• 대한전자공학회:학술대회논문집
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• 대한전자공학회 2003년도 하계종합학술대회 논문집 II
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• pp.1109-1112
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• 2003

본 연구는 switching mode 의 Power NMOSFET failure mode 에 관하여 분석하고 원인을 규명하였다. 분석된 power NMOSFET은 30V급이며, vender A의 상용화 제품이다. 발생한 failure mode는 power switch 회로에서 특정 ID 를 detect 하지 못하는 mode 였다. 측정결과 source voltage 가 저하되었으며, power NMOSFET DC 동작특성 분석 결과 Vgs 변화에 따라 Id 가 저하되었다. Fail 된 power MOSFET 특성값 reference는 동일 LOT의 양품을 선정하였다. De-cap후 Inversion 과 Accumulation mode 별로 Photoemission spectrum analyzer(PSA) 분석 방법을 적용하였다. 결과 accumulation mode 에서 intensity가 감소하였으며, forward diode mode에서 국소적으로 변화하는 영역이 검출되었다. SEM 분석결과 gate metal 과 source metal 의 micro-contact 이 이루어져 있었다. 이 경우 gate metal 과 source metal 사이 close loop 를 형성하여 gate charge량을 변화시켜 power NMOSFET의 출력을 저하하는 failure mode가 발생됨을 분석할 수 있었다.

• 대한전기학회:학술대회논문집
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• 대한전기학회 1999년도 추계학술대회 논문집 학회본부 C
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• pp.1015-1018
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• 1999

Partial discharge patterns were analyzed in the pumped storage generator stator winding. These were measured using partial discharge analyzer(PDA) and digital partial discharge detector(PDD). Slot discharge was discovered in phase A. Discharges at conductor surface were occurred in phase B and in Phase C. Partial discharge patterns from on-line PDA system were compared with those off-line PDD system. The results of two systems are very same in phase A, B and C.

• Journal of electromagnetic engineering and science
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• 제17권4호
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• pp.208-220
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• 2017

This paper proposes an experimental optimization method for a wireless power transfer (WPT) system. The power transfer characteristics of a WPT system with arbitrary loads and various types of coupling and compensation networks can be extracted by frequency domain measurements. The various performance parameters of the WPT system, such as input real/imaginary/apparent power, power factor, efficiency, output power and voltage gain, can be accurately extracted in a frequency domain by a single passive measurement. Subsequently, the design parameters can be efficiently tuned by separating the overall design steps into two parts. The extracted performance parameters of the WPT system were validated with time-domain experiments.

• 한국시뮬레이션학회:학술대회논문집
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• 한국시뮬레이션학회 2005년도 춘계학술대회 논문집
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• pp.129-133
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• 2005

This paper describes the methodology of connecting MASTER (Multi-purpose Analyzer for Static and Transient Effects of Reactors) to simulator system, system configuration, and previous test. The actual simulator environment for Youngkwang Unit1 has been developed. It is impossible for the simulator server to execute MASTER code by limitation of computer performance. So, environment of distributed system was developed, and it had a synchronization task. As MASTER and simulator module should be synchronized in different device, the connection of communication was tested and verified.

• 한국광학회:학술대회논문집
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• 한국광학회 2009년도 창립 20주년기념 특별학술발표회
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• pp.121-122
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• 2009

• 동의생리병리학회지
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• 제21권6호
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• pp.1381-1387
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• 2007

Pulse diagnosis that is one of important examination methods in traditional oriental medicine has been investigated for the standardization in many ways. Pulse analyzer device and clinical studies have been tried for this purpose. Additionally, literature study has significance for this standardization. In this study, we analyzed pulse types in literatures from the viewpoint of physics. We refered to Maijing, Maijue, siyanjuyao, Binhumaixue, Yixuerumen, zhenjiazhengyan. We established some physical factors for analysis. This factors that can be detected through pulse analyzer are depth, speed, power, width, and length. In this study, we defined 18 kinds of pulse types among 28 total types by physical factors. Furthermore, 6 kinds of pulse types were classified as basic pulse from these. The results of this study will improve the pulse analyzer to detect these pulse types.

