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論文

論文
Chomsuwan, K. ; Fukuda, Y. ; Yamada, Sotoshi ; Iwahara, Masayoshi ; Wakiwaka, H. ; Shoji, S. ; 山田, 外史 ; 岩原, 正吉
出版情報: Applications of Electrimagnetic Phenomena in Electrical and Mechanical Systems / Studies in Applied Electromagnetics and Mechanics.  15  pp.217-222,  2005.  The Japan Society of Applied Electromagnetics and Mechanics (JSAEM) = 日本AEM学会
URL: http://hdl.handle.net/2297/00049226
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論文
Yamada, Sotoshi ; Gooneratne, C. ; Chomsuwan, K. ; Iwahara, Masayoshi ; Kakikawa, Makiko
出版情報: AIP Conference Proceedings.  975  pp.873-880,  2008-01-01.  AIP Publishing
URL: http://hdl.handle.net/2297/48632
概要: This paper describes a new application of a spin-valve type giant magnetoresistance sensor in the biomedical field. The hyperthermia treatment, based on the hysteresis loss of magnetite under external ac fields, requires determination of the content density of magnetite injected inside the body to control the heat capacity. We propose a low-invasive methodology to estimate the density of magnetite by measuring magnetic fields inside the cavity. For this purpose, we investigated the relationship between the density of magnetite and the magnetic fields, and developed a needle-type magnetic probe with a giant magnetoresistance sensor for low-invasive measurement. The experimental results demonstrate the possibility of estimating the low-concentration density of magnetite injected into the body. © 2008 American Institute of Physics. 続きを見る
3.

論文

論文
Chomsuwan, K. ; Yamada, Sotoshi ; Iwahara, Masayoshi
出版情報: IEEE Transactions on Maggetics.  43  pp.2394-2396,  2007-06-01.  Institute of Electrical and Electronics Engineers IEEE
URL: http://hdl.handle.net/2297/48303
概要: This paper describes the improvement on the defect detection performance of printed circuit board (PCB) inspection based on the eddy-current testing (ECT) technique with the multispin-valve giant magnetoresistance (SV-GMR) sensor. To obtain the ECT signal in the same scanning line, SV-GMR sensors are mounted on the exciting coil in the same column parallel with the scanning direction. Harmonic analysis based on the Fourier transform is used to analyze the signal from the SV-GMR sensor in order to increase scanning speed. Then signal averaging is applied to the ECT signal in order to improve the signal-to-noise ratio. Experimental results are performed to verify the inspection performance. 続きを見る
4.

論文

論文
Yamada, Sotoshi ; Chomsuwan, K. ; Fukuda, Y. ; Iwahara, Masayoshi ; Wakiwaka, H. ; Shoji, S.
出版情報: IEEE Transactions on Maggetics.  40  pp.2676-2678,  2004-07-01.  Institute of Electrical and Electronics Engineers IEEE
URL: http://hdl.handle.net/2297/48307
概要: This paper proposes an eddy-current testing (ECT) probe composed of a spin-valve giant magnetoresistance (SV-GMR) sensor and a meander coil for the inspection of bare printed circuit board. The SV-GMR sensor serves as a magnetic sensor for the ECT probe to sense the variation of the magnetic field distribution occurred on the printed circuit board. The SV-GMR sensor is used specifically to detect the changing magnetic field distribution occurred at the defect point. The characteristics of the proposed probe are discussed in this paper. The comparisons of signal-to-noise ratios obtained from ECT probe with SV-GMR sensor and with solenoid coil verify that the applying of SV-GMR sensor to the ECT probe can improve the PCB inspection results. 続きを見る
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論文

論文
Chomsuwan, K. ; Yamada, Sotoshi ; Iwahara, Masayoshi ; Wakiwaka, H. ; Shoji, S.
出版情報: IEEE Transactions on Maggetics.  41  pp.3619-3621,  2005-10-01.  Institute of Electrical and Electronics Engineers IEEE
URL: http://hdl.handle.net/2297/48328
概要: High-density double-layer printed circuit board (PCB) inspection based on the eddy-current testing (ECT) technique is proposed in this paper. The ECT probe, which consisted of a planar meander exciting coil and spin-valve giant magnetoresistance (SV-GMR) sensor array, is used for this propose. Defects on both the top- and bottom-layer of the high-density double-layer PCB are examined by the ECT technique with scanning over either the top or bottom layer. The characteristics of the proposed ECT probe for high-density double-layer PCB inspection are studied. The inspection results of the high-density double-layer PCB model verify that applying the ECT technique enables identification of the defects of both the top and bottom layer with one-side scanning. 続きを見る
6.

