bluuebunny/crossref_metadata_2025 huggingface dataset:
Propagation of Electrical Trees under the Influence of Mechanical Stresses: A Short Review
Authors: Danikas M. , Papadopoulos D. , Morsalin S.
Published: November 2020

The present paper deals with the phenomenon of electrical treeing in solid insulation, under the influence of mechanical stresses. In this short review, it is indicated that mechanical stressing can affect the propagation of electrical trees and –depending on whether it is tensile or compressive- it can facilitate (or render more difficult) the breakdown. In aged insulating materials, electrical trees can appear very quickly and can lead to breakdown.
Impact of Long-Term Loading on Reinforced Concrete Beams Made with Partial Replacement of Coarse Aggregates with Recycled Aggregates from Old Concrete
Authors: Oad M. , Buller A. H. , Memon B. A. , Memon N. A.
Published: November 2020

This research work presents an experimental evaluation of the effect of sustained loading on reinforced concrete beams made with 50% replacement of natural coarse aggregates with aggregates from old concrete. A total of 9 RC beams were cast, 6 with natural coarse aggregates and 3 with recycled concrete aggregates. All beams were cured for 28 days in standard fashion. Among the first batch, 3 beams were used to test under short term loading till failure. An application of 50% of short-term loading followed on all beams assembled on purpose made frames. All beams were monitored for deflection, strain, and cracking. Both deflection and strain remained within limits. Crack monitoring revealed maximum crack width 0.5 mm. After six months of sustained load, beams were removed from the frames and tested in universal load testing machine with central point load till failure. The load-deflection pattern of all beams was observed to be almost similar and 22.12% higher in recycled concrete beams than all-natural aggregate beams. The results show promising use of recycled concrete aggregates in new concrete subjected to sustained loading.
Composite Feature Extraction and Classification for Fusion of Palm-Print and Iris Biometric Traits
Authors: Alsubari A. , Hannan S. A. , Alzahrani M. , Ramteke R. J.
Published: November 2020

Palm-print and iris biometric traits fusion are implemented in this paper. The region of interest (ROI) of a palm is extracted by using the valley detection algorithm and the ROI of an iris is extracted based on the neighbor-pixels value algorithm (NPVA). Statistical local binary pattern (SLBP) is applied to extract the local features of palm and iris. For enhancing the palm features, a combination of histogram of oriented gradient (HOG) and discrete cosine transform (DCT) is applied. Gabor-Zernike moment is used to extract the iris features. This experimentation was carried out in two modes: verification and identification. The Euclidean distance is used in the verification system. In the identification system, the fuzzy-based classifier was proposed along with built-in classification functions in MATLAB. CASIA datasets of palm and iris were used in this research work. The proposed system accuracy was found to be satisfactory.
Velocity Boundary Layer Analysis of a Flat Plate Heat Exchanger in Laminar Flow: A Case Study
Authors: Mirdrikvand M. , Roozbehani B. , Moqadam S. I. , Roshan A. C. , Ramezani Y.
Published: November 2020

In this article, a behavioral analysis of velocity boundary layer in a flat plate heat exchanger in laminar flow condition through CFD simulation using FLUENT software is done. The main objective of this study is to determine the velocity vectors between the flat plates of the heat exchanger. In addition, wake occurrence, differences of velocity at different surfaces between plates, angles of velocity vectors and the effect of wake phenomenon on the shear stresses exerted on the plates are discussed in detail. The study graphically illustrates results based on fluid’s behavior by a 3D and 2D simulation with air and water as cold and hot streams that affect plate’s situation and its hydro dynamical operations. Consequently, some important design features regarding wake point occurrence and pressure loss are investigated. In addition, eddy current and reverse flows in the wake area and the angles of the velocity vectors are described.
DVR with Modified Y Source Inverter and MCFC
Authors: Chakravorty J. , Sharma G.
Published: November 2020

Power quality is a big challenge nowadays. Various disturbances present in the power system are voltage sag, voltage swell, harmonics, transients, interruptions, voltage collapse etc. To solve the problem of power quality, various custom power devices are generally used in a power system, dynamic voltage restorer (DVR) being one of them. DVR is used for the compensation of voltage sag and swell. In this paper, a model of DVR with molten carbonate fuel cell (MCFC) and Y source inverter is proposed. The proposed model is compared with the existing ones to check its performance characteristics. MATLAB/SIMULINK was been used to check and compare the performance of the proposed with existing models.
Duration Prediction Models for Construction Projects in Middle East
Authors: El-Dash K. M. M. , Ramadan O. M. O. , Youssef W. M. M. A.
Published: November 2020

