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3. The Cosmic Background Imager

Author

Padin, S., Shepherd, M. C., Cartwright, J. K., Keeney, R. G., Mason, B. S., Pearson, T. J., Readhead, A. C. S., Schaal, W. L., Sievers, J., Udomprasert, P. S., Yamasaki, J. K., Holzapfel, W. L., Carlstrom, J. E., Joy, M., Myers, S. T., and Otarola, A.

Subjects
Astrophysics
Abstract

Design and performance details are given for the Cosmic Background Imager (CBI), an interferometer array that is measuring the power spectrum of fluctuations in the cosmic microwave background radiation (CMBR) for multipoles in the range 400 < l < 3500. The CBI is located at an altitude of 5000 m in the Atacama Desert in northern Chile. It is a planar synthesis array with 13 0.9-m diameter antennas on a 6-m diameter tracking platform. Each antenna has a cooled, low-noise receiver operating in the 26-36 GHz band. Signals are cross-correlated in an analog filterbank correlator with ten 1 GHz bands. This allows spectral index measurements which can be used to distinguish CMBR signals from diffuse galactic foregrounds. A 1.2 kHz 180-deg phase switching scheme is used to reject cross-talk and low-frequency pick-up in the signal processing system. The CBI has a 3-axis mount which allows the tracking platform to be rotated about the optical axis, providing improved (u,v) coverage and a powerful discriminant against false signals generated in the receiving electronics. Rotating the tracking platform also permits polarization measurements when some of the antennas are configured for the orthogonal polarization., Comment: 14 pages. Accepted for publication in PASP. See also http://www.astro.caltech.edu/~tjp/CBI/

Published
2001
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4. Experiment Design and First Season Observations with the Degree Angular Scale Interferometer

Author

Leitch, E. M., Pryke, C., Halverson, N. W., Kovac, J., Davidson, G., LaRoque, S., Schartman, E., Yamasaki, J., Carlstrom, J. E., Holzapfel, W. L., Dragovan, M., Cartwright, J. K., Mason, B. S., Padin, S., Pearson, T. J., Shepherd, M. C., and Readhead, A. C. S.

Subjects
Astrophysics
Abstract

We describe the instrumentation, experiment design and data reduction for the first season of observations with the Degree Angular Scale Interferometer (DASI), a compact microwave interferometer designed to measure anisotropy in the Cosmic Microwave Background (CMB) on degree and sub-degree scales (l=100--900). The telescope was deployed at the Amundsen-Scott South Pole research station during the 1999--2000 austral summer and conducted observations of the CMB throughout the following austral winter. In its first season of observations, DASI has mapped CMB fluctuations in 32 fields, each 3.4 deg across, with high sensitivity., Comment: 10 pages, 6 figures, minor changes in response to referee comments

Published
2001
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5. 2022 taxonomic update of phylum Negarnaviricota (Riboviria: Orthornavirae), including the large orders Bunyavirales and Mononegavirales

