179,363 research outputs found
Light-matter interactions with Flying Doughnuts
No full textThe field of toroidal electrodynamics has gained attention following the detection of toroidal dipole excitations in metamaterials in 2010. Distinct from electric and magnetic dipoles, a toroidal dipole is a localised electromagnetic excitation that corresponds to currents flowing on the surface of a torus. The electromagnetic radiation from toroidal dipole excitations can destructively interfere with the radiation from other modes of excitation, providing a new mechanism of induced transparency and scattering suppression. Toroidal electrodynamics expands with the observation of toroidal light pulses, also known as Flying Doughnuts (FD), which propagate in free space at the speed of light. FDs are solutions to Maxwell’s equations introduced by Hellwarth and Nouchi in 1996, which possess toroidal topology and exist only as short bursts of electromagnetic energy. However, it is little known about how these toroidal pulses interact with matter. This thesis reports on the interaction of toroidal light pulses with matter, focusing on toroidal excitations and non-radiating modes.I have numerically demonstrated supertoroidal anapoles, which are non-radiating charge current configurations that involve supertoroidal currents. Supertoroidal currents are fractal current configurations where each iteration replaces the previous one with a toroidal current loop, accompanied by a toroidal solenoidal current forming the smallest loop. Unlike conventional anapoles formed by the destructive interference of electric and toroidal dipoles, supertoroidal anapoles consist of the interference of a toroidal dipole, the first-order mean square radius of the toroidal dipole, and an electric dipole. I also observed (numerically) the higher-order anapoles formed from quadrupoles and octupoles of electric and toroidal type. I show numerically that under illumination with an FD pulse, scattering from a dielectric torus is substantially suppressed by supertoroidal anapoles by more than 72%. Further, I studied supertoroidal anapoles’dependence on the torus’s geometric parameters. I discovered that a dielectric torus with the largest major radius R and the smallest minor radius r is the best strategy to support supertoroidal anapoles, where R ≫ r and R+r < λ. Moreover, I show that, in contrast to plane wave illumination, FD illumination suppresses scattering by an order of magnitude due to supertoroidal anapoles.I demonstrated that by carefully tuning the geometric parameters of a dielectric disc, it is possible to engineer anapole modes (scattering suppression) over a broad bandwidth of 315nm within the wavelength range from 665nm to 980nm with the maximum suppression at 780nm, when transverse magnetic (TM) FD is an illuminating source and a disc-shaped particle is the scatterer. Further, I show that the disc radius defines the anapole excitation wavelength, and the disc height defines the bandwidth of the anapole; the taller the disc (h < λ), the broader the anapole. Additionally, I show the electric and toroidal dipoles and the anapole mode in the transient regime. I also demonstrate that even though the duration of the incident pulse is ≈ 4 fs, the excitations take up to 15 fs to dissipate their energy through electromagnetic radiation. Further, I investigated the effect of material loss on scattering suppression and observed broadly similar behaviour to lossless material, supporting broad and strong anapole modes. Moreover, unlike plane wave illumination, I report that FD illumination suppresses scattering by an order of magnitude due to the conventional anapole modes.I also investigated the interaction of FD with films and curved interfaces. I demonstrated that the reflection of transverse electric (TE) FD on dielectric film and plasmonic films is 20% and 15% stronger, respectively, compared to TM FD illumination. Moreover, the multipole expansion of displacement current within a high-index dispersive film reveals that the scattering is mediated by the combination of electric and toroidal dipoles (however, their contributions cannot be distinguished with the exact multipole expressions). Investigating FD interactions with curved interfaces shows that the radial spectra distribution of FD does not change upon reflection from the curved interface, which ensures that FD survives after interacting with a curved interface. The findings of FD interactions with curved interfaces are crucial for the experimental realisation of FD-matter interaction, as such experiments involve curved optical components such as parabolic mirrors for the tight focusing of FD.The findings outlined in this thesis contribute to the expanding field of toroidal electrodynamics, firmly establishing its potential for diverse applications, including sensing and spectroscopy using toroidal light sources, anapole nanolasers, anapole-assisted absorption engineering applications, and beyond
Appropriate Similarity Measures for Author Cocitation Analysis
No full textWe provide a number of new insights into the methodological discussion about author cocitation analysis. We first argue that the use of the Pearson correlation for measuring the similarity between authors’ cocitation profiles is not very satisfactory. We then discuss what kind of similarity measures may be used as an alternative to the Pearson correlation. We consider three similarity measures in particular. One is the well-known cosine. The other two similarity measures have not been used before in the bibliometric literature. Finally, we show by means of an example that our findings have a high practical relevance.information science;Pearson correlation;cosine;similarity measure;author cocitation analysis
"Closing the R&D Gap, Evaluating the Sources of R&D Spending"
No full textBoth spending and tax policies have been implemented in the United States with the goal of stimulating private sector research and development (R&D). Karier questions whether current R&D policy, especially the research and experimentation tax credit, can contribute to closing the gap between nondefense expenditures on R&D in the United States and such expenditures in other countries, such as Japan and Germany. He also explores possible changes to our current R&D policy to make it more effective.
