Lightweight piston

A lightweight piston composed of carbon-carbon composites is presented. The use of carbon-carbon composites over conventional materials, such as aluminum, reduces piston weight and improves thermal efficiency of the internal combustion reciprocation engine. Due to the negligible coefficient of thermal expansion and unique strength at elevated temperatures of carbon-carbon, the piston-to-cylinder wall clearance is so small as to eliminate the necessity for piston rings. Use of the carbon-carbon composite has the effect of reducing the weight of other reciprocating engine components allowing the piston to run at higher speeds and improving specific engine performance

Composite piston

A composite piston structure is disclosed which provides a simple and reliable means for joining a carbon-carbon or ceramic piston cap with a metallic piston body. Attachment is achieved by means of a special geometry which compensates for differences in thermal expansion without complicated mechanical fastening devices. The shape employs a flange created by opposed frustoconical shapes with coincident vertices intersecting on the radial centerline of the piston in order to retain the piston cap. The use of carbon-carbon for the piston cap material allows a close fit between the piston and a cylinder wall, eliminating the need for piston rings. The elimination of extra mechanical parts of previous composite pistons provides a lightweight composite piston capable of extended high temperature operation

Now we are 21: an overview of the longitudinal Life Chances Study

The Brotherhood of St Laurence’s longitudinal Life Chances Study started in Melbourne in 1990. The study has comprised ten stages, the most recent completed in 2012 when the children, who were born in 1990, were 21 years old.This paper presents an overview of the study by outlining the published findings of each stage. It is designed to enable readers to follow up the diverse topics covered over 21 years, to point to the findings and the policy implications that have emerged and to act as a guide for possible future analysis.The study was designed as a population study in an inner urban area. It sought to explore the life chances of a group of children who were born at the same time in the same place but into very diverse families. While the study sample is not representative of all Australian children, aspects of the experiences of these families are likely to be shared by many others. The study has continued to follow the families as they moved away from the inner suburbs.Readers can also turn to the original reports for their rich detail including the parents’ and young people’s own descriptions of their experiences as well as quantitative analysis. The reports of the early stages are available through the Brotherhood of St Laurence and some libraries. The reports of stages 6 onwards are available on the Brotherhood’s website (www.bsl.org.au)

Lightweight piston architecture

The invention is an improvement in a lightweight carbon-carbon composite piston, the improvement uses near-net shape knitted or warp-interlock preforms to improve the structural qualities of the piston. In its preferred embodiment, a one piece, tubular, closed-ended, knitted preform (a sock) of carbon fibers embedded within the matrix of the piston structure forms the crown, side wall, skirt and inner surface of the piston, and wrap-interlock preforms strengthen the piston crown and wrist pin bosses

On kk-point configuration sets with nonempty interior

We give conditions for $k$-point configuration sets of thin sets to have nonempty interior, applicable to a wide variety of configurations. This is a continuation of our earlier work \cite{GIT19} on 2-point configurations, extending a theorem of Mattila and Sj\"olin \cite{MS99} for distance sets in Euclidean spaces. We show that for a general class of $k$-point configurations, the configuration set of a $k$-tuple of sets, $E_1,\,\dots,\, E_k$, has nonempty interior provided that the sum of their Hausdorff dimensions satisfies a lower bound, dictated by optimizing $L^2$-Sobolev estimates of associated generalized Radon transforms over all nontrivial partitions of the $k$ points into two subsets. We illustrate the general theorems with numerous specific examples. Applications to 3-point configurations include areas of triangles in $\mathbb R^2$ or the radii of their circumscribing circles; volumes of pinned parallelepipeds in $\mathbb R^3$; and ratios of pinned distances in $\mathbb R^2$ and $\mathbb R^3$. Results for 4-point configurations include cross-ratios on $\mathbb R$, triangle area pairs determined by quadrilaterals in $\mathbb R^2$, and dot products of differences in $\mathbb R^d$.Comment: 32 pages, no figure

