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Galois : a system for parallel execution of irregular algorithms
textA programming model which allows users to program with high productivity and which produces high performance executions has been a goal for decades. This dissertation makes progress towards this elusive goal by describing the design and implementation of the Galois system, a parallel programming model for shared-memory, multicore machines. Central to the design is the idea that scheduling of a program can be decoupled from the core computational operator and data structures. However, efficient programs often require application-specific scheduling to achieve best performance. To bridge this gap, an extensible and abstract scheduling policy language is proposed, which allows programmers to focus on selecting high-level scheduling policies while delegating the tedious task of implementing the policy to a scheduler synthesizer and runtime system. Implementations of deterministic and prioritized scheduling also are described. An evaluation of a well-studied benchmark suite reveals that factoring programs into operators, schedulers and data structures can produce significant performance improvements over unfactored approaches. Comparison of the Galois system with existing programming models for graph analytics shows significant performance improvements, often orders of magnitude more, due to (1) better support for the restrictive programming models of existing systems and (2) better support for more sophisticated algorithms and scheduling, which cannot be expressed in other systems.Computer Science
Rapid screening for Neurospora crassa strains lacking CuZn superoxide dismutase (sod-1)
We have developed a simple system for determining if strains of N. crassa produce functional CuZn superoxide dismutase. We previously isolated N. crassa mutants with null alleles of the sod-1 gene, which encodes this enzyme (Chary et al. submitted)
Food Industry Mergers and Acquisitions Lead to Higher Labor Productivity
Processing plants in eight major food industries were highly productive before being acquired and they significantly improved their labor productivity afterward, Economic Research Service and U.S. Census Bureau researchers found in their analysis of Census data. The plant-level data on production inputs and costs provided a detailed picture of food-production facilities involved in mergers and acquisitions. The industries are meatpacking, meat processing, poultry slaughtering and processing, cheese making, fluid milk processing, flour milling, feed processing, and oilseed crushing. The analysis suggests that mergers and acquisitions contributed to the general improvement in labor productivity, echoing an earlier ERS study. Labor productivity is defined as output per worker.Mergers, acquisitions, labor productivity, consolidation, structural change, Agribusiness, Industrial Organization, Productivity Analysis,
Structural Change in the Meat, Poultry, Dairy and Grain Processing Industries
Consolidation and structural changes in the food industry have had profound impacts on firms, employees, and communities in many parts of the United States. Over 1972-92, eight important food industries underwent a structural transformation in which the number of plants declined by about one-third and the number of employees needed to staff the remaining plants dropped by more than 100,000 (20 percent). The number of plants in one other industry also dropped, but that industry added jobs. Economists generally attribute structural changes such as these to rising or falling demand and shifts in technology. This report examines consolidation and structural change in meatpacking, meat processing, poultry slaughter and processing, cheese products, fluid milk, flour milling, corn milling, feed, and soybean processing. Plant size and output per employee rose sharply in all industries, and even industries with rapidly growing demand—such as soybean processing and poultry slaughter/processing—used fewer plants. These findings suggest that technological change was the major force driving structural change.structural change, food processing, consolidation, grain processing, meat slaughter, dairy processing, Industrial Organization,
Effect of Food Industry Mergers and Acquisitions on Employment and Wages
Empirical analysis of mergers and acquisitions in eight important food industries suggests that workers in acquired plants realized modest increases in employment and wages relative to other workers. Results also show that mergers and acquisitions reduced the likelihood of plant closures while high relative labor costs encouraged plant shutdowns. These results differ from commonly held views that mergers and acquisitions lead to fewer jobs, wage cuts, and plant shutdowns.Food product industries, mergers and acquisitions, plant closures, Agribusiness, Industrial Organization,
Risk Management Strategies by Australian Farmers
Australian farmers operate in one of the most risky environment in the world. They have to cope with various sources of risk in their businesses. This paper reports results of two case studies undertaken to examine the issues of farming risks and risk management strategies in Australia. The first case study found that climate variability, financial risk, marketing risk, and personal risk were regarded as the major sources of farming risk in the Upper Eyre Peninsula of South Australia. The main management strategies used by farmers included diversifying varieties, minimising tillage, minimising area of risky crops and maximising area of the least-risky crop, having high equity, having farm management deposits and other off-farm investments, and "leaving marketing to experts". The second case study revealed that climate variability was ranked as the most important source of farming risk in southwest Queensland. This was then followed by financial risks, government policy, and marketing risks. The main management strategies used were enterprise diversification (having predominantly cattle and farming cash crops), conserving moisture, using zero till planting, diversified sales (selling only part of the farm's production at any one time), and having off-farm investments. The paper then attempts to reconcile the two case studies by comparing the results with studies from the United States of America, Canada, Netherlands, and New Zealand.risk, risk management, strategies, farmers, Australia, Farm Management, Risk and Uncertainty,
