A Tale Of 160 Scientists, Three Applications, a Workshop, and a Cloud

The NASA Exoplanet Science Institute (NExScI) hosts the annual Sagan Workshops, thematic meetings aimed at introducing researchers to the latest tools and methodologies in exoplanet research. The theme of the Summer 2012 workshop, held from July 23 to July 27 at Caltech, was to explore the use of exoplanet light curves to study planetary system architectures and atmospheres. A major part of the workshop was to use hands-on sessions to instruct attendees in the use of three open source tools for the analysis of light curves, especially from the Kepler mission. Each hands-on session involved the 160 attendees using their laptops to follow step-by-step tutorials given by experts. One of the applications, PyKE, is a suite of Python tools designed to reduce and analyze Kepler light curves; these tools can be invoked from the Unix command line or a GUI in PyRAF. The Transit Analysis Package (TAP) uses Markov Chain Monte Carlo (MCMC) techniques to fit light curves under the Interactive Data Language (IDL) environment, and Transit Timing Variations (TTV) uses IDL tools and Java-based GUIs to confirm and detect exoplanets from timing variations in light curve fitting. Rather than attempt to run these diverse applications on the inevitable wide range of environments on attendees laptops, they were run instead on the Amazon Elastic Cloud 2 (EC2). The cloud offers features ideal for this type of short term need: computing and storage services are made available on demand for as long as needed, and a processing environment can be customized and replicated as needed. The cloud environment included an NFS file server virtual machine (VM), 20 client VMs for use by attendees, and a VM to enable ftp downloads of the attendees' results. The file server was configured with a 1 TB Elastic Block Storage (EBS) volume (network-attached storage mounted as a device) containing the application software and attendees home directories. The clients were configured to mount the applications and home directories from the server via NFS. All VMs were built with CentOS version 5.8. Attendees connected their laptops to one of the client VMs using the Virtual Network Computing (VNC) protocol, which enabled them to interact with a remote desktop GUI during the hands-on sessions. We will describe the mechanisms for handling security, failovers, and licensing of commercial software. In particular, IDL licenses were managed through a server at Caltech, connected to the IDL instances running on Amazon EC2 via a Secure Shell (ssh) tunnel. The system operated flawlessly during the workshop

High-Level Waste Melter Study Report

At the Hanford Site in Richland, Washington, the path to site cleanup involves vitrification of the majority of the wastes that currently reside in large underground tanks. A Joule-heated glass melter is the equipment of choice for vitrifying the high-level fraction of these wastes. Even though this technology has general national and international acceptance, opportunities may exist to improve or change the technology to reduce the enormous cost of accomplishing the mission of site cleanup. Consequently, the U.S. Department of Energy requested the staff of the Tanks Focus Area to review immobilization technologies, waste forms, and modifications to requirements for solidification of the high-level waste fraction at Hanford to determine what aspects could affect cost reductions with reasonable long-term risk. The results of this study are summarized in this report

Policy Advice as an Investment Problem

Du point de vue de la nouvelle économie politique, la compétition entre les voix d'électeurs empêche les hommes et femmes politiques de réaliser des réformes. Puisque ceux-ci visent avant tout leur proper réélection, les conseils scientifiques, demandant souvent des mesures peu populaires, ne sont pas pris en considération par les décideurs politiques. Ce problème soi-disant d'implémentation a souvent été discuté dans la littérature économique et politique. Le présent article ajoute une discussion de la dimension quantitative et structurelle du conseil politique. Pour ce faire nous nous servons des connaissances venant de l'économie des innovations. Nous supposons que les conseils scientifiques ne sont suivis que lorsqu'ils augmentent les chances du politicien d'être réélu. Ce comportement mène cependant en certains domaines de la politique à un sur-ou sous-investissement systématique en conseil, ce qui est ineffectif d'un point de vue de l'ensemble de la société. Après avoir étudié le rôle du conseiller en politique dans le cadre de ce comportement d'investissement, nous discutons une série de mesures qui pourraient servir à contrecarrer ces fausses incitations. Les considérations théoriques sont illustrées à l'aide du cas de l'Allemagne, o� ce genre de problèmes est devenu particulièrement évident au cours de ces dernières années. Copyright WWZ and Helbing & Lichtenhahn Verlag AG 2004.