• The Journal of Korean Society for Radiation Therapy
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• v.16 no.2
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• pp.33-41
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• 2004

Purpose : Film has been the primary tool in coincidence testing between the light field and the radiation field, which constitutes the quality assurance list of a linear accelerator. But there is a great chance of errors being different among the observer when using film. Thus this study set out to use the BIS(Beam Image System) in addition to film in comparing and evaluating coincidence results between the two fields and in searching for the improvement measures. Materials & Methods : Photon beam of 6 and 15MV was exposed to film and the BIS using a linear accelerator. The light and radiation fields were each $50{\times}50,\;100{\times}100,\;and\;200{\times}200mm^2$. The gantry angle was $0^{\circ}$ when using film and $0^{\circ}\;and\;270^{\circ}$ when using the BIS. The devices adopted to test coincidence between the two fields were a ruler and film scanner when using film. With the BIS, the width of the scanned light and radiation fields was measured for errors with setting the X and Y axis. Results : The visual measurements of the observer with film resulted that the radiation field was bigger than the light field and that their maximum error was 1.9mm. The results were the same with the measurements using the film scanner except for the average error, which was less than 1.9mm. On the contrary, the measurements using the BIS showed that the light field was bigger than the radiation field at the gantry angle of $0^{\circ}\;and\;270^{\circ}$. The maximum error was 0.96mm, and the error range was $<{\pm}2mm$ both in the X and Y axis. The average error of ${\Delta}X$, Y was the smallest in the order of the visual film measurements, film scanner measurements, and BIS measurements Conclusion . This requires a careful measurement for accurate quality assurance since errors are much different according to each observer that tests coincidence between visual fields with film. And an observer needs to use another image device or develop a measuring device of his own if it seems necessary for accurate measurements.

• Journal of Korea Society of Digital Industry and Information Management
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• v.10 no.2
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• pp.13-20
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• 2014

In this paper, we implemented the object scanning with nxtOSEK which is an open source platform. nxtOSEK consists of device driver of leJOS NXJ C/Assembly source code, TOPPERS/ATK(Automotive real time Kernel) and TOPPERS/JSP Real-Time Operating System source code that includes ARM7 specific porting part, and glue code make them work together. nxtOSEK can provide ANSI C by using GCC tool chain and C API and apply for real-time multi tasking features. We experimented the 3D scanning with ultra sonic and laser sensor which are made directly by laser module diode and experimented the measurement of scanning the object by knowing x, y, and z coordinates for every points that it scans. In this paper, the laser module is the dimension of $6{\times}10[mm]$ requiring 5volts/5[mW], and used the laser light of wavelength in the 650[nm] range. For detecting the object, we used the beacon detection algorithm and as the laser light swept the objects, the photodiode monitored the ambient light at interval of 10[ms] which is called a real time. We communicated the 3D scanning platform via bluetooth protocol with host platform and the results are displayed via DPlot graphic tool. And therefore we enhanced the functionality of the 3D scanner for identifying the image scanning with laser sensor modules compared to ultra sonic sensor.

• The Transactions of the Korean Institute of Electrical Engineers C
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• v.54 no.8
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• pp.378-383
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• 2005

We report the development of miniature fluorescence detection systems that employ miniature prism, mirrors and low coat CCD camera to detect the fluorescence emitted from 40 fluorescently-labeled protein patterns without scanner. This kind of miniature fluorescence detection system can be used in point of care. We introduce two systems, one uses prism+mirror block and the other uses prism and two mirrors. A large NA microscope eyepiece and low cost CCD camera are used. We fabricated protein chip containing multi-pattern BSA labeled with Cy5, using MEMS technology and modified the surface chemically to clean and to immobilize proteins. The measurements show that the combination of prism and mirrors can homogenize elliptical excitation light over the sample with higher optical efficiency, and increase the separation between excitation and fluorescence light at the CCD to give higher signal intensity and higher signal to noise ratio. The measurements also show that protein concentrations ranging from 10 ng/ml to 1000 ng/ml can be assayed with very small error. We believe that the proposed fluorescence detection system can be refined to build a commercially valuable hand-held or miniature detection device.

• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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• v.18 no.4
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• pp.34-40
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• 2004

In this paper, we have studied the OCT(Optical Coherence Tomography) system which has been advantages of high resolution, 2-D cross-sectional images, low cost and small size configuration. The characteristics of light source determine the resolution and coherence length. The light source has a commercial SLD with a central wavelength of 1,285 ill11, 35.3 nm(FWHM). The optical delay line is necessary to make equal with the optical path length to scattered light or reflected light from a sample. In order to make equal the optical path length, the stage that is attached to a reference mirror is controled by a step motor. And the interferometer is configured with the Michelson interferometer by using a single mode fiber, and the scanner can be focused on the sample by using a reference ann Also, the 2-dimension cross-sectional images were measured with scanning the transverse direction of the sample by using a step motor. After detecting the internal signal of lateral direction, a scanner is moved to obtain the cross-sectional image of 2-dimension by using step motor. A photodiode, which has high detection sensitivity and excellent noise characteristics has been used. The detected small signal has a noise and interference. After filtering and amplifying the signal, the output signal is demodulated the waveform And then, a cross-sectional image is seen through converting this signal into a digitalized signal by using an AID converter. The resolution of the sample is about 30${\mu}{\textrm}{m}$, which corresponds to the theoretical resolution. Also, the cross-sectional images of onion cells were measured in real time scheme.

• International journal of advanced smart convergence
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• v.6 no.4
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• pp.88-95
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• 2017

The conventional scan methods are based on a laser scanner and a depth camera, which requires high cost and complicated post-processing. Whereas in photometric scanning method, the 3D modeling data is acquired through multi-view images. This is advantageous compared to the other methods. The quality of a photometric 3D model depends on the environmental conditions or the object characteristics, but the quality is lower as compared to other methods. Therefore, various methods for improving the quality of photometric scanning are being studied. In this paper, we aim to investigate the effect of illumination conditions on the quality of photometric scanning data. To do this, 'Moai' statue is 3D printed with a size of $600(H){\times}1,000(V){\times}600(D)$. The printed object is photographed under the hard light and soft light environments. We obtained the modeling data by photometric scanning method and compared it with the ground truth of 'Moai'. The 'Point-to-Point' method used to analyseanalyze the modeling data using open source tool 'CloudCompare'. As a result of comparison, it is confirmed that the standard deviation value of the 3D model generated under the soft light is 0.090686 and the standard deviation value of the 3D model generated under the hard light is 0.039954. This proves that the higher quality 3D modeling data can be obtained in a hard light environment. The results of this paper are expected to be applied for the acquisition of high-quality data.

• Journal of Technologic Dentistry
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• v.42 no.4
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• pp.334-340
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• 2020

Purpose: This study aimed to compare three-dimensional adaptation with the rinsing time of the temporary crown produced using the digital light processing method. Methods: The maxillary right first molar abutment was scanned with a dental scanner. A temporary crown was designed with the scanned abutment. The designed crown was made of 10 temporary crowns using a digital light processing printer. The crowns were divided into the 5-minute and 10-minute rinsing groups; 5 temporary crown washes were performed for each group. In order to obtain the internal data, each group was scanned for a temporary crown. The three-dimensional fit was measured by superimposing the scanned internal surface data and the abutment data. The average comparison of three-dimensional adaptation was analyzed using the Mann-Whitney U test. Results: The 5-minute rinsing group showed a significantly higher adaptation of 71.42±3.08 ㎛ as compared to the 10-minute rinsing group (67.52±0.92 ㎛) (p<0.05). Conclusion: When making a temporary crown with a digital light processing method, a rinsing time of 10 minutes is appropriate.

