• 제목/요약/키워드: true length

검색결과 172건 처리시간 0.026초

라인방식 디지털 항공 카메라영상의 위치 정확도 평가 (Accuracy Assessment Geoposition of Airborne Line-Scanner Image)

  • 조한근;위광재;최윤수;이상진
    • Spatial Information Research
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    • 제19권1호
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    • pp.51-59
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    • 2011
  • 라인빙식의 항공디지털 카메라인 ADS 80의 후방(backward)영상으로 정사영성을 제작하고 건물의 기복 변위와 폐색영역을 보정 후, True Ortho Photo을 제작하였다. 또한 제작된 정사영상과 True Ortho-Photo을 검증을 위해 지상검사점, 사진기준점을 이용하여 평면 위치정확도 평가 및 분석한 결과, 프레임방식과 비교하여 상대적으로 소량의 지상기준점을 이용하여 고품질의 정사영상을 제작할 수 있었다. 또한 라인 방식 카메라의 True Ortho Photo 제작 시, 종중복도가 100%이므로 폐색영역 보정시에 효과적임을 검증 할 수 있었다.

아미노산 엽면 시비가 멜론 묘의 생육에 미치는 영향 (Effect of the Foliar Application of Amino Acid Mixture on the Growth of Melon Seedlings)

  • 김영식;김혜진
    • 생물환경조절학회지
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    • 제11권2호
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    • pp.74-80
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    • 2002
  • 아미노산 엽면 시비가 멜론 묘의 생육에 미치는 영향에 대하여 연구하였다. 처리 시기는 본엽 1매 전개시(Ll)와 2매 전개시(L2)로 나누었고, 아미노산 농도는 무처리구, 10, 20, 30 mg . L$^{-1}$로 설정하였다. Ll에서 생체중과 건물중은 아미노산 처리구에서 높았다. 초장은 3차 조사시에 Ll-30에서 가장 높게 나타났다. L2에서 3차 조사시 생체중은 L2-30처리구에서 높게 나타났다. 초장은 2차와 3차 조사시 L2-30에서 높게 나타났다. 제1본엽의 염장과 엽폭의 경우, Ll의 3차 조사시 처리 효과가 나타났다. L2에서 염장은 처리구간에 유의적인 차이를 보이지 않았고, 엽폭은 3차 조사시에 아미노산 처리구에서 높게 나타났다 제2본엽의 염장과 엽폭은 Ll의 2차와 3차 조사시에 아미노산 처리구들에서 높게 나타났다. L2에서는 처리구간에 유의적인 차이를 보이지는 않았다 제7본엽의 염장과 엽폭은 시비 및 조사 시기에 관계없이 처리간에 유의성을 보이지는 않았다. 이상의 결과, 제1본엽이 전개된 후 아미노산의 농도를 20mg. L$^{-1}$ 이상, 회수를 3회 이상 엽면살포 하거나, 제2본엽이 전개된 후 아미노산을 시비할 경우에는 아미노산 농도를 30 mg . L$^{-1}$으로 설정하고 회수를 2회 이상 시비한다면 생육이 향상된 묘를 생산할 수 있을 것으로 사료된다.

Circular Skirt의 구성방법에 따른 Drape효과에 관한 연구 (A Study on the Effect of Drape by the Construction Method of th eCircular Skirt)