論文

論文
Yamada, Sotoshi ; Chomsuwan, K. ; Hagino, T. ; Tian, H. ; Minamide, K. ; Iwahara, Masayoshi
出版情報: IEEE Transactions on Maggetics.  41  pp.3622-3624,  2005-10-01.  Institute of Electrical and Electronics Engineers IEEE
URL: http://hdl.handle.net/2297/48329
概要: This paper describes the detection of conductive microbeads (PbSn) based on eddy-current testing (ECT) technique. High-frequency magnetic field applied to the conductive microbeads enables spin-valve giant magnetoresis-tance (SV-GMR) sensor to detect the magnetic fields occurred from eddy currents flowing in the conductive microbeads. In this paper, analysis of these magnetic fields by an analytical method is discussed and compared with experimental results. 続きを見る
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論文

論文
Chomsuwan, K. ; Yamada, Sotoshi ; Iwahara, Masayoshi
出版情報: IEEE Transactions on Magnetics.  43  pp.2394-2396,  2007-06-01.  IEEE
URL: http://hdl.handle.net/2297/6913
概要: 金沢大学環日本海域環境研究センター生体機能計測研究部門<br />This paper describes the improvement on the defect detection performance of printed cir cuit board (PCB) inspection based on the eddy-current testing (ECT) technique with the multispin-valve giant magnetoresistance (SV-GMR) sensor. To obtain the ECT signal in the same scanning line, SV-GMR sensors are mounted on the exciting coil in the same column parallel with the scanning direction. Harmonic analysis based on the Fourier transform is used to analyze the signal from the SV-GMR sensor in order to increase scanning speed. Then signal averaging is applied to the ECT signal in order to improve the signal-to-noise ratio. Experimental results are performed to verify the inspection performance. © 2007 IEEE. 続きを見る
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論文

論文
Yamada, Sotoshi ; Chomsuwan, K. ; Iwahara, Masayoshi
出版情報: Proceedings of IEEE Sensors.  pp.927-930,  2006-10-01.  Institute of Electrical and Electronics Engineers (IEEE)
URL: http://hdl.handle.net/2297/11877
概要: 金沢大学環日本海域環境研究センター生体機能計測研究部門<br />This paper describes the applications of spin-valve type giant magnetoresistance sensor (GMR) for nondestructive evaluation. One is the eddy-current testing (ECT) probe which enables us to inspect micro defect and to detect micro conductors. The proposed ECT probe was applied to the inspection of bare printed circuit board and the recognition of micro solder bead for IC surface mounting package. Another is the measurement of the density of magnetic fluid injected in living body for the hyperthermia treatment. For this purpose, the needle type GMR probe was developed. The experimental results verify the possibility of the proposed system. © 2006 IEEE. 続きを見る
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論文
Somsak, T. ; Chomsuwan, K. ; Yamada, Sotoshi ; Iwahara, Masayoshi
出版情報: INTERMAG 2006 - IEEE International Magnetics Conference.  pp.3622-3624,  2006-10-01.  Institute of Electrical and Electronics Engineers (IEEE)
URL: http://hdl.handle.net/2297/11876
概要: 金沢大学環日本海域環境研究センター生体機能計測研究部門
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論文
Chomsuwan, K. ; Yamada, Sotoshi ; Iwahara, Masayoshi
出版情報: IEEE Sensors Journal.  7  pp.890-895,  2007-05-01.  IEEE
URL: http://hdl.handle.net/2297/6914
概要: 金沢大学環日本海域環境研究センター生体機能計測研究部門<br />This paper describes bare printed circuit board (PCB) inspection based on eddy-current testing (ECT) technique with high scanning speed. A high-frequency ECT probe composed of a meander coil as an exciting coil and the spin-valve giant magnetoresistance (SV-GMR) sensor was fabricated and is proposed. The ECT probe was designed based on crack inspection over flat surface, especially suitable for microdefect detection on high-density bare PCB. The ECT signal detected by the SV-GMR sensor was acquired by high-speed A/D converter for applying the signal processing based on digital technique. Harmonic analysis based on Fourier transform was used to analyze the ECT signal at fundamental frequency in order to increase inspection speed and this technique allowed the ECT probe to scan bare PCB, with high sampling frequency and with high-spatial resolution inspection. Experimental results verified the possibility and the performance of the proposed PCB inspection system based on ECT technique. © 2007 IEEE. 続きを見る