• Korean Journal of Remote Sensing
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• v.37 no.5_1
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• pp.1095-1109
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• 2021

The technology used to recognize the location and surroundings of autonomous vehicles is called SLAM. SLAM standsfor Simultaneously Localization and Mapping and hasrecently been actively utilized in research on autonomous vehicles,starting with robotic research. Expensive GPS, INS, LiDAR, RADAR, and Wheel Odometry allow precise magnetic positioning and mapping in centimeters. However, if it can secure similar accuracy as using cheaper Cameras and GPS data, it will contribute to advancing the era of autonomous driving. In this paper, we present a method for converging monocular camera with RTK-enabled GPS data to perform RMSE 33.7 cm localization and mapping on the urban road.

• Proceedings of the Korean Institute of IIIuminating and Electrical Installation Engineers Conference
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• 2006.05a
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• pp.125-130
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• 2006

In this study, tests of brain waves were carried out to investigate the driver's physiological characteristics by the change of the headlight. The participants were 20 men in their 20s and twenty-three different conditions in combinations of waveform of light, voltage, and alteration time were used. The measurement of the brain waves was performed by internationally standardized 10-20 method using LXE3232-RF. The results were analyzed by Power Spectrum Analysis using alpha-, and beta-wave and by the analysis of different brain domains using Brain wave Map. The results were as follows. 1. From the results of the Brain wave Map analysis, it was suggested that A waveform increases mental stress and B waveform affects mental and visual stress. The longer the stimulation time, the more stress level was detected. 2 The voltage alteration time of B waveform should be kept less than 1500msec, and the voltage should not fall below 11.5V.

• Journal of Information Processing Systems
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• v.15 no.1
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• pp.169-180
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• 2019

Transmitting visual information over a broadcasting network is not only prone to a copyright violation but also is a forgery. Authenticating such information and protecting its authorship rights call for more advanced data encoding. To this end, electronic watermarking is often adopted to embed inscriptive signature in imaging data. Most existing watermarking methods while focusing on robustness against degradation remain lacking of measurement against security loophole in which the encrypting scheme once discovered may be recreated by an unauthorized party. This could reveal the underlying signature which may potentially be replaced or forged. This paper therefore proposes a novel digital watermarking scheme in temporal-frequency domain. Unlike other typical wavelet based watermarking, the proposed scheme employed the Lorenz chaotic map to specify embedding positions. Effectively making this is not only a formidable method to decrypt but also a stronger will against deterministic attacks. Simulation report herein highlights its strength to withstand spatial and frequent adulterations, e.g., lossy compression, filtering, zooming and noise.

• Korean Journal of Remote Sensing
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• v.39 no.1
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• pp.1-21
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• 2023

In this technically advanced era, we are surrounded by smartphones, computers, and cameras, which help us to store visual information in 2D image planes. However, such images lack 3D spatial information about the scene, which is very useful for scientists, surveyors, engineers, and even robots. To tackle such problems, depth maps are generated for respective image planes. Depth maps or depth images are single image metric which carries the information in three-dimensional axes, i.e., xyz coordinates, where z is the object's distance from camera axes. For many applications, including augmented reality, object tracking, segmentation, scene reconstruction, distance measurement, autonomous navigation, and autonomous driving, depth estimation is a fundamental task. Much of the work has been done to calculate depth maps. We reviewed the status of depth map estimation using different techniques from several papers, study areas, and models applied over the last 20 years. We surveyed different depth-mapping techniques based on traditional ways and newly developed deep-learning methods. The primary purpose of this study is to present a detailed review of the state-of-the-art traditional depth mapping techniques and recent deep learning methodologies. This study encompasses the critical points of each method from different perspectives, like datasets, procedures performed, types of algorithms, loss functions, and well-known evaluation metrics. Similarly, this paper also discusses the subdomains in each method, like supervised, unsupervised, and semi-supervised methods. We also elaborate on the challenges of different methods. At the conclusion of this study, we discussed new ideas for future research and studies in depth map research.

