Ontario Ministry of Transportation

About: Ontario Ministry of Transportation is a government organization based out in Toronto, Ontario, Canada. It is known for research contribution in the topics: Poison control & Asphalt. The organization has 4652 authors who have published 3882 publications receiving 59011 citations.

Thermal reliability and characterization of InGaP Schottky contact with Ti/Pt/Au metals

Abstract: We present the characteristics of Ti/Pt/Au Schottky contacts on wide bandgap InGaP semiconductors with surface pre-treatment before Schottky contact deposition, and investigate the influence of post heat treatment on Schottky diodes. With the pre-deposition surface etching by dilute HCl, dilute NH4OH, or buffer oxide etchant (BOE), the performance of Schottky diodes compared with samples without surface pre-treatment is improved significantly. Auger electron spectroscopy (AES) analysis of the thermally annealed Schottky diode has been performed to investigate the failure mechanism. No significant change was found for samples annealed up to 450°C. However, a drastic degradation of the barrier height and the ideality factor was observed in samples annealed at 500°C, which may be caused by the interdiffusion and penetration of metals into the semiconductor.

Two seismic gaps on the Sagaing Fault, Myanmar, derived from relocation of historical earthquakes since 1918

Abstract: [1] Relocation of six M (magnitude) ≥ 7.0 earthquakes near the Sagaing Fault in Myanmar since 1918 allows us to image earthquake history along the Sagaing Fault. All the earthquakes were relocated on the Sagaing Fault by using the modified joint hypocenter determination method. Combining the relocated epicenters with information on foreshocks, aftershocks, seismic intensities, and coseismic displacement, we estimated the location of the fault plane that ruptured during each earthquake. This analysis revealed two seismic gaps: one between 19.2°N and 21.5°N in central Myanmar, and another south of 16.6°N in the Andaman Sea. Considering the length of the first seismic gap (∼260 km), a future earthquake of up to M ∼7.9 is expected to occur in central Myanmar. Because Nay Pyi Taw, the recently established capital of Myanmar, is located on the expected fault, its large population is exposed to a significant earthquake hazard.

Extremely small vertical far-field angle of InGaAs-AlGaAs quantum-well lasers with specially designed cladding structure

Abstract: We report on a very small vertical far-field angle achieved by lasers with a specially designed structure. For an InGaAs-AlGaAs quantum-well laser with a 2.5-/spl mu/m-wide ridge waveguide, the far-field pattern has a vertical far-field angle of 13/spl deg/ and a lateral far-field angle of 8/spl deg/. Meanwhile, the threshold current remains acceptably low (/spl ap/36 mA for a 500-/spl mu/m-long cavity). The slope efficiency of the L-I characteristic is high (>0.9 W/A) compared to that of the conventional laser.

Application of the discrete element method and CT scanning to investigate the compaction characteristics of the soil–rock mixture in the subgrade

Abstract: The soil–rock mixture (SRM) usually contains a large amount of gravels exceeding 40 mm in size, so the traditional laboratory method cannot directly test its maximum dry density (MD), making it dif...

Fatigue assessment for deck plates in orthotropic bridge decks

Abstract: Since the 1960s, orthotropic deck plates of highway bridges have been built with large coldformed trapezoidal stiffeners supporting a deck plate with a thickness of approx. 12 mm. The maximum cross-beam spacing is approx. 4 m. A number of these bridge decks in The Netherlands suffer from fatigue cracks in the deck plate. First cracks have been observed after about 30 years in service. In one particular movable bridge, the cracks were found after only seven years. In many other countries, this type of crack has not yet been observed. This article provides a fatigue assessment procedure for deck plates. The procedure is calibrated with the conditions and observations in The Netherlands. It gives a fatigue life prediction and takes account of inspection results quantitatively. Although aspects such as the type and thickness of the surface finishes and the traffic load may vary between countries, the principles of the assessment procedure in this article are generally applicable and can be used to identify reasons for differences in fatigue life and to develop strategies for increasing the life