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Earthen buildings have gained popularity in recent years due to their eco-friendly sustainability approach in both materials and production technique. The materials' availability, ease of construction, and energy efficiency contribute to the utilization of wastes and the reduction of greenhouse gas emissions. Gypsum and shredded plastic wastes are utilized in the production of modified Alker which is an improved earthen building. X-ray Powder Diffraction analysis is performed on the soil to obtain the basic elements in the soil, which show significant Magnesia content. The research studies the mechanical properties in Alker having 6% clay and modified with different percentages of SPW content by dry weight of the soil; 0.5%, 1% and 1.5%. The mechanical properties of matrix modified with 1% SPW show the best results. In addition, linear shrinkage tests are performed on the control and modified sample. The optimum sample modified with 1% SPW show significant reduction in linear shrinkage which is consistent with the crack analysis result performed using Matlab R2018a. It is observed that the optimum sample of 1% SPW has limited crack propagation compared to the other samples. Alker modified with shredded plastic wastes has shown to be a sustainable building material with improved properties.

This paper demonstrates the potency of evolution based optimization techniques in the sense of enhancing the system’s performance. Teaching Learning Based Optimization (TLBO) is a well-known evolutionary algorithm used to optimize the parameters of the PID controller so as to improve the performance of the magnetic levitation system. The TLBO search algorithm is split into two phases, the teacher phase and the learner phase. The teacher phase is comprised of having minimum performance index as compared to learner phase. The learners improve their knowledge on the basis of teacher’s performance. The parameters are tuned while minimizing the performance index of the system. The performance index incorporated in this paper is the integral time weighted square error (ITSE). The corroboration of the above technique is ended by comparing it with the conventional control techniques. Keywords: Magnetic levitation system, PID controller, Teaching learning based optimization, Performance index

In this paper a novel compact microstrip feed square patch antenna with right angled isosceles Koch fractal geometry on its edges is designed for ultra wideband applications. The radiating patch is modified in several steps to achieve a multiband circularly polarized antenna. The fractal antenna is simulated using CST Microwave Studio Simulator. Antenna’s performance is then compared with equilateral Koch, Minkowski and Sierpinski fractal geometries. The suggested antenna is assembled on FR4-epoxy (εr = 4.4) substrate with dimensions 60 × 55 × 1.59 mm3. The developed antenna efficiently operates at 4.3 GHz, 5.0 GHz, 6.1 GHz, 7.4 GHz, 8.9 GHz and 9.2 GHz. Circular polarizations are achieved near four resonant frequencies, which are realized by adding a circle in the middle of the patch. The presented antenna has a good gain, bandwidth, VSWR and axial ratio bandwidth. In this paper, an approach for multiband antennas is proposed. The novelty of the paper lies in the fact that a right angled triangular Koch curve is formed on the edges of the square patch. Keywords: Microstrip patch, Koch fractal, Circular polarization, Ultra wideband (UWB)

This paper addresses the development of the hybrid fault current limiter and interrupting device (HCLID) which can be used successfully as an ultra-fast short-circuit protection means for low voltage AC or DC industrial installations. The main components of the HCLID are as follows: a solid state commutation circuit that can supply a counter current injection from a stand-by pre-charged capacitor, a saturable core reactor as limiting impedance and a fast mechanical contact switch; all are connected in parallel. Through this study, a significantly improved and simplified approach that replaces the half-controllable SCR in the commutation circuit with self-turn-off device, such as IGCT, is presented. The use of high-performance semiconductors (IGCTs) as a commutating device affords reduced recovery voltage, reduced losses, improved reliability and dynamic performance, and fast switching time (in μs). The new approach is emulated in Piecewise Linear Electrical Circuit Simulation (PLECS) and involves a fault detection using rate of current rise rather than the current magnitude and a time delay operating characteristic. The proposed control method can be simply implemented. Different fault cases have been simulated in this paper. Simulation results proved the practicability and validity of the new HCLID. Keywords: Hybrid current limiting interrupting device, Self-turnoff device, Fast mechanical contact switch, Control strategy, PLECS package application

In the current networking field many research works are going on regarding the integration of different wireless technologies, with the aim of providing uninterrupted connectivity to the user anywhere, with high data rates due to increased demand. However, the number of objects like smart devices, industrial machines, smart homes, connected by wireless interface is dramatically increasing due to the evolution of cloud computing and internet of things technology. This Paper begins with the challenges involved in such integrations and then explains the role of different couplings and different architectures. This paper also gives further improvement in the LTE and Wimax integration architectures to provide seamless vertical handover and flexible quality of service for supporting voice, video, multimedia services over IP network and mobility management with the help of IMS networks. Evaluation of various parameters like handover delay, cost of signalling, packet loss,, is done and the performance of the interworking architecture is analysed from the simulation results. Finally, it concludes that the cross layer scenario is better than the non cross layer scenario.

