The green (537 and 558 nm) and near infrared (1.54 mm) photoluminescence (PL) spectra of Er-doped GaN thin films have been investigated as a function of temperature, excitation wavelength, and pump intensity. Thermal quenching measurements showed that the 31 4 2 4 integrated green Er PL intensity ( S / H → I ) remained nearly constant up to 150 K, but decreased at higher temperatures 3 / 2 11 /...

A b s t r a c t The f i r s t p a r t of t h i s paper g i v e s r e s u l t s about promise problems. A "promise problem" i s a formulation of a p a r t i a l d e c i s i o n problem t h a t i s u s e f u l f o r d e s c r i b i n g cracking problems f o r public-key cryptosystems (PKCS). We prove t h a t every NP-hard promise problem i s uniformly NP-hard, and w e show t h a t a number of r e...

Fruit cracking has long been a topic of great concern for growers and researchers of litchi (Litchi chinensis Sonn.). To understand the molecular mechanisms underlying fruit cracking, high-throughput RNA sequencing (RNA-Seq) was first used for de novo assembly and characterization of the transcriptome of cracking pericarp of litchi. Comparative transcriptomic analyses were performed on non-crac...

The cracking and delamination of TiN-coated hardmetals (WC-Co cemented carbides) when subjected to Brale indentation were studied. Experimental variables were substrate microstructure related to low (6%wt. Co) and medium (13%wt. Co) binder content, and surface finishes associated with grinding and polishing stages before film deposition. Brale indentation tests were conducted on both coated and...

This paper considers the explicit solutions of free-edge stresses near circumferential cracks in surface coatings of circular torsion bars and their application in determining the progressive cracking density in the coating layers. The problem was formulated within the framework of linear elastic fracture mechanics (LEFM). The free-edge stresses near crack tip and the shear stresses in the cros...

Tar removal from biomass gasification gas is a crucial problem in applying syngas from biomass for its downstream applications. Catalytic biomass gasification has given promising results for tar cracking. A few research groups have investigated the use of olivine for tar cracking [2,3,4,7,8,9,10]. The presence of oxides of iron and magnesium in the mineral olivine give it the ability to crack h...

The relation of habitual knuckle cracking to osteoarthrosis with functional impairment of the hand has long been considered an old wives' tale without experimental support. The mechanical sequelae of knuckle cracking have been shown to produce the rapid release of energy in the form of sudden vibratory energy, much like the forces responsible for the destruction of hydraulic blades and ship pro...

Cracking is one of the primary distresses for asphalt pavements. There are many types laboratory tests developed to evaluate cracking performance material, however, relatively little attention has been dedicated evaluating and correlating measured properties with actual pavement performance. The main objective this study investigate relationships between various binder/mixture (including both f...

Parameterized password guessability—how many guesses a particular cracking algorithm with particular training data would take to guess a password—has become a common metric of password security. Unlike statistical metrics, it aims to model real-world attackers and to provide per-password strength estimates. We investigate how cracking approaches often used by researchers compare to real-world c...