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Recent new constructions of rate-1 OT [Döttling, Garg, Ishai, Malavolta, Mour, and Ostrovsky, CRYPTO 2019] have brought this primitive under the spotlight and the techniques have led to new feasibility results for private-information retrieval, and homomorphic encryption for branching programs. The receiver communication of this construction consists of a quadratic (in the sender's input size) number of group elements for a single instance of rate-1 OT. Recently [Garg, Hajiabadi, Ostrovsky, TCC 2020] improved the receiver communication to a linear number of group elements for a single string-OT. However, most applications of rate-1 OT require executing it multiple times, resulting in large communication costs for the receiver. In this work, we introduce a new technique for amortizing the cost of multiple rate-1 OTs. Specifically, based on standard pairing assumptions, we obtain a two-message rate-1 OT protocol for which the amortized cost per string-OT is asymptotically reduced to only four group elements. Our results lead to significant communication improvements in PSI and PIR, special cases of SFE for branching programs. - PIR: We obtain a rate-1 PIR scheme with client communication cost of $O(\lambda\cdot\log N)$ group elements for security parameter $\lambda$ and database size $N$. Notably, after a one-time setup (or onemore »PIR instance), any following PIR instance only requires communication cost $O(\log N)$ number of group elements. - PSI with unbalanced inputs: We apply our techniques to private set intersection with unbalanced set sizes (where the receiver has a smaller set) and achieve receiver communication of $O((m+\lambda) \log N)$ group elements where $m, N$ are the sizes of the receiver and sender sets, respectively. Similarly, after a one-time setup (or one PSI instance), any following PSI instance only requires communication cost $O(m \cdot \log N)$ number of group elements. All previous sublinear-communication non-FHE based PSI protocols for the above unbalanced setting were also based on rate-1 OT, but incurred at least $O(\lambda^2 m \log N)$ group elements.« less

The Arctic atmosphere and subauroral region are a natural laboratory for understanding plasma-neutral and dynamical coupling in the atmosphere and geospace. During geomagnetically active periods the auroral electrojet and auroral precipitation are overhead at the High-Frequency Active Auroral Research Program (HAARP) facility in Gakona, Alaska (62°N, 145°W) and facilitate active experiments. Iron resonance lidar systems are uniquely suited for these active investigations as naturally occurring iron layers extend from the upper mesosphere to the middle thermosphere (~70-150 km). A novel lidar system has been demonstrated at the German Aerospace Center using an Nd:YAG laser that operated at a minor line at 1116 nm and was tripled to the iron resonance line at 372 nm. This prototype laser was fully solid-state without liquid dyes or flashlamps and with diode pumping. We are developing a lidar system based on this prototype system that can operate robustly at the remote location of HAARP. We will employ a diode-pumped Nd:YAG laser with second and third harmonic generation. The laser will be injection-seeded by a tunable diode laser allowing the laser to frequency scan the iron line. The laser pulse spectra will be recorded on a shot-by-shot basis using an etalon imaging system with amore »spectral reference. The lidar system is will operate at 372 nm, with a pulse repetition rate of 100 pps, a pulse energy of 30 mJ, and a 0.9-m diameter telescope. We present the system specifications and the expected performance of the system.« less

The Arctic atmosphere and subauroral region are a natural laboratory for understanding plasma-neutral and dynamical coupling in the atmosphere and geospace. During geomagnetically active periods the auroral electrojet and auroral precipitation are overhead at the High-Frequency Active Auroral Research Program (HAARP) facility in Gakona, Alaska (62°N, 145°W) and facilitate active experiments. Iron resonance lidar systems are uniquely suited for these active investigations as naturally occurring iron layers extend from the upper mesosphere to the middle thermosphere (~70-150 km). A novel lidar system has been demonstrated at the German Aerospace Center using an Nd:YAG laser that operated at a minor line at 1116 nm and was tripled to the iron resonance line at 372 nm. This prototype laser was fully solid-state without liquid dyes or flashlamps and with diode pumping. We are developing a lidar system based on this prototype system that can operate robustly at the remote location of HAARP. We will employ a diode-pumped Nd:YAG laser with second and third harmonic generation. The laser will be injection-seeded by a tunable diode laser allowing the laser to frequency scan the iron line. The laser pulse spectra will be recorded on a shot-by-shot basis using an etalon imaging system with amore »spectral reference. The lidar system is will operate at 372 nm, with a pulse repetition rate of 100 pps, a pulse energy of 30 mJ, and a 0.9-m diameter telescope. We present the system specifications and the expected performance of the system.« less

In the context of parallel applications, communication is a critical part of the infrastructure and a potential bottleneck. The traditional approach to tackle communication challenges consists of redesigning algorithms so that the complexity or the communication volume is reduced. However, there are algorithms like the Fast Fourier Transform (FFT) where reducing the volume of communication is very challenging yet can reap large benefit in terms of time-to-completion. In this paper, we revisit the implementation of the MPI all-to-all routine at the core of 3D FFTs by using advanced MPI features, such as One-Sided Communication, and integrate data compression during communication to reduce the volume of data exchanged. Since some compression techniques are ‘lossy’ in the sense that they involve a loss of accuracy, we study the impact of lossy compression in heFFTe, the state-of-the-art FFT library for large scale 3D FFTs on hybrid architectures with GPUs. Consequently, we design an approximate FFT algorithm that trades off user-controlled accuracy for speed. We show that we speedup the 3D FFTs proportionally to the compression rate. In terms of accuracy, comparing our approach with a reduced precision execution, where both the data and the computation are in reduced precision, we show that whenmore »the volume of communication is compressed to the size of the reduced precision data, the approximate FFT algorithm is as fast as the one in reduced precision while the accuracy is one order of magnitude better.« less

Artificial Intelligence (AI) bots receive much attention and usage in industry manufacturing and even store cashier applications. Our research is to train AI bots to be software engineering assistants, specifically to detect biases and errors inside AI software applications. An example application is an AI machine learning system that sorts and classifies people according to various attributes, such as the algorithms involved in criminal sentencing, hiring, and admission practices. Biases, unfair decisions, and flaws in terms of the equity, diversity, and justice presence, in such systems could have severe consequences. As a Hispanic-Serving Institution, we are concerned about underrepresented groups and devoted an extended amount of our time to implementing “An Assure AI” (AAAI) Bot to detect biases and errors in AI applications. Our state-of-the-art AI Bot was developed based on our previous accumulated research in AI and Deep Learning (DL). The key differentiator is that we are taking a unique approach: instead of cleaning the input data, filtering it out and minimizing its biases, we trained our deep Neural Networks (NN) to detect and mitigate biases of existing AI models. The backend of our bot uses the Detection Transformer (DETR) framework, developed by Facebook,