• Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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• v.28 no.1
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• pp.161-168
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• 2010

This study aims to propose a method that shall rapidly acquire 3D information of the fast and frequently changing city areas by using the images taken by the UAV photogrammetric method, and to develop the process of the acquired data. For this study's proposed UAV photogrammetric method, low-cost UAV and non-metric digital camera were used. The elements of interior orientation were acquired through camera calibration. The artificial 3D model of the artificial structures was constructed using the image data photographed at the target area and the results of the ground control point survey. The digital surface model was created for areas that were changed due to a number of civil works. This study also analyzes the proposed method's application possibility by comparing a 1/1,000 scale digital map and the results of the ground control point survey. Through the above studies, the possibilities of constructing a 3D virtual city model renewal of 3D GIS database, abstraction of changed information in geographic features and on-demand updating of the digital map were suggested.

• Korean Journal of Remote Sensing
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• v.15 no.2
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• pp.119-130
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• 1999

At present, many ground stations all over the world are using NORAD orbit element data in order to track and communicate with Earth orbiting satellites. The North American Aerospace Defense Command (NORAD) observes thousands of Earth orbiting objects on daily basis and provides their orbital information via internet. The orbital data provided by NORAD, which is also called two line element (TLE) sets, allows ground stations to predict the time-varying positions of satellites accurately enough to communicate with the satellites. In order to complete the mission of a high resolution remote sensing satellite which requires very high positional determination and control accuracy, however, a mission control and tracking ground station is dedicated for the observation and positional determination of the satellite rather than using NORAD orbital sets. In the case of KITSAT-3, NORAD orbital elements are currently used for image acquisition planning and for the processing of acquired images due to the absence of a dedicated KITSAT-3 tracking ground system. In this paper, we tested and analyzed the accuracy of NORAD orbital elements and the appropriate prediction model to determine how accurately a satellite acquisites an image of the location of interest and how accurately a ground processing system can generate the catalog of the images.

• Environmental Analysis Health and Toxicology
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• v.18 no.2
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• pp.145-153
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• 2003

The goal of this study is to develop a biomarker used in monitoring abnormal behaviors of Japanese medaka (Oryzias latipes) as a model organism caused by hazardous chemicals. Japanese medaka was treated by copper of appropriate sublethal concentrations after starvation for 48 hr. The untreated individuals showed common behavioral characteristics (i.e. , smooth and linear movements). Locomotive activity of the fish was monitored using an image processing and automatic data acquisition system. When treated with copper (100 ppb), the fish showed shaking patterns more frequently. As the concentration of copper increased to 1,000 ppb, activity decreated, and the fish showed an erratic movement. Fish were exposed to copper at various concentrations (0,100 and 1,000 ppb) for 24 hrs, and acetylcholine esterase (AChE) activity was observed. When fish were exposed to 1,000 ppb of copper, the body AChE activities appeared to decrease but the head AChE activities showed little change. Expressions of tyrosine hydroxylase (TH) protein in the different organs from both head (brain) and body (kidney) portions affected by the copper treatment were analyzed using immunohistochemical technique compared with control. Five organs of the fish (olfactory bulb, hyothalamus, optic lobe, pons and myelencephalon regions) showed a relatively strong TH protein expression in the control experiment. A differential expression of TH, however, was observed in the treatment (100 ppb and 1,000 ppb). The treatment (1,000 ppb) significantly suppressed TH protein production in the brain regions. In kidney, however, the same treatment caused little suppression compared with the control. Copper appeared to be less effective in suppression of TH than diazinon, a known TH suppressor. It was concluded that TH could be used at a potential biomarker to monitor the acute copper toxicity in Japanese medaka.

