• Title/Summary/Keyword: digital inspection

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A Study on Cost Reduction Effect of Drone Implementation in Traffic Survey (교통조사부문 드론 활용시 비용절감효과 분석 연구)

  • Kim, Dongjun;Ahn, Hyosub;Kim, Jin-tae
    • International Journal of Highway Engineering
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    • v.20 no.4
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    • pp.73-84
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    • 2018
  • PURPOSES : Most of the traffic surveys are carried out by an inspection method by the manpower. In some cases, the video equipment is used only in some regions when the traffic volume is surveyed. In this case, there is environmental restriction that the road equipment to fix the video equipment should exist. Also, in areas where information such as digital maps and satellite photographs is old or not provided, they are forced to rely on manpower research, but it is difficult to put huge amounts of time and money into the research in places where labor supply and demand is difficult. This difficulty is particularly pronounced in overseas business. METHODS : The purpose of this study is to improve the efficiency of business by using the drones in the traffic investigation through analysis of the cost reduction effect between the existing method and the proposed method in the overseas business traffic survey. The scope of the research is limited to the scope of research, and based on the case of overseas projects, the method of using drone for each research sector is suggested. RESULTS : In the traffic condition survey section, we propose the use of drone for traffic survey and queue length survey, and it is confirmed that there is a cost saving effect of 16% ~ 27% compared with the existing method. In the road condition survey, we propose the use of drones for road surface linear survey, geometry survey, and obstacle survey, and it was confirmed that the cost reduction effect is 39% ~ 93% compared to the existing method. CONCLUSIONS : In addition to overseas business, it is expected that it will have a positive effect on research time and cost reduction by using drone in traffic survey in domestic area where labor supply is not easy or basic data is insufficient.

Evaluation of HSPF Model Applicability for Runoff Estimation of 3 Sub-watershed in Namgang Dam Watershed (남강댐 상류 3개 소유역의 유출량 추정을 위한 HSPF 모형의 적용성 평가)

  • Kim, So Rae;Kim, Sang Min
    • Journal of Korean Society on Water Environment
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    • v.34 no.3
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    • pp.328-338
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    • 2018
  • The objective of this study was to evaluate the applicability of a HSPF (Hydrological Simulation Program-Fortran) model for runoff estimation in the Namgang dam watershed. Spatial data, such as watershed, stream, land use, and a digital elevation map, were used as input for the HSPF model, which was calibrated and validated using observed runoff data from 2004 to 2015 for three stations (Sancheong, Shinan, Changchon) in the study watershed. Parameters for runoff calibration were selected based on the user's manual and references, and parameter calibration was done by trial and error. The $R^2$ (determination coefficient), RMSE (root-mean-square error), NSE (Nash-Sutcliffe efficiency coefficient), and RMAE (relative mean absolute error) were used to evaluate the model's performance. Calibration and validation results showed that annual mean runoff was within a ${\pm}5%$ error in Sancheong and Shinan, whereas there was a14% error in Changchon. The model performance criteria for calibration and validation showed that $R^2$ ranged from 0.80 to 0.92, RMSE was 2.33 to 2.39 mm/day, NSE was 0.71 to 0.85, and RMAE was 0.37 to 0.57 mm/day for daily runoff. Visual inspection showed that the simulated daily flow, monthly flow, and flow exceedance graph agreed well with observations for the Sancheong and Shinan stations, whereas the simulated flow was higher than observed at the Changchon station.

Automatic Extraction of 3-Dimensional Road Information Using Road Pavement Markings (도로 노면표지를 이용한 3차원 도로정보 자동추출)

  • Kim, Jin-Gon;Han, Dong-Yeub;Yu, Ki-Yun;Kim, Yong-Il
    • Journal of Korean Society for Geospatial Information Science
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    • v.12 no.4 s.31
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    • pp.61-68
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    • 2004
  • In this paper, we suggest an automatic technique to obtain 3-D road information in complex urban areas using road pavement markings. This method is composed of following three main steps. The first step is extracting the pavement markings from aerial images, the second one is matching the same pavement markings in two aerial images, and the last one is obtaining the 3-D coordinates of those using EOP(exterior orientation parameters) of aerial images. Here, we focus on the first and second step because the last step can be performed by using the well hewn collinearity condition equation. We used geometric properties and spatial relationships of the pavement markings to extract the lane line markings on the images and extracted arrow lane markings additionally using template matching. And then, we obtained 3-D coordinates of the road using relational matching for the pavement markings. In order to evaluate the accuracy of extraction, we did a visual inspection and compared the result of this technique with those measured by digital photogrammetric system.