Author

Kuhn, J, Adkins, S, Alkhovsky, S, Avšič-Županc, T, Ayllón, M, Bahl, J, Balkema-Buschmann, A, Ballinger, M, Bandte, M, Beer, M, Bejerman, N, Bergeron, É, Biedenkopf, N, Bigarré, L, Blair, C, Blasdell, K, Bradfute, S, Briese, T, Brown, P, Bruggmann, R, Buchholz, U, Buchmeier, M, Bukreyev, A, Burt, F, Büttner, C, Calisher, C, Candresse, T, Carson, J, Casas, I, Chandran, K, Charrel, R, Chiaki, Y, Crane, A, Crane, M, Dacheux, L, Bó, E, de la Torre, J, de Lamballerie, X, de Souza, W, de Swart, R, Dheilly, N, Di Paola, N, Di Serio, F, Dietzgen, R, Digiaro, M, Drexler, J, Duprex, W, Dürrwald, R, Easton, A, Elbeaino, T, Ergünay, K, Feng, G, Feuvrier, C, Firth, A, Fooks, A, Formenty, P, Freitas-Astúa, J, Gago-Zachert, S, García, M, García-Sastre, A, Garrison, A, Godwin, S, Gonzalez, J, de Bellocq, J, Griffiths, A, Groschup, M, Günther, S, Hammond, J, Hepojoki, J, Hierweger, M, Hongō, S, Horie, M, Horikawa, H, Hughes, H, Hume, A, Hyndman, T, Jiāng, D, Jonson, G, Junglen, S, Kadono, F, Karlin, D, Klempa, B, Klingström, J, Koch, M, Kondō, H, Koonin, E, Krásová, J, Krupovic, M, Kubota, K, Kuzmin, I, Laenen, L, Lambert, A, Lǐ, J, Li, J, Lieffrig, F, Lukashevich, I, Luo, D, Maes, P, Marklewitz, M, Marshall, S, Marzano, S, Mccauley, J, Mirazimi, A, Mohr, P, Moody, N, Morita, Y, Morrison, R, Mühlberger, E, Naidu, R, Natsuaki, T, Navarro, J, Neriya, Y, Netesov, S, Neumann, G, Nowotny, N, Ochoa-Corona, F, Palacios, G, Pallandre, L, Pallás, V, Papa, A, Paraskevopoulou, S, Parrish, C, Pauvolid-Corrêa, A, Pawęska, J, Pérez, D, Pfaff, F, Plemper, R, Postler, T, Pozet, F, Radoshitzky, S, Ramos-González, P, Rehanek, M, Resende, R, Reyes, C, Romanowski, V, Rubbenstroth, D, Rubino, L, Rumbou, A, Runstadler, J, Rupp, M, Sabanadzovic, S, Sasaya, T, Schmidt-Posthaus, H, Schwemmle, M, Seuberlich, T, Sharpe, S, Shi, M, Sironi, M, Smither, S, Song, J, Spann, K, Spengler, J, Stenglein, M, Takada, A, Tesh, R, Těšíková, J, Thornburg, N, Tischler, N, Tomitaka, Y, Tomonaga, K, Tordo, N, Tsunekawa, K, Turina, M, Tzanetakis, I, Vaira, A, van den Hoogen, B, Vanmechelen, B, Vasilakis, N, Verbeek, M, von Bargen, S, Wada, J, Wahl, V, Walker, P, Whitfield, A, Williams, J, Wolf, Y, Yamasaki, J, Yanagisawa, H, Ye, G, Zhang, Y, Økland, A, Kuhn JH, Adkins S, Alkhovsky SV, Avšič-Županc T, Ayllón MA, Bahl J, Balkema-Buschmann A, Ballinger MJ, Bandte M, Beer M, Bejerman N, Bergeron É, Biedenkopf N, Bigarré L, Blair CD, Blasdell KR, Bradfute SB, Briese T, Brown PA, Bruggmann R, Buchholz UJ, Buchmeier MJ, Bukreyev A, Burt F, Büttner C, Calisher CH, Candresse T, Carson J, Casas I, Chandran K, Charrel RN, Chiaki Y, Crane A, Crane M, Dacheux L, Bó ED, de la Torre JC, de Lamballerie X, de Souza WM, de Swart RL, Dheilly NM, Di Paola N, Di Serio F, Dietzgen RG, Digiaro M, Drexler JF, Duprex WP, Dürrwald R, Easton AJ, Elbeaino T, Ergünay K, Feng G, Feuvrier C, Firth AE, Fooks AR, Formenty PBH, Freitas-Astúa J, Gago-Zachert S, García ML, García-Sastre A, Garrison AR, Godwin SE, Gonzalez JJ, de Bellocq JG, Griffiths A, Groschup MH, Günther S, Hammond J, Hepojoki J, Hierweger MM, Hongō S, Horie M, Horikawa H, Hughes HR, Hume AJ, Hyndman TH, Jiāng D, Jonson GB, Junglen S, Kadono F, Karlin DG, Klempa B, Klingström J, Koch MC, Kondō H, Koonin EV, Krásová J, Krupovic M, Kubota K, Kuzmin IV, Laenen L, Lambert AJ, Lǐ J, Li JM, Lieffrig F, Lukashevich IS, Luo D, Maes P, Marklewitz M, Marshall SH, Marzano SL, McCauley JW, Mirazimi A, Mohr PG, Moody NJG, Morita Y, Morrison RN, Mühlberger E, Naidu R, Natsuaki T, Navarro JA, Neriya Y, Netesov SV, Neumann G, Nowotny N, Ochoa-Corona FM, Palacios G, Pallandre L, Pallás V, Papa A, Paraskevopoulou S, Parrish CR, Pauvolid-Corrêa A, Pawęska JT, Pérez DR, Pfaff F, Plemper RK, Postler TS, Pozet F, Radoshitzky SR, Ramos-González PL, Rehanek M, Resende RO, Reyes CA, Romanowski V, Rubbenstroth D, Rubino L, Rumbou A, Runstadler JA, Rupp M, Sabanadzovic S, Sasaya T, Schmidt-Posthaus H, Schwemmle M, Seuberlich T, Sharpe SR, Shi M, Sironi M, Smither S, Song JW, Spann KM, Spengler JR, Stenglein MD, Takada A, Tesh RB, Těšíková J, Thornburg NJ, Tischler ND, Tomitaka Y, Tomonaga K, Tordo N, Tsunekawa K, Turina M, Tzanetakis IE, Vaira AM, van den Hoogen B, Vanmechelen B, Vasilakis N, Verbeek M, von Bargen S, Wada J, Wahl V, Walker PJ, Whitfield AE, Williams JV, Wolf YI, Yamasaki J, Yanagisawa H, Ye G, Zhang YZ, Økland