Compilation Optimizations to Enhance Resilience of Big Data Programs and Quantum Processors

Modern computers can experience a variety of transient errors due to the surrounding environment, known as soft faults. Although the frequency of these faults is low enough to not be noticeable on personal computers, they become a considerable concern during large-scale distributed computations or systems in more vulnerable environments like satellites. These faults occur as a bit flip of some value in a register, operation, or memory during execution. They surface as either program crashes, hangs, or silent data corruption (SDC), each of which can waste time, money, and resources. Hardware methods, such as shielding or error correcting memory (ECM), exist, though they can be difficult to implement, expensive, and may be limited to only protecting against errors in specific locations. Researchers have been exploring software detection and correction methods as an alternative, commonly trading either overhead in execution time or memory usage to protect against faults. Quantum computers, a relatively recent advancement in computing technology, experience similar errors on a much more severe scale. The errors are more frequent, costly, and difficult to detect and correct. Error correction algorithms like Shor’s code promise to completely remove errors, but they cannot be implemented on current noisy intermediate-scale quantum (NISQ) systems due to the low number of available qubits. Until the physical systems become large enough to support error correction, researchers instead have been studying other methods to reduce and compensate for errors. In this work, we present two methods for improving the resilience of classical processes, both single- and multi-threaded. We then introduce quantum computing and compare the nature of errors and correction methods to previous classical methods. We further discuss two designs for improving compilation of quantum circuits. One method, focused on quantum neural networks (QNNs), takes advantage of partial compilation to avoid recompiling the entire circuit each time. The other method is a new approach to compiling quantum circuits using graph neural networks (GNNs) to improve the resilience of quantum circuits and increase fidelity. By using GNNs with reinforcement learning, we can train a compiler to provide improved qubit allocation that improves the success rate of quantum circuits

Determination of local material properties of OSB sample by coupling advanced imaging techniques and morphology-based FEM simulation

This is the publisher’s final pdf. The published article is copyrighted by Walter de Gruyter & Co. and can be found at: http://www.degruyter.com/.The goal was to determine local mechanical properties inside of oriented strand board (OSB) based on a realistic morphology-based finite element (FE) model and data acquired from a physical test performed on the same material. The spatial information and local grayscale intensity from CT-scans obtained from small OSB sample was transformed into a 2D regular morphology-based FE mesh with corresponding material properties. The model was then used to simulate the actual compression test performed on the specimen using simplified boundary conditions. The simulated strain fields from the model were compared with the actual strain field measured on the specimen surface during the compression test by means of a full-field optical method, named digital image correlation (DIC). Finally, the original set of material properties was adjusted by an iterative procedure to minimize the difference between the simulated and the measured strain data. The results show that the developed procedure is useful to find local material properties as well as for morphological modeling without the need of segmentation of the image data. The achieved results serve as a prerequisite for full 3D analyses of the complex materials

I Am My Identity Kit : using Artifact Data in Research on Identity

Este texto se presentó como comunicación al II Congreso Internacional de Etnografía y Educación: Migraciones y Ciudadanías. Universidad Autónoma de Barcelona, Barcelona, 5-8 Septiembre 2008.This presentation addresses how to collect and analyze artifacts in ethnographic and qualitative research, and the value of using artifacts in research which seeks to describe and interpret the identities that research participants construct. We believe that artifacts can be very useful in such research, because they tell us about the every day, taken-for-granted cultural meanings that people give to their surroundings, the things they make, their tools, toys, clothing, and even natural objects that have been given cultural meanings. Artifacts can be used to determine what people value, and how they adapt the resources they have to their needs. However, artifacts most often consist simply of souvenirs and clothing collected by researchers; they usually are under-utilized as research data themselves. Artifacts are large and lumpy and difficult to ship home. They may be immoveable, as is the case with features of the natural environment-mountains, urban environments, etc. In every case, they are difficult to analyze directly because research privileges data that can be manipulated easily- numbers and words. Nonetheless, we believe that artifacts can provide both a stimulus for collecting rich information about people and their culture, and also a window into otherwise unexamined questions in anthropological, sociological, educational, and other social science research. Visual anthropology and sociology has made use of wide photographs to supplement verbal description (Collier and Collier 1986). Anthropologists also have analyzed artifacts in the process of describing manufacturing and economies in communities they study. However, we believe that artifacts have been little used in studies of education (but see LeCompte and Preissle 1993), and especially in the study of processes of identity construction and maintenance. In an era of highly mobile populations, home culture no longer provides the sole and stable anchor for identity. Many people migrate back and forth between several countries, communities and cultures. Personal and community identity, then, must adapt to several environments at once. We believe that migrants form hybrid identities made up of components from multiple cultures and environments. Examining the artifacts that they use and surround themselves with can provide a window into dynamic processes of identity construction. In summary, as ethnographic researchers we realize the value that artifacts have had for us, as data objects and as a way to create conversations with participants about the objects, their functions, and their uses historically and currently. We believe that this issue remains insufficiently examined in the literature

Essai de Phytoclimatologie dynamique dans le nord du Portugal, et réflexion sur les climats mediterranéens portugais