Construction industry is one of the most influential motivators of a national economy. The success of construction projects is indispensable to sustain a robust economy. Completion time is important for construction projects, nevertheless project multifaceted objectives, sophisticated nature, inherent uncertainties, and risks are success impediments and can cause time overrun. Stochastic models and simulation scheduling techniques are developed to predict the risk and uncertainty effects on construction projects’ duration. The objective of this research is to develop models that predict the activity durations based on actual data from similar projects. The study introduces comprehensive statistical regression models using historical data of about 84,000 activities in Egypt, Kuwait, and Saudi Arabia. The activities encompass engineering, procurement and construction (EPC) activities for most disciplines of construction projects. The regression models can be utilized to predict more reliably the activities’ duration.
A Robust Feature Extraction Method for Real-Time Speech Recognition System on a Raspberry Pi 3 Board
Authors: Mnassri A. , Bennasr M. , Adnane C.
Published: November 2020

The development of a real-time automatic speech recognition system (ASR) better adapted to environmental variabilities, such as noisy surroundings, speaker variations and accents has become a high priority. Robustness is required, and it can be performed at the feature extraction stage which avoids the need for other pre-processing steps. In this paper, a new robust feature extraction method for real-time ASR system is presented. A combination of Mel-frequency cepstral coefficients (MFCC) and discrete wavelet transform (DWT) is proposed. This hybrid system can conserve more extracted speech features which tend to be invariant to noise. The main idea is to extract MFCC features by denoising the obtained coefficients in the wavelet domain by using a median filter (MF). The proposed system has been implemented on Raspberry Pi 3 which is a suitable platform for real-time requirements. The experiments showed a high recognition rate (100%) in clean environment and satisfying results (ranging from 80% to 100%) in noisy environments at different signal to noise ratios (SNRs).
An Experimental Study on the Performance of Calcium Carbonate Extracted from Eggshells as Weighting Agent in Drilling Fluid
Authors: Iqbal R. , Zubair M. , Pirzada F. , Abro F. N. , Ali M. , Valasai A.
Published: November 2020

Drilling mud density is an important factor in drilling operations. The cost of the drilling mud used for oil and gas well drilling can be 10%-15% of the total drilling cost, and the deeper the well, the more the needed drilling mud. This research aims to prepare a mud that provides performance similar to the conventional mud and to lower down the dependency of primitive CaCO3 technology by exploring it from trash/polluted and naturally occurring materials. For that purpose, a mud was prepared by replacing primeval CaCO3 with the CaCO3 derived from eggshells, as eggshells contain CaCO3 in high amounts which range from 70% to 95%. The success of this project will provide an affordable solution and an alternative way to explore new methodologies for obtaining CaCO3. According to the 2017 Report of Pakistan Poultry Association (PPA) 18,000 Million table eggs are consumed per year in Pakistan. The obtained results of this research are quite satisfactory. CaCO3 obtained from eggshells is used in high amounts, 275–410g to achieve density ranges from 9.5 to 11.0 pounds per gallon whereas, pure the needed quantity of pure CaCO3 is 150g to obtain the density of 10.5 pounds per gallon. Apart from this, it is also observed that eggshell based CaCO3 samples are more efficient in rheological properties compared to the market samples of CaCO3 t. The pH of pure CaCO3 sample of 10.5 pounds per gallon density is almost the same with the sample of eggshell CaCO3 of 10.5 pounds per gallon density.
Development of Electronic Water Meter Based on Wireless Network and RF
Authors: Gorenekli K. , Becerikli Y.
Published: November 2020

The global need for water is increasing. Water must be used more economically in order to be sustainable. Water consumption per capita in Turkey is below the world regarding its geographical location. Manual reading water meters are inconvenient and time-consuming, they have low accuracy, they are very slow and resource wasting. Using wireless communication will mitigate these unwanted states. Consumers will be able to observe their water consumption in real time and be able to compare with the average water consumption in their district. With this system water pressure of whole pipes could be observed.
An Intercultural Management Perspective of Foreign Student’s Adaptation in Chinese Universities: A Case Study of China Three Gorges University
Authors: Ping L. , Jing X. , Othman B. , Yuefei F. , Kadir Z. B. A. , Ping X.
Published: November 2020

Globalization, the desire to access quality education and better opportunities abroad as well as the need to develop one’s capacities and many other factors have caused increased migration of international students and teachers into Chinese universities. China has recorded over a 67% increase in higher education enrolment between 2011 and 2017. This increased level of student migration in China has brought an unprecedented number of challenges especially in transitioning into the cultural settings in China. As a result, Chinese universities, in addition to their various obligations and roles in ensuring quality teaching and learning, have to engage in intercultural management to help foreigners’ transition seamlessly into the cultural landscape of China. This study examines intercultural adaptation of sojourners from an intercultural management perspective. Using a mixed method approach, specifically an explanatory mixed method design, a sample of 140 respondents was investigated regarding their cultural adaptation to a Chinese university. The positive and negative aspects of intercultural management as it relates to the university used in the case study were also explored. Findings from the study were discussed in depth and recommendations for a holistic intercultural management system were made.
Mechanical Performance of Honeycomb Sandwich Structures Using Three-Point Bend Test
Authors: Subhani T.
Published: November 2020

