Sustainable energy systems: Role of optimization modeling techniques in power generation and supply—A review

Electricity is conceivably the most multipurpose energy carrier in modern global economy, and therefore primarily linked to human and economic development. Energy sector reform is critical to sustainable energy development and includes reviewing and reforming subsidies, establishing credible regulatory frameworks, developing policy environments through regulatory interventions, and creating market-based approaches. Energy security has recently become an important policy driver and privatization of the electricity sector has secured energy supply and provided cheaper energy services in some countries in the short term, but has led to contrary effects elsewhere due to increasing competition, resulting in deferred investments in plant and infrastructure due to longer-term uncertainties. On the other hand global dependence on fossil fuels has led to the release of over 1100 GtCO₂ into the atmosphere since the mid-19th century. Currently, energy-related GHG emissions, mainly from fossil fuel combustion for heat supply, electricity generation and transport, account for around 70% of total emissions including carbon dioxide, methane and some traces of nitrous oxide. This multitude of aspects play a role in societal debate in comparing electricity generating and supply options, such as cost, GHG emissions, radiological and toxicological exposure, occupational health and safety, employment, domestic energy security, and social impressions. Energy systems engineering provides a methodological scientific framework to arrive at realistic integrated solutions to complex energy problems, by adopting a holistic, systems-based approach, especially at decision making and planning stage. Modeling and optimization found widespread applications in the study of physical and chemical systems, production planning and scheduling systems, location and transportation problems, resource allocation in financial systems, and engineering design. This article reviews the literature on power and supply sector developments and analyzes the role of modeling and optimization in this sector as well as the future prospective of optimization modeling as a tool for sustainable energy systems.     

Effect of (Co–TeO2-doped polyvinylpyrrolidone) organic interlayer on the electrophysical characteristics of Al/p-Si (MS) structures

Journal of Materials Science: Materials in Electronics - In this paper, (Co–TeO2) nanostructures were synthesized using the microwave-assisted method for the fabrication of...     

Phaseless near-field to far-field transformation based on source current reconstruction and signal subspace optimization

In this article, an algorithm for the phaseless near-field (NF) to far-field (FF) transformation based on the source current reconstruction method (SRM) is proposed. The algorithm starts with decomposing the equivalent currents of the antenna under test (AUT) into a deterministic and ambiguous current. The deterministic portion of the current is determined from the phaseless signal subspace-based optimization method (SOM), while several iterative forward-backward propagations add the ambiguous portion. It is shown that with the SOM initialization, no further prior information about the antenna under test is needed and the iterative scheme can converge to the desired result within a few iterations. A simulation and a measurement example validate the proposed algorithm. All results show an accurate, fast, and stable phaseless field transformation is obtained.     

Design of Zn1−xCuxO Nanocomposite Ag-Doped as an Efficient Antimicrobial Agent

Journal of Inorganic and Organometallic Polymers and Materials - This study aims at the preparation of antimicrobial nanoparticles hybrid based on silver (Ag) doped Zn1?xCuxO. Zn1?xCuxO...     

Statistical analyses of landslide size and spatial distribution triggered by 1990 Rudbar-Manjil (Mw 7.3) earthquake,northern Iran: revised inventory,and controlling factors

Bulletin of Engineering Geology and the Environment - This study is a revised inventory of landslides triggered by the Rudbar-Manjil earthquake (Mw = 7.3), 1990, obtained through the...     

Information-Based Node Selection for Joint PCA and Compressive Sensing-Based Data Aggregation

Wireless Personal Communications - Recently it has been shown that when Principal Component Analysis is applied as a dictionary learning technique to Compressive Sensing-based data aggregation,...     

Retraction Note to: Modeling hardness of Nb-microalloyed steels using fuzzy logic

Neural Computing and Applications - The Editor-in-Chief has retracted this article [1] because it significantly overlaps with a number of articles including those that were under consideration at...     

Optimal image compression via block-based adaptive colour reduction with minimal contour effect

Current image acquisition devices require tremendous amounts of storage for saving the data returned. This paper overcomes the latter drawback through proposing a colour reduction technique which first subdivides the image into patches, and then makes use of fuzzy c-means and fuzzy-logic-based inference systems, in order to cluster and reduce the number of the unique colours present in each patch, iteratively. The colours available in each patch are quantised, and the emergence of false edges is checked for, by means of the Sobel edge detection algorithm, so as to minimise the contour effect. At the compression stage, a methodology taking advantage of block-based singular value decomposition and wavelet difference reduction is adopted. Considering 35000 sample images from various databases, the proposed method outperforms centre cut, moment-preserving threshold, inter-colour correlation, generic K-means and quantisation by dimensionality reduction.

     

Encapsulation and delivery of bioactive compounds using spray and freeze-drying techniques: A review

Abstract

There are various bioactive components exist in plants, fruits, and vegetable origins that have many beneficial health effects (mainly antioxidant). However, they suffer from low-stability against the environmental condition. Thus, the encapsulation approach emerged to decrease their sensitivity and present a target delivery system. Generally, native carrier agents (polysaccharides and proteins) are being applied to embed the core materials. Accordingly, many encapsulation methods have been developed to protect vulnerable components by these carriers. Spray and freeze-drying are common encapsulation methods with the ability of powder production. Both feed emulsion production and drying process factors substantially influence the core embedded within the carrier agents. Spray-drying is well-known to higher applicable and scalable encapsulation procedure in the food and pharmaceutical industries. It is predominantly related to its lower process costs. Nevertheless, its application is limited for more sensitive bioactive compounds due to hot-air drying exertion. In contrast, freeze-drying has been mostly used for thermo-sensitive ingredients. Its application is restricted by economic drawbacks for which long process time (24–48?h) is required. However, freeze-drying is adequately taken into an advantage in the encapsulation of therapeutic compounds since high-added value products will be produced so that bioactive compounds with higher biological activity are needed.