• Journal of the Korea Academia-Industrial cooperation Society
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• v.18 no.6
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• pp.728-735
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• 2017

With the proliferation of digital devices, the devices have generated considerable additive white Gaussian noise while acquiring digital images. The most well-known denoising methods focused on eliminating the noise, so detailed components that include image information were removed proportionally while eliminating the image noise. The proposed algorithm provides a method that preserves the details and effectively removes the noise. In this proposed method, the goal is to separate meaningful detail information in image noise environment using the edge strength and edge connectivity. Consequently, even as the noise level increases, it shows denoising results better than the other benchmark methods because proposed method extracts the connected detail component information. In addition, the proposed method effectively eliminated the noise for various noise levels; compared to the benchmark algorithms, the proposed algorithm shows a highly structural similarity index(SSIM) value and peak signal-to-noise ratio(PSNR) value, respectively. As shown the result of high SSIMs, it was confirmed that the SSIMs of the denoising results includes a human visual system(HVS).

• Journal of the Institute of Electronics and Information Engineers
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• v.52 no.11
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• pp.3-11
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• 2015

An advanced receiver which can manage inter-cell interference is required to cope with the explosively increasing mobile data traffic. 3rd Generation Partnership Project (3GPP) has discussed network assisted interference cancellation and suppression (NAICS) to improve signal-to-noise-plus-interference ratio (SINR) and receiver performance by suppression or cancellation of interference signal from inter-cells. In this paper, we propose the advanced receiver based on soft decision to reduce the interference from neighbor cell in LTE-Advanced downlink system. The proposed receiver can suppress and cancel the interference by calculating the unbiased estimation value of interference signal using minimum mean square error (MMSE) or interference rejection combing (IRC) receiver. The interference signal is updated using soft information expressed by log-likelihood ratio (LLR). We perform the system level simulation based on 20MHz bandwidth of 3GPP LTE-Advanced downlink system. Simulation results show that the proposed receiver can improve SINR, throughput, and spectral efficiency of conventional system.

• Korean Journal of Remote Sensing
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• v.18 no.4
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• pp.221-231
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• 2002

In this study we applied a DEM generation algorithm developed in-house to satellite images at various resolution and discussed the results. We tested SPOT images at l0m resolution, EOC images at 6.6m and IKONOS images at 1m resolution. These images include the same urban area in Daejeon city. For camera model, we used Gupta & Hartley's(1997) DLT model for all three image sets. We carried out accuracy assessment using USGS DTED for SPOT and EOC and 23 check points for IKONOS. The assessment showed that SPOT DEM had about 38m RMS error, EOC DEM 12m RMS error and IKONOS DEM 6.5m RMS error. In terms of image resolution, SPOT and EOC DEM error corresponds to 2∼4 pixels where as IKONOS DEM error 6∼7pixels. IKONOS DEM contains more errors in pixels. However, in IKONOS DEM, individual buildings, apartments and major roads are identifiable. All three DEMs contained errors due to height discontinuity, occlusion and shadow. These experiments show that our algorithm can generate urban DEM from 1m resolution and that, however, we need to improve the algorithm to minimize effects of occlusion and building shadows on DEMs.

• Journal of the Korea Institute of Construction Safety
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• v.1 no.1
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• pp.22-30
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• 2018

Construction accidents in Korea are continuously increasing. Safety signs with high visibility color can diminish such accidents in dangerous places. In order for safety color to be more effective as a global communication means in construction sites, it needs to be checked out whether safety color standard reflect the characteristics of construction industry such as worker or work environment. This paper compared safety color standards among Korea, the US, the UK, and Australia. First, blue color was included in all, which should be corrected considering aged workers increasing in construction industry. Because with age, the ability to distinguish between blue, purple, and gray colors decreases. Second, Korea, which has only single code designated to safety colors, should find alternatives like tolerance to be applicable to a variety of light environments on construction sites, as the contrast which affect the visibility may decrease in dark conditions.

• Journal of The Korean Association For Science Education
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• v.39 no.4
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• pp.535-544
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• 2019

In order to find out whether the traditional mass media in our society are sufficiently functioning as a vehicle of providing scientific information to the public outside the school education, public perception of science articles in mass media and scientific terms used in high frequency in science articles have been examined. To investigate the public perception on science articles, a questionnaire was constructed about the usefulness, importance, access frequency, and understanding of science articles. The questionnaires were conducted in areas with high flow populations such as train stations or subway stations. A total of 425 responses were used for analysis. In order to extract high frequency scientific terms used in science articles, two television companies and two newspapers were designated as target media, and their texts on science articles reported over the last 17 years were collected to investigate the frequency of scientific terms used. Based on the frequency, we conducted the self-report comprehension test for the top 100 scientific terms. The results of this study show that the public in our society has relatively high perception of the importance and usefulness of science articles, however, reading and understanding the articles seems to be somewhat difficult. In addition, the scientific terminology used in science articles has a high degree of comprehension for those of higher education, natural sciences majors, and men. In addition, scientific terms with high understanding degree were characterized according to gender, age, educational background, and field of major.

