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Visar resultat 1 - 5 av 9 avhandlingar som matchar ovanstående sökkriterier.

1. 1. Flash Diffractive Imaging in Three Dimensions

   Författare :Tomas Ekeberg; Janos Hajdu; Keith Nugent; Uppsala universitet; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; X-ray; diffraction; mimivirus; three dimensional; phase retrieval; EMC; manifold embedding; CXI; FEL; free-electron laser; single particle; Physics with specialization in Biophysics; Fysik med inriktning mot biofysik;

   Sammanfattning : During the last years we have seen the birth of free-electron lasers, a new type of light source ten billion times brighter than syncrotrons and able to produce pulses only a few femtoseconds long. One of the main motivations for building these multi-million dollar machines was the prospect of imaging biological samples such as proteins and viruses in 3D without the need for crystallization or staining. LÄS MER

3. 2. Digital Geometry and Khalimsky Spaces

   Författare :Erik Melin; Christer Kiselman; Gunilla Borgefors; Mikael Passare; Jean Serra; Uppsala universitet; []
   Nyckelord :Applied mathematics; Khalimsky topology; digital geometry; digital topology; Alexandrov space; digital surface; digital curve; digital manifold; continuous extension; smallest-neighborhood space; image processing; Tillämpad matematik;

   Sammanfattning : Digital geometry is the geometry of digital images. Compared to Euclid’s geometry, which has been studied for more than two thousand years, this field is very young.Efim Khalimsky’s topology on the integers, invented in the 1970s, is a digital counterpart of the Euclidean topology on the real line. LÄS MER

4. 3. Expressing emotions through vibration for perception and control

   Författare :Shafiq ur Réhman; Li Liu; Xiaoyi Jiang; Umeå universitet; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; NATURVETENSKAP; NATURAL SCIENCES; Multimodal Signal Processing; Mobile Communication; Vibrotactile Rendering; Locally Linear Embedding; Object Detection; Human Facial Expression Analysis; Lip Tracking; Object Tracking; HCI; Expectation-Maximization Algorithm; Lipless Tracking; Image Analysis; Visually Impaired.; Signal processing; Signalbehandling; Image analysis; Bildanalys; Computer science; Datavetenskap; Telecommunication; Telekommunikation; Systems engineering; Systemteknik; datoriserad bildanalys; Computerized Image Analysis; business data processing; administrativ databehandling; Electronics; elektronik; Systems Analysis; systemanalys;

   Sammanfattning : This thesis addresses a challenging problem: “how to let the visually impaired ‘see’ others emotions”. We, human beings, are heavily dependent on facial expressions to express ourselves. A smile shows that the person you are talking to is pleased, amused, relieved etc. LÄS MER

5. 4. G-structures and Families of Isotropic Submanifolds in Complex Contact Manifolds

   Författare :Patrik Hellgren; Sergei Merkulov; Henrik Pedersen; Stockholms universitet; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Differential geometry; twistor; G-structures; deformation; MATHEMATICS; MATEMATIK; matematik; Mathematics;

   Sammanfattning : We study a generalized twistor correspondence between irreducible G-structures (with torsion in general) on complex manifolds Z and moduli spaces M of deformations of isotropic homogeneous submanifolds X in complex contact manifolds Y.For any irreducible G-structure on a complex manifold M we present an explicit construction of a contact manifold (a generalized twistor space) Y with contact line bundle L and a family F of isotropic submanifolds X in Y having M as its moduli space. LÄS MER

7. 5. Entropy and Speech

   Författare :Mattias Nilsson; Bastian Kleijn; Sören Holdt Jensen; KTH; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; speech representation; energy concentration; entropy estimation; manifolds; Acoustics; Akustik;

   Sammanfattning : In this thesis, we study the representation of speech signals and the estimation of information-theoretical measures from observations containing features of the speech signal. The main body of the thesis consists of four research papers. Paper A presents a compact representation of the speech signal that facilitates perfect reconstruction. LÄS MER