26 research outputs found
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Inventory Data Package for Hanford Assessments
This document presents the basis for a compilation of inventory for radioactive contaminants of interest by year for all potentially impactive waste sites on the Hanford Site for which inventory data exist in records or could be reasonably estimated. This document also includes discussions of the historical, current, and reasonably foreseeable (1944 to 2070) future radioactive waste and waste sites; the inventories of radionuclides that may have a potential for environmental impacts; a description of the method(s) for estimating inventories where records are inadequate; a description of the screening method(s) used to select those sites and contaminants that might make a substantial contribution to impacts; a listing of the remedial actions and their completion dates for waste sites; and tables showing the best estimate inventories available for Hanford assessments
Algorithmic Complexity for Short Binary Strings Applied to Psychology: A Primer
Since human randomness production has been studied and widely used to assess
executive functions (especially inhibition), many measures have been suggested
to assess the degree to which a sequence is random-like. However, each of them
focuses on one feature of randomness, leading authors to have to use multiple
measures. Here we describe and advocate for the use of the accepted universal
measure for randomness based on algorithmic complexity, by means of a novel
previously presented technique using the the definition of algorithmic
probability. A re-analysis of the classical Radio Zenith data in the light of
the proposed measure and methodology is provided as a study case of an
application.Comment: To appear in Behavior Research Method
The neurosurgical benefit of contactless in vivo optical coherence tomography regarding residual tumor detection: A clinical study
PurposeIn brain tumor surgery, it is crucial to achieve complete tumor resection while conserving adjacent noncancerous brain tissue. Several groups have demonstrated that optical coherence tomography (OCT) has the potential of identifying tumorous brain tissue. However, there is little evidence on human in vivo application of this technology, especially regarding applicability and accuracy of residual tumor detection (RTD). In this study, we execute a systematic analysis of a microscope integrated OCT-system for this purpose.Experimental designMultiple 3-dimensional in vivo OCT-scans were taken at protocol-defined sites at the resection edge in 21 brain tumor patients. The system was evaluated for its intraoperative applicability. Tissue biopsies were obtained at these locations, labeled by a neuropathologist and used as ground truth for further analysis. OCT-scans were visually assessed with a qualitative classifier, optical OCT-properties were obtained and two artificial intelligence (AI)-assisted methods were used for automated scan classification. All approaches were investigated for accuracy of RTD and compared to common techniques.ResultsVisual OCT-scan classification correlated well with histopathological findings. Classification with measured OCT image-properties achieved a balanced accuracy of 85%. A neuronal network approach for scan feature recognition achieved 82% and an auto-encoder approach 85% balanced accuracy. Overall applicability showed need for improvement.ConclusionContactless in vivo OCT scanning has shown to achieve high values of accuracy for RTD, supporting what has well been described for ex vivo OCT brain tumor scanning, complementing current intraoperative techniques and even exceeding them in accuracy, while not yet in applicability
Silhouette-based markerless motion estimation of awake rodents in PET
The ability to image the brain of a freely moving rodent using motion-compensated PET presents many exciting possibilities for exploring the links between brain function and behavior. Markerless optical approaches for pose estimation have several potential advantages over marker-based methods: improved accuracy and increased range of detectable motion; no `decoupling' of marker and head motion; and no acclimatization of the animals to attached markers. Our aim in this work was to describe and validate a silhouette-based multi-camera method for estimating the pose of a rat. Random-walk and K-means clustering approaches were very adaptable to uneven lighting and generally provided excellent object segmentations. In obtaining a high quality rat model, shape-from-silhouette and laser scanning both resulted in useful models; laser scanning provided sub-millimeter resolution with very few artifacts and was the method of choice. In our experimental validation, the 3D-2D (model-silhouette) optimization clearly converged to sub-degree and sub-millimeter alignment of the measured and estimated silhouettes. The average discrepancy between test points transformed using the estimated versus ground-truth poses was 0.94 mm ± 0.51 mm. This investigation focused on rigid motion of a rat phantom as a proof-of-principle of the technique. Future work will focus on investigating the potential of designing a non-rigid rodent body model in order to apply the method to a freely moving animal during PET imaging
Silhouette-Based Markerless Motion Estimation of Awake Rodents in PET
The ability to image the brain of a freely moving rodent using motion-compensated PET presents many exciting possibilities for exploring the links between brain function and behavior. Markerless optical approaches for pose estimation have several potential advantages over marker-based methods: improved accuracy and increased range of detectable motion; no 'decoupling' of marker and head motion; and no acclimatization of the animals to attached markers. Our aim in this work was to describe and validate a silhouette-based multi-camera method for estimating the pose of a rat. Random-walk and K-means clustering approaches were very adaptable to uneven lighting and generally provided excellent object segmentations. In obtaining a high quality rat model, shape-from-silhouette and laser scanning both resulted in useful models; laser scanning provided sub-millimeter resolution with very few artifacts and was the method of choice. In our experimental validation, the 3D-2D (model-silhouette) optimization clearly converged to sub-degree and sub-millimeter alignment of the measured and estimated silhouettes. The average discrepancy between test points transformed using the estimated versus ground-truth poses was 0.94 mm ± 0.51 mm. This investigation focused on rigid motion of a rat phantom as a proof-of-principle of the technique. Future work will focus on investigating the potential of designing a non-rigid rodent body model in order to apply the method to a freely moving animal during PET imaging
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GENII Version 2 Software Design Document
This document describes the architectural design for the GENII-V2 software package. This document defines details of the overall structure of the software, the major software components, their data file interfaces, and specific mathematical models to be used. The design represents a translation of the requirements into a description of the software structure, software components, interfaces, and necessary data. The design focuses on the major components and data communication links that are key to the implementation of the software within the operating framework. The purpose of the GENII-V2 software package is to provide the capability to perform dose and risk assessments of environmental releases of radionuclides. The software also has the capability of calculating environmental accumulation and radiation doses from surface water, groundwater, and soil (buried waste) media when an input concentration of radionuclide in these media is provided. This report represents a detailed description of the capabilities of the software product with exact specifications of mathematical models that form the basis for the software implementation and testing efforts. This report also presents a detailed description of the overall structure of the software package, details of main components (implemented in the current phase of work), details of data communication files, and content of basic output reports. The GENII system includes the capabilities for calculating radiation doses following chronic and acute releases. Radionuclide transport via air, water, or biological activity may be considered. Air transport options include both puff and plume models, each allow use of an effective stack height or calculation of plume rise from buoyant or momentum effects (or both). Building wake effects can be included in acute atmospheric release scenarios. The code provides risk estimates for health effects to individuals or populations; these can be obtained using the code by applying appropriate risk factors to the effective dose equivalent or organ dose. In addition, Version 2 uses cancer risk factors from Federal Guidance Report 13 to estimate risk to specific organs or tissues
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Addendum to Composite Analysis for Low-Level Waste Disposal in the 200 Area Plateau of the Hanford Site
This report summarizes efforts to complete an addendum analysis to the first iteration of the Composite Analysis for Low-Level Waste Disposal in the 200 Area Plateau of the Hanford Site (Composite Analysis). This document describes the background and performance objectives of the Composite Analysis and this addendum analysis. The methods used, results, and conclusions for this Addendum analysis are summarized, and recommendations are made for work to be undertaken in anticipation of a second analysis