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Airborne video as a remote sensor for environmental monitoring of linear infrastructure: a case study and review

  • Um Jung-Sup
    • Spatial Information Research
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    • v.12 no.4 s.31
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    • pp.351-370
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    • 2004
  • At present, environmental monitoring of linear infrastructure is based mainly on field sampling. The 'integrated mapping' approach has received only limited attention from field scientists. The increased environmental regulation of corridor targets has required remote sensing research to develop a sensor or technique for targets ranging from 15 m to 100 m in swath width. In an attempt to identify the optimal remote sensing system for linear targets, an overview is provided of the application requirements and the technology currently available. The relative limitation of traditional remote sensing systems in such a linear application is briefly discussed. It is noted that airborne video could provide, in a cost-effective manner, information required for a very narrow and long strip target utilising the narrow view angle and dynamic stereo coverage. The value of this paper is warranted in proposing a new concept of video infrastructure monitoring as a future research direction in the recognition of sensor characteristics and limitations.

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Case History for Safe Diagnosis of Embankment Dike using Composite Analysis of Various Geophysical surveys (물리탐사 결과 복합해석을 통한 방조제 제체 정밀안전진단 사례)

  • Song, Sung-Ho;Seong, Baek-Uk;Kim, Young-Gyu;Kang, Mi-Kyung;Lee, Gyu-Sang;Kim, Yang-Bin
    • 한국지구물리탐사학회:학술대회논문집
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    • 2007.06a
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    • pp.107-112
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    • 2007
  • To establish the reinforce region and technique through the embankment dike after identifying the region of seawater inflow, we carried out small-loop electromagnetic (EM) survey, electrical resistivity survey and refraction seismic method. We also analyzed the distribution of electrical conductivity in reservoir with depth every two month and monitored water level variations with tidal variation in four observation wells located at seaside and reservoir side in order to analyze the relationship with survey results. From both the cross-correlation between tidal and water level variation at four wells and the distribution of electrical conductivity in reservoir with depth, the major portion of seawater inflow are identified through the embankment dike. From electromagnetic and electrical resistivity survey results, it was found that the seawater inflow were happened through several small regions at seaside and became wider near reservoir side. The 2-D inversion sections of refraction seismic method showed that the pebble-bearing sand layer is spread over the whole region with two to four width. From the this study, small-loop EM, electrical resistivity and refraction seismic surveys accompany with the distribution of electrical conductivity in reservoir with depth and the monitoring results for water level variations are revealed to be effective to identify seawater inflow pathway through embankment dike and to establish the reinforce region and technique through the embankment dike.

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Seismic Performance Evaluation of Flat Column Dry Wall System and Wall Slab System Structures (무량복합 및 벽식 구조시스템의 내진성능평가)

  • Kang, Hyungoo;Lee, Minhee;Kim, Jinkoo
    • Journal of the Computational Structural Engineering Institute of Korea
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    • v.25 no.3
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    • pp.259-266
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    • 2012
  • In this paper the seismic performance of a flat plate wall system structure was evaluated based on the ATC-63 approach, and the results were compared with those of a wall slab structure having the same size. As analysis model structures, a twelve story flat plate wall structure and a wall slab structure were designed based on the KBC-2009, and their seismic performances and collapse behaviors were evaluated by nonlinear static and incremental dynamic analyses(IDA). It was observed that the flat plate wall structure was designed with smaller amount of reinforced concrete, and showed slightly larger displacement response compared with those of the wall slab structure. The collapse margin ratios of the two structures obtained from the incremental dynamic analyses satisfied the limit states specified in the ATC-63, and the structures turned out to have enough capacity to resist the design level seismic load.

Comparison Study for Analgesic Effects of Electroacupuncture on Surgical Ankle Sprain Model Classified as Grade 3 in Rats (수술적 방법으로 유도된 3단계 고도(高度) 발목염좌 모델에서 혈위(穴位)에 따른 전침효과의 비교)

  • Yang, Seung-Bum;Sohn, In-Chul;Lee, Sung-Ho;Cho, Sang-Hoon;Kim, Jaehyo
    • Korean Journal of Acupuncture
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    • v.30 no.1
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    • pp.47-55
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    • 2013
  • Objectives : The purpose of this study was to determine whether electroacupuncture(EA) is effective in reducing pain on the severe ankle sprain classified as grade 3 in rats. Methods : The severe(grade 3) ankle sprain model was induced surgically by ankle ligament injury(the anterior talofibular, the calcaneofibular and the posterior talofibular) in the Sprague-Dawley rats(180~250 g). The effects of EA on weight bearing forces(WBR) of the affected foot were examined in a rat model of ankle sprain. EA was applied to either SI6, ST37, GB34, GB39 or GB42 acupoints by trains of electrical pulses(2 Hz, 1 ms pulse width, 2 mA intensity) for 15 min. Results : Cutting of the lateral ankle ligament complex produced the severe ankle sprain symptoms as grade 3. EA of the contralateral SI6 resulted in more analgesic effect than one of ipsilateral SI6 even though there was significant effect. EA of the ipsilateral GB34 and GB39 produced potent analgesic effects on the surgical ankle sprained pain behaviors. However, there were no significant analgesic effects in the contralateral GB34 and GB39 EA groups. In addition, both side of ST37 and GB42 did not result in analgesic effect on the surgical ankle sprained rat. Conclusions : The data suggest that EA induced analgesia shows point specificity on the severe ankle sprained pain model classified as grade 3.