  • 홍정민
    • 복식
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    • 제33권
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    • pp.217-228
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    • 1997
  • The purpose of this study was to investigate influence of the construction method of the circular skirt on drapability and shape of static silhouette and length variation. In made 24 types of skirts giving the variations (six kinds of peach skin-like finished fabrics two types of cutting method two types of machine stitch method of hem), The results were as follows: 1. Analysis of drapability In the cutting method thre was similarity between warp direction and true bias direc-tion. In the machine stitch method of hem there was similarity between blind stitch and blind stitch machine. According to the fabrics analysis of drapability was excellent in the order N/P 80/20(fabric 1)>P 100(fabric 5)>P 100(fabric 6)>P 100 (fabric 2)>P 100 (fabric 4)>N/C 50/50(fabric 3). 2. Analysis of the characteristics values of static silhouette shape In the cutting method shape of static sil-houette became wide in the warp direction. In the machine stitch method of hem shape of static silhouette became wide in the blind stitch. According to the fabrics shape of static silhouette became most wide in the N/C 50/50(fabric 3) and shape of static sil-houette become most narrow in the P 100(fabric 2,5) 3. Analysis of the length variation In the cutting method the true bias direc-tion was longer than the warp direction. In the machine stitch method of hem there was simi-machine stitch method of hem there was simi-larity between blind stitch and blind stitch ma-chine. In fabrics the P 100(fabric 6) showed the longest the N/C 50/50(fabric 3) showed most slight. Interaction between the cutting and messure-ment part of skirt lengh. In the warp diretion parts that showed longest length variation were C. G, K, O in the true bias diretion parts that showed most slight length variation were A, E, M, I.

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굽힘하중을 받는 배관의 파손에 미치는 감육의 영향 (Effect of Wall Thinning on the Failure of Pipes Subjected to Bending Load)

  • 안석환;남기우
    • 대한기계학회논문집A
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    • 제29권4호
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    • pp.606-613
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    • 2005
  • Effects of circumferentially local wall thinning on the fracture behavior of pipes were investigated by monotonic four-point bending. Local wall thinning was machined on the pipes in order to simulate erosion/corrosion metal loss. The configurations of the eroded area included an eroded ratio of d/t= 0.2, 0.5, 0.6, and 0.8, and an eroded length of ${\ell}\;=10mm,$ 25mm, and 120mm. Fracture type could be classified into ovalization, local buckling, and crack initiation depending on the eroded length and eroded ratio. Three-dimensional elasto-plastic analyses were also carried out using the finite element method, which is able to accurately simulate fracture behaviors excepting failure due to cracking. It was possible to predict the crack initiation point by estimating true fracture ductility under multi-axial stress conditions at the center of the thinned area.

True VoD 서비스를 위한 더블 패칭 기법의 최적화 (Optimization of a Double Patching Technique for True Video-on-Demand Services)

  • 하숙정;김진규
    • 한국산업정보학회논문지
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    • 제13권1호
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    • pp.46-56
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    • 2008
  • 더블 패칭은 VoD 시스템을 위한 멀티캐스트 기법으로 클라이언트에게 정규 스트림뿐만 아니라 긴 패칭 스트림도 공유하게 하여 true VoD 서비스를 제공하기 위해 제안되었다. 이 기법은 뒤이어 발생하는 짧은 패칭 스트림들을 위해 긴 패칭 스트림이 항상 패칭 창의 두 배 기간 동안 재생될 여분의 데이터를 갖도록 한다. 본 논문에서는 마지막 짧은 패칭 스트림의 시작 시간을 이용하여 긴 패칭 스트림의 패칭 창이 끝날 때 긴 패칭 스트림에 포함된 쓸모없는 데이터를 제거하여 더블 패칭을 최적화하는 기법을 제안한다. 서버가 true VoD 서비스를 제공하기 위해 필요한 평균 대역폭 요구량을 성능 척도로 사용하여, 요청 도착 간격, 클라이언트의 로컬 버퍼 크기, 비디오 길이가 평균 대역폭 요구량에 미치는 영향을 평가한다. 성능 평가 결과는 제안한 기법이 모든 경우에 더블 패칭을 최적화함을 보여 준다.