• International Journal of Internet, Broadcasting and Communication
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• v.7 no.1
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• pp.15-19
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• 2015

The depth information of an image is used in a variety of applications including 2D/3D conversion, multi-view extraction, modeling, depth keying, etc. There are various methods to acquire depth information, such as the method to use a stereo camera, the method to use the depth camera of flight time (TOF) method, the method to use 3D modeling software, the method to use 3D scanner and the method to use a structured light just like Microsoft's Kinect. In particular, the depth camera of TOF method measures the distance using infrared light, whereas TOF sensor depends on the sensitivity of optical light of an image sensor (CCD/CMOS). Thus, it is mandatory for the existing image sensors to get an infrared light image by bundling several pixels; these requirements generate a phenomenon to reduce the resolution of an image. This thesis proposed a measure to acquire a high-resolution image through gradual area movement while acquiring a low-resolution image through pixel bundling method. From this measure, one can obtain an effect of acquiring image information in which illumination intensity (lux) and resolution were improved without increasing the performance of an image sensor since the image resolution is not improved as resolving a low-illumination intensity (lux) in accordance with the gradual pixel bundling algorithm.

• Journal of the Korean BIBLIA Society for library and Information Science
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• v.4 no.1
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• pp.85-102
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• 1980

Accepting the necessity for maintaining the objectives of the existing circulation system, the computer-based system could be designed by the system analyst and librarians to gain a variety of improvements in the maintenance, accessibility of circulation records and more meaningful statistical records. If the terminal can be operated on-line, then this circulation data is transmitted directly to the computer, where it may update to the circulation file immediately or alternatively be kept in direct access file for updating in batch mode. on-line system in the circulation operations is "data-collection system" and "Bar-coded label system" Bar-coded label system is simple, quick, and error-free input of data. Attached to CRT terminal is a "light pen" which is hand held and will read a bar-coded label as the pen is passed over the labels (one affixed to the book itself, other carried on the borrower cards). Instantaneously the data concerning transaction is stored in the central mini-computer. It is useful, economical for us to co-operate many libraries in Korea and design borrower's ID code, book no., classification code in the Bar-coded label system by the members of the computer center and the library staff at every stage. As for book loan, the borrowers ID code, book number and classification code are scanned by the bar-code scanner or light pen and the computer decides whether to loan and store the data. The visual display unit shows the present status of a borrowers borrowing and decides whether borrower can borrow.

• Proceedings of the KSME Conference
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• 2003.04a
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• pp.911-916
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• 2003

Microactuator is frequently used in some optical or electrical applications such as light modulators and spatial scanner devices. When microactuator is implemented, it should be operated at accurate positions proportional to input voltage. Therefore in order to obtain rapid responses and reduced errors, a position control technique is used. In the paper, design procedure for the mems actuator and a typical PID controller is adapted to improve performance of microactuator as well. Also electrostatic force for the torsional microactuator is calculated via well-known Hornbeck's method.

• Proceedings of the KSMRM Conference
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• 2003.10a
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• pp.31-31
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• 2003

목적： 통증에 대한 fMRI 연구에 있어서 differential-regression-analysis (DRA) 기법을 사용하여 대뇌 피질에서 통증 처리에 관련된 영역의 순시적인 변화를 관찰하였다. 대상 및 방법： 우선 통증과 일반적인 감각자극과의 생리학적 차이를 밝히기 위해 운동 (finger tapping) 및 시각 (flickering light) 자극 실험이 선행되었다. 통증 유발을 위해서는 50C에서 52C의 뜨거운 물을 이용한 온도자극이 왼손의 검지와 중지에 30초 동안 가해졌다. fMRI 실험은 Marconi (Philips) 1.5 T scanner를 이용하여 gradient echo EPI sequence(TR / TE / FA = 3 sec / 35 msec / 90)로 수행되었다. 감각자극과 통증자극에 대한 반응의 동적인 변화를 관찰하기 위하여 fMRI 결과 분석에 기존의 box-car function과 DRA 기법이 사용되었다.