bluuebunny/crossref_metadata_2025 huggingface dataset:
Power Flow Analysis of Weakly Meshed Distribution Network Including DG
Authors: Al-Sakkaf A. , AlMuhaini M.
Published: November 2020

Power flow is one of the essential studies in power system operation and planning. All steady-state parameters for power distribution systems, such as bus voltage magnitudes, angles, power flows, and power losses, can be calculated by conducting power flow analysis. Distribution system features differ from those of transmission system, rendering conventional load flow algorithms inapplicable. In this paper, three distribution power flow techniques are presented and tested to evaluate their performance when applied to a networked distribution system including distributed generation (DG). These are the distribution load flow (DLF) matrix, the enhanced Newton Raphson (ENR), and the robust decoupled (RD) method. IEEE 33-bus system is adopted for implementing the above methods. Radial and weakly meshed configurations are applied to the tested system with DG inclusion to investigate their influence on the power flow study findings.
PFC Control for LED Lamp Driver Using Sensorless Predictive Current Controller
Authors: Zaky M. S. , Azazi H. Z. , Touti E.
Published: November 2020

Light-emitting diodes (LEDs) have recently become of utmost significance to replace conventional lighting sources. Power factor correction (PFC) control of LED lamps requires three sensors which cause more cost, increase time delay, and increase noise, thus reducing drive reliability. Alternative methods to estimate the inductor current instead of its measurement are mandatory. This paper proposes a sensorless predictive current controller to enhance power factor (PF) of LED lamp driver and reduce driver cost. The inductor current is estimated instead of employing current sensor relying on measured input and output voltages. Zero-crossing detector is utilized to accomplish robust performance during distorted supply voltage. The controller and power circuit are isolated. The control algorithm employs a two-loop control to achieve a high PF with sinusoidal input current. Rapid speed performance is accomplished. The influences of PFC on input current value, PF and harmonic orders are presented. A prototype LED lamp driver with the suggested PFC structure is tested practically by a digital signal processor (DSP) DS1104 platform to validate its effectiveness. Experimental tests under various working conditions are provided to prove the usefulness of the suggested PFC control.
Implementation of Close Loop Speed Control with VVVF Control and Slip Regulation on LIM
Authors: Aditya K. , Newwel A.
Published: November 2020

Open loop VVVF control has the disadvantage of low output torque when working at low frequency and poor speed precision at different load conditions.Various performance-improving schemes have been proposed for the basic VVVF control by compensating slips occurring in the low frequency range and slips caused by changing loads. Numerous papers have been published on the close loop speed control of rotary induction motor. In this paper a close loop speed control with VVVF control and slip regulation has been implemented for LIM based conveyor belt test Rig which compensates the disadvantages of traditional Volts/Hz control. SIMULINK results are presented to validate the effectiveness of proposed scheme.
Dynamic Matrix Control and Tuning Parameters Analysis for a DC Motor System Control
Authors: Ndje M. , Nyobe Yome J. M. , Boum A. T. , Bitjoka L. , Kamgang J. C.
Published: November 2020

Model predictive control (MPC) in system control industry overrides the challenges of conventional controllers in controlling complex systems. However, for efficient control, it is essential to find the best combination of parameter values. In this paper, we present the implementation of a multivariable dynamic matrix control (DMC) algorithm. An industrial system consisting of a DC motor, coupled to a mechanical load, the assembly associated with an electronic speed variator was considered to test the implemented DMC controller. DMC’s tuning parameter analysis on the manipulated inputs and their variations on the controlled outputs was performed. Results guarantee that efficient control was presented.
Optimal Allocation of DSTATCOM in Distribution Network Using Whale Optimization Algorithm
Authors: Balamurugan P. , Yuvaraj T. , Muthukannan P.
Published: November 2020

This paper deals with a new approach implemented to decrease power losses and improve voltage profile in distribution networks using Distribution STATic COMpensator (DSTATCOM). DSTATCOM location can be determined by the voltage stability index (VSI) and sizing can be identified by nature inspired, recently developed whale optimization algorithm (WOA). To check efficacy, the proposed technique is tested on two standard buses: Indian rural electrification 28-bus and IEEE 69-bus distribution systems. Obtained results show that optimal allocation of DSTATCOM effectively reduces power losses and improves voltage profile.
A Novel DTC Method with Efficiency Improvement of IM for EV Applications
Authors: Aygun H. , Aktas M.
Published: November 2020

Induction motor (IM) stator flux optimization is very important in order to get increasing running distance per battery charge of electric vehicles (EVs). This study introduces a new direct torque control (DTC) method for efficiency improvement of IM in EV applications. Also, it is proposed to decrease the torque ripple of DTC based IM. Generally, loss minimization algorithms can be simplified by neglecting the core loss or the effect of leakage inductance in the motor model. However, neglecting the core loss causes an error in torque control of DTC. Beside this, exact loss minimization cannot be achieved since a large voltage drop across leakage inductance occurs especially in high-speed region. In the proposed method, the motor model is simplified by neglecting the current in the core loss resistance branch instead of neglecting the core loss and the effect of leakage inductance. The proposed method is simulated in Matlab for variable speeds and loads. Results show that it provides a significant reduction of losses and decreases the torque ripple of IM drives.
Improving Performance of the Braking Process, and Analysis Torque-Speed Characteristics of the Induction Motor
Authors: Al-Barbarawi O. M.
Published: November 2020