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뉴미디어 시대 속 '참교육' 콘텐츠와 현대인의 의식구조 (Contents of 'true education' in the Era of New Media and the Consciousness Structure of Modern People)

  • 김세연
    • 한국콘텐츠학회논문지
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    • 제22권4호
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    • pp.468-478
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    • 2022
  • 전교조 핵심 이념이었던 '참교육'은 뉴미디어 시대의 자장 안에서 재전유된다. 젊은층을 중심으로 활발히 사용되는 이 단어는 '사회적 비난의 대상이 되는 사람 대한 응징'을 뜻한다. 최근 인터넷에서 흔히 볼 수 있는 '참교육 콘텐츠'의 특징으로는 첫째, '단편화' 경향을 보인다는 점이다. 참교육 콘텐츠들은 분량이 짧고, 내용이 매우 지엽적이다. 이는 총체성이 사라지고 작은 이야기들을 소비하는 포스트모던 사회의 특징을 반영한다. 둘째, 선악을 가르는 기준이 지극히 '자의적'이라는 것이다. 기존 권선징악 서사들은 사랑·배려·평화 등 어느 정도 보편적인 가치를 지니고 있었던 데 비해, 참교육 콘텐츠는 지극히 편협한 시선으로 선악을 구분한다. 자의적 기준에 대한 정당성을 얻기 위해 택하는 방법은 공공의 분노를 부추기는 것이다. 셋째, '유머'가 가미되어 있다는 점이다. 여기서 유머는 혐오의 정서와 결합하며, 사람들의 비판의식을 약화시킨다는 문제를 야기한다.

광섬유를 이용한 위상 배열 안테나 (Optically Driven Phased Array Antenna)

  • 김태선;서철헌
    • 대한전기학회:학술대회논문집
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    • 대한전기학회 1998년도 추계학술대회 논문집 학회본부 C
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    • pp.981-983
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    • 1998
  • In this paper, we present theoretical designs for a beam steering phased array antenna that uses a true time delay optical feeder. A variable true time delay is achieved by employing one tunable laser source and high dispersion fibers with different length. The wavelength tunable optical carrier propagation in a high-dipersion fiber realizes a true time delay, with the steering direction set by a single voltage controlling the wavelength. Beamsteering of a phased array antenna is obtained by controlling the tunable laser source. An employment of a high dispersion fiber response shows wide-band operation of beem steering antenna system.

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근관장 측정에 있어서 디지털 영상 처리기와 주파수 의존형 측정기의 정확도 (The Accuracy of the Digital Imaging System and the Frequency Dependent Type Apex Locator in Root Canal Length Measurement)

  • 이병립;박창서
    • 치과방사선
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    • 제28권2호
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    • pp.435-459
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    • 1998
  • In order to achieve a successful endodontic treatment, root canals must be obturated three-dimensionally without causing any damage to apical tissues. Accurate length determination of the root canal is critical in this case. For this reason, I've used the conventional periapical radiography, Digora/sup (R)/(digital imaging system) and Root ZX/sup (R)/(the frequency dependent type apex locator) to measure the length of the canal and compare it with the true length obtained by cutting the tooth in half and measuring the length between the occlusal surface and the apical foramen. From the information obtained by these measurements, I was able to evaluate the accuracy and clinical usefulness of each systems. whether the thickness of files used in endodontic therapy has any effect on the measuring systems was also evaluated in an effort to simplify the treatment planning phase of endodontic treatment. 29 canals of 29 sound premolars were measured with #15, #20, #25 files by 3 different dentists each using the periapical radiography. Digora/sup (R)/ and Root ZX/sup (R)/. The measurements were then compared with the true length. The results were as follows: 1. In comparing mean discrepancies between measurements obtained by using periapical radiography(mean error: -0.449±0.444 mm), Digora/sup (R)/(mean error: -0.417±0.415 mm) and Root ZX/sup (R)/(mean error: 0.123±0.458 mm) with true length. periapical radiography and Digora/sup (R)/ system had statistically significant differences(p<0.05) in most cases while Root ZX/sup (R)/ showed none(p>0.05). 2. By subtracting values obtained by using periapical radiography, Digora/sup (R)/ and Root ZX/sup (R)/ from the true length and making a distribution table of their absolute values. the following analysis was possible. In the case of periapical film. 140 out of 261<53.6%) were clinically acceptable satisfying the margin of error of less than 0.5 mm. 151 out of 261 (53,6%) were acceptable in the Digora/sup (R)/ system while Root ZX/sup (R)/ had 197 out of 261(75.5%) within the limits of 0.5mm margin of error. 3. In determining whether the thickness of files has any effect on measuring methoths, no statistically significant differences were found(p>0.05). 4. In comparing data obtained from these methods in order to evaluate the difference among measuring methods, there was no statistically significant difference between periapical radiography and Digora/sup (R)/ system(p>0.05), but there was statistically significant difference between Root ZX/sup (R)/ and periapical radiography(p<0.05). Also there was statistically significant difference between Root ZX/sup (R)/ and Digora/sup (R)/ system(p<0.05). In conclusion, Root ZX/sup (R)/ was more accurate when compared with the Digora/sup (R)/ system and periapical radiography and seems to be more effective clinically in determining root canal length. But Root ZX/sup (R)/ has its limits in determining root morphology and number of roots and its accuracy becomes questionable when apical foramen is open due to unknown reasons. Therefore the combined use of Root ZX/sup (R)/ and the periapical radiography are mandatory. Digora/sup (R)/ system seems to be more effective when periapical radiographs are needed in a short period of time because of its short processing time and less exposure.