In this study, honeycomb sandwich structures were prepared and tested. Facesheets of sandwich structures were manufactured by carbon fiber epoxy matrix composites while Nomex® honeycomb was used as core material. An epoxy-based adhesive film was used to bond the composite facesheets with honeycomb core. Four different curing temperatures ranging from 100oC to 130oC were applied with curing times of 2h and 3h. Three-point bend test was performed to investigate the mechanical performance of honeycomb sandwich structures and thus optimize the curing parameters. It was revealed that the combination of a temperature of 110oC along with a curing time of 2h offered the optimum mechanical performance together with low damage in honeycomb core and facesheets.
Modern Control Laws for an Articulated Robotic Arm: Modeling and Simulation
Authors: Iqbal J.
Published: November 2020

The robotic manipulator has become an integral component of modern industrial automation. The current paper deals with the mathematical modeling and non-linear control of this manipulator. DH-parameters are used to derive kinematic model while the dynamics is based on Euler-Lagrange equation. Two modern control strategies, H∞ and model predictive control (MPC), are investigated to develop the control laws. For an optimal performance, the controllers have been fine-tuned through a simulation conducted in MATLAB/Simulink environment. The designed control laws are subjected to various inputs and tested for effectiveness in transient parameters like settling time and overshoot as well as steady state error. Simulation results confirm the effectiveness of the developed controllers by precisely tracking the reference motion trajectories.
Comparison Between Conditions of Major Roads Within and Outside the Port of Durban
Authors: Kunene O. M. , Allopi D.
Published: November 2020

Over the past years road traffic has increased at the Port of Durban. Due to the lack of maintenance, this has resulted in road deterioration. Roads are considered as the most important transport mode at the Port of Durban. It is an important mean for facilitating economic growth of local, regional and national industries. For the Port to maintain global competitiveness with the current trend of globalization, it has to be ensured that the roads are well maintained. The purpose of the paper is to provide an overview of road condition within and outside the Port. Verification and assessment of the condition of the existing eight major roads was conducted. Comparisons between the condition of the eight major roads within and outside the Port were highlighted.  Conclusions and recommendations were also drawn based on the findings.
Experimental Study on the Impact of Weather Conditions on Wide Code Division Multiple Access Signals in Nigeria
Authors: Eli-Chukwu N. C. , Onoh G. N.
Published: November 2020

In cellular network activities, before a site is integrated it is expected that each cell of the site meets the Nigerian Communication Commission (NCC) standard of ≥98% for both service accessibility and call completion rate which in turn depicts a ≤2% in both blocked call rate (BCR) and dropped call rate (DCR). It is suggested that weather conditions have a very strong negative effect on the performance of wideband code division multiple access (WCDMA) network as it could lead to signal attenuation or change the polarization. In this paper, we study the impact of weather conditions on WCDMA network in Nigeria. To achieve this, network samples (log-files) were collected weekly during a driving test in Enugu State Nigeria for a period of five years for both rainy and dry seasons, in which blocked and dropped calls were extracted. Results show that during adverse weather conditions, BCR and DCR rise greater than 8% and 4% respectively. Although with a slight relationship between the weather conditions, the weather condition during the dry season has a better-blocked call rate of 8.76% in comparison with the rainy season with 12.89%. Calls tend to drop more during the dry season. From the outcome of the experiment, a model was developed for predicting an unknown network call statistics variables.
Distributed File Sharing and Retrieval Model for Cloud Virtual Environment
Authors: Ali M. , Soomro N. Q. , Ali H. , Awan A. , Kirmani M.
Published: November 2020

Cloud-based storage services are multiplying and are being adapted mostly for data storage. At the same time, many potential problems pertaining to data storage and security are being addressed. This research provides the architecture for splitting user data and the solution in retrieving different data chunks, stored on different cloud storages. By doing this, not only the load on a single server is reduced but security and storage are efficiently used. Data would be stored and retrieved in slices, hence the chances of data forgery are diminishing. File processing will be faster as split parts would be fetched from different clouds, enabling parallel processing.
A Satellite-based Remote Sensing Technique for Surface Water Quality Estimation
Authors: Japitana M. V. , Burce M. E. C.
Published: November 2020

Remote sensing provides a synoptic view of the earth surface that can provide spatial and temporal trends necessary for comprehensive water quality (WQ) monitoring and assessment. This study explores the applicability of Landsat 8 and regression analysis in developing models for estimating WQ parameters such as pH, dissolved oxygen (DO), total dissolved solids (TDS), total suspended solids (TSS), biological oxygen demand (BOD), turbidity, and conductivity. The input image was radiometrically-calibrated using fast line-of-sight atmospheric analysis (FLAASH) and then atmospherically corrected to obtain surface reflectance (SR) bands using FLAASH and dark object subtraction (DOS) for comparison. SR bands derived using FLAASH and DOS, water indices, band ratio, and principal component analysis (PCA) images were utilized as input data. Feature vectors were then collected from the input bands and subsequently regressed together with the WQ data. Forward regression results yielded significant high R2 values for all WQ parameters except TSS and conductivity which had only 60.1% and 67.7% respectively. Results also showed that the regression models of pH, BOD, TSS, TDS, DO, and conductivity are highly significant to SR bands derived using DOS. Furthermore, the results of this study showed the promising potential of using RS-based WQ models in performing periodic WQ monitoring and assessment.
Deciding Optimal Location of DPFC in Transmission Line Using Artificial Algae Algorithm
Authors: Chakravorty J. , Saraswat J.
Published: November 2020

