Nanoscale phase separations in as-fabricated thick super duplex stainless steels

Journal of Materials Science - Nanoscale phase separations, and effects of these, were studied for thick super duplex stainless steel products by atom probe tomography and mechanical testing....     

Mapping of landslide susceptibility using the combination of neuro-fuzzy inference system (ANFIS), ant colony (ANFIS-ACOR), and differential evolution (ANFIS-DE) models

Bulletin of Engineering Geology and the Environment - In this research, landslide susceptibility map of the Fahliyan sub-basin was provided employing adaptive neuro-fuzzy inference system (ANFIS)...     

Two-stage robust energy management of a hybrid charging station integrated with the photovoltaic system

The optimal management of charging stations has become a critical issue in recent years. In this paper, the energy management of a hybrid charging station composed of an electrolyzer, fuel cell and hydrogen storage is analyzed that is integrated with a photovoltaic system. As well, the station is connected to the local power market to increase flexibility and it is assumed that the manager of the charging station is an intelligent decision-maker who tries to minimize the cost of vehicle. Due to the existence of uncertainties, generation of photovoltaic, market price and load demand are considered as uncertain parameters and two-stage stochastic programming is applied to model them. To achieve optimal management, a robust optimization approach is proposed for the uncertainty of day-ahead market price where the decision-maker adjusts the conservatism level. The presented method is linear risk-constrained programming that the results for risk-neutral and risk-averse strategies are compared. To validate the accuracy and robustness of the approach, interval-based stochastic programming is also implemented. According to the robust optimization, day-ahead market price uncertainty increases the total expected cost by about 8.9%. In return, the risk of scheduling is reduced significantly with the risk-averse strategy.     

Incorporation of graphene oxide and calcium phosphate in the PCL/PHBV core-shell nanofibers as bone tissue scaffold

Bone tissue scaffolds should have both desired mechanical stability and cell activities including biocompatibility, cell differentiation, and maturation. Also, suitable mineralization is another key factor for these materials. Hence, in current work, in order to achieve a scaffold with desired mechanical and bioactivity properties, core-shell nanofibers based on the polycaprolactone and poly(3-hydroxybutyrate-co-3-hydroxyvalerate) with different concentration of graphene oxide (GO) (0.5, 1, and 1.5 wt%) and calcium phosphate (CP) (1 and 3 wt%) were prepared to utilize as bone scaffold. Microstructure of nanofibers observed by field emission scanning electron microscope (FE-SEM) and results exhibited that the most of nanofibers had 270–500 nm diameter. Attenuated total reflectance Fourier transform infrared spectroscopy and energy dispersive X-ray evaluations verified appearance of GO and CP into the electrospun scaffolds (ES). Transmission electron microscopy analysis endorsed core-shell structure of nanofibers. X-ray diffraction study moreover determination of semicrystalline structure, verified presence of GO and CaPO₄ into the nanofibers. Water contact angle demonstrates that, ES2 and ES3 situated in suitable domain of hydrophilicity. Tensile analysis determined that, ES2, ES3, and ES4 had the highest mechanical properties for use as bone scaffold. Cell viability assessment confirmed biocompatibility of scaffold during 7 days. Alkaline phosphatase and alizarin red staining exhibited maturating and differentiating of osteocytes after 21 days seeding on the scaffolds.     

Feature Extraction in Fractional Fourier Domain for Classification of Passive Sonar Signals

Journal of Signal Processing Systems - The acoustic signals radiated from the marine vessels contain information about their machinery characteristics that can be useful for the detection and...     

Polymer-clay nanocomposite hydrogels for molecular irrigation application

Novel nanocomposite hydrogel pipes on the basis of polyvinyl alcohol and montmorillonite (MMT) clay were prepared via a cyclic freezing–thawing technique and designed for subsurface irrigation in the agricultural sector with extraordinarily reduced water consumption. The results showed that the prepared nanocomposite hydrogel pipes had an exfoliated morphology with improved mechanical and thermal properties. It was shown that the gel contents of nanocomposite hydrogel pipes were increased by increasing the loading level of MMT and, in contrast, the swelling and drying abilities decreased. The water permeation and irrigating performances of the prepared pipes were investigated at the laboratory scale by taking into account the effects of the MMT loading levels in nanocomposite hydrogels and the thickness of pipes. The results indicated a significant decrease in water consumption in nanocomposite hydrogel pipes compared to the pure hydrogel pipe. © 2019 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2020 , 137, 48631.     

Burst‐aware virtual machine migration for improving performance in the cloud

Burst is a common pattern in the user's requirements, which suddenly increases the workload of virtual machines (VMs) and reduces the performance and energy efficiency of cloud computing systems (CCS). Virtualization technology with the ability to migrate VMs attempts to solve this problem. By migration, VMs can be dynamically consolidated to the users' requests. Burst temporarily increases the workload. Ignoring this issue will lead to incorrect decisions regarding the migration of VMs. It increases the number of migrations and Service Level Agreement Violations (SLAVs) due to overload. This may cause waste of resources, increase in energy consumption, and misplaced VMs. Therefore, a burst‐aware method for these issues is proposed in this paper. The method consists of two algorithms: one for determining the migration time and the other for the placement of VMs. We use the PlanetLab real dataset and CloudSim simulator to evaluate the performance of the proposed method. The results confirm the advantages of the method regarding performance compared to benchmark methods.     

Specification and design of embedded hardware-software systems

Embedded-system specification and design consists of describing a system's desired functionality and mapping that functionality for implementation by a set of system components such as processors, ASICs, memories, and buses. This paper discusses the key problems of system specification and design, including specification capture, design exploration, hierarchical modeling, software and hardware synthesis, and cosimulation. The authors highlight existing tools and methods for solving those problems and describe a “specify-explore-refine” methodology for meeting today's embedded-system product development requirements     

The softening of hardware

In the 1940s, when modern computing began, engineers tended to view computers and the programs running on them as unified entities. Now, after decades in which software and hardware developed along separate paths, we seem to have come full circle. The hardware on which our programs run is thanks to embedded systems. These systems force designers to work under incredibly tight constraints. To understand the technologies developed to satisfy these constraints, we must first distinguish the underlying embedded systems elements.     

Highly configurable platforms for embedded computing systems

Platform chips, which are pre-designed chips possessing numerous processors, memories, coprocessors, and field-programmable gates arrays, are becoming increasingly popular. Platforms eliminate the costs and risks associated with creating customized chips, but with the drawbacks of poorer performance and energy consumption. Making platforms highly configurable, so they can be tuned to the particular applications that will execute on those platforms, can help reduce those drawbacks. We discuss the trends leading embedded system designers towards the use of platforms instead of customized chips. We discuss UCR research in designing highly configurable platforms, highlighting some of our work in highly configurable caches, and in hardware/software partitioning.