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The double layer (DL) TFT consists of an IGZO channel layer with no oxygen flow (NOF) and an IGZO barrier layer with oxygen flow (OF). The DL-TFT demonstrates the field-effect mobility of 19 cm2/V-s, which is 1.6X of the NOF and the OF singe-layer TFTs (SL-TFTs) at the overdrive voltage of 18V and the drain voltage of 0.1V. The conduction band difference between NOF and OF IGZO is 0.28 eV, which was obtained by Tauc method, X-Ray photoelectron spectroscopy (XPS), and Kevin probe force microscopy (KPFM). The carriers in the DL-TFT are confined in the NOF layer by quantum confinement, where the OF layer serves as the barrier to reduce the Coulomb scattering between the channel electrons and oxide charge, and the surface roughness scattering from the IGZO/oxide interface. The results of positive bias temperature instability (PBTI) show that the threshold voltage shift of the DL-TFT is between the individual SL-TFT, and the DL-TFT is close to the lower one of the two SL-TFTs.

High-angular resolution diffusion imaging (HARDI) relative to the diffusion tensor imaging (DTI) can resolve the complex fiber crossing of each voxel in the brain, however, the image reconstruction time is longer than conventional technology, therefore, to improve the performance is a very important work to do. We used graphic processing unit (GPU) and CUDA to compute the spherical harmonic function on the reconstruction of QBI. It's very useful on massive performance data (Bid Data). With the large number of matrix elements in GPU for parallel computing. By evaluating with different video cards, the improved performance showed 179 to 574 speed up through shared memory access for computation. Finally, the results will be used in an extension of the three-dimensional spatial visualization and probabilistic tractography.

We proposed a filtered q-ball imaging (fQBI) method for the reconstruction of fiber orientation distribution function (ODF) together with the quantitative comparison to unfiltered QBI. The filter kernel increases the high angular frequency content that is beneficial for the angular resolution in resolving crossing fibers. Through a series of simulations using Monte-Carlo model, the angular resolution of fQBI was demonstrated better than traditional QBI but the deviation of fiber orientation estimate also becomes larger. The improvement of the angular resolution can also reduce the underestimation of separation angles as well as the bias of fiber orientation estimations. In conclusion, fQBI was demonstrated to improve the angular resolution of QBI in resolving crossing fibers. This improvement will be helpful to precisely reconstruct fiber tract and brain network in applications by QBI.

Recently developed methods to resolve multiple fiber orientations within a voxel from high angular resolution diffusion imaging (HARDI) are applied to resolve complex neuronal connectivity. In the study, an extension of multiple streamline tractography was proposed to estimate the probabilistic fiber tracking between brain areas. Multi-fiber component in the conjunction of corticospinal tracts, corpus callosum, and superior longitudinal fasciculus were studied in this study. The extracted results from probabilistic tracking presented the potential to estimate the whole brain map of anatomical connection probability.

Diffusion MRI is a technique that can probe diffusivity of water molecules in brain structure non-invasively and so that it presents complex neuronal orientation by discrete ribbons. In the study, a new tractography algorithm for high angular resolution diffusion imaging was developed to connect the discrete neural orientations and to extract sophisticated neuronal connectivity in human brain. By using volume of interesting selection interface and interaction of multiple regions by Boolean function, the results showed its potential of this technique in revealing complex neuronal pathways which could not be acquired from conventional techniques.