Second-order analytic solutions for re-entry trajectories
Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/76344/1/AIAA-1993-3679-680.pd
(1R*,2R*,4S*,5R*,6R*,8S*)-4,8-Dimethyl-2,6-diphenylbicyclo[3.3.1]nonane-2,6-diol
The racemic title compound, C23H28O2, crystallizes in the space group C2/c as a layered structure in which a centrosymmetric three hydrogen bond sequence links four molecules. Both hydroxy groups are involved in this arrangement, but they differ in that one participates in two hydrogen bonds while the other takes part in only one. Between layers, the aromatic rings take part in edge-face interactions [shortest C—H⋯C distances 3.04, 3.10 and 3.12 Å and angle between normal to planes 86.7(2)°], forming a centrosymmetric dimer. The lattice is further stabilized by C—H⋯π interactions involving both methyl (shortest C⋯C 3.82 and 3.97 Å) and methylene (shortest C⋯C 3.60 Å) groups
Redesigning pictographs for patients with low health literacy and establishing preliminary steps for delivery via smart phones.
BackgroundPictographs (or pictograms) have been widely utilized to convey medication related messages and to address nonadherence among patients with low health literacy. Yet, patients do not always interpret the intended messages on commonly used pictographs correctly and there are questions how they may be delivered on mobile devices.ObjectiveOur objectives are to refine a set of pictographs to use as medication reminders and to establish preliminary steps for delivery via smart phones.MethodsCard sorting was used to identify existing pictographs that focus group members found "not easy" to understand. Participants then explored improvements to these pictographs while iterations were sketched in real-time by a graphic artist. Feedback was also solicited on how selected pictographs might be delivered via smart phones in a sequential reminder message. The study was conducted at a community learning center that provides literacy services to underserved populations in Seattle, WA. Participants aged 18 years and older who met the criteria for low health literacy using S-TOFHLA were recruited.ResultsAmong the 45 participants screened for health literacy, 29 were eligible and consented to participate. Across four focus group sessions, participants examined 91 commonly used pictographs, 20 of these were ultimately refined to improve comprehensibility using participatory design approaches. All participants in the fifth focus group owned and used cell phones and provided feedback on preferred sequencing of pictographs to represent medication messages.ConclusionLow literacy adults found a substantial number of common medication label pictographs difficult to understand. Participative design processes helped generate new pictographs, as well as feedback on the sequencing of messages on cell phones, that may be evaluated in future research
Early Operations Flight Correlation of the Lunar Laser Communications Demonstration (LLCD) on the Lunar Atmosphere and Dust Environment Explorer (LADEE)
The Lunar Atmosphere and Dust Environment Explorer (LADEE) mission launched on September 7, 2013 with a one month cruise before lunar insertion. The LADEE spacecraft is a power limited, octagonal, composite bus structure with solar panels on all eight sides with four vertical segments per side and 2 panels dedicated to instruments. One of these panels has the Lunar Laser Communications Demonstration (LLCD), which represents a furthering of the laser communications technology demonstration proved out by the Lunar Reconnaissance Orbiter (LRO). LLCD increases the bandwidth of communication to and from the moon with less mass and power than LROs technology demonstrator. The LLCD Modem and Controller boxes are mounted to an internal cruciform composite panel and have no dedicated radiator. The thermal design relies on power cycling of the boxes and radiation of waste heat to the inside of the panels, which then reject the heat when facing cold space. The LADEE mission includes a slow roll and numerous attitudes to accommodate the challenging thermal requirements for all the instruments on board. During the cruise phase, the internal Modem and Controller avionics for LLCD were warmer than predicted by more than modeling uncertainty would suggest. This caused concern that if the boxes were considerably warmer than expected while off, they would also be warmer when operating and could limit the operational time when in lunar orbit. The thermal group at Goddard Space Flight Center evaluated the models and design for these critical avionics for LLCD. Upon receipt of the spacecraft models and audit was performed and data was collected from the flight telemetry to perform a sanity check of the models and to correlate to flight where possible. This paper describes the efforts to correlate the model to flight data and to predict the thermal performance when in lunar orbit and presents some lessons learned
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