• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2008.10a
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• pp.348-353
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• 2008

Despite the increasing popularity of wireless sensor network, indoor positioning using low power IEEE 802.15.4 compliant radio had attracted an interest of many researchers in the last decade. Old fashionable indoor location sensing information has been presented in dull and unpleasant 2D image standard. This paper focused on visualizing high precision 3 dimensional RSSI-based (received signal strength indication) spatial sensing information in an interactive virtual reality on PDA. The developed system operates by capturing and extracting signal strength information at multiple pre-defined reference nodes to provide information in the area of interest, thus updating user's location in 3D indoor virtual map. VRML (Virtual Reality Modeling Language) which specifically developed for 3D objects modeling is utilized to design 3D indoor environment.

• Korean Journal of Remote Sensing
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• v.33 no.5_3
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• pp.787-798
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• 2017

In the present study, the interior orientation parameters were computed by using various kinds of methods. Five DSMs (Digital Surface Models) in total were produced by applying interior orientation parameters to the image processing, and the accuracy was evaluated. In order to use interior orientation parameters as independent variables of DSM accuracy, flight parameters and exterior orientation parameters that can affect the accuracy of DSM were set to be the only fixed variables. From the results of the present study, the RMSE of campaign 3-2 was found to be 0.0305 m, which was the most favorable result. Thus, it is advisable to produce DSM by adjusted interior parameters after figuring out the interior orientation parameters using a camera calibration program at laboratory environment.

• Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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• v.30 no.2
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• pp.117-124
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• 2012

Due to recent urban maintenance project for the aged towns, the reconstruction of apartments into super-high-rise and high-rise apartment structures has been approved for concentrated use of land, and accordingly the infringement on sunshine for nearby residential area is rising as a social issue. Especially the educational environment conditions according to infringement on sunshine in educational facilities are posing many problems. Accordingly in this study, for such sunshine analysis of educational environment, Auto $CAD^{(R)}$ software has been used to construct the 3D model for the educational facility structures. And with the simulation technique, the windows and the schoolyard of the education facility were set to be the lighting standard surface to take measurements for the sunshine environment of the educational facilities by the minute from 8:00AM until 4:00PM for the sunshine amount by true solar time according to the movement of the sun. Also, the sunshine environment of the education facility according to the damage before/after new construction of apartments was charted, and through comparison with the video produced by sun shadow projection method, the sunshine amount of the educational environment could be verified. In future, it is expected to be efficiently used in the sunshine analysis of education environment utilizing such simulation techniques.

• Clinics in Shoulder and Elbow
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• v.8 no.2
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• pp.110-116
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• 2005

Purpose: Urgent diagnosis and treatment of the septic arthritis is required. The purpose of this study is to review to correlate preoperative MRI findings with arthroscopic findings in septic arthritis of the glenohumeral joint. Materials and Methods: Eleven patients with acute septic arthritis of the glenohumeral joint were treated with combination of arthroscopic lavage, debridement, and systemic antibiotics. The arthroscopic staging of infection was made based on the modified criteria of $G\"{a}chter$ and five major findings of MRI were marked in each stage of septic shoulder. Results: Bone and cartilage erosion was the end stage finding and two patients with all five positive findings had failed with arthroscopic treatment. Reactive bone marrow edema was evident in the greater tuberosity. Joint effusion, synovial thickening and soft tissue edema were rather non-specific finding and presented in all stages of septic shoulder. Conclusion: Diffuse marrow edema with metaphyseal cyst formation in the preoperative MRI implied advanced stage of septic arthritis, which may fail with arthroscopic debridement.

• Journal of the Institute of Convergence Signal Processing
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• v.8 no.4
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• pp.285-292
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• 2007

SoC which deploys software modules as well as hardware IPs on a single chip is a major revolution taking place in the implementation of a system design, and high-level synthesis is an important process of SoC design methodology. Recently, SPARK parallelizing high-level synthesis software tool has been developed. It takes a behavioral ANSI-C code as an input, schedules it using code motion and various code transformations, and then finally generates synthesizable RTL VHDL code. Although SPARK employs various loop transformation algorithms, the synthesis results generated by SPARK are not acceptable for basic signal and image processing algorithms with nested loop. In this paper we propose a SoC platform with an application-specific PLD targeting local operations which are feature of many loop algorithms used in signal and image processing, and demonstrate design process which maps behavioral specification with nested loops written in a high-level language (ANSI-C) onto 2D systolic array. Finally the derived systolic array is implemented on the proposed application-specific PLD of SoC platform.

