3,313 research outputs found
2D Time-frequency interference modelling using stochastic geometry for performance evaluation in Low-Power Wide-Area Networks
In wireless networks, interferences between trans- missions are modelled
either in time or frequency domain. In this article, we jointly analyze
interferences in the time- frequency domain using a stochastic geometry model
assuming the total time-frequency resources to be a two-dimensional plane and
transmissions from Internet of Things (IoT) devices time- frequency patterns on
this plane. To evaluate the interference, we quantify the overlap between the
information packets: provided that the overlap is not too strong, the packets
are not necessarily lost due to capture effect. This flexible model can be used
for multiple medium access scenarios and is especially adapted to the random
time-frequency access schemes used in Low-Power Wide-Area Networks (LPWANs). By
characterizing the outage probability and throughput, our approach permits to
evaluate the performance of two representative LPWA technologies
Sigfox{\textsuperscript \textregistered} and LoRaWA{\textsuperscript
\textregistered}
An Automated Treatment Plan Quality Control Tool for Intensity-Modulated Radiation Therapy Using a Voxel-Weighting Factor-Based Re-Optimization Algorithm.
Intensity-modulated radiation therapy (IMRT) currently plays an important role in radiotherapy, but its treatment plan quality can vary significantly among institutions and planners. Treatment plan quality control (QC) is a necessary component for individual clinics to ensure that patients receive treatments with high therapeutic gain ratios. The voxel-weighting factor-based plan re-optimization mechanism has been proved able to explore a larger Pareto surface (solution domain) and therefore increase the possibility of finding an optimal treatment plan. In this study, we incorporated additional modules into an in-house developed voxel weighting factor-based re-optimization algorithm, which was enhanced as a highly automated and accurate IMRT plan QC tool (TPS-QC tool). After importing an under-assessment plan, the TPS-QC tool was able to generate a QC report within 2 minutes. This QC report contains the plan quality determination as well as information supporting the determination. Finally, the IMRT plan quality can be controlled by approving quality-passed plans and replacing quality-failed plans using the TPS-QC tool. The feasibility and accuracy of the proposed TPS-QC tool were evaluated using 25 clinically approved cervical cancer patient IMRT plans and 5 manually created poor-quality IMRT plans. The results showed high consistency between the QC report quality determinations and the actual plan quality. In the 25 clinically approved cases that the TPS-QC tool identified as passed, a greater difference could be observed for dosimetric endpoints for organs at risk (OAR) than for planning target volume (PTV), implying that better dose sparing could be achieved in OAR than in PTV. In addition, the dose-volume histogram (DVH) curves of the TPS-QC tool re-optimized plans satisfied the dosimetric criteria more frequently than did the under-assessment plans. In addition, the criteria for unsatisfied dosimetric endpoints in the 5 poor-quality plans could typically be satisfied when the TPS-QC tool generated re-optimized plans without sacrificing other dosimetric endpoints. In addition to its feasibility and accuracy, the proposed TPS-QC tool is also user-friendly and easy to operate, both of which are necessary characteristics for clinical use
Recursive Hardware-as-a-Service (rHaaS) and Fast Provisioning
Hardware as a Service (HaaS) is a new service being developed by the Massachusetts Open Cloud (MOC) to allow physical servers to be allocated to clients in the same way that virtual servers are in existing IaaS clouds.
This poster describes the new recursive HaaS project and the fast provisioning customization we are developing. Recursive HaaS allows a HaaS service to be layered on top of an existing one. It will allow testing of new features at performance and scale without affecting the production service. It will also allow clients to host their own HaaS on top of a base HaaS to provide, potentially customized, services to their users.
