• 한국방사선학회논문지
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• 제15권1호
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• pp.1-7
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• 2021

양전자방출단층촬영기기에서 영상을 획득하기 위해서는 동시 측정된 검출기 모듈의 섬광 픽셀의 위치 좌표를 서로 연결하는 과정이 필요하다. 이를 위해서 다수의 섬광 픽셀과 소수의 광센서를 사용하는 검출기 모듈에서는 평면 영상을 획득하여 각 섬광 픽셀의 영역을 나누어 감마선과 상호작용한 섬광 픽셀의 위치를 획득해야 한다. 또는 사용하는 섬광 픽셀의 수와 광센서의 수를 동일하게 구성할 경우는 섬광 픽셀 위치에 대한 위치 좌표를 직접 디지털 신호 좌표로 획득할 수 있다. 다수의 섬광 픽셀과 소수의 광센서를 사용하는 방법은 평면 영상 획득과 영역을 나누는 과정이 필요하며, 디지털 신호 좌표를 직접 획득하는 방법은 다수의 광센서와 신호처리 시스템이 필요하다. 이는 신호처리 과정이 복잡해지며, 비용이 상승하는 문제가 발생한다. 이를 해결하기 위해 본 연구에서는 다수의 섬광 픽셀과 소수의 광센서를 사용하여 평면 영상 및 영역의 분리과정을 수행하지 않고 디지털 신호 좌표를 획득하는 방법을 개발하였다. 최대우도함수를 사용하여 각 섬광 픽셀에서 획득한 신호를 통해 작성된 순람표를 통해 감마선과 상호작용한 섬광 픽셀의 위치 좌표값을 디지털 신호로 획득하는 방법이다. DETECT2000을 사용하여 시뮬레이션을 실시하였으며, 제시한 방법에 대해 검증을 실시하였다. 그 결과 모든 섬광 픽셀에서 정확한 디지털 신호 좌표를 획득할 수 있었으며, 이를 기존 시스템에 적용할 경우 신호처리 과정의 단순화로 보다 빠른 영상획득이 가능할 것으로 판단된다.

• 한국측량학회:학술대회논문집
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• 한국측량학회 2003년도 춘계학술발표회 논문집
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• pp.479-484
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• 2003

The renewal of digital map takes much time and the manual process. LiDAR data allows reduction of time, automatic manner, and acquisition of the precise position. So it is used to renew the digital map of 1:5,000 scale. From the accuracy test results using aerial imagery and digitizing, renewal of digital map are feasible in automatic manner to some extent.

• 대한전자공학회:학술대회논문집
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• 대한전자공학회 1999년도 추계종합학술대회 논문집
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• pp.67-70
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• 1999

DS-CDMA is used to widely spread spectrum for a cellular mobile digital communication that maximizing users- capacity at the limited frequency bandwidth, solving technical matters with the channel. Especially, the capability of a spread spectrum receiver relied on fast code acquisition time at the demodulation. In this paper, we considered that fast code acquisition time when a spread spectrum system is designed, and existed code acquisition system set up one code epoch on a position at initial processing, but the proposed code acquisition system improved that two code epoch are set up at the same time, therefore code acquisition time is diminished in effect. The structure modeling to VHDL language. Its synthesized the synthesized and, is implemented FPGA chip

• 한국공작기계학회논문집
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• 제12권6호
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• pp.77-83
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• 2003

This paper deals with a position control problem of a hydraulic proportional position control system using a nonlinear friction compensation control. As nonlinear friction, stiction and coulomb friction forces are considered and modeled as deadzone and external disturbance respectively. In order to compensate this nonlinearities, we designed the controller which is the adaptive friction compensator using discrete time Model Reference Adaptive Control method in this paper. Digital Signal Processing board is employed for data acquisition and manipulation. The experimental results show that response is slow and steady-state error cannot be compensated properly without friction compensation but this compensator is effective to obtain fast response and good steady-state response.

• 대한전자공학회:학술대회논문집
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• 대한전자공학회 2006년도 하계종합학술대회
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• pp.371-372
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• 2006

In this paper, we propose a method that measures quality of digital correlator. Quality of digital correlator in field of image composition of radio astronomy have as important position for acquisition of radio wave image with high precision. Digital correlator should have wide bandwidth and high precision to study on deep space. Digital correlator, therefore, should be designed to have high speed processing and high precision. But, real time measurement of quality of digital correlator using acquisition data is difficult to compare accuracy of result because digital correlator should process a large quantity of data with high speed. Measurement method of quality, also, has intricate implementation of experiment equipment. this paper present methods that compose experiment equipment without external installation easily and verify quality of digital correlator perfectly.

