Hybrid intelligent framework for one-day ahead wind speed forecasting

Neural Computing and Applications - Nowadays wind power is considered as one of the fastest growing alternative energies, that is expected to continue to grow rapidly in the upcoming...     

Performance analysis of a solar-assisted swimming pool heating system

This paper deals with feasibility studies for a solar-assisted heating system for the University of Miami's Aquatic Center using the simulation program TRNSYS. The Aquatic Center is composed of an outdoor olympic size swimming pool and locker room building. The solar heating is accomplished by employing hot water generated by heat exchange with the solar collector working fluid. Two thermal storage tanks are employed for the collector and domestic use. The performance of the system is analyzed from both thermodynamic and economic standpoints and general conclusions are reached.     

On business process monitoring using cross-flow coordination

This paper presents an approach for monitoring the execution progress of business processes. The monitoring focuses on the exceptions that could arise during this execution and, hence, could make the processes fail if not handled properly and timely. The approach relies on three flows known as control, communication, and navigation. The control flow connects tasks together with respect to a certain business logic. The communication flow captures the messages exchanged between persons/machines when they perform tasks of processes. Finally, the navigation flow captures the interactions between specialized networks that offer solutions to exceptions. These networks are built upon relations between tasks, between persons, and between machines. The coordination of control, communication, and navigation flows focuses on both the actions that are taken and the messages that are exchanged when handling exceptions. A system demonstrating flow development and coordination is, also, presented in the paper.     

Zebra mussels and Eurasian watermilfoil reporting patterns in Minnesota

Recognizing common reporting patterns of aquatic invasive Zebra mussels (Dreissena polymorpha, ZM) and Eurasian watermilfoil (Myriophyllum spicatum, EWM) helps to better understand invasions. We hypothesize that confirmed invasions may be confounded by human population density, leading to overrepresentation of invasions in highly populated areas and underrepresentation in less populated areas. Here we recognize dispersal patterns of confirmed ZM and EWM invasions in Minnesota, USA, using spatial clustering and directionality tests, while adjusting for human density. By 2015, 125 (0.68%) and 304 (1.65%) of 18,411 Minnesota waterbodies were reported to have ZM and EWM, respectively. A multivariate multinomial model of the scan test was used to identify clustering of invasions. The resulting 23 clusters included 13 with either or both ZM and EWM, and most clusters (11/13) occurred in areas with >10 people per square kilometer. Whereas, among the 10 clusters without invasion, nine were from less populated areas. The standard deviation ellipse and the spatiotemporal directionality tests indicated a northwestern trend of invasions, which is in the same direction as the I-94 interstate highway connecting urban centers. Results suggested that confirmed ZM and EWM invasions are potentially confounded by human densities, which is explained by varying human impact on either or both dispersal and reporting of invasions. Considering this impact of human density, we suggest that a combination of passive and targeted surveillance, where the magnitude of efforts are stratified by the human densities, may provide insight into the true invasion status and its progression in the Great Lakes region.     

Magnetocaloric effect of polycrystalline La0.5Sm0.2Sr0.3Mn1-xCrxO3 (0 ≤ x ≤ 0.20) compound prepared by glycine-nitrate process

Journal of Materials Science: Materials in Electronics - This paper reports the effect of chromium’s substitution in magnetic oxides with perovskite structure La0.5Sm0.2Sr0.3Mn1-xCrxO3...     

An experimental study for a combined system of tar sand, oil shale, and olive cake as a potential energy source in Jordan

Jordan is an example of a third world country that is non-oil producing but contains huge reserves of other energy sources such as tar sand, oil shale, and olive cake. Some limited research is available about how to utilize these energy sources in pure form. However, available research does not deal with combinations of these energy sources. This experimental study investigates combinations of these energy forms as potential energy sources in Jordan. The experimental procedure involves characterization of samples by proximate analysis, calorific value determination of different combinations, and a compacting process of the different particles. The best combination, with respect to calorific value, is found to be 20% tar sand, 20% olive cake, and 60% oil shale. Compacting materials either with starch or with heated tar sand up to 110°C for 1 h indicates a feasible process for handling, packaging, and transporting.     

