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Acquiring general material appearance with hand-held consumer RGB-D cameras is difficult for casual users, due to the inaccuracy in reconstructed camera poses and geometry, as well as the unknown lighting that is coupled with materials in measured color images. To tackle these challenges, we present a novel technique for estimating the spatially varying isotropic surface reflectance, solely from color and depth images captured with an RGB-D camera under unknown environment illumination. The core of our approach is a joint optimization, which alternates among solving for plausible camera poses, materials, the environment lighting and normals. To refine camera poses, we exploit the rich spatial and view-dependent variations of materials, treating the object as a localization-self-calibrating model. To recover the unknown lighting, measured color images along with the current estimate of materials are used in a global optimization, efficiently solved by exploiting the sparsity in the wavelet domain. We demonstrate the substantially improved quality of estimated appearance on a variety of daily objects.

With the development and optimization of switching power supply for the past few decades, analog control technology has become fairly mature. However, analog control method has its own inherent weaknesses, such as fixed compensation design, which limits the application in multiple occasions. Digital control technology has many unique advantages; such as reprogram ability, reprogram ability, unique noise immunity and so on. Due to these advantages, digital-dominated power management IC becomes the current developing trend. In this dissertation, research and design of digitally controlled DC-DC buck converter are conducted. Firstly, power stage design methodology has been reviewed in detail. Then, parameters of the power stage are calculated based on the specification. For the digital controller design, emulation digital design method has been used; proportional–integral–derivative (PID) control methodology is presented. After the analysis of the system closed loop model in Simulink, PID controller in s-domain is conducted. The controller can be transformed to z-domain directly and digital controller design is completed. Finally, digital intensive buck converter is modeled in Simulink. Master of Science (Electronics)