‎The water wave generation by wave paddle and a freely falling rigid body are examined by using an Incompressible Smoothed Particle Hydrodynamics (ISPH)‎. ‎In the current ISPH method‎, ‎the pressure was evaluated by solving pressure Poisson equation using a semi-implicit algorithm based on the projection scheme and the source term of pressure Poisson equation contains both of divergence free ve...

We describe a system for the detection of changes in multiple views of a tunnel surface. From data gathered by a robotic inspection rig, we use a structure-from-motion pipeline to build panoramas of the surface and register images from different time instances. Reliably detecting changes such as hairline cracks, water ingress and other surface damage between the registered images is a challengi...

Seasonal frozen loess tunnel stability is controlled by many factors. To study the effects of water content and freeze-thaw cycles of loess tunnel stability, taking loess in Shanxi Yangqu No. 1 tunnel face as the research object, to do different moisture stability studies on loess tunnel after repeated freeze-thaw cycles. The results show that: (1) by the comprehensive structure potential and s...

Stream water quality in areas of the western United States continues to be degraded by acid mine drainage (AMD), a legacy of hard-rock mining. The Rico-Argentine Mine in southwestern Colorado consists of complex multiple-level mine workings connected to a drainage tunnel discharging AMD to passive treatment ponds that discharge to the Dolores River. The mine workings are excavated into the hill...

successful application of a tbm in a project requires investigating both the ground conditions and the machine and backup system design features. prediction of the machine performance is very important as it has a big effect on the duration of the project and the costs. in this respect, both penetration rate and advance rate must be estimated. utilization factor, which depends on the type of op...

We have developed InGaAs-based VCSELs operating around 1.1 μm for high-speed optical interconnections. By applying GaAsP barrier layers, temperature characteristics were considerably improved compared to GaAs barrier layers. As a result, 25 Gbps 100◦C error-free operation was achieved. These devices also exhibited high reliability. No degradation was observed over 3,000 hours under operation te...

Experiments have been performed to assess the utility of unsteady one-dimensional heat conduction modelling for the calculation of heat losses during a free piston compression process. Heat transfer measurements have been obtained within a gun tunnel barrel using surface junction thermocouple instrumentation. The gun tunnel was operated with a relatively heavy piston such that the shock waves i...

Tunnelling through cities underlain by soft soil, commonly associated with soil movement around the tunnels and subsequent surface settlement. The predication of ground movement during the tunnelling and optimum support pressure could be based on analytical, empirical or the numerical methods. The commonly used Earth pressure balance (EPB) tunneling machines, uses the excavated soil in a pressu...

Passing underground trains induce vibrations transmitted to the ground surface and the nearby structures. Ordinarily, these vibrations do not result in structural damage but can harm nonstructural elements and disturb the occupants. These effects are more pronounced when evaluating buildings like hospitals, laboratories, museums, etc., and their assessment is an important design need. To respon...