336 research outputs found
Determination of Flaw Growth Characteristics of Ti-6Al-4V Sheet in the Solution-Treated and Aged Condition
The specific experimental investigation undertaken was designed to answer these questions on Ti-6Al-4V in the solution treated and aged condition. The defect growth and fracture characteristics were studied in parent (unwelded) and welded sheet material. The results of the study indicate that cryogenic proof testing will screen smaller size defects than proof testing at ambient conditions. However some unusual crack growth behavior during the proof test simulation suggests that some further study be made of stress and time duration effects
An experimental and theoretical investigation of plane-stress fracture of 2024-T351 aluminum alloy
Plane-stress fracture behavior of precracked aluminum alloy
Trends in Competitive Balance: Is There Evidence for Growing Imbalance in Professional Sport Leagues?
Terrorism and the Regional and Religious Risk Perception of Foreigners: The Case of German Tourists
Sports Heroes and Mass Sports Participation – the (Double) Paradox of the 'German Tennis Boom'
Adapting temperature predictions to MR imaging in treatment position to improve simulation-guided hyperthermia for cervical cancer
Hyperthermia treatment consists of elevating the temperature of the tumor to increase the effectiveness of radiotherapy and chemotherapy. Hyperthermia treatment planning (HTP) is an important tool to optimize treatment quality using pre-treatment temperature predictions. The accuracy of these predictions depends on modeling uncertainties such as tissue properties and positioning. In this study, we evaluated if HTP accuracy improves when the patient is imaged inside the applicator at the start of treatment. Because perfusion is a major uncertainty source, the importance of accurate treatment position and anatomy was evaluated using different perfusion values. Volunteers were scanned using MR imaging without (&#x201C;planning setup&#x201D;) and with the MR-compatible hyperthermia device (&#x201C;treatment setup&#x201D;). Temperature-based quality indicators were used to assess the differences between the standard, apparent and the optimized hyperthermia dose. We conclude that pre-treatment imaging can improve HTP predictions accuracy but also, that tissue perfusion modelling is crucial if temperature-based optimization is applied.</p
Better Baltic Sea wave forecasts: improving resolution or introducing ensembles?
The performance of short-range operational forecasts of
significant wave height (SWH) in the Baltic Sea is evaluated. Forecasts produced
by a base configuration are intercompared with forecasts from two improved
configurations: one with improved horizontal and spectral resolution and one
with ensembles representing uncertainties in the physics of the forcing wind
field and the initial conditions of this field. Both of the improved forecast
classes represent an almost equal increase in computational costs. Therefore, the
intercomparison addresses the question of whether more computer
resources would be more favorably spent on enhancing the spatial and spectral
resolution or, alternatively, on introducing ensembles. The intercomparison
is based on comparisons with hourly observations of significant wave height
from seven observation sites in the Baltic Sea during the 3-year period from
2015 to 2017. We conclude that for most wave measurement sites, the
introduction of ensembles enhances the overall performance of the forecasts,
whereas increasing the horizontal and spectral resolution does not. These
sites represent offshore conditions, in that they are well exposed from all directions, are a
large distance from the nearest coast and in deep water. Therefore,
there is the a priori expectation that a detailed shoreline and bathymetry will not have
any impact. Only at one site do we find that increasing the horizontal and
spectral resolution significantly improves the forecasts. This site is
situated in nearshore conditions, close to land and a nearby island, and is
therefore shielded from many directions. Consequently, this study concludes that
to improve wave forecasts in offshore areas, ensembles should be introduced.
For near shore areas, in comparison, the study suggests that additional computational
resources should be used to increase the resolution.</p
The Feel-Good Effect at Mega Sport Events - Recommendations for Public and Private Administration Informed by the Experience of the FIFA World Cup 2006
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