Jan Nordstrom

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Stable and accurate interface conditions are derived for the linear advection-diffusion equation. The conditions are functionally independent of the spatial order of accuracy and rely only on the form of the discrete operator. We focus on high-order finite-difference operators that satisfy the summation-by-parts (SBP) property. We prove that stability is a(More)
Boundary and interface conditions for high order finite difference methods applied to the constant coefficient Euler and Navier-Stokes equations are derived. The boundary conditions lead to strict and strong stability. The interface conditions are stable and conservative even if the finite difference operators and mesh sizes vary from domain to domain.(More)
Boundary and interface conditions are derived for high order finite difference methods applied to mult, idimensional linear problems in curvilmear coordinates. The boundary and interface conditious lead to conservative schelnes and strict, and strong stability provided that certain metric conditions are met. Key words, high-order finite-difference numerical(More)
This study was designed to determine the folate status of an adolescent population and to demonstrate the effect of folic acid supplementation on subjects with low folate status. In phase one, folate status was evaluated in a biracial sample of 164 adolescents 12 to 15 years old. Socioeconomic, demographic, anthropometric, and 7-day food record data were(More)
We propose new global arti cial boundary conditions (ABCs) for computation of ows with propulsive jets. The algorithm is based on application of the di erence potentials method (DPM). Previously, similar boundary conditions have been implemented for calculation of external compressible viscous ows around nite bodies. The proposed modi cation substantially(More)
The nutritional status of 547 participants of the Title VII Nutrition Program for the Elderly was assessed by anthropometric, biochemical, and dietary means. The nutriture for vitamins A and C was positively associated with frequency of participation in the program using biochemical and dietary methods of assessment. A significant smaller percentage of(More)
Nutrient intake of elderly persons as determined by dietary histories based on food frequencies was examined in relation to various socioeconomic factors. A significantly larger proportion of women than of men had inadequate intakes for energy, calcium, iron, thiamin, and riboflavin. Housing, education, marital status, and work experiences were(More)