795 nm oxide-confined distributed feedback (DFB) lasers have been developed. The structure is used to realize lateral optical and current confinement, the first order surface gratings offer frequency selectivity for single longitudinal mode operation. fabricated 200-um-long devices exhibited a low-threshold of ∼4.8 mA, 3-dB modulation bandwidth ∼5.8 GHz maintained stable operation around with s...

The capability of Degree Heating Weeks index (DHWs) was examined for prediction of bleaching events in the coral reef communities of the Kish Island located in the north of the Persian Gulf. In doing so, weekly Sea Surface Temperature (SST) values (in 1°×1° spatial resolution) prepared by National Oceanic and Atmospheric Administration (NOAA), coupled with documented bleaching events, such...

OBJECTIVE To calculate root canal volume and surface area in microCT images, an image segmentation by selecting threshold values is required, which can be determined by visual or automatic methods. Visual determination is influenced by the operator's visual acuity, while the automatic method is done entirely by computer algorithms. To compare between visual and automatic segmentation, and to de...

The electron field emission of tetrahedral amorphous carbon ~ta-C! films deposited by filtered cathodic vacuum arc is reported. The ta-C films were found to have a threshold field ranging from 18 to 28 V mm, depending on the sp content. The nitrogenated ta-C ~ta-C:N! films show a lower threshold field of 12 V mm as compared to the ta-C films. The threshold field appears to be dependent on the f...

The interaction of thermal Ar plasma particles with Si and W surfaces is modeled using classical molecular dynamics (MD) simulations. At plasma energies above the threshold for ablation, the ablation yield can be calculated directly from MD. For plasma energies below threshold, the ablation yield becomes exponentially low, and direct MD simulations are inefficient. Instead, we propose an integr...

Binocular disparity and motion parallax provide information about the spatial structure and layout of the world. Descriptive similarities between the two cues have often been noted which have been taken as evidence of a close relationship between them. Here, we report two experiments which investigate the effect of surface orientation and modulation frequency on (i) a threshold detection task a...

The Propose of this paper is to introduce a new model for crude oil fouling in preheat trains of crude distillation unit. The experimental results of Australian light crude oil with the tube side surface temperatures between 200-260 oC and fluid velocity ranged 0.25 to 0.4m/s were used. The activation energy of chemical reaction depends on the surface temperature has been calcula...