This study aims to investigate, analyze, discuss and illustrate an effective and reliable fast braking system used in a three-phase induction motor by combining two or more different conventional braking methods such as dynamic-plugging and electromagnetic-plugging. The plugging process is implemented by disconnecting one of the stator phases and connecting it with an electromagnetic brake while interchanging the other two phases. The dynamic process is executed by inserting high resistance in the rotor circuit of the motor. The performance of the torque-speed characteristics of the induction motor will be studied and analyzed through the dynamic process. Mathematical models have been developed and simulated. Results show that the braking process time is greatly reduced.
Implementation of an Optimized Steganography Technique over TCP/IP and Tests Against Well-Known Security Equipment
Authors: Tarhda M. , Gouri R. E. , Hlou L.
Published: November 2020

Nowadays we are witnessing a total convergence towards a digital world where information is digitized, conveyed and processed using highly developed techniques and tools. The development of broadband networks, including the internet, has made easy the manipulation, transmission and sharing of information. However, new security issues arise and they are particularly related to integrity, confidentiality and traceability of data. Facing this situation, network security has become very important and challenges related to the protection of exchanged data over the internet against unauthorized access and use have increased. In the current work, we propose to implement an optimized steganography technique over TCP/IP protocol [1]. We have also tested it against well-known security equipment using latest versions. We will see that they are inefficient to stop this kind of cover channels. Our work is like an alarm to every IT administrator to change their thinking about data lost prevention (DLP) and exfiltration of sensitive information.
A Comparative Study of Construction Waste Generation Rate Based on Different Construction Methods on Construction Project in Malaysia
Authors: Maniam H. , Nagapan S. , Abdullah A. H. , Subramaniam S. , Sohu S.
Published: November 2020

High construction waste (CW) generation in Malaysia has serious impacts although there are very little available data regarding the relevant issue in Malaysia. This lack of data results in improper CW management and CW disposal without proper control measures. To control the implications of CW, it is very important to understand their quantity which is currently unknown. Past researches in Malaysia, found that CW generation was affected by construction methods (CMs) practiced on site. The aim of this study is to compare the CW generation rate between different CMs for on-going construction projects in Malaysia. Common CMs practiced in Malaysia are conventional construction method (CCM), mixed construction method (MCM) and industrialized building system (IBS). To obtain CW generation data, site visit (SV) method, which consists of direct measurement (DM) and indirect measurement (IM) is applied to this study. CCM was recorded to have the highest amount of waste (197.657 tons). IBS method records 77.188 tons and MCM 53.191 tons. Regarding the average waste generation rate (AWGR), IBS recorded a value of 0.018 tons per square meter, while MCM recorded 0.030 tons per square meter and CCM recorded the highest amount of 0.046 tons per square meter.
Assessment of Wind Power Potential Based on Raleigh Distribution Model: An Experimental Investigation for Coastal Zone
Authors: Memon B. , Baloch M. H. , Memon A. H. , Qazi S. H. , Haider R. , Ishak D.
Published: November 2020

When compared with other renewable energy resources (RER), the wind energy share in the global energy production is increasing rapidly. Currently, the Government of Pakistan (GoP) is moving towards RER, specifically wind and solar energy. In this paper, the wind energy potential of Tando Ghulam Ali, Sindh, Pakistan is explored. For this purpose, one-year wind speed data is considered at various heights through various probability distribution functions (PDFs). Statistical comparison of Rayleigh, gamma, generalized extreme value (GEV) and lognormal PDFs have been done with two methods, namely root mean square error and (R^2) in order to select the best PDF. Results showed that the Rayleigh distribution function is the best at the above mentioned area for finding various factors like site selection and wind power cost per kWh.
Electric Ferry Ecosystem for Sustainable Inter-Island Transport in Philippines: A Pilot Study
Authors: Palconit E. V. , Abundo M. L. S.
Published: November 2020

An electric boat system as a pilot study for the electric ferry was designed and field-tested in Samal Island, Philippines, to verify sustainability for inter-island transport. This pilot study uses 4.5m monohull with a displacement weight of 343kg. During the experiment, two cases were compared: in the first case the boat was powered solely with batteries and in the other case with the aid of photovoltaic (PV) modules. For the first case, 24V electric propulsion was driven by two 12V, 100Ah batteries, which resulted to a navigational range of around 18, 16 and 15 trips with energy consumption of 111.64Wh, 117.19Wh and 123.92Wh respectively. In the second case, the photovoltaic modules were attached on the boat to supplement the PV used while on sail. Results in the second case showed that PV module supplemented energy was about to 13.4%, 26.8% and 38.7% using three different speeds like 3.18, 3.32 and 3.84knots and the navigational range extended to 4km, 1km, and 14.4km respectively. Therefore, the electric boat with the aid of PV module answers the problem in the energy management system that deals with the sustainability of the system in the inter-island transport in Philippines.
Preliminary Survey on the Crucial Root Causes of Material Waste Generation in Malaysian Construction Industry
Authors: Nagapan S. , Kaliannan S. , Abdullah A. H. , Sohu S. , Deraman R. , Hasmori M. F. , Abas N. H.
Published: November 2020