AL., Kuhn, J, Adkins, S, Alkhovsky, S, Avšič-Županc, T, Ayllón, M, Bahl, J, Balkema-Buschmann, A, Ballinger, M, Bandte, M, Beer, M, Bejerman, N, Bergeron, É, Biedenkopf, N, Bigarré, L, Blair, C, Blasdell, K, Bradfute, S, Briese, T, Brown, P, Bruggmann, R, Buchholz, U, Buchmeier, M, Bukreyev, A, Burt, F, Büttner, C, Calisher, C, Candresse, T, Carson, J, Casas, I, Chandran, K, Charrel, R, Chiaki, Y, Crane, A, Crane, M, Dacheux, L, Bó, E, de la Torre, J, de Lamballerie, X, de Souza, W, de Swart, R, Dheilly, N, Di Paola, N, Di Serio, F, Dietzgen, R, Digiaro, M, Drexler, J, Duprex, W, Dürrwald, R, Easton, A, Elbeaino, T, Ergünay, K, Feng, G, Feuvrier, C, Firth, A, Fooks, A, Formenty, P, Freitas-Astúa, J, Gago-Zachert, S, García, M, García-Sastre, A, Garrison, A, Godwin, S, Gonzalez, J, de Bellocq, J, Griffiths, A, Groschup, M, Günther, S, Hammond, J, Hepojoki, J, Hierweger, M, Hongō, S, Horie, M, Horikawa, H, Hughes, H, Hume, A, Hyndman, T, Jiāng, D, Jonson, G, Junglen, S, Kadono, F, Karlin, D, Klempa, B, Klingström, J, Koch, M, Kondō, H, Koonin, E, Krásová, J, Krupovic, M, Kubota, K, Kuzmin, I, Laenen, L, Lambert, A, Lǐ, J, Li, J, Lieffrig, F, Lukashevich, I, Luo, D, Maes, P, Marklewitz, M, Marshall, S, Marzano, S, Mccauley, J, Mirazimi, A, Mohr, P, Moody, N, Morita, Y, Morrison, R, Mühlberger, E, Naidu, R, Natsuaki, T, Navarro, J, Neriya, Y, Netesov, S, Neumann, G, Nowotny, N, Ochoa-Corona, F, Palacios, G, Pallandre, L, Pallás, V, Papa, A, Paraskevopoulou, S, Parrish, C, Pauvolid-Corrêa, A, Pawęska, J, Pérez, D, Pfaff, F, Plemper, R, Postler, T, Pozet, F, Radoshitzky, S, Ramos-González, P, Rehanek, M, Resende, R, Reyes, C, Romanowski, V, Rubbenstroth, D, Rubino, L, Rumbou, A, Runstadler, J, Rupp, M, Sabanadzovic, S, Sasaya, T, Schmidt-Posthaus, H, Schwemmle, M, Seuberlich, T, Sharpe, S, Shi, M, Sironi, M, Smither, S, Song, J, Spann, K, Spengler, J, Stenglein, M, Takada, A, Tesh, R, Těšíková, J, Thornburg, N, Tischler, N, Tomitaka, Y, Tomonaga, K, Tordo, N, Tsunekawa, K, Turina, M, Tzanetakis, I, Vaira, A, van den Hoogen, B, Vanmechelen, B, Vasilakis, N, Verbeek, M, von Bargen, S, Wada, J, Wahl, V, Walker, P, Whitfield, A, Williams, J, Wolf, Y, Yamasaki, J, Yanagisawa, H, Ye, G, Zhang, Y, Økland, A, Kuhn JH, Adkins S, Alkhovsky SV, Avšič-Županc T, Ayllón MA, Bahl J, Balkema-Buschmann A, Ballinger MJ, Bandte M, Beer M, Bejerman N, Bergeron É, Biedenkopf N, Bigarré L, Blair CD, Blasdell KR, Bradfute SB, Briese T, Brown PA, Bruggmann R, Buchholz UJ, Buchmeier MJ, Bukreyev A, Burt F, Büttner C, Calisher CH, Candresse T, Carson J, Casas I, Chandran K, Charrel RN, Chiaki Y, Crane A, Crane M, Dacheux L, Bó ED, de la Torre JC, de Lamballerie X, de Souza WM, de Swart RL, Dheilly NM, Di Paola N, Di Serio F, Dietzgen RG, Digiaro M, Drexler JF, Duprex WP, Dürrwald R, Easton AJ, Elbeaino T, Ergünay K, Feng G, Feuvrier C, Firth AE, Fooks AR, Formenty PBH, Freitas-Astúa J, Gago-Zachert S, García ML, García-Sastre A, Garrison AR, Godwin SE, Gonzalez JJ, de Bellocq JG, Griffiths A, Groschup MH, Günther S, Hammond J, Hepojoki J, Hierweger MM, Hongō S, Horie M, Horikawa H, Hughes HR, Hume AJ, Hyndman TH, Jiāng D, Jonson GB, Junglen S, Kadono F, Karlin DG, Klempa B, Klingström J, Koch MC, Kondō H, Koonin EV, Krásová J, Krupovic M, Kubota K, Kuzmin IV, Laenen L, Lambert AJ, Lǐ J, Li JM, Lieffrig F, Lukashevich IS, Luo D, Maes P, Marklewitz M, Marshall SH, Marzano SL, McCauley JW, Mirazimi A, Mohr PG, Moody NJG, Morita Y, Morrison RN, Mühlberger E, Naidu R, Natsuaki T, Navarro JA, Neriya Y, Netesov SV, Neumann G, Nowotny N, Ochoa-Corona FM, Palacios G, Pallandre L, Pallás V, Papa A, Paraskevopoulou S, Parrish CR, Pauvolid-Corrêa A, Pawęska JT, Pérez DR, Pfaff F, Plemper RK, Postler TS, Pozet F, Radoshitzky SR, Ramos-González PL, Rehanek M, Resende RO, Reyes CA, Romanowski V, Rubbenstroth D, Rubino L, Rumbou A, Runstadler JA, Rupp M, Sabanadzovic S, Sasaya T, Schmidt-Posthaus H, Schwemmle M, Seuberlich T, Sharpe SR, Shi M, Sironi M, Smither S, Song JW, Spann KM, Spengler JR, Stenglein MD, Takada A, Tesh RB, Těšíková J, Thornburg NJ, Tischler ND, Tomitaka Y, Tomonaga K, Tordo N, Tsunekawa K, Turina M, Tzanetakis IE, Vaira AM, van den Hoogen B, Vanmechelen B, Vasilakis N, Verbeek M, von Bargen S, Wada J, Wahl V, Walker PJ, Whitfield AE, Williams JV, Wolf YI, Yamasaki J, Yanagisawa H, Ye G, Zhang YZ, and Økland AL.

