Cryptoraptor : high throughput reconfigurable cryptographic processor for symmetric key encryption and cryptographic hash functions

textIn cryptographic processor design, the selection of functional primitives and connection structures between these primitives are extremely crucial to maximize throughput and flexibility. Hence, detailed analysis on the specifications and requirements of existing crypto-systems plays a crucial role in cryptographic processor design. This thesis provides the most comprehensive literature review that we are aware of on the widest range of existing cryptographic algorithms, their specifications, requirements, and hardware structures. In the light of this analysis, it also describes a high performance, low power, and highly flexible cryptographic processor, Cryptoraptor, that is designed to support both today's and tomorrow's encryption standards. To the best of our knowledge, the proposed cryptographic processor supports the widest range of cryptographic algorithms compared to other solutions in the literature and is the only crypto-specific processor targeting the future standards as well. Unlike previous work, we aim for maximum throughput for all known encryption standards, and to support future standards as well. Our 1GHz design achieves a peak throughput of 128Gbps for AES-128 which is competitive with ASIC designs and has 25X and 160X higher throughput per area than CPU and GPU solutions, respectively.Electrical and Computer Engineerin

Towards quantitative high-throughput 3D localization microscopy

Advances in light microscopy have allowed circumventing the diffraction barrier, once thought to be the ultimate resolution limit in optical microscopy, and given rise to various superresolution microscopy techniques. Among them, localization microscopy exploits the blinking of fluorescent molecules to precisely pinpoint the positions of many emitters individually, and subsequently reconstruct a superresolved image from these positions. While localization microscopy enables the study of cellular structures and protein complexes with unprecedented details, severe technical bottlenecks still reduce the scope of possible applications. In my PhD work, I developed several technical improvements at the level of the microscope to overcome limitations related to the photophysical behaviour of fluorescent molecules, slow acquisition rates and three-dimensional imaging. I built an illumination system that achieves uniform intensity across the field-of view using a multi-mode fiber and a commercial speckle-reducer. I showed that it provides uniform photophysics within the illuminated area and is far superior to the common illumination system. It is easy to build and to add to any microscope, and thus greatly facilitates quantitative approaches in localization microscopy. Furthermore, I developed a fully automated superresolution microscope using an open-source software framework. I developed advanced electronics and user friendly software solutions to enable the design and unsupervised acquisition of complex experimental series. Optimized for long-term stability, the automated microscope is able to image hundreds to thousands of regions over the course of days to weeks. First applied in a system-wide study of clathrin-mediated endocytosis in yeast, the automated microscope allowed the collection of a data set of a size and scope unprecedented in localization microscopy. Finally, I established a fundamentally new approach to obtain three-dimensional superresolution images. Supercritical angle localization microscopy (SALM) exploits the phenomenon of surface-generated fluorescence arising from fluorophores close to the coverslip. SALM has the theoretical prospect of an isotropic spatial resolution with simple instrumentation. Following a first proof-of-concept implementation, I re-engineered the microscope to include adaptive optics in order to reach the full potential of the method. Taken together, I established simple, yet powerful, solutions for three fundamental technical limitations in localization microscopy regarding illumination, throughput and resolution. All of them can be combined within the same instrument, and can dramatically improve every cutting-edge microscope. This will help to push the limit of the most challenging applications of localization microscopy, including system-wide imaging experiments and structural studies

Annual Report 2016 Institute of Resource Ecology

The Institute of Resource Ecology (IRE) is one of the eight institutes of the Helmholtz-Zentrum Dresden – Rossendorf (HZDR). The research activities are mainly integrated into the program “Nuclear Waste Management, Safety and Radiation Research (NUSAFE)” of the Helmholtz Association (HGF) and focused on the topics “Safety of Nuclear Waste Disposal” and “Safety Research for Nuclear Reactors”..

The effect of extensional flow on shear viscosity

Shear rheology is conventionally studied under pure shearing flows, rather than more realistic mixed flows. Moving parallel surfaces and capillary rheometery are examples of the former, whilst the latter occurs whenever a flow accelerates or decelerates creating an additional component of extension, e.g. on passing through an industrial extrusion die. We postulate and gather supporting evidence that shear rheology is a function of not only shear, but both shear and extension rate, a factor with important consequences for fibre spinning and extrusion operations. The direction, as well as rate, of extensional deformation is important. A novel two-phase flow, planar extension experiment is developed and the surface coatings necessary to control the interface structure identified. Shear viscosity evolution is monitored, in-situ, under extensional flow, by optically measuring shear rates either side of a test fluid – reference fluid interface; issues due to optical refraction are critically addressed. Preliminary evidence is shown for a 1.2wt% 4x10^6 MW PEO solution that parallel (+ve) extensional flow, on the order of 11.5s-1 , causes a reduction in shear viscosity, and perpendicular (-ve) causes an increase in shear viscosity, supporting the hypothesis. A framework for a comparison experiment, with the same shear history but without extension, is presented. As part of this work, design criteria for planar hyperbolic extensional channels are critically assessed. In particular, expanding a hyperbola entrance region would maximise total Hencky strain, yet this region is almost never given rationalised consideration in literature. In this region the basis for the hyperbolic profile breaks down, and a new profiling strategy and channel form are presented, which is found to only differ significantly in this inlet region. A useful design limit of 130 degrees on channel inlet angle is identified. The new profile is compared to a hyperbolic profile through the use of CFD for wall slip flow, and a slight improvement in extension rate uniformity along the centreline found. Deviations are contrasted against assumptions made in the profiling strategy: comments are made with regards the possibility for “internal” shear to occur, and non-uniform extension rates are accordingly found to exist between streamlines in these channels despite the use of full wall slip in the simulations

Single-molecule techniques in biophysics : a review of the progress in methods and applications

Single-molecule biophysics has transformed our understanding of the fundamental molecular processes involved in living biological systems, but also of the fascinating physics of life. Far more exotic than a collection of exemplars of soft matter behaviour, active biological matter lives far from thermal equilibrium, and typically covers multiple length scales from the nanometre level of single molecules up several orders of magnitude to longer length scales in emergent structures of cells, tissues and organisms. Biological molecules are often characterized by an underlying instability, in that multiple metastable free energy states exist which are separated by energy levels of typically just a few multiples of the thermal energy scale of kBT, where kB is the Boltzmann constant and T the absolute temperature, implying complex, dynamic inter-conversion kinetics across this bumpy free energy landscape in the relatively hot, wet environment of real, living biological matter. The key utility of single-molecule biophysics lies in its ability to probe the underlying heterogeneity of free energy states across a population of molecules, which in general is too challenging for conventional ensemble level approaches which measure mean average properties. Parallel developments in both experimental and theoretical techniques have been key to the latest insights and are enabling the development of highly-multiplexed, correlative techniques to tackle previously intractable biological problems. Experimentally, technological developments in the sensitivity and speed of biomolecular detectors, the stability and efficiency of light sources, probes and microfluidics, have enabled and driven the study of heterogeneous behaviours both in vitro and in vivo that were previously undetectable by ensemble methods..