In this paper, rapid freezing and thawing test of air-entrained fly–ash concrete was carried out. Gas adsorption of concrete pores, mass loss, dynamic elastic modulus, and chloride diffusion coefficient of concrete after different freezing and thawing cycles was tested; scanning electron image was used to study the microscopic pore structure of the specimens. Results show that after certain fre...

National Institute of Standards and Technology, Gaithersburg, MD 20899-0001 We present quantum scattering calculations for the collisional relaxation rate coefficient of spin-polarized Rb(f = 2,m = 2) atoms, which determines the loss rate of cold Rb atoms from a magnetic trap. Unlike the lighter alkali atoms, spin-polarized Rb atoms can undergo dipolar relaxation due to both the normal spin-spi...

Abstract Energetic electron populations can substantially modify the neoclassical transport properties in stellarators. A model accounting for this change in transport is developed assuming the presence of electron cyclotron resonance heating (ECRH). The quasilinear diffusion coefficient for second harmonic X-mode ECRH is developed for a bumpy stellarator. Care is taken in accounting for the pi...

Reference points and loss aversion are two essential and commonly used concepts in behavioral economics. In this paper, based on insight of Loewenstein’s (1988) reference point model, we construct a structural model for intertemporal choice with reference points and loss aversion by considering four scenarios: delay of gains, delay of losses, speed-up of gains, and speed-up of losses. We use pa...

Design models of multi- stage, axial flow compressor are developed for gas turbine engines. Axial flow compressor is one of the most important parts of gas turbine units. Therefore, its design and performance prediction are very important. One-dimensional modeling is a simple, fast and accurate method for performance prediction of any type of compressors with different geometries. In this appro...

Hundreds of billions of dollars have been spent in homeland security since September 11, 2001. Many mathematical models have been developed to study strategic interactions between governments (defenders) and terrorists (attackers). However, few studies have considered the tradeoff between equity and efficiency in homeland security resource allocation. In this article, we fill this gap by develo...

Criegee intermediates are important species formed during the ozonolysis of alkenes. Reaction of stabilized Criegee intermediates with various species like SO2 and NO2 may contribute significantly to tropospheric chemistry. In the laboratory, self-reaction can be an important loss pathway for Criegee intermediates and thus needs to be characterized to obtain accurate bimolecular reaction rate c...