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We study the local eigenvalue statistics $\xi_{\omega,E}^N$ associated with the eigenvalues of one-dimensional, $(2N+1) \times (2N+1)$ random band matrices with independent, identically distributed, real random variables and band width growing as $N^\alpha$, for $0 < \alpha < \frac{1}{2}$. We consider the limit points associated with the random variables $\xi_{\omega,E}^N [I]$, for $I \subset \mathbb{R}$, and $E \in (-2,2)$. For Gaussian distributed random variables with $0 \leq \alpha < \frac{1}{7}$, we prove that this family of random variables has nontrivial limit points for almost every $E \in (-2,2)$, and that these limit points are Poisson distributed with positive intensities. The proof is based on an analysis of the characteristic functions of the random variables $\xi_{\omega,E}^N [I]$ and associated quantities related to the intensities, as $N$ tends towards infinity, and employs known localization bounds of \cite{schenker, peled, et. al.}, and the strong Wegner and Minami estimates \cite{peled, et. al.}. Our more general result applies to random band matrices with random variables having absolutely continuous distributions with bounded densities. Under the hypothesis that the localization bounds hold for $0 < \alpha < \frac{1}{2}$, we prove that any nontrivial limit points of the random variables $\xi_{\omega,E}^N [I]$ are distributed according to Poisson distributions., Comment: We improved Theorem 1.2 from compound Poisson distributions to Poisson distributions in all cases considered. We more clearly highlighted the models to which our results apply

The Dual-Frequency synthetic aperture radar (DFSAR) system manifested on the Chandrayaan-2 spacecraft represents a significant step forward in radar exploration of solid solar system objects. It combines SAR at two wavelengths (L- and S-bands) and multiple resolutions with several polarimetric modes in one lightweight ($\sim$ 20 kg) package. The resulting data from DFSAR support calculation of the 2$\times$2 complex scattering matrix for each resolution cell, which enables lunar near surface characterization in terms of radar polarization properties at different wavelengths and incidence angles. In this paper, we report on the calibration and preliminary performance characterization of DFSAR data based on the analysis of a sample set of crater regions on the Moon. Our calibration analysis provided a means to compare on-orbit performance with pre-launch measurements and the results matched with the pre-launch expected values. Our initial results show that craters in both permanently shadowed regions (PSRs) and non-PSRs that are classified as Circular Polarization Ratio (CPR)-anomalous in previous S-band radar analyses appear anomalous at L-band also. We also observe that material evolution and physical properties at their interior and proximal ejecta are decoupled. For Byrgius C crater region, we compare our analysis of dual-frequency radar data with the predicted behaviours of theoretical scattering models. If crater age estimates are available, comparison of their radar polarization properties at multiple wavelengths similar to that of the three unnamed south polar crater regions shown in this study may provide new insights into how the rockiness of craters evolves with time., Comment: 30 pages, 16 figures; accepted by The Planetary Science Journal

This article presents a primer/overview of applications of Artificial Intelligence and Machine Learning (AI/ML) techniques to address problems in the domain of computer networking. In particular, the techniques have been used to support efficient and accurate traffic prediction, traffic classification, anomaly detection, network management, network security, network resource allocation and optimization, network scheduling algorithms, fault diagnosis and many more such applications. The article first summarizes some of the key networking concepts and a few representative machine learning techniques and algorithms. The article then presents details regarding the availability of data sets for networking applications and machine learning software and toolkits for processing these data sets. Highlights of some of the standards activities, pursued by ITU-T and ETSI, which are related to AI/ML for networking, are also presented. Finally, the article discusses a small set of representative networking problems where AI/ML techniques have been successfully applied., Comment: 38 pages

In this work, ZnO nanowire arrays decorated with titanium nitride (TiN) nanoparticles as surface enhanced Raman scattering (SERS) substrates is demonstrated. ZnO nanowires were grown by hydrothermal synthesis while ~100 nm TiN nanoparticles were obtained by grinding commercial powders for several hours. They were then decorated on the ZnO nanowire arrays using acetone as the medium. Scanning electron microscopy confirmed the presence of TiN nanoparticles on the ZnO nanowires. TiN nanoparticles exhibited localized surface plasmon resonances at 430, 520 and 600 nm. SERS experiments using Nile Blue and Methylene Blue as the analyte molecules showed significant enhancement in the Raman signals. It is shown that the origin of the SERS effect is chemical in nature, due to charge transfer between the analyte molecule and the TiN nanoparticles. The current work, thus, represents a simple, cost-effective and facile method for the fabrication of TiN based surface enhanced Raman scattering substrates.

Copper oxide thin film based metal-insulator-metal structures were subjected to white light irradiation.The top electrodes included Al, Cr and Ni while the bottom electrode was either Au or Pt. A white light pulse controls the set process and this light induced set (LIS) can be performed at very low voltages (tens of milli volts) which is not possible in the normal set process. The LIS is initiated at the positive edge of the pulse and there is no effect of the falling edge of the light. In most cases the high resistance state (HRS) to low resistance state (LRS) transition is irreversible i.e.the devices continue to remain in the LRS even after the light pulse is switched off. Light induced reset (LIR) is achieved in only one device structure Al/CuxO/Au. By using LIS and LIR, set and reset power of the device can be reduced to a great extent and the set and reset parameters variation also reduces. The current work, thus, points to the possibility of formation and compliance-free resistive random access memory devices.

