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This study adopted a review of bond strength and discussed the research in geopolymer concrete. Studies and research on the structural properties of geopolymer concrete are relatively limited in comparison to ordinary concrete. As a result, this review covers the majority of the research on the Bond Strength of geopolymer concrete, cementitious materials and curing regimes. Many investigations on several researchers have worked on geopolymer concrete. Geopolymer Concrete has the advantage of using extra cementitious materials in conjunction with alkali-activated solutions to substitute cement (The reaction of geopolymer concrete materials is activates by it). After doing a study on previous researches, the output of reviewed papers explained that the pozzolanic materials and curing conditions are affected in the clear for the bond strength; it has been discovered that geopolymeric concrete made from fly ash performs better than Conventional Concrete based on Portland cement in terms of mechanical properties, withstanding high temperature, and preservation of fundamental physical characteristics including permeability and water absorption. Whereas few studies exanimated the effect of fiber on bond strength. [ABSTRACT FROM AUTHOR]

Advanced approaches of antenna arrays like the smart antenna SA and the multiple-input multiple-output massive MIMO schemes have provided an increasing improvement to 5G telecommunication networks. Due to the advantages of that, SAS can be produced by enhancing the response with regard to omnidirectional antennas. In recent researches, several techniques have been used to control the weights of the elements of the smart antenna, however, the optimum scheme do not employ the full requirements for wireless networks, therefore, they do not provide the optimum performance in which SAs for massive MIMO schemes. In this paper, a new idea has been proposed to obtain enhancement to smart antennas for MIMO 5G communication networks. The idea is based on using the affine projection sign algorithm (APSA) in multi-element smart antenna scheme. Special software is developed to integrate the parameters of the smart antenna alongside with the adaptive algorithm. This approach combines the advantages of various smart antennas types. The new smart antenna scheme is designed and simulated for MIMO environment. A comparison is made with well-known literature SA algorithms. The results showed a noticeable improvement in the mean square error (MSE) convergence, pattern recognition as well as the overall antenna gain and sensitivity, as compared to other existing literature techniques. The developed smart MIMO antenna model resonates at 2.67 GHz with a percentage bandwidth of approximately 20%. The gain and bandwidth measurements have shown a superior performance of the developed smart MIMO antenna, which makes it suitable for 5G mobile devices and services. [ABSTRACT FROM AUTHOR]

Methylene blue (MB) is one of the synthetic dyes found in textile industry waste. Several methods ever used to overcome MB problems such as adsorption, filtration, and precipitation can only change MB from one phase to another, causing secondary pollutants. In this research, a Fenton-like composite catalyst, one of the advanced oxidation process (AOP) methods has been synthesized to solve MB waste. The composite catalyst was synthesized by combining zeolite-NaY in Fe3O4 precursor by coprecipitation method in two different solvents (H2O and HCl). The composite catalyst was characterized by XRD, FTIR, and SEM. The combination of Fe3O4 and zeolite-NaY can be seen from the X-Ray diffraction. FTIR analysis proved the success of the synthesis by showing the presence of new vibration at 581 cm−1 indicating the Fe-O bond in the composite catalyst. The performance of the composite catalyst was then tested by degrading 100 mL MB 10 ppm through the Fenton reaction with the addition of hydrogen peroxide as an oxidizing agent. The results showed that more than 90% of MB could be degraded within 10 minutes using the synthesized composite catalyst with HCl solvent (FeZ-A). The lower degradation percentage was shown by the catalyst synthesized with water solvent (FeZ), which was 45%. [ABSTRACT FROM AUTHOR]

At high temperatures, asphalt pavement structures are more prone to permanent deformation. The purpose of this study is to determine the influence of wax-based surfactant (WS) on the behaviour of asphalt binders modified with cup lump rubber (CLR). This study aims to determine the effect of WS on the high temperature properties of CLR modified asphalt binder. Based on the weight of the CLR modified asphalt binders, four different percentages of WS were used in this study: 0.1 %, 0.15 %, 0.2 %, and 0.25 %. The penetration value, softening point, elasticity recovery, torsional recovery and ductility of CLR modified asphalt binders with and without WS were analysed. The results indicate that the addition of CLR with WS improved the asphalt binder rutting and heavy loading properties at high temperatures. [ABSTRACT FROM AUTHOR]

