Uniform Foundation Research Articles

Contextual modal type theory

The intuitionistic modal logic of necessity is based on the judgmental notion of categorical truth. In this article we investigate the consequences of relativizing these concepts to explicitly specified contexts. We obtain contextual modal logic and its type-theoretic analogue. Contextual modal type theory provides an elegant, uniform foundation for understanding metavariables and explicit substitutions. We sketch some applications in functional programming and logical frameworks.

Influence of foundation and axial force on the vibration of thin beam under variable harmonic moving load

The influence of foundation and axial force on the vibration of a simply supported thin (Bernoulli Euler) beam, resting on a uniform foundation, under the action of a variable magnitude harmonic load moving with variable velocity is investigated in this paper. The governing equation is a fourth order partial differential equation. For the solution of this problem, in the first instance, the finite Fourier sine transformation is used to reduce the equation to a second order partial differential equation. The reduced equation is then solved using the Laplace transformation. Numerical analysis shows that the transverse deflection of the thin beam, resting on a uniform foundation, under the action of a variable magnitude harmonic load moving with variable velocity decreases as the foundation constant increases. It also shows that as the axial force increases, the transverse deflection of the thin beam decreases. Journal of the Nigerian Association of Mathematical Physics Vol. 9 2005: pp. 143-150

Similar Background of Graft-Versus-Host Disease (GVHD) Following Allogeneic Blood and Marrow Transplantation (Tx) in Korean and Japanese Populations Allows a Uniform Foundation To Perform Large-Scale Clinical Studies in the Region.

Background: Although it has been reported that the incidence of acute GVHD (aGVHD) and early non-relapse mortality (NRM) after HLA-identical sibling BMT are different between Japanese and other ethnicities, including white American, African American and Irish populations (Oh, Blood.2005), there has been no previous comparison among Asian countries.Patients and Methods: We retrospectively surveyed the data of 1933 patients (pts) (996 Korean and 937 Japanese) who underwent allo-Tx for leukemia or MDS between Jan, 2000 and Dec, 2005. The median age of the pts was 37 yrs (range, 16–70; 34 yrs vs 43 yrs, respectively) and the median follow-up of surviving pts was 1046 days (11–2435). Unexpectedly, the pts' backgrounds, including age, underlying disease, disease status at Tx, stem cell source, donor type, No. of HLA-mismatched (MM) antigen/allele, conditioning regimen, in vivo T-cell depletion with ATG or Campath-1H and GVHD prophylaxis were significantly different between the two groups.Results: (Table) In a multivariate analysis, Tx from a serologically HLA-1-antigen MM donor, Tx from an unrelated donor (URD), pts with high-risk disease at Tx, no in vivo T-cell depletion and a conditioning regimen that included TBI ≥ 10 Gy were associated with an increased risk of grade II–IV aGVHD. Overall, race was not a risk factor for grade II–IV (P=0.19) or III–IV (P=0.98) aGVHD. The incidence of chronic GVHD (cGVHD) in Japanese was significantly lower than that in Korean (P=0.016). In a multivariate analysis, Tx from a genetically HLA-allele MM donor, Tx from an URD, pts with performance status 2–4 at Tx, pts with high-risk disease at Tx, pts with ALL, female to male Tx and pts' age ≥ 40 yrs were associated with poor OS. Race was not a risk factor for OS. The incidence of relapse adjusted for the underlying disease status was associated with grade II–IV aGVHD (RR 0.75, 95% CI 0.61–0.94, P=0.010), but not cGVHD (P=0.63).Conclusions: Despite their different medical backgrounds, our data confirmed that the biology of GVHD is very similar between these two Asian populations, and this provides a uniform foundation for large-scale clinical studies in the region.Korean (n=996)Japanese (n=937)Grade II–IV/III–IV aGVHD37%/15%44%/19%Median onset of aGVHDday 28day 21cGVHD60%47%3-yr OS in standard/high risk70%/42%65%/41%NRM25%30%Relapse25%24%

Variable Velocity Influence on the Vibration of Simply Supported Bernoulli - Euler Beam Under Exponentially Varying Magnitude Moving Load

The variable velocity influence on the vibration of a simply supported Bernoulli-Euler beam, resting on a uniform foundation, under the action of an exponentially varying magnitude load moving with variable velocity is investigated in this work. The technique is based on the Finite Fourier Sine transformation and the Finite Difference method. Numerical results in plotted curves are presented. It is observed from the plotted curves that, when the foundation modulli ‘K’ and the axial force ‘N’ are fixed, the transverse deflections of the beam under load moving with variable velocity are higher than the deflections when the load moves with constant velocity. It is also observed that the response amplitudes in both cases of variable velocity and constant velocity decrease both with increasing ‘K’ and with increasing ‘N’. Also, the analysis shows that the effects of the foundation modulli ‘K’ and the axial force ‘N’ are more pronounced in the vibration of the beam under load moving with variable velocity than in the case when the load moves with constant velocity, hence more reinforcement is needed when the load moves with variable velocity.

