Fixed point results of F-rational cyclic contractive mappings on 0-complete partial metric spaces

© 2018 Forum-Editrice Universitaria Udinese SRL. All rights reserved. Wardowski [19] introduced a new concept of contraction which called F-contraction and proved a fixed point theorem on complete metric space. Following this direction of research, in this paper, we introduce an F-rational cyclic contraction on partial metric spaces and we present new fixed point results for such cyclic contraction in 0-complete partial metric spaces. An example is given to illustrate the main result, also an application to integral equation is given to show the usability of our results

Proficiency level and language learning strategies among Jordanian students at Universiti Utara Malaysia

This study examines the relationship between proficiency level and language learning strategies (LLSs) among Jordanian students enrolled at Universiti Utara Malaysia. The frequency level of the LLSs employed by the students was also investigated.The theoretical foundation for the study was provided by three comprehensive theories which are the Behaviorism, the Cognitive Psychology, and the Schema Theory.The data for the LLSs was obtained from using Oxford’s (1990) Strategy Inventory for Language Learning (SILL) that classifies six different strategies: 1) Memory Strategy (MS), (2) Cognitive Strategy (COG), (3)Compensation Strategy (COMPS), (4) Metacognitive Strategies (MET), (5) Affective Strategy (AFCS) and (6)Social Strategies (SOC). The frequency of the students’ overall use of LLSs was determined on a five-point Likert scale, ranging from high frequency use (3.5-5.0), medium frequency use (2.5-3.49), to low frequency use (1.0-2.49). Questionnaires were distributed and collected from a total of 97 students. Meanwhile, the students’ level of language proficiency was determined by their scores in the UUM English Language Proficiency Test (ELPT). Upon using the multiple regression analysis, the results show that the students used language learning strategies at a high frequency level.In addition, this study shows that there is a positive relationship between language learning strategy and proficiency level.These results indicate that proficiency level plays a vital role in determining the kinds of language learning strategy used.Curriculum designers and related bodies in Jordan should increase focus on the role of language learning strategies in promoting the acquisition of English language proficiency. The study also opens up avenues for more studies on language learning strategies not only in Jordan, but also in other countries where this area of study is lacking

A best proximity point theorem for special generalized proximal ?-quasi contractive mappings

In this paper, we obtain some best proximity point results for a new class of non-self mappings T: A? B called special generalized proximal ?-quasi contractive. Our result is illustrated by an example. Several consequences are derived. - 2019, The Author(s).Scopu

Generalization of best proximity points theorem for non-self proximal contractions of first kind

The primary objective of this paper is the study of the generalization of some results given by Basha (Numer. Funct. Anal. Optim. 31:569-576, 2010). We present a new theorem on the existence and uniqueness of best proximity points for proximal ?-quasi-contractive mappings for non-self-mappings S: M? N and T: N? M. Furthermore, as a consequence, we give a new result on the existence and uniqueness of a common fixed point of two self mappings. - 2019, The Author(s).Scopu

The Significance of Wind Turbines Layout Optimization on the Predicted Farm Energy Yield

Securing energy supply and diversifying the energy sources is one of the main goals of energy strategy for most countries. Due to climate change, wind energy is becoming increasingly important as a method of CO2-free energy generation. In this paper, a wind farm with five turbines located in Jerash, a city in northern Jordan, has been designed and analyzed. Optimization of wind farms is an important factor in the design stage to minimize the cost of wind energy to become more competitive and economically attractive. The analyses have been carried out using the WindFarm software to examine the significance of wind turbines’ layouts (M, straight and arch shapes) and spacing on the final energy yield. In this research, arranging the turbines facing the main wind direction with five times rotor diameter distance between each turbine has been simulated, and has resulted in 22.75, 22.87 and 21.997 GWh/year for the M shape, Straight line and Arch shape, respectively. Whereas, reducing the distance between turbines to 2.5 times of the rotor diameter (D) resulted in a reduction of the wind farm energy yield to 22.68, 21.498 and 21.5463 GWh/year for the M shape, Straight line and Arch shape, respectively. The energetic efficiency gain for the optimized wind turbines compared to the modeled layouts regarding the distances between the wind turbines. The energetic efficiency gain has been in the range between 8.9% for 5D (rotor diameter) straight layout to 15.9% for 2.5D straight layout

C-class functions with new approach on coincidence point results for generalized (ψ,φ)-weakly contractions in ordered b-metric spaces

In this paper, by using the C-class functions and a new approach we present some coincidence point results for four mappings satisfying generalized (ψ,φ) -weakly contractive condition in the setting of ordered b-metric spaces. Also, an application and example are given to support our results.Scopu

Extended rectangular b-metric spaces and some fixed point theorems for contractive mappings

In this paper, we introduce the class of extended rectangular b-metric spaces as a generalization of both rectangular metric and rectangular b-metric spaces. In addition, some fixed point results connected with certain contractions are obtained and examples are given to illustrate these results.Scopu

Fixed point results using Ft-contractions in ordered metric spaces having t-property

In this paper, we prove the existence of fixed points of Ft-contraction mappings in partially ordered metric spaces not necessarily complete. We require that the ordered metric space has the t-property, which is a new concept introduced recently by Rashid et.al. We also give some examples to illustrate the new concepts and obtained results.The publication of this article was funded by the Qatar National Library

Ordered Sp -metric spaces and some fixed point theorems for contractive mappings with application to periodic boundary value problems

In this paper, we introduce the structure of Sp-metric spaces as a generalization of both S-metric and Sb-metric spaces. Also, we present the notions of S?-contractive mappings in the setup of ordered Sp-metric spaces and investigate the existence of a fixed point for such mappings under various contractive conditions. We provide examples to illustrate the results presented herein. An application to periodic boundary value problems is presented. - 2019, The Author(s).The publication of this article funded by the Qatar National Library.Scopu

Potential Study of Solar Thermal Cooling in Sub-Mediterranean Climate

Air conditioning is becoming increasingly important in the energy supply of buildings worldwide. There has been a dramatic increase in energy requirements for cooling buildings in the Middle East and North Africa (MENA) region. This is before taking the effects of climate change into account, which will also entail a sharp increase in cooling requirements. This paper presents the potential of using a solar thermal absorption cooling system in Sub-Mediterranean Climate. Four sites in Jordan are now equipped with water-lithium bromide (H2O-LiBr) absorption chillers with a total nominal capacity of 530 kW. The focus of the paper was on the pilot system at the German Jordanian University (GJU) campus with a cooling capacity of 160 kW. The system was designed and integrated in order to support two existing conventional compression chillers with a nominal cooling capacity of 700 kW. The system was economically evaluated based on the observed cooling capacity results with a Coefficient of Performance (COP) equals 0.32, and compared with the values observed for a COP of 0.79 which is claimed by the manufacturer. Several techniques were implemented to evaluate the overall economic viability in-depth such as present worth value, internal rate of return, payback period, and levelized cost of electricity. The aforementioned economic studies showed that the absorption cooling system is deemed not feasible for the observed COP of 0.32 over a lifespan of 25 years. The net present value was equal to −137,684 JD and a payback period of 44 years which exceeds the expected lifespan of the project. Even for an optimal operation of COP = 0.79, the discounted payback period was equal to 23 years and the Levelized Cost of Electricity (LCOE) was equal to 0.65 JD/kWh. The survey shows that there are several weaknesses for applying solar thermal cooling in developing countries such as the high cost of these systems and, more significantly, the lack of experience for such systems.DFG, 414044773, Open Access Publizieren 2019 - 2020 / Technische Universität Berli