Syncopate

https://digitalcommons.library.umaine.edu/mmb-vp/2567/thumbnail.jp

Design and Testing of a Resilient COTS Point of Load Converter for Deep Space CubeSats

To support the development of the upcoming Binar Space Program 12U Explorer Class platform, currently being designed for lunar and interplanetary research applications, the design and testing of a modular Gallium Nitride (GaN) based Point of Load (PoL) converter is being undertaken. The converter has been designed to supply power to high-transient-current loads, such as communications systems, by regulating down a higher voltage derived from a range of common CubeSat battery configurations to a target voltage of 5V. The system consists of parallel-connected linear regulator and buck converter stages which deliver power to the load through a high-side current sense circuit. The current sense resistor has a fault tolerant current-to-voltage conversion stage followed by a hysteretic comparison trigger stage, feeding a majority-voter subsystem. The output from the majority voter is used as feedback to automatically enable the normally isolated buck converter when a high load current condition is detected at the output. The majority voter, power switches, linear regulator and Buck converter have been implemented using Gallium Nitride High Electron Mobility Transistors (GaN HEMT). Gallium nitride has been selected to take advantage of the high power density and ionizing radiation tolerance intrinsic to the technology

Progress Towards a 2012 Landsat Launch

The Landsat Data Continuity Mission (LDCM) is on schedule for a December 2012 launch date. The mission is being managed by an interagency partnership between NASA and the U.S. Geological Survey (USGS). NASA leads the development and launch of the satellite observatory while leads ground system development. USGS will assume responsibility for operating the satellite and for collecting, archiving, and distributing the LDCM data following launch. When launched the satellite will carry two sensors into orbit. The Operational Land Imager (OLI) will collect data for nine shortwave spectral bands with a spatial resolution of 30 m (with a 15 m panchromatic band). The Thermal Infrared Sensor (TIRS) will coincidently collect data for two thermal infrared bands with a spatial resolution of 100 m. The OLI is fully assembled and tested and has been shipped by it?s manufacturer, Ball Aerospace and Technology Corporation, to the Orbital Sciences Corporation (Orbital) facility where it is being integrated onto the LDCM spacecraft. Pre-launch testing indicates that OLI will meet all performance specification with margin. TIRS is in development at the NASA Goddard Space Flight Center (GSFC) and is in final testing before shipping to the Orbital facility in January, 2012. The ground data processing system is in development at the USGS Earth Resources Observation and Science (EROS) Center. The presentation will describe the LDCM satellite system, provide the status of system development, and present prelaunch performance data for OLI and TIRS. The USGS has committed to renaming the satellite as Landsat 8 following launch

Incremental Semantic Evaluation for Interactive Systems: Inertia, Pre-emption, and Relations

Although schemes for incremental semantic evaluation have been explored and refined for more than two decades, the demands of user interaction continue to outstrip the capabilities of these schemes. The feedback produced by a semantic evaluator must support the user's programming activities: it must be structured in a way that provides the user with meaningful insight into the program (directly, or via other tools in the environment) and it must be timely. In this paper we extend an incremental attribute evaluation scheme with three techniques to better meet these demands within the context of a modeless editing system with a flexible tool integration paradigm. Efficient evaluation in the presence of syntax errors (which arise often under modeless editing) is supported by giving semantic attributes inertia: a tendency to not change unless necessary. Pre-emptive evaluation helps to reduce the delays associated with a sequence of edits, allowing an evaluator to "keep pace" with the user. Relations provide a general means to capture semantic structure (for the user, other tools, and as attributes within an evaluation) and are treated efficiently using a form of differential propagation. The combination of these three techniques meets the demands of user interaction; leaving out any one does not

Smoke Your Troubles Away

No cover arthttps://scholarsjunction.msstate.edu/cht-sheet-music/10282/thumbnail.jp

Untangling the Mechanisms of Lattice Distortions in Biogenic Crystals across Scales

Biomineralized structures are complex functional hierarchical assemblies composed of biomineral building blocks joined together by an organic phase. The formation of individual mineral units is governed by the cellular tissue component that orchestrates the process of biomineral nucleation, growth, and morphogenesis. These processes are imprinted in the structural, compositional, and crystallographic properties of the emerging biominerals on all scales. Measurement of these properties can provide crucial information on the mechanisms that are employed by the organism to form these complex 3D architectures and to unravel principles of their functionality. Nevertheless, so far, this has only been possible at the macroscopic scale, by averaging the properties of the entire composite assembly, or at the mesoscale, by looking at extremely small parts of the entire picture. In this study, the newly developed synchrotron-based dark-field X-ray microscopy method is employed to study the link between 3D crystallographic properties of relatively large calcitic prisms in the shell of the mollusc Pinna nobilis and their local lattice properties with extremely high angular resolution down to 0.001°. Mechanistic links between variations in local lattice parameters and spacing, crystal orientation, chemical composition, and the deposition process of the entire mineral unit are unraveled