Molecular vibrations of [n]oligoacenes (n=2−5 and 10) and phonon dispersion relations of polyacene

As model compounds for nanosize carbon clusters, the phonon dispersion curves of polyacene are constructed based on density functional theory calculations for [n]oligoacenes (n=2-5, 10, and 15). Complete vibrational assignments are given for the observed Fourier-transform infrared and Raman spectra of [n]oligoacenes (n=2-5). Raman intensity distributions by the 1064-nm excitation are well reproduced by the polarizability-approximation calculations for naphthalene and anthracene, whereas several bands of naphthacene and pentacene at 1700-1100 cm(-1) are calculated to be enhanced by the resonance Raman effect. It is found from vibronic calculations that the coupled a(g) modes between the Kekulé deformation and joint CC stretching give rise to the Raman enhancements of the Franck-Condon type, and that the b(3g) mode corresponding to the graphite G mode is enhanced by vibronic coupling between the (1)L(a)((1)B(1u)) and (1)B(b)((1)B(2u)) states. The phonon dispersion curves of polyacene provide a uniform foundation for understanding molecular vibrations of the oligoacenes in terms of the phase difference. The mode correlated with the defect-sensitive D mode of the bulk carbon networks is also found for the present one-dimensional system.

Risk assessment of an interacting structure–soil system due to liquefaction

The present study deals with the non-linear stochastic dynamic analysis of a soil–structure interacting system. The ultimate objective is to determine the risk of damage to the system due to liquefaction under a wide range of earthquake intensities. A Monte Carlo simulation approach is followed in conjunction with advanced finite element procedures. The stochastic spatial variability of soil properties and the randomness of the seismic excitation are taken into account in order to estimate the statistics of the response, measured in terms of uniform foundation settlement and tilting. Specifically, soil properties are modelled as non-Gaussian random fields and seismic excitations as non-stationary random processes. The probabilistic characteristics of the stochastic field modelling soil properties are established from in situ tests. The risk of damage to the soil–structure system due to liquefaction is assessed by establishing fragility curves, which are of paramount importance for risk assessment and management studies of such systems. Fragility curves express the probability of exceeding various thresholds in the response. The relative effect of the variability of various soil parameters on the variability of the response is also examined. Copyright © 2002 John Wiley & Sons, Ltd.

Risk assessment of an interacting structure–soil system due to liquefaction

AbstractThe present study deals with the non‐linear stochastic dynamic analysis of a soil–structure interacting system. The ultimate objective is to determine the risk of damage to the system due to liquefaction under a wide range of earthquake intensities. A Monte Carlo simulation approach is followed in conjunction with advanced finite element procedures. The stochastic spatial variability of soil properties and the randomness of the seismic excitation are taken into account in order to estimate the statistics of the response, measured in terms of uniform foundation settlement and tilting. Specifically, soil properties are modelled as non‐Gaussian random fields and seismic excitations as non‐stationary random processes. The probabilistic characteristics of the stochastic field modelling soil properties are established from in situ tests. The risk of damage to the soil–structure system due to liquefaction is assessed by establishing fragility curves, which are of paramount importance for risk assessment and management studies of such systems. Fragility curves express the probability of exceeding various thresholds in the response. The relative effect of the variability of various soil parameters on the variability of the response is also examined. Copyright © 2002 John Wiley & Sons, Ltd.

Some perspectives on mathematical aspects of artificial intelligence: Logic versus approximation

In the first decades of AI the logical point was dominating in many ways. On the other hand, it was clear that questions connected with common sense have been difficult to grasp by logic and hence alternative techniques (like soft computing) have been developed. In some sense, truth was no longer achieved but approximated. Here we propose to work on rigorous, systematic and uniform mathematical foundations for the various approaches which have been or are currently being developed in this area.