Construction waste generation has been perceived as a crucial issue that has critical consequences on the project effectiveness and ecological effect of the construction industry. The key objective of the current research is to identify the root causes of material construction waste generation in Malaysia. A well-structured questionnaire was designed based on the 52 identified root causes of material waste generation. The developed questionnaire was distributed to 35 highly experienced in Malaysian construction industry experts. The collected data was analyzed by the use of mean score analysis. The top identified root causes are poor supervision during the construction stage, lack of efficient site management, last minute changes, cutting uneconomical sizes of materials, and constant design changes during the construction period. The initial findings will aid construction practitioners to focus on these root causes in order to reduce the material construction waste generation at construction sites.
Impact of Hairdin, Miro Khan and Shahdad Kot Drainage on Hamal Dhand, Sindh
Authors: Mahessar A. A. , Qureshi A. L. , Laghari A. N. , Qureshi S. , Shah S. F. , Shaikh F. A.
Published: November 2020

Safe drinking water is a basic need. Surface water bodies are the primary source of safe water. Drain water, industries, urban/rural effluents, and waste materials are often disposed into surface water bodies without any treatment. All major water bodies of Sindh province are thus more or less polluted. These water bodies are interconnected with the Indus River like the artery system for blood circulation in bodies of living things. The main source of contamination of Hamal Lake is the disposal of the effluents of Hairdin drain, Miro Khan drain, and Shahdad Kot drain. This lake’s main source of fresh water is rained from Khirthar mountains. Hamal lake is connected through the Main Nara Valley drain (MNVD) to Manchar lake that eventually outfalls into Indus River. Hence, drain water pollutes not only Hamal and Manchar lakes but also Indus River due to their interconnection. Presently, right bank outfall drains (RBOD I-III) have been constructed for safe disposal of drain effluents thus avoiding the polluting of freshwater bodies.
A Novel Voltage Divider Circuit
Authors: Selvam K. C. , Latha S.
Published: November 2020

A novel analog divider is described in this paper. The circuit enables the division of a dc voltage with another dc voltage. The constant of the division is dependent upon a third dc voltage and a pair of resistors. Employing a precision source for the third dc voltage and matched resistors, an acceptable level of accuracy can be obtained.
Swarm Optimization-Based Modified Selective Harmonic Elimination PWM Technique Application in Symmetrical H-Bridge Type Multilevel Inverters
Authors: Gopal Y. , Panda K. P. , Birla D. , Lalwani M.
Published: November 2020

The problem of elimination of harmonics and the need of a large number of switches in multilevel inverters (MLIs) have been a hot topic of research over the last decades. In this paper, a new variant swarm optimization (SO) based selective harmonic elimination (SHE) technique is described to minimize harmonics in MLIs, which is a complex optimization problem involving non-linear transcendental equation. Optimum switching angles are calculated by the proposed algorithms considering minimum total harmonic distortion (THD) and the best results are taken for controlling the operation of MLIs. The performance of the proposed algorithm is compared with the genetic algorithm (GA). Conventional MLIs have some disadvantages such as the requirement of a large number of circuit components, complex control, and voltage balancing problems. A novel seven-level reduced switch multilevel inverter (RS MLI) is proposed in this paper to recoup the need of a large number of switches. Matlab/Simulink software is used for the simulation of two symmetrical topologies, i.e., a seven-level cascaded H-bridge multilevel inverter (CHB MLI) and a seven-level (RS MLI). Simulation results are validated by developing a prototype of both MLIs. The enhancement of the output voltage waveform confirms the effectiveness of the proposed SO SHE approach.
Wavelet Based Simulation and Analysis of Single and Multiple Power Quality Disturbances
Authors: Jandan F. , Khokhar S. , Memon Z. A. , Shah S. A. A.
Published: November 2020

Improving power quality disturbance (PQD) detection and automatic classification has been a major concern ever since the emergence of sensitive non-linear devices. The role of distributed generation in a power system is the main source of PQDs. Short-term and long-term duration single and multiple complex PQDs are difficult to monitor and need higher accuracy and time. This paper presents the analysis of different and distinctive combinations of PQDs. Variety of single and multiple PQD samples are generated using Matlab environment conferring to IEEE STD 1159-2009. Such disturbance samples are accurately detected and analyzed from waveform patterns using multi resolution analysis based discrete wavelet transform. The generation of samples and detection lies in fact that it can allow the feature extraction process for the training/testing sample features for machine learning based automatic recognition of disturbance types.
Investigation of Quantity, Quality and Energy Content of Indigenous Sugarcane Trash in Naoshehro Feroze District, Sindh
Authors: Solangi S. H. , Jakhrani A. Q. , Mukwana K. C. , Jatoi A. R. , Luhur M. R.
Published: November 2020