Latent Heat Thermal Energy Storage Systems (LHTESS) containing Phase Change Material (PCM) are used to establish balance between energy supply and demand. PCMs have high latent heat but low thermal conductivity, which affects their heat transfer performance. In this paper, a novel fin array has been optimized by multi-objective Response Surface Method (RSM) based on discharging process of PCM, and then this fin configuration is applied on LHTESS, and comparison between full discharging time by applying this fin array and LHTESS with other fin structures has been carried out. The employed numerical method in this paper is Standard Galerkin Finite Element Method. Adaptive grid refinement is used to solve the equations. Since the enhancement technique, which has been employed in the present study reduces the employed PCM mass, maximum energy storage capacity variations have been considered. Therefore phase change expedition and maximum energy storage capacity have been considered as the objectives of optimization and the importance of second objective is indicated which is proposed as the novelty here. Results indicate that considering maximum energy storage capacity as the objective of optimization procedure leads to efficient shape design of LHTESS. Also employing optimized V-shaped fin in LHTESS, expedites discharging process considerably in comparison with the LHTESS without fin.

This paper addresses the problem of overcurrent relays (OCRs) coordination in the presence of DGs. OCRs are optimally set to work in a coordinated manner to isolate faults with minimal impacts on customers. The penetration of DGs into the power system changes the fault current levels seen by the OCRs. This can deteriorate the coordinated operation of OCRs. Operation time difference between backup and main relays can be below the standard limit or even the backup OCR can incorrectly work before the main OCR. Though resetting of OCRs is tedious especially in large systems, it cannot alone restore the original coordinated operation in the presence of DGs. The paper investigates the optimal utilization of fault current limiters (FCLs) to maintain the directional OCRs coordinated operation without any need to OCRs resetting irrespective of DGs status. It is required to maintain the OCRs coordination at minimum cost of prospective FCLs. Hence, the FCLs location and sizing problem is formulated as a constrained multi-objective optimization problem. Multi-objective particle swarm optimization is adopted for solving the optimization problem to determine the optimal locations and sizes of FCLs. The proposed algorithm is applied to meshed and radial power systems at different DGs arrangements using different types of FCLs. Moreover, the OCRs coordination problem is studied when the system includes both directional and non-directional OCRs. Comparative analysis of results is provided.

At present, electrospinning technology is a versatile and simple method for generating nano-scale membranes, and it provides attractive solutions in solving environmental problems and many energy problems. However, such films generally have low mechanical properties which limit their use in industry. Nanocellulose with excellent mechanical properties, high specific surface area, and renewable nature is an ideal green reinforcing material. In this paper, the cellulose nanocrystals (CNC) coatings on electrospun polyamide 6 (PA6) were prepared via coating method and explored as potential high-performance reinforced materials. The extraction of CNC and the performance of the composite membranes were studied by calculating the yield, scanning electron microscopy, 3D imaging, mechanical testing, and thermogravimetric analysis. Results show that the yield of CNC is impacted by various factors among which acid concentration is the most important. The CNC/PA6 composite film shows lower porosity and higher surface roughness than the pure PA6 membrane. With the increase of CNC concentration, lower porosity and higher surface roughness are obtained. With CNC coatings, tensile strength and Young s modulus of PA6 increase dramatically, while the tensile strain decreases obviously. The Young s modulus of the composite film has been increased by 250%. The composite membranes reveal high mechanical strength and low porosity, which can be applied infiltration and packaging.

Oil palm shell (OPS), one of the most abundantly produced solid bio-wastes in Southeast Asia, is yielded by crushing the oil palm kernel during palm oil extraction in the palm oil mills. Approaches have been devoted to developing the use of OPS as reinforcing filler in polymer composites to enhance the functional properties of composites. For OPS to be effective for reinforcing materials, its role and beneficial effects on the improvement of composites’ properties need to be investigated. However, not many studies have discussed the potentials of incorporating OPS in thermoplastic and thermoset polymer composite applications. This paper summarises the enhancement of composite characteristics, including physical, mechanical, thermal, water barrier and biodegradability properties. Properties of OPS that make it a good candidate as a reinforcing filler, such as tensile strength, impact strength, elongation, Young’s modulus, morphological and water absorption, are discussed in detail. In addition, the application of its derivative, challenges, and outlook are also discussed.

This paper presents a new approach for Real-Time Application of Profit Based Unit Commitment using Memory Management Algorithm. The main objective of the restructured system is to maximize its own profit without the responsibility of satisfying the forecasted demand. The Profit Based Unit Commitment (PBUC) is solved by Memory Management Algorithm (MMA) in Real-Time Application. MMA approach is introduced in this paper considering power and reserve generation. The proposed method MMA uses Best Fit and Worst Fit allocation for generator scheduling in order to receive the maximum profit by considering the softer demand. Also, this method gives an idea regarding how much power and reserve should be sold in markets. The proposed approach has been tested on a power system with 2, 3, and 10 generating units. Simulation results of the proposed approach have been compared with the existing methods.

The presented work aims at identifying the potentials of mobile social networking and geo-coding to promote cities, as well as to test their usefulness as decision support systems for planners. Alexplore is an application that was developed by planners rather than IT specialists using emerging web 2.0 technologies. Penetration rates of mobile internet access, as well as smartphone usage ensure a solid base for such applications worldwide as well as in Egypt. This paper traces the influence of social networks on tourism and city planning through the past decade and pinpoints its contributions and constraints. It highlights the potentials of social networks for tourists, planners, and citizens. Through the paper, the concept, technology, functionality, and limitations of Alexplore are thoroughly explained. In spite of current shortcomings, Alexplore provides solid benefits for its different stakeholders. Few concerns occur due to the proper application of ethical rules to social networking as well as due to fear of over dependency on such techniques. It is believed that with the development of the technology, many currently functional issues will be alleviated. Last, Alexplore should not be regarded as a replacement for traditional planning methods, but rather a useful augmentation to it.

