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The purpose of this paper is to obtain correctly classified routes based on their parameters.

In this paper, a covering rough set (CRS) approach is proposed for route classification in wireless ad hoc networks. In a wireless network, mobile nodes are deployed randomly in a simulation region. This work addresses the problem of route classification.

The network parameters such as bandwidth, delay, packet byte rate and packet loss rate changes due to the frequent mobility of nodes lead to uncertainty in wireless networks. This type of uncertainty can be very well handled using a rough set concept. An ultimate aim of classification is to correctly predict the decision class for each instance in the data.

The traditional classification algorithms, named K-nearest neighbor, J48, general rough set theory, naive Bayes, JRIP and multilayer perceptron, are used in this work for comparison and for the proposed CRS based on route classification approach revealing better accuracy than traditional classification algorithms.

This paper aims to use the Lattice Boltzmann method (LBM) to numerically simulate the natural convection heat transfer of Cu-water nanofluid in an L-shaped enclosure with curved boundaries.

LBM on three different models of curved L-shape cavity using staircase approach is applied to perform a comparative investigation for the effects of curved boundary on fluid flow and heat transfer. The staircase approximation is a straightforward and efficient approach to simulating curved boundaries in LBM.

The effect of curved boundary on natural convection in different parameter ranges of Rayleigh number and nanoparticle volume fraction is investigated. The curved L-shape results are also compared to the rectangular L-shape results that were also achieved in this study. The curved boundary LBM simulation is also validated with existing studies, which shows great accuracy in this study. The results show that the top curved boundary in curved L-shape models causes a notable increase in the Nusselt number values.

Based on existing literature, there is a lack of comparative studies which would specifically examine the effects of curved boundaries on natural convection in closed cavities. Particularly, the application of curved boundaries to an L-shape cavity has not been examined. In this study, curved boundaries are applied to the sharp corners of the bending section in the L-shape and the results of the curved L-shape models are compared to the simple rectangular L-shape model. Hence, a comparative evaluation is performed for the effect of curved boundaries on fluid flow in the L-shape enclosure.

This study aims to deal with the case adaptation problem associated with continuous data by providing a non-zero base solution for knowledge users in solving a given situation.

Firstly, the neighbourhood transformation of the initial case base and the view similarity between the problem and the existing cases will be examined. Multiple cases with perspective similarity or above a predefined threshold will be used as the adaption cases. Secondly, on the decision rule set of the decision space, the deterministic decision model of the corresponding distance between the problem and the set of lower approximate objects under each choice class of the adaptation set is applied to extract the decision rule set of the case condition space. Finally, the solution elements of the problem will be reconstructed using the rule set and the values of the problem's conditional elements.

The findings suggest that the classic knowledge matching approach reveals the user with the most similar knowledge/cases but relatively low satisfaction. This also revealed a non-zero adaptation based on human–computer interaction, which has the difficulties of solid subjectivity and low adaptation efficiency.

In this study the multi-case inductive adaptation of the problem to be solved is carried out by analyzing and extracting the law of the effect of the centralized conditions on the decision-making of the adaptation. The adaption process is more rigorous with less subjective influence better reliability and higher application value. The approach described in this research can directly change the original data set which is more beneficial to enhancing problem-solving accuracy while broadening the application area of the adaptation mechanism.

The examination of the calculation cases confirms the innovation of this study in comparison to the traditional method of matching cases with tacit knowledge extrapolation.

The algorithm models established in this study develop theoretical directions for a multi-case induction adaptation study of tacit knowledge.

This study designs a multi-case induction adaptation scheme by combining NRS and CBR for implicitly knowledgeable exogenous cases. A game-theoretic combinatorial assignment method is applied to calculate the case view and the view similarity based on the threshold screening.

Porous medium has always been introduced as an environment for increasing heat transfer in cooling systems. However, increase in heat transfer and resolving pressure drop in the fluid flow have been focused on by researchers.The purpose of this paper is to study the effects of creating porous micro-channels inside porous macro-blocks to optimize system performance in channels.

To simulate flow field, a developed numerical code that solves Navier–Stokes equations by finite volume method and semi-implicit method for pressure linked equations (SIMPLE) algorithm will be used together with bi-disperse porous medium (BDPM) method. Working fluid is air with Pr = 0.7 in laminar state. Influence of permeability changes by creation of micro-channels containing porous medium in vertical, horizontal and cross-shape patterns will be investigated.

By creating porous micro-channels inside macro-blocks, not only does the heat transfer increase significantly but the pressure also drops remarkably. Increase in performance evaluation criteria (PEC) is more evident in lower Reynolds numbers that can increase the PEC to 75 per cent by creating cross-shape micro-channels. By changing the permeability of micro-channels, PEC will increase by reducing the pressure drop but it has minor changes in Nu.

The current work is applicable to optimizing system performance by decreasing the pressure drop and increasing the heat transfer.

The developed patterns are useful in increasing the system performance including the increase in heat transfer and decrease in pressure drop in systems such as air coolers required in electrical circuits.

Development and optimization of system performance by new patterns using BDPM in comparison to the previous patterns.

The purpose of this paper is to explore agripreneurship development as a strategy for economic growth and development.

Though a few related literature were reviewed, this paper relies heavily on the author’s viewpoint regarding how Nigeria can grow and develop its economy through agripreneurship development.

The present economic challenges that Nigeria is facing are blamed on overdependence on the oil sector, bad governance, corruption, leadership failure, policy inconsistency, overdependence on imported goods and ostensible neglect of the agricultural sector. Also, policymakers, economic analysts and the government have advocated strongly for diversification of the economy. Besides, there is a consensus among scholars, economic analysts and policymakers that “agriculture is the answer.”

