The fast development of the light detection and ranging (LiDAR) technique, especially with scanning and multi-beam systems that launch pulses along different directions, requires efficient and accurate simulation tools to analyze existing data and to design future systems. This work presents the recent advantages of the discrete anisotropic radiative transfer (DART) model in LiDAR data simulation. A more comprehensive comparison between DART-simulated waveforms and Laser Vegetation Imaging Sensor (LVIS) over Howland forest, Maine is presented. Results show that in addition to waveform shape simulation, radiometric calibration coefficients could be inferred from the comparison. This new discovery could provide an approach for possible radiometric modeling of LiDAR data, that convert the digital number of the waveform into actual energy.

We introduced an approach to simulate and separate atmospheric contribution in ground-based thermal-infrared (TIR) camera measurements. Different from the traditional approach which uses the look-up table built from 1-D radiative transfer model (RTM), this approach directly simulates 3-D ray propagations and interactions in the heterogeneous urban environment by using the Discrete Anisotropic Radiative Transfer (DART) model. The atmospheric turbid cells that occupy every part of the urban scene are created using the vertical constituent distribution and the optical property profiles in the existing databases or from the actual meteorological measurements. The two components of atmospheric effects on the TIR at-sensor radiance are attenuated transmission and path thermal emission. Taking both into account, the at-surface radiance corresponding to the signal emitted only from the urban surface can be derived.

Commercial buildings increasingly include technologies capable of providing ancillary services to electric power grids. Features include thermal energy storage inherent in building structures that can be coupled to electric grids through heating, ventilating, and air-conditioning (HVAC) systems controlled by variable-speed drives (VSDs). In parking garages, plug-in electric vehicles (PEVs) are connected to the building power lines through charging stations and can be utilized as grid storage. System power electronics can control equipment power demand at frequencies associated with ancillary services procured in electricity markets, where services dispatch over time scales ranging from hours to seconds. Limitations in provision of services by buildings include building-scale thermal and electrical energy storage capacities: thermal comfort of occupants, state of charge of PEV batteries, and the power rating of VSDs and PEV chargers. This paper reviews available technologies and necessary control strategies for HVAC systems in commercial buildings to provide ancillary services. We then develop physically-based scaling metrics for building thermal storage technologies accessible through HVAC systems. In addition, the effect of ancillary services provided by HVAC systems on grid network and electricity market operations is analyzed using simulation case studies, incorporating magnitude scaling of services. We finally evaluate a possibility that the HVAC systems and PEVs provide three-phase voltage and power balance regulation services, respectively.