• Transactions on Electrical and Electronic Materials
• /
• 제14권2호
• /
• pp.71-77
• /
• 2013

Advanced semiconductor manufacturing technology requires methods to maximize tool efficiency and improve product quality by reducing process variability. Real-time plasma process monitoring and diagnosis have become crucial for fault detection and classification (FDC) and advanced process control (APC). Additional sensors may increase the accuracy of detection of process anomalies, and optical monitoring methods are non-invasive. In this paper, we propose the use of a chromatic data acquisition system for real-time in-situ plasma process monitoring called the Plasma Eyes Chromatic System (PECS). The proposed system was initially tested in a six-inch research tool, and it was then further evaluated for its potential to detect process anomalies in an eight-inch production tool for etching blanket oxide films. Chromatic representation of the PECS output shows a clear correlation with small changes in process parameters, such as RF power, pressure, and gas flow. We also present how the PECS may be adapted as an in-situ plasma arc detector. The proposed system can provide useful indications of a faulty process in a timely and non-invasive manner for successful run-to-run (R2R) control and FDC.

• 산업경영시스템학회지
• /
• 제41권2호
• /
• pp.74-83
• /
• 2018

It is very crucial activities that Korean army have to detect and recognize enemy's locations and types of weapon of their artillery firstly for effective operation of friendly force's artillery weapons during wartime. For these activities, one of the most critical artillery weapon systems is the anti-artillery radar (hereafter; radars) for immediate counter-fire operations against the target. So, in early wartime these radar's roles are very important for minimizing friendly force's damage because arbiters have to recognize a several enemy's artillery positions quickly and then to take an action right away. Up to date, Republic of Korea Army for tactical artillery operations only depends on individual commander's intuition and capability. Therefore, we propose these radars allocation model based on integer programming that combines ArcGIS (Geographic Information System) analysis data and each radar's performances which include allowable specific ranges of altitude, azimuth (FOV; field of view) and distances for target detection, and weapons types i.e., rocket, mortars and cannon ammo etc. And we demonstrate the effectiveness of their allocation's solution of available various types of radar asset through several experimental scenarios. The proposed model can be ensured the optimal detection coverage, the enhancement of artillery radar's operations and assisting a quick decision for commander finally.

• 전력전자학회:학술대회논문집
• /
• 전력전자학회 2013년도 추계학술대회 논문집
• /
• pp.231-232
• /
• 2013

본 논문에서는 아크검출 알고리즘을 제안한다. 아크를 검출하기 위하여 아크의 전기적 특성 중 하나인 고조파에 대하여 분석하고 아크로 인한 홀수고조파의 변화를 분석하여 아크를 검출할 수 있는 아크 검출 알고리즘을 설계한다. 이를 증명하기 위하여 UL1699에서 제안하는 직렬아크 발생장치를 통하여 아크를 발생시키고 측정한 전류파형을 기반으로 알고리즘을 검증하였다.

• 대한전기학회:학술대회논문집
• /
• 대한전기학회 1997년도 하계학술대회 논문집 D
• /
• pp.883-885
• /
• 1997

High impedance fault(HIF) is random in its behavior even in a similar environment. The detection of Ire HIF has focused on the development of algorithms based on harmonic, parameters of the arc currents. However, a fact that proper selection of the harmonic parameters, rather than algorithm selection, is more important is shown in this paper by applying three different performance evaluation methods on two HIF detection algorithms using eight harmonic parameters.

• 조명전기설비학회논문지
• /
• 제25권7호
• /
• pp.92-96
• /
• 2011

In this paper, in order to reduce the electrical disaster such as electrical fire at traditional markets, we need to develop the ESMS(electrical safety monitoring system) which is able to monitor the power status of electrical equipments. Therefore, for solving the those problems, we developed the detection censor(ZCT, CT) and equipment of data analysis and transmission. The detection censor and equipment are able to monitor the electrical equipments condition(over current, leakage current, arc, etc.). We constructed Test-Bed for testing reliability of the ESMS and obtained certification. And we tested the over current, leakage current and arc under the normal condition.

• 전력전자학회논문지
• /
• 제7권3호
• /
• pp.272-280
• /
• 2002

$CO_2$ GMAW의 연구동향은 주로 용접시에 발생하는 스패터의 저감에 초점이 맞추어져 있으며 이들은 크게 용접 재료의 개선 또는 용접전원의 개선으로 크게 분류될 수 있다. 용접재료 측면에서는 새로운 전극의 재질이나 차폐가스등 새로운 물질에 대한 연구 분야가 있으며 용접전원 측면에서는 아크상태를 최적으로 제어할 수 있는 회로구조 및 제어기법에 대한 연구이다. 본 논문에서는 PWM 인버터형 $CO_2$ GMAW의 금속이행과 및 용접을 위한 여러 제어기법에 대하여 기술하였다. 또한 단락이행시 및 아크재발생시의 제어에 의한 스패터의 저감 방법을 제시하였으며 여러 제어방식과 스패터 저감특성을 비교 연구하였다.

