• Journal of the Korean Society of Environmental Restoration Technology
• /
• v.11 no.2
• /
• pp.1-9
• /
• 2008

The objective of the study is 10 know the relation of landslide occurrence with using TPI (Topographic Position Index) in the Pyungchang County. Total 659 landslide scars were detected from aerial photographs. To analyze TPI, 100m SN (Small-Neighborhood) TPI map, 500m LN (Large-Neighborhood) TPI map, and slope map were generated from the DEM (Digital Elevation Model) data which are made from 1 : 5,000 digital topographic map. 10 classes clustered by regular condition after overlapping each TPI maps and slope map. Through this process, we could make landform classification map. Because it is only to classify landform, 7 classes were finally regrouped by the slope angle information of landslide occurrence detected from aerial photography analysis. The accuracy of reclassified map is about 46%.

• 한국연소학회:학술대회논문집
• /
• 2000.05a
• /
• pp.16-25
• /
• 2000

The differential diffusion of two species in jet is considered. The direct photo images of $H_{2}/SF_{6}$ flame are taken and the non-react jets of $H_{2}/SF_{6}$ mixture are visualized with Rayleigh scattering method. The structures of Dual flame are found in the photography. As the volume fraction of $H_2$ in mixture is increased, the flame at side is long and as the volume fraction of $SF_{6}$ in mixture is increased, the flame at center is long. This phenomena are deduced from the non-react mixture using Rayleigh scattering method. Result show that the volume fraction in the mixture is important in differential diffusion.

• Journal of radiological science and technology
• /
• v.21 no.2
• /
• pp.57-63
• /
• 1998

AEC was designed to assist in the production of radiographs of equal density and to aid in the production f consistently high quality radiographs. Many improvements have been made in the AEC and these have helped to increase it's acceptance. Newer system (Falling load) control kVp and mA as well as exposure time. Authors have had experiments about the characteristics of AEC by Zone System. Zone System is the method to detection of photographic image qualify by control the photo print from Fred Archer and Ansel Adams. With the Zone System theory the experiments of density control, characteristics of phantom thickness and reproducibility of occupation rate of contrast media could make quality control of X-ray photography effectively in falling load system.

• Journal of Information Display
• /
• v.3 no.1
• /
• pp.22-26
• /
• 2002

Three-dimensional dynamic display system based on computer-generated integral imaging is discussed and its feasibility is verified via some basic experiments. Integrated images observed from different viewing points are seen to have full parallax and the animated 3D image was implemented successfully. Moreover, using large size Fresnel lens array was found to helps widen viewing angle and to make the system more practical.

• KSCE Journal of Civil and Environmental Engineering Research
• /
• v.2 no.1
• /
• pp.81-92
• /
• 1982

This study aimes at understanding the factors influencing poistion-determination by investigating the propagation of errors developed during orientation work in three-dimmensional coordinates of the aerial photograph. This paper treats the comparison and analysis of phopagation of errors due to computing orientation requited for the analysis of the absolute coordinate from the image coordinates of photograph.

• Journal of Korean Society for Geospatial Information Science
• /
• v.13 no.3 s.33
• /
• pp.3-13
• /
• 2005

This study aims to establish the quality management method for spatial data construction process. Total 17 regulations related to spatial database construction and major aerial survey firms were analyzed in terms of working process, equipments, accuracy of results. It is standardized the process of making new digital maps using aerial photography, revising existing digital maps, producing digital elevation models and developing imagery maps. Quality checking factors for spatial data construction process are also established.

• Proceedings of the KSME Conference
• /
• 2002.08a
• /
• pp.287-290
• /
• 2002

'Backhole' is an extra empty volume where is located behind the tangential entries at the rear par of the vortex chamber in the swirl coaxial injector. With the backhole, there are three major hydraulic characteristics. First, mass flow rate is increased about $15{\%}$ compared with the case without the backhole. Second, with the backhole, the center region of the injected flow has more large volume than that of without the backhole. The last, some range of the cone angle can be controlled by the backhole Experiments are conducted by using a PDPA apparatus, a mechanical patternator, stroboscopic photography and etc. With the backhole, based on cold-flow tests, the model swirl injector has some Improvement in its performance.

• Proceedings of the KSLP Conference
• /
• 1994.06a
• /
• pp.110-116
• /
• 1994

보통사람의 성대는 일상회화중 1초에 100∼300번의 진동을 하며 노래를 하는 경우는 1,000번 이상도 진동하게 되므로 우리의 유안으로는 그 자세한 진동상태를 관찰할 수가 없어 특수한 기기를 사용해야만 한다. 현재로서 사용되는 특수기기로는 후두스트로보스코피(laryngostroboscopy), 초고속영화법(ultra high speed photography), 그로토그라피(glottography) 및 카이모그라피(kymography) 등이 있다. 이 중 초고속영화법은 1초에 3,000회 이상의 성대진동을 촬영할 수 있어 연구 및 교육에 대단히 유용한 기기이나 가격이 비싸고 그 data를 분석하는데 시간이 많이 걸려 일반임상검사로서는 부적당하며 그로토그라피는 성대자체를 직접 관찰하는 것이 아니고 그 관측결과를 그래프로 나타내주는 기기로서 에에는 초음파, 광전 및 전기를 이용한 방법등이 있다. (중략)

• Laser Solutions
• /
• v.6 no.2
• /
• pp.9-17
• /
• 2003

Due to the heat confinement in the shallow region of the target for a short time scale, pulsed laser annealing has received an increasing interest for the fabrication of poly-Si thin film transistors(TFTs) on glass as a low cost substrate in the flat panel displays. The formation and growth mechanisms of poly silicon(poly-Si) grains in thin films are investigated using an excimer laser crystallization system. To understand the crystallization mechanism, the grain formations are observed by FESEM photography. The optical reflectance and transmittance during the crystallization process are measured using HeNe laser optics. A two-step ELC(Excimer Laser Crystallization) process is applied to enhance the grain formation uniformity.

• Laser Solutions
• /
• v.11 no.3
• /
• pp.16-20
• /
• 2008

The lap Joint welding of 6K21 aluminum sheets by Nd:YAG laser were performed with an aluminum 5183 filler wire or without a filler wire. The porosity of laser welding beads were observed through an optical microscope and X-ray photography with various levels of welding speed and gap size. The porosity was observed in the gap between upper and lower sheet near a heat affected zone when autogenous welding. Decrease of welding speed and use of AA5183 filler wire reduced porosity significantly.