• Imaging Science in Dentistry
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• v.39 no.2
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• pp.75-79
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• 2009

Purpose: To investigate the incidence and prevalence of C-shaped root canal using computed tomographic images of head and neck in Korean population. Materials and Methods : Regardless of each examination purpose, randomly selected 268 examples which have serial axial computed tomographic images with 8 normal molars in maxilla and mandible were selected and investigated. Defined C-shaped root canal and we could get 82 proper image examples in view of this definition. These were detected and investigated of incidence and prevalence of C-shaped root canal. Results: C-shaped root canals were found in 82 examples among 268 (30.6%) and 147 teeth. They were only found on molar area, and the highest incidence was 37.41% of left mandibular second molars, and the lowest was 2.04% of right maxillary second molars. On prevalence of tooth position, mandibular second molar was the highest, 65% of C-shaped root canal teeth and maxillary second molar was 6% the lowest. Conclusion: 31% of randomly selected CT images no considering check-up reason have C-shaped root canals. The C-shaped root canals of mandibular second molar are found most frequently and they are also detectable on maxilla. On Korean population, C-shaped root canals are one of conditions that have to concern with dental treatment for it appears at a high prevalence relatively. (Korean J Oral Maxillofac Radiol 2009; 39: 75-9)

• Journal of Korean Academy of Oral and Maxillofacial Radiology
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• v.15 no.1
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• pp.75-83
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• 1985

Bitewing and periapical radiographic techniques are used in clinical and epidemiological studies to assess crestal alveolar bone levels. The purpose of the present study investigated relationships between these techniques by assessing alveolar crest location at the same site. Bitewing and periapical radiographs were available from posterior quadrants of 120 subjects. The distance from cemento-enamel junction to the alveolar crest (CEJ -CR) was measured for each proximal surface from the distal of the cuspid to the distal of the second molar. Data were arranged according to the proximal surface examined, and bitewing and periapical measurements were compared using paired tests. The obtained results were as follows; 1. In maxilla, a significant t ratio with a P value of 0.05 or less was reached for 78% and in mandible reached for 39%. 2. Pearson correlations were calculated 32 surfaces (89%) had values below 0.70 and so, data obtained by these techniques can not be used interchangeably on an individual or group basis. 3. In situations where the periapical measure was greater than the bitewing, it ranged up to 20.7% greater with a mean 9.8%. Where the bitewing was greater than periapical, it ranged up to 51. 9% greater, with a mean 18.2%. 4. The percentage difference was greater in maxillary posterior areas than in mandibular molar, premolar areas. A lower prevalence of significant differences was attributed to relatively more simple root and favorable radiographic conditions in mandibular molar and premolar areas. 5. The anatomical limitations imposed on periapical radiographic technique, most often result in somewhat foreshortened radiographic images. This situation would tend to be accentuated by the anatomical restrictions of the hard palate. 6. Consequently, since the significant differences frequently exist between measurements obtained from bitewing and periapical techniques, it is important to define which technique is used.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2010.05a
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• pp.676-678
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• 2010

Conventional Augmented Reality has used data gloves or markers for smooth interaction between objects and background. This causes inconvenience of use and lower immersion. To build up immersion in Augmented Reality, additional input devices must be removed. This paper proposes a method to create virtual space coordinates for interaction without wearing additional input devices so as to improve immersion in Augmented Reality. The acquired image was projected to a two-dimensional space and vanishing lines were extracted to calculate the virtual space coordinates. Then the sizes of the inserted objects were varied in accordance with the size of the virtual coordinates area based on the image projected onto the two-dimensional coordinates. This resulted in improved immersion. This method can increase the efficiency of object creation by excluding the use of a 3D modeler for creation of three-dimensional objects.

• Journal of Navigation and Port Research
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• v.35 no.10
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• pp.811-816
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• 2011

In this paper, we analysis to consider the performance of PSPM (Phase Shift Pulse-position Modulation), the one of the low power communication technique, in near-field underwater sound channel by sea trial. PSPM is a QPSK(Quadrature Phase Shift Keying) modulation combined with PPM(Pulse Position Modulation) for low power communication in WBAN(Wireless Body Area Network). It is known that the bandwidth efficiency of PSPM is lower than conventional PSK but the power efficiency increases. In this paper, we will analyze the BER performance of PSPM using data acquired from the sea trials. The BER of QPSK was $6.04{\times}10^{-2}$, PSPM was $3.5{\times}10^{-1}$. Also, PSNR of QPSK was 9.37 dB and in case of PSPM was 9.11 dB.

• Proceedings of KOSOMES biannual meeting
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• 2008.05a
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• pp.169-171
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• 2008

The objective of this paper is to explore the short-term variability of sea surface temperature (SST) and chlorophyll a (Chl-a) derived from satellite in the upwelling region of the southeast coast of Korea in summer. We particularly emphasize the spatial variability of SST and Chl-a in the East Korean Warm Current (EKWC) during summer monsoon. Spatial distribution of SST and Chl-a in the EKWC are described using SeaWiFS and AVHRR images in August, 2007. Spatial distribution of SST and Chl-a around EKWC can be classified into four categories in the profile of SST and Chl-a images: (1) coastal cold water region, (2) cold water region of thermal front, (3) warm water region, (4) cold water of offshore region.