Germination Characteristics of Taraxacum ohwianum Kitam. (산민들레 종자의 발아특성 연구)

  • Shin, So Lim;Lim, Yun Kyung;Kwon, Hyuk Joon;Kim, Soo Young
    • Korean Journal of Medicinal Crop Science
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    • v.24 no.3
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    • pp.177-182
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    • 2016
  • Background: Many Taraxacum spp. plants are widely used in medicine, but some of them have propagation problems, such as strong dormancy and poor germination rates. This study investigated the effects of temperature, gibberellic acid ($GA_3$), and potassium nitrate ($KNO_3$) on seed germination in Taraxacum ohwianum. Methods and Results: The seeds (NIBRGR0000135524) were exalbuminous, and their length and width were $4.54{\pm}0.032mm$ and $0.97{\pm}0.029mm$, respectively. Various germination temperatures were tested (15, 20, 25, and $30^{\circ}C$), the optimum temperature for germination was found to be $20^{\circ}C$ (31.3%). High temperature ($30^{\circ}C$) resulted in non-typical seedlings (thickened and crumpled cotyledons, with a restricted root system). To increase the germination capacity, $GA_3$ (200, 500, and $1,000mg/{\ell}$) or $KNO_3$ (20, 50, 100, 200, and $500mg/{\ell}$) solutions were used as pre-soaking solutions instead of water. The $GA_3$ treatments increased the germination percentage and rate, but germination percentage was higher with the $KNO_3$ treatments. Under the $50-200mg/{\ell}\;KNO_3$ treatments, the germination percentage exceeded 80% after 12 days, and $50mg/{\ell}\;KNO_3$ was notably effective (91.2% after 15 days). Conclusions: T. ohwianum seeds showed improved germination at low temperatures. The best method for germination was presoaking in $50mg/{\ell}\;KNO_3$ for 24 h, in the dark at $4^{\circ}C$, and then incubating the germinated seed at $20^{\circ}C$ for 15 days.

Effect of Pollutant Loading and Flow Distance to Wastewater Treatment Efficiency in the Constructed Wetland System (오염부하량 및 유하거리가 인공습지에 의한 폐수처리 효율에 미치는 영향)

  • 김형중;김선주;윤춘경
    • Magazine of the Korean Society of Agricultural Engineers
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    • v.39 no.5
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    • pp.97-108
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    • 1997
  • Natural wastewater treatment systems using the constructed wetland system were evaluated for the wastewater from the industrial complex in rural areas. For the treatment of wastewater from the industrial complex in rural area, a pilot plant of the constructed wetland system was installed at Baeksuk agri-industrial complex in ChunahnCity, Chunchungnam-Do. The experiment with this pilot plants was performed for 1996 and 1997. Results of the study were summarized as follows. For the BOD and COD, when the pollutant loading of them was about 1 3.8g/$m^2$. day (the concentration was l24.0mg/${\ell}$) arid 24.4g/$m^2$.day(the concentration was 220.Omg/${\ell}$), the removal rate of them was high, 90.2% and 93.4%, respectively. For the SS, the effluent concentration was consistently lower than the water quality standard even though the influent concentration varied significantly, which showed that SS was removed by the system effectively which consist of soil and plants. For the T-N and T-P, when the influent pollutant loading of them were moderately high, 2.8g/$m^2$.day to 7.4g/$m^2$. day(concentration 25.0mg/${\ell}$ to 49.7mg/${\ell}$) for T-N and 1.0g/$m^2$.day to 2.6g /$m^2$.day(concentration 8.6mg/${\ell}$ to 14.7mg/${\ell}$) for T-P, the removal rate of them were 86.5% and 94.0%, respectively. The removal rate by the flow distance increased rapidly in the first 4m from the inlet zone, and gradually there after. The width of system was 2m. Overall, the result showed that constructed wetland system is a feasible alternative for the treatment of wastewater from industrial complex in rural areas. Compared to existing systems, this system is quite competitive because it requires low capital cost, almost no energy and maintenance, and therefore, very cost effective.

