• Journal of Biomedical Engineering Research
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• v.28 no.5
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• pp.601-608
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• 2007

2 Dimensional Gel Electrophoresis(2DGE) is an essentialmethodology for analysis on the expression of various proteins. For example, information for the location, mass, expression, size and shape of the proteins obtained by 2DGE can be used for diagnosis, prognosis and biological progress by comparison of patients with the normal persons. Protein spot matching for this purpose is comparative analysis of protein expression pattern for the 2DGE images generated under different conditions. However, visual analysis of protein spots which are more than several hundreds included in a 2DGE image requires long time and heavy effort. Furthermore, geometrical distortion makes the spot matching for the same protein harder. In this paper, an iterative algorithm is introduced for more efficient spot matching. Proposed method is first performing global matching step, which reduces the geometrical difference between the landmarks and the spot to be matched. Thus, movement for a spot is defined by a weighted sum of the movement of the landmark spots. Weight for the summation is defined by the inverse of the distance from the spots to the landmarks. This movement is iteratively performed until the total sum of the difference between the corresponding landmarks is larger than a pre-selected value. Due to local distortion generally occurred in 2DGE images, there are many regions in whichmany spot pairs are miss-matched. In the second stage, the same spot matching algorithm is applied to such local regions with the additional landmarks for those regions. In other words, the same method is applied with the expanded landmark set to which additional landmarks are added. Our proposed algorithm for spot matching empirically proved reliable analysis of protein separation image by producing higher accuracy.

• Journal of the Korean Society of Radiology
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• v.5 no.5
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• pp.223-229
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• 2011

When negative electron in x-ray tube is accelerated in to a high speed and then the currency of the electron is blocked by the target, x-ray happens by the conversion of the energy. The real area where the fast accelerated electron collides to a target area is called actual focal spot. When the string focused size is observed at the central ray side, where the direction x-ray comes out, the size seems to be reduced. This focus is called effective focal spot. According to radiation angle of x-rays tube, the degree of the negative pole side presents higher value than inclination, the amount of exposed radiation that patient receives differs by the angle of positive pole, which means effective focal spot is the variable. This paper presents the correlation between size of effective focal spot and amount of exposed radiation to the patient by it, and effective research for homogenized dose dispersion by the size of effective focal spot. In conclusion, following the focal size, effective range which was -8cm ~ 0 cm on average, was found and average dose rate was 0.019 R/min. Through this range, for patients with small radiation exposure, image with good density and resolution in aspect of diagnosing will be able to be obtained.

• Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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• v.31 no.6_2
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• pp.559-565
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• 2013

Spatial resolution of land covers from remotely sensed images can be increased using super-resolution mapping techniques for soft-classified land cover proportions. A further development of super-resolution mapping technique is downscaling the original remotely sensed image using super-resolution mapping techniques with a forward model. In this paper, the model for increasing spatial resolution of remote sensing multispectral image is tested with real SPOT 5 imagery at 10m spatial resolution for an area in Bac Giang Province, Vietnam in order to evaluate the feasibility of application of this model to the real imagery. The soft-classified land cover proportions obtained using a fuzzy c-means classification are then used as input data for a Hopfield neural network (HNN) to predict the multispectral images at sub-pixel spatial resolution. The 10m SPOT multispectral image was improved to 5m, 3,3m and 2.5m and compared with SPOT Panchromatic image at 2.5m resolution for assessment.Visually, the resulted image is compared with a SPOT 5 panchromatic image acquired at the same time with the multispectral data. The predicted image is apparently sharper than the original coarse spatial resolution image.

• Proceedings of the KSRS Conference
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• 2003.11a
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• pp.1162-1164
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• 2003

The methods of the geometric reconstruction and sensor calibration of satellite linear pushbroom images are investigated. The model of the sensor used is based on the SPOT model that is developed by Kraiky. The satellite trajectory is a Keplerian trajectory in the approximation. Four orbit parameters, longitude of the ascending node(${\omega}$), inclination of the orbit plan(I), latitude argument of the satellite(W) and distance between earth center and satellite, are used for the camera modeling. Time-dependent orbit parameters are expressed by quadratic polynomials. SPOT-5 images have been used for validation tests. The results are that the RMSE acquired from 20 GCPs is 1.763m and the RMSE of 5 checking points 2.470m. Because the ground resolution of SPOT-5 is 2.5m, the result obtained in this study has a good accuracy. It demonstrates that the sensor model developed by this study can be used to reconstruct the geometry of satellite image using pushbroom camera.

• 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.