Quantity, characteristics, and energy content in sugarcane trash of six different indigenous sugarcane varieties were computed for their possible utilization. Results revealed that the total sugarcane trash weight percentage was 24.0% of the total sugarcane crop. Among all examined varieties, variety 240 produced the highest and the variety HS12 the lowest percentage of sugarcane trash with 28% and 18.6% respectively. Moisture and ash content were found less in brown leaves and more in the tops of sugarcane trash parts. The fixed carbon values in brown leaves, green leaves, and tops of the variety Thatta10 were the highest found, with 18.4%, 15.5%, and 17.3% respectively. Carbon element’s percentage in brown leaves of variety HS12 was the highest with 50.0% and in Thatta10 was the lowest with 43.4%. Highest heating value was found in Thatta10 with 16.0MJ/kg, which is close to the literature reported values.
An Experimental Study on Boron Carbide Reinforced Open Cell Aluminum Foams Produced via Infiltration Technique
Authors: Sunar T. , Cetin M.
Published: November 2020

Light structures and parts are very effective for new engineering applications. Their considerably low densities, high energy absorption capabilities, and desirable mechanical properties make them useful for particularly automotive, defense and aerospace industries. Besides these positive properties, it is known that the production and processing of cellular materials is very tough and worth the effort. Recently, with advances in new technologies like 3D printing or selective laser melting, now different types of cellular materials can be produced. But manufacturing of metallic foams via casting especially replication or infiltration method is fairly an economic method when compared with other methods. In this study, vacuum-gas infiltration set-up was used to produce B4C reinforced aluminum foams. The mentioned method involves the addition of space holder materials and a dissolution technique to remove them after solidification of the metal. As space holder materials NaCl particles were selected and mixed with B4C powders to produce B4C reinforced A360 aluminum foam. By changing the weight ratio of B4C particles, the alteration of properties like porosity, compression strength, and energy absorption capacity was investigated. Additionally, computer tomography views were obtained to see and interpret the microstructures of the foams. Compression tests were carried out to evaluate the mechanical behavior of the foams under static loading. The porosities of samples obtained as between 65-75%. The compressive strength increased with rising relative density.
Electrocardiogram (ECG) Signal Modeling and Noise Reduction Using Hopfield Neural Networks
Authors: Bagheri F. , Ghafarnia N. , Bahrami F.
Published: November 2020

The Electrocardiogram (ECG) signal is one of the diagnosing approaches to detect heart disease. In this study the Hopfield Neural Network (HNN) is applied and proposed for ECG signal modeling and noise reduction. The Hopfield Neural Network (HNN) is a recurrent neural network that stores the information in a dynamic stable pattern. This algorithm retrieves a pattern stored in memory in response to the presentation of an incomplete or noisy version of that pattern. Computer simulation results show that this method can successfully model the ECG signal and remove high-frequency noise.
Systems Modeling Using Deep Elman Neural Network
Authors: Belhaj Salah L. , Fourati F.
Published: November 2020

In this paper, the modeling of complex systems using deep Elman neural network architecture is improved. The emphasis is to retrieve better deep Elman structure that emulates perfectly such dynamic systems. To achieve this goal, sigmoid activation functions in the hidden and output layers nodes are chosen and data files on considered systems for modeling and validation steps are given. Simulation results prove the ability and the efficiency of a deep Elman neural network with two hidden layers in this task.
Investigation of Mechanical Properties of Shale Rock in Qassim Region, Saudi Arabia
Authors: Irfan M. Α. , Almufadi F. A.
Published: November 2020

An investigation into the mechanical properties of shale rock from Qassim Province, Saudi Arabia is presented in this paper. Uniaxial compression test, Schmidt hammer test and porosity estimation were carried out. Regarding the compression test, it was found that the strength ranged from 1.98MPa to 8MPa and the strain ranged from 0.53% to 2.5%. Regarding the Schmidt Hammer test, it was found that the rebound values ranged from 22.4 to 25. The measurements of volumetric porosity indicated that the porosity in the shale rock ranged between 19.12% and 24.31%. All the values determined in this project match well with the published values of other studies about shale rock.
Energy Cycle Optimization of Mobile Phones Using A Sleep Cycle Optimization Algorithm
Authors: Murawwat S. , Manzoor I. , Akash H. , Ahmed J.
Published: November 2020

Researchers and mobile network operators are dealing with the steep rise in energy consumption of mobile phones. A massive amount of phones are available in the market which are updating services from time to time. The problem lies in their battery drainage in response to the usage of internet-based applications including online streaming, multimedia requests, social networking usage and many more. In this research, a new technique is proposed and evaluated for energy optimization in mobile phones by exploiting the listening cycle of the mobile station (MS) wake-up mode while connected to the base station (BS) that is connected to a mobile network based on IEEE 802.16e. An MS cannot communicate with the BS if it is in the sleep mode while the other is in the wake-up mode. Service time and sojourn time are assumed to be exponential and based on t-distribution. The confidence interval comes up to 95% for our technique. The relative error is computed between the earlier techniques available and the approximated proposed one. Results show that there is a considerable improvement in energy consumption as compared to the other available techniques.
Effect of Water-Cement Ratio on Flexural Strength of RC Beams Made with Partial Replacement of Coarse Aggregates with Coarse Aggregates from Old Concrete
Authors: Oad M. , Buller A. H. , Memon B. A. , Memon N. A. , Tunio Z. A. , Memon M. A.
Published: November 2020