• Journal of Welding and Joining
• /
• 제18권4호
• /
• pp.70-75
• /
• 2000

The weld seam tracking system for arc welding process uses various kinds of sensors such as arc sensor, vision sensor, laser displacement and so on. Among the variety of sensors available, electro-magnetic sensor is one of the most useful methods especially in sheet metal butt-joint arc welding, primarily because it is hardly affected by the intense arc light and fume generated during the welding process, and also by the surface condition of weldments. In this study, a dual-electromagnetic sensor, which utilizes the induced current variation in the sensing coil due to the eddy current variation of the metal near the sensor, was developed for arc welding of sheet metal butt-joints. The dual-electromagnetic sensor thus detects the offset displacement of weld line from the center of sensor head even though there's no clearance in the joint. A set of design variables of the sensor were determined for the maximum sensing capability through the repeated experiments. Seam tracking is performed by correcting the position of sensor to the amount of offset displacement every sampling period. From the experimental results, the developed sensor showed the excellent capability of weld seam detection when the sensor to workpiece distance is near less than 5 mm, and it was revealed that the system has excellent seam tracking ability for the butt-joint of sheet metal.

• International Journal of Korean Welding Society
• /
• 제2권2호
• /
• pp.51-56
• /
• 2002

The weld seam tracking system for arc welding process uses various kinds of sensors such as arc sensor, vision sensor, laser displacement sensor and so on. Among the variety of sensors available, electro-magnetic sensor is one of the most useful methods especially in sheet metal butt-joint arc welding, primarily because it is hardly affected by the intense arc light and fume generated during the welding process, and also by the surface condition of weldments. In this study, a dual-electromagnetic sensor, which utilizes the induced current variation in the sensing coil due to the eddy current variation of the metal near the sensor, was developed for arc welding of sheet metal I-butt joints. The dual-electromagnetic sensor thus detects the offset displacement of weld line from the center of sensor head even though there's no clearance in the joint. A set of design variables of the sensor was determined far the maximum sensing capability through the repeated experiments. Seam tracking is performed by correcting the position of sensor to the amount of offset displacement every sampling period. From the experimental results, the developed sensor showed the excellent capability of weld seam detection when the sensor to workpiece distance is near less than 5 ㎜, and it was revealed that the system has excellent seam tracking ability for the I-butt joint of sheet metal.

• Current Photovoltaic Research
• /
• 제8권4호
• /
• pp.114-119
• /
• 2020

In this study, Mitigation of Potential-induced degradation (PID) for PERC solar cells using SiO2 Structure of ARC layer. The conventional PID test was conducted with a cell-level test based on the IEC-62804 test standard, but a copper PID test device was manufactured to increase the PID detection rate. The accelerated aging test was conducted by maintaining 96 hours with a potential difference of 1000 V at a temperature of 60℃. As a result, the PERC solar cell of SiO2-Free ARC structure decreased 22.11% compared to the initial efficiency, and the PERC solar cell of the Upper-SiO2 ARC structure decreased 30.78% of the initial efficiency and the PID reliability was not good. However, the PERC solar cell with the lower-SiO2 ARC structure reduced only 2.44%, effectively mitigating the degradation of PID. Na+ ions in the cover glass generate PID on the surface of the PERC solar cell. In order to prevent PID, the structure of SiNx and SiO2 thin films of the ARC layer is important. SiO2 thin film must be deposited on bottom of ARC layer and the surface of the PERC solar cell N-type emitter to prevent surface recombination and stacking fault defects of the PERC solar cell and mitigated PID degradation.

• International Journal of Safety
• /
• 제11권2호
• /
• pp.15-21
• /
• 2012

This paper is aimed to develop an electrical fire detection system (EFDS) which can analyze the possibility of electrical fire for overcurrent, leakage current and arc signals of panel board in traditional market shop. The EFDS adopted fuzzy logic and precursory data for overcurrent, leakage current and arc signals to evaluate the possibility of electrical fire. The signals are obtained directly from panel board in traditional market shops and fuzzy membership function is obtained from experiment, simulation, expert's advice. The overcurrent data is acquired by thermal data of normal and abnormal states (partial disconnection) on the insulated electrical wire, in accordance with the increase of the current signal, The leakage current data is obtained under various environments. The arc signal is acquisited by waveforms of instantaneous value in time domain and frequency band in frequency domain. The Fuzzy algorithm for DB of EFDS consists of fuzzification, inference engine by Mamdani's method and defuzzification by center of gravity method. In order to verify the performance and reliability of EFDS, it was applied to Jeon-Ju traditional market shops (90 shops) in Korea. Results show that EFDS in this paper is useful in alarming the fire case, which will prevent severe damage to human beings and properties, and reduce the electrical fires in a vulnerable area of electrical disaster.