2 research outputs found
Anomaly Detection in RFID Networks
Available security standards for RFID networks (e.g. ISO/IEC 29167) are designed to secure individual tag-reader sessions and do not protect against active attacks that could also compromise the system as a whole (e.g. tag cloning or replay attacks). Proper traffic characterization models of the communication within an RFID network can lead to better understanding of operation under “normal” system state conditions and can consequently help identify security breaches not addressed by current standards. This study of RFID traffic characterization considers two piecewise-constant data smoothing techniques, namely Bayesian blocks and Knuth’s algorithms, over time-tagged events and compares them in the context of rate-based anomaly detection.
This was accomplished using data from experimental RFID readings and comparing (1) the event counts versus time if using the smoothed curves versus empirical histograms of the raw data and (2) the threshold-dependent alert-rates based on inter-arrival times obtained if using the smoothed curves versus that of the raw data itself. Results indicate that both algorithms adequately model RFID traffic in which inter-event time statistics are stationary but that Bayesian blocks become superior for traffic in which such statistics experience abrupt changes
Advanced 3D Electrospinning “Xspin” System: Fabrication of Bifiber Floating Oral Pharmaceutical Scaffolds for Controlled Drug Delivery
Electrospinning has become a widely used and efficient
method for
manufacturing nanofibers from diverse polymers. This study introduces
an advanced electrospinning technique, Xspin - a multi-functional
3D printing platform coupled with electrospinning system, integrating
a customised 3D printhead, MaGIC - Multi-channeled and Guided Inner
Controlling printheads. The Xspin system represents a cutting-edge
fusion of electrospinning and 3D printing technologies within the
realm of pharmaceutical sciences and biomaterials. This innovative
platform excels in the production of novel fiber with various materials
and allows for the creation of highly customized fiber structures,
a capability hitherto unattainable through conventional electrospinning
methodologies. By integrating the benefits of electrospinning with
the precision of 3D printing, the Xspin system offers enhanced control
over the scaffold morphology and drug release kinetics. Herein, we
fabricated a model floating pharmaceutical dosage for the dual delivery
of curcumin and ritonavir and thoroughly characterized the product.
Fourier transform infrared (FTIR) spectroscopy demonstrated that curcumin
chemically reacted with the polymer during the Xspin process. Thermogravimetric
analysis (TGA) and differential scanning calorimetry (DSC) confirmed
the solid-state properties of the active pharmaceutical ingredient
after Xspin processing. Scanning electron microscopy (SEM) revealed
the surface morphology of the Xspin-produced fibers, confirming the
presence of the bifiber structure. To optimize the quality and diameter
control of the electrospun fibers, a design of experiment (DoE) approach
based on quality by design (QbD) principles was utilized. The bifibers
expanded to approximately 10–11 times their original size after
freeze-drying and effectively entrapped 87% curcumin and 84% ritonavir. In vitro release studies demonstrated that the Xspin system
released 35% more ritonavir than traditional pharmaceutical pills
in 2 h, with curcumin showing complete release in pH 1.2 in 5 min,
simulating stomach media. Furthermore, the absorption rate of curcumin
was controlled by the characteristics of the linked polymer, which
enables both drugs to be absorbed at the desired time. Additionally,
multivariate statistical analyses (ANOVA, pareto chart, etc.) were
conducted to gain better insights and understanding of the results
such as discern statistical differences among the studied groups.
Overall, the Xspin system shows significant potential for manufacturing
nanofiber pharmaceutical dosages with precise drug release capabilities,
offering new opportunities for controlled drug delivery applications