We show that a group that is hyperbolic relative to strongly shortcut groups is itself strongly shortcut, thus obtaining new examples of strongly shortcut groups. The proof relies on a result of independent interest: we show that every relatively hyperbolic group acts properly and cocompactly on a graph in which the parabolic subgroups act properly and cocompactly on convex subgraphs., Comment: 14 pages, 6 figures

This report deals with the design of handover schemes for radio access networks (RAN) in 5G networks, using programmable data plane switches. In 5G networks, the NG-RAN architecture splits the Base Band Unit (BBU) into Central and Distributed Units (CU and DU). This structure has created a mid-haul Network, connecting CUs and DUs. The recent advancements in dataplane programmability can be used to enhance system performance. We show how P4 switches can be used to parse the packets between DU, CU, and Back Haul (Core Network) for potential system improvements. In particular, we consider the scenario of mobile handover. The proposed protocol is called SMARTHO, illustrating a smart handover. Programming Protocol-Independent Packet Processors (P4) is a programming language designed to support specification and programming the forwarding plane behavior of network switches/routers. In SMARTHO, we use P4 Switches to intervene in the handover process for fixed-path mobile users. A resource pre-allocation scheme that reserves resources before the UE reaches a future cell, is proposed. The solution is implemented using a P4-based switch introduced between the CU and the DU. The P4 switch is used to spoof the behavior of User Equipment (UE) and perform the resource allocation in advance. The proposed SMARTHO framework is implemented in the mininet emulation environment and in a reconfigurable hardware environment using NetFPGA-SUME boards. The emulation results show a handover response time improvement of 18% for a tandem of two HOs and 25% for a tandem of three HOs. For testbed implementation, we used NetFPGA-SUME boards as P4 switches. The handover time was measured to be approximately 50~milliseconds in the experiments conducted.

We compute the density of states for the Cauchy distribution for a large class of random operators and show it is analytic in a strip about the real axis.

In this paper we consider Schr\"{o}dinger operators on $M \times \mathbb{Z}^{d_2}$, with $M=\{M_{1}, \ldots, M_{2}\}^{d_1}$ (`quantum wave guides') with a `$\Gamma$-trimmed' random potential, namely a potential which vanishes outside a subset $\Gamma$ which is periodic with respect to a sub lattice. We prove that (under appropriate assumptions) for strong disorder these operators have \emph{pure point spectrum } outside the set $\Sigma_{0}=\sigma(H_{0,\Gamma^{c}})$ where $H_{0,\Gamma^{c}} $ is the free (discrete) Laplacian on the complement $\Gamma^{c} $ of $\Gamma $. We also prove that the operators have some \emph{absolutely continuous spectrum} in an energy region $\mathcal{E}\subset\Sigma_{0}$. Consequently, there is a mobility edge for such models. We also consider the case $-M_{1}=M_{2}=\infty$, i.~e.~ $\Gamma $-trimmed operators on $\mathbb{Z}^{d}=\mathbb{Z}^{d_1}\times\mathbb{Z}^{d_2}$. Again, we prove localisation outside $\Sigma_{0} $ by showing exponential decay of the Green function $G_{E+i\eta}(x,y) $ uniformly in $\eta>0 $. For \emph{all} energies $E\in\mathcal{E}$ we prove that the Green's function $G_{E+i\eta} $ is \emph{not} (uniformly) in $\ell^{1}$ as $\eta$ approaches $0$. This implies that neither the fractional moment method nor multi scale analysis \emph{can} be applied here.

Let $G$ be a torsion-free hyperbolic group and $\alpha$ an automorphism of $G$. We show that there exists a canonical collection of subgroups that are polynomially growing under $\alpha$, and that the mapping torus of $G$ by $\alpha$ is hyperbolic relative to the suspensions of the maximal polynomially growing subgroups under $\alpha$., Comment: 21 pages, 1 figure. v2: Incorporates referee comments

The investigations of the nanostructured-Al (nano-Al) based thermo-oxidative reaction attributes are detailed in this chapter-5. Two products are selected for the thermo-oxidative reaction studies. They are (1) Nano-Al embedded in the PVP matrix (will be termed as fuel) and (2) its physically mixed 1:1 stoichiometric nanocomposite processed with the ultrafine nc-ceria oxidizer (also will be termed as nanoenergetic material (NEM)), respectively. The graphical abstract presented below illustrates an overview of the thermo-oxidative reaction of fuel tracked employing thermogravimetric analysis (TGA) investigation. Similar TGA experimentation of the designed NEMs is carried out to gather scientific information validating, whether or not a desired enhanced attribute is achieved. Also, in coincidence with the TGA oxidation event, a synchronous exothermic energy release event in differential scanning calorimetry (DSC) trace is observed. The above mentioned two products and their thermo-oxidative reaction behavior employing TGA/DTA and TGA/DSC thermal traces are compared and interpreted based on the data available in the literature., Comment: 26 pages, 7 figures, UoH thesis chapter-5

The viability of ultrasonic sonochemistry is investigated in the context of delivering air-stable metallic Al rich-PVP composite. The parameters investigated are; sono-(1) process intensification, (2) crystallization, (3) agglomeration, and (4) fragmentation, respectively. The conventional solvent of n-hexadecane is employed as the sonotrode generated pressure transmitting medium to carry out the above experiments. Two precursors, (1) Poly (vinylpyrrolidone) (PVP) and (2) Aluminum chloride (AlCl3) are chosen to evaluate and demonstrate the viability of the ultrasonic induced processing. Temperature controlled investigations at RT and higher temperature help in achieving; (a) PVP-graphitization, and (b) Al-crystal growth phenomenon, respectively. The current experiments aid in helping to isolate and identify actual mechanistic happenings. The investigation, thus, has a fabrication protocol of shortened processing-duration, native amorphous oxide-free, metal-rich air-stable product that leads to 10 g of composite product for fuel applications., Comment: 47 pagess, 18 figures, UoH thesis chapter