Raising awareness of the occupational health of older construction workers

Background Due to demographic, political and economic pressures, there are now real benefits to be gained from retaining older workers within the construction industry. However the health of such workers, and its consequences for continued working, needs to be more widely appreciated. Aims The aim of the research project being undertaken by the Innovative Manufacturing and Construction Research Centre (IMCRC) at Loughborough University, UK, is to identify the key health issues affecting older construction workers and, from there, develop wearable devices which will simulate these health effects and their consequential impacts on both working and home life. When worn, such devices will enable other industry members (managers, architects, equipment designers, etc) to better appreciate the challenges faced by older workers and, through this improved awareness, contribute to an attitude-shift within the industry. This paper discusses the need to raise awareness of older construction worker health; the rationale for an approach using simulation and the research undertaken to date as well as presenting analogous case studies. Methods A triangulated approach combining: a review of current knowledge in this area, worker interviews and health professional consultations is proposed. From the resultant data a specification will be developed which will detail which health conditions, and what aspects of them, are to be developed into simulation devices. The devices will developed to meet the specification as closely as is possible within technological, ethical, cost and other constraints. The intention is to then pilot the devices with key groups within the industry to confirm proof-of-concept. Results/conclusions Whilst there are no results to date, a case study demonstrating the benefits to be obtained from changing attitudes through increased awareness, which is brought about by enabling third parties to directly experience a heath condition for themselves, will be presented

Founders Day 1959

Founders Day 1959 Reel #12

Incremental Context-Sensitive Evaluation in Context

Although techniques for implementing or generating incremental semantic evaluators have been explored and refined for more than two decades, several pragmatic concerns still impede the use of such techniques in practical development environments. This report not only addresses some of these concerns, but furthermore demonstrates the need to consider the problem of incremental semantic evaluation in context. The practical concerns addressed here stem from both user interaction and architectural requirements. In particular an innovative preemptive evaluation scheme is presented which helps to reduce delays associated with semantic evaluation over a sequence of edits. Furthermore, a technique for assigning attributes to syntactically erroneous material (the introduction of which is inevitable in a syntax recognition editor) is described, as well as a novel approach to handling "long-distance" semantic effects using fine-grained incremental evaluation of relations

Improving Data Infrastructure to Reduce Firearms Violence

In the fall of 2020, Arnold Ventures, a philanthropy dedicated to maximizing opportunity and minimizing injustice, and NORC at University of Chicago, an objective nonpartisan research institution, released the Blueprint for a US Firearms Infrastructure (Roman, 2020). The Blueprint is the consensus report of an expert panel of distinguished academics, trailblazing practitioners, and government leaders. It describes 17 critical reforms required to modernize how data about firearms violence of all types (intentional, accidental, and self-inflicted) are collected, integrated and disseminated. This project, which is also supported by Arnold Ventures, takes the conceptual priorities described in the Blueprint and proposes specific new steps for implementation.The first step in building a better firearms data infrastructure is to acknowledge where we currently stand. In The State of Firearm Data in 2019 (Roman, 2019), the expert panel found that while there are a substantial number of data sources that collect data on firearms violence, existing datasets and data collections are limited, particularly around intentional injuries. There is some surveillance data, but health data on firearms injuries are kept separately from data on crimes, and there are few straightforward ways to link those data. Data that provide context for a shooting--where the event took place, and what the relationship was between victim and shooter--are not available alongside data on the nature of injuries. Valuable data collections have been discontinued, data are restricted by policy, important data are not collected, data are often difficult to access, and contemporary data are often not released in a timely fashion or not available outside of specialized settings. As a result, researchers face vast gaps in knowledge and are unable to leverage existing data to build the evidence base necessary to adequately answer key policy questions and inform firearms policymaking.In the Blueprint, the expert panel developed a set of recommendations organized around a reconceptualization of how data are collected and who collects data. The broad themes from the Blueprint are as follows:Almost all surveillance data in health and criminal justice is generated locally. It is a high priority to provide information, technical assistance, implementation supports, and funding to state and local governments to improve their collections.Comprehensive monitoring of all federal data collections is needed to ensure that important data elements are being collected, data gaps are being addressed, and quality issues are quickly resolved.Timely dissemination of key data is important, including the development of guidelines to ensure consistency across collections and that resources are made available to speed reporting for collections with historical delays.Improvement is needed in strategic communication about the purpose and use of data to federal agencies, researchers and to the general public.The current report builds on the Blueprint by developing implementation guidance for key recommendations. Where the Blueprint included actionable recommendations, such as naming discontinued surveys that should be resurrected, this report develops specific recommendations for implementation. The report is centered on three topics that were the highest priority for the expert panel but that required additional research before guidance could be disseminated. The research findings from that additional investigation are reported here, and recommendations to facilitate implementation are described. The three topic areas are as follows:The creation of a nonfatal firearms injury databaseIncreasing the quality, availability, and usefulness of firearms data for research and policyPractical steps for building state capacity and infrastructure to use data for evidence-based decision-makin