• Journal of the Optical Society of Korea
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• v.20 no.4
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• pp.524-529
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• 2016

Diagnostic sensors are demanded during plasma processes. Holograms of plasma taken with laser light without a reference beam were used to monitor behaviors of charged particles produced in nitrogen plasma as a function of electrode temperature ranging between 50 and 300℃. Holograms were characterized as a function of the pixel sum and grayscale value. Pixel sum calculated in identified grayscale ranges strongly correlated with ion density and emitted light intensity measured with a langmuir probe and optical emission spectroscopy, respectively. The performance was further evaluated with data acquired as a function of N₂ and NH₃ flow rates and improved correlations were observed in the new grayscale range. The confirmed correlations indicate that a hologram is a viable means to diagnose behaviors of plasma particles such as ions. Underlying principles are discussed in view of particle and charge composing vacuum and light.

• Journal of the Korean Society for Precision Engineering
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• v.15 no.1
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• pp.19-25
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• 1998

Remote fault diagnosis and maintenance system using general telecommunication network is necessary for an effective fault diagnosis and higher productivity of NC machine tools. In order to monitor machine tool condition and diagnose alarm states due to electrical and mechanical faults, a remote data communication system for monitoring of NC machine fault diagnosis and status is developed. The developed system consists of (1) remote communication module among NC's and host PC using PSTN. (2) 8 channels analog data sensing module, (3) digital I/O module for control or NC machine, (4) communication module between NC machine and remote data communication system via RS-232C, and (5) software man-machine interface. Diagnostic monitoring results generated through a successive type inference engine are displayed in user-friendly graphics. The validity and reliability of the developed system is verified to be a powerful commercial version on a vertical machining center through a series of experiments.

• Proceedings of the KIEE Conference
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• 1998.07e
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• pp.1717-1720
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• 1998

In pumped storage Generator-motor stator windings gradually deteriorates due to mechanist, thermal, electrical stresses. These stresses combine to result in loose windings, delamination of the stator insulation and/or electrical tracking of the endwinding, all of which can lead to stator insulation failures. Since the degration of generator-motor is gradually occurred, regular inspection system is necessary to monitor degrading. The result of this diagnosis is a basic for the maintxnance of generator-motor.

• Korean Journal of Veterinary Service
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• v.27 no.2
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• pp.147-151
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• 2004

The objective of present study was to assess the diagnostic value of the concentration of haptoglobin, one of a series of acute phase proteins that is found in the blood of both humans and animals. A total of 79 random horse sera(10 dam and 69 foals) with clinically normal were analyzed by ELISA. The mean serum concentrations of haptoglobin of dam and foals were 1.67${\pm}$0.52mg/ml(range 1.08∼2.12 mg/ml), 1.65${\pm}$0.50 mg/ml(range 0.50∼2.66 mg/ml), respectively. These results may provide basic information for developing a useful marker system to monitor infections early in horses.

• KEPCO Journal on Electric Power and Energy
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• v.6 no.1
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• pp.49-52
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• 2020

Since power plant is an important system to provide electricity, it is necessary to monitor it in order to operate safely. Much information related with machine diagnosis exists in written form instead of digital data. So, it causes difficulties of analyzing and finding solutions. Rulebased expert system can provide flexible and effective solutions to users. In this paper, Recursive Bayesian Estimation is applied in order to increase accuracy of solutions.

• Electronics and Telecommunications Trends
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• v.21 no.2 s.98
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• pp.170-183
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• 2006

모뎀 진단/감시 장치(DM)는 기지국 DM 데이터 수집부와 단말 DM 데이터 수집부로각각 구분되어 DM 장치 내에서 기지국/단말 모뎀 플랫폼을 수용한다. 기지국 변조기, 기지국 동기, 기지국 채널 디코더, 기지국 복조기의 데이터는 기지국 DM 데이터 수집부에서 수집하고, 단말 변조기, 단말 동기, 단말 채널 디코더, 단말 복조기의 데이터는 단말 DM 데이터 수집부에서 수집하여 각각 수집된 데이터를 호스트 PC에서 분석하여 물리 계층 송수신 데이터 및 각종 통계 정보를 사용자 및 운용자가 확인할 수 있도록GUI로 화면에 표시해 준다. 모뎀 진단/감시 장치(DM)는 무선 전송 시스템(HM20)MIMO 구조 기지국/단말 모뎀의 물리 계층에 대한 상태 진단 및 감시 기능을 수행하여 모뎀 개발 과정에서 개발자에게 디버깅을 쉽게 하기 위한 장치로 사용된다. 또한 기지국 모뎀과 단말 모뎀의 유지 보수시 오류 발견을 위한 장치로 사용하기 위함이다.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2004.07a
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• pp.481-484
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• 2004

A form of measured temperature distribution to estimate condition of a electrical apparatus is a absolute reference for condition of the apparatus, time rate of transition, and difference between reference and currently temperature. Because passive thermography which has not injection of external thermal stimulation shows difference of temperature being on surface of a structure and temperature difference between the structure and back ground, the result could apply only to estimation or monitor for condition of terminal relaxation and overload related with temperature rising. However, a thermal flow in active thermography is differently generated by structure and condition of surface and subsurface. This paper presents the nondestructive testing using the properties and includes the results by heat injection and cooling to the apparatus. The buried discontinuity of subsurface could be detected by these techniques.