This study utilizes the microwave method to determine the optimum conditions for synthesizing carbon quantum dots (CQDs) trough activated carbon from coffee arabica grounds. Response Surface Methodology (RSM) with a Box-Behnken Design was used for optimization (BBD). In this study, a 200-mesh activated carbon obtained from coffee grounds was used as a raw material for synthesizing CQDs using the microwave method. The independent variables that are estimated to influence the measured parameters are the mass of activated carbon (X1: 0.5-1.5 g), synthesis time (X2: 3-7 minutes) and microwave power (X3: 60-100 %). The parameters measured were the conductivity (µS) of the CQDs (Y). The results showed that the mass of activated carbon significantly affected the conductivity of the CQDs solution (P<0.05). Meanwhile, the synthesis time and microwave power factors did not significantly influence the conductivity value (p>0.05). The lack of fit value was found to be 0.82 (p>0.05), proving that the mismatch and non-significance are rejected so that the second-order equation in the conductivity model (µS) has the feasibility of predicting the response to the treatment variables from mass, time, and microwave power. Summarily, RSM can be used to determine the optimal process for synthesizing carbon quantum dots, the optimal conditions obtained were a mass of 1.5 g, a synthesis time of 5 minutes, and an 82% microwave power. [ABSTRACT FROM AUTHOR]

The key benefit of the simulated PZT type-8 material two axis MEMS Scanner for LIDAR Applications is cost and size reduction. Microscopy, LiDAR, and biological imaging all use MEMS technology in conjunction with the proper mirrors and control systems. A low voltage scanning mirror is proposed in this article to take into account applications like LiDAR, particularly for UAV (Unmanned Aerial Vehicle) and gesture recognition. A lever structure made of suitable materials, such as PZT ceramic, can achieve Low Power Consumption although the scanning mirror should have a respectable FOV (Field Of View). To achieve a wide FOV and dual axis MEMS mirror acquisition, the proper activation mechanisms are used. [ABSTRACT FROM AUTHOR]

This article represents a modified particle swarm optimization algorithm named elitist mutation based adaptive PSO (EMAPSO) for enhancing the global search ability of PSO. PSO is one of the most widely used swarm based evolutionary algorithm which has a unique property of faster convergence, moreover, it's also renowned for its strong local search ability. Despite of having faster convergence property, when the functions are highly dimensional and multi-modal, it gets trapped at local optimal solution. Several types of modification have been done to improve the search ability of PSO algorithm. Here, we introduced the global search operator "mutation" to increase the global search ability of PSO with elitist mechanism and adaptive inertia weight and tested it against fourteen well established optimization benchmark functions, eight of them are unimodal and six of them are multi-modal. It has been noticed that incorporation of the mutation operator with elitist mechanism and adaptive inertia weight have increased the search ability significantly and with same parameter settings it gives better results than the basic PSO and GA, while the performance of the proposed algorithm remains consistent with increasing number of modality and dimensionality. [ABSTRACT FROM AUTHOR]

The objective of this study is to investigate the effects of slow and fast pyrolysis on the yields and properties of bio-oils using Macadamia nutshell (MNS) as feedstock. A pilot scale auger pyrolysis reactor which had the facilities of conducting both slow and fast pyrolysis was utilized. The pyrolysis processes were carried out at a temperature of 500 ˚C, the heating rate of 5 ˚C/min, a residence time of 60 mins, and a feedstock particle size of 2 mm. The characterization of feedstock and the produced bio-oils was performed by different techniques like elemental analysis, Gas chromatography-mass spectrometry (GC–MS), and physicochemical properties analysis using appropriate ASTM standards. Proximate and ultimate analysis showed promising prospects of MNS as a feedstock for the pyrolysis process. In the case of slow pyrolysis, the bio-oil yield was found to be 39.7%, whereas the bio-oil yield was 49.5% for the fast pyrolysis process. Significant changes in the peak region of GC–MS were observed for bio-oils produced under two different pyrolysis conditions. It was found from the physicochemical properties analysis that calorific value is higher and water content is lower in the bio-oil produced through fast pyrolysis than the bio-oil produced through slow pyrolysis. Comparison with standard biodiesel properties revealed that produced bio-oils were not suitable for use in engines at this stage. Proper upgradation is required to make it suitable for engine application. Based on these results it can be concluded that the produced bio-oils can be used as fuel in other applications such as in boilers and as additives to produce valuable chemicals. [ABSTRACT FROM AUTHOR]