For smart cities, the successful large-scale implementation of solar PV technology, Quality Certification and Standards are mandatory. The International Electrotechnical Commission (IEC) is a global organization for standardization consisting of all IEC national committees. The IEC PV standards comprise IEC technical committee 82 solar PV Energy System (IEC TC82) which develops and adopts all Photovoltaic related standards. There are nearly 80 standards applicable to photovoltaic and five working groups in IEC TC82. For necessary safety requirements ‘Quality and Standards’ technologically need to be revised and up to date. This paper presents PV standards developed by various technical committees worldwide, mainly focusing on various IEC PV standards, gaps identified by them and the recommendations provided by the committee in recent times. The breakup costs of the various sub-systems of a PV installation with an illustrative example for India is also discussed. It is intended to provide a guideline for consumers and investors, opting for solar PV installations.

Sepiolite (Si12Mg8O30(OH,F)4].(H2O)4·8H2O) is a valuable filler with an enormous capacity to be used in thermoplastic composites, substituting costly reinforcing fillers, such as graphene and CNTs. Sepiolite strengthened polymers nanocomposite materials have encouraged the field of research and ventures because of their strengthening ability and bio-compatibility in polymer composites. Sepiolite shows remarkable characteristics over various fillers due to its higher specific surface area and channel type structure. Numerous investigations were performed to decide different properties of Sepiolite strengthened polymer composites in various applications, for example, tensile strength, flexural strength, impact strength, stiffness, thermal, flammability, thermo-mechanical, and morphological. This review paper focuses on the mechanical and thermal properties of sepiolite strengthened polymer nanocomposites. Generally, it can be determined that the properties of sepiolite loaded thermoplastic polymer composites mainly depend on filler content, matrix, bond interaction, shape, size of sepiolite particles. Further assessment and development are required to expand its utilization in several applications. These comprise the utilization of nano-size sepiolite made synthetically as functionalized filler in thermoplastics.

The mixed convection flow and heat transfer over an exponentially stretching/shrinking vertical surface in a hybrid nanofluid is considered in this paper. Copper (Cu) and alumina (Al2O3) are employed as the hybrid nanoparticles while water as the base fluid. It is shown that the heat transfer rate enhances in the presence of nanoparticles. However, the reduction in heat transfer rate is observed for the shrinking case, caused by the imposition of stronger suction at the boundary. It is also found that the bifurcation of the solutions occurs for both stretching and shrinking regions as well as for both buoyancy aiding and opposing flows. The temporal stability analysis shows that only one of the solutions is stable and thus physically reliable as time evolves.

It is an undeniable fact that heritage buildings are a valuable asset for society, it reveals their achievements over the years. Therefore, the need to conserve built heritage has become an increasingly urgent case to experts and the community, they exploit any possible tool to achieve this aim. However, the concept of heritage conservation has completely changed due to the new technologies and inventions which opened up new opportunities to the conservation process of built heritage. This paper focuses on the theoretical parametric approach in generating digital heritage models which will help in the restoration and reconstruction process. A library of parametric heritage models will be designed from architectural books and historic scripts which will then be embedded in a new plug-in for BIM software. This new plug-in will provide multiple solutions for historical buildings which facing certain problems while using manual modelling methods in restoration and reconstruction processes, it will also automate the modelling process by using parametric modelling techniques. Keywords: Built heritage, Conservation, Digital heritage models, New plug-in, Parametric approach

The historical writings were found on stones, palm leaves, cloth, etc. This paper deals with the identification of Telugu Palm leaf characters by acquiring a additional 3D feature on palm leaves. The background of these manuscripts is identical to the writings on them. Removing background from such scripts is a tedious task. This is achieved with the 3D feature depth in the current work. With the help of this 3D feature, an improved classification rate is also achieved. Keywords: Historical manuscripts, 3D feature, Cell-based directions, Optimization

In this paper, New asymmetric cascaded half H bridge multilevel inverter MLI is proposed. It is driven from the conventional asymmetric cascaded half H Bridge multilevel inverter. Thus, the proposed topology inherits its simplicity, flexibility and modularity in both construction and control. By proper choice of the input DC sources values and interconnection, proposed topology can eliminate the need for polarity generation circuit which normally associated with the cascaded half H-bridge. Therefore, reduces number of switches that require high blocking voltage. The selective harmonic elimination SHE method is applied to generate switching pattern to eliminate harmonics inherently associated with MLI. The proposed topology switching pattern naturally reduces component’s voltage stress, switching losses and finally decrees MLI size and cost. Mathematical expressions and analysis have been driven as well as comparison with other topologies. The validity of the proposed topology is verified with Matlab/Simulink model and then a prototype is built and experimental results are presented. Keywords: Single-phase inverter, Multi-level inverter, H bridge inverter, Total Harmonics Distortion (THD), SHE