Going Beyond Counting First Authors in Author Co-citation Analysis
No full textThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
Ça da Türk resmi ve Burhan Temel
No full textÇa da Türk Resminde Burhan Temel ba l kl bu tez çal mas nda Burhan
Temel in ya am , sanatç kimli i, e itimci yönü ve eserleri incelenmi tir. Türk Resmi
nde kimlik aray , öze yönelme hareketi, biçim ve konu sorunu olarak ele al nm t r.
Ça da Türk Resim Sanat gruplar halinde incelenmi ve Burhan Temel in sanat ,
eserleriyle Türk Resim Sanat na kazand rd klar ara t r lm t r.
Bu ba lamda tez çal mas n n birinci bölümünde Burhan Temel in sanat na
zemin haz rlayan; Ça da Türk Resmi nde Bat etkisi, Cumhuriyet sonras geli meler
ve Ça da Türk Resmi nde grupla ma e ilimleri incelenmi tir. kinci bölümde ise
Burhan Temel in sanat hayat ve eserleri biçim içerik ba lam nda de erlendirilmi tir.
Çal man n Üçüncü bölümünde II. Dünya Sava sonras Türkiye de sanat ortam dö nemin politik ko ullar ba lam nda incelenmi tir. Ayr ca bu bölümde Burhan Te mel in sanat ya am n derinden etkileyen Onlar Grubu ile ilgili bilgi de yer almaktad r.
Çal man n Dördüncü bölümü ise tez çal mas için en özgün bölümdür. Bu bölümde
Burhan Temel in ya am ve eserleri incelenerek literatüre kazand r lm t r
Letter from R. R. Zellick, Assistant Trust Officer, Anglo California National Bank of San Francisco, to Joseph R. Goodman, October 2, 1942
No full textLetter from R. R. Zellick, Assistant Trust Officer at The Anglo California National Bank of San Francisco, to Joseph R. Goodman, regarding property owned by Dave Tatsuno. Zellick mentions a dispute between current tenants and Tatsuno, and that Tatsuno has asked Goodman to help locate trustworthy tenants.Personal correspondence, organizational records, government documents, publications, and other papers created or collected by Joseph R. Goodman documenting the forced removal and incarceration of Japanese Americans during World War II, as well as organized resistance to incarceration. Included in the collection are records of the Japanese Young Men's Christian Association and the Japanese American Citizens' League in San Francisco, including papers of the Japanese YMCA's executive secretary Lincoln Kanai; Sakai family papers; Goodman's correspondence to and from Japanese American incarcerees, organizations opposing forced removal and incarceration of Japanese Americans, the War Relocation Authority, and others; publications, photographs, and ephemera from the Topaz Relocation Center, where Goodman taught high school; War Relocation Authority records and publications; and newspaper clippings, pamphlets, and reports about forced removal and incarceration created by various government, religious, and civic organizations, in California and nationwide
Dispelling the Myths Behind First-author Citation Counts
No full textWe conducted a full-scale evaluative citation analysis study of scholars in the XML research field to explore just how different from each other author rankings resulting from different citation counting methods actually are, and to demonstrate the capability of emerging data and tools on the Web in supporting more realistic citation counting methods. Our results contest some common arguments for the continued
use of first-author citation counts in the evaluation of scholars, such as high correlations between author rankings by first-author citation counts and other citation
counting methods, and high costs of using more realistic citation counting methods that are not well-supported by the ISI databases. It is argued that increasingly available digital full text research papers make it possible for citation analysis studies to go beyond what the ISI databases have directly supported and to employ more
sophisticated methods
PENGEMBANGAN MEDIA APLIKASI PERATURAN RESMI BOLA VOLI BERBASIS ANDROID
No full textTujuan dari penelitian ini adalah untuk menghasilkan media aplikasi
berbasis android yang berisi tentang peraturan resmi bola voli yang mudah
diakses serta mengatasi masalah: Kurang mengetahui peraturan resmi bola voli,
Kesalahan dalam informasi dan persepsi serta kurang memahami hubungan antara
aturan-aturan yang ada.
