• Proceedings of the KSRS Conference
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• 2008.10a
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• pp.37-40
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• 2008

The purpose of this paper is to extract DEMs from Spot-3 strips using orbit modeling technique. Spot-3 stereo strip images along 420km in distance were used for experiments. The orbit modeling technique has been suggested to establish accurate geometric models for a whole strip taken on the same orbit using only a small number of GCPs on the top area of the strip. This method enables extraction of orientation parameters of the scene along the strip that is needed to generate DEMs. Consequently, we were able to extract DEMs over the areas without accurate GCPs obtained by GPS surveying per each scene. Assessment of accuracy was carried out using USGS DTED. DEMs generated from the orbit modelling technique suggested showed satisfactory performance when quantitative analysis of accuracy assessment was carried out.

• Journal of Korean Academy of Fundamentals of Nursing
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• v.19 no.4
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• pp.444-452
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• 2012

Purpose: To explore the usefulness of previous fall history as a triage variable for inpatients. Methods: Medical records of 21,382 patients, admitted to medical units of one tertiary hospital, were analyzed retrospectively. Inpatient falls were identified from the hospital's self-report system. Non-falls in 1,125 patients were selected by a stratified matching sampling with 125 patients with falls (0.59%). A comparative and predictive accuracy analysis was conducted to describe differences between the two groups with and without a history of falls. Logistic regression was used to measure the effect size of the fall history. Results: The fall history group showed higher prevalence by 9 fold than the non-fall history group. The relationships between falls and relevant variables which were significant in the non-fall history group, were not significant for the fall history group. Falls in the fall history group were 25 times more likely than in the non-fall group. Predictive accuracy of the risk assessment tool showed almost zero specificity in the fall history group. Conclusion: The presence of fall history, the fall prevalence, variables relevant to falls, and the accuracy of the risk tool were different, which support the usefulness of the fall history as a triage variable.

• Journal of Electrical Engineering and Technology
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• v.10 no.3
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• pp.1328-1334
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• 2015

A new system for evaluating the voltage management errors of distribution equipment is presented in this paper. The main concept of the new system is to use real distribution live-line voltage to evaluate and correct the voltage measurement data from distribution equipment. This new approach is suitable for a new Distribution Management System (DMS) which has been developed for a distribution power system due to the connection of distributed generation growth. The data from distribution equipment that is installed at distribution lines must be accurate for the performance of the DMS. The proposed system is expected to provide a solution for voltage measurement accuracy assessment for the reliable and efficient operation of the DMS. An experimental study on actual distribution equipment verifies that this voltage measurement accuracy assessment system can assess and calibrate the voltage measurement data from distribution equipment installed at the distribution line.

• Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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• v.20 no.2
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• pp.105-110
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• 2002

For the accuracy assessment of DTM obtained by Airborne Laser Mapping Systems (ALMS), we selected 500 m spaced test points and analyze the accuracy of the DTM by various methods including GPS survey. To estimate the height at the point in between the test points of the DTM we produced a TIN, and to analyze the accuracy we use a GPS coverage map overlaid with the TIN. Compared with the existing method, DTM by ALMS is shown to be relatively accurate, and therefore, ALMS is applicable to 1/5000 digital terrain mapping.

• Proceedings of the KSRS Conference
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• 2003.11a
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• pp.286-288
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• 2003

In this paper, we present our implementation of the direct camera model (image to ground) for SPOT5 and use it to assess the geometric accuracy of SPOT5 imagery. Our assessment confirms the location accuracy of SPOT5 imagery (without use of GCPs) is less than 50m. We further introduce a few attitude parameters to refine the camera model with GCPs. The model is applied to two SPOT5 supermode images, one near vertical, incidence angle of 3 degrees, and one far oblique, incidence angle of 27 degrees. The results show that accuracy (rms of check points) of about one pixel (2.5m) can be achieved with about 4 GCPs by using only 3 parameters to correct the yaw, pitch and roll of the satellite.

• Korean Journal of Human Ecology
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• v.9 no.4
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• pp.447-457
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• 2000

The purpose of this study was to examine the accuracy of consumer's self-assessment on actual diets and to analyze its accuracy by consumer's health status. The results were as follows: In general, many consumers misunderstood or assessed inaccurately their actual diets. In particular, the Extreme Optimists and the Optimists were the consumers whose diets were poor, but who assessed wrongly their actual diet quality. In relation with their health status, these two groups showed that the better the consumers consider their health, the more the Extreme Optimists and the Optimists are.

• Proceedings of the IEEK Conference
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• 2007.07a
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• pp.395-396
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• 2007

Bone age assessment has been widely used to measure the ossification in pediatric radiology. For the assessment, first bone age of each epiphyseal plate is estimated using DCT/LDA, then the bone age of a patient is calculated by using the median of 9 estimations. For some patients, however, due to various reasons such as X-ray image quality or the pose of fingers, it is common to miss couple of plates in automated systems. In this paper, we investigate the relationship between the number of detected plates and the accuracy of bone age assessment. In the experimental results, we confirmed the similarity between bone age assessed using more than 7 epiphyseal plates and that assessed using 9 epiphyseal plates.

• Proceedings of the Korean Society of Surveying, Geodesy, Photogrammetry, and Cartography Conference
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• 2004.04a
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• pp.259-262
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• 2004

There is the case to make the image map by using color aerial photo, DEM gives the accuracy of the Ortho image. Therefore We evaluate the accuracy by digital photogrammetric system after generating the DEM of Color Aerial Image.

• Journal of Environmental Impact Assessment
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• v.7 no.2
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• pp.27-35
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• 1998

In Korea, the initial installation of GIS requires lots of cost, time, and human efforts. If the accuracy of GIS data does not meet the certain standard for use, the system may not work as expected. So, it needs to be investigated for the accuracy of raw data. However, there is little study for the accuracy of raw data in Korea. Therefore, the purpose of this study is to review the data accuracy of raw data - geologic map, 1:5,000 and 1:25,000 scale topographic map, forest stand map, degree of green naturality(DGN) map, and detailed survey data of DGN map-, which are to be used in Environmental Information System(EIS) in Korea. After this study, some errors in data were surveyed and following conclusions were derived. (1) There is no map data, e. g, wildlife habitat map. (2) Some data are misinterpreted depending on the location in the geologic map. (3) Some data are not updated properly after change of topography in the topographic map or the elevation and location is different depending on the scale.. (4) Some data are not edited properly in the forest stand map, e. g. two attributes in one polygon. (5) DGN classification system does not reflect the characteristic of Korean vegetation community. So, it needs to be refined and restructured.

• Journal of Korean Society for Geospatial Information Science
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• v.14 no.4 s.38
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• pp.19-26
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• 2006

This study assessed the accuracies of the ground information extracting methods from the LiDAR data. Especially, it compared two kinds of method, one of them is using directly the raw LiDAR data which is point type vector data and the other is using changed data to DSM type as the normal grid type. The methods using Local Maxima and Entropy methods are applied as a former case, and for the other case, this study applies the method using edge detection with filtering and the generated reference surface by the mean filtering. Then, the accuracy assessment are performed with these results, DEM constructed manually and the error permitted limit in scale of digital map. As a results, each DEM mean errors of methods using edge detection with filtering, reference surface, Local Maxima and Entropy are 0.27m, 2.43m, 0.13m and 0.10m respectively. Hence, the method using entropy presented the highest accuracy. And an accuracy from a method directly using the raw LiDAR data has higher accuracy than the method using changed data to DSM type relatively.