A Feedback‐Controlled Calibrator for Phonograph Pick‐Ups

Data Dictionary: Metadata for Phonograph Records

The creation and maintenance of a metadata data dictionary is essential to large-scale digital repositories. It assists the process of data entry, ensures consistency of records, facilitates semantic compatibility and interoperability between systems, and, most importantly, forms the foundation for efficient and effective information retrieval infrastructure. In this paper we explain in detail ...

Calibrator Design for the COBE

The photometric errors of the external calibrator for the FIRAS instrument on the COBE are smaller than the measurement errors on the cosmic microwave background (CMBR) spectrum (typically 0.02 MJy/sr, 1 σ), and smaller than 0.01% of the peak brightness of the CMBR. The calibrator is a re-entrant cone, shaped like a trumpet mute, made of Eccosorb iron-loaded epoxy. It fills the entire beam of t...

Acoustics and Modeling of Pickups

A New Partial Discharge Measuring System Calibrator

A new PD (partial discharge) measuring system calibrator is described. The device, battery operated, may be used either grounded or in a floating position, and generates securely mains-synchronized impulses by capacitive coupling. It allows the determination of the scale factor k and resolution time Tr in PD measuring systems, and it fulfils the requirements of International Standard IEC 60270....

A versatile compact array calibrator for UHE neutrino acoustic detection

In situ acoustic calibration devices are necessary to assure the optimal performance of sensors and detectors for the acoustic detection of ultra-high energy neutrinos in underwater telescopes. Moreover, they provide evidences for the feasibility evaluation of the technique and for the determination of the entire detector efficiency. Following previous studies related to parametric acoustic sou...