This research paper presents an experimental evaluation of the effect of water-cement ratio on the flexural strength of reinforced concrete beams made with 50% replacement of coarse aggregates with recycled concrete aggregates (RCA). 72 reinforced concrete beams were cast using 0.54, 0.6, 0.65 and 0.70 water-cement ratio. In each ratio, 12 beams were cast using RCA and 3 beams were cast using all-natural coarse aggregates (NCA). Beams were cured for 7 and 28 days. After curing, all beams were tested with central point load in a universal load testing machine. From the obtained results, it is observed that the maximum reduction in flexural strength of RCA beams is about 28% when compared to the 0.54 w/c ratio beams of the same group and 31.75% in comparison to NCA beams cast with same w/c ratio. The maximum deflection and average strain in beams remained within limits. The observed cracking pattern shows shear failure of all beams.
Performance of Steel Frame with Linkage System under Earthquake Excitation
Authors: Xu G. , Yamanari M.
Published: November 2020

Authors have already proposed a linkage system with rotational friction dampers that can be expected to dissipate seismic energy rather than the main frame. In this paper, the relationship between the rotational angle of the linkage system and inter-story drift angle of a structure was investigated. Consequently, a three-bay twelve-story steel frame with linkage system was analyzed by a numerical simulation program based on a theory of non-linear dynamic analysis. The distribution of slipping moment of friction damper along with the height of the main structure was discussed. Meanwhile, optimal slipping moment range was suggested according to analysis results.
An Efficient and Highly Secure Technique to Encrypt and Decrypt Color Images
Authors: Al-Dwairi M. O. , Hendi A. Y. , AlQadi Z. A.
Published: November 2020

Digital color images are considered as the most widely used data. They are exchanged frequently on the internet and via email, so an efficient and highly secure method of color image encryption and decryption is needed. Different methods of encryption-decryption are used, but most of them suffer from low efficiency or low-security level or both. In this paper, an efficient and highly secure method of encryption-decryption will be proposed, tested, and implemented. The efficiency parameters will be calculated and compared with other methods’ parameters to prove the efficiency of the proposed method.
Identification, Assessment and Mitigation of Environment Side Risks for Malaysian Manufacturing
Authors: Shahbaz M. S. , Kazi A. G. , Othman B. , Javaid M. , Hussain K. , Rasi R. Z. R. M.
Published: November 2020

Malaysia has faced many supply chain issues that not only have affected enterprises but also the overall economy. Natural disasters that badly affect the performance of Malaysian enterprises strongly demand a comprehensive investigation of supply chain risks. Effective mitigation strategy can only be operationalized when risks are appropriately identified and assessed. Supply chain collaboration has been verified to have a positive impact on the performance but only a limited number of studies investigate it as a risk mitigation tool. The current study presents a guiding framework for identification, assessment, and migration of environment side risks for Malaysian manufacturing. A questionnaire has been developed and distributed by systemic probability sampling. Data have been collected from the Federation of Manufacturing Malaysia through an online survey. The data were purified from missing values and outliers and were analyzed through structural equational modeling through Smart PLS. A total of nine environment side risks were identified. In risk assessment, it has been found that an environment side risk has negative effects on supply chain performance. While these risks can be mitigated through supply chain collaboration, they cannot be mitigated completely. This study will help managers to understand how environment side risks are affecting enterprise performance and how they can avoid these risks. This study covers only environment side risks while future research can be on operational risks and various other approaches that can be proposed for mitigation.
Study on the Removal of Thiosulfate from Wastewater by Catalytic Oxidation
Authors: Al-Khazaal A. Z. , Ahmad F. , Ahmad N.
Published: November 2020

Wastewater streaming from industrial plants, including petroleum refineries, chemical plants, pulp and paper plants, mining operations, electroplating operations, and food processing plants, can contain offensive substances such as cyanide, sulfides, sulfites, thiosulfates, mercaptans and disulfides that tend to increase the chemical oxygen demand (COD) of the streams. In the present work, removal of thiosulfate from wastewater by catalytic oxidation using aluminum oxide as a catalyst was studied. Four main factors were considered, namely the initial thiosulfate concentration, the hydrogen peroxide concentrations, the amount of the catalyst and the operating temperatures. The analysis of thiosulfate and sulfate was carried out by using UV Visible Spectrophotometer. An empirical rate equation was developed.
An Efficient Algorithm Proposed For Smoke Detection in Video Using Hybrid Feature Selection Techniques
Authors: Matlani P. , Shrivastava M.
Published: November 2020