Buildings are responsible for around 50% of energy consumption around the world and most of this because of spaces design, low heat isolation building material, occupant behavior and non-efficient architectural treatments. This have large impact on heating, cooling and ventilation demand, energy consumption of lighting and appliances, and building attitude. This paper aims to focus on passive treatments in Wakala Buildings in Cairo and how far they meet the LEED Criteria which considered the widest spread rating system in the world. By studying wakala in Cairo, there are a lot of passive treatments and energy efficiency that could be found in examples trough surveying and analyzing. Besides the environmental treatments through the natural materials and façade architectural treatments, measuring phase is to declare the efficiency of the wakala through temperature decline between outdoor and indoor. Also, identifying the thermal comfort for occupants indoors. After measuring the wakala buildings, it is the role of applying the criteria of LEED to find out how far wakala meet the LEED rating system criteria. After all, building technologies used in wakala in the field of passive design and energy efficiency would be clear and what is needed for wakala to have a LEED certification. Keywords: Energy awareness, Historical commercial buildings, LEED, Wakala buildings

The cyclic heave and settlement of expansive soils could be the main reason to considerable damages to the structures, roads and highways. In Egypt there are many regions containing such expansive soils especially at the desert lands. The remote areas are used now for establishing many projects such as (wind farms, solar plants, irrigation projects and nuclear power plants). The use of a mixture of lime-treated swelling soil mixed with potable water to overcome the swelling potential of these soils is available in many countries especially in U.S.A. For the projects located adjacent to the coasts of Sea, the sea water is available instead of potable water. This paper presents an experimental and field case study on the lime-treated soil but mixed with sea water instead of potable water. The effect of using sea water instead of potable water on the swelling behavior, engineering properties, and the consolidation parameters were studied. On the other hand, this research deals with the behavior of the lime-treated soil in swelling state as well as in consolidation state. Tests results showed that there are significant reductions in the swelling potential, engineering properties, and the consolidation parameters in case of using sea water instead of potable water as mixing water. The environmental and economic impact gained from such process was put into consideration. Keywords: Lime-treated soil, Swelling, Consolidation, Potable water, Sea water

Recently, diabetes becomes the widespread and major disease in the world. In this paper, we propose a novel hybrid classifier for diabetic diseases. The proposed hybrid classifier named Logistic Adaptive Network-based Fuzzy Inference System (LANFIS) is a combination of Logistic regression and Adaptive Network-based Fuzzy Inference System. Our proposed intelligent system does not use classifiers to continuous output, does not delete samples with missing values, and does not use insignificant attributes which reduces number of tests required during data acquisition. The diagnosis performance of the LANFIS intelligent system is calculated using sensitivity, specificity, accuracy and confusion matrix. Our findings show that the classification accuracy of LANFIS intelligent system is about 88.05%. Indeed, 3–5% increase in accuracy is obtained by the proposed intelligent system and it is better than fuzzy classifiers in the available literature by deleting all samples to missing values and applying traditional classifiers to different sets of features. Keywords: Diabetes, Intelligent system, Missing value, ANFIS, Logistic regression

Harmonics generated by the nonlinear loads is a serious concern to the power system engineers as it adversely affects the power quality of the system. Recently, many findings focus on reducing the harmonics by introducing various topologies of the filter at the load end. This paper introduces a new concept of reducing current harmonics at the source side of induction motor using SAF in ANN controller. The vector control approach has been adopted for improving the dynamic performance of three phase induction motors. The voltage source inverter fed induction motor is considered as a nonlinear load. The mathematical model of three phase induction motor has been developed and the source current harmonics is reduced using PI and ANN controller. The hardware implementation of induction motor drive with shunt active filter on the supply side has been done. Also, the model is simulated using MATLAB/Simulink software and validated with the hardware results. Keywords: Artificial neural network, PI controller, Shunt active filter, Total harmonic distortion, Vector control of induction motor

In this paper, a simplified 2½-degree of freedom time-domain numerical method with non-linearity is developed, presented in detail and validated for simulating parametric roll. The method is termed 2½-degree of freedom since; it first linearly couples heave and pitch via a three-dimensional frequency-domain pulsating source method. The roll equation of motion is – then – solved in the time domain with, non-linear damping and non-linear parametric excitation taken into account and formulated in terms of heave-pitch-wave profile influence on roll. In other words, heave and pitch motions influence roll but roll motion does not influence heave and pitch back hence, the term 2½-degree of freedom. The mathematical formulation of the proposed method is presented in detail and has been developed into an in-house numerical model. Subsequently, the numerical model is applied to a modern container ship. Experimental results from the literature are utilized for validation. Predicted results show very good agreement with experiments and demonstrate the ability of the proposed method to accurately capture the influence of various parameters affecting parametric roll. Keywords: Parametric roll, 2½-Degree of freedom, Time domain analysis, Modern hull-forms, Regular waves

In Mobile Ad hoc Network (MANET), Congestion is considered as the significant issue of concern as they influence router based network functionalities achieved by the intermediate nodes participating in routing. Congestion generally occurs due to limited availability of network resources such as bandwidth and energy which lead to significant packet loss, end-to-end delay and communication overhead. Hence, the core objective of congestion control algorithms was to utilize the allocated network resources and to maintain the load below an acceptable threshold capacity. This paper proposes a Dynamic multi-stage Tandem Queue modeling-based Congestion Adaptive Routing (DTQCAR) based on the estimations of average threshold level of congestion. The decision of congestion policing is achieving the current congestion level and sending warning messages to all their neighbors for dynamic adjusting of packets forwarding. The estimation of average threshold level is based on Dynamic multi-stage Tandem Queue modeling that inspires stochastic probability. Depending on the elucidated stochastic factors, neighbors attempt to locate a congestion-free alternative path to the destination. The simulation results also confirm that DTQCAR on average showed a better performance of 13%, 17% and 19% than the existing LBCAR, DCDR and EDAPR congestion control algorithms in terms of packet delivery ratio. Keywords: Stochastic factors, Multi-stage tandem queue, Congestion, Average queue length, Stochastic probability

