15,683 research outputs found
Dispersion managed mode-locking dynamics in a Ti:Sapphire laser
We present what is to our knowledge the most complete 1-D numerical analysis
of the evolution and the propagation dynamics of an ultrashort laser pulse in a
Ti:Sapphire laser oscillator. This study confirms the dispersion managed model
of mode-locking, and emphasizes the role of the Kerr nonlinearity in generating
mode-locked spectra with a smooth and well-behaved spectral phase. A very good
agreement with preliminary experimental measurements is found.Comment: 11 pages, 4 figures, submitted to Optics Letter
Harnack's Inequality for Parabolic De Giorgi Classes in Metric Spaces
In this paper we study problems related to parabolic partial differential
equations in metric measure spaces equipped with a doubling measure and
supporting a Poincare' inequality. We give a definition of parabolic De Giorgi
classes and compare this notion with that of parabolic quasiminimizers. The
main result, after proving the local boundedness, is a scale and location
invariant Harnack inequality for functions belonging to parabolic De Giorgi
classes. In particular, the results hold true for parabolic quasiminimizers
Sistem Pendukung Keputusan Pemilihan Pts Di Lhokseumawe Menggunakan Metode Fuzzy Ahp Berbasis Web
Sistem Pendukung Keputusan pemilihan PTS ini bertujuan untuk memberikan dukungan pengambilan keputusan untuk pemilihan sebuah PTS di Lhokseumawe. Pada sistem ini terdapat 11 alternatif perguruan tinggi swasta dan ada 6 kriteria yang digunakan oleh sistem. Sistem ini menggunakan metode fuzzy untuk kriteriayang bobot nilainya tidak tetap, kriteria tersebut diantaranya jumlah lulusan, Jarak dengan kota, Biaya pendidikan, jumlah dosen dan pendidikan dosen serta menggunakan metode Analytic Hierarchy Process (AHP) yaitu untuk perangkingan Perguruan Tinggi yang dipilih oleh user. Pemberian nilai fuzzy berlaku untuk setiap kriteria yang ada. Pada sistem ini juga terdapat 2 proses yakni proses pemilihan perguruan tinggi swasta dan proses membandingkan tingkat kepentingan antar kriteria. Perhitungan fuzzy pada sistem ini tidak dilakukan di dalam sistem melainkan di input oleh admin sistem yang telah dicari terlebih dahulu nilai fuzzy kriteria untuk tiap alternatif yang ada. Hasil dari proses fuzzy dan AHP dalam aplikasi ini akan menghasilkan perangkingan untuk alternatif yang dipilih oleh user
Valence-bond theory of highly disordered quantum antiferromagnets
We present a large-N variational approach to describe the magnetism of
insulating doped semiconductors based on a disorder-generalization of the
resonating-valence-bond theory for quantum antiferromagnets. This method
captures all the qualitative and even quantitative predictions of the
strong-disorder renormalization group approach over the entire experimentally
relevant temperature range. Finally, by mapping the problem on a hard-sphere
fluid, we could provide an essentially exact analytic solution without any
adjustable parameters.Comment: 5 pages, 3 eps figure
Performing the Network
SĂ©ance: a networked glossalalia is a networked performance that is part of the media art project, The Perpetual Emotion Project. Both are animated by our interest in the non-instrumental and the non-sensical and in the making of performative events. In this paper we present the work as practice-led research, which contributes to the understanding and development of what we identify as performative media art. This paper is an expanded version of a paper presented at E-Performance and Plug-ins, UNSW, 2006
3d Modularity
We find and propose an explanation for a large variety of modularity-related
symmetries in problems of 3-manifold topology and physics of 3d
theories where such structures a priori are not manifest. These modular
structures include: mock modular forms, Weil
representations, quantum modular forms, non-semisimple modular tensor
categories, and chiral algebras of logarithmic CFTs.Comment: 119 pages, 10 figures and 20 table
Elliptic Genera and 3d Gravity
We describe general constraints on the elliptic genus of a 2d supersymmetric
conformal field theory which has a gravity dual with large radius in Planck
units. We give examples of theories which do and do not satisfy the bounds we
derive, by describing the elliptic genera of symmetric product orbifolds of
, product manifolds, certain simple families of Calabi-Yau hypersurfaces,
and symmetric products of the "Monster CFT." We discuss the distinction between
theories with supergravity duals and those whose duals have strings at the
scale set by the AdS curvature. Under natural assumptions we attempt to
quantify the fraction of (2,2) supersymmetric conformal theories which admit a
weakly curved gravity description, at large central charge.Comment: 50 pages, 9 figures, v2: minor corrections to section
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