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Anomaly detection approaches of energy storage systems using Kalman filter and machine learning techniques
Get PDFThe increasing prevalence of cyber-attacks poses a significant concern, particularly within critical infrastructures like the power system. Such attacks have the potential to cause substantial impacts on essential services, economic stability, and national security. Energy storage systems (ESS) are integral components of the power grid and are particularly vulnerable to cyber threats. These vulnerabilities can be exploited through various means, including two-way communication, web portals, and remote access.
Given the critical nature of ESS, the ability to detect and mitigate malicious cyber-attacks is imperative. Various methods can be employed for cyber-attack detection, including signature-based, anomaly-based, and behavior-based approaches. In this study, we focus on two distinct methodologies for anomaly detection related to cyber intrusions on ESS: a physics-based model utilizing a Kalman filter (KF) approach and a data-driven prediction approach employing machine learning (ML) tools.
The main aim of this research is to assess the vulnerability of ESS to cyber threats and evaluate the effectiveness of the KF and ML approaches for cyber protection. By comparing and contrasting these methodologies, we aim to gain insights into their respective strengths and weaknesses, ultimately contributing to enhancing the security of energy storage systems against cyber intrusions
Processing of NiTi SMA for high reflectivity applications
Get PDFNickel Titanium (NiTi) is a shape memory alloy (SMA) that is capable of being deformed and subsequently returned to the original shape through heating. This unique property makes NiTi a prime material for potential applications in the aerospace industry. As manufacturing capabilities advance, the ability to produce and implement advanced materials, such as shape memory alloys like NiTi, becomes more feasible. One such application being studied is deployable mirrors for imaging satellites. Reflector and mirror surfaces for imaging in the visible and infra-red range of the light spectrum require low surface roughness across the largest allowable area for the collection of photons. Monolithic, single piece, mirrors and reflector surfaces for in-space imaging are overly heavy and occupy too much volume in the launch vehicle, as they cannot be folded or separated for stowage. The prospect of deployable mirrors made of polished sheets of SMA offers the possibly of significant weight and volume saving for future imaging satellites. Unlike monolithic mirrors, mirrors composed of SMA may be folded to reduce size while in transit and returned to shape once deployed in space. Imaging surfaces require high specular reflectivity to direct photons towards a central detector. Specular reflectivity of a metallic surface is achieved through creating a surface of appropriate surface roughness. This thesis presents a method of sequential grinding, polishing, shape setting, and vapor deposition coating to produce a NiTi SMA sheet with a surface roughness, Sa, of \u3c 50 nm to achieve 95% reflectivity for the range of 1000-1500 nm. The surface roughness metric is established through the optical convention of wavelength divided by 20. The purpose is to determine if a sheet of shape memory NiTi with a reflective coating can be a viable alternative to current conventional monolithic and multi-piece satellite imaging reflectors. A polishing procedure was developed for an industrial computer numerical control (CNC) milling machine to smooth the surface and minimize the surface roughness. To achieved the reflectivity parameters, a thin film of reflective metal, aluminum, was deposited onto the surface with magnetron sputtering physical vapor deposition (PVD). The samples were characterized using laser scanning microscopy and an integrating sphere equipped ultra-violet, visible, infrared spectrometer device. The samples were characterized as fabricated, and then after introducing a deformation with a radius of curvature of 2 cm, exceeding that estimated 3 cm for a stowed imaging mirror. The resulting data showed that the coated NiTi SMA samples meet the proposed performance requirements, thus demonstrating the capability of NiTi as a viable alternative to current satellite mirror materials
Explosion of Joy in Flight
No full textAcrylic on canvas
36 x 36
Gift of the Artisthttps://digitalcommons.unf.edu/library_art/1088/thumbnail.jp
Tropic of Mischief
No full textAcrylic on canvas
28 1/4 x 46 1/4
Gift of the artisthttps://digitalcommons.unf.edu/library_art/1120/thumbnail.jp
Hasty Angel
No full textwatercolor on paper
9 3/4 x 13 3/4
Gift of Pat Vailhttps://digitalcommons.unf.edu/library_art/1122/thumbnail.jp
Handwritten Note, Christmas Activities at the Duval County Prison Farm
Get PDFNote: Handwritten note recounting Christmas activities at the Duval County Prison Farm. Written on Eartha M. M. White stationary presumed written by Eartha White. Undated
Newsclipping, Negro Prisoners Decrease
Get PDFNews clipping: Article regarding eight per cent decrease of prisoners since the enactment of the prohibition laws. Undated
Silver Fox (for Shirley) 1
No full textAcrylic paint on Plexiglas
36 x 60, left side of diptych
Gift of the Artisthttps://digitalcommons.unf.edu/library_art/1127/thumbnail.jp
The Offering
No full textOil on Canvas
20 x 16
Gift of at Vailhttps://digitalcommons.unf.edu/library_art/1065/thumbnail.jp
UNF Lake II
No full textFlex-a-Rock™, molding epoxy, latex acrylic and glazes on Japanese Maple panels
48 x 96
Gift of the Artisthttps://digitalcommons.unf.edu/library_art/1107/thumbnail.jp