In this paper, the application of artificial algae algorithm (AAA) in optimal placement distributed power flow controller (DPFC) with MCFC in transmission networks has been proposed The proposed method is tested on IEEE 14- bus system and the results are discussed. The biggest advantage of DPFC is that it can control the active and reactive power flow and bus voltages, simultaneously. In this paper, the optimal placement of one DPFC in IEEE-14 bus system and then optimal placement of two DPFCs in IEEE-14 bus system has been proposed. Optimal placement of DPFC in power system by AAA leads to increased stability and capacity of the power transmission in lines. The proposed model has been simulated in Matlab/Simulink and the performance results are tabulated.
Optimizing the Production from a Multizone Well by Selecting Appropriate Completion for a Well of Tal Block Pakistan
Authors: Arisar M. R. , Hingoro M. Z. , Abro F. N. , Nawab S. , Hullio I. A.
Published: November 2020

Well completion is the process of construction a well geared up for production or injection. This mainly involves preparing the bottom of the hole to the required conditions, running the production tubing and associated downhole tools. Production from a multizone well can be obtained from a single tubing string as well as from dual tubing strings but it depends on pressure difference, depth and fluid present in the formation. This paper is based on the optimum well completions design for a multizone well of the Tal block region which contains four reservoirs of different formations: Lockhart (limestone), Hangu and Lumshiwal (sandstone), Samanasuk (limestone) & Datta (sandstone) having pressures of 7432psia, 7563psia, 7843psia, and 7982psia respectively. The well is producing four zones (multilayer well) and the generated numerical model for each completion (single string multizone completion and dual string multizone completion) shows better performance and economic feasibility.
A Short Review on Polymer Nanocomposites for Enameled Wires: Possibilities and Perspectives
Authors: Danikas M. , Morsalin S.
Published: November 2020

Polymer nanocomposites constitute a new generation of insulating materials, capable of offering better electrical, thermal and mechanical properties. Past research indicated that such materials may replace conventional polymers for a variety of industrial high voltage applications. In the present paper, polymer nanocomposites are investigated regarding the insulation of enameled wires. Possible nanocomposite candidates are discussed.
Multi-sensor Fusion Workflow for Accurate Classification and Mapping of Sugarcane Crops
Authors: Villareal M. K. , Tongco A. F.
Published: November 2020

This study aims to assess the classification accuracy of a novel mapping workflow for sugarcane crops identification that combines light detection and ranging (LiDAR) point clouds and remotely-sensed orthoimages. The combined input data of plant height LiDAR point clouds and multispectral orthoimages were processed using a technique called object-based image analysis (OBIA). The use of multi-source inputs makes the mapping workflow unique and is expected to yield higher accuracy compared to the existing techniques. The multi-source inputs are passed through five phases: data collection, data fusion, image segmentation, accuracy validation, and mapping. Data regarding sugarcane crops were randomly collected in ten sampling sites in the study area. Five out of the ten sampling sites were designated as training sites and the remaining five as validation sites. Normalized digital surface model (nDSM) was created using the LiDAR data. The nDSM was paired with Orthophoto and segmented for feature extraction in OBIA by developing a rule-set in eCognition software. A rule-set was created to classify and to segment sugarcane using nDSM and Orthophoto from the training and validation area sites. A machine learning algorithm called support vector machine (SVM) was used to classify entities in the image. The SVM was constructed using the nDSM. The height parameter nDSM was applied, and the overall accuracy assessment was 98.74% with Kappa index agreement (KIA) 97.47%, while the overall accuracy assessment of sugarcane in the five validation sites were 94.23%, 80.28%, 94.50%, 93.59%, and 93.22%. The results suggest that the mapping workflow of sugarcane crops employing OBIA, LiDAR data, and Orthoimages is attainable. The techniques and process used in this study are potentially useful for the classification and mapping of sugarcane crops.
Environmental Impact Assessment of the Tidal Link Failure and Sea Intrusion on Ramsar Site No. 1069
Authors: Mahessar A. A. , Laghari A. N. , Qureshi S. , Siming I. A. , Qureshi A. L. , Shaikh F. A.
Published: November 2020