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Hough Transform 정보로부터 입력 직선의 위치와 실제 길이 정보 추출 (Extracting the Position and the True Length of the Input-Line from Hough Transform data)

  • 김기정;박상국;김종윤;박세준;배장근;김수중
    • 대한전자공학회:학술대회논문집
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    • 대한전자공학회 1999년도 하계종합학술대회 논문집
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    • pp.301-304
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    • 1999
  • In this paper, we proposed the new method of extracting the position and the length of the input-line by using only two parameters ($\theta$, $\rho$) from the HT(Hough Transform) data. The computer simulations and the optical experiments by using the HT CGH(Computer Generated Hologram) filter is perfermed. The results are very similar to those of the computer simulation results.

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파노라마촬영장치의 협설선형단층상에 의한 상악동과 치조골 평가 (An assessment of maxillary sinus and alveolar bone in cross-sectional linear tomogram of panorama)

  • 김재덕
    • Imaging Science in Dentistry
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    • 제33권3호
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    • pp.137-141
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    • 2003
  • Purpose: To evaluate the precision of measurements taken of dental implants in bucco-lingually sectioned views of the maxilla by linear tomograms of the panorama and to assess the visibility of the inferior wall of the maxillary sinus. Materials and Methods : Eighty sites prepared with implants of gutta percha cone in the sockets of the upper premolars and molars of 10 dry skulls were radiographically examined using linear tomograms of panorama, and scanned coronally and axially by computed tomography. The differences in mm between the measurements in bucco-lingually sectioned images of maxillary alveolar bone and the true length and width of the implanted gutta percha cones were compared as mean values (mean) and standard deviations (SD) for each radiographic technique. Linear tomography of panorama was compared with computed tomography for visualization of the relationship between the inferior wall of maxillary sinus and the end of each implant. Results: The deviations between the actual implant length and the measured values taken from the linear tomograms (0.44±0.39 mm) was significantly less than the measured values from the multiplanar reconstructed images of the axially scanned computed tomogram (1.21 ± 0.90 mm). There was statistically significant difference (p < 0.05) between two techniques in the differences between the measurements and true implant length. The relationship of the inferior border of maxillary sinus with end of implant was worse identified with the linear tomogram of panorama (68%) than the multiplanar reconstructed image of axially scanned computed tomogram (99%). Conclusion: We could not find any differences in the accuracy of length measurement between the linear tomogram of panorama and computed tomogram, but computed tomogram allowed for a better visualization of the inferior wall of the maxillary sinus than the linear tomogram.

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