This paper deals with conjugate heat transfer from a rectangular fin. The problem consists of mild steel (250 × 150 × 6 mm) fin placed vertically on aluminium base (250 × 150 × 4 mm). The aluminium plate is subjected to an unknown heat flux at the base. The fin set-up is modelled using ANSYS fluent 14.5. The fin geometry is surrounded by extended domain filled with air so as to account for natural convection conjugate heat transfer. Grid independence study is carried out to fix the number of grids. A simple correlation using Asymptotic Computational Fluid Dynamics (ACFD) is developed and the same is used as a forward model to obtain the temperature distribution considering heat flux as the input. The problem is treated as an inverse problem in which a non-iterative method, ANN is used as the inverse model to estimate the unknown heat flux from the information of temperature. The results of the forward model and the ANN predicted values are in close agreement with error less than 1%. Effect of noise on the unknown parameter is also studied extensively. Keywords: Conjugate, Fin, ACFD, ANN, Surrogated, Noise

Due to the type of applications, wireless sensor nodes must always be energy efficient and small. Hence, the presence of constraints such as the limitation of energy resource is inevitable. So far, several studies have been carried out in order to present solutions for the reduction in energy consumption. In the meantime, clustering is given prime significance as an efficient method, which means partitioning network into distinct areas and is a way for managing nodes communication. Two well-known methods, LEACH and HEED in this field have had a great performance in energy saving and quality of services in WSNs. In this paper, a new method of clustering and selection of cluster heads has been proposed based on energy efficiency and due to residual energy of each node by applying weighting coefficients. The results of analyses and simulations and comparison of proposed method by LEACH and HEED algorithms show that the proposed method has significant impact on energy efficiency and performance improvement of the sensor network. Keywords: Clustering, Lifetime, LEACH, HEED, Residual energy, Thresholding, WSN

In this research paper, a new application of Adaptive Neuro-Fuzzy Inference System (ANFIS) to the control of greenhouse climate system is introduced. To cope with the large amount of uncertainties present in such systems and in order to improve the system performance, a Genetic Algorithm (GA) is used to adapt the controller parameters such as the number and shape of membership functions employed and scaling factors. Simulation results showed that the proposed control architecture is able to provide smooth control regardless of the continuously changing environmental conditions and the complexity of the plant. The performance of the proposed controller has been assessed against other traditional controllers and has been found to outperform its counterparts. © 2015 Faculty of Engineering, Alexandria University. Production and hosting by Elsevier B.V. This is an open access article under the CC BY-NC-ND license ( http://creativecommons.org/licenses/by-nc-nd/4.0/ )

Several sensor nodes in the wireless network collect the data rigorously which aids in many of the applications. The network with high and the consistent data load is the only requirement of the wireless sensor networks. Due to the limited sources of the network and the high data loads, networks may be affected by congestion. Congestion is a highly objectionable issue which leads to information loss and the deprived performance of the wireless sensor networks. In this paper, an adaptive cuckoo search based optimal rate adjustment (ACSRO) for the congestion avoidance and control is proposed. The rate adjustment regulates the share rate of the node to mitigate the congestion. The performance of the proposed rate optimization approach is evaluated using the evaluation metrics such as throughput, delay, normalized packet loss, normalized queue size, and congestion level. The results of the proposed rate optimization show that the congestion is compacted and the performance of the WSN is improved. Keywords: Wireless sensor networks, Cuckoo search, Congestion avoidance and control, Congestion levels

Reciprocating compressors are one of the most used types of compressors with wide applications in industry. The most common failure in reciprocating compressors is always related to the valves. Therefore, a reliable condition monitoring method is required to avoid the unplanned shutdown in this category of machines. Acoustic emission (AE) technique is one of the effective recent methods in the field of valve condition monitoring. However, a major challenge is related to the analysis of AE signal which perhaps only depends on the experience and knowledge of technicians. This paper proposes automated fault detection method using support vector machine (SVM) and AE parameters in an attempt to reduce human intervention in the process. Experiments were conducted on a single stage reciprocating air compressor by combining healthy and faulty valve conditions to acquire the AE signals. Valve functioning was identified through AE waveform analysis. SVM faults detection model was subsequently devised and validated based on training and testing samples respectively. The results demonstrated automatic valve fault detection model with accuracy exceeding 98%. It is believed that valve faults can be detected efficiently without human intervention by employing the proposed model for a single stage reciprocating compressor. Keywords: Condition monitoring, Faults detection, Signal analysis, Acoustic emission, Support vector machine

Increasing volumes of the international seaborne trade and new regulations on vessel emissions require liner shipping companies to enhance efficiency of their operations to remain competitive and in the meantime comply with the established restrictions on emissions that are produced by vessels. This paper presents a novel mixed integer nonlinear mathematical programming model for the green vessel scheduling problem with transit time requirements in a liner shipping route with “Emission Control Areas”, which not only enforces constraints on the quantity of emissions that are produced by vessels within “Emission Control Areas”, but also captures the cargo transit time requirements. The model’s objective aims to minimize the overall route service cost. A number of linearization techniques are proposed for linearizing the original nonlinear problem. The dynamic secant approximation procedure is used to solve the linearized problem. A set of numerical experiments are performed to evaluate the efficiency of the proposed solution approach and assess the effect of introducing both emission constraints and cargo transit time requirements on design of vessel schedules. Keywords: Marine transportation, Energy efficiency, Green vessel scheduling, Emission Control Areas, Emission limitations, Cargo transit time requirements