This paper presents the impact on the RAMSAR site No. 1069 that receives fresh water by the Kotri drainage system. At present, the complex faces threats by effluents from the Left Bank Outfall Drain (LBOD) system and from saline seawater intrusion during high tides. These threats have destroyed the ecosystem of the lakes Cholari, Mehro, Pateji and Sanhro belonging to the complex. The total present lake area, maintained at the Cholari weir crest level, is about 170km2. The lakes are expanding, available data shows that there is an increase up to 700% in the original lakes’ area, from 6058 to 41220 acres from 1954 to 1977. This is mainly caused by the operation of Kotri Barrage surface drainage system and has positive impact on lakes’ ecology because the drainage effluent is of marginal salinity. The rapid increase in the lakes’ area, of about 40% within 2 years after the functioning of the Tidal Link with saline effluents from LBOD and sea intruded water have changed the ecology of the area. This posed a significant impact on the ecosystem. Conversely, a similar rise in water level due to sea intrusion has nearly doubled the surface area and reposed a negative impact on the system. These lakes were giving shelter to a wide variety of local and migratory birds and had aquatic biodiversity. Hence, parts of Sanhro and Mehro dhands have been recognized by the RAMSAR Convention
Development and Evaluation of an Isolated Resonant Converter for Auxiliary Power Supply in DC Traction
Authors: Bhajana V. V. S. K. , Drabek P.
Published: November 2020

This paper presents the implementation and evaluation of an isolated resonant converter and also compares the efficiencies of hard and soft switching isolated converter topologies using high-frequency transformer for auxiliary power supplies in DC traction. The half-bridge DC-DC converter with resonant network has been tested under zero voltage switching (ZVS), zero current switching (ZCS) operations, and also dead time variation of the power switches improving the overall system efficiency. This paper provides guidelines for a cost effective DC-DC converter design based on discrete 1200V/40A IGBTs driven with high switching frequency. That would allow optimization of passive elements by reducing their mass making the converter suitable for traction application. Simulations and test results of an experimental setup with output power up to 3kW are presented. The overall system efficiency of the ZVS and ZCS operations of half-bridge LLC DC-DC converter were compared with a classic hard switching topology.
Study of The Phenomena of Surface Discharges and Flashover in Nanocomposite Epoxy Resin under the Influence of Homogeneous Electric Fields
Authors: Danikas M. , Verginadis D. , Sarathi R.
Published: November 2020

A new class of insulating materials is the class of polymer nanocomposites. In the past twenty-five years, a lot of attention was paid to the various electrical, thermal and mechanical properties of polymer nanocomposite materials. In the present work, epoxy resin samples without and with nanoparticles (0 wt%, 1 wt%, 3 wt%, 5 wt%, and 10 wt%) are investigated regarding the surface discharges and the flashover voltages. Four different water droplet arrangements were used, with eight different water conductivities in order to see the effect of the nanoparticle.
MgO Effect on The Dielectric Properties of BaTiO3
Authors: Boumous S. , Belkhiat S. , Kharchouche F.
Published: November 2020

The dielectric properties of barium titanate as functions of the MgO addition in various rates are investigated in this paper. The ceramics were prepared by conventional methods. X-ray diffraction, scanning electron microscopy and energy dispersive spectrometry, were applied to determine the structure and microstructure of the studied material. Phases MgO, TiO and TiO2, have been detected. Decrease of the grain size with increasing MgO content was observed. Measurements of εr, tgδ and resistance have been performed at temperatures ranging from 300C to 4000C. The electric permittivity (εr) showed a considerable decrease with increasing MgO concentration. Additionally, for low MgO concentration (10£mol.% MgO) a shift of the dielectric loss peak (tgδm) towards low temperatures was observed. When the MgO content was ≥15mol.% MgO the tgδm moved into higher temperatures. The obtained results indicate that the substitution of Mg2+ ions in B-site ions (Ti4+) had a significant influence on the values of εr, tgδ and the resistance increase of the ceramics.
Perspectives of Threat Modeling of a Secure Cloud Picture Archiving and Communication System
Authors: Awokola J. A. , Emuoyibofarhe O. N. , Omotosho A. , Emuoyibofarhe J. O. , Mebawondu J. O.
Published: November 2020

The Picture Archiving and Communication System (PACS) used in electronic health, is computationally enhanced by the migration into the cloud, which reduces the cost of storage space and equipment. However, cloud-PACS technology is susceptible to threats and vulnerabilities. This paper implements a threat modeling approach on a cloud-PACS framework, using Microsoft Threat Modelling Tools. Security requirements and mitigation strategies were formulated for the implementation of the framework, in order to improve cloud PACS security.
A Geoinformatics-based Framework for Surface Water Quality Mapping and Monitoring
Authors: Japitana M. V. , Burce M. E. C. , Ye C.
Published: November 2020

The management of water systems must be sustainable, something that requires systematic and comprehensive monitoring. However, the attempts to obtain a comprehensive water quality monitoring (WQM) program in developing countries are challenged due to the lack of an integrated framework and limited resources. At present, the Philippines has no systematized technical and operational monitoring approach, poor coordination and data collection system, and weak law enforcement. On the other hand, Geoinformatics promises a more convenient and cost-effective WQM to complement the traditional method. The goal of this study is to demonstrate how to maximize the use of Geonformatics in developing methods and models to address the lack of spatial trends, timely monitoring, and integrated monitoring framework that could lead to a sustainable WQM system. Results of this study showed that satellite images can be utilized to derive empirical models to estimate WQ parameters. The validation results showed that the estimated WQ values using the RS-based models have no significant difference when compared with the actual WQ values. Also, the WQ maps derived using Geographic Information System (GIS) were proven useful in providing better representation and analysis of spatial and temporal information that can provide a comprehensive and cost-effective reference for WQ monitoring and assessment.
Flash Flood Climatology in the Lower Region of Southern Sindh
Authors: Mahessar A. A. , Qureshi A. L. , Siming I. A. , Kori S. M. , Dars G. H. , Channa M. , Laghari A. N.
Published: November 2020

