Optimising the design of a piston-ring pack using DoE methods

This paper shows how design of experiments can be used with a ring-pack simulation program to optimise the design of a piston-ring assembly. Ten factors are varied—six describing the ring profile, three ring tensions, and the lubricant viscosity. Statistical analysis shows that there are some significant interactions between some of the factors—an issue that should be considered when performing test- bed measurements on engines. It is shown that an improved design can be achieved that reduces ring losses by 57% whilst reducing upward oil flow by 39%. This could lead to a 7% improvement in fuel economy provided there are no deleterious effects in other parts of the engine

The neural bases of distracter-resistant working memory

A major difference between humans and other animals is our capacity to maintain information in working memory (WM) while performing secondary tasks, which enables sustained, complex cognition. A common assumption is that the lateral prefrontal cortex (PFC) is critical for WM performance in the presence of distracters, but direct evidence is scarce. We assessed the relationship between fMRI activity and WM performance within-subjects, with performance matched across Distracter and No-distracter conditions. Activity in ventrolateral PFC during WM encoding and maintenance positively predicted performance in both conditions, whereas activity in the pre-supplementary motor area (pre-SMA) predicted performance only under distraction. Other parts of dorsolateral and ventrolateral PFC predicted performance only in the No-distracter condition. These findings challenge a lateral PFC-centered view of distracter-resistance, and suggest that the lateral PFC supports a type of WM representation that is efficient for dealing with task-irrelevant input but is nonetheless easily disrupted by dual-task demands

Disproportionate Impact Of K-12 School Suspension And Expulsion On Black Students In Southern States

This report aims to make transparent the rates at which school discipline practices and policies impact Black students in every K-12 public school district in 13 Southern states: Alabama, Arkansas, Florida, Georgia, Kentucky, Louisiana, Mississippi, North Carolina, South Carolina, Tennessee, Texas, Virginia, and West Virginia

Financial Conditions on U.S. Cotton Farms

For the last three years, U.S. cotton producers have been heavily dependent on ad hoc emergency disaster and market loss assistance to cash flow their operations. They have not been alone. Wheat, feed grains, oilseeds and rice producers have also been faced with low commodity prices, adverse weather and the need for substantial government assistance. Price support and direct payments by CCC for fiscal years 1998-2000 averaged $17.5 billion per year (USDA Ag Outlook). Has U.S. program crop agriculture turned the corner or will additional government payments likely be needed to sustain a vulnerable sector? This paper will focus on the outlook for the Agricultural and Food Policy Center’s (AFPC’s) representative cotton farms over the period 2001-2005. The results reported herein are drawn from AFPC Working Paper 00-4 which goes into greater depth on all 82 representative farms and ranches modeled by AFPC.Agribusiness, Agricultural and Food Policy, Crop Production/Industries,

Blurring Boundaries: Transforming Place, Policies, and Partnerships for Postsecondary Education Attainment in Metropolitan Areas

By 2020, more than six out of 10 U.S. jobs will require postsecondary training. Despite a slight increase in college attainment nationally in recent years, the fastest-growing minority groups are being left behind. Only 25 and 18 percent of Blacks and Hispanics, respectively, hold at least an associate's degree, compared with 39 percent of Whites. Without substantial increases in educational attainment, particularly for our nation's already underserved groups, the United States will have a difficult time developing a robust economy.Home to 65 percent of Americans, and a majority of all African Americans and Hispanics (74 and 79 percent, respectively), the 100 largest metropolitan statistical areas (MSAs) can play a strong role in developing this nation's workforce. In fact, to reach a national attainment target that meets our workforce needs, more than half of college degrees could be generated from the these cities. The majority of degrees needed among African-American and Hispanic adults could also be produced in MSAs.Clearly, investing in and organizing around the potential of metropolitan areas is critical, and the stakes have never been higher. Yet the current funding climate requires strategic public and private partnerships to invest in education innovation and human capital development in order to have the most robust impact on sustainable national growth. For this study, the Institute for Higher Education (IHEP) sought to follow up on its previous work examining MSA educational attainment rates by further exploring policies that either inhibit or facilitate degree production, and identifying metropolitan-level, cross-section collaborations that help local leaders contribute to national completion goals