The Effect of Print Angulation on the Accuracy and Precision of 3D-Printed Orthodontic Retainers

Purpose: The aims of this study were: 1) to compare the accuracy and precision of 3- dimensional (3D) printed retainers at various angulations, 2) to evaluate the effect of angulation on printing time and the amount of resin consumed. Methods: Using a stereolithography (SLA) 3D printer, a total of 60 clear retainers were printed at five angulations (n=12, each): 15, 30, 45, 60, and 90 degrees. Six retainers were printed each cycle at a random order for all print angulations as print 1 and print 2. Digital images of the original and printed retainers were superimposed. Discrepancies on eight landmarks were measured by two independent examiners. 0.25 mm was set as the clinically acceptable threshold to determine the accuracy of the retainers. Results: Deviations ranged from 0.074 mm to 0.225 mm from the reference retainer at the cusp tips and incisal edges at all angulations, falling within the threshold of clinical acceptance. Smooth surfaces ranged from 0.263 mm to 0.480 mm, falling beyond the level of clinical acceptance. Printing at 15 degrees was estimated to be the most time-efficient, while printing at 45 degrees was estimated to be the most cost-effective. Conclusions: 3D-printed retainers, using an SLA printer, were found to be accurate within 0.25 mm at all print angulations at the cusp tips and incisal edges when compared to the reference digital file. Smooth facial surfaces fell beyond of the level of clinical acceptability. Printing at 15 degrees was estimated to be the most time-efficient, while printing at 45 degrees was estimated to be the most cost-effective

VM-MAD: a cloud/cluster software for service-oriented academic environments

The availability of powerful computing hardware in IaaS clouds makes cloud computing attractive also for computational workloads that were up to now almost exclusively run on HPC clusters. In this paper we present the VM-MAD Orchestrator software: an open source framework for cloudbursting Linux-based HPC clusters into IaaS clouds but also computational grids. The Orchestrator is completely modular, allowing flexible configurations of cloudbursting policies. It can be used with any batch system or cloud infrastructure, dynamically extending the cluster when needed. A distinctive feature of our framework is that the policies can be tested and tuned in a simulation mode based on historical or synthetic cluster accounting data. In the paper we also describe how the VM-MAD Orchestrator was used in a production environment at the FGCZ to speed up the analysis of mass spectrometry-based protein data by cloudbursting to the Amazon EC2. The advantages of this hybrid system are shown with a large evaluation run using about hundred large EC2 nodes.Comment: 16 pages, 5 figures. Accepted at the International Supercomputing Conference ISC13, June 17--20 Leipzig, German

Reproducible Software Appliances for Experimentation

International audienceExperiment reproducibility is a milestone of the scientific method. Reproducibility of experiments in computer science would bring several advantages such as code re-usability and technology transfer. The reproducibility problem in computer science has been solved partially, addressing particular class of applications or single machine setups. In this paper we present our approach oriented to setup complex environments for experimentation, environments that require a lot of configuration and the installation of several software packages. The main objective of our approach is to enable the exact and independent reconstruction of a given software environment and the reuse of code. We present a simple and small software appliance generator that helps an experimenter to construct a specific software stack that can be deployed on different available testbeds

CleanTX Analysis on the Smart Grid

The utility industry in the United States has an opportunity to revolutionize its electric grid system by utilizing emerging software, hardware and wireless technologies and renewable energy sources. As electricity generation in the U.S. increases by over 30% from today’s generation of 4,100 Terawatt hours per year to a production of 5,400 Terawatt hours per year by 2030, a new type of grid is necessary to ensure reliable and quality power. The projected U.S. population increase and economic growth will require a grid that can transmit and distribute significantly more power than it does today. Known as a Smart Grid, this system enables two- way transmission of electrons and information to create a demand-response system that will optimize electricity delivery to consumers. This paper outlines the issues with the current grid infrastructure, discusses the economic advantages of the Smart Grid for both consumers and utilities, and examines the emerging technologies that will enable cleaner, more efficient and cost- effective power transmission and consumption.IC2 Institut