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Reconstruction of high-resolution 3D dose from matrix measurements: error detection capability of the COMPASS correction kernel method

The COMPASS system (IBADosimetry) is a quality assurance (QA) tool whichreconstructs 3D doses inside a phantom or a patient CT. The dose is predictedaccording to the RT plan with a correction derived from 2D measurementsof a matrix detector. This correction method is necessary since a directreconstruction of the fluence with a high resolution is not possible becauseof the limited resolution of the matrix used, but it comes with a blurring of thedosewhich creates inaccuracies in the dose reconstruction. This paper describesthe method and verifies its capability to detect errors in the positioning of aMLC with 10 mm leaf width in a phantom geometry. Dose reconstruction wasperformed forMLC position errors of various sizes at various locations for bothrectangular and intensity-modulated radiotherapy (IMRT) fields and comparedto a reference dose. It was found that the accuracy with which an error inMLCposition is detected depends on the location of the error relative to the detectorsin the matrix. The reconstructed dose in an individual rectangular field for leafpositioning errors up to 5 mm was correct within 5% in 50% of the locations.At the remaining locations, the reconstruction of leaf position errors larger than3 mm can show inaccuracies, even though these errors were detectable in thedose reconstruction. Errors larger than 9 mm created inaccuracies up to 17% ina small area close to the penumbra. The QA capability of the system was testedthrough gamma evaluation. Our results indicate that themean gamma providedby the system is slightly increased and that the number of points above gamma 1ensures error detection for QA purposes. Overall, the correction kernel methodused by the COMPASS system is adequate to perform QA of IMRT treatmentplans with a regular MLC, despite local inaccuracies in the dose reconstruction.

Quantification of damage evolution in masonry walls subjected to induced seismicity

This paper aims to quantify the evolution of damage in masonry walls under induced seismicity. A damage index equation, which is a function of the evolution of shear slippage and opening of the mortar joints, as well as of the drift ratio of masonry walls, was proposed herein. Initially, a dataset of experimental tests from in-plane quasi-static and cyclic tests on masonry walls was considered. The experimentally obtained crack patterns were investigated and their correlation with damage propagation was studied. Using a software based on the Distinct Element Method, a numerical model was developed and validated against full-scale experimental tests obtained from the literature. Wall panels representing common typologies of house façades of unreinforced masonry buildings in Northern Europe i.e. near the Groningen gas field in the Netherlands, were numerically investigated. The accumulated damage within the seismic response of the masonry walls was investigated by means of representative harmonic load excitations and an incremental dynamic analysis based on induced seismicity records from Groningen region. The ability of this index to capture different damage situations is demonstrated. The proposed methodology could also be applied to quantify damage and accumulation in masonry during strong earthquakes and aftershocks too.

Effects of urban green infrastructure (UGI) on local outdoor microclimate during the growing season

Making sense of the data

Charging an electric vehicle needs to be as simple as possible for the user. He needs to park his car, plug his vehicle and identify to start charging. There is no need to understand the technology and protocols needed to reach this simple task.For the students and researchers of the Amsterdam University of Applied Science (AUAS / HvA), there is a need to understand as deep as possible all the techniques involved in this technology.The purpose of this document is to give to the reader the information he needs to understand how an electric car can be charged and how he can use these knowledges to analyses and interpret data.

Operation, maintenance and rehabilitation techniques

A systematic operation, maintenance, and rehabilitation program is an essential element in the management of a wastewater collection system. Effective inspection, cleaning, and rehabilitation are key processes for optimizing the proper functioning of a collection system. 7-1 7.1 Methods and Equipment The following information outlines the methods and equipment frequently utilized to inspect and clean gravity collection systems and pumping stations. Frequent inspection and cleaning is essential for normal functioning and problem identification. Information is also presented regarding spare parts and equipment necessary for effective operation. 7.1.1 Gravity Collection Systems Physical Inspection A physical inspection is vital to an O&M program. Without it, a maintenance program cannot be implemented in a systematic way since system problems cannot be quantified. Elements of a physical inspection program include visual and equipment-based techniques that use established industry methods of system evaluation. Physical inspections should be performed on a regularly scheduled basis as a part of the preventive maintenance program. The purpose of conducting inspections is to: • Identify what is in the system (inventory). • Identify the location of the system's components. • Determine the condition of the components (assessment). • Prevent problems from developing. Before acceptance of a newly constructed collection system, O&M personnel should conduct a physical inspection to verify the accuracy and completeness of the record drawings. Inspection before acceptance will also ensure that the new components are clear of construction debris and rocks.

Vehicle4 Energy Services (V4ES) evaluation for upscaling and transnational potential

This report is intended to collect, present, and evaluate the various solutions applied in individual operational pilots for their (upscaling and transnational transfer) potential, in terms of opportunities and barriers, over the short and long(er)-term. This is done by identifying the main characteristics of the solutions and sites and the relevant influencing factors at different local (dimension) contexts.The analysis provides insights in barriers but also opportunities and conditions for success across four main dimensions that make up the local context landscape. We consider two main roll-out scenarios:1. Upscaling within the boundaries of the country where the operational pilot (OP) took place2. Transnational Transfer relates to the potential for transferring a (V4)ES solution to any of the other three (project) countriesThere are several aspects within the four main dimensions that are cross-cutting for all four countries, either because EU legislation lies at its roots, or because market conditions are fairly similar for certain influencing factors in those dimension.Ultimately, both Smart Charging and V2X market are still in their relevant infancies. The solutions applied in various SEEV4-City pilots are relatively straightforward and simple in ‘smartness’. This helps the potential for adoption but may not always be the optimal solution yet. The Peak shaving or load/demand shifting solutions are viable options to reduce costs for different stakeholders in the (electricity) supply chain. The market is likely to mature and become much smarter in coming 5 – 10 years. This also includes the evolvement (or spin-offs) of the solutions applied in SEEV4-_City as well. At least in the coming (approximately) 5 years Smart Charging appears to have the better financial business case and potential for large scale roll-out with less (impactful) bottlenecks, but looking at longer term V2X holds its potential to play a significant role in the energy transition.A common denominator as primary barriers relates to existing regulation, standards readiness and limited market availability of either hardware or service offerings.