercise behavior change of casino securities on their Self-efficacy. This observation takes place in casino enterprises in the whole country. Within these areas, we set the selected employees as the targeted sampling unit, we extracted the specimen, using the stratified cluster random sampling with the quota sampling, putting a weigh on the specimen of focused areas. Among 420 persons sampling unit, we have excluded 47 copied which seem to be insincere, and actually used 373 copies in this study. Evaluation forms are used as a study method; each form consists of continuance 5 points Likert scales and nominal/proportional scaling and used after excluding a test through the analysis of validity and reliability. After encoding and inputting the framing completed data along with each purpose, it was computerized by computer process, making use of SPSS 15.0 version. Through the data analysis according to these methods and procedures, the result on this study is described below. First, the exercise behavior change process the self-efficacy according to socio-demographic characteristics make a difference. Second, the self-efficacy according to socio-demographic characteristics make a difference. Third, the exercise behavior change process influence on the self-efficacy.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.17 no.7
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• pp.400-409
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• 2016

The geospatial information industry has the advantage of being able to converge with other industries to create new value. Therefore, efforts are underway to promote the growth of this dwindling national industry by endorsing policies and initiatives to promote its convergence with other industries. In this study, feedback was collected from experts in various fields through three rounds of polls using the Delphi method. The poll results were used to investigate the causes of hindrance to the growth of the geospatial information industry and to build a comprehensive solution to this problem. As a result, 27 strategies were constructed based on the users' requirements related to policy, data and service, including the demands for establishing public polling methods, enhancing data quality and advertisement. Since the coefficient of variance fell between 0.11 and 0.20 in the importance evaluation, an amicable consensus was reached between the experts. Considering that the convergence of industries is achieved through the integration of various types of technology and information, it is important to consider the requirements of users in different industries. In this respect, the results of this study will serve as a useful base for constructing mid-to-long term road maps to promote the development of the geospatial information industry.

• Tunnel and Underground Space
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• v.25 no.2
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• pp.186-198
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• 2015

This paper aims for the ultimate goal to optimize the work place environment through assuring the optimal required ventilation rate based on the analysis of the airflow. The working environment is deteriorated due to a rise in temperature of a coal mine caused by increase of its depth and carriage tunnels. To improve the environment, the ventilation evaluation on J coal mine is carried out and the effect of a length of the tunnel on the temperature to enhance the ventilation efficiency in the subsurface is numerically analyzed. The analysis shows that J coal mine needs $17,831m^3/min$ for in-flow ventilation rate but the total input air flowrate is $16,474m^3/min$, $1,357m^3/min$ of in-flow ventilation rate shortage. The temperatures were predicted on the two developed models of J mine, and VnetPC that is a numerical program for the flowrate prediction. The result of the simulation notices the temperature in the case of developing all 4 areas of -425ML as a first model is predicted 29.30 at the main gangway 9X of C section and in the case of developing 3 areas of -425ML excepting A area as a second model, it is predicted 27.45 Celsius degrees.

• Journal of the Korean Society of Marine Environment & Safety
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• v.13 no.3
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• pp.207-212
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• 2007

This paper aims to measure and evaluate the technical efficiency with two inputs and four outputs with the use of fuzzy DEA in Korean RCC/RSC. Especially, this paper included not only the marine accident data which occurred for the analysis in particular but also the possibility data of a potential marine accident by an Environmental Stress value and analyzed the technical efficiency. And in this paper, asymmetrical triangular fuzzy number is presented about inputs/ outputs data and a procedure is suggested for it's solution. The basic idea is to transform the fuzzy CCR model into a crisp linear programming problem by applying an alternative ${\alpha}$-cut approach. Also this paper propose a ranking method for fuzzy RCC/RSC using presented fuzzy DEA approach. The result, when ${\alpha}$-cut is 0.5, efficiency priority is found in the order of YS, BS, MP, TY, JJ, PH, US, IC, SC, DH, GS, TA, WD RCC/RSC. Finally, Inefficiency TA, WD RCC/RSC have to benchmarking with reference sets.