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Cryptanalysis of Selected Stream Ciphers

Popular Abstract in Swedish Kryptering kan användas när man vill hålla något viktigt meddelande hemligt, till exempel vid en bankbetalning på Internet. Men hur vet man att krypteringsalgoritmen (sättet att kryptera på) är tillräckligt säker? Hur vet man att ingen kan läsa vårt meddelande eller ändra i det så att, till exempel, en överföring av pengar från ett konto till ett annat går till någon heThe aim of this dissertation is to show some cryptanalytical results on a selection of stream ciphers. We have grouped theory and results into three main parts. The first part focuses on the FCSR-based constructions X-FCSR and F-FCSR-H v3. For the X-FCSR family of stream ciphers we perform a severe state recovery attack. This attack works for both X-FCSR-128 and X-FCSR-256. We then develop a gen

Near vacuum ultraviolet luminescence of Gd3+ and Er3+ ions generated by super saturation upconversion processes

Near vacuum ultraviolet (UV) upconversion (UC) emissions with a spectral resolution of 1 nm, from the (6)G(J), D-6(J), I-6(J), P-6(J) levels of Gd3+ and the L-2(17/2), D-4(7/2), H-2(2)(9/2), D-2(5/2), (4)G(7/2), K-2(13/2), P-2(3/2) levels of Er3+, were observed under 974 nm laser excitation. Mechanism analyses illustrate that successive energy transfers (ETs) from Yb3+ to Er3+ generate UV UC radia

Coupled heat and moisture transfer in multi-layer building materials

A dynamic mathematical model for simulating the coupled heat and moisture migration through multilayer porous building materials was proposed. Vapor content and temperature were chosen as the principal driving potentials. The discretization of the governing equations was done by the finite difference approach. A new experimental set-up was also developed in this study. The evolution of transient t

False expectations : Reconsidering the role of informal venture capital in closing the regional equity gap

The role of informal venture capital in entrepreneurial process and economic development is increasingly recognized by scholars and policy-makers around the world. Much of the attention that this form of financing has received during the last couple of decades is due to its potential to bridge the regional equity gap. This study is concerned with regional distribution of informal venture capital a

Ett landskap byter skepnad : förändring och kontinuitet i Risebjärsområdet under 300 år

Det område som idag kallas Strövområdet Arriesjön har bytt skepnad flera gånger under de senaste tre hundra åren. De processer och den historia som åstadkommit dessa förändringar speglas i de två historiska kapitlen. Men i det här kapitlet ger vi en översikt över områdets rent fysiska förändringar med hjälp av de flesta kartor och flygfoton som finns tillgängliga, från den första kartbilden 1702 t

MAGNETIC RESONANCE IMAGING FOR NONINVASIVE ANALYSIS OF FAT STORAGE IN MIGRATORY BIRDS

Many bird species migrate long distances without any food intake and must optimize storage of energy with respect to minimization of aerodynamic drag. To contribute to the understanding of this issue, we investigated, by magnetic resonance imaging (MRI), spatial distributions of body fat during the accumulation process before migration. We collected data from 12 Lesser Whitethroats (Sylvia curruca

Experiencing challenges when implementing active management of third stage of labor (AMTSL) : a qualitative study with midwives in Accra, Ghana

BACKGROUND: Post-partum hemorrhage (PPH) is the major cause of maternal mortality in Ghana and worldwide. Active management of the third stage of labor (AMTSL) is a globally recommended three-step method that in clinical trials has been proven effective in prevention of PPH. The AMTSL guidelines were introduced in 2003, modified in 2006, and has been part of the national guidelines in Ghana since

Molecular studies on streptococcal surface proteins

Streptococcus agalactiae and Streptococcus pyogenes are two related human pathogens causing different diseases. This thesis focuses on a number of surface proteins expressed by S. agalactiae and S. pyogenes and, more specifically, the molecular and biological characterization of these proteins. The first paper describes the novel Blr protein of S. agalactiae, which together with the previously des

Equilibrium bunch density distribution with passive harmonic cavities in a storage ring

The MAX IV storage rings, currently under construction in Lund, Sweden, will use third harmonic cavities operated passively to lengthen the bunches and alleviate collective instabilities. These cavities are an essential ingredient in the MAX IV design concept and are required for achieving the final design goals in terms of stored current, beam emittance, and beam lifetime-such performance challen

Lithium and brain plasticity - studies on glial cell changes and electroconvulsive treatment-induced amnesia in rats

Depression and bipolar disorder, collectively known as mood disorders, are devastating, common and often chronic illnesses. Imaging studies of patients with mood disorders have demonstrated structural changes in several brain regions implicated in mood regulation. Furthermore, bipolar disorder is associated with white matter abnormalities and post mortem analysis of brain tissue from patients with

Single and multi-user cooperative MIMO in a measured urban macrocellular environment

We study the potential benefits of cooperative multiple-input multiple-output signaling from multiple coherent base stations with one or more mobile stations in an urban macrocellular environment at 2.66 GHz. The analysis uses fully-coherent measurements of the channel from three base stations to a single mobile station equipped with four antennas. The observed channels are used to explore the gai

Muscle function and physical activity in pre-pubertal school children

Popular Abstract in Swedish Bakgrund: Regelbunden fysisk aktivitet och träning anses som en livsstilsfaktor som kan förbättra muskelstyrkan, skelettet, konditionen och kroppssammansättningen. För barn och ungdomar är fysisk aktivitet inte bara viktigt för att träna de muskulära funktionerna, koordinationen och balansen. I ett större perspektiv kan en fysiskt aktiv livsstil också minska risken för Background: Regular participation in physical activity or organized exercise is regarded as one important lifestyle factor that could improve musculoskeletal health, fitness and body composition. For children and adolescents physical activity is important not only in training of the neuromuscular system, coordination and balance, but in a wider perspective, for adopting a lifestyle that possibly r

Investigation of local flame structures and statistics in partially premixed turbulent jet flames using simultaneous single-shot CH and OH planar laser-induced fluorescence imaging

We report on the application of simultaneous single-shot imaging of CH and OH radicals using planar laser-induced fluorescence (PLIF) to investigate partially permixed turbulent jet flames. Various flames have been stabilized on a coaxial jet flame burner consisting of an outer and an inner tube of diameter 22 and 2.2 mm, respectively. From the outer tube a rich methane/air mixture was supplied at

Screening for alpha1-antitrypsin deficiency in Lithuanian patients with COPD

Background: Alphal-antitrypsin (AAT) deficiency is an under-diagnosed condition in patients with chronic obstructive pulmonary disease (COPD). The objective of the present screening was to estimate the AAT gene frequency and prevalence and to identify AAT deficiency cases in a large cohort of Lithuanian patients with COPD. Methods: A nationwide program of AAT deficiency was conducted in 1167 COPD

Make-or-Buy Decisions and the Manipulability of Performance Measures

The make-or-buy decision is analyzed in a simple framework combining contractual incompleteness with the existence of an imperfect but contractible performance measure. Contractual incompleteness gives rise to two regimes, identified with make and buy. The performance measure on which comprehensive contracts can be written is imperfect in the sense of being subject to manipulation. The performance