On Resonance of an Infinite Beam on Uniform Elastic Foundation

The transverse steady-state oscillations of an infinite beam, resting on uniform elastic foundation and subjected to a steadily moving harmonic force, are considered. An explicit expression for the exciting force speed dependence on the force frequency, corresponding to the beam infinite response, is obtained.

The dynamical analysis of a finite inextensible beam with an attached accelerating mass

The objective of this paper is an analytical and numerical study of the dynamics of a beam with attached masses. Specifically, a finite inextensible beam that rests on a uniform elastic foundation and carries an accelerating mass is considered. Of interest is the dynamics of the beam-mass system due to the motion of the moving mass. The influence of various parameters such as forward force, retard force and friction upon the performance of the beam are investigated. The mechanics of the problem is Newtonian. Based on the assumption that when the moving mass is set in motion the mass is assumed to be rolling on the beam, the mechanics, including effects due to friction and convective accelerations of the interface between the moving mass and the beam, are determined. The problem of the system is nonlinear, due to the presence of friction and the convective acceleration. In the modeling, the mass can be accelerated by a force. Meanwhile, the mass is capable of reducing speed and being brought to a stop at any position on the beam by applying a retard force to the mass and/or increasing the friction between the mass and the beam. The force is assumed to be tangential to the deformed configuration of the beam. By employing the Galerkin procedure, the partial differential equations which describe the transient vibrations of the beam-mass system are reduced to an initial value problem with finite dimensions. The method of numerical integration is used to get convergent solutions.

FORCED OSCILLATIONS OF INFINITE PERIODIC STRUCTURES. APPLICATIONS TO RAILWAY TRACK DYNAMICS

Forced steady-state oscillations of infinite periodic structures, caused by a moving harmonic force, are considered. One can see two periodicities in railway tracks whose periods are equal to the rail length and sleeper spacing, respectively. The first one causes variations in track pliability near rail joints as well as low frequency oscillations of moving vehicles. This allows one to consider the track as a Euler-Bernoulli beam, resting on uniform visco-elastic foundation. Resilient hinges present rail joints in the track model. The second track periodicity is usually considered along with high frequency track excitation. Taking this into account, the more precise model, that presents the rail as a discretely supported Timoshenko beam, is considered. Three discrete support models of different complexity are studied. The first one presents the rail support as a concentrated mass on a spring and a dashpot in parallel. In the second model, the support is a uniform unbending beam on uniform visco-elastic foundation. The sleeper bend is considered in the third support model. The power series method is used to account its bend. An influence of the rail shear deformations and the sleeper bend on the track frequency response is estimated.

Rigid Punch on Stressed Orthotropic Half-Plane With Partial Slip

An orthotropic half-plane carrying a transverse uniaxial stress and loaded perpendicularly on the free edge by a rigid flat punch is considered. Governing integral equations are stated for the unknown contact stresses between the punch and the half-plane. An analytical solution for contact with complete adhesion and a numerical solution with limiting friction, according to the Coulomb friction law, are presented. Besides distributions of contact stresses the numerical results show relations between vertical load, applied uniform foundation stress, coefficient of Coulomb friction, and size of the slip region.

Design of beams, plates and their elastic foundations for uniform foundation pressure

Beams and circular plates on elastic foundations are considered. In some cases, additional elastic supports are present. The stiffness distribution of the foundation is designed so that the pressure on the foundation is uniform. Sometimes the depth of the beam or plate is also varied, with either a piecewise-constant sandwich or solid cross-section, and a global measure of the deflection is minimized. The total stiffness of the foundation and supports is specified, as well as the volume of the structure. In one type of problem, the edges of the structure are displaced downwards; in the other examples, a downward load is applied. Types of loads include a concentrated central load, a uniform load and a parabolic load. The uniform foundation pressure for the resulting design is often substantially lower than the maximum pressure for a corresponding uniform beam or plate on an elastic foundation with uniform stiffness.

Linear Dynamics of a Translating String on an Elastic Foundation

This paper examines the free and forced linear response of a string which is translating across an elastic foundation. Exact solutions are derived for the free vibration of the string which translates between fixed eyelets and across elastic foundations represented by (1) a single interior spring and (2) a uniform step foundation. Results illustrate the dependence of the string natural frequencies and mode shapes on the foundation stiffness, the foundation geometry, and the string translation speed. The forced response of the string to harmonic end excitation is computed in closed form for the case of a complete uniform foundation. A cutoff frequency separates three distinct solution forms. For excitation frequencies below the cutoff frequency, the response amplitude decays exponentially with distance from the driven end.