• Proceedings of the KSRS Conference
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• 2006.03a
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• pp.319-322
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• 2006

2002년 5월 촬영이 시작된 SPOTS 영상은 공간해상도가 2.5mX2.5m로 고해상도이면서도 촬영폭이 광역적이어서 다양한 활용이 가능하다. SPOT5영상을 보다 유용하게 활용하기 위해서는 단순 기하보정 보다는 높은 정확도를 얻을 수 있는 정사보정이 요구된다. 보정영상의 정확도에 영향을 미치는 요소로는 지형, GCP, DEM등이 있다. 본 연구에서는 다른 조건들은 동일하게 하고, 자료 구축에 많은 시간이 소요되는 DEM(수치표고모델)의 축척만을 달리하여 보정 영상의 정확도를 비교하였다. 그 결과 DEM의 축척 변화가 보정 영상에 미치는 영향은 미비한 것으로 나타났다. 따라서 작업의 효율성을 고려할 경우에 소축척의 DEM을 사용하는 것이 바람직하다.

• Tribology and Lubricants
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• v.19 no.5
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• pp.268-273
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• 2003

This paper presents hot spot behaviors on the rubbing surface of disk-pad type brake by using coupled thermal-mechanical analysis technique. The height of micro-asperity on the rubbing surface is usually 2∼3 ${\mu}$m in practical disk brakes. Non-uniform micro-contacts between the disk and the rigid friction pads lead to high local temperature distributions, which may cause the material degradation, and develop hot spots, thermal cracks, and brake system failure at the end for a braking period. The friction temperatures on the rubbing surface of disk brakes in which are strongly related to the hot spot and thermal related wears are rapidly concentrated on the micro-contact asperities during braking. The computed FEM results show that the contact stress, friction induced temperature and thermal strain are highly concentrated on the rubbing micro-contact asperities even though the braking speed and force are small during the braking period. This hot spot may directly produce the slippage and various thermal wears on the brake-rubbing surface.

• Journal of the Korean Society for Nondestructive Testing
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• v.25 no.3
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• pp.209-214
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• 2005

Spot welding is the most widely used in automotive and aerospace industries. The quality of weld depends upon the size of nugget between the overlapped steel plates. Recently, the thickness of the steel plates is much thinner and hence, it introduces the smaller size of nugget. Therefore, it is necessary not only to develop the criterion to evaluate the quality of weld but also to obtain the optimal welding conditions for the better performance. In this paper, the steel plates, 0.5 mm through 1.5 mm thickness, have been spot welded at different welding conditions and the nugget sizes are examined by ultrasonic technique (C-scan type). The relationships between the nugget sizes and the weldability have been investigated. The result of ultrasonic technique shows the good agreement with that of the tensile test.

• Asian-Australasian Journal of Animal Sciences
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• v.25 no.4
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• pp.592-596
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• 2012

The simple method of evaluating highly marbled beef was examined by image analysis. The images of the cross section at the 6 to 7th rib were obtained from 82 carcasses of Wagyu cattle. By using an overall trace method, the surrounding edges of the longissimus thoracis and three muscles were traced automatically and manually with image analysis. In a spot method, 3 to 5 locations (2.5 or 3.0 cm in diameter) for each muscle were rapidly selected with no manual trace. The images were flattened, binarized, and the ratio of fat area to muscle area was determined. The correlation coefficients for marbling between different muscles, and between the overall trace and the spot methods were 0.55 to 0.81 between different muscles and 0.89 to 0.97, respectively. These results suggested that the simple spot method is speedy and almost as useful as the overall trace method as a measuring technique for beef marbling in loin muscles, especially for highly marbled beef.

• Journal of the Korean Society of Manufacturing Technology Engineers
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• v.5 no.4
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• pp.38-46
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• 1996

This paper discusses the feasibility of Ultrasonic Nondestructive Evaluation (UNDE) technique for sport weld quality. Ultrasonic c-scan image assisted by image processing technique was used for Nondestructive Evaluation(NDE) of spot weld quality. Ultrasonic testing results obtained were confirmed and compared by Optical Microscope and SAM(Scanning Acoustic Mircroscope) observation of the spot-weld cross section, The results show that the nugget dinameter can be successfully measured with the accuracy of 0.5mm. It was ascertained that ultrasonic c-scan technique is very effective method for the sake of the approach to the quantitative measurement of nugget diameter and the discrimination of the corona bond from nugget. Additional support for the above conclusions is provided by the results for galvanized steel. The ultrasonic results for galvanized welds generally correspond to the results for uncoated steel. Finally, it was found that the above-mentioned technique can be sufficiently applied to NDE method for securing the Quality Assurance(QA) of spot welded products in production line.