The trace formula and the existence of PEL type Abelian varieties modulo p

We show, using the trace formula, that any Newton stratum of a Shimura variety of PEL-type of types (A) and (C) is non-empty at the primes of good reduction. Furthermore we prove conditionally the non-emptiness for Shimura data associated to odd Spin groups. Our results are conditional on Rapoport-Langlands conjecture and Arthur's conjectures on the discrete spectrum. Both these results have been announced by Arthur and Kisin in significant cases

Semantic systems and visual tools to analyze climate change communication

Given the intense attention that environmental topics such as climate change attract in news and social media coverage, key questions are how different stakeholders perceive observable threats and policy options, how public media react to new scientific insights, and how journalists present climate science knowledge to the public. This presentation will demonstrate the Web intelligence platform [1] to address these questions, including knowledge extraction and visualization techniques to explore the lexical and geospatial context of online coverage. The examples stem from the Media Watch on Climate Change [2], the Climate Resilience Toolkit [3] and the NOAA Media Watch the three applications that aggregate environmental resources from a wide range of online sources. These systems not only show the value of providing comprehensive information to the public, but also have helped to develop novel communication success metrics beyond bipolar assessments of sentiment

The Complexity of Iterated Strategy Elimination

We consider the computational complexity of the question whether a certain strategy can be removed from a game by means of iterated elimination of dominated strategies. In particular, we study the influence of different definitions of domination and of the number of different payoff values. In addition, the consequence of restriction to constant-sum games is shown

Comprehensive investigation of mechanical properties of fused deposition modelling : a dissertation presented in partial fulfilment of the requirements for the degree of Doctor of Philosophy in Engineering at Massey University, Albany, New Zealand

Fused depositing modelling (FDM) is a layer wise manufacturing method whereby parts are printed from the bottom up through the extrusion and deposition of a filament onto a print base. Various test methods exist for the determination of part mechanical properties. These include tensile, flexural, and impact testing and are conducted using a variety of standards including those of ASTM and ISO. Many researchers have investigated the effects of factors such as road width, raster orientation, layer height, and air gap on the mechanical properties of FDM parts. However, there are many unexplored factors that also impact on the properties of printed parts. For example, the printers used in characterisation studies are mostly commercially available or consumer market printers which allow only limited control over the print parameters and print with a limited set of materials. Similarly, the life of the printer can also affect the print quality but this has not been studied before. Control over machines could be achieved by purchasing additional print profiles from the manufacturers or by open-sourcing legacy hardware through retrofitment with new electronics and software. The latter option is more economically viable as there are a large number of decommissioned legacy machines that have superior hardware cheaply/freely available. A retrofitted commercial 3D printer would allow control over print parameters and printing with materials outside the ones sold by the manufacturers. This can open new avenues to study the properties of the printed parts. In this work, a Stratasys Vantage X 3D printer has been retrofitted and made open-source through a combination of hardware, software, and firmware modifications. These modifications result in complete control by the user over all print variables along with the ability to use any feedstock including custom made feed stocks and ones that are locked by the manufacturer. The printing accuracy of the machine is evaluated by optical imaging of the printed samples and destructive testing in accordance with the ASTM D638 standard. . To study the effect of the machine’s life on the properties, a longitudinal study is designed in which two groups of parts (with 0° and 90° orientations) are printed at two different times during the course of this research. The temporal spacing between the parts is eighteen months. The parts are designed according to ASTM D638 standard and printed on identical printers using the same parameters on both occasions. The parts are subjected to tensile testing for the mechanical characterization while scanning electron microscopy (SEM) is used for the examination of the sample’s fracture and topographical surfaces. A difference is discovered between the Young’s moduli of old and new groups. The orthotropic nature of FDM parts becomes prevalent in the strain responses of samples with 0° samples experiencing the largest strain. Distinct differences exist between the diffusion levels of the chronological sample groups, with the original batch exhibiting greater diffusion resulting in almost indistinguishable layers and higher tensile strengths. Individual layers are easily observed in the newer sample groups. Topographical analysis of samples shows up to 0.1mm difference between the road widths with the older samples roads being the narrowest. Results from this research show that the age of the printer affects the mechanical properties of the parts with the older parts exhibiting greater strength compared to their new counterparts even though both were printer under identical conditions. Therefore, a significant difference exists between temporally spaced FDM parts. To conclude, this research has successfully retrofitted an old FDM system which is capable of printing various materials through a choice of user parameters. The longitudinal study conducted to study the effect of the machine age on the printed parts purports that as the printing machines get older their print quality deteriorates and this factor should be considered by designers when designing parts for functional purposes

Corporate social responsibility in the UK, the Netherlands and Germany: theory and forerunners

The results in this paper should help connect theoretical concepts with CSR practices in the current business world. This paper will present the findings of a survey sent to businesses in the UK, the Netherlands, and Germany. The empirical data indicate some interesting tendencies. CSR as perceived within the business community is strongly related to environmental management and has a longer history than might have been expected. External factors, such as legal requirements, general external pressure (NGOs, globalization), and media coverage and campaigning have triggered changes in the business world in favor of CSR, but when CSR policies and schemes are initially under discussion, internal forces, such as the board of directors and the middle management, take over and lead the process. Furthermore, the results of the questionnaire show that external forces, such as government, NGOs, and communities, are not relevant with respect to driving CSR development forward