Abstract

In March 2022, following the annual International Committee on Taxonomy of Viruses (ICTV) ratification vote on newly proposed taxa, the phylum Negarnaviricota was amended and emended. The phylum was expanded by two new families (bunyaviral Discoviridae and Tulasviridae), 41 new genera, and 98 new species. Three hundred forty-nine species were renamed and/or moved. The accidentally misspelled names of seven species were corrected. This article presents the updated taxonomy of Negarnaviricota as now accepted by the ICTV.

Published
2022

10. The Cosmic Background Imager

Author

Padin, S., Shepherd, M. C., Cartwright, J. K., Keeney, R. G., Mason, B. S., Pearson, T. J., Readhead, A. C. S., Schaal, W. A., Sievers, J., Udomprasert, P. S., Yamasaki, J. K., Holzapfel, W. L., Carlstrom, J. E., Joy, M., Myers, S. T., and Otarola, A.

Published
2002
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11. Factors Associated with Regular Zumba Practice to Reduce Prevalence of Non-communicable Diseases: A Population-Based Approach in Cebu and Mactan, the Philippines

Author

Sakisaka K, Solute Ng, Delos Santos Njv, Mission Pa, Yamasaki J, Palaca Jv, and Pacalioga Rpo

Subjects
Geography, allergology, Environmental health, Physical activity, Population based
Abstract

The prevalence of overweight/obesity in the adult population in the Philippines has doubled in the past 20 years. Zumba exercise has recently been implemented throughout the Philippines. However, there is scarce information on the effects of Zumba on obesity and Zumba participants’ characteristics in the Philippines. This study described the current practice of Zumba in the Philippines, along with the practitioners’ characteristics, and identified factors associated with Zumba participation. In this observational, cross-sectional study, a structured questionnaire was used to survey 10 Zumba locations in September 2019. Anthropometric measurements of participants were assessed. Respondents included 171 women (88.6%) and 22 men (11.4%), with a mean (±SD) age of 44.1 (± 8.9) years. All respondents answered that Zumba was enjoyable, and some answered “very enjoyable.” Determinants of frequent participation were as follows: being older than the mean age of participants, starting Zumba to enjoy dancing, starting Zumba not to lose weight, shopping mall location, and participation fee required. “To enjoy dance” being a motivation for Zumba practice was identified as a determinant of frequent participation, rather than “to lose weight.” The element of “enjoyable” may strongly influence continuation and frequent participation of Zumba exercise in the Philippines.