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Micropatterning on Biodegradable Nanofiber Scaffolds by Femtosecond Laser Ablation Process (펨토초 레이저 절삭 공정을 이용한 생분해성 나노섬유 표면 미세 패터닝 공정)

  • Chung, Yongwoo;Jun, Indong;Kim, Yu-Chan;Seok, Hyun-Kwang;Chung, Seok;Jeon, Hojeong
    • Journal of Surface Science and Engineering
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    • v.49 no.6
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    • pp.555-559
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    • 2016
  • A biodegradable nanofiber scaffolds using electrospining provide fibrous guidance cues for controlling cell fate that mimic the native extracellular matrix (ECM). It can create a pattern using conventional electrospining method, but has a difficulty to generate one or more pattern structures. Femtosecond(fs) laser ablation has much interested in patterning on biomaterials in order to distinguish the fundamental or systemic interaction between cell and material surface. The ablated materials with a short pulse duration using femtosecond laser that allows for precise removal of materials without transition of the inherent material properties. In this study, linear grooves and circular craters were fabricated on electrospun nanofiber scaffolds (poly-L-lactide(PLLA)) by femtosecond laser patterning processes. As parametric studies, pulse energy and beam spot size were varied to determine the effects of the laser pulse on groove size. We confirmed controlling pulse energy to $5{\mu}J-20{\mu}J$ and variation of lens maginfication of 2X, 5X, 10X, 20X created grooves of width to approximately $5{\mu}m-50{\mu}m$. Our results demonstrate that femtosecond laser processing is an effective means for flexibly structuring the surface of electrospun PLLA nanofibers.

Region Separateness-based Edge Detection Method (영역의 분할정도에 기반한 에지 검출 기법)

  • Seo, Suk-T.;Jeong, Hye-C.;Lee, In-K.;Kwon, Soon-H.
    • Journal of the Korean Institute of Intelligent Systems
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    • v.17 no.7
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    • pp.939-944
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    • 2007
  • Edge is a significant element to represent boundary information between objects in images. There are various edge detection methods, which are based on differential operation, such as Sobel, Prewitt, Roberts, Canny, Laplacian, and etc. However the conventional methods have drawbacks as follow : (i) insensitivity to edges with gentle curve intensity, (ii) detection of double edges for edges with one pixel width. For the detection of edges, not only development of the effective operators but also that of appropriate thresholding methods are necessary. But it is very complicate problem to find an appropriate threshold. In this paper, we propose an edge detection method based on the region separateness between objects to overcome the drawbacks of the conventional methods, and a thresholding method for the proposed edge detection method. We show the effectiveness of the proposed method through experimental results obtained by applying the proposed and the conventional methods to well-known test images.

Comparative Analysis of LPF and HPF for Roads Edge Detection from High Resolution Satellite Imagery (고해상도위성영상에서 도로 경계 검출을 위한 고주파와 저주파 필터링 비교분석에 관한 연구)

  • Choi, Hyun;Kang, In-Joon
    • Journal of Korean Society for Geospatial Information Science
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    • v.14 no.3 s.37
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    • pp.3-11
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    • 2006
  • The need for edge detection about topography data from the high resolution satellite imagery is happening with increasing frequency according to many people utilize the its imagery as various fields recently. Many experts is recognizing of other GIS will make use of the road detection from the high resolution satellite imagery, including ITS (Intelligent Transportation Systems) and urban planning. This paper is comparative analysis of LPF (Low Pass Filtering) and HPF (High Pass Filtering) for roads edge detection from high resolution satellite imagery. As a result, LPF and HPF can be highlight selective pixels at edge area about input data. In case or applying to other techniques such as LPF for the same purpose, they aye more effective for wide road width which often cause the slight distortion of boundary or overall change of brightness values on the whole Image. Whereas, HPF has ability to enhance selectively detailed components in a target image.

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Feature Extraction of Welds from Industrial Computed Radiography Using Image Analysis and Local Statistic Line-Clustering (산업용 CR 영상분석과 국부확률 선군집화에 의한 용접특징추출)

  • Hwang, Jung-Won;Hwang, Jae-Ho
    • Journal of the Institute of Electronics Engineers of Korea SP
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    • v.45 no.5
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    • pp.103-110
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    • 2008
  • A reliable extraction of welded area is the precedent task before the detection of weld defects in industrial radiography. This paper describes an attempt to detect and extract the welded features of steel tubes from the computed radiography(CR) images. The statistical properties are first analyzed on over 160 sample radiographic images which represent either weld or non-weld area to identify the differences between them. The analysis is then proceeded by pattern classification to determine the clustering parameters. These parameters are the width, the functional match, and continuity. The observed weld image is processed line by line to calculate these parameters for each flexible moving window in line image pixel set. The local statistic line-clustering method is used as the classifier to recognize each window data as weld or non-weld cluster. The sequential procedure is to track the edge lines between two distinct regions by iterative calculation of threshold, and it results in extracting the weld feature. Our methodology is concluded to be effective after experiment with CR weld images.