As an emerging development in the digital technology era, video processing is useful in a wide range of applications. In the current paper, an algorithm is proposed which is useful for smoke detection in video processing. The algorithm quickly detects fire by eliminating common interruptions like noise, overlapping due to the collision, etc. The proposed algorithm is composed of several techniques such as Haar feature, Bhattacharya distance method, SIFT descriptors, Gabor wavelets approach and SVM classifier to identify the smoke by video processing. Foreground object is identified using a moving object algorithm by predicting the movement of smoke in stable images. The implementation has been carried out in MATLAB.
Design and Test of a New Three-Phase Multilevel Inverter for PV System Applications
Authors: Nouaiti A. , Saad A. , Mesbahi A. , Khafallah M. , Reddak M.
Published: November 2020

This paper presents a test of a new three-phase multilevel inverter for PV system applications with reduced number of used DC sources and power switches. The topology of the inverter is designed using an electric assemblage of a two-level dc-dc boost converter (TLBC) with a simplified three-phase multilevel DC-AC converter (THPMC). The TLBC generates two balanced output DC voltages, while the THPMC converts these two DC voltages and generates three-phase AC voltages with five levels per line. Two modulation control techniques are used and tested with the proposed PV system on PSIM and on ISIS Proteus software. The achieved results prove the simplicity and efficiency of the proposed three-phase inverter.
Identifying Motivational and Demotivational Productivity Factors in Qatar Construction Projects
Authors: Momade M. H. , Hainin M. R.
Published: November 2020

Motivation is one of the factors that influence productivity. Project management plays a vital role in the success of projects in Qatar construction industry (QCI). It relies profoundly on the team’s active participation and effective performance. Hence it is important to assess the impact of motivation and demotivation on performance. The main objective of this paper is to identify the key factors that cause motivation and de-motivation in QCI. Literature review, surveys with experts and semi-structured interviews were conducted to identify these factors. Using these factors to conduct specific motivational programs will help improve productivity in QCI. Research on motivational factors impacting productivity has not been conducted in Qatar before, so this work will provide insight on how to deal with productivity issues that QCI faces ahead of a major world event that Qatar will host in 2022.
Shrinkage of Concrete Panels Made with Recyclable Concrete Aggregates
Authors: Soomro F. A. , Memon B. A. , Oad M. , Buller A. H. , Tunio Z. A.
Published: November 2020

An experimental study on the shrinkage of recyclable aggregate concrete panels is presented in this paper. Recyclable aggregates are used in 50%, 60%, 70% and 80% replacement of natural coarse aggregates. For each replacement percentage, 3 panels were cast using 1:2:4 mix with 0.54 water-cement ratio and were cured for 28 days. In addition, 3 panels with the same parameters but using all-natural coarse aggregates were also cast to compare the results. Shrinkage in all panels was recorded for 3 months. Comparison of results reveals that with a 50% replacement, 8.33% increase in shrinkage was recorded. Along with shrinkage, cracks were also observed. At the end of the three month period, the widest crack had less width than 1mm, showing good resistance of the proposed material to shrinkage. Concluding, 50% replacement can be used in new concrete.
Free Convection MHD Couette Flow with Application of Periodic Temperature and Constant Heat Flux on Walls
Authors: Abdullah M. R. , Saada N.
Published: November 2020

Numerical analysis and analytical solution were performed to study the free convection in transient Couette flow of an electrically conducting fluid confined between two vertical parallel plates. Constant heat flux on the wall with uniform vertical motion in its own plane and periodic temperature on the stationary wall were applied. The dimensionless governing momentum and energy equations are solved numerically using a fully implicit finite difference method. An analytical solution using eigenfunction expansion method is carried out for temperature profile in case of constant plate temperature. Analytical and numerical results converge at a satisfactory degree. The effect of different physical parameters on the transient velocity and temperature, such as Grashof’s number (Gr), magnetic parameter (M), Prandtl number (Pr) and temperature frequency are also studied. It is found that the velocity increases with an increase in Gr and temperature frequency, while it decreases with an increase in Pr and M.
Green Scenarios for Power Generation in Vietnam by 2030
Authors: Nguyen V. H. M. , Nguyen L. D. L. , Vo C. V. , Phan B. T. T.
Published: November 2020