Published
2021
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15. Effect of surface microstructure on magnetization process in [Fe.sub.80.5][Cu.sub.1.5][Si.sub.4][B.sub.14]nanocrystalline alloys

Author

Ohta, M., Yoshizawa, Y., Takezawa, M., and Yamasaki, J.

Subjects
Copper alloys -- Structure, Copper alloys -- Magnetic properties, Iron alloys -- Structure, Iron alloys -- Magnetic properties, Magnetic materials -- Mechanical properties, Magnetization -- Analysis, Silicon -- Magnetic properties, Boron -- Magnetic properties, Business, Electronics, Electronics and electrical industries
Published
2010

18. Review of fabrication and characterization of Nd-Fe-B thick films for magnetic micromachines

Author

Nakano, M., Sato, S., Yamashita, F., Honda, T., Yamasaki, J., Ishiyama, K., Itakura, M., Fidler, J., Yanai, T., and Fukunaga, H.

Subjects
Neodymium -- Magnetic properties, Iron compounds -- Magnetic properties, Ablation (Vaporization technology) -- Methods, Magnetic devices -- Design and construction, Business, Electronics, Electronics and electrical industries
Abstract

Isotropic Nd-Fe--B thick film magnets were prepared by a high-speed pulsed laser deposition method followed by a post annealing. The deposition rate of 90 [micro]m/h could be successfully achieved, and a pulse annealing was adopted as the post annealing process in order to enhance coercivity. Use of a substrate heating system under the high deposition rate enabled us to obtain anisotropic thick films with [(BH).sub.max] of approximately 120 kJ/[m.sup.3], which show the potential for an improvement in the properties of the micromachines. Novel micromachines comprising the isotropic films were introduced. Index Terms--Laser ablation, micromachines, micromotors, thick film devices.

Published
2007

24. Annual Nationwide Eco-Efficiency Assessment of Japanese Municipalities Based on Environmental Impact and Gross Regional Product

Author

Itsubo N, Ikaga T, and Yamasaki J

Subjects
environmental_sciences, Natural resource economics, Local government, Gross Regional Product, Environmental impact assessment, Business, Eco-efficiency, Environmental accounting
Abstract

It is important for enterprises to decide their environmental policies after carefully examining their future paths based on the relationship between the environment and the economy. This study focused on Japanese minimum administrative divisions (municipalities) and attempted to quantify the annual environmental efficiency of production activities within each division according to the theory of life-cycle impact assessment (LCIA). This study leverages the assessment theory LIME2, which is an endpoint-type LCIA method developed in 2010 that integrates environmental loads for certain impact categories, such as global warming and land use into a simple indicator by monetary unit. First, annual environmental impact assessments were conducted for all Japanese municipalities based on statistical information that was reliable, verifiable, and comparable. Next, the environmental efficiency of productivity for each division was conceptualized by dividing the gross domestic product by the environmental damage amounts as calculated above. Assessment results for each municipality were placed on a map of Japan in order to visualize the regionality of each indicator. The findings revealed in this study will aid public administrators in their decision-making process with respect to environmental policies.

Published
2019
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25. Structural Stability of Iodide Perovskite: A Combined Cluster Expansion Method and First-Principles Study

Author

Graduate School of Life Science and Systems Engineering, Kyushu Institute of Technology, Yamamoto, K., Iikubo, S., Yamasaki, J., Ogomi, Y., Hayase, S., Graduate School of Life Science and Systems Engineering, Kyushu Institute of Technology, Yamamoto, K., Iikubo, S., Yamasaki, J., Ogomi, Y., and Hayase, S.

Abstract

type:Journal Article, To aid the development of Pb-free perovskite solar cells, the stability of the iodide perovskite structure ABI3 has been investigated by first-principles calculations, Bader charge analysis, and the cluster expansion method. At the A sites, methylammonium (MA, CH3NH3+), formamidinium (FA, CH(NH2)2+), and Cs+ were modeled, while at the B sites, one or two elements from Pb, Sn, Ge, In, Ga, Bi, and Sr were examined. For the partially substituted system A(B,B′)I3, we found that the stability strongly depends on the identity of the A-site cation. For example, Cs(B,B′)I3 structures are stabilized by a mixture of divalent cations, such as Pb, Sn, and Ge, at the B site. Concerning the stabilization mechanisms, Coulomb energy gain seems to be the origin of the structural stability in A = Cs structures. From our results, Cs(B,B′)I3, where the B site is occupied by divalent cations, are possible candidates for high stability, lead-free solar cell materials.

Published
2019

28. Analysis of steplike change of impedance for thin-like giant magnetoimpedance element with inclined stripe magnetic domain based on magnetic energy

Author

Nakai, T., Ishiyama, K., and Yamasaki, J.

