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We introduce infinite time computable model theory, the computable model theory arising with infinite time Turing machines, which provide infinitary notions of computability for structures built on the reals R. Much of the finite time theory generalizes to the infinite time context, but several fundamental questions, including the infinite time computable analogue of the Completeness Theorem, turn out to be independent of ZFC., Comment: 32 pages

We describe a graph-theoretic syntax for self-referential formulas as well as a four-valued logic to include contradictory and independent formulas. We then explore the degree to which generalized truth tables can be realized in our theory, and go on to describe a model theory for sentential calculus, wherein models are allowed to include contradictions (such as the ``Liar'') and formulas that result from them as an integral part of their structure. This sets the groundwork for a sequel in which we construct models of set theory that include contradictions.

The development of the melt electrospinning model was based on our current solution electrospinning model. Our approach began with the idea that electrospinning is a variation of conventional dry spinning. The notable difference is in the way spinline tensile forces are generated. Once the solution electrospinning model was created, we determined what modifications would be required to create a melt electrospinning model. The major difference with solution electrospinning is the lack of the solvent component in the fiber and thus mass transport would not occur. In order to develop the melt electrospinning model, the fundamental role of electrostatics on fiber diameter reduction was investigated. Parametric studies have indicated the possible role surface charge density plays on the rate of this reduction. [ABSTRACT FROM AUTHOR]

The electrical characterization of the air/hydrogen polymer electrolyte membrane fuel cell is done. The effect of hydrogen flow rate on voltage, resistance and current is investigated at standard conditions. There is an optimum flow rate that gives the maximum voltage and current. The effect of load on thickness and resistivity of various gas diffusion layers (GDL) is measured. Loading reduces the thickness and resistivity of the GDLs. New GDL structures are being made with wet-lay process. A low cost composite polymer electrolyte membrane was developed. It can increase the fuel cell durability when operated at below 80°C. The polymer electrolyte membrane was prepared from Nafion®/polypropylene composite (70:30 weight ratio). The addition of polypropylene to the composite membrane showed a decrease in the flow rate of back diffused water from cathode to anode giving rise to a steadier water content (water molecules per sulfonic acid group) at the anode required for the efficient distribution of proton concentration. The polypropylene used in the membrane decreases the cost of the membrane. However the low performance of the composite membrane should be addressed. The effect of adding (i) sulfonated phenethyltrimethoxysilane (s-PETMS) and (ii)charged meltblown polypropylene (MBPP) to Liquion® on the performance of composite polymer electrolyte membrane (CPEM) was investigated. The COMSOL multiphysics software was used to model the water concentration inside the membrane based on Fick's second law. The conductive media equation was applied to show the current density distribution inside the membrane. Experimentally, a composite membrane LPMc, having ratio of s-PETMS:charged meltblown polypropylene (CMBPP): Liquion® as 4.5:40:55.5, showed a 15-20% decrease in the current density compared to the Nafion® membrane. The decrease in current density after 90 minutes was 10-12% for Nafion® membrane and 3-6% for the LPMc polymer electrolyte membranes. Along with time, the percentage increase in water concentration was 2.5- 4.0% for the composite membranes and 8-8.5% for the Nafion® membrane. The modeling results were consistent with the experimental data for the operational temperatures and showed that the presence of charged meltblown polypropylene helped maintain a steady water concentration at the anode surface. The s-PETMS likely increased the ion exchange capacity of the membrane and thus increased the current density. [ABSTRACT FROM AUTHOR]

A multidisciplinary team has developed techniques for the formation and evaluation of fabricated auxetic structures. The trust is to combine our current knowledge of geometry and fabric structural characteristics to engineer auxetic textiles and to determine their properties. We have succeeded in producing functional auxetic textile structures from non-auxetic yarns and the details are given in this Report. [ABSTRACT FROM AUTHOR]

The development of the melt electrospinning model was based on our current solution electrospinning model. Our approach began with the idea that electrospinning is a variation of conventional dry spinning. The notable difference is in the way spinline tensile forces are generated. Once the solution electrospinning model was created, we determined what modifications would be required to create a melt electrospinning model. The major difference with solution electrospinning is the lack of the solvent component in the fiber and thus mass transport would not occur. In order to develop the melt electrospinning model, the fundamental role of electrostatics on fiber diameter reduction was investigated. Parametric studies have indicated the possible role surface charge density plays on the rate of this reduction. [ABSTRACT FROM AUTHOR]