Cognitive radio wireless networks CRNs have been considered as an efficient communication paradigm to the utilization of scarce spectrum. The main purpose of channel reservation of dynamic spectrum access (DSA) is to access these idle channels intelligently which are specialized for primary users (PUS) to be used by unlicensed users temporarily, which are called secondary users (SUS) without causing critical interference to the licensed userâs activity. In this paper, continuous-time Markov chain paradigm is improved via channel reservation to show the best usage of the radio spectrum bands, and the transition matrix are deduced for the proposed model. Moreover, the probability state vector is proved by performing steady state analysis. The deduced expressions of the suggested model are illustrated in the numerical results section. Keywords: Cognitive radio networks, Dynamic spectrum access, Channel reservation, Continuous-time Markov chain, Steady-state analysis

This paper presents experimental modal analysis of non-rotating tires under different boundary conditions. A test rig with four guides in vertical (radial) direction and two guides in axial direction was designed to support the tire-rim assembly with a free support. The setup permits to carry out the experiments on the grounded supported tire-rim assembly while changing the value of the static load acting on the wheel axis. Under static load condition, it is found that, tire deflection depends on the applied static radial force in a hysteresis manner and a third-order polynomial was used to fit the data during loading and unloading conditions. The relationship between static stiffness in radial direction and tire deflection is nonlinear and depends on loading/unloading conditions for different tire pressures. The response of the tire is quite similar to the response of viscously damped mass system for impulse force which is provided by an impact hammer. The results show that the system modal parameters can be obtained respective of loading or unloading conditions with a maximum difference of 1.992% for frequency values and 3.66% for damping values. This study has a practical value for the description of mechanical properties of tires. Keywords: Tire measurements, Modal analysis, Boundary conditions, Vibration response

Self compacting concrete (SCC) is a highly flowable type of concrete that spreads into form without the need of mechanical vibration. This paper presents a comparative study between two methodologies which have been applied on two different data sets of SCC mixtures, which were gathered from the literature, using artificial neural network (ANN). The two methodologies aim to get the best prediction accuracy for the SCC ingredients using the 28-day compressive strength and slump flow diameters as inputs of the ANN. In the first methodology, the ANN model is constructed as a multi input â multi output neural network with the six ingredients as outputs. In the second methodology, the ANN model is constructed as a multi input â single output neural network where the six ingredient outputs are predicted separately from six different neural networks of multi input â single output type. Also, the influence of the mixes homogeneity on the prediction accuracy is investigated through the second data set. The results demonstrate the superiority of the second methodology in terms of accuracy of the predicted outputs. Moreover, the uniformity of the training data assures the accuracy of the predicted ingredients. Keywords: Self compacting concrete (SCC), Artificial neural network (ANN), Concrete mix design, Concrete compressive strength, Slump flow

A Magneto-Rheological (MR) fluid disc brake is a device that transmits a torque by the shear force of MR fluid. The fluid is inserted between the rotating and fixed discs and a magnetic field is imposed on the fluid. In this paper, a complete test rig for an MR fluid disc brake is introduced. Experiments are conducted to measure the braking torque and speed of shaft during braking process and the results are presented at different voltage input to the brake. Also theoretical analysis for both MR brake and the mechanical system is developed and is solved numerically using finite difference method and Matlab software. Effect of current input to the MR brake, viscosity of fluid and design parameters is taken into consideration. A validation of the theoretical results with CFD model is introduced. The experimental results are performed and both angular velocity and the braking torque are obtained as responses during the braking process. A comparison between braking torques obtained from theoretical and experimental work shows agreement when voltage is 2 V at speed of 150 rpm and also agreement when voltage is 2 and 3 V at speed of 250 rpm.

This paper presents a novel hexagon shape bow-tie antenna for implantable bio-medical application at a frequency ranging from 2.4 GHz to 2.48 GHz of ISM band. In order to achieve high frequency response the proposed antenna is designed with CPW feed. Alumina ceramic ( Al 2 O 3 ) is used as the substrate material with 1 mm thickness and the dielectric constant is 9.8. The proposed antenna has the total size of 10 ∗ 10 ∗ 1 mm which is located at human tissues such as muscle, fat and skin and some of the parameters such as gain, return loss, radiation pattern and VSWR are measured. The main advantage of the proposed system is it has reduced size with increased accuracy. The proposed antenna possesses the return loss of −29 dB at 2.43 GHz. Thus the proposed hexagon shape bow-tie antenna can be employed for several implantable applications.

This paper shows the implementation of a fuzzy controller applied for magnetic levitation, to make this, the characterization of the magnetic actuator was computed by using ANSYS® analysis. The control law was a Mamdani PD implemented with two microcontrollers, to get a smooth control signal, it was used a model reference. A learning scheme was used to update the consequents of the fuzzy rules. Different reference signals and disturbances were applied to the system to show the robustness of the controller. Finally, LabVIEW® was used to plot the results.