• 대한전기학회:학술대회논문집
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• 대한전기학회 1997년도 추계학술대회 논문집 학회본부
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• pp.479-483
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• 1997

In general, motor parameters can be divided into mechanical/electrical parameters and harmonic parameters. Mechanical/electrical parameters identification of motor have been studying systematically for a long time. But, systematical study on harmonic parameters analysis for efficient motor drive system are very poor. The goal of this paper is to propose analyzing method of harmonic parameters for motor drive system with various experimental graphic screens and numerical results and to develope harmonic parameters analyzer. A developed analyzer is made up 586-PC and DSP (digital signal processor) board, motor drive system, power and harmonic parameters analyzing software for windows. Harmonic parameters are analyzed using correlation signal processing techniques based on the correlation between voltage and current waveforms. Analysis results are visualized by 3-D current coordinates, and it is compared and evaluated with conventional time/frequency domain. To verify the validity of the proposed system, 1/4HP capacitor run type single phase induction motor and thyristor speed controller is used for analyzing. Harmonic parameters of motor drive system is analyzed and verified, with varying fire angle of thyristor speed controller, and the proposed approach is to confirm validity.

• 대한의용생체공학회:학술대회논문집
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• 대한의용생체공학회 1996년도 춘계학술대회
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• pp.175-178
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• 1996

The purpose of this thesis is the propose of various signal processing algorithm for the ECG(electrocardiogram) and the design of realtime automated ECG analyzer feasible with these algorithms. The algorithms are composed of (1)filtering procedure fer the estimation and removal of baseline drift, 60Hz power line interference, and muscle artifacts (2)detection procedure of QRS complex and P wave (3)typification procedure for the pattern classification according to the morphologies (4) selection of representative beat, significant point and wave boundary decision procedure and (5) parameter extraction and diagnosis procedure. All verifications are carried out between the algorithms proposed in this paper and other algorithms already proposed by many researchers, for the objective comparison in each procedure. The efficiency of proposed algorithms are demonstrated with the aid of internationally validated CSE database and the performances of filtering procedure are compared on artificial noise signal as well as actual ECG signals with appropriate noise components. for the comparison on the performance of designed automated ECG analyzer, the diagnosis results were compared with ECG analyzer manufactered by Fukuda denshi in Japan.

• 사상체질의학회지
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• 제35권4호
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• pp.1-9
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• 2023

Objectives This study is designed to examine the relationship between healthy state (完實無病) of Sasang constitution and pulse wave (脈波). Methods The subjects were 100 patients who were diagnosed with Sasang constitution and underwent pulse analyzer test. The status of urination, defecation, perspiration, and digestion was classified as good, intermediate, and poor. The power, depth, speed, and roughness of pulse waves (脈波) were analyzed. Results Patients with poor digestion had relatively powerless pulse wave (無力脈). Soeumin patients had a higher rate of poor digestion compared to other constitutions. Soyangin patients had a higher rate of poor perspiration compared to other constitutions. Soyangin with poor defecation had relatively choppy pulse wave (澁脈), and poor perspiraton had relatively slippery (滑脈). Soeumin patients with poor digestion had relatively powerless pulse wave (無力脈). Conclusions The pulse wave of poor healthy state (完實無病) is an expression of a pathological syndromes (病證) caused by lack of or damage to healthy energy (保命之主). It was concluded that the pulse analyzer can be used to evaluate healthy state (完實無病).

• Nuclear Engineering and Technology
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• 제56권5호
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• pp.1836-1844
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• 2024

The use of digital systems in radiation science has been increased last years in the different knowledge areas, as a detectors, spectrometry, spectroscopy, simulation, etc. This manuscript presents the design and implementation of a low-cost, fully portable multi-channel analyzer for nuclear spectrometry (in situ). The development is based on a 32-bit microcontroller with ARM Cortex-M7, this design is able to digitize and analyze pulses from a radiation detector without the need to transform the input signal with some filter, obtains the maximum height of each of the digitized pulses, segmenting the information into channels to form a histogram and visualizing the LCD screen incorporated in the system. A continuous digitization methodology was used, which is in charge of the DMA and an ADC with a resolution of 12 bits at a speed of 3.6 MSPS. The system has a compact design and can open and save spectra in an SD memory built into the system. The MCA in MCU was tested with a NaI(Tl) Scintillation radiation detector, which allowed us to determine that the spectra obtained are similar compared to commercial MCA's. The results obtained show that the MCA in MCU is efficient for nuclear spectrometry, in addition to being very economical and low power consumption.