• Korean Journal of Remote Sensing
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• v.35 no.5_2
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• pp.819-829
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• 2019

In the disaster of collapse, an immediate response is needed to prevent the damage from worsening, and damage area calculation, response and recovery plan should be established. This requires accurate detection of the damage affected area. This study performed the detection of the damaged area by using UAV which can respond quickly and in real-time to detect the collapse accident. The study area was selected as B-05 housing redevelopment area in Jung-gu, Ulsan, where the demolition of houses and apartments in progress as the redevelopment project began. This area resembles a collapsed state of the building, which clear changes before and after the demolition. UAV images were acquired on May 17 and July 9, 2019, respectively. The changing area was considered as the damaged area before and after the collapse of the building, and the changing area was detected using CVA (Change Vector Analysis) the Representative Change Detection Technique, and SLIC (Simple Linear Iterative Clustering) based superpixel algorithm. In order to accurately perform the detection of the damaged area, the uninterested area (vegetation) was firstly removed using ExG (Excess Green), Among the objects that were detected by change, objects that had been falsely detected by area were finally removed by calculating the minimum area. As a result, the accuracy of the detection of damaged areas was 95.39%. In the future, it is expected to be used for various data such as response and recovery measures for collapse accidents and damage calculation.

• Geophysics and Geophysical Exploration
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• v.6 no.4
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• pp.199-206
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• 2003

Characteristics of the static shift are discussed by comparing the three-dimensional MT inversion with/without static shift parameterization. The galvanic distortion by small-scale shallow feature often leads severe distortion in inverted resistivity structures. The new inversion algorithm is applied to four numerical data sets contaminated by different amount of static shift. In real field data interpretations, we generally do not have any a-priori information about how much the data contains the static shift. In this study, we developed an algorithm for finding both Lagrangian multiplier for smoothness and the trade-off parameter for static shift, simultaneously in 3-D MT inversion. Applications of this inversion routine for the numerical data sets showed quite reasonable estimation of static shift parameters without any a-priori information. The inversion scheme is successfully applied to all the four data sets, even when the static shift does not obey the Gaussian distribution. Allowing the static shift parameters have non-zero degree of freedom to the inversion, we could get more accurate block resistivities as well as static shifts in the data. When inversion does not consider the static shift as inversion parameters (conventional MT inversion), the block resistivities on the surface are modified considerably to match possible static shift. The inhomogeneous blocks on the surface can generate the static shift at low frequencies. By those mechanisms, the conventional 3-D MT inversion can reconstruct the resistivity structures to some extent in the deeper parts even when moderate static shifts are in the data. As frequency increased, however, the galvanic distortion is not frequency independent any more, and thus the conventional inversion failed to fit the apparent resistivity and phase, especially when strong static shift is added. Even in such case, however, reasonable estimation of block resistivity as well as static shift parameters were obtained by 3-D MT inversion with static shift parameterization.

• Journal of Convergence for Information Technology
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• v.8 no.3
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• pp.25-32
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• 2018

This descriptive research is to find communication ability, general and social self-efficacy, and academic achievement in peer collaboration subject of nursing freshmen. The data were analyzed by SPSS/WIN 19.0. The communication ability was higher in the extroverts and high discussion preference ones(p=.01), females' social self-efficacy were higher than males'(p=.03), the general and social self-efficacy of the 'introverted' and 'middle' groups were higher than the extroverts'(p=.01). The social self-efficacy on the 'middle high', 'middle' and 'middle low' of self-evaluated school grades groups were higher than 'high' one's, even the academic achievement of 'high' group was the most(p=.01). There were negative correlations between communication ability and self-efficacy, and between social self-efficacy and academic achievement. And social self-efficacy affected on the academic achievement in peer collaboration subject($R^2=0.058$, p<.05). These results can be used as a basis for developing guidelines of nursing freshmen who have to complete a lot of theoretical and practical courses in university.

• Journal of Convergence for Information Technology
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• v.9 no.12
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• pp.302-312
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• 2019

The purpose of this study was to analyzed the effects of educational recognition sub-factors (necessity, utility, value, cost, adequacy) on the field usability and satisfaction and the correlation between each factor for 220 applicants who have taken the national technical certificate of cosmetologist (make-up). In the practical courses of makeup certificate, the most-used course was selected as beauty makeup. It found for improvement need cause there was a high necessity and there was a low recognition of the cost, the number of annual written and practical test in the recognition of certification education. In field usability 'Beauty make-up utilization' showed high recognition, and it showed high satisfaction for acquisition of certificate satisfaction, 'The salary' showed low recognition. The necessity, cost, adequacy among educational recognition sub-factor of the national technical certificate had a significant positive effect on the field usability and satisfaction, and showed the most effect as adequacy on the field usability and the cost on the satisfaction. Therefore, efforts are needed to reduce acquisition costs of certificate and improve highly available theories and technique for segmentation and specialization of make-up certificate.

• Journal of the Korean Society of Hazard Mitigation
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• v.11 no.2
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• pp.163-170
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• 2011

Natural stream disasters due to a localized torrential and flash flood has occurring in a small stream especially un-implemented small stream. The survey results during ten years from 2001 to 2010 show that the small stream implementation projects (SSIPs) expenses is increasing with the damages is generally decreasing with variableness in which SSIPs is contributing to disaster prevention in a small stream. This study develop guideline for the selection of SSIPs to support high risk stream at first and save the small streams located on the mountainous area, prevention area and agricultural area which streams have no implementation effects. Developed sub items in guideline are evaluated by stream data collected from 212 small streams where it is proved that sub distance of each item are well arranged by normal distribution. This SSIPs is useful for selecting high risk small stream at first to maximize disaster risk reduction with minimum SSIPs expenses. Also, this SSIPs is used for leading to save small stream on the upstream to minimize flood damages on the down stream with selection a SSIP purchasing agricultural land for preparing flood plane.