Accelerating Neutron Tomography experiments through Artificial Neural Network based reconstruction

Neutron Tomography (NT) is a non-destructive technique to investigate the inner structure of a wide range of objects and, in some cases, provides valuable results in comparison to the more common X-ray imaging techniques. However, NT is time consuming and scanning a set of similar objects during a beamtime leads to data redundancy and long acquisition times. Nowadays NT is unfeasible for quality checking study of large quantities of similar objects. One way to decrease the total scan time is to reduce the number of projections. Analytical reconstruction methods are very fast but under this condition generate streaking artifacts in the reconstructed images. Iterative algorithms generally provide better reconstruction for limited data problems, but at the expense of longer reconstruction time. In this study, we propose the recently introduced Neural Network Filtered Back-Projection (NN-FBP) method to optimize the time usage in NT experiments. Simulated and real neutron data were used to assess the performance of the NN-FBP method as a function of the number of projections. For the first time a machine learning based algorithm is applied and tested for NT image reconstruction problem. We demonstrate that the NN-FBP method can reliably reduce acquisition and reconstruction times and it outperforms conventional reconstruction methods used in NT, providing high image quality for limited datasets

The development of the tramway infrastructure in Poland during accession to the European Union

Rozkwit transportu tramwajowego w wielu miastach Europy w ostatnich latach wiąże się z polityką transportową przyjętą przez Unię Europejską w zakresie wspierania elektrycznego transportu miejskiego. Nowoczesny, szybki i wygodny transport tramwajowy może stać się alternatywą dla transportu samochodowego i wpłynąć na zmianę preferencji podróżnych oraz wizerunek śródmieść. W Polsce w ostatnich 10 latach (od przystąpienia Polski do Unii Europejskiej w 2004 r. do końca drugiego okresu budżetowego w 2013 r., w którym Polska partycypowała) funkcjonowało 14 systemów transportu tramwajowego. W większości prowadzono projekty dofinansowane z budżetu unijnego. Wyjątek stanowił Gorzów Wielkopolski, w którym nie wykorzystano szansy na modernizację zdegradowanej infrastruktury, a wręcz rozważano likwidację transportu tramwajowego. Na drugim biegunie polityk transportowych znalazł się Olsztyn, w którym władze lokalne podjęły decyzję o budowie od podstaw nowego systemu tramwajowego. Tramwaje wrócą do Olsztyna po 50 latach od likwidacji pierwszego systemu w 1965 r. Ważnym czynnikiem wpływającym na wykonanie wielu projektów w zakresie infrastruktury tramwajowej była organizacja Mistrzostw Europy w Piłce Nożnej w 2012 r. Cztery miasta, które były współgospodarzami zawodów sportowych, Gdańsk, Poznań, Warszawa i Wrocław, otrzymały specjalną pulę środków, ułatwiającą realizację najważniejszych zadań przed rozpoczęciem mistrzostw. Polityka transportowa Polski zakłada wspieranie miejskiego transportu elektrycznego, w tym transportu tramwajowego, jako przyjaznego środowisku, nieemisyjnego w miejscu eksploatacji i cichego. Członkostwo Polski w Unii Europejskiej umożliwiło modernizację i rozwój systemów tramwajowych dzięki puli środków przeznaczonych na transport.The developing of tramway transport in many European cities In recent years associated with the transport policy adopted by the European Union in supporting urban electric transport. Modern, fast and convenient tramway transport could be an alternative for car transport and alter travelers their preferences and the image of city centers. In Poland in the last 10 years (since Polish accession to the European Union in 2004 to the end of the second budgetary period in 2013 in which Poland participated) functioned fourteen tramway transport systems. For the most part were carried out projects funded from the EU budget. The exception was Gorzów Wielkopolski, in which chance for the modernization of infrastructure degraded bas not been used and even contemplated liquidation of tramways. To the opposition of the transport policles was Olsztyn, in which local authorities have decided to build a new tram system. Tramways return to Olsztyn after 50 years from the liquidation of the first system in 1965. An important factor in the execution of many projects in the field of tramway infrastructure was the organization of the UEFA European Football Championship in 2012. Four cities, which were cohosted a sporting event, Gdańsk, Poznań, Warsaw and Wrocław, received a special pool of funds to facilitate the implementation of the most important tasks before the start of the championship. Polish transport policy intends to promote urban electric transport, including tramways, as an environmentally friendly, non-emission in place and silent operation. Polish membership in the European Union enabled the modernization and development of tramway systems through a pool of funds allocated for transportation. Most cities with tramway transport took advantage of this opportunity and plans further investments

Abstract A Hybrid GPU-CPU Renderer

In this paper we present a hybrid rendering approach that generates fast real time images of a scene by the GPU and then progressively improves quality by selective ray tracing. The GPU solution is used to guide the ray tracing towards error prone areas. We describe the interplay between these two passes for the generation of high quality hard and soft shadows, anti-aliasing, and reflections and refractions. We present a first implementation and discuss its results.

¹²⁵Te Mössbauer spectra of the intercalation compound (Te₂)₂(I₂)

The quadrupole split asymmetric 125Te Mössbauer spectrum recorded from the compound (Te2)2(I2), in which monomolecular planar layers of iodine molecules are intercalated between layers of tellurium, is a reflection of the distorted environment of tellurium atoms in a two-dimensional layered compound in which the elongated flat crystals are preferentially orientated. The differences between the Mössbauer parameters recorded from (Te2)2(I2) and those recorded from elemental tellurium and the tellurium(0) species in the compound Te3Cl2 are associated with small differences between the environments of tellurium in the three compounds. The Mössbauer spectra recorded from (Te2)2(I2) are consistent with a recently proposed model on which the electronic band structure of (Te2)2(I2) has been derived