SEABED INFRASTRUCTURE DEFENSE ANALYSIS

Traditional fleet operations and technologies are not adequately suited to counter the growing threat to undersea infrastructure from autonomous undersea systems. A cost-effective unmanned and manned system of systems is required to provide defense of this seabed infrastructure. This paper proposes possible system architectures to defend against this emerging threat to include passive barriers and active defense systems. The effectiveness of those candidate systems is evaluated through multiple agent-based modeling simulations of UUV versus UUV engagements. Analysis resulted in two major findings. First, point defense of critical assets is more effective than barrier defense. Second, system design must focus on minimizing the time required to effectively engage and neutralize threats, either through improvement to defensive UUV speed or investment in more UUV docking stations and sensor arrays. Cost analysis suggests that acquisition and operations cost of the recommended defensive system is less than the projected financial impact of a successful attack.http://archive.org/details/seabedinfrastruc1094562767Lieutenant, United States NavyLieutenant, United States NavyLieutenant, United States NavyMajor, Israel Defence ForcesMajor, Republic of Singapore Air ForceMajor, Republic of Singapore Air ForceCaptain, Singapore ArmyLieutenant, United States NavyLieutenant, United States NavyLieutenant, United States NavyMajor, Republic of Singapore Air ForceCaptain, Singapore ArmyCivilian, Ministry of Defense, SingaporeLieutenant, United States NavyLieutenant Commander, United States NavyLieutenant Junior Grade, United States NavyCivilian, Ministry of Defense, SingaporeCivilian, Ministry of Defense, SingaporeMajor, Republic of Singapore Air ForceMajor, United States Marine CorpsMajor, Singapore ArmyApproved for public release; distribution is unlimited

Implementation and performances of the IPbus protocol for the JUNO Large-PMT readout electronics

The Jiangmen Underground Neutrino Observatory (JUNO) is a large neutrino detector currently under construction in China. Thanks to the tight requirements on its optical and radio-purity properties, it will be able to perform leading measurements detecting terrestrial and astrophysical neutrinos in a wide energy range from tens of keV to hundreds of MeV. A key requirement for the success of the experiment is an unprecedented 3% energy resolution, guaranteed by its large active mass (20 kton) and the use of more than 20,000 20-inch photo-multiplier tubes (PMTs) acquired by high-speed, high-resolution sampling electronics located very close to the PMTs. As the Front-End and Read-Out electronics is expected to continuously run underwater for 30 years, a reliable readout acquisition system capable of handling the timestamped data stream coming from the Large-PMTs and permitting to simultaneously monitor and operate remotely the inaccessible electronics had to be developed. In this contribution, the firmware and hardware implementation of the IPbus based readout protocol will be presented, together with the performances measured on final modules during the mass production of the electronics

Mass testing of the JUNO experiment 20-inch PMTs readout electronics

The Jiangmen Underground Neutrino Observatory (JUNO) is a multi-purpose, large size, liquid scintillator experiment under construction in China. JUNO will perform leading measurements detecting neutrinos from different sources (reactor, terrestrial and astrophysical neutrinos) covering a wide energy range (from 200 keV to several GeV). This paper focuses on the design and development of a test protocol for the 20-inch PMT underwater readout electronics, performed in parallel to the mass production line. In a time period of about ten months, a total number of 6950 electronic boards were tested with an acceptance yield of 99.1%

Validation and integration tests of the JUNO 20-inch PMTs readout electronics

The Jiangmen Underground Neutrino Observatory (JUNO) is a large neutrino detector currently under construction in China. JUNO will be able to study the neutrino mass ordering and to perform leading measurements detecting terrestrial and astrophysical neutrinos in a wide energy range, spanning from 200 keV to several GeV. Given the ambitious physics goals of JUNO, the electronic system has to meet specific tight requirements, and a thorough characterization is required. The present paper describes the tests performed on the readout modules to measure their performances.Comment: 20 pages, 13 figure

Lanthanide-Doped Energy Cascade Nanoparticles: Full Spectrum Emission by Single Wavelength Excitation

We describe the use of a layer-by-layer hierarchical nanostructure to exploit the synergy of different lanthanide ions for converting single wavelength excitation into emissions spanning the whole spectral region. By lining up a set of lanthanide ions with matched energy levels in a core–shell nanostructure, we demonstrate well-defined cascades of energy transfer that gives access to optical emissions from a large collection of lanthanide ions (Tb³⁺, Eu³⁺, Dy³⁺, Sm³⁺, Nd³⁺, Yb³⁺, and Er³⁺) after excitation into a common sensitizer of Ce³⁺ featuring a broad absorption. Through optimization of the nanoparticle structure and surface coating, high quantum yields of up to 90% are achieved. Our results highlight that the controlled energy cascades at nanometer scale provide new opportunities for applications such as fighting against counterfeiting and sensing small molecules