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We present SuperConga, an open-source framework for simulating equilibrium properties of unconventional and ballistic singlet superconductors, confined to two-dimensional (2D) mesoscopic grains in a perpendicular external magnetic field, at arbitrary low temperatures. It aims at being both fast and easy to use, enabling research without access to a computer cluster, and visualization in real-time with OpenGL. The core is written in C++ and CUDA, exploiting the embarrassingly parallel nature of the quasiclassical theory of superconductivity by utilizing the parallel computational power of modern graphics processing units. The framework self-consistently computes both the superconducting order-parameter and the induced vector potential and finds the current density, free energy, induced flux density, local density of states (LDOS), and the magnetic moment. A user-friendly Python frontend is provided, enabling simulation parameters to be defined via intuitive configuration files, or via the command-line interface, without requiring a deep understanding of implementation details. For example, complicated geometries can be created with relative ease. The framework ships with simple tools for analyzing and visualizing the results, including an interactive plotter for spectroscopy. An overview of the theory is presented, as well as examples showcasing the framework's capabilities and ease of use. The framework is free to download from , which also links to the extensive user manual, containing even more examples, tutorials, and guides. To demonstrate and benchmark SuperConga, we study the magnetostatics, thermodynamics, and spectroscopy of various phenomena. In particular, we study flux quantization in solenoids, vortex physics, surface Andreev bound-states, and a "phase crystal." We compare our numeric results with analytics and present experimental observables, e.g., the magnetic moment and LDOS, measurable with, for example, scanning probes, STM, and magnetometry.

Community microgrids implemented in existing electricity grids can meet both development targets set out in the Paris agreement: 1. mitigate greenhouse gas emissions through increased implementation of renewable energy sources, and 2. to adapt to climate related disturbances and risk of catastrophes. Community microgrids are, however, complex to implement and institutional change is needed to reach their full potential. The purpose of this article is to review existing literature and analyze institutional developments influencing the growth of community microgrids. The literature describes a concentration of microgrid activities in specific regions: USA, EU, Asia and Australia. Varying reasons for implementing community microgrids were found in the different regions but similar institutional developments occurred, albeit with differing emphasis due to contextual specificities. Formal directions do however influence informal institutions even though their aims differ. Power utilities stand out as a critical actor and both formal and informal institutions put pressure on utilities to update their traditional business models. This article illustrates how informal and formal institutions play a significant role in the growth of community microgrids in existing electricity grids and provide interesting examples which can be utilized by policymakers. Microgrid development is still in a formative phase and further institutional change in the form of updated regulations is needed.

BACKGROUND: Stress problems are major public health problems. OBJECTIVE: To gain an increased understanding of howworking men seeking care due to minor metal dysfunctions related to stress recognize their symptoms, what triggers them, and how this impacts their everyday life. PARTICIPANTS: Fourteen men of working age, consecutively seeking care due to minor mental dysfunctions indicating stress problems, at two clinics in the Stockholm area in Sweden during 2009 and 2010. METHODS: A qualitative methodology was chosen, and interviews were performed and analyzed using qualitative content analysis. RESULTS: In the manifest content, categories such as difficulties in setting limits, low socialsupport, high work demands, and mental and physical dysfunctions were identified. Three themes finally emerged (latent content) and indicated that in this group of informants there are stressors both within the individual himself, in working life, and a lack of recovery. CONCLUSIONS: Based on our findings it would be possible to implement measures to prevent stress-related problems by promoting coping strategies on an individual level, encouraging social networks, and regular physical exercise. By implementing work policies and workplace modifications, and also providing individual support at the workplace, supervisors and human resources managers could prevent, or modify stress problems among employees.

Part of urn:nbn:se:su:diva-7458

Purpose: The aim of the present study is to compare two different methods for evaluation of the quality of clinical X-ray images. Methods: Based on fifteen lumbar spine radiographs, two new sets of images were created. A hybrid image set was created by adding two distributions of artificial lesions to each original image. The image quality parameters spatial resolution and noise were manipulated and a total of 210 hybrid images were created. A set of 105 disease-free images was created by applying the same combinations of spatial resolution and noise to the original images. The hybrid images were evaluated with the free-response forced error experiment (FFE) and the normal images with visual grading analysis (VGA) by nine experienced radiologists. Results: In the VGA study, images with low noise were preferred over images with higher noise levels. The alteration of the MTF had a limited influence on the VGA score. For the FFE study, the visibility of the lesions was independent of the sharpness and the noise level. No correlation was found between the two image quality measures. Conclusions: FFE is a precise method for evaluation of image quality, but the results are only valid for the type of lesion used in the study, whereas VGA is a more general method for clinical image quality assessment. The results of the FFE study indicate that there might be a potential to lower the dose levels in lumbar spine radiography without losing important diagnostic information. © The Author 2005. Published by Oxford University Press. All rights reserved.

Purpose: To investigate the influence of masking on the inter-observer variation in image quality evaluation of clinical radiographs of chest and lumbar spine. Background: Inter-observer variation is a big problem in image quality evaluation since this variation is often much bigger than the variation in image quality between, for example, two radiographic systems. In this study, we have evaluated the effect of masking on the inter-observer variation. The idea of the masking was to force every observer to view exactly the same part of the image and to avoid the effect of the overall 'first impression' of the image. A discussion with a group of European expert radiologists before the study indicated that masking might be a good way to reduce the inter-observer variation. Methods: Five chest and five lumbar spine radiographs were collected together with detailed information regarding exposure conditions. The radiographs were digitised with a high-performance scanner and five different manipulations were performed, simulating five different exposure conditions. The contrast, noise and spatial resolution were manipulated by this method. The images were printed onto the film and the individual masks were produced for each film, showing only the parts of the images that were necessary for the image quality evaluation. The quality of the images was evaluated on ordinary viewing boxes by a large group of experienced radiologists. The images were examined with and without the masks with a set of image criteria (if fulfilled, 1 point, and not fulfilled, 0 point), and the mean score was calculated for each simulated exposure condition. Results: The results of this study indicate that - contrary to what was supposed - the inter-observer variation increased when the images were masked. In some cases, especially for chest, this increase was statistically significant. Conclusions: Based on the results of this study, image masking in studies of fulfilment of image criteria cannot b

Most detection studies in chest radiography treat the entire chest image as a single background or divided into the two regions parenchyma and mediastinum. However, the different parts of the lung show great variations in attenuation and structure, leading to different amounts of quantum noise and scattered radiation as well as different complexity. Detailed data on the difference in detectability in the different regions are of importance. The purpose of this study was to quantify the difference in detectability between different regions of a chest image. The chest X ray was divided into six different regions, where each region was considered to be uniform in terms of detectability. Thirty clinical chest images were collected and divided into the different regions. Simulated designer nodules with a full-width-at-fifth-maximum of 10 mm but with varying contrast were added to the images. An equal number of images lacking pathology were included and a receiver operating characteristic (ROC) study was conducted with five observers. Results show that the image contrast needed to obtain a constant value of Az (area under an ROC curve) differs by more than a factor of four between different regions. © The Author 2005. Published by Oxford University Press. All rights reserved.

Part of urn:nbn:se:su:diva-7458