This paper addresses specifically one sector of the economy – the agricultural sector. On the other hand, economic crisis needs to be addressed holistically by resolving specific issues that confront different sectors of the economy.

This paper has some insightful policy and practical implications for the Nigerian Government and Nigerians. The government and Nigerians need to take practical steps to grow and develop the economy. On the part of the government, apart from the need to transform the agricultural sector by allocating enough funds to it, the government should establish well-equipped agripreneurship development centers and organize periodically agripreneurship development programmes for the main purpose of training and developing both current and potential agripreneurs who will be able to apply today’s agricultural techniques and practices which involve a great deal of creativity and innovation for a successful agribusiness. The federal government should integrate agripreneurship education into Nigeria’s education system. Similarly, the Nigerian people, particularly the youths or graduates should be encouraged to choose agribusiness as a career.

While previous papers have offered different solutions to the current economic crisis that Nigeria is experiencing, ranging from economic to structural reforms, this paper differs significantly from others by recommending specifically agripreneurship development as a strategy for revamping Nigeria’s economy from its current recession. Moreover, there is a dearth of literature on agripreneurship and agripreneurship development. This paper therefore fills the literature gap.

To modify a conventional evacuated tube, an improved asymmetric U-type evacuated tube (AUET) is proposed. This study aims to investigate the thermal and hydrodynamic performances of a modified tube and determine the optimal structural form.

Based on the variation of fluid proprieties with temperature, the formulated numerical model was validated and then deployed to investigate the natural circulation in the evacuated tubes. A dimensionless number was proposed to quantify the stratification effect. The influence of the degree of asymmetry of U-type evacuated tubes on the flow patterns, mass flow rate, temperature distribution, thermal stratification and energy conversion efficiency was studied.

When the degree of asymmetry is large, a higher velocity and better thermal stratification are achieved, thereby avoiding stagnant water at the bottom of the tubes simultaneously. Compared with the conventional evacuated tube, the improved evacuated tube exhibited a higher thermal efficiency.

The originally proposed AUET was proven to have better performance in avoiding stagnant water, reducing fluid mixing and improving the heat transfer efficiency.

The purpose of this paper is to examine the influence of magnetic field on Williamson nanofluid embedded in a porous medium in the presence of non-uniform heat source/sink, chemical reaction and thermal radiation effects.

The governing physical problem is presented using the traditional Navier–Stokes theory. Consequential system of equations is transformed into a set of non-linear ordinary differential equations by means of scaling group of transformation, which are solved using the Runge–Kutta–Fehlberg method.

The working fluid is examined for several sundry parameters graphically and in a tabular form. It is noticed that with an increase in Eckert number, there is an increase in velocity and temperature along with a decrease in shear stress and heat transfer rate.

A good agreement of the present results has been observed by comparing with the existing literature results.

Wheat plants were grown in field plots of 3×3m area. After growth period of two months, the growing plants were sprayed with dimethoate and pirimicarb at the recommended dose. Spraying was repeated after a further 45 days. Plant samples were taken at intervals of zero, three, six, nine, 12 and 15 days after each application. A gradual and continuous degradation of the applied pesticides had taken place in the treated wheat shoots up to the end of the experiment. However, dimethoate showed more residues and persistence rather than pirimicarb. The break down and metabolism of the applied pesticides was correlated with some biochemical changes in the sprayed plants. Sampling dates of three and six days after application were the most critical periods to affect plant metabolism. A decline was noticed in chlorophyll, sugars and carbohydrates, total proteins and RNA content of wheat shoots as a function of the applied pesticides. Free amino acids were accumulated in the sprayed plants, meanwhile the DNA content did not show observable changes as a consequence of the applied pesticides treatment.

The central idea of this research article is to examine the characteristics of Clairaut submersions from Lorentzian trans-Sasakian manifolds of type (α, β) and also, to enhance this geometrical analysis with some specific cases, namely Clairaut submersion from Lorentzian α-Sasakian manifold, Lorentzian β-Kenmotsu manifold and Lorentzian cosymplectic manifold. Furthermore, the authors discuss some results about Clairaut Lagrangian submersions whose total space is a Lorentzian trans-Sasakian manifolds of type (α, β). Finally, the authors furnished some examples based on this study.

This research discourse based on classifications of submersion, mainly Clairaut submersions, whose total manifolds is Lorentzian trans-Sasakian manifolds and its all classes like Lorentzian Sasakian, Lorenztian Kenmotsu and Lorentzian cosymplectic manifolds. In addition, the authors have explored some axioms of Clairaut Lorentzian submersions and illustrates our findings with some non-trivial examples.

The major finding of this study is to exhibit a necessary and sufficient condition for a submersions to be a Clairaut submersions and also find a condition for Clairaut Lagrangian submersions from Lorentzian trans-Sasakian manifolds.

The results and examples of the present manuscript are original. In addition, more general results with fair value and supportive examples are provided.

Spain has one of the greatest photovoltaic potentials in Europe. The boom suffered in the photovoltaic sector during the years 2007 and 2008 led to instability in the electrical system, prompting the legislator to develop a large number of legislative changes trying to control the electric system tariff deficit. These measures profoundly affected plant owners creating a non-transparent secondary market, which are not covered by the current exchange platforms. The purpose of this paper is to analyze the current situation of the photovoltaic market in Spain, try to understand it based on its historical sequence and propose efficiency improvement measures, based on the implementation of best practices and market mechanisms.

This paper studies the legislative evolution in the photovoltaic sector in Spain and its effect on owners and investors. The authors propose an intermediation system that improves the efficiency of the secondary market.

The authors propose an intermediation system that improves the efficiency of the secondary market.

The authors have not found any other paper that proposes the creation of a market for photovoltaic facilities to increase efficiency.