This project deals with the coherence optimization of sensing matrices constructed from sampling points on the sphere. We proposed gradient-based optimization and augmented Lagrangian method to optimize the coherence. A short introduction and summary can be read
here.
Related publications:
- Bangun, A., & Culotta-Lopez, C. (2022), Optimizing Sensing Matrices for Spherical Near-Field Antenna Measurements. IEEE Transactions on Antennas and Propagation.
Accessible arxiv
- Bangun, A., Behboodi, A., & Mathar, R. (2021). Tight bounds on the mutual coherence of sensing matrices for Wigner D-functions on regular grids. Sampling Theory, Signal Processing, and Data Analysis, 19(2), 1–39.
- Bangun, A., Behboodi, A., & Mathar, R. (2020). Sensing matrix design and sparse recovery on the sphere and the rotation group. IEEE Transactions on Signal Processing, 68, 1439–1454. Accessible arxiv
This project is related to the development of ptychography algorithm as well as the modification so that we can have live processing reconstruction. Since this project is still running, the algorithm will be updated gradually. For a short introduction of ptychography can be read
here.
Related publications:
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Bangun, A., Baumeister, P., Clausen, A., Weber, D., Dunin-Borkowski, R. E. (2023). Wigner Distribution Deconvolution Adaptation for Live Ptychography Reconstruction. Microscopy and Microanalysis
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Bangun, A., Melnyk, O., März, B., Diederichs, B., Clausen, A., Weber, D., Filbir, F., Müller-Caspary, K. (2022), Inverse Multislice Ptychography by Layer-wise Optimisation and Sparse Matrix Decomposition. IEEE Transactions on Computational Imaging
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Strauch, A., Weber, D., Clausen, A., Lesnichaia, A., Bangun, A., März, B., Lyu, F. J., Chen, Q., Rosenauer, A., Dunin-Borkowski, R., & others. (2021). Live processing of momentum-resolved STEM data for first moment imaging and ptychography. Microscopy and Microanalysis, 27(5), 1078
We develop a mapping between time-frequency analysis of guitar signals to guitar tablature for tuning and melody detection. Firstly, the Gabor Wavelet method is employed to have a time-frequency representation. Secondly, the mapping technique to the frequency database is used to generate guitar tablature. The current implementation adopts a direct mapping from time-frequency analysis to guitar string and frets position. At the moment, we are developing a method to process live data, as well as machine learning to directly generate guitar tablature.
In this project, we develop an automated broadcast message for the Indonesia Christian Student group in Line messenger, using Line Notify, which is implemented with
crontab command in Linux to automatically execute python command for a reminder, birthday greetings as well as events.
In March 2022, I was invited to contribute a project by
Yayasan Nusantara Sejati as a content expert to help develop data science and machine learning course materials for students in the
3T (Terluar, Tertinggal, Terdepan) area (isolated and left-behind regions) in Indonesia. The main challenge in this project is to deliver the complex fundamental theory of data science and machine learning such that it can be easily grasped. Additionally, a simple python implementation is also provided.