In this paper, a brief overview of real time implementation of next generation Robust, Tracking, Disturbance rejecting, Aggressive (RTDA) controller and Model Predictive Control (MPC) is provided. The control algorithm is implemented through MATLAB. The plant model used in controller design is obtained using system identification tool and integral response method. The controller model is developed in Simulink using jMPC tool, which will be executed in real time. The outputs obtained are tested for various constraint values to obtain the desirable results. The implementation of Hardware in Loop is done by interfacing it with MATLAB using Arduino as data acquisition unit. The performance of RTDA is compared with those of MPC and Proportional Integral controller.

This paper aims to optimize the distribution of chord and twist angle of small wind turbine blade in order to maximize its Annual Energy Production (AEP). A horizontal-axis wind turbine (HAWT) blade is optimized using a calculation code based on the Blade Element Momentum (BEM) theory. A difficult task in the implementation of the BEM theory is the correct representation of the lift and drag coefficients at post-stall regime. In this research, the method based on the Viterna equations was used for extrapolating airfoil data into the post-stall regime and the results were compared with various mathematical models. Results showed the high capability of this method to predict the performance of wind turbines. Evaluation of the efficiency of wind turbine blade designed with the proposed model shows that the optimum design parameters gave rise to an increase of 8.51% in the AEP rate as compared with the corresponding manufactured operating parameters.

In this paper, a solar liquid desiccant air conditioning (SLDAC) system has been studied. The effect of changing evacuated tube collector area on the performance of the SLDAC system was fulfillment. This inquest was done over all a year in Borg Al-Arab city located in the Northern region of Egypt. Meteorological data, such as hourly average solar radiations and temperatures, were needed to achieve this research. The hourly cooling loads were determined by using Hourly Analysis Program (HAP) 4.7. These loads are wall, illumination, people, and equipment loads. Then, the hourly differences of different parameters such as amount of water absorbed in conditioner, amount of water desorbed in regenerator, hot water temperature and coefficient of the performance were calculated. In addition, the maximum solar thermal energy was determined to meet the regeneration demand according to the hourly average solar radiation data. For 220 m 2 evacuated tube collector area, the maximum required heat energy is obtained as 38,286 kW h on December, while using solar energy, will save energy by 30.28% annual value.

Transportation electrification has undergone major changes since the last decade. Success of smart grid with renewable energy integration solely depends upon the large-scale penetration of plug-in hybrid electric vehicles (PHEVs) for a sustainable and carbon-free transportation sector. One of the key performance indicators in hybrid electric vehicle is the State-of-Charge (SoC) which needs to be optimized for the betterment of charging infrastructure using stochastic computational methods. In this paper, a newly emerged Accelerated particle swarm optimization (APSO) technique was applied and compared with standard particle swarm optimization (PSO) considering charging time and battery capacity. Simulation results obtained for maximizing the highly nonlinear objective function indicate that APSO achieves some improvements in terms of best fitness and computation time.

Earlier reports indicate that ethanol/bioethanol can replace conventional diesel fuel by 15%, when it is emulsified with diesel and used as an alternative fuel in a compression ignition (CI) engine. In this study, initially BMDE15, a bioethanol emulsion containing 15% bioethanol, 84% diesel and 1% surfactant was characterised for its fuel properties and compared with those of diesel fuel properties. The numerical value indicates the percentage of bioethanol in the BMDE15 emulsion. For the investigation, bioethanol was obtained from the Mahua Indica flower which was collected from the Madhuca Indica tree, and it was produced from fermentation process using Saccharomyces cerevisiae. Further, the BMDE15 emulsion was tested in a single cylinder, four stroke, air cooled, DI diesel engine developing a power of 4.4 kW at a rated speed of 1500 rpm. Two important combustion parameters: cylinder pressure and ignition delay, and two important emission parameters: nitric oxide (NO) and smoke emissions were determined and compared with those of diesel operation at all loads. The experimental results were validated using mathematical modelling, and the analysis of the results is presented in this paper. Web of Science 54 4 1002 993

This paper presents and analyzes the experimental and numerical results of a series of pullout tests under monotonous loading performed on five steel strips presenting various forms of roughness (smooth, ribbed, punched, W-shaped, chain) and embedded in the same dry sand massif constituting the backfill. The pullout tests were conducted by means of a small-scale model and the calculations carried out by using a finite elements computer program. Obtained results show a good agreement between the experimental and numerical data. They show in addition that the rough strips are more advantageous than the smooth strip. Among the rough strips considered, chain is most relevant.

Tower crane is increasingly becoming one of the key components of temporary site layout facilities in most construction projects. Determining the location of tower crane is an essential task of layout planning, which is also the central focus of this study. The optimization of tower crane location depends on many interrelated factors, including site constraints, shape and size of the buildings, type and quantity of required materials, crane configurations, crane type, and construction site layout. These factors vary from one project to another, resulting to complicated site layout strategies and approaches. This fact makes the crane location problem impractical to be solved depending on experience of practitioners only which was gained by assuming and through trial and error. This paper aimed at developing an optimization model to solve tower crane location problem in construction sites. The objective was to minimize the total transportation time. Genetic Algorithms (GA) optimization technique is utilized to solve the problem. A numerical example is presented to test and validate the results obtained by the model.