Strain energy method and Castigliano's theorem were applied for modeling. Agreement between the values of Young's modulus of textile stents derived by the strain energy method to those of the experimental is good. Braid structural parameters, i.e., length and width of each diamond trellis, total number of diamond trellises, length of fabric braided in one carrier rotation, and braid inclination angle are formulated. Load-strain curves were obtained by strip testing of textile stents on Instron. The objective of the empirical model was to formulate, quantify, and predict compression force of textile stents. The empirical model is able to predict the compression force of textile stents from any two of the known manufacturing variables. Blood flow with the stent is characterized using ANYSYS. [ABSTRACT FROM AUTHOR]

A multidisciplinary team is engaged in this project of developing techniques for the formation and performance of fabricated auxetic structures. Preliminary work aimed at understanding the operating parameters was marginally successful. Modification of the current warp knitting machine in our laboratory and the use of appropriately engineered yarns are in progress and a new research scholar will join the project to deal with the detailed fabrication issues. [ABSTRACT FROM AUTHOR]

A multidisciplinary team has been assembled to develop techniques to melt electrospin polymer nanofibers. On several occasions now we have successfully melt electrospun samples of PP, obtaining nanofibers, albeit only a small percentage of the sample was nanofiber. A crude, heated chamber was used to keep the jet from prematurely solidifying; however, other principles will also be drawn upon to promote the very high attenuation required in melt electrospinning nanofibers. For example, various salts will be added to the polymers to enhance the necessarily larger drawing forces required for melt vs solution electrospinning. We have designed and built a new melt electrospinning apparatus that was developed with input from both fiber formation theory and knowledge we gleaned from our previous apparatuses. The new apparatus uses downward laminar flow of preheated air in a chamber that contains only heat resistant dielectric materials so as to not disturb the electric field established by needle and collector. Developoment of a first-principles-based model for melt electrospinning is proceeding on time. [ABSTRACT FROM AUTHOR]

The electrical characterization of the air/hydrogen polymer electrolyte membrane fuel cell is done. The effect of hydrogen flow rate on voltage, resistance and current is investigated at standard conditions. There is an optimum flow rate that gives the maximum voltage and current. The effect of load on thickness and resistivity of various gas diffusion layers (GDL) is measured. Loading reduces the thickness and resistivity of the GDLs. New GDL structures are being made with wet-lay process. A low cost composite polymer electrolyte membrane was developed. It can increase the fuel cell durability when operated at below 80°C. The polymer electrolyte membrane was prepared from Nafion®/polypropylene composite (70:30 weight ratio). The addition of polypropylene to the composite membrane showed a decrease in the flow rate of back diffused water from cathode to anode giving rise to a steadier water content (water molecules per sulfonic acid group) at the anode required for the efficient distribution of proton concentration. The polypropylene used in the membrane decreases the cost of the membrane. However the low performance of the composite membrane should be addressed. A computational model was established using COMSOL package to simulate the current density distribution and the water management in the Nafion® 117 membrane and Liquion® LQ-1115/polypropylene composite membrane operating at 20°C. The modeling results were validated with experimental data attained using a single fuel cell kit for the polymer electrolyte membranes. [ABSTRACT FROM AUTHOR]

Strain energy method and Castigliano's theorem were applied for modeling. Agreement between the values of Young's modulus of textile stents derived by the strain energy method to those of the experimental is good. Braid structural parameters, i.e., length and width of each diamond trellis, total number of diamond trellises, length of fabric braided in one carrier rotation, and braid inclination angle are formulated. Load-strain curves were obtained by strip testing of textile stents on Instron. The objective of the empirical model was to formulate, quantify, and predict compression force of textile stents. The empirical model is able to predict the compression force of textile stents from any two of the known manufacturing variables. Blood flow with the stent is characterized using ANYSYS. [ABSTRACT FROM AUTHOR]