Positive Definite Tensors to Nonlinear Complementarity Problems

The main purpose of this note is to investigate some kinds of nonlinear complementarity problems (NCP). For the structured tensors, such as, symmetric positive definite tensors and copositive tensors, we derive the existence theorems on a solution of these kinds of nonlinear complementarity problems. We prove that a unique solution of the NCP exists under the condition of diagonalizable tensors.Comment: 11 page

A modified modulation scheme for three-level diode-clamped matrix converter under unbalanced input conditions

The three-level diode-clamped matrix converter topology has outstanding performance under ideal operating conditions. However, input disturbance can influence the waveforms at the output side of the converter due to the direct coupling between the input and output. This paper proposes a modified modulation scheme for three-level diode-clamped matrix converter during operation with unbalanced input voltages and when different transformer turns ratios are used for an isolation transformer at the input. With this modulation technique, sinusoidal and balanced output voltages are guaranteed and the input current harmonics are minimized. Experimental results are presented to demonstrate the feasibility and effectiveness of the proposed modulation scheme

A catalyst-controlled selective synthesis of pyridines and pyrroles

We have developed a dual reaction manifold that enables selective synthesis of both pyridines and pyrroles from common substrates ??-diazo oxime ethers. The strong propensity of 1,3-dienyl nitrenes for 4??-electrocyclization to give pyrroles could be diverted to 6??-electrocyclization via 1,6-hydride shift or prototropic isomerization leading to exclusive formation of pyridines by employing metal nitrene complexes derived from ??-diazo oxime ethers under Rh(II) catalysis. Furthermore, an orthogonal catalytic system has been identified that promotes selective formation of 1H-pyrroles from the same substrates by redirecting the reactivity of vinyl 2H-azirine intermediates.close3

Superconducting properties and c-axis superstructure of Mg1-xAlxB2

The superconducting and structural properties of a series of Mg1-xAlxB2 samples have been investigated. X-ray diffraction results confirmed the existence of a structural transition associated with the significant change in inter-boron layer distance as reported previously by Slusky et al. Moreover,transmission-electron-microscopy observations revealed the existence of a superstructure with doubled lattice constant along the c-axis direction. We propose that this superstructure is essentially related to the structural transition. The modifications of superconducting transition temperature Tc, the normal state resistivity, and the upper critical field Bc2 by Al doping are discussed in terms of Al-substitution induced changes in the electronic structure at the Fermi energy.Comment: 15 pages, 7 figure

BlueSWAT: A Lightweight State-Aware Security Framework for Bluetooth Low Energy

Bluetooth Low Energy (BLE) is a short-range wireless communication technology for resource-constrained IoT devices. Unfortunately, BLE is vulnerable to session-based attacks, where previous packets construct exploitable conditions for subsequent packets to compromise connections. Defending against session-based attacks is challenging because each step in the attack sequence is legitimate when inspected individually. In this paper, we present BlueSWAT, a lightweight state-aware security framework for protecting BLE devices. To perform inspection on the session level rather than individual packets, BlueSWAT leverages a finite state machine (FSM) to monitor sequential actions of connections at runtime. Patterns of session-based attacks are modeled as malicious transition paths in the FSM. To overcome the heterogeneous IoT environment, we develop a lightweight eBPF framework to facilitate universal patch distribution across different BLE architectures and stacks, without requiring device reboot. We implement BlueSWAT on 5 real-world devices with different chips and stacks to demonstrate its cross-device adaptability. On our dataset with 101 real-world BLE vulnerabilities, BlueSWAT can mitigate 76.1% of session-based attacks, outperforming other defense frameworks. In our end-to-end application evaluation, BlueSWAT patches introduce an average of 0.073% memory overhead and negligible latency