Analysis and specification tools in relation to the APSE

Ada and the Ada Programming Support Environment (APSE) specifically address the phases of the system/software life cycle which follow after the user's problem was translated into system and software development specifications. The waterfall model of the life cycle identifies the analysis and requirements definition phases as preceeding program design and coding. Since Ada is a programming language and the APSE is a programming support environment, they are primarily targeted to support program (code) development, tecting, and maintenance. The use of Ada based or Ada related specification languages (SLs) and program design languages (PDLs) can extend the use of Ada back into the software design phases of the life cycle. Recall that the standardization of the APSE as a programming support environment is only now happening after many years of evolutionary experience with diverse sets of programming support tools. Restricting consideration to one, or even a few chosen specification and design tools, could be a real mistake for an organization or a major project such as the Space Station, which will need to deal with an increasingly complex level of system problems. To require that everything be Ada-like, be implemented in Ada, run directly under the APSE, and fit into a rigid waterfall model of the life cycle would turn a promising support environment into a straight jacket for progress

Helium 3/Helium 4 dilution cryocooler for space

Prototype dilution cryocoolers based on dilution refrigeration and adiabatic demagnetization refrigeration (ADR) cycles were designed, constructed, and tested. Although devices the devices did not operate as fully functional dilution cryocoolers, important information was gathered. The porous metal phase separator was demonstrated to operate in the -1-g configuration; this phase separation is the critical element in the He-3 circulation dilution cryocooler. Improvements in instrumentation needed for additional tests and development were identified

Appendix B: Systemic risk and the financial system (background paper)

The Federal Reserve Bank of New York released a report -- New Directions for Understanding Systemic Risk -- that presents key findings from a cross-disciplinary conference that it cosponsored in May 2006 with the National Academy of Sciences' Board on Mathematical Sciences and Their Applications. ; The pace of financial innovation over the past decade has increased the complexity and interconnectedness of the financial system. This development is important to central banks, such as the Federal Reserve, because of their traditional role in addressing systemic risks to the financial system. ; To encourage innovative thinking about systemic issues, the New York Fed partnered with the National Academy of Sciences to bring together more than 100 experts on systemic risk from 22 countries to compare cross-disciplinary perspectives on monitoring, addressing and preventing this type of risk. ; This report, released as part of the Bank's Economic Policy Review series, outlines some of the key points concerning systemic risk made by the various disciplines represented -including economic research, ecology, physics and engineering - as well as presentations on market-oriented models of financial crises, and systemic risk in the payments system and the interbank funds market. The report concludes with observations gathered from the sessions and a discussion of potential applications to policy. ; The three papers presented in this conference session highlighted the positive feedback effects that produce herdlike behavior in markets, and the subsequent discussion focused in part on means of encouraging heterogeneous investment strategies to counter such behavior. Participants in the session also discussed the types of models used to study systemic risk and commented on the challenges and trade-offs researchers face in developing their models.Financial risk management ; Financial markets ; Financial stability ; Financial crises

Genetic algorithms using Galib

GAlib is a C++ library of genetic algorithm objects that was recently developed at the Massachusetts Institute of Technology. This thesis is to demonstrate its functionality and versatility for implementing haploid tripartite genetic algorithms; We first built a test bed in which GAlib could be used. To achieve this, we used GAlib to solve the Traveling Salesman Problem and implemented two-opt and simulated annealing for compariSon We then examined the use of genetic algorithms for finding loop invariants. We used GAlib successfully to build a model but results remain inconclusive; In our main thrust we applied genetic algorithms to train and develop neural networks. To develop neural network architectures we used two different methods of representing neural networks: connection matrices and graph-generation grammars. We were able to demonstrate that genetic algorithms are an effective tool for training networks as well as for finding network architectures

A small, single stage orifice pulse tube cryocooler demonstration

This final report summarizes and presents the analytical and experimental progress in the present effort. The principal objective of this effort was the demonstration of a 0.25 Watt, 80 Kelvin orifice pulse tube refrigerator. The experimental apparatus is described. The design of a partially optimized pulse tube refrigerator is included. The refrigerator demonstrates an ultimate temperature of 77 K, has a projected cooling power of 0.18 Watts at 80 K, and has a measured cooling power of 1 Watt at 97 K, with an electrical efficiency of 250 Watts/Watt, much better than previous pulse tube refrigerators. A model of the pulse tube refrigerator that provides estimates of pressure ratio and mass flow within the pulse tube refrigerator, based on component physical characteristics is included. A model of a pulse tube operation based on generalized analysis which is adequate to support local optimization of existing designs is included. A model of regenerator performance based on an analogy to counterflow heat exchangers is included