Climate change impact is felt at a global scale. One of its results is the abnormal rain occurrence during monsoon season. In recent years, visible changes due to unusual weather events in Pakistan’s hydrological cycle were observed in the form of intensification of the hydrological cycle with changing of precipitation events such as floods and prolonged droughts. Hence, abnormal rainfall occurred in regions of southern and northern parts of Sindh, like torrential river floods (2010), flash floods (2011-2012), unpredictable rainstorms, etc. causing loss of lives, damaging infrastructures and crops, structures, and inhabitant displacement. In 2011, heavy cumulative precipitation has been recorded in the southern Sindh districts and the coastal belt of Badin and the LBOD and Kotri surface drainage system achieved their extreme heights. Another example of erratic rain occurred from September 8 to September 13, 2011 and produced an extraordinary discharge of about 14000 cusecs against the designed discharge of 4600 cusecs in the LBOD and Kotri surface drainage systems overtopping drains from several locations and wreaking havoc in the whole area of the southern part of Sindh.
Mitigating Air Delay: An analysis of the Collaborative Trajectory Options Program
Authors: Pamplona D. A. , Alves C. J. P.
Published: November 2020

Congestion is a problem at major airports in the world. Airports, especially high-traffic ones, tend to be the bottleneck in the air traffic control system. The problem that arises for the airspace planner is how to mitigate air congestion and its consequent delay, which causes increased cost for airlines and discomfort for passengers. Most congestion problems are fixed on the day of operations in a tactically manner using operational enhancements measures. Collaborative Trajectory Options Program (CTOP) aims to improve air traffic management (ATM) considering National Airspace System (NAS) users business goals, particularities faced by each flight and airspace restrictions, making this process more flexible and financially stable for those involved. In CTOP, airlines share their route preferences with the air control authority, combining delay and reroute. When CTOP is created, each airline might decide its strategy without knowledge of other airline’s flights. Current solutions for this problem are based on greedy methods and game theory. There is potential space to improve. This paper examines CTOP and identifies important strategic changes to ATM adopting this philosophy, particularly in Brazil.
Analysis and Detection of a Target Gas System Based on TDLAS & LabVIEW
Authors: Alorifi F. , Ghaly S. M. A. , Shalaby M. Y. , Ali M. A. , Khan M. O.
Published: November 2020

This paper introduces detection techniques of target gas concentration based on infrared absorption spectrum method and the simulation of the gas detection system using LabVIEW. In this work, the harmonic detection is performed by wavelength modulation technique with a related frequency signal to cover the measured signal and get the gas absorption coefficient that can be analysed to give a gas concentration. A series of simulations are carried out to scan weak absorption lines and extract the second harmonic curve of the absorption spectrum of the target gas. The absorption and second harmonic curves are acquired by changing the parameters of the target gas concentration and line width. This work claims to be a contribution to the study and the comprehension of gas detection system based on tunable diode laser absorption spectroscopy and can serve as a basis for practical data acquisition.
Perspectives of an Enterprise Integration Plug-in System Architecture for Networked Manufacturing Systems
Authors: Ghannam A. N. , Mansour H. , El-Bastawissy A. , Hamed M.
Published: November 2020

This paper is a part of a research project funded by the Science and Technology Development Fund (STDF), to create a product serving the digital transformation of Egyptian manufacturing companies. It allows a manufacturing company to be a member of a distributed manufacturing network. The resulting system can be plugged into any ERP system. In this work, the limitation of a centralized integration entity to satisfy loosely coupling of distributed systems is overcome. The SOA framework and the remote method invocation (RMI) are applied using SOAP-XML technology. Enterprise integration patterns (EIP) were used in the architecture design.
Power Consumption Modeling based on Real-Time Data Traffic for Balancing Power Supply and Energy Demand to Develop Green Telecommunication Tower: A Case Study
Authors: Abdulmula A. M. O. , Sopian K. , Haw L. C.
Published: November 2020

Green telecommunication tower primarily depends on renewable energy and energy efficiency technologies. This study presents a power consumption model to estimate the load demand of a telecommunication tower (TT) to improve energy efficiency. The method is based on field measurements of real-time data traffic load of the entire operated macrocell telecommunication tower to balance power supply and energy demand. This advanced method is investigated using HOMER Pro simulation and compared with a widely accepted technique called overall peak load method for a chosen case study. The comparison simulation results showed that by using the power consumption model method, the energy-saving efficiency at the TT is improved by 24.19% and the size of the overall system is decreased by 33.33%. Consequently, the annualized cost is reduced by 25.7%. This optimum performance contributes to the effective development of green telecommunication towers.
Use of Rice Husk Ash as Cementitious Material in Concrete
Authors: Bheel N. , Abro A. W. , Shar I. A. , Dayo A .A. , Shaikh S. , Shaikh Z. H.
Published: November 2020

