Search for dissertations about: "sphere packing"

Showing result 1 - 5 of 9 swedish dissertations containing the words sphere packing.

2. 1. On the ring lemma

   Author : Jonatan Vasilis; Göteborgs universitet; []
   Keywords : NATURVETENSKAP; NATURAL SCIENCES; ring lemma; circle packing; sphere packing; Apollonian; sphere packing;

   Abstract : The sharp ring lemma states that if n ≥ 3 cyclically tangent discs with pairwise disjoint interiors are externally tangent to and surround the unit disc, then no disc has a radius below cn = (F2n-1 + F2n-2 - 1)-1 – where Fk denotes the kth Fibonacci number – and that the lower bound is attained in essentially unique Apollonian configurations. Here we give a proof by transforming the problem to a class of strip configurations, after which we closely follow a method of proof due to Aharonov and Stephenson. READ MORE

4. 2. Modulation Optimization for Noncoherent Optical Systems

   Author : Johnny Karout; Chalmers tekniska högskola; []
   Keywords : NATURVETENSKAP; NATURAL SCIENCES; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Direct detection; noncoherent communications; lattice codes; mutual information; fiber-optical communications; intensity modula- tion; sphere packing.; infrared communications; free-space optical communications;

   Abstract : There has been a significant improvement in high-speed electronics and optical components over the past few years, and this is one of the key enabling factors for high data rate transmission. Moreover, multi- level modulation formats, which encode information onto the carrier’s amplitude and phase, are necessary to increase the spectral efficiency of communication systems. READ MORE

5. 3. Signaling for Optical Intensity Channels

   Author : Johnny Karout; Chalmers tekniska högskola; []
   Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; lattice codes; mutual information; intensity modulation; noncoherent communications; Direct detection; sphere packing.; infrared communications; free-space optical communications; fiber-optical communications;

   Abstract : With the growing popularity of social media services, e-commerce, and many other internet-based services, we are witnessing a rapid growth in the deployment of data centers and cloud computing platforms. As a result, the telecommunications industry has to continue providing additional network capacity to meet the increasing demand for bandwidth. READ MORE

6. 4. Packing effects in palladium(II) and platinum(II) compounds, X-ray crystallography

   Author : Maria Johansson; Kemiska institutionen; []
   Keywords : NATURVETENSKAP; NATURAL SCIENCES; Inorganic chemistry; Platinum II ; Palladium II ; Half-normal probability plots; X-ray crystallography; Packing effects; Oorganisk kemi;

   Abstract : This thesis focuses on i) the effect of packing on the molecular geometry ii) packing arrangements of neutral Pd(II) and Pt(II) complexes iii) the trans influence in Pt(II) complexes iv) the differences in bonding in corresponding Pd(II) and Pt(II) complexes and v) the geometry of Pd(II) complexes with potential catalytic properties. Detailed three-dimensional structural information at the atomic level can be obtained from X-ray crystallography. READ MORE

7. 5. Redox reactions and structure - properties relations in mixed alkali/alkaline earth glasses : The role of antimony oxides during the fining process- A structural study of copper(I) and copper(II)

   Author : Lina Grund Bäck; Bo Jonson; Leena Hupa; Linnéuniversitetet; []
   Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Fining; oxygen activity; redox reactions; mixed alkali effect; mixed alkali silicate glasses; copper; antimony; Glasteknologi; Glass Technology;

   Abstract : It is important to optimize glass compositions for their specific purpose but also for the efficiency of the production process, the manufacturing of glass. This will be beneficial economically and environmentally. READ MORE