• Journal of Convergence for Information Technology
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• v.10 no.6
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• pp.28-34
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• 2020

A structure in which GaAs and AlGaAs epilayers are formed with a metal organic chemical vapor deposition equipment on a GaAs wafer similar to the structure of making a vertical cavity surface emitting laser is used. Photonic Quantum Ring (PQR) devices that are naturally generated by 3D resonance are manufactured by chemically assisted ion beam etching technology, which is a dry etching method. A new technology that can be fabricated has been studied, and as a result, the possibility of wet etching of a solution containing phosphoric acid, hydrogen peroxide and methanol was investigated, and the device fabrication by applying this method are also discussed. In addition, the spectrum of the fabricated optical device was measured, and the results were theoretically analyzed and compared with the wavelength value obtained by the measurement. It is expected that the PQR device will be able to model cells in a three-dimensional shape or be applied to the display field.

• Journal of the Korean Society for Precision Engineering
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• v.19 no.3
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• pp.66-72
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• 2002

Electronic Speckle Pattern Interferometry (ESPI) has been recently developed and widely used because it has advantage to be able to measure surface deformations of engineering components and materials in industrial areas with non-contact. The speckle patterns to be formed with interference and scattering phenomena can measure not only out-of-plane but also in-plane deformations, together with the use of digital image equipment to process the informations included in the speckle patterns and to display consequent interferogram on a computer monitor. In this study, the experimental results of a canti-levered plate using ESPI were compared with those obtained from the simple beam theory. The ESPI results of the canti-levered plate analyzed by 4-step phase shifting method are close to the theoretical expectation. Also, out-of-plane displacements of a spot welded cacti-levered plate were measured by ESPI with 4-step phase shifting technique. The phase map of the spot welded cacti-levered plate is quite different from that of the canti-levered plate without spot welding.

• Journal of the Korean Institute of Telematics and Electronics C
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• v.35C no.11
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• pp.31-38
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• 1998

This paper deals with CBS(Cycle Base Simulator) design of a 32 bit floating point DSP(Digital Signal Processor). The CBS has been developed for TMS320C30 compatible DSP and will be used to confirm the architecture, functions of sub-blocks, and control signals of the chip before the detailed logic design starts with VHDL. The outputs from CBS are used as important references at gate level design step because they give us control signals, output values of important blocks, values from internal buses and registers at each pipeline step, which are not available from the commercial simulator of DSP. In addition to core functions, it has various interfaces for efficient execution and convenient result display, CBS is verified through comparison with results from the commercial simulator for many application algorithms and its simulation speed is as fast as several tenth of that of logic simulation with VHDL. CBS in this work is for a specific DSP, but the concept may be applicable to other VLSI design.

• Journal of the Institute of Electronics Engineers of Korea SC
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• v.40 no.6
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• pp.39-47
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• 2003

This paper proposes the new narrow erase method to erase wall charges formed in an AC plasma display panel (PDP) cell. In the Proposed method, sustain switching timing is adjusted for inducing a weak discharge. Then, after the narrow erase, tile voltage of the X electrode is set to differ from that of the Y electrode. For the proposed method, the measured maximum address voltage margin was 38.3V at Y_Reset voltage of 100V and sustain voltage of 180∼185V. However, for the prior method, in which the X and Y electrodes we set to be of equal voltage after the narrow erase, the measured maximum address voltage margin was 31.3V at Y_Reset voltage of 150V and sustain voltage of 180V. This result shows that the measured maximum voltage margin for the proposed method is greater than that for the prior method by ∼7V(22%).

• Journal of the Institute of Electronics Engineers of Korea SC
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• v.43 no.6 s.312
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• pp.68-75
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• 2006

During cancer therapy by using high energy radiation, it is possible to improve the radiation therapy efficiency by performing a precise radiation therapy after verification of generated setup errors. In this paper, the video based electronic portal imaging device (EPID) which could display the portal image with near real time was developed to verify treatment position errors in radiation therapy instead of an analog typed portal film. This EPID system for applying QA tool of radiation therapy machine was consisted of a metal/fluorescent screen, $45^{\circ}$mirror, camera and image grabber. Radiation field verification has been performed to check quality assurance of the treatment machine itself by using this EPID system. The radiation field error was easily observed by edge detection of irradiated field size on EPID image when $0.6^{\circ}$ shift of collimator angle was generated. So, this implemented EPID system could be used as a radiation QA tool.