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KVN Observation on Radio-selected AGNs hosted by Elliptical Galaxies

  • Park, Song-Youn;Yi, Suk-Young K.;Sohn, Bong-Won
    • The Bulletin of The Korean Astronomical Society
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    • v.36 no.2
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    • pp.61.1-61.1
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    • 2011
  • We have performed simultaneous observations at 22GHz and 43GHz on AGNs hosted by elliptical galaxies using KVN radio telescope. We have constructed the sample, based on two major surveys in radio and optical band, i.e. Faint Images of the Radio Sky at Twenty-Centimeters (FIRST) and Sloan Digital Sky Survey (SDSS) DR7, respectively. We restricted the redshift range 0.01 < z < 0.06 and the absolute magnitude Mr < -19.4 in order to satisfy volume limited sample. We also checked clear detection of four distinctive emission lines ([NII], [OIII], $H{\alpha}$, $H{\beta}$) so as to utilize on BPT diagram, distinguishing AGNs from star-forming galaxies. Elliptical galaxies have been selected by visual inspection making use of SDSS optical images. Then, we cross-matched the elliptical galaxies with FIRST detections. About 35% of the galaxies have been detected throughout KVN observations. We derive spectral index, applying the flux of different radio frequencies from FIRST (1.4GHz) and KVN (22GHz) and classify into steep, flat or inverted spectrum. We have found that most of the detected galaxies have flat spectrum while the rest of them have steep spectrum. This implies that a number of detected galaxies might have compact structure associated with the central region of the galaxies. The relation between black hole mass and radio luminosity has shown relatively tighter correlation in high frequency than in low frequency, which confirms that high frequency in radio band is appropriate to study the center of the galaxies.

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Enhanced Nitrogen in Morphologically Disturbed Blue Compact Galaxies at 0.20 < z < 0.35: Probing Galaxy Merging Features

  • Chung, Jiwon;Rey, Soo-Chang;Sung, Eon-Chang;Yeom, Bum-Suk;Humphrey, Andrew;Yi, Wonhyeong;Kyeong, Jaemann
    • The Bulletin of The Korean Astronomical Society
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    • v.38 no.1
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    • pp.39-39
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    • 2013
  • We present a study of correlations between the elemental abundances and galaxy morphologies of 91 blue compact galaxies (BCGs) at z=0.20-0.35 with Sloan Digital Sky Survey (SDSS) DR7 data. We classify the morphologies of the galaxies as either 'disturbed' or 'undisturbed', by visual inspection of the SDSS images, and using the Gini coefficient and M20. We derive oxygen and nitrogen abundances using the Te method. We find that a substantial fraction of BCGs with disturbed morphologies, indicative of merger remnants, show relatively high N/O and low O/H abundance ratios. The majority of the disturbed BCGs exhibit higher N/O values at a given O/H value compared to the morphologically undisturbed galaxies, implying more efficient nitrogen enrichment in disturbed BCGs. We detect Wolf-Rayet (WR) features in only a handful of the disturbed BCGs, which appears to contradict the idea that WR stars are responsible for high nitrogen abundance. Combining these results with Galaxy Evolution Explorer (GALEX) GR6 ultraviolet (UV) data, we find that the majority of the disturbed BCGs show systematically lower values of the $H{\alpha}$ to near-UV star formation rate ratio. The equivalent width of the $H{\beta}$ emission line is also systematically lower in the disturbed BCGs. Based on these results, we infer that disturbed BCGs have undergone star formation over relatively longer time scales, resulting in a more continuous enrichment of nitrogen. We suggest that this correlation between morphology and chemical abundances in BCGs is due to a difference in their recent star formation histories.

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Local Environmental Effects on AGN Activities

  • Kim, Jaemin;Yi, Sukyoung K.
    • The Bulletin of The Korean Astronomical Society
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    • v.38 no.1
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    • pp.43.2-43.2
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    • 2013
  • The local environmental effects on the triggering of active galactic nucleus(AGN) activity has been studied with many authors, but there still be controversy. We perform statistical analysis for nearby(0.01 < z < 0.05) volume limited(Mr < -19) samples with visual inspection based on Sloan Digital Sky Survey Data Release7. We inspect ~60,000 galaxy images visually to find peculiar objects which show not only ongoing merging features and tidal features, but also post merging features like ring or shell structures. We found that these peculiar features were shown at least 2 times more frequently among AGN host galaxies than non AGN galaxies, and this trend was still visible when galaxy properties such as color or stellar mass are fixed. Furthermore, L[OIII] and L(Ha) of peculiar galaxies are found to be more increased than those of normal galaxies. In order to ensure this results, we also checked it for a smaller subsample with ~2mag deeper monochromatic images provided from SDSS Stripe82 database, and found consistent results. At last, we perform the same work for pair(r_p<80kpc/h, delta_v<200km/s) systems. Because of some pair systems which do not interact gravitationally in actuality but fulfill the criteria for identification of pair system, the trends are found to be slightly weaker. We also found that line luminosities are increased consistently as projected distance between central and companion galaxy decreased, and as companion color gets bluer. Overall, the results of this study tell us that the local environment of galaxies affect the frequency as well as the strength of AGN activity. Local environmental effects, however, may not be the dominant triggering mechanism for AGN activity since the majority of peculiar galaxies are non AGN galaxies.

