arXiv subjects

Mohamed El-Hadedy

Publications and source records attributed to Mohamed El-Hadedy.

7 recordsLinked to original sources

arXiv2026

RSCL Earth Lookback Simulator: A Real-Time Multi-Physics Framework for Relativistic Signal Propagation from Confirmed Milky Way Exoplanets

Electromagnetic signals propagating across interstellar distances are subject to simultaneous distortion by seven distinct physical mechanisms: relativistic Doppler shift, stellar aberration, interstellar medium dispersion, special relativistic time dilation, general relativistic gravitational time dilation, cosmological redshift, and atmospheric transmission losses. Each effect is individually well established, yet to our knowledge no existing public browser-based framework applies all seven effects simultaneously to a catalog of confirmed exoplanets using real measured stellar and planetary parameters. This paper presents the RSCL Earth Lookback Simulator, an open-source browser-based framework that addresses this gap. Seven physics engines operate in parallel on a curated catalog of 62 confirmed Milky Way exoplanets, drawing all physical parameters from the NASA Exoplanet Archive and the NE2001 galactic electron density model. Computed quantities are checked for consistency against published reference values. The framework is deployed as a public open-source application and is designed to serve researchers in SETI, exoplanet science, astrobiology, and space mission planning.

astro-ph.EP↗

arXiv2024

Educating for Hardware Specialization in the Chiplet Era: A Path for the HPC Community

The advent of chiplet technology introduces cutting-edge opportunities for constructing highly heterogeneous platforms with specialized accelerators. However, the HPC community currently lacks expertise in hardware development, a gap that must be bridged to leverage these advancements. Additionally, technologies like chiplet is cutting-edge with limited educational resource available. This paper addresses potential hardware specialization direction in HPC and how to cultivate these skills among students and staff, emphasizing the importance of understanding and developing custom hardware (e.g., rapid prototyping and resource estimation). We have been mentoring graduate-level students and new staff in hardware designs in a hands-on manner, encouraging them to utilize modern open-source hardware tools for their designs, which facilitates the sharing of research ideas. Additionally, we provide a summary of theses tools as part of our approach to prototyping and mentoring.

cs.AR↗

arXiv2020

Ensemble Hyperspectral Band Selection for Detecting Nitrogen Status in Grape Leaves

The large data size and dimensionality of hyperspectral data demands complex processing and data analysis. Multispectral data do not suffer the same limitations, but are normally restricted to blue, green, red, red edge, and near infrared bands. This study aimed to identify the optimal set of spectral bands for nitrogen detection in grape leaves using ensemble feature selection on hyperspectral data from over 3,000 leaves from 150 Flame Seedless table grapevines. Six machine learning base rankers were included in the ensemble: random forest, LASSO, SelectKBest, ReliefF, SVM-RFE, and chaotic crow search algorithm (CCSA). The pipeline identified less than 0.45% of the bands as most informative about grape nitrogen status. The selected violet, yellow-orange, and shortwave infrared bands lie outside of the typical blue, green, red, red edge, and near infrared bands of commercial multispectral cameras, so the potential improvement in remote sensing of nitrogen in grapevines brought forth by a customized multispectral sensor centered at the selected bands is promising and worth further investigation. The proposed pipeline may also be used for application-specific multispectral sensor design in domains other than agriculture.

cs.CV↗

arXiv2019

Analysis and Optimization of I/O Cache Coherency Strategies for SoC-FPGA Device

Unlike traditional PCIe-based FPGA accelerators, heterogeneous SoC-FPGA devices provide tighter integrations between software running on CPUs and hardware accelerators. Modern heterogeneous SoC-FPGA platforms support multiple I/O cache coherence options between CPUs and FPGAs, but these options can have inadvertent effects on the achieved bandwidths depending on applications and data access patterns. To provide the most efficient communications between CPUs and accelerators, understanding the data transaction behaviors and selecting the right I/O cache coherence method is essential. In this paper, we use Xilinx Zynq UltraScale+ as the SoC platform to show how certain I/O cache coherence method can perform better or worse in different situations, ultimately affecting the overall accelerator performances as well. Based on our analysis, we further explore possible software and hardware modifications to improve the I/O performances with different I/O cache coherence options. With our proposed modifications, the overall performance of SoC design can be averagely improved by 20%.

cs.AR↗

arXiv2018

ASAP: Accelerated Short-Read Alignment on Programmable Hardware

The proliferation of high-throughput sequencing machines ensures rapid generation of up to billions of short nucleotide fragments in a short period of time. This massive amount of sequence data can quickly overwhelm today's storage and compute infrastructure. This paper explores the use of hardware acceleration to significantly improve the runtime of short-read alignment, a crucial step in preprocessing sequenced genomes. We focus on the Levenshtein distance (edit-distance) computation kernel and propose the ASAP accelerator, which utilizes the intrinsic delay of circuits for edit-distance computation elements as a proxy for computation. Our design is implemented on an Xilinx Virtex 7 FPGA in an IBM POWER8 system that uses the CAPI interface for cache coherence across the CPU and FPGA. Our design is $200\times$ faster than the equivalent C implementation of the kernel running on the host processor and $2.2\times$ faster for an end-to-end alignment tool for 120-150 base-pair short-read sequences. Further the design represents a $3760\times$ improvement over the CPU in performance/Watt terms.

cs.DC↗

arXiv2016

Posting with credibility in Micro-blogging systems using Digital Signatures and Watermarks: A case study on Twitter

Micro-blogs are contemporary broadcasting services for exchanging small elements of content, including video and images. Despite its popularity, micro-blogging is not without issues. So far, various security concerns, such as: privacy and confidentiality of micro-blogging systems have attracted the interest of the scientific community. Nevertheless, in this document we refer to a security issue that is concerned with the posting and circulation of fake messages. With the aim to make micro-blogs a credible source of information, in this work we propose a protocol, as a solution, that can be easily adapted to existing services such as: Twitter and Facebook. With the main keys of the solution being the employment of digital signatures and watermarks, the protocol can serve postings of various types of content. Finally, the solution serves the dual purpose of proofing the fake messages as well as the repudiation of postings.

cs.SI↗

arXiv2013

An Efficient Authorship Protection Scheme for Shared Multimedia Content

Many electronic content providers today like Flickr and Google, offer space to users to publish their electronic media (e.g. photos and videos) in their cloud infrastructures, so that they can be publicly accessed. Features like including other information, such as keywords or owner information into the digital material is already offered by existing providers. Despite the useful features made available to users by such infrastructures, the authorship of the published content is not protected against various attacks such as compression. In this paper we propose a robust scheme that uses digital invisible watermarking and hashing to protect the authorship of the digital content and provide resistance against malicious manipulation of multimedia content. The scheme is enhanced by an algorithm called MMBEC, that is an extension of an established scheme MBEC, towards higher resistance.

cs.MM↗