Penelitian ini merupakan penelitian research and development. langkahlangkah
dalam penelitian R & D, yaitu (1) potensi dan masalah, (2) pengumpulan
data, (3) desain produk, (4) validasi desain, (5) revisi desain, (6) uji coba produk,
(7) produk final.
Hasil pengembangan media aplikasi peraturan resmi bola voli berba android dengan nama Smart Volleyball yang terdiri dari sepuluh komponen utama, beranda, fasilitas dan peralatan, tim peserta, format permainan, sikap dalam permainan, penghentian, waktu selang dan memperlambat, pemain libero, sikap peserta, wasit, dan profil. Materi yang disajikan dalam media yaitumateri
tentang peraturan resmi bola voli 2017-2020. Media aplikasi ini dikembangkan
dengan menggunakan alat pengembangan aplikasi android berbasis Adobe Flash
yang bisa diakses melalui Google Play Store
Liftings for noncomplete probability spaces
No full textThe current state of knowledge concerning liftings for noncomplete probability spaces is discussed. This is a somewhat expanded version of the author's talk given at the 1991 Summer Conference on General Topology and Applications in Honor of Mary Ellen Rudin and Her Work.PT: S; CR: BURKE MR, IN PRESS P AM MATH S BURKE MR, 1991, ISRAEL J MATH, V73, P33 BURKE MR, 1992, ISRAEL J MATH, V79, P289 CARLSON T, THEOREM LIFTING CHRISTENSEN JPR, 1974, TOPOLOGY BOREL STRUC FREMLIN DH, 1989, HDB BOOLEAN ALGEBRAS, P877 INOESCUTULCEA A, 1966, 5TH P BERK S MATH ST, V2 IONESCUTULCEA A, 1967, CONTRIBUTIONS PROB 1, P63 IONESCUTULCEA A, 1969, TOPICS THEORY LIFTIN JECH TJ, 1978, SET THEORY JOHNSON RA, 1980, P AM MATH SOC, V80, P234 JUST W, IN PRESS T AM MATH S KUPKA J, 1983, INDIANA U MATH J, V32, P717 LOSERT V, 1983, LNM, V1080, P95 MAHARAM D, 1958, P AM MATH SOC, V9, P987 SHELAH S, 1983, ISRAEL J MATH, V45, P90 TALAGRAND M, 1982, P AM MATH SOC, V84, P379 VONNEUMANN J, 1931, CRELLES J MATH, V165, P109; NR: 18; TC: 0; J9: ANN N Y ACAD SCI; PG: 4; GA: BZ86BSource type: Electronic(1
Hansen, Lee (Lee R.). Union, non-union, and managerial pay plan state employees, 2008-2019
No full text1 online resource (2 pages)"July 1, 2021."Provides the number of union and non-union state employees in each of the last 14 years. Also provides the number of state employees paid under the state's managerial pay plan during each of those years. Updates OLR research report 2019-R-011
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