Subjects
Dielectric films -- Magnetic properties, Thin films -- Magnetic properties, Magnetoresistance -- Research, Cobalt alloys -- Magnetic properties, Niobium alloys -- Magnetic properties, Zirconium -- Magnetic properties, Physics
Abstract

The steplike impedance change for thin-film giant magnetoimpedance (GMI) element is analyzed. The analysis has shown that the magnetic energy of the two phases have intersected each other in a certain external magnetic field, indicating that the basis of steplike GMI of thin-film element is disclosed as a structural change of magnetic domain based on magnetic energy.

Published
2007

30. Effect of strain by mechanical punching on nonoriented Si-Fe electrical sheets for a nine-slot motor core

Author

Takezawa, M., Kitajima, K., Morimoto, Y., Yamasaki, J., and Kaido, C.

Subjects
Electromagnetism -- Research, Magnetization -- Research, Direct current electric motors -- Research, Business, Electronics, Electronics and electrical industries
Abstract

Domain observation has been done to investigate the effect of strain due to a punching process on the magnetization process of a nine-slot core for 12-pole small brushless dc motor by using the Kerr microscopy technique. Stripe domain structures oriented to a transverse direction are observed at the edge of a tooth of the core without stress relief annealing. Due to the domain configuration, permeability near the punched edge of the motor core is reduced. A stress relief annealing at 700 [degrees]C for 2 h can relive the punching stress. Index Terms--Magnetic domain observation, nonoriented Si-Fe electrical sheet, punching process, stress relief annealing.

Published
2006

32. Micromagnetic study of domain wall-pinning characteristics with step-like thickness change in thin film

Author

Asada, H., Hyodo, Y., Yamasaki, J., Takezawa, M., and Koyanagi, T.

Subjects
Thick films -- Research, Electromagnetism -- Research, Business, Electronics, Electronics and electrical industries
Abstract

The pinning characteristics of a domain wall with a step-like thickness change along the wall is investigated in 0.15- to 0.5-[micro]m-thick films with an in-plane anisotropy using micromagnetic simulation based on the Landau-Lifshitz-Gilbert equation. The asymmetric Bloch wall having the structure in which the magnetostatic coupling develops between spins near the step when the wall is pinned shows the bi-directional pinning effect for magnetic fields applied along the magnetic domain. The wall energy of the pinned wall decreases with increasing step depth due to the largely decrease of the exchange energy component. The depinning field for the negative applied fields which drive the wall in the direction of the nongrooved region (thick film region) is considerably larger than that for the positive ones which drive the wail in the direction of the grooved region (thin film region). The depinning fields for both the positive and negative applied fields increase with decreasing film thickness. Index Terms--Domain wall pinning, groove, micromagnetic simulation, thickness variation.

Published
2004

33. Effect of grain size on domain structure of thin nonoriented Si-Fe electrical sheets

Author

Takezawa, M., Wada, Y., Yamasaki, J., Honda, T., and Kaido, C.

Subjects
Magnetic materials -- Research, Business, Electronics, Electronics and electrical industries
Abstract

Domain configuration of the nonoriented Si-Fe electrical sheets with different grain size was observed decreasing their sheet thickness by using the Kerr effect. It was found that the nonoriented sheet needs multiple grains in the sheet thickness direction to eliminate the normal magnetization component in the flux closing structure causing excessive eddy current loss. Index Terms--Anomaly factor, domain structure, grain size, nonoriented Si-Fe electrical sheets.

Published
2003

35. Fabrication and testing of a small pump composed of a magnet and an elastic plate

Author

Honda, T., Yamasaki, J., and Arai, K.I.

Subjects
Electromagnetic pumps -- Design and construction, Magnets, Permanent -- Usage, Torque -- Research, Business, Electronics, Electronics and electrical industries
Abstract

A new type of micro-pump using an angular movement of an elastic plate is proposed. The moving part of the pump consists of a small permanent magnet attached to an elastic plate. Iran alternating magnetic field is applied, the magnet vibrates angularly due to magnetic torque and then the polyimide film causes a unidirectional movement of fluid. A cm-size pump based on this mechanism has been constructed and tested. The maximum flow rate of 750 ml/min and the maximum pressure of approximately 4.2 kPa were achieved when ethyl alcohol was used as a working fluid. Index Terms - angular movement, micro-pump, permanent magnet, magnetic torque.

Published
1998

36. Effect of stress on the bamboo domains and magnetization process of CoSiB amorphous wire

Author

Nderu, J.N., Takajo, M., Yamasaki, J., and Humphrey, F.B.