Energy for future sustainable economic development is considered one crucial issue in Vietnam. This article aims to investigate green scenarios for power generation in Vietnam by 2030. Four scenarios named as business as usual (BAU), low green (LG), high green (HG) and crisis have been proposed for power generation in Vietnam with projection to 2030. Three key factors have been selected for these scenarios, namely: (1) future fuel prices, (2) reduction of load demand caused by the penetration of LED technology and rooftop photovoltaic (PV) systems, and (3) the introduction of power generation from renewable sources. The least costly structure of power generation system has been found. CO2 emission reduction of HG in comparison to the BAU scenario and its effect on generation cost reduction are computed. Results show that BAU is the worst scenario in terms of CO2 emissions because of the higher proportion of power generation from coal and fossil fuels. LG and HG scenarios show their positive impacts both on CO2 emissions and cost reduction. HG is defined as the greenest scenario by its maximum potential on CO2 emission reduction (~146.92Mt CO2) in 2030. Additionally, selling mitigated CO2can make green scenarios more competitive to BAU and Crisis in terms of cost. Two ranges of generation cost (4.3-5.5 and 6.0-7.7US$cent/kWh) have been calculated and released in correspondence with low and high fuel price scenarios in the future. Using LED lamps and increasing the installed capacity of rooftop PVs may help reduce electric load demand. Along with the high contribution of renewable sources will make the HG scenario become more attractive both in environmental and economic aspects when the Crisis scenario comes. Generation costs of all scenarios shall become cheap enough for promoting economic development in Vietnam by 2030.
Three-Point Bending Response of Corrugated Core Metallic Sandwich Panels Having Different Core Configurations – An Experimental Study
Authors: Zurnaci E. , Gokkaya H. , Nalbant M. , Sur G.
Published: November 2020

Bending response of corrugated core metallic sandwich panels was studied experimentally under three-point bending loading. Two different core configurations were used: the corrugated monolithic core and the corrugated sliced core. The trapezoidal corrugated cores were manufactured from aluminum sheets via a sheet metal bending mould. After the sandwich panel samples were prepared, they were subjected to three-point bending tests. The load and displacement responses of the sandwich panels having different core configurations were obtained from the experimental testing. The influence of the core configuration on the three-point bending response and failure modes was then investigated. The experimental results revealed that the corrugated sliced core configuration exhibited an improved bending performance compared to the corrugated monolithic core configuration.
Design and Modeling of a Radiofrequency Coil Derived from a Helmholtz Structure
Authors: Ghaly S. M. A. , Al-Snaie K. A. , Ali A. M.
Published: November 2020

This paper focuses on radiofrequency (RF) coils that can produce a high electromagnetic field homogeneity to be used for magnetic resonance imaging (MRI) applications. The proposed structure is composed of four wire loops symmetrically located on an ellipsoidal surface. The main objective of this work is to improve field homogeneity compared to a standard Helmholtz coil. Numerical simulation was carried out to assess the RF electromagnetic field behavior of the proposed coil. Different electrical modeling and simulations were investigated, particularly the study of the whole modeling of the proposed structure taking into account all the couplings between the loops. The proposed coil was evaluated and compared with the standard Helmholtz coil. Simulation and experimental results confirmed the good performance of the developed coil in terms of electromagnetic field homogeneity, efficiency, sensitivity, and quality factor.
Limits of Number of Motes at Smart City Scenarios for LoRaWAN
Authors: Catak M. , Celikkaya B.
Published: November 2020

LoRaWAN is an emerging technology as a solution to IoT sensor networks. Since it is still in the evolvement stage, academic and industrial researches and applications have to be conducted in order to analyze its limitations and possible improvements. In this paper, the number of motes that could transmit data to a gateway within a 95% confidence interval has been studied under a number of scenarios. According to the results, the most significant parameter regarding the number of motes is the period of the downlink signal.
Marble Powder As Fine Aggregates in Concrete
Authors: Memon M. J. , Jhatial A. A. , Rid Z. A. , Rind T. A. , Sandhu A. R.
Published: November 2020

Marble industry contributes significantly to the socio-economic development of any country. Due to the abundance of marble reserves, Pakistan relies on marble industry, which in turn contributes to its GDP. Marble powder (MP), produced from the marble industry is also increasing, which constantly remains a source of hazards to the environment. At the same time, natural sand deposits are decreasing, causing an acute need for a product that matches the properties of sand in concrete. This study has been conducted to demonstrate the possibility of using MP as a replacement of sand in the manufacturing of concrete. The MP was used in 5 different dosage percentages ranging from 0% to 100% by weight of sand with an increment of 25%. The effect of MP on the strength behavior of concrete was studied at three different curing ages (7, 14 and 28 days). It was observed from the results that MP could potentially replace sand up to a certain limit without compromising on strength. It was also noticed that 50% sand replacement with MP was optimum at which 13.52% and 35.54% increase in compressive and flexural strength was achieved compared to the control sample. Based on the results of this experimental study, it is clear that MP can partially be used in place of sand in concrete.
Development of Vinyl Ester and Reed Composite Material with Weight Fraction of 10% and Reinforcement at Different Orientations
Authors: Kazi Q. A. , Jamali Q. B. , Bhatti M. T. , Rajput U. A. , Kazi I. A. , Solangi S. H.
Published: November 2020

Composite materials have been used to resolve industrial problems. Considerable attention from the industrial side started in the 1960s with the introduction of polymer-based composite materials. Their advantages such as low weight (density), resistance to corrosion, high strength and low maintenance cost made composite materials an attractive substitute to conventional materials. A new composite material was developed with 10% natural fiber at 0o, 90o and 0/90o orientations resulting in ample improvements in the mechanical properties as compared to previous studies. The sample at 0/90o orientation gives the best results with tensile, tensile strength, tensile elongation and Young's Modulus values of 2458.19N, 4594.5MPA, 4.7% and 23.0 respectively
Advantages of Giraph over Hadoop in Graph Processing
Authors: Vidal-Silva C. L. , Madariaga E. , Pham T. , Rubio J. M. , Urzua L. A. , Carter L. , Johnson F.
Published: November 2020