If sample data disperses information like classification rules, these regulations can need to be combined and fused. This is usually done by combining either the classification outputs, like the classification ensemble, or by incorporating the collection of classification laws by independently weighing them. In this paper, we introduce a new way of assembling classifiers with parameters of classifiers. The technique is based on the use for regression analysis distributions in normative input dimensions of generative probabilistic graders and on nonparametric wave function for continuous. We also spread over classification parameters such as Dirichlet or regular Wishart. These populations are classified as populations of high or second order. We prove that two or more classificatory can be used by multiplying the hyper distributions of variables and drawing simple formulas for the assignment. Any research reveals how this modern approach is described. The primary advantage of this fusion approach is the conservation of hyper distribution in the fusion phase. For starters, the fused components can be used in the organized training steps. [ABSTRACT FROM AUTHOR]

An analysis of steady two-dimensional non-Newtonian Casson fluid flow past an inclined stretching surface in a porous medium with chemical reaction in presence of magnetic field is considered. The governing partial differential equations are reduced to a system of non-linear coupled ordinary differential equations by similarity transformations and are solved them numerically by well-validated Nachtsheim-Swigert shooting method. The influences of various physical parameters on velocity, temperature and concentration profiles are discussed and illustrated graphically. The obtained values for Skin friction coefficient, local Nusselt number and Sherwood number which are of physical and engineering interest are tabulated and found to be in good agreement with previously published results. This study reveals that the concentration profile decreases rapidly with increasing values of chemical reaction parameter. [ABSTRACT FROM AUTHOR]

The unsteady MHD free convection Maxwell nanofluid flow through an exponentially accelerated vertical surface with the presence of radiation and chemical reaction is investigated in this present study. For obtaining numerical solutions, the governing partial differential equations (PDEs) are transformed into dimensionless partial differential equations (PDEs) with the as usual mathematical transformation. Explicit finite difference method (EFDM) is used for numerical solutions where ForTran programing language have been used as the main tool of investigations. The stability analysis technique (SAT) is used for choosing the appropriate values of parameters. Then, the obtained numerical results are affected by this various dimensionless parameters such as magnetic parameter (M), Maxwell parameter (Mx), Schmidt number (Sc), Grashof number (Gr), Lewis number (Le) and so on. The velocity, temperature and concentration profiles along with the skin friction coefficient (Cf), Nusselt number (Nu) and Sherwood number (Sh) are analysed for different perspective. Furthermore, the streamlines and isotherms are discussed for different interesting parameters in this work. Finally, the results are discussed after stability convergence test (SCT) by using graphics software tecplot-9 and comparison of our results with the previous results have been presented in a tabular form. [ABSTRACT FROM AUTHOR]

Theoretical evidence of VO-Zni to be a native donor in bulk ZnO has been under debate. To resolve the issue, we annealed several pieces of as grown zinc rich n-type ZnO thin film having ND ~ 3.26 × 1017 cm-3 grown by molecular beam epitaxy on Si (001) substrate in oxygen environment at 500oC - 800oC, keeping a step of 100oC for one hour, each. Room temperature Hall measurements demonstrated that free donor concentration decreased exponentially and Arrhenius plot yielded activation energy to be 1.2 ±0.02 eV. This value is in an agreement with the theoretically reported activation energy of VO-Zni donor complex in ZnO. [ABSTRACT FROM AUTHOR]

Complexity reduction approach has been used to solve various science and technology problems. In this paper we will discuss the implementation of the approach to solve some hyperbolic equation such as first order hyperbolic problem and the Maxwell Equations. For solving the Maxwell equations, we implement a weighted average fourth order truncation with the complexity reduction approach. The approach shown to successfully reduce the complexity of original method. Results show to increase the speed up of its original method significantly. [ABSTRACT FROM AUTHOR]

In this investigation, TiO2/Ag/TiO2 multilayer-films were deposited on microscope glass slides with varying individual layer thicknesses by radio-frequency reactive magnetron sputtering. Prior to multilayer development, single layers of Ag and TiO2 were deposited and characterized. All the films were prepared at a moderately high pressure at room temperature. It was found that single layer of TiO2 showed anatase polycrystalline structure. It also exhibited high visible transmittance of above 80% and higher refractive index of 2.31 at a wavelength of 550 nm. The indirect optical band gap of the TiO2 films was estimated as 3.39 eV. The Ag single layer films were found to be crystalline with a very high reflectance for IR (Infra-red) light. Finally, the multilayers have been deposited and characterized by X-ray diffraction, UV-visible-IR spectrophotometry, scanning electron microscopy and profilometry. [ABSTRACT FROM AUTHOR]