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Vision-Language Models (VLMs) have emerged as powerful tools for image understanding tasks, yet their practical deployment remains hindered by significant architectural heterogeneity across model families. This paper introduces UVLM…

Machine Learning · Computer Science 2026-03-17 Joan Perez , Giovanni Fusco

The US Naval Research Laboratory (NRL) and the National Radio Astronomy Observatory (NRAO) have collaborated to develop, install, and commission a new commensal system on the Karl G. Jansky Very Large Array (VLA). The VLA Low Band…

Instrumentation and Methods for Astrophysics · Physics 2016-03-11 Tracy Clarke , Namir Kassim , Emil Polisensky , Wendy Peters , Simona Giacintucci , Scott D. Hyman

We describe the design of a correlator system for ground and space-based VLBI. The correlator contains unique signal processing functions: flexible LO frequency switching for bandwidth synthesis; 1 ms dump intervals, multi-rate digital…

We present an all-sky catalog of absolute positions and estimates of correlated flux density of 21,942 compact radio sources determined from processing interferometric visibility data of virtually all very long baseline interferometry…

Instrumentation and Methods for Astrophysics · Physics 2025-01-20 Leonid Petrov , Yuri Y. Kovalev

Massive multiple-input multiple-output (MIMO) is a key enabler for the high data rates required by the sixth-generation networks, yet its performance hinges on effective beam management with low training overhead. This paper proposes an…

Information Theory · Computer Science 2026-02-27 Yijie Bian , Wei Guo , Jie Yang , Shenghui Song , Jun Zhang , Shi Jin , Khaled B. Letaief

The World Space Observatory - Ultraviolet (WSO-UV) space telescope is equipped with high dispersion (55,000) spectrographs working in the 1150-3100 {\AA} spectral range. To evaluate the impact of the design on the scientific objectives of…

Instrumentation and Methods for Astrophysics · Physics 2017-06-13 Pablo Marcos-Arenal , Ana I. Gómez de Castro , Belén Perea Abarca , Mikhail Sachkov

Software spectrometer (SWSpec) developed for spacecraft tracking can be used to assure VLBI signal chain reliability, and phase stability of a VLBI receiver. Testing performed with SWSpec during pre-operations both saves time, and eases the…

Instrumentation and Methods for Astrophysics · Physics 2015-04-10 Minttu Uunila , Juha Kallunki , Guifré Molera Calvés

Despite the promise of Neural Posterior Estimation (NPE) methods in astronomy, the adaptation of NPE into the routine inference workflow has been slow. We identify three critical issues: the need for custom featurizer networks tailored to…

Instrumentation and Methods for Astrophysics · Physics 2023-12-25 Keming Zhang , Joshua S. Bloom , Stéfan van der Walt , Nina Hernitschek

The key challenge in multispectral radiation thermometry is accurately measuring emissivity. Traditional constrained optimization methods often fail to meet practical requirements in terms of precision, efficiency, and noise resistance.…

A review is given on the current status and selected results from large VLBI surveys of compact extragalactic radio sources made between 13 cm and 3 mm wavelengths and covering the entire sky. More than 4200 objects are observed and imaged…

Astrophysics · Physics 2009-07-22 Y. Y. Kovalev

Modern Vision-Language Models (VLMs) remain poorly characterized in multi-step visual interactions, particularly in how they integrate perception, memory, and action over long horizons. We introduce VisGym, a gymnasium of 17 environments…

Computer Vision and Pattern Recognition · Computer Science 2026-01-26 Zirui Wang , Junyi Zhang , Jiaxin Ge , Long Lian , Letian Fu , Lisa Dunlap , Ken Goldberg , XuDong Wang , Ion Stoica , David M. Chan , Sewon Min , Joseph E. Gonzalez

The Gaia celestial reference frame (Gaia-CRF) will benefit from a close assessment with independent methods, such as Very Long Baseline Interferometry (VLBI) measurements of radio stars at bright magnitudes. However, obtaining full…

Instrumentation and Methods for Astrophysics · Physics 2024-03-27 Jingdong Zhang , Bo Zhang , Shuangjing Xu , Niu Liu , Wen Chen , Hao Ding , Pengfei Jiang , Yan Sun , Jinqing Wang , Lang Cui , Shiming Wen , Xiaofeng Mai , Jinling Li , Fengchun Shu , Yidan Huang

With the establishment of the AUT University 12m radio telescope at Warkworth, New Zealand has now become a part of the international Very Long Baseline Interferometry (VLBI) community. A major product of VLBI observations are images in the…

Instrumentation and Methods for Astrophysics · Physics 2011-10-26 Stuart Weston , Tim Natusch , Sergei Gulyaev

In a Wireless Sensor Network (WSN), data manipulation and representation is a crucial part and can take a lot of time to be developed from scratch. Although various visualization tools have been created for certain projects so far, these…

Networking and Internet Architecture · Computer Science 2017-03-09 Anh-Vu Dinh-Duc , The-Hien Dang-Ha , Ngoc-An Lam

This paper describes an implementation of spatial consistency in the NYUSIM channel simulation platform. NYUSIM is a millimeter wave (mmWave) channel simulator that realizes measurement-based channel models based on a wide range of…

Information Theory · Computer Science 2018-09-05 Shihao Ju , Theodore S. Rappaport

Robust and accurate pose estimation is crucial for many applications in mobile robotics. Extending visual Simultaneous Localization and Mapping (SLAM) with other modalities such as an inertial measurement unit (IMU) can boost robustness and…

Very long baseline interferometry (VLBI) is a radio-astronomical technique in which the correlated signal from various baselines is combined into an image of highest angular resolution. Due to sparsity of the measurements, this imaging…

Instrumentation and Methods for Astrophysics · Physics 2023-03-29 Hendrik Müller , Andrei Lobanov

In this paper we describe a new approach for mm-VLBI calibration that provides bona-fide astrometric alignment of the mm-wavelength images from a single source, for the measurement of frequency dependent effects, such as `core-shifts' near…

Instrumentation and Methods for Astrophysics · Physics 2017-01-18 Richard Dodson , María Rioja , Sol Molina , José-Luis Gómez

In this work we present more comprehensive evaluations on our airborne Gimbal mounted inertial measurement unit (IMU) signal simulator which also considers flight dynamic model (FDM). A flexible IMU signal simulator is an enabling tool in…

Robotics · Computer Science 2024-11-05 Alireza Kazemi , Reza Rohani Sarvestani

Future wireless networks are envisioned to provide ubiquitous sensing services, which also gives rise to a substantial demand for high-dimensional non-convex parameter estimation, i.e., the associated likelihood function is non-convex and…

Signal Processing · Electrical Eng. & Systems 2023-10-10 Zhixiang Hu , An Liu , Minjian Zhao