An example customization we are developing is a fast provisioning service that can be used between tenants that have some degree of trust in each other. It will allow nodes to be moved between customers (and a service installed) in seconds, rather than the minutes required by base HaaS
The roles of Eu during the growth of eutectic Si in Al-Si alloys
Controlling the growth of eutectic Si and thereby modifying the eutectic Si from flake-like to fibrous is a key factor in improving the properties of Al-Si alloys. To date, it is generally accepted that the impurity-induced twinning (IIT) mechanism and the twin plane re-entrant edge (TPRE) mechanism as well as poisoning of the TPRE mechanism are valid under certain conditions. However, IIT, TPRE or poisoning of the TPRE mechanism cannot be used to interpret all observations. Here, we report an atomic-scale experimental and theoretical investigation on the roles of Eu during the growth of eutectic Si in Al-Si alloys. Both experimental and theoretical investigations reveal three different roles: (i) the adsorption at the intersection of Si facets, inducing IIT mechanism, (ii) the adsorption at the twin plane re-entrant edge, inducing TPRE mechanism or poisoning of the TPRE mechanism, and (iii) the segregation ahead of the growing Si twins, inducing a solute entrainment within eutectic Si. This investigation not only demonstrates a direct experimental support to the well-accepted poisoning of the TPRE and IIT mechanisms, but also provides a full picture about the roles of Eu atoms during the growth of eutectic Si, including the solute entrainment within eutectic Si
Quantum mutual information of an entangled state propagating through a fast-light medium
Although it is widely accepted that classical information cannot travel
faster than the speed of light in vacuum, the behavior of quantum correlations
and quantum information propagating through actively-pumped fast-light media
has not been studied in detail. To investigate this behavior, we send one half
of an entangled state of light through a gain-assisted fast-light medium and
detect the remaining quantum correlations. We show that the quantum
correlations can be advanced by a small fraction of the correlation time while
the entanglement is preserved even in the presence of noise added by
phase-insensitive gain. Additionally, although we observe an advance of the
peak of the quantum mutual information between the modes, we find that the
degradation of the mutual information due to the added noise appears to prevent
an advancement of the leading edge. In contrast, we show that both the leading
and trailing edges of the mutual information in a slow-light system can be
significantly delayed
IVD Delivery System
Cepheid is a molecular diagnostics company that has assigned our senior project team to design a system that automates the current manual transportation of samples between two laboratory rooms. With the focus of retaining the sanitary integrity of both the samples as well as the initial cleanroom, also referred to as the packaging laboratory, our team has designed an extension of the current passthrough that will contain all other subsystems. In order to automate the transportation of the samples, the design employs a track and trolley system to be purchased and mounted within the passthrough. A verification prototype was built and tested to ensure the design would work as intended, modeling a five-foot section of the entire sixty-foot path. This prototype features an interlocking system to eliminate any potential for backflow between lab rooms. Samples are carried in a hanging bag that the team has designed to not spill any of the cartridge’s contents. Additionally, a virtual model was made and used to perform varying load tests to prove the validity of the materials selected for the passthrough. While effective, the proposed design could be improved in efficiency, though regardless of the decisions made by Cepheid regarding implementation, the designed passthrough extension and interlocking system could be used in any industry backflow prevention scenario
Collaborative Bimanual Manipulation Using Optimal Motion Adaptation and Interaction Control Retargetting Human Commands to Feasible Robot Control References
This article presents a robust and reliable human–robot collaboration (HRC) framework for bimanual manipulation. We propose an optimal motion adaptation method to retarget arbitrary human commands to feasible robot pose references while maintaining payload stability. The framework comprises three modules: 1) a task-space sequential equilibrium and inverse kinematics optimization ( task-space SEIKO ) for retargeting human commands and enforcing feasibility constraints, 2) an admittance controller to facilitate compliant human–robot physical interactions, and 3) a low-level controller improving stability during physical interactions. Experimental results show that the proposed framework successfully adapted infeasible and dangerous human commands into continuous motions within safe boundaries and achieved stable grasping and maneuvering of large and heavy objects on a real dual-arm robot via teleoperation and physical interaction. Furthermore, the framework demonstrated the capability in the assembly task of building blocks and the insertion task of industrial power connectors
Introduction to General Psychology (Augusta)
This Grants Collection for Introduction to General Psychology was created under a Round Five ALG Textbook Transformation Grant.
Affordable Learning Georgia Grants Collections are intended to provide faculty with the frameworks to quickly implement or revise the same materials as a Textbook Transformation Grants team, along with the aims and lessons learned from project teams during the implementation process.
Documents are in .pdf format, with a separate .docx (Word) version available for download. Each collection contains the following materials: Linked Syllabus Initial Proposal Final Reporthttps://oer.galileo.usg.edu/psychology-collections/1017/thumbnail.jp
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