bluuebunny/crossref_metadata_2025 huggingface dataset:
Keyword Detection Techniques: A Comprehensive Study
Authors: Shaikh Z. A.
Published: November 2020

Automatic identification of influential segments from a large amount of data is an important part of topic detection and tracking (TDT). This can be done using keyword identification via collocation techniques, word co-occurrence networks, topic modeling and other machine learning techniques. This paper reviews existing traditional keyword extraction techniques and analyzes them to make useful insights and to give future directions for better automatic, unsupervised and language independent research. The paper reviews extant literature on existing traditional TDT approaches for automatic identification of influential segments from a large amount of data in keyword detection task. The current keyword detection techniques used by researchers have been discussed. Inferences have been drawn from current keyword detection techniques used by researchers, their advantages and disadvantages over the previous studies and the analysis results have been provided in tabular form. Although keyword detection has been widely explored, there is still a large scope and need for identifying topics from the uncertain user-generated data.
Numerical Study of the Thermal Behavior of a Composite Phase Change Material (PCM) Room
Authors: Ben Khedher N.
Published: November 2020

In this study, thermal performance of building walls integrated with phase change materials (PCM) was evaluated in terms of indoor temperature reduction and heat transfer time delay. PCM was incorporated as thin layer placed longitudinally within walls. The thermal performance of a room with and without PCM was evaluated numerically. The developed model is based on the enthalpy formulation for PCM melting and solidification, which is solved by an implicit finite difference method. The effect of PCM type on heat gain indoors was studied. Three phase change materials (n-octadecane, n-eicosane and calcium chloride hexahydrate) were tested in hot weather. Results showed that octadecane is the best in ensuring an indoor temperature close to 27 °C for the test room. Moreover, optimal thickness of the PCM layer within the walls is critical for heat transfer reduction and management and should be carefully chosen.
Water Availability in Snow Dominated Regions under Projected Climatic Variability: A Case Study of Alpine Catchment, Austria
Authors: Laghari A. N. , Soomro M. A. , Siyal Z. A. , Sandilo S. H. , Soomro T. A.
Published: November 2020

This study analyzes the response of various hydrological parameters and future water availability against anticipated climate variations in snow dominated alpine catchment in Austria. The parameters assessed are base flow, environmental flow, total flow, evapotranspiration, and snow cover duration. The distributed hydrological modeling system PREVAH is developed to assess the impacts through the combination of various climate change scenarios produced under the framework of the European project PRUDENCE. The model results clearly indicate an apparent shift from observed trends in monthly, seasonal and annual values. The mean annual changes observed by all model scenarios range between 45% to 60% decrease in snow cover duration, 15% to 20% increase in evapotranspiration, 5% to 15% decrease in base flow, and 15% to 25% decrease in total runoff values. However, mean annual changes observed in available water are marginal, just ranging from -3% to +2%. All regional model projections show more or less the same identical pattern of changes in analyzed parameters.
Utilizing Rice Husk Briquettes in Firing Crucible Furnace for Low Temperature Melting Metals in Nigeria
Authors: Musa N. A. , Akinbode F. O.
Published: November 2020

The search for alternative fuels for firing crucible furnace for low temperature melting metals has become mandatory, as a result of the pollution problem associated with the use of fossil fuels, the expense of electricity and also deforestation as a result of the use of charcoal. An agricultural waste, rice husk, in briquette form was used as an alternative fuel to fire crucible furnace to melt lead, zinc and aluminium. Results showed that lead and zinc melted and reached their pouring temperatures of 3840C and 5300C  in 70 minutes and 75 minutes  respectively. Aluminium was raised to a maximum temperature of 5200C  in 75 and 100 minutes.The average concentration of the pollutants (CO, SO2and NOX) were found to be  below the tolerance limit and that of TSP (Total Suspended Particulates) was found to be within the tolerance limit stipulated by Federal Environmental Protection Agency (FEPA) in Nigeria.
A Review of Anomaly Detection Techniques and Distributed Denial of Service (DDoS) on Software Defined Network (SDN)
Authors: Khairi M. H. H. , Ariffin S. H. S. , Abdul Latiff N. M. , Abdullah A. S. , Hassan M. K.
Published: November 2020

Software defined network (SDN) is a network architecture in which the network traffic may be operated and managed dynamically according to user requirements and demands. Issue of security is one of the big challenges of SDN because different attacks may affect performance and these attacks can be classified into different types. One of the famous attacks is distributed denial of service (DDoS). SDN is a new networking approach that is introduced with the goal to simplify the network management by separating the data and control planes. However, the separation leads to the emergence of new types of distributed denial-of-service (DDOS) attacks on SDN networks. The centralized role of the controller in SDN makes it a perfect target for the attackers. Such attacks can easily bring down the entire network by bringing down the controller. This research explains DDoS attacks and the anomaly detection as one of the famous detection techniques for intelligent networks.
Analysis of a DVR with Molten Carbonate Fuel Cell and Fuzzy Logic Control
Authors: Chakravorty J. , Sharma G. , Bhatia V.
Published: November 2020