Simultaneous Optimization of Beams and Their Elastic Foundations for Minimum Compliance

Nonuniform beams on nonuniform elastic foundations are considered. The beams have sandwich cross-sections with cores of negligible stiffness and are subjected to a uniformly distributed load. The total volume of the beam and the total stiffness of the foundation (which may include elastic supports) are specified. Both the cross-sectional area of the beam and the stiffness distribution of the foundation are design functions. They are chosen to minimize the compliance (or, equivalently, the area displaced by the beam deflection function). The calculus of variations is used to derive optimality conditions, and results are obtained for cantilevers and pinned-pinned beams. Several types of solutions are found, involving a single elastic support or a region of uniform foundation bordered at internal locations by elastic supports. In comparison to a reference uniform beam with uniform foundation, the decrease in compliance is significant.

Application of symbolic algebra to the instability of a nonconservative system

This paper deals with flutter buckling of a tapered column resting on a uniform elastic foundation and subjected to a follower force, The Galerkin method is applied, with attendant computations performed by a computer algebra.

Optimal Beam and Plate Foundations for Minimum Compliance

Uniform beams and circular plates on nonuniform elastic foundations are considered. They are subjected to a uniformly distributed load and have various boundary conditions. For a specified total stiffness of the foundation, the distribution of foundation stiffness is determined which minimizes the compliance (i.e., the work done by the applied load). The optimal solutions for the beams consist of either a single elastic support or a region of uniform foundation bounded by elastic supports (except at free ends). For the plates, there is a central, circular region with a uniform foundation, bounded by a circular elastic support. In comparison to a uniform foundation, the decrease in compliance may be substantial.

Cooling Towers on Flexible Foundations

When large cooling towers are placed directly on moderately soft soils or on long piles, the foundation flexibility has a marked influence on tower behavior. Early studies showed that axisymmetric vertical flexibility of the foundations would reduce the capacity of the tower to carry wind loads by the meridional membrane stresses so that the shell would then develop substantial circumferential bending moments over the entire height of the tower. The present paper extends these studies to include nonaxisymmetric foundation stiffness which can arise frequently in practical cases. The method of analysis given here uses a set of soil‐structure interactive equations derived from the principle of virtual work. Displacements and forces are developed by harmonic analysis and the results give the influence of a nonuniform foundation stiffness on the tower behavior. Numerical studies of two typical tower configurations show that, for gravity load it is the variation of foundation stiffness that influences design, while for wind load it is the average uniform foundation stiffness that governs. The method can be used for any axisymmetrical structure.

Dynamic Interaction Aspects of Cable-Stayed Guideways for High Speed Ground Transportation

This paper describes the dynamic considerations in the design of a long span (200 to 600 ft) cable-stayed guideways for future tracked levitated vehicles (TLV’s) which will be used for high speed ground transportation. A design approach is described in which a cable-stayed guideway structure can be synthesized to simulate the behavior of a beam on elastic foundation. This result is achieved by the “cable-tuning” approach, in which the cable stays are selected to achieve an equivalent uniform elastic foundation. The design approach insures that the live load deflection of the trackway beam is manifested as a traveling wave which moves horizontally at the same velocity as the vehicle, thereby minimizing dynamic interaction problems. Parametric results are presented for the dynamic response of a beam on elastic foundation. Optimum cable and tower configurations are developed for this guideway concept and a typical conceptual design is described.

Totalitarianism and Individualism in Psychology

Abstract Totalitarianism and individualism in psychology do not simply reflect two different schools. Rather, they embody entire philosophies which have political ramifications. Indeed, the psychological issues take on significance only when understood in this larger context. Herbert Marcuse devotes a good deal of Negations to an examination of the cultural and philosophical aspects of individualism and totalitarianism. In the lead essay, “The Struggle Against Liberalism in the Totalitarian View of the State,” he describes individualism, or liberalism, in the following manner: “Liberalism was the social and economic theory of European industrial capitalism in the period when the actual economic bearer of capitalism was the ‘individual capitalist,’ the private entrepreneur in the literal sense. Despite structural variations in liberalism and its bearers from one country or period to another, a uniform foundation remains: the individual economic subject's free ownership and control of private property and the politically and legally guaranteed security of these rights.”