This article presents a comparison of the computing performance of the MapReduce tool Hadoop and Giraph on large-scale graphs. The main ideas of MapReduce and bulk synchronous parallel (BSP) are reviewed as big data computing approaches to highlight their applicability in large-scale graph processing. This paper reviews the execution performance of Hadoop and Giraph on the PageRank algorithm to classify web pages according to their relevance, and on a few other algorithms to find the minimum spanning tree in a graph with the primary goal of finding the most efficient computing approach to work on large-scale graphs. Experimental results show that the use of Giraph for processing large-size graphs reduces the execution time by 25% in comparison with the results obtained using the Hadoop for the same experiments. Giraph represents the optimal option thanks to its in-memory computing approach that avoids secondary memory direct interaction.
Optimization of Air Distribution in a Baghouse Filter Using Computational Fluid Dynamics
Authors: Lima W. F. , Huebner R.
Published: November 2020

Baghouse filters are used to reduce the emission of pollutants in the atmosphere. With the stricter environmental regulations and the need to avoid the emission of pollutants into the atmosphere, the demand for better results in terms of collection efficiency and filtration rises. A good performance of a baghouse filter is closely linked to the correct flow distribution inside it, whether in the hopper or in the bags. Other important variables for good performance are internal speed, filtration rate (RAP), pressure drop, cleaning efficiency, etc. The upgrading of existing bag filters to current standards is a major challenge for the industry, generally due to, among other factors, emission regulations and common physical and dimensional constraints of the existing equipment. Computational Fluid Dynamics analysis (CFD) can help deal with this problem because it makes possible to perform several analyzes at a lower cost and with great result accuracy when compared with the traditional approaches. In this work, the analysis of an existing bag filter, which presents serious problems of premature discharging of components due to nonuniformity in the internal distribution of the flow, is performed. This analysis has several steps, among them, documentation survey, field survey, flow and pressure drop measurements (pressure differential between the clean side and the dirty side of the filter) with the aid of CFD, with the objective to raise pressure and velocity and to identify possible dimensional changes to improve flow uniformity.
Flexural Behavior of Reinforced RAC Beams Exposed to 1000°C Fire for 18 Hours
Authors: Buller A. H. , Oad M. , Memon B. A.
Published: November 2020

In order to meet the socio-economic demands around the globe, construction industry not only consumes concrete at a very fast pace but also yields huge amounts of construction and demolishing waste. The phenomenon gives rise to environmental issues due to production of concrete ingredients and due to dumping of the waste. Therefore, one of the solutions is the production of green concrete utilizing demolished waste. This research work studies the effect of prolonged fire (18 hours) on the flexural behavior of reinforced concrete–recycled aggregate beams. The beams were using 50% replacement of natural coarse aggregates with demolished concrete. The beam samples were cast as both normal and rich mix concrete and were cured for 28 days. After curing, the beams were exposed to fire at 1000°C in a purpose made oven, followed by testing in a universal load testing machine under central point load. The test results show that the proposed beams (cast with rich mix) exhibited about 22% reduction in flexural strength. The failure mode of the beams was observed as shear failure.
Influences of Project Management Capabilities on the Organizational Performance of the Saudi Construction Industry
Authors: Sulieman H. A. , Alfaraidy F. A.
Published: November 2020

This paper aims to study the relations between construction enterprises’ project management capabilities and organizational performance. A questionnaire survey was administered to 89 Saudi construction contracting organization administrative members. Data were obtained from 32 projects that were held during the last two years and were analyzed using structural equation modeling (SEM). It was hypothesized in this study that a construction organizational performance is influenced by project management capabilities within the enterprise. A structural equation model was set up to measure the above two latent variables through their constituent variables. This study introduced a method to measure performance both in qualitative and quantitative terms. The strong path coefficients between the constructs of the model are an indication that after decades in pursuit of finding ways to improve the performance of construction organizations, subjective dimensions of performance have proven to be as effective as the traditional objective dimensions.
Lightweight Dynamic Crypto Algorithm for Next Internet Generation
Authors: Al-Omari A. H.
Published: November 2020

Modern applications, especially real time applications, are hungry for high-speed end-to-end transmission which usually conflicts with the necessary requirements of confidential and secure transmission. In this work, a relatively fast, lightweight and attack-resistant crypto algorithm is proposed. The algorithm is a symmetric block cipher that uses a secure pre-shared secret as the first step. Then, a dynamic length key is generated and inserted inside the cipher text. Upon receiving the cipher text, the receiver extracts the key from the received cipher text to decrypt the message. In this algorithm, ciphering and deciphering are mainly based on simple XoR operations followed by substitutions and transpositions in order to add more confusion and diffusion to the algorithm. Experimental results show faster encryption/decryption time when compared to known encryption standards.