• 수산해양기술연구
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• 제47권3호
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• pp.257-266
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• 2011

Recently, the manufacturers of life-jacket are very interested in the acquisition of USCG(US Coast Guard) approval because the acquisition of USCG approval has an important role in the purchasing decision of the buyer's. Be based on criterion of USCG, we studied how to predict the change of floating position of human model with life-jacket to verify the backside restore. For this, in this study, the human model and the lifejacket was modeled in three dimension, the application program for prediction of floating position was developed, and plugged-in commercial program.

• 한국측량학회:학술대회논문집
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• 한국측량학회 2003년도 추계학술발표회 논문집
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• pp.219-224
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• 2003

Recently, the number of the use of Digital Photogrammetry is increasing, the Digital Photogrammetry is used for the acquisition of images, remote sensing and three dimension location. Especially, the three dimension location is more activated to use digital camera for the Digital Photogrammetry. The reason is that it is cheap and easy to use and also it has high confidence. Using non-metric digital camera not metric camera, in this research, to get images and apply the images to the Direct Liner Transformation which is one of the techniques in Digital Photogrammetry to get three dimensional location of a point. Ⅰ programmed the procedure with Visual C++ to get the position of points speedly and I tested possibility whether it can analyze the displacement and the existence of structure with measurement system which is structured by a inexpensive non-metric digital camera.

• 한국산업융합학회 논문집
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• 제8권2호
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• pp.69-76
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• 2005

This study for Customer Satisfaction(Customer Focus) by Profit security' in the field Process improvement activity and man-power upgrade by DAS(DATA Acquisition System) in the Plant that is fusion Off Line and On Line(IT), Especially the basic of the most foundation in the beginning Step of Toyota system is 3-jeong(a standard instrument; right volume, right box, right position), 5S(Seiri, Seiton, Seisoh, Seiketsu, Sitsuke ; KAISEN, KANBNA System(for Logistic), Further more KPC has established the digital environment such as CIM ; Computer Integrated Manufacturing), IMS ; Intelligent Manufacturing System ERP ; Enterprise Resource Planning, DAS; Data Acquisition System, Autonomous QC & SPC etc,.) in order to realize the intelligent informatization, which is core base for obtaining the competitive power and for responding to the various 21C management environment in flexibility. In this digital management environment, continuously and powerfully they would advance for becoming the best of the world. For strategic changes to take place in industry 3 key important factors need to be included ; Integration of tasks function and process, Decentralization of information, Responsibility, Finally simplification of products and product structures.

• Nuclear Engineering and Technology
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• 제52권10호
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• pp.2339-2345
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• 2020

Radiation imaging systems consisting of a large number of channels greatly benefit from multiplexing methods to reduce the number of channels with minimizing the system complexity and development cost. In conventional pixelated radiation detector modules, such as anger logic, is used to reduce a large number of channels that transmit signals to a data acquisition system. However, these methods have limitations of electrical noise and distortion at the detector edge. To solve these problems, a multiplexing concept using a digital signal encoding technique based on a time delay method for signals from detectors was developed in this study. The digital encoding multiplexing (DEM) method was developed based on the time-over-threshold (ToT) method to provide more information including the activation time, position, and energy in one-bit line. This is the major advantage of the DEM method as compared with the traditional ToT method providing only energy information. The energy was measured and calibrated by the ToT method. The energy resolution and coincidence time resolution were observed as 16% and 2.4 ns, respectively, with DEM. The position was successfully distributed on each channel. This study demonstrated the feasibility that DEM was useful to reduce the number of detector channels.

• 한국생산제조학회지
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• 제7권4호
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• pp.130-135
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• 1998

This paper deals with a position control problem of a hydraulic proportional position control system using a friction compensation control. There are many nonlinearities in hydraulic systems. With only proportional controller, response is slow and steady-state error cannot be compensated properly. Controller designed in this paper achieves fast transient response through the velocity and acceleration feedback and good steady-state response through the friction compensator. A/D and D/A board is employed for data acquisition and manipulation. The experimental results are compared with computer simulation results using Matlab.