Feasibility study of a solar-assisted heating/cooling system for an aquatic centre in hot and humid climates

This paper reports on a feasibility study of a solar-powered heating/cooling system for a swimming pool/space combination in a tropical environment. The system utilizes an absorption chiller and a cooling tower to meet the facilities and locker room load. The heating is accomplished by employing hot water generated by heat exchange with the solar collector working fluid. Two thermal storage tanks were employed for the collector and domestic use. The absorption chiller utilizes hot water to regenerate the LiBr solution. The proposed system enables the swimming season to be extended from sixteen weeks to fifty-two weeks. Simulation results indicate that a combination of a double glazed collector area of 600–4800 m² and a storage tank volume of 11·36 m³ results in a 25–37% reduction in the consumption of natural gas. Economic analysis is performed based on the life-cycle-cost method and takes into account the effects of discount rate, fuel price and fuel inflation rate. Different scenarios for which the solar-assisted system is economical are presented and analysed. © 1997 John Wiley & Sons, Ltd.     

Advanced modeling and control of wind conversion systems based on hybrid generators using fractional order controllers

The focus of this study is on modeling and management of a Wind Energy Conversion System (WECS) based on a Hybrid Excitation Synchronous Generator (HESG). Using a wind simulator, two controllers, CRONE and H_∞, are evaluated for Maximum Power Point Tracking (MPPT) and optimal rotation speed. The results show the CRONE controller's higher tracking capability, and robustness tests investigate the influence of parametric uncertainty. Space harmonic effects, commutation effects, and turbine shaft flexibility are all addressed in the sophisticated models. The introduction of Fractional Order Proportional-Integral (FOPI) control for MPPT is a game changer. Although fractional calculus-based accuracy and robustness are uncommon in WECS, they show promise for emissions reduction and increased energy efficiency. This work validates a dependable control approach inside an isolated HESG-based WECS's power-maximizing range. Extensive investigation of the parameters impacting FOPI control efficiency yields useful insights for effective MPPT control. A variable-speed wind turbine (WT) is linked to a HESG through a multiplier, with a controller controlling generator coil excitation voltages and a rectifier connecting the WECS to a load. A thorough 3 kW HESG electrical model that includes generator space harmonics and converter commutation effects is among the contributions. For HESG-based WECS stability, frequency analysis finds important resonant and anti-resonant frequencies. These issues are addressed by a FOPI control technique, which ensures system stability and performance. The necessity of exact frequency analysis in HESG-based WECS is highlighted by a step-by-step controller parameter tuning approach.     

Properties of Coated Controlled Release Diammonium Phosphate Fertilizers Prepared with the Use of Bio-based Amino Oil

In an effort to enhance the efficiency of fertilizer use and minimize their negative impact on the environment, a novel biomass-based, functional controlled-release fertilizer was used to improve nutrient use efficiency and increase crop production systems for more sustainable agriculture practices. Here, bio-based amino-oil (Priamine) mixtures were proposed as an outer coating with different layers for the control of phosphorus release from diammonium Phosphate (DAP). These hydrophobic coatings conferred excellent barrier properties and flexibility to coatings. The morphological characterization of the coated fertilizer was performed by scanning electronic microscopy (SEM), electronic diffraction X-ray (EDX) and mapping, and revealed the formation of a cohesive film and a good adhesion between DAP fertilizer and coating film. The release rate of nutrients (phosphate) in water was investigated by UV–Vis spectrophotometer. The effect of coating thickness was investigated on release time and diffusion coefficient of phosphor release in distilled water. Release time increased with the coating thickness. The diffusion coefficient of nutrient release decreased with the coating thickness. Compared with uncoated granule which is totally solubilized after less than 2 hours, the P release profiles of the coated granules reached the equilibrium stage approximately after 98 and 126 hours when the DAP is coated with only Priamine single-layer (1L) and double-layer (2L), respectively. Moreover, the strategy adopted has successfully provided a very slow release and long-term availability of nutrient sources with bio-based coating oil compared to uncoated fertilizer (DAP) and therefore exhibited promising application for sustainable development of modern agriculture and circular economic.     

Decentralized collaborative business process execution using blockchain

World Wide Web - Blockchain technology enables several untrustworthy parties to execute inter-organizational business processes in a tamper-proof manner. Existing approaches are based on smart...