Search results

Filter

Filetype

Your search for "*" yielded 526602 hits

A coding theoretic approach to attack certain stream ciphers

We present a coding theoretic approach to the problem the initial state recovery of a linear feedback shift register when a noisy output sequence is given. Our work is focused on the investigation of the asymptotical behaviour of the recovery process. We give two algorithms which will work for shift registers with arbitrary feedback polynomial. Furthermore, the number of required given noisy symbo

On the construction of authentication codes with secrecy and codes withstanding spoofing attacks of order L ≥ 2

We present an analysis of some known cartesian authentication codes and their modification into authentication codes with secrecy, with transmission rate R = r/n, where n = 2, 3, …, and 1 ≤ r ≤ n - 1 using (n - r)(r + 1) q-ary key digits. For this purpose we use a grouping technique. Essentially the same key grouping technique is used for the construction of codes that withstand spoofing attacks o

Stroboscopic operando spectroscopy of the dynamics in heterogeneous catalysis by event-averaging

Heterogeneous catalyst surfaces are dynamic entities that respond rapidly to changes in their local gas environment, and the dynamics of the response is a decisive factor for the catalysts’ action and activity. Few probes are able to map catalyst structure and local gas environment simultaneously under reaction conditions at the timescales of the dynamic changes. Here we use the CO oxidation react

Self-selective formation of ordered 1D and 2D GaBi structures on wurtzite GaAs nanowire surfaces

Scaling down material synthesis to crystalline structures only few atoms in size and precisely positioned in device configurations remains highly challenging, but is crucial for new applications e.g., in quantum computing. We propose to use the sidewall facets of larger III–V semiconductor nanowires (NWs), with controllable axial stacking of different crystal phases, as templates for site-selectiv

Conflict in Colours : A comparative study of republican and loyalist murals in Belfast

”Conflict in Colours” är en avhandling som fokuserar på historiska narrativs roll i att legitimera och bibehålla konflikter, samt hur dessa narrativ påverkar den begynnande fredsprocessen. Genom att studera det inneboende kulturella våldet i dessa narrativ har jag visat hur kulturellt våld är en essentiell del i att legitimera, påverka och bibehålla det antagonistiska förhållandet mellan parterna Conflict in Colours is a book about the role of cultural violence in maintaining and transferring conflict situations by investigating republican and loyalist murals in Belfast during the Troubles and the Northern Irish peace process. During several decades, the people of Northern Ireland have endured warlike situations before the peace agreement in 1998. This doctoral thesis examines the ways/how

Field dependence of superfluid density in β-PdBi2

Specific heat and small-angle neutron scattering measurements have been performed on the superconductor β-PdBi2. Whereas models with a uniform gap do not yield an adequate description of the temperature-dependent specific heat and the temperature and magnetic field dependence of the SANS intensity, fits to a heuristic model with two gap parameters agree well with both data sets. The fact that two

Role of dispersion and compression ratio on the temporal contrast of SPM-broadened post-compressed pulses

Nonlinear pulse post-compression, mainly enabled by self-phase modulation (SPM), opens new avenues towards high peak power laser pulses at high average power while bypassing the need for a gain medium with large bandwidth. However, SPM-induced spectral broadening typically introduces spectral amplitude modulations as well as a chirp of third and higher orders, limiting the temporal contrast of the

Intra-Burst Pulse Characterization of a High-Power Post-Compressed Yb:YAG Laser at 100 kHz Repetition Rate

High-average power Ytterbium (Yb) laser systems are playing an increasingly important role in ultrafast science e.g. as pump lasers for optical parametric amplifiers or directly as ultrafast sources. The gain bandwidth of Yb limits the pulse duration to a few 100 fs up to about 1 ps. However, many applications, such as attosecond physics or X-ray Free Electron Laser (FEL) science, would greatly be

Entering, enduring and exiting : the durability of shared mobility arrangements and habits

Car sharing could support a transition away from private vehicle ownership and use. Attempts to understand participation in car sharing have primarily focused on minor and major disruptions which catalyse change in practices. This paper examines how processes of entering, continuing or exiting car sharing systems unfold in Norway, the Netherlands, Sweden and the UK. Car sharing is conceptualised a

No title

Biotechnology and genetic engineering raise a number of new ethical problems. Consequently, over the past 15 years, several European countries, including the Nordic countries, have passed new laws in an attempt to deal with the ethical problems posed by biotechnology. These developments raise the question of how to formulate legislation to regulate both the technical and ethical aspects of biotech

Disrupting ‘A Man’s World’: Gender, Technology, and Class in Vietnam’s Global Heavy Industry.

Only rarely is Vietnam's global heavy industry studied from an anthropological perspective in either its gender or its class dimensions. This article contributes new insights into the ways in which the interagential dynamics of gender and technology from shopfloor to engineer offices coproduce social orders in contesting and perpetuating essentializing notions of femininity and masculinity. Blue-c

Enzymology and significance of protein histidine methylation

Cells synthesize proteins using 20 standard amino acids and expand their biochemical repertoire through intricate enzyme-mediated post-translational modifications (PTMs). PTMs can either be static and represent protein editing events or be dynamically regulated as a part of a cellular response to specific stimuli. Protein histidine methylation (Hme) was an elusive PTM for over 5 decades and has on

Monitoring the standard – here, now and in person : Detecting accessibility faults as an engaged citizen

This chapter analyses volunteer work for identifying and reporting accessibility faults in urban settings. By looking closely at how people monitor adherence to the accessibility standards of laws and human rights, it is possible to recognise and understand their concrete fight against exclusion and discrimination. The author uses ethnographic data from go-alongs with two ‘accessibility detectives