A STUDY IN DYNAMIC PHYTOCLIMATOLOGY IN THE NORTH OF PORTUGAL AND THE QUESTION OF MEDITERRANEAN CLIMATES IN PORTUGAL - The climate-vegetation relation in the north of Portugal is studied in a new way. The dynamic continuity of the climate is revealed by the existence of botanical "continuums". The vegetation sampling was made along a continous NW-SE line transect, 185 km long, parallel to the strongest pluviometric gradient. Multivariate analysis and some of the applications of the information theory were used in the floristic study. In the climate study the spatial patterns of daily values of precipitation were analysed for a period of three years. This description was also done by means of multivariate analysis, including CCA for the aerological explanation. A "threshold of hydric satisfaction", around 1400mm of mean annual rainfall seems to determine the existence of an Atlantic vegetation, between the Alvão and Falperra mountains and the Ocean. This vegetation is homogeneous because it does not respond to the udometric variations above this level. To the east, the Atlantic vegetation rapidly dissapears. The comparison between daily precipitation regimes in the different stations and the dynamic interpretation of the differences bring some light to the discussion about the climate in the NW of the Iberian Peninsula: is it an Atlantic or a Mediterranean climate? In the maritime coast of Portugal these two influences mingle, as opposed to the sheltered interior provinces

Comparison between homogeneous and heterogeneous field information for plastic material identification

peer reviewedThe accuracy of a Finite Element Simulation for plastic deformation strongly depends on the chosen constitutive laws and the value of the material parameters within these laws. The identification of those mechanical parameters can be done based on homogeneous stress and strain fields such as those obtained in uniaxial tensile tests and simple shear tests performed in different plane material directions. Another way to identify plastic material parameters is by inverse modeling of an experiment exhibiting a heterogeneous stress and strain field. Experimental forces and strains are in this case compared to the simulated ones and it is tried to reduce the difference in a least-squares sense by optimizing the model parameters. The optimization technique used is this case is gradient based, which means that at every iteration a sensitivity calculation has to be performed in order to indicate the direction in which the parameters are to be identified. The basic principle of the inverse modeling procedure as it is used for parameter identification is the generation of a complex and heterogeneous deformation field that contains as much information as possible about the parameters to be identified. One way of obtaining such a non-homogeneous deformation is by altering the geometry of the specimen for a uniaxial test. Another possibility is to make the loading conditions more complex. In this paper both options are actually combined by using a biaxial tensile test on a perforated cruciform specimen. In the present paper, the work hardening of the material is assumed to be isotropic and it is described by a Swift law. The yield locus is modeled by the anisotropic Hill48 criterion. A comparison is made between the identification of the Hill48 parameters based on the one hand on the Lankford coefficients [1] and on the inverse modeling of a biaxial tensile test on the other han

OrthoInspector: comprehensive orthology analysis and visual exploration

<p>Abstract</p> <p>Background</p> <p>The accurate determination of orthology and inparalogy relationships is essential for comparative sequence analysis, functional gene annotation and evolutionary studies. Various methods have been developed based on either simple blast all-versus-all pairwise comparisons and/or time-consuming phylogenetic tree analyses.</p> <p>Results</p> <p>We have developed OrthoInspector, a new software system incorporating an original algorithm for the rapid detection of orthology and inparalogy relations between different species. In comparisons with existing methods, OrthoInspector improves detection sensitivity, with a minimal loss of specificity. In addition, several visualization tools have been developed to facilitate in-depth studies based on these predictions. The software has been used to study the orthology/in-paralogy relationships for a large set of 940,855 protein sequences from 59 different eukaryotic species.</p> <p>Conclusion</p> <p>OrthoInspector is a new software system for orthology/paralogy analysis. It is made available as an independent software suite that can be downloaded and installed for local use. Command line querying facilitates the integration of the software in high throughput processing pipelines and a graphical interface provides easy, intuitive access to results for the non-expert.</p

Numerical modelling of the debonding between CFRP strips and concrete in shear tests under static loads using different approaches

The present paper deals with the finite element (FE) analysis of bond slip between concrete and carbon fiber reinforced polymer (CFRP) strips in a single pull-out test under static loads. The commercial software LS-DYNA is used to simulate the test set-up using a plastic damage material model and an elastic material model for the concrete prism and the unidirectional CFRP strip, respectively. The bond interface between the concrete and the CFRP strip is simulated following three different approaches using a perfect bond model, a cohesive bond model and contact algorithms based on recently developed proposed bond slip models. The numerical model is validated based on experimental test results available from literature. The debonding failure mode and the delamination loads of the CFRP strip are predicted. The numerical results show a good agreement with the experimental data using the cohesive bond model. The perfect bond model gives an overestimation of the delamination loads and of the damage distribution in the concrete prism

Identification of the plastic behavior of aluminum plates under free air explosions using inverse methods and full-field measurements

AbstractThis article describes an inverse method for the identification of the plastic behavior of aluminum plates subjected to sudden blast loads. The method uses full-field optical measurements taken during the first milliseconds of a free air explosion and the finite element method for the numerical prediction of the blast response. The identification is based on a damped least-squares solution according to the Levenberg–Marquardt formulation. Three different rate-dependent plasticity models are examined. First, a combined model based on linear strain hardening and the strain rate term of the Cowper–Symonds model, secondly, the Johnson–Cook model and finally, a combined model based on a bi-exponential relation for the strain hardening term and the strain rate term of the Cowper–Symonds model. A validation of the method and its sensitivity to measurement uncertainties is first provided according to virtual measurements generated with the finite element method. Next, the plastic behavior of aluminum is identified using measurements from real free air explosions obtained from a controlled detonation of C4. The results show that inverse methods can be successfully applied for the identification of the plastic behavior of metals subjected to blast waves. In addition, the material parameters identified with inverse methods enable the numerical prediction of the material’s response with increased accuracy

Sensitivity of Recalibrated Continuous Glucose Monitor Data

Continuous glucose monitors (CGMs) are increasingly used in research settings to examine glucose metabolism in newborn babies. Accuracy of these devices depends on calibration blood glucose (BG) measurements entered into the CGM device. The potential impact of variations in timing and accuracy of reference calibration measurements on CGM device output were assessed