In this research, rice husk ash (RHA) was used as a partial substitute for cement in concrete to reduce its cost, and alternative processing methods using agricultural/industrial waste were found. The main objective of this study was to determine the fresh (flowability) and hardened (splitting tensile strength and compressive strength) concrete properties using RHA at 0%, 5%, 10%, 15% and 20% by weight. A total of 90 concrete samples (45 cubes and 45 cylinders) were prepared and cured on 7, 14, and 28 days to the design of target strength 28N/mm2, and ultimately, these concrete specimens were tested on UTM. Three concrete specimens were cast for each proportion and ultimately the average of the three concrete samples was taken as the final result. The flowability of fresh concrete decreases with increasing content of RHA in concrete. The results showed that the compressive and tensile strength of the concrete specimens increased by 11.8% and 7.31%, respectively by using 10% RHA at 28 days curing.
Controlling Measures for Cost Overrun Causes in Highway Projects of Sindh Province
Authors: Sohu S. , Abdullah A. H. , Nagapan S. , Rind T. A. , Jhatial A. A.
Published: November 2020

Cost overrun is a serious issue in the construction industry worldwide, including Pakistan. Cost overrun is a critical and serious issue found in highway projects among all construction projects in Pakistan. Cost overrun occurs when the final cost of the projects exceeds the actual cost of the project. The main objective of this research is to identify the main causes of cost overrun and to determine possible mitigation measures of the identified main causes of cost overrun from contractors of highway/road projects of Pakistan. In this study, a mixed mode (quantitative and qualitative) approach was used. A deep literature review helped to identify the 30 most common causes of cost overrun in the construction industry. In the first stage, a questionnaire was developed, and a survey was carried out among professional and experts who were working with contractors in highway projects. In the second stage, a semi-structured questionnaire was developed, and a survey was carried out to determine the possible mitigation measures of the identified main causes of cost overrun. Collected data for the first stage from experts were inserted in SPSS and were analyzed by using the average index method and the data of the second stage were analyzed by content analysis. It is expected that the findings of this research will be useful and helpful for the construction stakeholders to control and mitigate the major causes of cost overrun.
Application of Stochastic Analysis, Modeling and Simulation (SAMS) to Selected Hydrologic Data in the Middle East
Authors: Saada N. , Abdullah M. R. , Hamaideh A. , Abu-Romman A.
Published: November 2020

Water resources in the Middle East are very scarce and the management of these resources is a challenge. In this paper, the use of stochastic analysis, modeling, and simulation (SAMS) software package to selected hydrologic data in the Middle East (namely Jordan and Saudi Arabia) are explored. Modeling and simulation experiments were conducted to test the capabilities of SAMS to be used for stochastic modeling and simulation in the Middle East region. The hydrologic data used in this study consist of historic observed rainfall data of different lengths at various sites in Jordan and Saudi Arabia. The models used in this study include: autoregressive moving average (ARMA) models, periodic autoregressive moving average (PARMA) models, multi-site contemporaneous autoregressive moving average (CARMA) models, and temporal disaggregation models. Results indicate that SAMS can be used as a tool for stochastic modeling and simulation of hydrologic data in Jordan and Saudi Arabia. It is important for managers and decision makers of water resources in these countries to be able to use sophisticated tools such as SAMS while deciding water management policies in these countries.
Performance Evaluation of a Generator Differential Protection Function for a Numerical Relay
Authors: Le K. H. , Vu P. H.
Published: November 2020

This paper describes the advantages and disadvantages of a generator differential protection relay system which uses double slope characteristics of Areva P343, ABB REG670, SEL300G and GE G60. A Buon Tua Srah Hydropower Plant in Vietnam was selected as an example for the relay setting calculations of these characteristics. The performance of the introduced relay model was tested at various fault conditions in Matlab/Simulink. The results apply to the problems of solving the performance of the relay accurately and with reliable differential protection against internal faults, and keeping the generator stable on all external faults and in normal conditions. The simulation simplifies the process of selecting the relay and protection system. This can improve the quality of the protection system design early, thereby reducing the number of errors found later in the operation.
Creep Resistance of Polyethylene-based Nanocomposites
Authors: Alghamdi A. S.
Published: November 2020