Subjects
Domain structure -- Research, Stress concentration -- Research, Electrical wire -- Research, Business, Electronics, Electronics and electrical industries
Abstract

In this work we have studied the behavior of the bamboo domains under stress ([Sigma]), tension (+ [Sigma]) as well as compression (-[Sigma]), with the aim of making the domain model of the negatively magnetostrictive (-[[Lambda].sub.s]) CoSiB wire clear. It is observed that the growth of the surface bamboo domains due to [Sigma] has directivity depending on the orientation of the underlying core domain. In one orientation the black bamboo domain grows, while in the opposite orientation the white domain grows. From the stress behavior of the bamboo domains we have concluded that the domain model of -[[Lambda].sub.s], wire consists of two spiral domains of opposite rotation and proposed a new model. Index Terms - bamboo domains, domain model, spiral domains of opposite rotation, stress

Published
1998

37. Fabrication of a micromotor driven by electromagnetic vibration

Author

Honda, T. and Yamasaki, J.

Subjects
Electromagnetism -- Observations, Friction -- Usage, Physics
Abstract

A new electromagnetic rotary mechanism based on a friction drive has been proposed. The electromagnetic vibration on a permanent magnet was converted to rotary movement via a frictional force, and a trial motor, consisting of a magnet rotor, inclined legs and an excitation coil, was developed and successfully operated. A no-load revolution speed of up to 400 rpm and reversible rotation were obtained.

Published
1998

38. Magnetization process in hard axis of Fe-Co based amorphous ribbons with induced anisotropy

Author

Yamasaki, J., Chuman, T., Yagi, M., and Yamaoka, M.

Subjects
Magnetization -- Research, Amorphous substances -- Magnetic properties, Anisotropy -- Research, Business, Electronics, Electronics and electrical industries
Abstract

Magnetization process of amorphous ribbons in the hard axis of magnetization was investigated by observation of magnetic domains having the easy axis of induced anisotropy in the transverse direction. It was found that a field applied in the longitudinal direction caused wall motion as well as magnetization rotation through re-arrangement of energy balance between magnetostatic and wall energies. Re-annealing of ribbons in a remanent state without a magnetic field caused domain wall pinning that restrained wall motion and improved the magnetic properties at high frequency markedly.

Published
1997

41. Annealing effects on a high-k lanthanum oxide film on Si (001) analyzed by aberration-corrected transmission electron microscopy/scanning transmission electron microscopy and electron energy loss spectroscopy.

Author

Inamoto, S., Yamasaki, J., Okunishi, E., Kakushima, K., Iwai, H., and Tanaka, N.

Subjects
*LANTHANUM compounds, *THIN films, *ELECTRON beams, *SCANNING transmission electron microscopy, *ANNEALING of metals
Abstract

The annealing behavior of a lanthanum oxide thin film deposited on a silicon (001) substrate by electron-beam evaporation has been studied by aberration-corrected transmission electron microscopy (TEM), scanning TEM (STEM), and electron energy loss spectroscopy (EELS). We have developed a procedure for the precise measurement of thickness and interfacial roughness by taking advantage of features of aberration correction combined with the statistics of fluctuating crystalline edge positions. The results of the measurements and quantitative elemental analyses by STEM-EELS have revealed atomic diffusion and reactions during deposition and postdeposition annealing (PDA) at 300 and 500 °C. The channel mobility could be limited by Coulomb scattering before PDA, and by remote roughness scattering and remote phonon scattering after PDA at 500 °C. When we consider the large leakage current caused by oxygen defects in the as-deposited sample and the large equivalent oxide thickness of the thick Si-rich layer in the 500 °C-PDA sample, the gate properties of the 300 °C-PDA sample should be better than those of other samples, as shown by electrical measurements. [ABSTRACT FROM AUTHOR]

Published
2010
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42. Dependence of magnetic properties of (Fe50Co50)78Si7B15 amorphous wire on the diameter

Author

Nderu, J.N., Shinokawa, Y., Yamasaki, J., Humphrey, F.B., and Ogasawara, L.

Subjects
Wire -- Evaluation, Magnetic materials -- Evaluation, Domain structure -- Analysis, Business, Electronics, Electronics and electrical industries
Abstract

The dependence of the magnetic properties of amorphous wire on the diameter have been investigated. The anisotropy constant, hence the internal stress, of the wire increases with the wire diameter. The size of the pinned reverse domain at the wire end increases with the wire diameter. Domain observation shows that irrespective of the change in the wire diameter, the domain structure basically consists of chevron domain layer sandwiched between the surface maze domain and the inner core domain.

Published
1996

43. Large Barkhausen discontinuity of Co-Fe-Si-B amorphous films sputtered on polymer substrate

Author

Yano, N., Furukawa, S., Oka, K., Ogasawara, I., Yamasaki, J., and Humphrey, F.B.