A helium-3/helium-4 dilution cryocooler for operation in zero gravity

This research effort covered the development of He-3/He-4 dilution cryocooler cycles for use in zero gravity. The dilution cryocooler is currently the method of choice for producing temperatures below 0.3 Kelvin in the laboratory. However, the current dilution cryocooler depends on gravity for their operation, so some modification is required for zero gravity operation. In this effort, we have demonstrated, by analysis, that the zero gravity dilution cryocooler is feasible. We have developed a cycle that uses He-3 circulation, and an alternate cycle that uses superfluid He-4 circulation. The key elements of both cycles were demonstrated experimentally. The development of a true 'zero-gravity' dilution cryocooler is now possible, and should be undertaken in a follow-on effort

Resource inequality and quality of secondary education: a study of uneven policy in rural schools of southwestern Nigeria

Recent Studies have investigated the influence of the resource factor on the quality of secondary education (QSE) in Nigeria. However, the research on the resource factor as a predictor of quality of secondary education in rural communities of Southwestern Nigeria remains scanty. This study, therefore, investigated the contributions of the resource factor (RF: Resource Adequacy-RA and Resource Utilization-RU) to QSE in rural communities of Southwestern Nigeria (RCSN). The study was located within a pragmatic paradigm that incorporated the convergent parallel design in the collection, analysis and interpretation of the qualitative and quantitative data. The multi-level mixed methods sampling technique was adopted in selecting 467 secondary school graduates, while total enumeration technique was adopted in selecting 134 teachers. Six participants for the Key Informant Interviews comprised three principals and three senior officials from the Teaching Service Commission and Ministry of Education from three selected states in southwestern Nigeria. Two research questions were raised, and one hypothesis was formulated for the study. Two research instruments, namely, the Secondary School Graduate Aptitude Test (SSGAT) and Resource Factor Teachers’ Questionnaire (RFTQ), with reliability coefficients of 0.715 and 0.853, respectively, were used for the study. Quantitative data were analyzed using descriptive statistics and Pearson Product Moment Correlation, while qualitative data were analyzed with content analysis. The resource factor with resource adequacy (x=2.50)  and resource utilization (x=2.77) influenced QSE. The resource factor (r=0.75) had a negative significant relationship with QSE. The study affirmed that addressing resource inequality in rural communities is urgently required to stem the ebbing tide of quality secondary education in Nigeria

Food fortification - a feasible, cost-effective option in the fight against vitamin A deficiency in South Africa

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Gravity Probe-B: the Stanford General Relativity Experiment as a Shuttle Payload

Gravity Probe-B (GP-B) is an experiment under Phase B study at Marshall Space Flight Center which is designed to measure general relativistic induced torques on a gyroscope in orbit about the earth. The measurement of the relativistic effects requires that the gyror scope be nearly perfect in spherical shape and be shielded from the influences of nonre! ati vis tic effects. To accomplish these requirements, the spacecraft design includes provisions for superconducting magnetic shields, superconducting readout electonics, drag free gyro suspension, a drag free spacecraft, and provision for gyroscope spin-up at cryogenic temperatures. The spherical rotor fabrication has resulted in advances in manufacturing and measurement techniques in order to meet the experiment requirements. An essential feature of the spacecraft system which will be launched by the Shuttle is a large volume liquid helium dewar which will supply cooling to maintain the gyros and shields at a few degrees kelvin for over a one year duration. The helium which is boiled off is used to maintain drag free control of the spacecraft. This paper will discuss the design requirements for the experiment, the essential features of the proposed spacecraft, the gyro manufacturing technology, the gas spin-up method, and the liquid helium technology

Entertainment 721

The goal of this project was to design a luxury, aesthetically pleasing entertainment system with a TV lift mechanism that could be remote controlled. The design would also include a cooling cabinet for gaming systems, a remote locking system, and additional storage. Using a morphological chart and weighted decision matrix for each subsystem key features were determined to be included in the design. Several performance benchmarks were determined to accomplish the team’s design. Almost every benchmark was successful in the build of the first prototype. Several heat calculations and FEA analyses were performed on the system to ensure the success of the system. The design was overall determined to be a success, and some ideas for future improvements were proposed by the team