The purpose of this work is to investigate the effects of carbon black (CB), carbon nanotubes (CNTs) and nanoclay sheets addition on the creep behavior of polyethylene-based nanocomposites synthesized with an in-house processing method. A blend of 75 wt.% UHMWPE and 25 wt.% HDPE, abbreviated to U75H25, was used as the hybrid PE matrix to accommodate the nanofillers. A 0.5 wt.% of CB, CNTs or nanosheets clay was embedded separately into the blend matrix in order to improve the creep resistance. The scanning electron microscope (SEM) and transmission electron microscope showed that the nanofillers were homogeneously dispersed in the U75H25. The addition of just 0.5 wt.% nanoclay resulted in a significant increase in the creep resistance of the polyethylene blend. Conversely, the addition of CB or CNTs caused a reduction in the creep resistance. The embedding of CNTs into the matrix resulted in creep behavior almost close to the creep behavior of pure UHMWPE. The Burger’s model was employed to understand the effect of the nanoparticle addition on the creep mechanism.
24-hour Fire Produced Effect on Reinforced Recycled Aggregates Concrete Beams
Authors: Buller A. H. , Oad M. , Memon B. A. , Sohu S.
Published: November 2020

In this article, the effect of prolonged fire (24-hour duration) on reinforced concrete beams made with recycled aggregates from demolished concrete was experimentally investigated. Demolished concrete was used recycled coarse aggregates in equal proportion with natural coarse aggregates. Normal and rich mix concrete with water-cement ratio equal to 0.54 were used. As a control specimen, beams with all-natural aggregates were also cast to compare with the results of the proposed beams. All beams were cured for 28 days and exposed to fire at 1000°C in an oven for 24 hours. After the elapse of this fire period, the beams were allowed to air cool, followed by testing till failure in a universal load testing machine. Comparison of the test results shows that rich mix concrete beams more reduction in flexural strength, more increase in maximum load carrying capacity and deflection than normal mix beams. The maximum reduction in flexural strength was 32.41% for beams cast with 50% RCA and rich mix. Although the fire duration used in this study is rare, yet the outcome provides guidelines for taking proper decisions for retrofitting/strengthening of the fire affected structure before putting it back in service.
Controlled Brushless De-Excitation Structure for Synchronous Generators
Authors: Chouaba S. E. , Barakat A.
Published: November 2020

The main weakness of the brushless excitation system in a synchronous generator (SG) is the slow de-excitation response obtained during a load rejection. That is why voltage overshoots may be observed on the generator terminals. This behavior is mainly due to the exciter machine response time and the rotating diode bridge which is not able to quickly de-excite the generator by negative excitation voltages. This paper presents a new brushless de-excitation structure able to perform a quick de-excitation of the generator by providing controlled negative excitation voltage to the generator main field winding. The proposed structure is based on a new brushless de-excitation machine, called a control machine, and mounted on the same shaft of the generator and the brushless exciter. The brushless control machine is a low power one and used to transfer the orders from the voltage regulator to the discharge system located on the rotor side of the main generator. The dynamic performance of the proposed de-excitation system is evaluated in terms of system stability, voltage regulation response times and voltage overshoots during different load rejection tests. The proposed system is compared to the conventional brushless excitation system without the proposed de-excitation structure. In addition, a comparison is done with the static excitation system. The simulation tests are realized on an experimentally validated model of 11kVA synchronous generator developed in Matlab/Simulink.
JPIAspectZ: A Formal Requirement Specification Language for Joint Point Interface AOP Applications
Authors: Vidal-Silva C. L. , Madariaga E. , Pham T. , Johnson F. , Urzua L. A. , Carter L.
Published: November 2020

Aspect-oriented software development (AOSD) solves a few issues of the object-oriented software development (OOSD) approach and adds a few more concerning modules and their relationships. Join point interface (JPI) is an AOSD methodology that by the definition of the interface between advised artifacts and aspects solves associated AOSD issues to get software with a high modularity level. Looking for a JPI software development approach, this article proposes and exemplifies the use of JPIAspectZ, an extension of the formal aspect-oriented language AspectZ for the software JPI requirement specifications. Mainly, JPIAspectZ looks for a concept and model consistency in a JPI software development process. Since the main JPI characteristics are the joining point interfaces definitions, i. e. explicit associations definition between aspects and advised modules, thus, by JPI, classes are no longer oblivious of possible interaction with aspects, and aspects, for their action effectiveness, do not depend anymore on signatures of advisable module components. JPIAspectZ fully supports these JPI principles. As JPI application examples, this article shows the formal requirements specification for classic aspect-oriented and JPI examples, along with describing the advantages and disadvantages of this language.
An Alternative System for Eccentrically Braced Frames Resisting Lateral Loads
Authors: Bishay-Girges N. W.
Published: November 2020

Eccentrically braced steel frames are structures used to resist lateral loads as they combine the ductility that is characteristic of moment frames and the stiffness associated with braced frames. Damper devices can be used as the main source of energy dissipation and have become more popular lately for the lateral control of structures. Control devices generally reduce damage by increasing structural safety, serviceability and preventing the building from collapse during vibration. This study focused on improving the performance of the structures with a proposed damping system, which has more advantages than eccentrically braced frames (EBFs). It can accommodate many architectural features and make construction and complementarity in the structures easier. The purpose of this study is to evaluate the performance of the structure with the proposed damping system and its construction in the building.