Advanced spacecraft: What will they look like and why

The next century of spaceflight will witness an expansion in the physical scale of spacecraft, from the extreme of the microspacecraft to the very large megaspacecraft. This will respectively spawn advances in highly integrated and miniaturized components, and also advances in lightweight structures, space fabrication, and exotic control systems. Challenges are also presented by the advent of advanced propulsion systems, many of which require controlling and directing hot plasma, dissipating large amounts of waste heat, and handling very high radiation sources. Vehicle configuration studies for a number of theses types of advanced spacecraft were performed, and some of them are presented along with the rationale for their physical layouts

A multidimensional finite element method for CFD

A finite element method is used to solve the equations of motion for 2- and 3-D fluid flow. The time-dependent equations are solved explicitly using quadrilateral (2-D) and hexahedral (3-D) elements, mass lumping, and reduced integration. A Petrov-Galerkin technique is applied to the advection terms. The method requires a minimum of computational storage, executes quickly, and is scalable for execution on computer systems ranging from PCs to supercomputers

Sprayable birefringent coating enables strain measurements on large surfaces

Birefringent coating for strain measurements on large surfaces contains constituents that can be premixed and sprayed as a single component with conventional paint spray equipment. Elevated temperatures are not required for spraying or curing of the coating material which has long pot life

Mixed polyvalent-monovalent metal coating for carbon-graphite fibers

An improved coating of gasification catalyst for carbon-graphite fibers is provided comprising a mixture of a polyvalent metal such as calcium and a monovalent metal such as lithium. The addition of lithium provides a lighter coating and a more flexible coating when applied to a coating of a carboxyl containing resin such as polyacrylic acid since it reduces the crosslink density. Furthermore, the presence of lithium provides a glass-like substance during combustion which holds the fiber together resulting in slow, even combustion with much reduced evolution of conductive fragments. The coated fibers are utilized as fiber reinforcement for composites

Indiana Students Deserve High-Rated School Libraries

According to William Bainbridge, president of School Match, a firm that helps individuals and corporations evaluate 15,892 public school systems and 14,855 private schools; the level of expenditures for library and media services has the highest correlation with student achievement (New Jersey School Board Association Newsletter, 1995). Keith Curry Lance (2004) of the Colorado State Library found that schools with higher rated libraries have 10 to 18 percent better test scores than schools with lower rated libraries

Inefficiency and productivity growth in banking: a comparison of stochastic econometric and thick frontier methods

A comparison of alternative methods for estimating inefficiency and productivity growth in banking, showing that inefficiencies are sufficiently large to dominate scale economies and that measured technological progress has been small, or even negative, as a result of institutional events that occurred during 1977-88.Banks and banking - Costs ; Production (Economic theory)

A history of Loughborough between c.1810 and c.1870: a study of urban changes in a period of demographic growth and stagnation

This thesis is a study of urban change during an unusual period in the demographic history of Loughborough. Part, A is concerned with the theme in relation to the local economy. Chapter 1 deals with the introduction of a machine-made lace industry to the town, the rapid growth in population which followed and its subsequent decline. Demographic stagnation then developed and this is associated in chapter 2 with a cottagebased hosiery industry which had remained as the principal industry when the centre of the lace trade moved to Nottingham. Chapter 3 provides an intensive study of the occupational structure of the town at this period; it is based on, an analysis by computer of the 1851 census. At this time the economy was flat but the first signs of change in the industrial structure were beginning to appear. In Chapter 4 the theme is pursued as innovation rejuvenated the hosiery trade and demographic growth was resumed. Chapter 5 surveys the whole period for which reasonably detailed censuses exist, that is, from 1841, to 1881, and the themes of the earlier chapters are put into a wider perspective of the occupational flow of the town. In Chapter 6a specific factor is given attention; this was the status of Loughborough as a market town, which offered employment and income throughout the period, during industrial recession as well as expansion. Part B is concerned with the social aspects of the events narrated above. Chapter 7 offers an analysis of social patterns in the town in 1851 based, like Chapter 3, on the census of that year. The next chapter deals with some social responses to growth and stagnationt the chief of which were Luddism and Chartism, although the local education service and enviromental amelioration are also discussed. Chapter 9 concludes this section with an examination of the urban geography of Loughborough in relation to social class; an original system for the identification of social class from census and other material is propounded. The Appendices provide additional information which could not be conveniently placed within the main body of the thesis. Appendix 1 offers more historical background and Appendix 2 discusses in detail the methods used in the 1851 census analysis upon which chapters 31, 7 and 9 are based. Appendices 3,4,5 and 6 provide additional data for Chapters 3 and 9. Since much of the thesis is devoted to a discussion on the influence, of textile manufacture in Loughborough, the final Appendix consists of notes on the basic characteristics of the three principal machines

OMC Compressor Case

This report summarizes efforts expended in the development of an all-composite compressor case. Two pre-production units have been built, one utilizing V-CAP and one utilizing AFR-700B resin systems. Both units have been rig tested at elevated temperatures well above design limit loads. This report discusses the manufacturing processes, test results, and Finite Element Analysis performed. The V-CAP unit was funded by NASA-Lewis Research Center in 1994 under contract number NAS3- 27442 for Development of an All-Composite OMC Compressor Case. This contract was followed by an Air Force study in 1996 to build and identical unit using the AFR-700B resin system in place of the V-CAP system. The second compressor case was funded under U.S. Air Force contract F33615-93-D-5326, Advanced Materials for Aerospace Structures Special Studies (AMAS3), Delivery Order 0021 entitled "Advanced Polymeric Composite Materials and Structures Technology for Advanced High Temperature Gas Turbine Engines.' Initial studies using the V-CAP resin system were undertaken in 1993 under a NASA Lewis contract (NAS3-26829). A first prototype unit was developed in a joint program between Textron-Lycoming (now Allied Signal) and Brunswick (now Lincoln Composites). This unit included composite end closures using low density, high temperature molded end closures. The units was similar in size and shape to a titanium case currently used on the PT-21 0 engine and was funded as part of the integrated High Performance Turbine Engine Technology (EHPTET) initiative of DOD and NASA

Gas Sorption and Luminescence Properties of a Terbium(III)-Phosphine Oxide Coordination Material with Two-Dimensional Pore Topology

The structure, stability, gas sorption properties and luminescence behaviour of a new lanthanide-phosphine oxide coordination material are reported. The polymer PCM-15 is based on Tb(III) and tris(p-carboxylated) triphenylphosphine oxide and has a 5,5-connected net topology. It exhibits an infinite three-dimensional structure that incorporates an open, two-dimensional pore structure. The material is thermally robust and remains crystalline under high vacuum at 150 degrees C. When desolvated, the solid has a CO2 BET surface area of 1187 m(2) g(-1) and shows the highest reported uptake of both O-2 and H-2 at 77 K and 1 bar for a lanthanide-based coordination polymer. Isolated Tb(III) centres in the as-synthesized polymer exhibit moderate photoluminescence. However, upon removal of coordinated OH2 ligands, the luminescence intensity was found to approximately double; this process was reversible. Thus, the Tb(III) centre was used as a probe to detect directly the desolvation and resolvation of the polymer.Welch Foundation F-1738, F-1631National Science Foundation 0741973, CHE-0847763Chemistr