Subjects
Thin films -- Magnetic properties, Magnetic materials -- Evaluation, Microstructure -- Analysis, Domain structure -- Analysis, Business, Electronics, Electronics and electrical industries
Abstract

Co-Fe-Si-B films have been prepared using a roll coater and DC magnetron sputtering system onto a polyethylene terephthalate substrate. This thin film exhibited an excellent uniaxial anisotropy introduced by an asymmetric thermal shrinkage of the substrate. Reversal with a single large Barkhausen pulse has been observed in a thin film structure 1mm by 50mm by 0.65 [[micro]meter]. Closure domains have been clearly identified at the film ends. The threshold for the reversal is the coercive force. The reason for reversal with a single Barkhausen jump is that the long narrow film geometry has essentially zero demagnetizing field over most of the film. Once the walls start to move through the center portion of the film, there is nothing to stop them so the reversal proceeds with a single large Barkhausen pulse.

Published
1996

45. Uniaxial magnetic FeC thin films sputtered onto polymer substrates

Author

Oka, K., Yano, N., Furukawa, S., Ogasawara, I., Yamasaki, J., and Humphrey, F.B.

Subjects
Thin films -- Production processes, Magnetic materials -- Production processes, Iron alloys -- Production processes, Business, Electronics, Electronics and electrical industries
Published
1995

48. Domain observation technique for Nd-Fe-B magnet in high magnetic field by image processing using liquid crystal modulator

Author

Kyushu Inst Technol, Dept Appl Sci Integrated Syst Engn, Takezawa, M, Shimada, T, Kondo, S, Mimura, S, Morimoto, Y, Hidaka, T, Yamasaki, J, Kyushu Inst Technol, Dept Appl Sci Integrated Syst Engn, Takezawa, M, Shimada, T, Kondo, S, Mimura, S, Morimoto, Y, Hidaka, T, and Yamasaki, J

Abstract

type:Journal Article, A different domain observation technique by modulation of a polarizing plane has been developed for Nd-Fe-B sintered magnets. A liquid crystal element inserted in a longitudinal Kerr microscope is used as an optical modulator to acquire a reference image needed to enhance Kerr contrast by image processing. Domain images of the Nd-Fe-B magnet can be clearly observed by this technique in a high magnetic field up to 4.4 kOe. It was found that polishing of the sintered magnet reduced its coercive force. (c) 2007 American Institute of Physics., source:http://dx.doi.org/10.1063/1.2712961, source:http://www.aip.org

Published
2017

49. Magnetostriction Measurement of Amorphous Wires by Means of Small-Angle Magnetization Rotation

Author

Department of Electrical Engineering, Kyushu Institute of Technology, Tobata, Kitakyushu 804, Japan, Yamasaki, J, Ohkubo, Y, Humphrey, FB, Department of Electrical Engineering, Kyushu Institute of Technology, Tobata, Kitakyushu 804, Japan, Yamasaki, J, Ohkubo, Y, and Humphrey, FB

Abstract

type:Journal Article, The small-angle magnetization rotation method has been shown to be applicable for measuring the saturation magnetostriction of amorphous wires by using the circumferential field generated by an ac current through the wire. The method was used to measure compositional variation of magnetostriction of Fe-Co based amorphous wires. A saturation magnetostriction s of 32.9×10−6 and −2.6×10−6 was found for Fe and Co based wires, respectively. The compositional variation of the saturation magnetostriction, s, for (Fe1−xCox)75Si10B15 amorphous wires (X=0–0.8) decreases with increasing cobalt content and crosses zero around X=0.95 as in amorphous ribbons. The maximum experimental error of measurement was estimated to be about 5%., source:http://www.aip.org, source:https://doi.org/10.1063/1.345849

Published
2017

50. Dynamic and wide field domain observation of amorphous ribbons with longitudinal Kerr effect microscopy

Author

Kyushu Inst Technol, Dept Appl Sci Integrated Syst Engn, Takezawa, M, Kitajima, K, Morimoto, Y, Yamasaki, J, Kyushu Inst Technol, Dept Appl Sci Integrated Syst Engn, Takezawa, M, Kitajima, K, Morimoto, Y, and Yamasaki, J

Abstract

type:Journal Article, Wide field and dynamic domain observation has been done to investigate re-entrant characteristics of amorphous ribbons by adjusting a light path of a Kerr microscope and by triggering a CCD camera. It has been shown that a wide field of 2.6 mm x 2.3 mm with less image distortion was achieved by critical modulation of the light path between an objective lens and samples. The remagnetization process of amorphous ribbons with pinned walls starts with wall depinning and reverse domain nucleation. (c) 2005 American Institute of Physics., source:http://dx.doi.org/10.1063/1.1853205, source:http://www.aip.org

Published
2017

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