Battery Electric Vehicle (BEV) is a promising candidate in reducing air pollution and fossil fuel dependencies. It is a growing market for the automobile manufacturers. Although there are many advantages of driving a BEV, it is still not widely accepted in the market due to the limited driving range. Other than just improving the technologies that drive the vehicle, an additional range estimation system can calm the ‘range anxiety’ caused by the limited range of BEVs. Merely predicting the range based on the state of charge of the battery, the average driving speed, and the average power consumption is inadequate. This paper proposes a new range estimator, the dynamic range estimator, which also takes into account the driving behavior, in addition to the slopes of the trip for its energy estimation. The driving behavior is obtained based on the response to speed error and the time delay between throttle pedal and brake pedal switching. In this way, the driving behavior is a fixed response for any driving speeds on the same route thus, allowing the energy consumption to be compared for different speeds.

This paper addresses the influence of using Portland limestone cement “PLC” on cement hydration by characterization of its microstructure development. The European Standard EN 197-1:2011 and Egyptian specification ESS 4756-1/2009 permit the cement to contain up to 20% ground limestone. The computational tools assist in better understanding the influence of limestone additions on cement hydration and microstructure development to facilitate the acceptance of these more economical and ecological materials. μic model has been developed to enable the modeling of microstructural evolution of cementitious materials. In this research μic model is used to simulate both the influence of limestone as fine filler, providing additional surfaces for the nucleation and growth of hydration products. Limestone powder also reacts relatively slow with hydrating cement to form monocarboaluminate (AFmc) phase, similar to the mono-sulfoaluminate (AFm) phase formed in ordinary Portland cement. The model results reveal that limestone cement has accelerated cement hydration rate, previous experimental results and computer model “cemhyd3d” are used to validate this model. Keywords: μic model, Cemhyd3d model, Microstructure, Particle size distribution “PSD”

This paper describes the modeling of polarization curves not exhibiting a Tafel region using Excel spreadsheets. Carbon steel in aerated NaCl unbuffered solutions was studied applying a linear potential sweep technique. Current–potential curves were obtained from linear potential sweep at a rate of 10 mV s−1 in un-buffered 0.1, 0.4 and 0.9 M NaCl solutions, at a constant temperature of 25 °C and potential sweeps that were conducted in a potential range −1.0 to 0.4 V vs. Ag/AgCl.

The cutting stock problem (CSP) is one of the significant optimization problems in operations research and has gained a lot of attention for increasing efficiency in industrial engineering, logistics and manufacturing. In this paper, new methodologies for optimally solving the cutting stock problem are presented. A modification is proposed to the existing heuristic methods with a hybrid new 3-D overlapped grouping Genetic Algorithm (GA) for nesting of two-dimensional rectangular shapes. The objective is the minimization of the wastage of the sheet material which leads to maximizing material utilization and the minimization of the setup time. The model and its results are compared with real life case study from a steel workshop in a bus manufacturing factory. The effectiveness of the proposed approach is shown by comparing and shop testing of the optimized cutting schedules. The results reveal its superiority in terms of waste minimization comparing to the current cutting schedules. The whole procedure can be completed in a reasonable amount of time by the developed optimization program.

This research is concerned with detecting defects in software requirements specification. Motivated by both the problem of producing reliable requirements and the limitations of existing taxonomies to provide a satisfactory level of information about defects in the requirements phase, we focus on providing a better tool for requirements analysts. Only few attempts have been made to classify defects and defect detection techniques. Scattered knowledge about defects and defect detection techniques needs compilation and re-evaluation in order to enhance the ability to discover defects in the requirements phase. Toward this end, this work presents a taxonomy of requirements defects and the causes of their occurrences. The purpose is to reach a comprehensive understanding of both the sources of the problem and the solutions of possible defects and defect detection techniques. The taxonomy’s design is based on the analysis of each defect and its sources. In addition, this paper proposes a combined-reading technique for defects in requirements. The proposed technique avoids the shortcomings of other reading techniques. The result of applying the recommendations of this work specifically improves the quality of the requirements specification and generally software quality.

Effective utilization plans for various resources at a container terminal are essential to reducing the turnaround time of cargo vessels. Among the scarcest resources are the berth and its associated cranes. Thus, two important optimization problems arise, which are the berth allocation and quay crane assignment problems. The berth allocation problem deals with the generation of a berth plan, which determines where and when a ship has to berth alongside the quay. The quay crane assignment problem addresses the problem of determining how many and which quay crane(s) will serve each vessel. In this paper, an integrated heuristics-based solution methodology is proposed that tackles both problems simultaneously. The preliminary experimental results show that the proposed approach yields high quality solutions to such an NP-hard problem in a reasonable computational time suggesting its suitability for practical use.

Sensorless induction motor (IM) drives are widely used in industry for their reliability and flexibility, particularly in hostile environment. However, the performance of many of previously developed observer based speed sensors in very low speeds of IM drives was not satisfactory. In this paper, the model reference adaptive system (MRAS)-based speed and stator resistance estimators of IM drives fed by four switch three phase inverter (FSTPI) in the critical low and zero speed region of operation are presented. The estimated speed is used as feedback in a vector control system. The MRAS approach has the immediate advantage that the model is simple, eliminates the produced error in the speed adaptation, and more stable and robust. Simulation results of the MRAS speed observer based sensorless field-oriented induction motor drives fed by FSTPI are presented at critical low and zero speed region of operations. The performances of the MRAS technique is evaluated in indirect vector control system. Experimental results validate the proposed approach.