• 한국전자파학회논문지
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• 제15권8호
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• pp.744-751
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• 2004

본 논문에서는 RF소자들의 테스트시 비용 절감을 극대화 할 수 있는 저가형 고속 RF 자동화 테스트 시스템(Automatic Test Equipment, ATE)의 제작에 관하여 다루어진다. 제작된 RF ATE는 고속의 스위칭 시간과 고정밀 디지타이저를 포함한 16개의 독립적인 RF 입출력 단자를 갖고 있으며 산업 표준인 VXI(Versus module eXtensions for Instrument)와 GPIB(General Purpose Interface Bus) 인터페이스를 사용하여 구성된다. 또한 소자의 생산효율을 극대화하기 위하여 동시에 4개의 소자를 테스트할 수 있도록 시스템이 구성된다. 마지막으로 현재 가격 경쟁이 상당히 심한 소자 중 하나인 RF 전력증폭모듈올, 제작된 RF ATE를 이용하여 테스트를 진행하여 시스템 성능을 검증한다.

• KSBB Journal
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• 제15권2호
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• pp.139-144
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• 2000

알콜증류폐액에 빵효모를 배양하는 중에 glucose와 ammon-ium을 자동첨가하여 균체량을 효율적으로 증가시킴으로써 폐액의 재이용성을 향상시키고자 하였다. Glucose는 DO를 제어파라미터로 하는 제어방법을 사용하여 116 mg/L 이하로 자동제어하였다. Ammonium의 경우에는 FIA를 이용한 온라인 자동계측제어장치와 프로그램을 이용하여 배양액의 ammon-ium 농도를 자동분석하고 제어하였으며, ammonium 농도를 류.0~27.7 mM의 낮은 농도범위로 유지시킬 수 있었다. Ammo-nium 농도를 제어한 본 실험의 최대비증식속도는 0.21 hr-1이었고, 대당균체수율은 약 0.78 g/g 으로서 ammonium 농도를 제어하지 않은 경우에 비하여 대당균체수율은 약 1.4배, 최대비증식속도는 1.2배 더 높아졌으므로 ammonium 제어에 의하여 균의 glucose 이용효율이 더욱 향상되었다. 대암모늄균체수율은 약 11.3 g/g 이었다. Glucose와 ammonium을 첨가함으로써 균체량을 18.5 g/L 까지 높일 수 있었으며, 이는 첨가하지 않은 경우보다 7.1배 더 높은 균체량에 해당한다. Glucose와 ammonium의 농도를 낮게 유지시킬 수 있었으므로 두가지 영양성분의 경제적인 공급이 가능하였다.

• 산업공학
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• 제21권4호
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• pp.378-384
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• 2008

Small sized companies have not been successful in systematically applying statistical process control because of insufficient human resources. In this paper we present a case study of automatic checking system for a small sized company which produces various types of gears. A systematic way of automatically measuring gears is proposed and statistical analysis methods are presented. To reduce variation in the measurement data, a standard operating procedure is also proposed. This case study can be helpful to quality assurance practitioners of small sized companies who are willing to develop checking or inspection systems for their products.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2015년도 제46회 하계학술대회
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• pp.707-708
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• 2015

This paper proposes a method for improving efficiency of high-voltage motors off-line insulation diagnostic test. The conventional manual test method has measurement errors and excessive processing time. We developed the KITAS system and solved these problems by using the instrument remote control and communication technology. The result of proficiency testing by interlaboratory comparisons using Power Factor Tip-Up test was '${\mid}E_n{\mid}$ < 1'. It was possible to confirm the validity of acquired data from the KITAS and establish a remote diagnostic system for easy access without physical limitations.

• 한국의학물리학회:학술대회논문집
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• 한국의학물리학회 2002년도 Proceedings
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• pp.237-240
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• 2002

Knowing the dose distribution in a tissue is as important as being able to measure exposure or absorbed dose in radiotherapy. Since the Dry Imager spread, the wet type automatic processor is no longer used. Furthermore, the waste fluid after film development process brings about a serious problem for prevention of pollution. Therefore, we have developed a measurement method for the dose distribution (CR dosimetry) in the phantom based on the imaging plate (IP) of the computed radiography (CR). The IP was applied for the dose measurement as a dosimeter instead of the film used for film dosimetry. The data from the irradiated IP were processed by a personal computer with 10 bits and were depicted as absorbed dose distributions in the phantom. The image of the dose distribution was obtained from the CR system using the DICOM form. The CR dosimetry is an application of CR system currently employed in medical examinations to dosimetry in radiotherapy. A dose distribution can be easily shown by the Dose Distribution Depiction System we developed this time. Moreover, the measurement method is simpler and a result is obtained more quickly compared with film dosimetry.