• Science of Emotion and Sensibility
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• v.6 no.1
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• pp.1-10
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• 2003

Information gathered through experience transforms into knowledge and such knowledge becomes a foundation for intuitive decisions. Based on such background, the following study investigates intuitive decision making on basic elements needed for design concepts and visual conceptualizations. The study consist two phases. first, 12 structural elements of a digital camera and relation between each elements were arranged intuitively on a board. Next, sketches were generated with relationship of structural elements in mind. As a result of the study, concept with intuitive decisions effect structural thinking, various developments, specific operation methods , and sketch expressions. However, study also revealed that the freedom of human emotions don't accord with the qualification map.

• The Journal of the Institute of Internet, Broadcasting and Communication
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• v.8 no.1
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• pp.47-52
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• 2008

The visual implementation of 3-dimensional national environment is focused by the requirement and importance in the fields such as, urban planing, telecommunication facility deployment plan, railway construction, construction engineering, spatial city development, safety and disaster prevention engineering. The currently used DEM system based on the 2-D digital maps and contour lines has limitation in implementation in reproducing the 3-D spatial city. Currently, the LiDAR data which combines the laser and GPS skill has been introduced to obtain high resolution accuracy in the altitude measurement in the advanced country. In this paper, we first introduce the LiDAR based researches in advanced foreign countries, then we propose the data generation scheme and an solution algorithm for the optimal management of our 3-D spatial u-City construction. For this purpose, LiDAR based height data transformed to DEM, and the realtime unification of the vector via digital image mapping and raster via exactness evaluation is transformed to make it possible to trace the model of generated 3-dimensional model with long distance for 3D u-city model generation.

• Journal of the Korea Society of Computer and Information
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• v.21 no.8
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• pp.57-64
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• 2016

Initial prevention activities and rapid propagation conditions is the most important to prevent diffusion of water pollution. If water pollutants flow into streams river or main stresm located in environmental conservation area or water intake facilities, we must predict immediately arrival time and the diffusion concentration to the proactive. National Institute of Environmental Research developed water pollution incident response prediction system linking dam and movable weir. the system is mathematical model which is updated daily. Therefore it can quickly predict the arrival time and the diffusion concentration when there are accident of oil spills and hazardous chemicals. Also we equipped with mathematical model and toxicity model of EFDC(Environmental Fluid Dynamics Code) to calculate the arrival time and the diffusion concentration. However these systems offer the services of an offline manner than real-time control services. we have ensured the reliability of data collection and have developed a real-time water quality measurement data transmission device by using the data linkage utilizing a mode bus communication and a commercial SCADA system, in particular, we implemented to be able to do real-time water quality prediction through information infrastructure of the water quality integrated management business created by utilizing the construction of the real-time prediction system that utilizes the data collected, the Open map, the visual representation using charts API and development of integrated management system development based on web maps.

• Journal of Korean Academy of Fundamentals of Nursing
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• v.7 no.2
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• pp.256-270
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• 2000

Invasive hemodynamic monitoring has become a valuable assessment parameters in critical care nursing in patients undergoing open heart surgery patients. During cardiac surgery, the Swan Ganz catheter is placed in the pulmonary artery. Critical care nurses routinely obtain cardiac output, cardiac index, and pulmonary arterial pressure in these patients. Traditionally, patients are positioned flat and supine for cardiac output measurement. Numerous studies have dealt with the effects of changing position on the hemodynamic variables. However, there are a few studies dealing with patients who undergo cardiac surgery in Korea. Thus, the purpose of this study was to determine the effects of changing position on cardiac output, PAP, CVP, BP, HR and discomfort in patients after cardiac surgery. A sample of 21 adults who had CABG and/or valve replacement with Swan Ganz catheters in place was studied. The data were collected in the cardiac ICU of a university hospital in Seoul during the period from July 28, 1999 to August 30. 1999. In this study, the independent variable is patient position in the supine, 30 degree, and 45 degree angles. Dependent variables are C.O., C.I., CVP, PAP, MAP, HR and patients' perceived discomforts. Subject discomfort was measured subjectively by visual analogue scale. Other hemodynamic data where collected by the thermodilution method and by direct measurement. The data were analyzed by percentile, t-test, ANOVA, Linear regression analysis using SPSS-/WIN program. The results are as follows : 1) Changes in cardiac output were absent in different angle positions, 0, 30. 45 degrees(F=.070, P=.932). Changes in cardiac index were absent in different angle positions, 0. 30, 45 degrees(P>.05). 2) Changes in central venous pressure were absent in different angle positions, 0, 30, 45 degree(P>.05). 3) PAP had no change in different angle 0, 30, 45 degree positions; systolic PAP(P>.05), diastolic PAP(P>.05). 4) Changes in systolic blood pressure were absent in different angle positions, 0, 30, 45 degree(P>.05). 5) Changes in heart rates were absent in different angle positions, 0, 30, 45 degree(P>.05). 6) Patients' perceived discomfort was absent in different angle positions, 0, 30, 45 degree(p<.05). In conclusion, critical care nurses can measure C.O., C.I., PAP, BP, & CVP in cardiac surgery patients at 30 degree or 45 degree positions. This can improve the patients' comfort.

