Aligning component upgrades

Modern software systems, like GNU/Linux distributions or Eclipse-based development environment, are often deployed by selecting components out of large component repositories. Maintaining such software systems by performing component upgrades is a complex task, and the users need to have an expressive preferences language at their disposal to specify the kind of upgrades they are interested in. Recent research has shown that it is possible to develop solvers that handle preferences expressed as a combination of a few basic criteria used in the MISC competition, ranging from the number of new components to the freshness of the final configuration. In this work we introduce a set of new criteria that allow the users to specify their preferences for solutions with components aligned to the same upstream sources, provide an efficient encoding and report on the experimental results that prove that optimising these alignment criteria is a tractable problem in practice.Comment: In Proceedings LoCoCo 2011, arXiv:1108.609

Far-infrared polarimetry from the Stratospheric Observatory for Infrared Astronomy

Multi-wavelength imaging polarimetry at far-infrared wavelengths has proven to be an excellent tool for studying the physical properties of dust, molecular clouds, and magnetic fields in the interstellar medium. Although these wavelengths are only observable from airborne or space-based platforms, no first-generation instrument for the Stratospheric Observatory for Infrared Astronomy (SOFIA) is presently designed with polarimetric capabilities. We study several options for upgrading the High-resolution Airborne Wideband Camera (HAWC) to a sensitive FIR polarimeter. HAWC is a 12 x 32 pixel bolometer camera designed to cover the 53 - 215 micron spectral range in 4 colors, all at diffraction-limited resolution (5 - 21 arcsec). Upgrade options include: (1) an external set of optics which modulates the polarization state of the incoming radiation before entering the cryostat window; (2) internal polarizing optics; and (3) a replacement of the current detector array with two state-of-the-art superconducting bolometer arrays, an upgrade of the HAWC camera as well as polarimeter. We discuss a range of science studies which will be possible with these upgrades including magnetic fields in star-forming regions and galaxies and the wavelength-dependence of polarization.Comment: 12 pages, 5 figure

ATLAS Great Lakes Tier-2 Computing and Muon Calibration Center Commissioning

Large-scale computing in ATLAS is based on a grid-linked system of tiered computing centers. The ATLAS Great Lakes Tier-2 came online in September 2006 and now is commissioning with full capacity to provide significant computing power and services to the USATLAS community. Our Tier-2 Center also host the Michigan Muon Calibration Center which is responsible for daily calibrations of the ATLAS Monitored Drift Tubes for ATLAS endcap muon system. During the first LHC beam period in 2008 and following ATLAS global cosmic ray data taking period, the Calibration Center received a large data stream from the muon detector to derive the drift tube timing offsets and time-to-space functions with a turn-around time of 24 hours. We will present the Calibration Center commissioning status and our plan for the first LHC beam collisions in 2009.Comment: To be published in the proceedings of DPF-2009, Detroit, MI, July 2009, eConf C09072

Gaining Ground: Value-Added Analysis for Massachusetts

The premise of standards-based reform in Massachusetts is that a statewide commitment to standards, teaching, assessment, and accountability will lead to greater learning opportunities, higher achievement, a narrowing of the achievement gap, and a more promising future for all of the Commonwealth's students. And indeed, ten years after the passage of the 1993 Massachusetts Education Reform Act, there is strong evidence-from rising scores on state and national tests to testimony from students and teachers themselves - that Massachusetts schools and students are rising to the challenge provided by rigorous academic standards.Yet we have hardly begun to tap the wealth of information that the state has gathered on student learning. Federal "No Child Left Behind" legislation requires states to measure all students' progress toward "Proficiency". While Massachusetts has a sophisticated, even complex, state accountability system, the current system does not allow the Commonwealth to follow individual students' academic trajectory toward proficiency over time. Our current accountability system does not enable us to measure individual students' academic achievement over time.The purpose of this paper is to propose that Massachusetts' accountability plan for schools and districts include a value-added component-a goal that can be realized given key opportunities which now exist. To meet federal NCLB mandates, Massachusetts is required to test all students annually in grades 3 through 8 by 2006-a process in which the Commonwealth has now invested significant time and fiscal resources. With the state's newly developed infrastructure and commitment to annual testing, value-added assessment has become a practical, viable reality in Massachusetts.To explore how better use of student achievement data could enhance our current system of accountability and school improvement, the Rennie Center convened a diverse group - representing teachers' unions, parents, school committees, superintendents, principals, and other education experts - with whom we consulted over several months in preparation of this report. The group focused its attention on the measurement, over time, of student learning gains. We believe that such a system will enhance: The state's capacity to make fair judgments about school effectiveness;Teachers' capacity to provide focused learning support for students;Parents' understanding of their children's academic growth in school; andAdministrators' and local policymakers' decisions about how to improve educational programs.This paper presents the Rennie Center's conclusions about how and why Massachusetts should supplement its current accountability system with value-added analysis. We do not see value-added analysis as a substitute but rather as a complement that adds breadth and depth

On-sky single-mode fiber coupling measurements at the Large Binocular Telescope

The demonstration of efficient single-mode fiber (SMF) coupling is a key requirement for the development of a compact, ultra-precise radial velocity (RV) spectrograph. iLocater is a next generation instrument for the Large Binocular Telescope (LBT) that uses adaptive optics (AO) to inject starlight into a SMF. In preparation for commissioning iLocater, a prototype SMF injection system was installed and tested at the LBT in the Y-band (0.970-1.065 $\mu$m). This system was designed to verify the capability of the LBT AO system as well as characterize on-sky SMF coupling efficiencies. SMF coupling was measured on stars with variable airmasses, apparent magnitudes, and seeing conditions for six half-nights using the Large Binocular Telescope Interferometer. We present the overall optical and mechanical performance of the SMF injection system, including details of the installation and alignment procedure. A particular emphasis is placed on analyzing the instrument's performance as a function of telescope elevation to inform the final design of the fiber injection system for iLocater.Comment: 11 pages, 7 figure

Monitoring-Based Commissioning: Tracking the Evolution and Adoption of a Paradigm-Shifting Approach to Retro-Commissioning

Proceedings of the 2012 ACEEE Summer Study (Panel 4, Paper 1130). Monitoring-based commissioning (MBCx) emphasizes permanent energy performance metering and trending—for diagnosis of energy waste, for savings accounting, and to enable persistence of savings. Emphasis on monitoring represents a paradigm shift for the retro-commissioning (RCx) industry, which has traditionally relied upon test protocols and modeled savings estimates. Since 2004, a major monitoring-based commissioning program at twenty-five California university campuses has evolved to meet the changing needs of university and utility partners. More recently the monitoring-based approach has been adopted by third-party programs in California. We present information on the progression of program design and results for the multiple phases of the original program, along with a look at third-party and other programs adopting similar program features