• Parasites, Hosts and Diseases
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• v.56 no.5
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• pp.477-485
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• 2018

Arthropod-borne viruses (Arboviruses) are transmitted by arthropods such as Culicoides biting midges and cause abortion, stillbirth, and congenital malformation in ruminants, apparently leading to economic losses to farmers. To monitor the distribution of Culicoides and to determine their relationship with different environmental conditions (temperature, humidity, wind speed, and altitude of the farms) on 5 cattle farms, Culicoides were collected during summer season (May-September) in 2016 and 2017, and analyzed for identification of species and detection of arboviruses. About 35% of the Culicoides were collected in July and the collection rate increased with increase in temperature and humidity. The higher altitude where the farms were located, the more Culicoides were collected on inside than outside. In antigen test of Culicoides against 5 arboviruses, only Chuzan virus (CHUV) (2.63%) was detected in 2016. The Akabane virus (AKAV), CHUV, Ibaraki virus and Bovine ephemeral fever virus (BEFV) had a positive rate of less than 1.8% in 2017. In antigen test of bovine whole blood, AKAV (12.96%) and BEFV (0.96%) were positive in only one of the farms. As a result of serum neutralization test, antibodies against AKAV were generally measured in all the farms. These results suggest that vaccination before the season in which the Culicoides are active is probably best to prevent arbovirus infections.

• The Transactions of the Korean Institute of Electrical Engineers P
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• v.60 no.3
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• pp.114-119
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• 2011

Large Power transformer is a complex and critical component of power plant and consists of cellulosic paper, insulation oil, core, coil etc. Insulation materials of transformer and related equipment break down to liberate dissolved gas due to corona, partial discharge, pyrolysis or thermal decomposition. The dissolved gas kinds can be related to the type of electrical faults, and the rate of gas generation can indicate the severity of the fault. The identities of gases being generated are using very useful to decide the condition of transformation status. Therefore dissolved gas analysis is one of the best condition monitoring methods for power transformer. Also, on-line multi-gas analyzer has been developed and installed to monitor the condition of critical transformers. Rogers method, IEC method, key gas method and Duval Triangle method are used to failure diagnosis typically, and those methods are using the ratio or kinds of dissolved gas to evaluate the condition of transformer. This paper analyzes the reliability of transformer diagnostic methods considering actual dissolved gas concentration. Fault diagnosis is performed based on the dissolved gas of five transformers which experienced various fault respectively in the field, and the diagnosis result is compared with the actual off-line fault analysis. In this comparison result, Diagnostic methods using dissolved gas ratio like Rogers method, IEC method are sometimes fall outside the ratio code and no diagnosis but Duval triangle method and Key gas method is correct comparatively.

• Korean Journal of Health Education and Promotion
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• v.31 no.4
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• pp.1-10
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• 2014

Objectives: The effectiveness of Blood ${\beta}$-ketone testing by using self-monitoring strip on diabetic patients. Methods: Clinical effectiveness of blood ${\beta}$-ketone testing was assessed through correlation with reference test that measured blood ${\beta}$-ketone value through gas chromatography or enzyme method, diagnostic accuracy, time taken for the test and time taken for confirmative diagnosis of diabetic ketosis by selecting literatures on researches that conducted this test on ketosis(suspected) patients or diabetic ketosis(suspected) patients. Each of the stages from literature search to application of selection standards and extraction of data were carried out independently by the Subcommittee along with 2 researchers. Results: 7 reports were selected. ${\beta}$-ketone testing displayed high level of correlation in the range of r=0.92~0.99 with test using enzyme method as the reference standard. Regarding the diagnostic accuracy, sensitivity of 0.82, specificity of 0.74. The time taken for the test was 30seconds for the index test, which is shorter than reference standard test. Conclusion: Blood ${\beta}$-ketone testing was assessed to be a safe and effective test to monitor ketosis and assess the level of risk of ketosis by measuring the blood ${\beta}$-ketone on ketosis patients and diabetic ketosis patients since it has high level of correlation with reference test and short period of testing.