• Journal of Biomedical Engineering Research
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• v.27 no.5
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• pp.203-209
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• 2006

The aim of this study is to investigate the feasibility of ex vivo MR diffusion tensor imaging technique in order to observe the diffusion-contrast characteristics of human gastric tissues. On normal and pathologic gastric tissues, which have been fixed in a polycarbonate plastic tube filled with 10% formalin solution, laboratory made 3D diffusion tensor Turbo FLASH pulse sequence was used to obtain high resolution MR images with voxel size of $0.5{\times}0.5{\times}0.5mm^3\;using\;64{\times}32{\times}32mm^3$ field of view in conjunction with an acquisition matrix of $128{\times}64{\times}64$. Diffusion weighted- gradient pulses were employed with b values of 0 and $600s/mm^2$ in 6 orientations. The sequence was implemented on a clinical 3.0-T MRI scanner(Siemens, Erlangen, Germany) with a home-made quadrature-typed birdcage Tx/Rx rf coil for small specimen. Diffusion tensor values in each pixel were calculated using linear algebra and singular value decomposition(SVD) algorithm. Apparent diffusion coefficient(ADC) and fractional anisotropy(FA) map were also obtained from diffusion tensor data to compare pixel intensities between normal and abnormal gastric tissues. The processing software was developed by authors using Visual C++(Microsoft, WA, U.S.A.) and mathematical/statistical library of GNUwin32(Free Software Foundation). This study shows that 3D diffusion tensor Turbo FLASH sequence is useful to resolve fine micro-structures of gastric tissue and both ADC and FA values in normal gastric tissue are higher than those in abnormal tissue. Authors expect that this study also represents another possibility of gastric carcinoma detection by visualizing diffusion characteristics of proton spins in the gastric tissues.

• Korean Journal of Remote Sensing
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• v.34 no.3
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• pp.439-450
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• 2018

The lineament is a linear or curved terrain element to discriminate adjacent geological structures in each other. It has been widely used for analysis of geology, mineral exploration, natural disasters, and earthquake, etc. In the past, the lineament has been extracted using cartographic map or field survey. However, it is possible to extract more efficiently the lineament for a very wide area thanks to development of remote sensing technique. Remotely sensed observation by aircraft, satellite, or digital elevation model (DEM) has been used for visual recognition for manual lineament extraction. Automatic approaches using computer science have been proposed to extract lineament more objectively. In this study, we evaluate the characteristics of lineament which is automatically extracted with respect to difference of spatial resolution of DEM. We utilized two types of DEM: one is Shuttle Radar Topography Mission (SRTM) with spatial resolution of about 90 m (3 arc sec), and the other is the latest world DEM of TerraSAR-X add-on for Global DEM with 12 m spatial resolution. In addition, a global DEM was resampled to produce a DEM with a spatial resolution of 30 m (1 arc sec). The shaded relief map was constructed considering various sun elevation and solar azimuth angle. In order to extract lineament automatically, we used the LINE module in PCI Geomatica software. We found that predominant direction of the extracted lineament is about $N15-25^{\circ}E$ (NNE), regardless of spatial resolution of DEM. However, more fine and detailed lineament were extracted using higher spatial resolution of DEM. The result shows that the lineament density is proportional to the spatial resolution of DEM. Thus, the DEM with appropriate spatial resolution should be selected according to the purpose of the study.