Publications by authors named "Po-Yen Lai"

This research proposes a simulation-based assessment of outdoor thermal and acoustic comfort for a planned business urban district in Singapore for retail planning using a customized OpenFOAM-centric multi-physics environmental simulation platform called the Integrated Environmental Modeller (IEM). IEM was employed to simulate the coupled impacts of solar radiation on wind and air temperature and wind and air temperature effects on traffic noise propagation in the district on the equinox and solstice day of the hottest period. Using IEM simulation results, we computed the thermal and acoustic comfort acceptability indicators derived from local field studies' results.

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Article Synopsis
  • This paper explores how UV-C LED light can effectively inactivate SARS-CoV-2 on surfaces, utilizing a custom-built ray-tracing simulator for this purpose.
  • The simulator is validated against real experiments and a commercial software program, confirming its reliability and user-friendliness for modeling UV-C applications.
  • The study includes a practical example involving a food court in Singapore to analyze how environmental factors impact the effectiveness of UV-C irradiation in eliminating the virus, ultimately offering guidance for the efficient design of UV-C systems.
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The multipass scheme for a diode-seeded fiber master oscillator power amplifier with a nanojoule-to-millijoule output energy level at a repetition rate of <100  kHz is numerically analyzed for comparison to an experimental benchmark. For a 6/125 single-mode preamplifier with a small input energy (<1  nJ), there is a significant improvement in the output energy from 0.7% to 80% and 95% of the maximum extractable energy using the double-pass and four-pass schemes, respectively.

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