• KSBB Journal
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• 제23권4호
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• pp.317-322
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• 2008

본 연구를 통하여 자체 구동형 모터를 갖는 BOD 센서를 개발하였으며, 6,000초 이상 측정한 결과 안정적인 측정이 가능함을 확인하였다. 응답시간은 30초 이내, 재현성은 1 ppm 이내, 선형성은 99%의 우수한 성능을 갖는 BOD 센서를 개발하였다. 최대 산소소모속도 (Maximum Oxygen Uptake Rate, $OUR_{max}$)와 $BOD_5$ 상관관계는 $BOD_5$ (ppm)=-2,490+33,889 ($OUR_{max}$)로서, 95.6%의 우수한 선형성을 보였다. 자체구동형 BOD 센서를 이용하여 시료의 전처리부터 BOD의 측정까지 자동으로 제어 및 측정되는 시스템을 구성하였다. 본 연구를 통하여 최대 산소소모속도 ($OUR_{max}$)와 $BOD_5$ 상관관계를 구한 후 수분내에 $BOD_5$ 값을 예측할 수 있었다.

• 펄프종이기술
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• 제36권1호
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• pp.1-8
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• 2004

One of the most frequently used method for measurement of the degree of sizing (viz., hydrophobicity) is the Stockigt test. However, the Stockigt test was influenced by various factors such as dropping height, dropping amount, dropping speed and viewing angle. The resultant data of the sizing degree on the same specimen also varied according to different testers. Thus, the Stockigt test should be modified to be regarded as a highly reliable and reproducible standard method. For modifying the Stockigt test, it was required to quantify red coloration by reaction between 1％ ferric chloride and 2％ ammonium thiocyante during Stockigt testing. The cameras capturing the serial images during the red coloration process were the CMOS (Complementary Metal Oxide Semiconductor)-type and CCD (Charge Coupled Device)-type cameras. For measurement based on KS M 7025, the CCD-type camera must be used due to its high resolution, and on the other hand, for measurement based on Tappi Useful Method 429, the CMOS-type camera may be used owing to its low resolution. It was needed to covert the RGB values of a droplet image into HSV(Hue, Saturation, and Value) values because the human eyes are much closer to HSV than RGB. Among HSV values, the Hue value was accepted as the most reliable index consistent with the red coloration process by excluding the surrounding conditions such as light, tester's movement etc.

• 한국진공학회:학술대회논문집
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• 한국진공학회 2012년도 제42회 동계 정기 학술대회 초록집
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• pp.184-184
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• 2012

We proposed a new measurement method of cutoff probe using the reactance spectrum of the plasma in cutoff probe system instead of transmission spectrum. The high accurate reactance spectrum of the plasma which is expected in previous circuit simulation of cutoff probe [1] was measured by using the automatic port extension method of the network analyzer. The measured reactance spectrum is good agreement with E/M wave simulation result (CST Microwave Studio). From the analysis of the measured reactance spectrum based on the circuit modeling, not only the electron density but also electron-neutral collision frequency can be simply obtained. The obtained results of electron density and e-n collision frequency were presented and discussed in wide range of experimental conditions, together with comparison result with previous methods (a previous cutoff probe using transmission spectrum and a single langmuir probe).

• Journal of Platform Technology
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• 제11권2호
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• pp.66-75
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• 2023

첨단장비 도입 및 기술의 발전으로 수문조사 측정 기술은 향상되었으나 여전히 수문조사 시 많은 인력과 시간이 필요하며, 업무 규모와 범위에 비해 투입되는 인력은 매우 제한적이다. 또한, 자동유량 측정시설이 운영되고 있지만 현장 조건의 제한되기 때문에 전국으로 확대하기가 어렵다. 따라서 수문조사를 위해 측정 기술 자체보다는 운영 인프라 및 환경 개선이 필요하다. 또한 유량조사 측면에서 수위-유량 관계식의 정확도 재고와 업무 효율성 증진을 위해 실시간 수위 정보를 이용한 조사 스케줄링이 필요하다. 따라서 본 논문에서는 국내 수문조사 관련 연구 파악 및 수문조사의 경제성과 효율성 증대를 위하여 Open API 기반의 실시간 수위 정보를 활용한 수문조사 스케줄링 시스템을 구현하였다.

• 한국정밀공학회지
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• 제20권6호
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• pp.88-95
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• 2003

This paper presents the measurement and correction method of PCB alignment errors for PCB screen printer. Electronic equipment is getting smaller and yet must satisfy high performance standard. Therefore, there is a great demand for PCB with high density. However conventional PCB screen printer doesn't have enough accuracy to accommodate the demand fur high-resolution circuit pattern and high-density mounting capacity of electronic chips. It is because the alignment errors of PCB occur when it is loaded to the screen printer. Therefore, this study focuses on the development of the system which is able to measure and correct alignment errors with high-accuracy. An automatic optical inspection part measures the PCB alignment errors using machine vision, and the high-accuracy 3-axis stage makes correction for these errors. This system used two CCD cameras to get images of two fiducial marks of PCB. The geometrical relationship between PCB, cameras, and xy$\theta$ stage is derived, and analytical equations for alignment errors are also obtained. The unknown parameters including camera declining angles and etc. can be obtained by initialization process. Finally, the proposed algorithm is verified by experiments by using test bench.