Georgia Tech-Shenzhen

President Ángel Cabrera's keynote speech
2021-12-28 08:00 - 2022-02-20 17:00 (America/New_York)
Come and watch President Ángel Cabrera’s keynote speech at the 2021 World University Presidents Forum! (Shenzhen, China, December 28, 2021).

Celebration of the first Cohort of MSA Students at GTSI
2021-11-01 20:00 - 21:00 (Asia/Shanghai) | Room 424, Building 6B, International Innovation Valley, Shenzhen, Guangdong, China
Date & Time: Monday, November 1 at 8:00 pm – 9:00 pm (UTC+8)

Place: Room 424, Building 6B, International Innovation Valley, Shenzhen

Speech: Hybrid projection methods with recycling for inverse problems
2021-11-01 16:00 - 17:00 (Asia/Shanghai) | Room 408, Building 6B, International Innovation Valley, Shenzhen, Guangdong, China
Speaker: Jiahua Jiang, Assistant Professor

School of Information Science and Technology; Shanghai Tech University

URL: https://intranet.math.vt.edu/people/jiahua/home.html

Date & Time: Monday, November 1 at 4:00 pm – 5:00 pm (UTC+8)

Place: Room 408, Building 6B, International Innovation Valley, Shenzhen

Title: Hybrid projection methods with recycling for inverse problems

Abstract: Iterative hybrid projection methods have proven to be very effective for solving large linear inverse problems due to their inherent regularizing properties as well as the added flexibility to select regularization parameters adaptively. In this work, we develop Golub-Kahan-based hybrid projection methods that can exploit compression and recycling techniques in order to solve a broad class of inverse problems where memory requirements or high computational cost may otherwise be prohibitive. For problems that have many unknown parameters and require many iterations, hybrid projection methods with recycling can be used to compress and recycle the solution basis vectors to reduce the number of solution basis vectors that must be stored, while obtaining a solution accuracy that is comparable to that of standard methods. If reorthogonalization is required, this may also reduce computational cost substantially. In other scenarios, such as streaming data problems or inverse problems with multiple datasets, hybrid projection methods with recycling can be used to efficiently integrate previously computed information for faster and better reconstruction. Additional benefits of the proposed methods are that various subspace selection and compression techniques can be incorporated, standard techniques for automatic regularization parameter selection can be used, and the methods can be applied multiple times in an iterative fashion. Theoretical results show that, under reasonable conditions, regularized solutions for our proposed recycling hybrid method remain close to regularized solutions for standard hybrid methods and reveal important connections among the resulting projection matrices. Numerical examples from image processing show the potential benefits of combining recycling with hybrid projection methods.

Life @ GT-Shenzhen: Our Students’ Perspective
2017-11-16 11:00 - 11:45 (America/New_York) | Clough Bldg, Rm 280
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ECE Career Fair
2016-01-12 22:00 - 23:00 (America/New_York)
Take advantage of this chance to meet with representatives from both local and national companies to discuss career opportunities specifically related to electrical engineering and computer engineering. Participating companies may have full-time, part-time, co-op, or internship opportunities available at the undergraduate or graduate level.

Related Link:

Information for Recruiters
Information for Students

Michael Kneissl Seminar
2016-01-12 08:00 - 17:00 (America/New_York)
Speaker: Michael Kneissl
Affiliation: Institute of Solid State Physics, Technische Universität Berlin, Berlin, Germany &
Ferdinand-Braun-Institut, Leibniz-Institut für Höchstfrequenztechnik, Berlin, Germany
Topic: Exploring the wavelength limits of AlGaN-based deep UV emitters
This presentation will provide an overview of recent advances in the growth of high quality AlGaN materials by metalorganic vapour phase epitaxy (MOVPE) as well as UV-LED device technologies. We will discuss novel approaches to improve the internal and external quantum efficiency of UV light emitters, including the growth of low defect density AlN layers on sapphire substrates by epitaxial lateral overgrowth (ELO) and low resistance n-AlGaN current spreading layers at aluminium mole fractions exceeding 80%. We will present efficient carrier injection into AlGaN-based LEDs emitting below 240 nm based on Mg-doped Al(Ga)N/AlGaN electron blocking heterostructures and examine advanced methods for light extraction, e.g. by controlling the optical polarization of the emission from deep UV AlGaN quantum wells or by utilizing UV-transparent graphene electrodes. We have been able to realize (In)AlGaN multiple quantum well LEDs in the wavelength range between 340 nm and 230 nm and demonstrate UVB-LED arrays near 310 nm with output powers of more than 50 mW and estimated lifetimes of 10,000 hours. Finally, we will illustrate how today’s UV-LEDs are being already successfully applied in flow cytometry, plant growth lighting and sensing, and how they may impact other applications in the near future like water purification, medical diagnostics, and phototherapy.