• Journal of the Korean Association of Geographic Information Studies
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• v.22 no.3
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• pp.82-98
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• 2019

The importance of spatial information is rapidly rising. In particular, 3D spatial information construction and modeling for Real World Objects, such as smart cities and digital twins, has become an important core technology. The constructed 3D spatial information is used in various fields such as land management, landscape analysis, environment and welfare service. Three-dimensional modeling with image has the hig visibility and reality of objects by generating texturing. However, some texturing might have occlusion area inevitably generated due to physical deposits such as roadside trees, adjacent objects, vehicles, banners, etc. at the time of acquiring image Such occlusion area is a major cause of the deterioration of reality and accuracy of the constructed 3D modeling. Various studies have been conducted to solve the occlusion area. Recently the researches of deep learning algorithm have been conducted for detecting and resolving the occlusion area. For deep learning algorithm, sufficient training data is required, and the collected training data quality directly affects the performance and the result of the deep learning. Therefore, this study analyzed the ability of detecting the occlusion area of the image using various image quality to verify the performance and the result of deep learning according to the quality of the learning data. An image containing an object that causes occlusion is generated for each artificial and quantified image quality and applied to the implemented deep learning algorithm. The study found that the image quality for adjusting brightness was lower at 0.56 detection ratio for brighter images and that the image quality for pixel size and artificial noise control decreased rapidly from images adjusted from the main image to the middle level. In the F-measure performance evaluation method, the change in noise-controlled image resolution was the highest at 0.53 points. The ability to detect occlusion zones by image quality will be used as a valuable criterion for actual application of deep learning in the future. In the acquiring image, it is expected to contribute a lot to the practical application of deep learning by providing a certain level of image acquisition.

• Journal of the Korean Society for Aeronautical & Space Sciences
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• v.44 no.10
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• pp.921-932
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• 2016

In this paper, a modified FSA(Frequency Scaling Algorithm) is proposed for KOMPSAT-5 high-resolution SAR image generation. In order to enhance performance of azimuth compression, degraded in sub-aperture processing due to the imperfect geometric parameter of data acquisition, the full-aperture signal processing algorithm is designed based on the exact time-frequency analysis. In addition, an azimuth scaling function is newly devised to make the full-aperture processing algorithm suitable for KOMPSAT-5 sliding-spotlight mode. Different from the previous sub-aperture FSA schemes, the suggested technique could accommodate the merit of unified signal processing structure regardless of operational modes of KOMPSAT-5. Through the point target simulation, it is verified that the suggested algorithm provides superior performance of azimuth compression over the existing full-aperture processing methods. The experimental results using real data acquired by KOMPSAT-5 are also given to demonstrate the effectiveness of our scheme as well.

• Journal of the Korea Society of Computer and Information
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• v.19 no.12
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• pp.31-37
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• 2014

In this paper, to compensate the degraded performance in high-resolution infrared sensor due to assembling error, the influence of each component was evaluated through the sensitivity analysis of lens assembly, axis mirror, and detector and also suggested detector tilt mechanism for compensation. 3 detector tilt mechanisms were investigated. The first one is 'Shim plate' method which is applying shim on installing plane. The second one is 'Tilting screw' method that is using tilt screw for adjusting detection plane. The last one is 'Micrometer head' method that is installing micrometer on detection plane and acquiring quantitative data. Based on the investigation result, 'Tilting screw' method was applied due to ease of user control, small volume, and real-time controllability, thereby we could acquire high-resolution infrared images. The research result shows that the tilting mechanism is necessary technology for the implementation of high-resolution infrared imaging system.

• The Journal of Korean Society for Radiation Therapy
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• v.28 no.2
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• pp.149-159
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• 2016