Turning 21: Life chances and uncertain transitions

  Traditionally, the transition from school to work has been important for young adults, and turning 21 was recognised as the marker of adulthood in Australia, when young people had jobs—and even families of their own. Social and economic changes over the past 30 years or so have made the transition from school to work more complex and less clear-cut. This report documents the factors that shape the lives of 123 young participants in the Life Chances Study, as they turn 21. Key points •    Stereotypes about young people obscure the diverse and complex lives of 21-year-olds. This diversity is shaped by family income, gender, ethnic background and resources. The 21-year-olds included university and TAFE students, full-time and part-time workers, young parents and jobseekers. Many were both studying and working. •    Those with fewer resources were more likely to identify as adults. They faced challenges that those with more resources could avoid. While some welcomed adulthood, others felt the burden of responsibilities. •    21-year-olds continued to rely on their families for advice, and emotional and financial support. The unequal access to resources reinforced inequalities because even though most had jobs, many still relied on their parents’ financial support—if they could. •    Disadvantage need not be intergenerational. Disadvantage or advantage persisted for some families, but not for all. Childhood in a low-income family did not necessarily condemn children to continuing disadvantage. •    Definitions of a ‘successful’ transition must take into account young people’s multiple activities and their wellbeing. Most 21-year-olds aspired to full-time employment. In this study, most of those who did not have a job and were not studying or in training had caring duties or mental health issues. Labelling these young people as ‘disengaged’ does not sufficiently capture their level of activity or wellbeing. •    Transitions for 21-year-olds are uncertain, but the social and economic resources needed to address this uncertainty are not evenly distributed. Those from high-income backgrounds with strong social supports had greater ‘choice’ while negotiating their pathways than those from lower income backgrounds. •    Policies need to address multidimensional disadvantage. The findings have implications for addressing socioeconomic inequalities as well as for targeted career and vocational guidance. Background The Life Chances Study is a unique longitudinal study initiated by the Brotherhood of St Laurence in 1990 to explore the impacts of family income and associated factors on children over time. It commenced as a study of 167 infants born in inner Melbourne and has followed the families as they have moved elsewhere. In stage 10 of the study we surveyed 123 young people and their parents to see how they were dealing with the important transitions towards adulthood. We also undertook 25 interviews to explore their situations in more depth

Daze fasteners

A daze fastener system for connecting two or more structural elements wherein the structural elements and fastener parts have substantially different coefficient of thermal expansion physical property characteristics is employed in this invention. By providing frusto-conical abutting surfaces between the structural elements and fastener parts any differences in thermal expansion/contraction between the parts is translated to sliding motion and avoids deleterious thermal stresses in the connection. An essential feature for isotropic homogeneous material connections is that at least two sets of mating surfaces are required wherein each set of mating surfaces has line element extensions that pass through a common point

IVOA Recommendation: SAMP - Simple Application Messaging Protocol Version 1.3

SAMP is a messaging protocol that enables astronomy software tools to interoperate and communicate. IVOA members have recognised that building a monolithic tool that attempts to fulfil all the requirements of all users is impractical, and it is a better use of our limited resources to enable individual tools to work together better. One element of this is defining common file formats for the exchange of data between different applications. Another important component is a messaging system that enables the applications to share data and take advantage of each other's functionality. SAMP builds on the success of a prior messaging protocol, PLASTIC, which has been in use since 2006 in over a dozen astronomy applications and has proven popular with users and developers. It is also intended to form a framework for more general messaging requirements

Clique decompositions of multipartite graphs and completion of Latin squares

Our main result essentially reduces the problem of finding an edge-decomposition of a balanced r-partite graph of large minimum degree into r-cliques to the problem of finding a fractional r-clique decomposition or an approximate one. Together with very recent results of Bowditch and Dukes as well as Montgomery on fractional decompositions into triangles and cliques respectively, this gives the best known bounds on the minimum degree which ensures an edge-decomposition of an r-partite graph into r-cliques (subject to trivially necessary divisibility conditions). The case of triangles translates into the setting of partially completed Latin squares and more generally the case of r-cliques translates into the setting of partially completed mutually orthogonal Latin squares.Comment: 40 pages. To appear in Journal of Combinatorial Theory, Series

Saponin Content of Lahontan and Du Puits Alfalfas

Primitive peoples have used saponins for many years to kill fish and as a detergent. In more recent times saponin has been shown to inhibit the growth of chicks, reduce the egg production of laying hens, and to be a possible factor in bloat of ruminant animals