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51.
Martin Loeser Lorenzo Occhi Christian Vélez Raffaele Rezzonico Bernd Witzigmann 《Optical and Quantum Electronics》2006,38(12-14):1069-1075
The impact of self-heating and cavity length on the spectral emission properties of SLEDs is investigated using a state-of-the-art simulation tool. Simulated data are compared to measurements for two InP-based benchmark devices operating around 1300 nm, and excellent agreement is achieved in either case. 相似文献
52.
Uwe Bandelow Mindaugas Radziunas Andrei Vladimirov Bernd Hüttl Ronald Kaiser 《Optical and Quantum Electronics》2006,38(4-6):495-512
We study both theoretically and experimentally typical operation regimes of 40 GHz monolithic mode-locked lasers. The underlying
Traveling Wave Equation model reveals quantitative agreement for characteristics of the fundamental mode-locking as pulse
width and repetition frequency tuning, as well as qualitative agreement with the experiments for other dynamic regimes. Especially
the appearance of stable harmonic mode-locking at 80 GHz has been predicted theoretically and confirmed by measurements. Furthermore,
we derive and apply a simplified Delay-Differential-Equation model which guides us to a qualitative analysis of bifurcations
responsible for the appearance and the breakup of different mode-locking regimes. Higher harmonics of mode-locking are predicted
by this model as well. 相似文献
53.
Beat Jaggi Peter Mani-Levitska Bernd Sturmfels Neil White 《Discrete and Computational Geometry》1989,4(1):97-100
We give an easy general construction for uniform oriented matroids with disconnected realization space. This disproves the longstanding isotopy conjecture for simple line arrangements or order types in the plane.The research of Bernd Sturmfels and Neil White was supported in part by the Institute for Mathematics and Its Applications with funds provided by the National Science Foundation. 相似文献
54.
55.
56.
Stevenson NR Schubank RB Shin YM Amaudruz P Delheij PP Healey DC Jennings BK Ottewell DF Sheffer G Smith GR Wait GD Brack JT Feltham A Hanna M Johnson RR Rozon FM Sossi V Vetterli D Weber P Grion N Rui R Kohler M Ristinen RA Mathie EL Tacik R Yeomans M Gossett CA Wagner GJ 《Physical review letters》1990,65(16):1987-1990
57.
Wagner SR Hinshaw DA Ong RA Snyder A Abrams G Adolphsen CE Akerlof C Alexander JP Alvarez M Amidei D Baden AR Ballam J Barish BC Barklow T Barnett BA Bartelt J Blockus D Bonvicini G Boyarski A Boyer J Brabson B Breakstone A Brom JM Bulos F Burchat PR Burke DL Butler F Calvino F Cence RJ Chapman J Cords D Coupal DP DeStaebler HC Dorfan DE Dorfan JM Drell PS Feldman GJ Fernandez E Field RC Ford WT Fordham C Frey R Fujino D Gan KK Gidal G Gladney L Glanzman T Gold MS Goldhaber G Green A 《Physical review letters》1990,64(10):1095-1098
58.
H. v. Brandis F. E. Wagner J. A. Sawicki K. Marcinkowska J. H. Rolston 《Hyperfine Interactions》1990,57(1-4):2127-2131
The state of iridium on Pt?Ir catalysts prepared by impregnation of amorphous silica with H2IrCl6 and H2PtCl6 was studied by193Ir Mössbauer spectroscopy after different steps of preparation. The Ir is adsorbed in its trivalent state, presumably as [IrCl6]3?. Calcination in air at 450°C converts this to IrO2. The metallic clusters formed by subsequent reduction in H2 at 200°C show a strong tendency towards segregation of Ir and Pt and re-oxidize partially when exposed to air at ambient temperature. In both respects the behaviour is similar to that of samples prepared by co-exchange from [Ir(NH3)5Cl]Cl2 and Pt(NH3)4Cl2. H2O. 相似文献
59.
60.
Bernd Sturmfels 《Results in Mathematics》1989,15(3-4):351-360
Final polynomials and final syzygies provide an explicit representation of polynomial identities promised by Hilbert’s Nullstellensatz. Such representations have been studied independently by Bokowski [2,3,4] and Whiteley [23,24] to derive invariant algebraic proofs for statements in geometry. In the present paper we relate these methods to some recent developments in computational algebraic geometry. As the main new result we give an algorithm based on B. Buchberger’s Gröbner bases method for computing final polynomials and final syzygies over the complex numbers. Degree upper bound for final polynomials are derived from theorems of Lazard and Brownawell, and a topological criterion is proved for the existence of final syzygies. The second part of this paper is expository and discusses applications of our algorithm to real projective geometry, invariant theory and matrix theory. 相似文献