Purpose : To evaluate the usefulness of the breathing exercise,we analyzed the change in the RPM signal and the diaphragm imagebefore 4D respiratory gated radiation therapy planning of lung cancer patients. Materials and Methods : The breathing training was enforced on 11 patients getting the 4D respiratory gated radiation therapy from April, 2016 until August. At the same time, RPM signal and diaphragm image was obtained respiration training total three steps in step 1 signal acquisition of free-breathing state, 2 steps respiratory signal acquisition through the guide of the respiratory signal, 3 steps, won the regular respiration signal to the description and repeat training. And then, acquired the minimum value, maximum value, average value, and a standard deviation of the inspiration and expiration in RPM signal and diaphragm image in each steps. Were normalized by the value of the step 1, to convert the 2,3 steps to the other distribution ratio (%), by evaluating the change in the interior of the respiratory motion of the patient, it was evaluated breathing exercise usefulness of each patient. Results : The mean value and the standard deviation of each step were obtained with the procedure 1 of the RPM signal and the diaphragm amplitude as a 100% reference. In the RPM signal, the amplitudes and standard deviations of four patients (36.4%, eleven) decreased by 18.1%, 27.6% on average in 3 steps, and 2 patients (18.2%, 11 people) had standard deviation, It decreased by an average of 36.5%. Meanwhile, the other four patients (36.4%, eleven) decreased by an average of only amplitude 13.1%. In Step 3, the amplitude of the diaphragm image decreased by 30% on average of 9 patients (81.8%, 11 people), and the average of 2 patients (18.2%, 11 people) increased by 7.3%. However, the amplitudes of RPM signals and diaphragm image in 3steps were reduced by 52.6% and 42.1% on average from all patients, respectively, compared to the 2 steps. Relationship between RPM signal and diaphragm image amplitude difference was consistent with patterns of movement 1, 2 and 3steps, respectively, except for No. 2 No. 10 patients. Conclusion : It is possible to induce an optimized respiratory cycle when respiratory training is done. By conducting respiratory training before treatment, it was possible to expect the effect of predicting the movement of the lung which could control the patient's respiration. Ultimately, it can be said that breathing exercises are useful because it is possible to minimize the systematic error of radiotherapy, expect more accurate treatment. In this study, it is limited to research analyzed based on data on respiratory training before treatment, and it will be necessary to verify with the actual CT plan and the data acquired during treatment in the future.

• Journal of the Korean Association of Geographic Information Studies
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• v.11 no.1
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• pp.80-89
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• 2008

Mapping applications using satellite imagery have been possible to quantitative analysis since SPOT satellite with stereo image was launched. Especially, high resolution satellite imagery was efficiently used in the field of digital mapping for the areas which are difficult to produce large-scale maps by aerial photogrammetry or carry out ground control point surveying due to unaccessibility. This study extracted the geospatial information out of consideration for topographic characteristic from ortho imagery of the National Geospatial-intelligence Agency(NGA) in the United States of America and analyzed the accuracy of plane coordinate for ortho imagery. For this purpose, the accuracy according to topographic character by comparison between both extraction data from ortho imagery and the digital topographic maps of 1:5000 scale which were produced by Korea National Geographic Information Institute(NGI) was evaluated. It is expected that the results of this study will be fully used as basic information for ground control point acquisition or digital mapping in unaccessible area.

• Journal of Sensor Science and Technology
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• v.7 no.2
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• pp.124-130
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• 1998

High-speed 3D vision systems are essential for autonomous robot or vehicle control applications. In our study, a stereo vision process has been developed. It consists of three steps : extraction of edges in right and left images, matching corresponding edges and calculation of the 3D map. This process is implemented in a VME 150/40 Imaging Technology vision system. It is a modular system composed by a display, an acquisition, a four Mbytes image frame memory, and three computational cards. Programmable accelerator computational modules are running at 40 MHz and are based on TMS320C31 DSP with a $64{\times}32$ bit instruction cache and two $1024{\times}32$ bit internal RAMs. Each is equipped with 512 Kbytes static RAM, 4 Mbytes image memory, 1 Mbytes flash EEPROM and a serial port. Data transfers and communications between modules are provided by three 8 bit global video bus, and three local configurable pipeline 8 bit video bus. The VME bus is dedicated to system management. Tasks between DSPs are distributed as follows: two DSPs are used to edges detection, one for the right image and the other for the left one. The last processor computes the matching process and the 3D calculation. With $512{\times}512$ pixels images, this sensor generates dense 3D maps at a rate of about 1 Hz depending of the scene complexity. Results can surely be improved by using a special suited multiprocessors cards.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.21 no.1
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• pp.130-136
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• 2017

Recently, as demand of video processor unit rapidly increases, excellent quality of the video has been required. However, generally, video data occurs the quick flame of video due to various external causes in process of acquisition, treatment, and transmission, and major cause of the quick flame of the video is known as the noise. There are various kinds of noise, which are added to the video, AWGN is a typical one. Thus, this thesis suggested algorithm that treats in three methods by scale of the edge through using edge information of local masks. In case that edge pixel is big, it applied spatial weighting according to equation of straight line about direction of edge pixel. In case that edge pixel is middle, it suggested algorithm with spatial weighting filter and average filter, and for the smooth territory, it suggested algorithm that treats with average filter.