5,077 research outputs found
Teachers as Theorists
This paper addresses the tensions that exist between policy-makers and practitioners about what learning and teaching should really be about. It adds to the collective reflection on what learning is about and how we should never stop engaging in reflection about it in an active, revolving and changing manner. Similarities between second language learning and generic learning intersperse the reflective account as the author looks through the lenses of her own disciplines of Linguistics and English as a Second Language. The reflection digs deep into the emotions of a critical pedagogue and is finally channelled into a âpedagogy of hopeâ for a better future
Self-injective algebras and the second Hochschild cohomology group
In this paper we study the second Hochschild cohomology group
of a finite dimensional algebra . In particular, we
determine where is a finite dimensional
self-injective algebra of finite representation type over an algebraically
closed field and show that this group is zero for most such ; we
give a basis for in the few cases where it is not zero.Comment: Corrections to some calculation
Advancing Human Rights Through the United Nations
Today's high oil prices and more stringent environmental requirements have led to that manufacturers of mobile construction equipment try to make their products more energy efficient. With this in mind a project about hybridization of hydraulic systems has been formed. The purpose of this project was to analyze the savings that can be achieved by hybridization of hydraulic systems. A reach stacker truck (Kalmar DRD450-80S4XS) were simulated in some load cases with conventional hydraulic systems and with three types of hybridized hydraulic systems. Different parts of the hydraulic systems were also analyzed separately. The analysis has shown that significant energy savings can be achieved by hybridizing hydraulic systems. The analysis showed that between 9-30% energy savings could be achieved by hybridizing the truck's various subsystems.Med dagens höga oljepriser och samhÀllets allt strÀngare miljökrav, stÀvar tillverkare av mobila entreprenadmaskiner efter att energieffektivisera sina produkter. Med detta i tanke formades ett projekt om att regenerera hydraulisk energi pÄ entreprenadmaskiner. Syftet med detta projekt var att analysera vilka besparingar som kan Ästakommas genom att hydraulsystemet pÄ entrprenadmaskiner hybridiseras. En reachstacker truck (Kalmar DRD450-80S4XS) simulerades i nÄgra lastfall med konventionellt hydraulsystem samt med tre typer av hybridiserade hydraulsystem. Olika delar av de hydrauliska systemen analyserades Àven var för sig. Analysen har visat att stora energibesparingar kan Ästakommas genom att hybridisera hydraulsystem. Den genomförda analysen visade pÄ att mellan 9-30% energibesparing kunde uppnÄs genom att hybridisera truckens olika delsystem
Fractal analysis of CE CT lung tumours images
AIM The fractal dimension (FD) of a structure provides a measure of its complexity. This pilot study aims to determine FD values for lung cancers visualised on Computed Tomography (CT) and to assess the potential for tumour FD measurements to provide an index of tumour aggression. METHOD Pre-and post-contrast CT images of the thorax acquired from 15 patients with lung cancers of greater than 10mm were transformed to fractal dimension images using a box-counting algorithm at various scales. A region of interest (ROI) was determined covering tumour locations, which were more apparent on FD images as compared to images before processing. The average tumour FD (FDavg) was computed and compared with the intensity average before FD processing. FD values were correlated with 2 markers of tumour aggression: tumour stage and tumour uptake of fluorodeoxyglucose (FDG) as determined by Positron Emission Tomography. RESULTS For pre-contrast images, the tumour FDavg correlated with tumour stage (r = 0.537, p = 0.0387) and FDG uptake (r= 0.64, p< 0.001). FDavg decreased following contrast enhancement for most tumours. CONCLUSION Fractal analysis of CT images of lung tumours could potentially provide additional information about likely tumour aggression and so impact on clinical management decisions and choice of treatment
Texture analysis of aggressive and nonaggressive lung tumor CE CT images
This paper presents the potential for fractal analysis of time sequence contrast-enhanced (CE) computed tomography (CT) images to differentiate between aggressive and nonaggressive malignant lung tumors (i.e., high and low metabolic tumors). The aim is to enhance CT tumor staging prediction accuracy through identifying malignant aggressiveness of lung tumors. As branching of blood vessels can be considered a fractal process, the research examines vascularized tumor regions that exhibit strong fractal characteristics. The analysis is performed after injecting 15 patients with a contrast agent and transforming at least 11 time sequence CE CT images from each patient to the fractal dimension and determining corresponding lacunarity. The fractal texture features were averaged over the tumor region and quantitative classification showed up to 83.3% accuracy in distinction between advanced (aggressive) and early-stage (nonaggressive) malignant tumors. Also, it showed strong correlation with corresponding lung tumor stage and standardized tumor uptake value of fluoro deoxyglucose as determined by positron emission tomography. These results indicate that fractal analysis of time sequence CE CT images of malignant lung tumors could provide additional information about likely tumor aggression that could potentially impact on clinical management decisions in choosing the appropriate treatment procedure
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