LDES: detector design for version number attack detection using linear temporal logic based on discrete event system

International Journal of Information Security - The Internet Engineering Task Force (IETF) has defined routing protocols for low power and lossy networks (RPL) for constrained devices. RPL...     

Run-time issues in program partitioning on distributed memory systems

Our earlier work reported a Threshold Scheduling Method for compile-time mapping of functional parallism on distributed-memory systems. The work reported in this paper discusses run-time issues in efficiently supporting the functional parallism with minimal overheads, through a combination of compile-time and run-time ownership analysis. At compile time, the code generation phase determines whether a local copy of a live definition of a variable needed by a task is available on a given processor, through an ownership analysis. In case ownership cannot be resolved at compile time, an appropriate code is generated to perform analysis at run time. The code generation is carried out so that all the processors carry the same copy of the compiled program with the individual processor's code being isolated and the universally owned code being replicated on all processors to minimize run-time overheads. The run-time system maintains the static and dynamic ownerships at every processor to avoid communication overhead on ownership information. We demonstrate the approach by incorporating it in the compiler for targeting a parallel functional language, Sisal (streams and iterations in single assignment language), to Intel Touchstone i860 systems. Several benchmarks demonstrate the viability of the approach.     

Asymmetric Aerobic Oxidation of α‐Hydroxy Acid Derivatives Catalyzed by Reusable,Polystyrene‐Supported Chiral N‐Salicylidene Oxidovanadium tert‐Leucinates

The direct immobilization of two different C‐5‐propargyl ether‐modified, chiral N‐salicylidene vanadyl(V) tert‐leucinates onto 4‐azidomethyl‐substituted polystyrene by click chemistry was examined. Among the eight different solvents investigated, the resulting polystyrene‐supported catalysts promote the asymmetric, aerobic oxidation of α‐hydroxy (thio)esters and amides with enantioselectivities of up to 99% ee (selectivity factor up to 41) in chloroform. These polystyrene‐supported catalysts can be readily recovered by filtration and reused for at least four consecutive runs without discernible loss of reactivity and enantioselectivity.     

Gradient Microstructure and Properties of Surface Mechanical Attrition–Treated AZ91D Alloy: An Effect of Colliding Balls Velocity

The surface properties of the AZ91D alloy are altered using surface mechanical attrition treatment (SMAT), a promising method of severe surface deformation, where the role of process parameters is crucial. In this study, specimens are SMATed using ≈3 and ≈10 m s⁻¹ ball velocities (maintaining a constant percentage coverage). The SMATed specimens show higher twin density near the surface, which is reduced gradually, and twin thickness is increased with increasing depth. Further, high-velocity balls cause more twin density and better grain refinement (≈32 nm grain size at the surface). The higher ball velocity helps form a considerably thicker gradient layer (≈3500 μm) with higher hardness (≈1.98 GPa) and compressive residual stress (≈281 MPa) within a shorter SMAT duration (≈10 min). Ball velocity also influences nanomechanical properties such as nanohardness, creep resistance, strain rate sensitivity (SRS), etc. The non-SMATed alloy's SRS is about 0.037–0.040. The gradient microstructure affects SRS. The SRS value near the SMATed surface (where the reduced grain size plays a dominating role) is about 0.018–0.027; however, it drops suddenly to ≈0.01 (with a slight increase in depth), and subsequently, it rises with an increased distance in the SMATed layer (where twins play a dominating role).     

Photovoltaics literature survey (no. 78)

In order to help keep readers up‐to‐date in the field each issue of Progress in Photovoltaics will contain a list of recently published journal articles most relevant to its aims and scope. This list is drawn from an extremely wide range of journals, including IEEE Transactions on Electron Devices, Journal of Applied Physics, Applied Physics Letters, Progress in Photovoltaics and Solar Energy Materials and Solar Cells. To assist the reader, the list is separated into broad categories, but please note that these classifications are by no means strict. Also note that inclusion in the list is not an endorsement of a paper's quality. If you have any suggestions please email Santosh Shrestha at mailto: s.shrestha@unsw.edu.au .

     

Effects of hBN and Y2O3 Addition on Mechanical and Tribological Behavior of SiC Ceramic Matrix Composites Prepared by Spark Plasma Sintering

Silicon - The objective of the present work is to study the mechanical and tribological properties of SiC-hBN such as hardness, density, fracture toughness, friction and wear behavior with and...     

A SiGe-Source Doping-Less Double-Gate Tunnel FET: Design and Analysis Based on Charge Plasma Technique with Enhanced Performance

Silicon - In this article, a distinctive charge plasma (CP) technique is employed to design two doping-less dual gate tunnel field effect transistors (DL-DG-TFETs) with Si0.5Ge0.5 and Si as source...     

Machine Learning Assisted Analysis,Prediction, and Fabrication of High-Efficiency CZTSSe Thin Film Solar Cells

The Earth-abundant element-based Cu₂ZnSn(S,Se)₄ (CZTSSe) absorber is considered as a promising material for thin-film solar cells (TFSCs). The current record power conversion efficiency (PCE) of CZTSSe TFSCs is ≈13%, and it's still lower than CdTe and CIGS-based TFSCs. A further breakthrough in its PCE mainly relies on deep insights into the various device fabrication conditions; accordingly, the experimental–oriented machine learning (ML) approach can be an effective way to discover key governing factors in improving PCE. The present work aims to identify the key governing factors throughout the device fabrication processes and apply them to break the saturated PCE for CZTSSe TFSCs. For realization, over 25,000 data points were broadly collected by fabricating more than 1300 CZTSSe TFSC devices and analyzed them using various ML techniques. Through extensive ML analysis, the i-ZnO thickness is found to be the first, while Zn/Sn compositional ratio and sulfo-selenization temperature are other key governing factors under thin or thick i-ZnO thickness to achieve over 11% PCE. Based on these key governing factors, the applied random forest ML prediction model for PCE showed Adj. R² = >0.96. Finally, the best-predicted ML conditions considered for experimental validation showed well-matched experimental outcomes with different ML models.     

Recent Advances in Small Molecule-Based Intracellular pH Probes

Intracellular pH plays an important role in many biological and pathological processes. Small-molecule based pH probes are found to be the most effective for pH sensing because of ease of preparation, high sensitivity, and quick response. They have many advantages such as small perturbation to the functions of the target, functional adaptability, cellular component-specific localization, etc. The present review highlights the flurry of recent activity in the development of such probes. The probes are categorized based on the type of fluorophore used like quinoline, coumarin, BODIPY, rhodamine, indolium, naphthalimide, etc., and their analytical performance is discussed.