• Journal of Navigation and Port Research
• /
• v.38 no.2
• /
• pp.121-126
• /
• 2014

This paper suggests a new algorithm to provide low-cost GPS modules with DGPS service, which corrects the error vector in the already-calculated position by projecting range corrections to position domain using the observation matrix calculated from the satellite elevation and azimuth angle in the NMEA GPGSV data. The algorithm reduced the horizontal and vertical RMS error of U-blox LEA-5H module from 1.8m/5.8m to 1.0m/1.4m during the daytime. The algorithm has advantage in improving the performance of low-cost module to that of DGPS receiver by a software update without any correction in hardware, therefore it is expected to contribute to the vitalization of the future high-precision position service infrastructure by reducing the costumer cost and vender risk.

• Journal of the Korea Concrete Institute
• /
• v.17 no.3 s.87
• /
• pp.369-374
• /
• 2005

This study proposes a technique for the recognition of crack patterns, which includes horizontal, vertical, diagonal($-45^{\circ}$), diagonal($+45^{\circ}$), and random cracks, based on image processing technique and artificial neural network. A MATLAB code was developed for the proposed image processing algorithm and artificial neural network. Features were determined using total projection technique, and the structure(no. of layers and hidden neurons) and weight of artificial neural network were determined by learning from artificial crack images. In this process, we adopted Bayesian regularization technique as a generalization method to eliminate overfitting Problem. Numerical tests were performed on thirty-eight crack images to examine validity of the algorithm. Within the limited tests in the present study, the proposed algorithm was revealed as accurately recognizing the crack patterns when compared to those classified by a human expert.

• Journal of Korean Academy of Oral and Maxillofacial Radiology
• /
• v.21 no.1
• /
• pp.99-107
• /
• 1991

The purpose of this study was to decide the proper projection angle that could avoid the superimposition of the petrous portion of temporal bone and posterior clinoid process in cephalometric lateral and basal view of the 10 dry skulls and to analyze the reproducibility of a modified Accurad-100 head holder device from Denar Co. and a cephalostat head holder in 30 transcranial radiographs of the dry skull. The results were obtained as follows: The vertical angle was 24.5±4.1° and the horizontal angle was 3.0 ±5.7°. The distances between arbitrary 3 points which were on the TMJ area were as follows: AB 16.76±0.27㎜, BC 8.79±0.18㎜ in the transcranial radiographs using modified Accurad-100 head holder, AB 29.03±0.14㎜, AC 19.95±0.24㎜, BC 10.08±0.07㎜ in the transcranial radiographs using cephalostat.

• Atmosphere
• /
• v.27 no.2
• /
• pp.133-150
• /
• 2017

This study evaluates CMIP5 model performance on rainy season evolution in the East Asian summer monsoon. Historical (1986~2005) simulation is analyzed using ensemble mean of CMIP5 19 models. Simulated rainfall amount is underestimated than the observed and onset and termination of rainy season are earlier in the simulation. Compared with evolution timing, duration of the rainy season is uncertain with large model spread. This area-averaged analysis results mix relative differences among the models. All model show similarity in the underestimated rainfall, but there are quite large difference in dynamic and thermodynamic processes. The model difference is shown in horizontal distribution analysis. BEST and WORST group is selected based on skill score. BEST shows better performance in northward movement of the rain band, summer monsoon domain. Especially, meridional gradient of equivalent potential temperature and low-level circulation for evolving frontal system is quite well captured in BEST. According to RCP8.5, CMIP5 projects earlier onset, delayed termination and longer duration of the rainy season with increasing rainfall amount at the end of 21st century. BEST and WORST shows similar projection for the rainy season evolution timing, meanwhile there are large discrepancy in thermodynamic structure. BEST and WORST in future projection are different in moisture flux, vertical structure of equivalent potential temperature and the subsequent unstable changes in the conditional instability.

• Journal of the Institute of Electronics Engineers of Korea SC
• /
• v.47 no.1
• /
• pp.7-16
• /
• 2010

Face recognition of face images is an active subject in the area of computer pattern recognition, which has a wide range of potential. Automatic extraction of face image of the feature points is an important step during automatic face recognition. Whether correctly extract the facial feature has a direct influence to the face recognition. In this paper, a new method of facial feature extraction based on Discrete Wavelet Transform is proposed. Firstly, get the face image by using PC Camera. Secondly, decompose the face image using discrete wavelet transform. Finally, we use the horizontal direction, vertical direction projection method to extract the features of human face. According to the results of the features of human face, we can achieve face recognition. The result show that this method could extract feature points of human face quickly and accurately. This system not only can detect the face feature points with great accuracy, but also more robust than the tradition method to locate facial feature image.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
• /
• 2011.10a
• /
• pp.907-910
• /
• 2011

