Lanczos eigensolution method for high-performance computers

The theory, computational analysis, and applications are presented of a Lanczos algorithm on high performance computers. The computationally intensive steps of the algorithm are identified as: the matrix factorization, the forward/backward equation solution, and the matrix vector multiples. These computational steps are optimized to exploit the vector and parallel capabilities of high performance computers. The savings in computational time from applying optimization techniques such as: variable band and sparse data storage and access, loop unrolling, use of local memory, and compiler directives are presented. Two large scale structural analysis applications are described: the buckling of a composite blade stiffened panel with a cutout, and the vibration analysis of a high speed civil transport. The sequential computational time for the panel problem executed on a CONVEX computer of 181.6 seconds was decreased to 14.1 seconds with the optimized vector algorithm. The best computational time of 23 seconds for the transport problem with 17,000 degs of freedom was on the the Cray-YMP using an average of 3.63 processors

New information on lending to small businesses and small farms: the 1996 CRA data

As a consequence of recent revisions to the regulations that implement the Community Reinvestment Act (CRA), new information is now publicly available on the geographic distribution of small loans to businesses and farms and on community development lending. Because small businesses and small farms are more likely than larger ones to borrow small amounts, the CRA data on small loans are likely to provide a reasonable measure of the extension of credit to such businesses. Thus, the CRA data provide new opportunities to gauge the flow of credit to communities with differing economic and demographic characteristics. This article presents an initial assessment of the new CRA data on originations and purchases of small business and small farm loans during 1996. The focus of the analysis is on the broad patterns that emerge when the data are reviewed from a national perspective rather than on the lending activities of any individual institution.Small business ; Bank loans ; Agricultural credit

A Lanczos eigenvalue method on a parallel computer

Eigenvalue analyses of complex structures is a computationally intensive task which can benefit significantly from new and impending parallel computers. This study reports on a parallel computer implementation of the Lanczos method for free vibration analysis. The approach used here subdivides the major Lanczos calculation tasks into subtasks and introduces parallelism down to the subtask levels such as matrix decomposition and forward/backward substitution. The method was implemented on a commercial parallel computer and results were obtained for a long flexible space structure. While parallel computing efficiency for the Lanczos method was good for a moderate number of processors for the test problem, the greatest reduction in time was realized for the decomposition of the stiffness matrix, a calculation which took 70 percent of the time in the sequential program and which took 25 percent of the time on eight processors. For a sample calculation of the twenty lowest frequencies of a 486 degree of freedom problem, the total sequential computing time was reduced by almost a factor of ten using 16 processors

INTENTIONAL PURCHASING: Accessible Procurement in Higher Education

Intentional Purchasing is examining products with the intention of purchasing those that are accessible, work well with accessible technology or can be updated to become accessible

Exploring the Effects of Curricula on Fifth-Grade Students\u27 Problem Solving

How does textbook use (i.e. reform-oriented and traditional textbooks) influence fifth-grade students\u27 problem solving

Pilot Survey of Driving Behaviors Associated with Adverse Weather amongst Collegiate Students

Motor vehicle crashes have demonstrated to be one of the leading causes of death and unintentional injury within the United States (Center for Disease Control and Prevention (CDC), 2020). Of the 5,891,000 motor vehicle crashes that occur each year, approximately 21% of these crashes are weather-related (Federal Highway Administration (FHWA), 2020). The population most impacted by motor vehicle crashes within the United States is teens, who are three times more likely to experience crashes than adults (CDC, 2020). To better understand driving behaviors used by early adults, the current study examined defensive driving behaviors implemented by collegiate students to prevent motor vehicle collisions. The purpose of the study was to investigate the driving behaviors of college students during adverse weather conditions. Undergraduate students were recruited, and participants anonymously recorded their responses to questions assessing their driving behavior. The results suggested that students avoid driving in the car in adverse weather (e.g., fog, rain, or ice), but they do not avoid driving during night conditions. Implications of the results are that adverse weather conditions are likely to be avoided by GSUSPH students and all motor vehicle drivers, thus encouraging the public health community to continue designing and implementing developed road strategies to promote driver safety

Proving Operations with Numbers by Using Manipulatives

We will explore number theory topics found in the Common Core State Standards and discuss ways to support student engagement in proof and reasoning. Participants will create proofs for operations with numbers by using manipulatives such as Unifix cubes and base-ten blocks. I will share implications for mathematics teacher educators and teachers

Encouraging Sixth-Grade Students\u27 Problem-Solving Performance by Teaching Through Problem Solving

Abstract: This teaching experiment provided students with continuous engagement in a problem-solving based instructional approach during one mathematics unit. Three sections of sixth-grade mathematics were sampled from a school in Florida, U.S.A. and one section was randomly assigned to experience teaching through problem solving. Students’ problem-solving performance and performance on a unit test were analyzed. The intervention had a positive effect on students’ problem-solving performance whereas the comparison group experienced no changes. ANCOVA analyses suggest that intervention students solved more problems on the posttest than their peers, but the comparison group outperformed the intervention group on the unit test

Middle Grades Preservice Teachers\u27 Experiences with Proof and Reasoning Focused Instruction

The purpose of this session is to explore middle grades mathematics teachers’ perceptions of and experiences using manipulatives to prove mathematics topics. Participants will reason with manipulatives and collaboratively reflect on ways to promote reasoning and proof during preservice coursework

Family, Work, Economy, or Social Policy: Examining Poverty among Children of Single Mothers in Affluent Democracies between 1985-2016

Children of single mothers face higher rates of poverty than children in two-parent households in practically every affluent democracy. While this difference is widely acknowledged, there is little consensus regarding the causes of their poverty and, as a result, little consensus on the best way to address poverty among these children. Explanations include both individual-level, structural, and political explanations in four areas: family structure, labor force activity, economic performance, and welfare generosity. Previous research, however, tends to focus on only one of these four aspects at a time. Using data from the Luxembourg Income Study and the Organisation for Economic Co-operation and Development, spanning a period of 31 years and 25 countries, I test each of these four explanations, examining the effects on children in single mother households separately (n=105,814) and children in both single mother households and children in two-parent households (n=668,549), conducting random intercept between-within logistic regression analysis. Individual-level measures of family structure and labor market activity affect child poverty generally in the expected way. Taking advantage of the longitudinal data at the country level, I focus on within-country change of the structural and political variables. Within-country economic performance is not significantly related to poverty, but welfare generosity, namely family allowances, significantly reduce the odds of poverty. Further, while the effects of family allowance spending are similar for children in both single mother and two parent households, they are stronger for the former than the latter. Yet, the disadvantage of living in a single mother household persists