• Journal of the Institute of Electronics Engineers of Korea SP
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• v.47 no.2
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• pp.33-44
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• 2010

This paper propose the structure of real-time face detection hardware architecture for robot vision processing applications. The proposed architecture is robust against illumination changes and operates at no less than 60 frames per second. It uses Modified Census Transform to obtain face characteristics robust against illumination changes. And the AdaBoost algorithm is adopted to learn and generate the characteristics of the face data, and finally detected the face using this data. This paper describes the face detection hardware structure composed of Memory Interface, Image Scaler, MCT Generator, Candidate Detector, Confidence Comparator, Position Resizer, Data Grouper, and Detected Result Display, and verification Result of Hardware Implementation with using Virtex5 LX330 FPGA of Xilinx. Verification result with using the images from a camera showed that maximum 32 faces per one frame can be detected at the speed of maximum 149 frame per second.

• Aerospace Engineering and Technology
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• v.11 no.1
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• pp.42-48
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• 2012

The telemetry data received from satellite in real-time are used to monitor LEO satellite during the AIT (Assembly, Integration & Test) phase and the mission operation phase after launch. However, it is impossible to check all the incoming telemetry data from satellite in real time in order to detect abnormality of satellite quickly. Especially, the contact time of LEO satellite is limited because of its orbital characteristics. So the anomaly state of the LEO satellite should be detected and resolved during the contact time. Therefore, all incoming spacecraft telemetry data must be selected and manipulated in MIMIC. It is used in order to display summarized information about spacecraft in a visualized way that is quickly and easily understood. That is, it provides essential function to monitor a satellite both in orbit and during testing. In this paper, the design and development of MIMIC currently used in KOMPSAT, a LEO Earth observation satellite is described in detail. In future work, we plan to enhance MIMIC in order to improve user-friendliness and efficiency.

• Asian Pacific Journal of Cancer Prevention
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• v.16 no.14
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• pp.5903-5906
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• 2015

Background: Cholangiocarcinoma (CCA) is a serious public health problem in the Northeast of Thailand. CCA is considered to be an incurable and rapidly lethal disease. Knowledge of the distribution of CCA patients is necessary for management strategies. Objectives: This study aimed to utilize the Geographic Information System and Google $Earth^{TM}$ for distribution mapping of cholangiocarcinoma in Satuek District, Buriram, Thailand, during a 5-year period (2008-2012). Materials and Methods: In this retrospective study data were collected and reviewed from the OPD cards, definitive cases of CCA were patients who were treated in Satuek hospital and were diagnosed with CCA or ICD-10 code C22.1. CCA cases were used to analyze and calculate with ArcGIS 9.2, all of data were imported into Google Earth using the online web page www.earthpoint.us. Data were displayed at village points. Results: A total of 53 cases were diagnosed and identified as CCA. The incidence was 53.57 per 100,000 population (65.5 for males and 30.8 for females) and the majority of CCA cases were in stages IV and IIA. The average age was 67 years old. The highest attack rate was observed in Thung Wang sub-district (161.4 per 100,000 population). The map display at village points for CCA patients based on Google Earth gave a clear visual deistribution. Conclusions: CCA is still a major problem in Satuek district, Buriram province of Thailand. The Google Earth production process is very simple and easy to learn. It is suitable for the use in further development of CCA management strategies.

• Fashion & Textile Research Journal
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• v.17 no.1
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• pp.74-81
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• 2015

This study explored the degree of cognition, purchasing experience and attitudes towards SPA brand attributes. This study examined the differences in variables and demographic characteristics against appearance interest groups. A questionnaire survey collected data from November $1^{st}$ and $15^{th}$ 2012. The convenience sample was drawn from females between the ages of 20 and 39 who lived in the Daegu and Gyeongbuk regions of South Korea. A total of 255 responses were complete and usable questionnaires. Data were tested through factor analysis, t-test, and ${\chi}^2$ test using SPSS 21.0. The results show that there were significant group differences in the cognition and purchasing experience of SPA brands and the attitudes towards SPA brand attributes. The high appearance interest group was more aware of SPA brands and evaluated SPA brand attributes more positively and bought more SPA brand products than the low appearance interest group. The high appearance interest group showed that domestic brands were excellent in low price among brand attributes but foreign brands were relatively excellent in various design and store display. There was a significant difference in educational level between appearance interest groups; however, there were no significant differences in age, marital status, and income level group. This study contributes to basic information for the SPA brand buying behavior research field and apparel industry marketing strategy by analyzing the relationship among appearance interest, cognition, SPA brand purchasing experience and SPA brand attribute attitudes.

• Journal of Advanced Navigation Technology
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• v.18 no.6
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• pp.533-540
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• 2014

We propose an age estimation-based smart digital signage for the next-generation airport service. The proposed system can recognize the face of the customer so that it can display the selective information. Using a webcam, the system captures the face of the customer and estimates the age of the customer by calculating the wrinkle density of the face and applying bayesian classifier. The developed age estimation method is tested with a face database for the performance evaluation. We expect the new digital signage may improve the satisfaction of customers of the airport business.