This paper proposes a character segmentation algorithm of steel plate images composed of adaptive binarization by the SCW (Sliding Concentric Windows) technique, the object labelling by CCA (Connected Component Analysis), and 2D projection method. The SCW technique carries out the grayscale-to-binary image conversion in consideration of local characteristics of images. The character decision algorithm followed by the labelling technique by CCA (Connected Component Analysis) determines the character area effectively reducing the noise effect. The 2D projection with horizontal and vertical directions produces a tight bounding box for a character based on the cross points. Experimental results indicate that the proposed algorithm segments the characters in steel plate images effectively. The proposed algorithm can be applied to the devices with limited resources due to its excellent performance and low complexity.

• Journal of Korea Multimedia Society
• /
• v.15 no.6
• /
• pp.737-747
• /
• 2012

Recently, in order to support automatic meter reading for conventional metering devices, an image processing-based approach of recognizing the number meter data in the captured meter images has attracted many researchers' interests. Numerical character segmentation is a very critical process for successful recognition. In this paper, we propose an efficient numeric character segmentation method which can segment numeric characters well for any metering device types under diverse illumination environments. The proposed method consists of two consecutive stages; detection of number area containing all numbers as a tight ROI(Region of Interest) and segmentation of numerical characters in the ROI. Detection of tight ROI is achieved in two steps: extraction of rough ROI by utilizing horizontal line segments after illumination enhancement preprocessing, and making the rough ROI more tight through clipping utilizing vertical and horizontal projection about binarized ROI. Numerical character segmentation in the detected ROI is stably achieved in two processes of 'vertical segmentation of each number region' and 'number segmentation in the each vertical segmented number region'. Through the experiments about a homegrown meter image database containing various meter type images of low contrast, low intensity, shadow, and saturation, it is shown that the proposed numeric character segmentation method performs effectively well for any metering device types under diverse illumination environments.

• Journal of Digital Contents Society
• /
• v.8 no.3
• /
• pp.329-339
• /
• 2007

In this paper we present a facial region detection algorithm for real-time image with complex background and various illumination using spatial and temporal methods. For Detecting Human region It used summation of Edge-Difference Image between continuous image sequences. Then, Detected facial candidate region is vertically divided two objected. Non facial region is reduced using Analysis of Major Color Component. Non facial region has not available Major Color Component. And then, Background is reduced using boundary information. Finally, The Facial region is detected through horizontal, vertical projection of Images. The experiments show that the proposed algorithm can detect robustly facial region with complex background various illumination images.

• Journal of Oral Medicine and Pain
• /
• v.23 no.1
• /
• pp.45-55
• /
• 1998

The author assessed the sagittal relationships between glenoid fossa of the temporal bone and mandibular condyle from lateral transcranial views of 74 TMJ with disc displacement and 16 TMJ with normal disc-condyle complex by the magnetic resonance image findings. All the subjects were female and also in their 3rd decades. The disc displacement group was subdivided into anterior disc displacement with reduction (ADWR) group and anterior disc displacement without reduction (ADWOR) group. The anterior, superior, and posterior joint spaces as well as anterior/posterior (A/P) ratio of the space at the closed jaw position and vertical and horizontal components of the condyle position relative to the articular eminence at the open jaw position were measured from all the subjects and the data were compared among groups. The result were as follows : 1. The mean posterior joint space of ADWR group was smaller than ADWOR group, but there were no significant differences in anterior and superior joint spaces between two groups. 2. There showed a tendency of higher A/P ratio in ADWR group which meant the condyle of ADWR was likely to take posteriorly displaced position. 3. There were higher proportion of neutral condylar position in glenoid fossa in normal group, but higher proportion of posterior condylar position in ADWR group. 4. There were no significant differences in the degree of condyle-fossa concentricity among groups.

• Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
• /
• v.14 no.2
• /
• pp.241-247
• /
• 1996

The most important factor in highway design is to match highway alignment with topography so that the driver can drive the vehicle safely and comfortably. Highway alignment design is completed with combination of horizontal alignment and vertical alignment that is harmony with topography at the last step. In highway alignment design, the use of continuous perspective can meet vehicle's physical requirements, which is useful to keep driver's psychological and physiological balance. The main purpose of this study is to develop a computer pro-gram which is applicable to highway alignment design through study of how to make and analyze perspective by means of computer.