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ON THE NATURE OF SODIUM EXCESS OBJECTS

  • Jeong, Hyunjin;Yi, Sukyoung K.;Kyeong, Jaemann;Sarzi, Marc;Sung, Eon-Chang;Oh, Kyuseok
    • The Bulletin of The Korean Astronomical Society
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    • v.39 no.1
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    • pp.47.2-47.2
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    • 2014
  • Several studies have reported the presence of sodium excess objects having neutral atomic absorption lines at $5895{\AA}$ (NaD) and $8190{\AA}$ that are deeper than expected based on stellar population models that match the stellar continuum. The origin of these lines is therefore hotly debated. van Dokkum & Conroy proposed that low-mass stars (0.3M) are more prevalent in massive early-type galaxies, which may lead to a strong NaI 8190 line strength. It is necessary to test this prediction, however, against other prominent optical line indices such as NaD, Mgb, and Fe5270, which can be measured with a significantly higher signal-to-noise ratio than NaI 8190. We identified a new sample of roughly one thousand NaD excess objects (NEOs; ~8% of galaxies in the sample) based on NaD line strength in the redshift range 0.00$H{\beta}$ line strengths and significant emission lines, which are indicative of the presence of young stellar populations. This result implies that the presence of the interstellar medium and/or dust contributes to the increase in NaD line strengths observed for these galaxies.

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Texture Analysis Algorithm and its Application to Leather Automatic Classification Inspection System (텍스처 분석 알고리즘과 피혁 자동 선별 시스템에의 응용)

  • 김명재;이명수;권장우;김광섭;길경석
    • Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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    • 2001.10a
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    • pp.363-366
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    • 2001
  • The present process of grading leather quality by the rare eyes is not reliable. Because inconsistency of grading due to eyes strain for long time can cause incorrect result of grading. Therefore it is necessary to automate the process of grading quality of leather based on objective standard for it. In this paper, leather automatic classification system consists of the process obtaining the information of leather and the process grading the quality of leather from the information. Leather is graded by its information such as texture density, types and distribution of defects. This paper proposes the algorithm which sorts out leather information like texture density and defects from the gray-level images obtained by digital camera. The density information is sorted out by the distribution value of Fourier spectrum which comes out after original image is converted to the image in frequency domain. And the defect information is obtained by the statistics of pixels which is relevant to Window using searching Window after sort out boundary lines from preprocessed images. The information for entire leather is used as standard of grading leather quality, and the proposed algorithm is practically applied to machine vision system.

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Analysis of Commercial Older Drivers Riskiness using Transport Workers Management System (운수종사자시스템을 활용한 사업용 고령운전자의 위험성 분석)

  • Hur, Jung-Chul;Lee, Choul-Ki;Chon, Chun-Taek
    • The Journal of The Korea Institute of Intelligent Transport Systems
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    • v.16 no.6
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    • pp.16-28
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    • 2017
  • In this study, we analyzed the result of new inspection, accidents, penalties, and operation records of the elderly driver's driving aptitude test in the city bus using the Transport Workers Management System and the Digital Tachograph Analysis System(eTAS). As a result of the analysis, the results of the driver aptitude test were similar when compared with the traffic company which has many bus drivers and the well - And it was confirmed that the average number of serious injuries and slight injuries in case of accidents was small. Comparing the number of dangerous driving behaviors per 100 km of driving, the elderly driver of the excellent company showed that the number of dangerous driving behaviors is considerably smaller than other elderly and non - elderly drivers, and that the result of correcting the wrong driving habits.

The Design of Military Security Audit based on the M-ISMS Model (M-ISMS 모델 기반의 군(軍) 보안감사 설계에 관한 연구)

  • Kim, Dae Gyu;Cho, Hee Joon;Kim, Chang Soo
    • Journal of the Korea Institute of Information and Communication Engineering
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    • v.18 no.3
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    • pp.761-769
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    • 2014
  • We propose an improved M-ISMS(Military-ISMS) model which is based on common ISMS model for regarding military's unique characteristics. Our model focuses on 'Internal Security Audit' and 'Management of external activity' as military circumstances. So, we added the six control new items as internal security audits. Because the confidentiality is more important than availability in military service as compared with private sectors. In addition, we propose some control suggestions for establishing security management standards and keeping level maintenance when it will becomes to lose a value as confidential. The M-ISMS model in this paper has effectiveness which prevents security incidents in advance rapidly throughout a variety of common ISMS's advantages and security incidents of private sectors in consideration of military characteristics.