As power demand constantly (and rapidly) increases and with the introduction of many sophisticated electronic devices, power quality issues are becoming a major problem for the power sector. In this context, issues of power quality, voltage swells and sags have become rather common. Custom power devices are generally used to solve this problem. A dynamic voltage restorer (DVR) is the most efficient and effective modern custom power device used in power distribution networks. In this paper a new DVR model is presented. The proposed DVR has a molten carbonate fuel cell (MCFC) as its DC source of supply with an ultra-capacitor along with a fuzzy controller as its controlling unit. The complete model is implemented in MATLAB/SIMULINK and the output of the proposed model is compared with conventional DVR model with a simple DC voltage source and a capacitor with the same fuzzy controller
Hall Current and Joule Heating Effects on Flow of Couple Stress Fluid with Entropy Generation
Authors: Opanuga A. A. , Okagbue H. I. , Bishop S. A. , Agboola O. O.
Published: November 2020

In this work, an analytical study of the effects of Hall current and Joule heating on the entropy generation rate of couple stress fluid is performed. It is assumed that the applied pressure gradient induces fluid motion. At constant velocity, hot fluid is injected at the lower wall and sucked off at the upper wall. The obtained equations governing the flow are transformed to dimensionless form and the resulting nonlinear coupled boundary value problems for velocity and temperature profiles are solved by Adomian decomposition method. Analytical expressions for fluid velocity and temperature are used to obtain the entropy generation and the irreversibility ratio. The effects of Hall current, Joule heating, suction/injection and magnetic field parameters are presented and discussed through graphs. It is found that Hall current enhances both primary and secondary velocities and entropy generation. It is also interesting that Joule heating raises fluid temperature and encourages entropy production. On the other hand Hartman number inhibited fluid motion while increase in suction/injection parameter resulted into a shift in flow symmetry.
3D Buoyancy Induced Heat Transfer in Triangular Solar Collector Having a Corrugated Bottom Wall
Authors: Aich W.
Published: November 2020

A numerical study of the natural convection heat transfer and fluid flow in 3D triangular solar collector having a corrugated bottom wall has been carried out using finite volume method. The aim of the study is to investigate how buoyancy forces inﬂuence airﬂow and temperature patterns inside the collector heated from below and cooled on its inclined walls while vertical ones are assumed to be perfect thermal insulators. Rayleigh number is the main parameter which changes from 103 to 105 and Prandtl number is ﬁxed at Pr=0.71. Results are reported in terms of particles trajectories, iso-surfaces of temperature, velocity magnitude and mean Nusselt number. It has been found that the flow structure is sensitive to the value of Rayleigh number and that heat transfer is enhanced with increasing of this parameter.
Formulation of Low Peclet Number Based Grid Expansion Factor for the Solution of the Convection Diffusion Equation
Authors: Abdullah A.
Published: November 2020

Convection-diffusion problems, due to its fundamental nature, are found in various science and engineering applications. In this research, the importance of the relationship between grid structure and flow parameters in such problems is emphasized. In particular, we propose a systematic technique in the selection of the grid expansion factor based on its logarithmic relationship with low Peclet number. Such linear mathematical connection between the two non-dimensional parameters serves as a guideline for more structured decision-making and improves the heuristic process in the determination of the computational domain grid for the numerical solution of convection-diffusion equations especially in the prediction of the concentration of the scalar. Results confirm the effectiveness of the new approach.
Feature Set Fusion for Spoof Iris Detection
Authors: Suvarchala P. V. L. , Srinivas Kumar S.
Published: November 2020

Iris recognition is considered as one of the most promising noninvasive biometric systems providing automated human identification. Numerous programs, like unique ID program in India - Aadhar, include iris biometric to provide distinctive identity identification to citizens. The active area is usually captured under non ideal imaging conditions. It usually suffers from poor brightness, low contrast, blur due to camera or subject's relative movement and eyelid eyelash occlusions. Besides the technical challenges, iris recognition started facing sophisticated threats like spoof attacks. Therefore it is vital that the integrity of such large scale iris deployments must be preserved. This paper presents the development of a new spoof resistant approach which exploits the statistical dependencies of both general eye and localized iris regions in textural domain using spatial gray level dependence matrix (SGLDM), gray level run length matrix (GLRLM) and contourlets in transform domain. We did experiments on publicly available fake and lens iris image databases. Correct classification rate obtained with ATVS-FIr iris database is 100% while it is 95.63% and 88.83% with IITD spoof iris databases respectively.
Motivation Factors for Adopting Building Information Modeling (BIM) in Iraq
Authors: Hatem W. A. , Abd A. M. , Abbas N. N.
Published: November 2020

Building information modeling (BIM) is an integrated and comprehensive system including whatever is related to a construction project and its stages. It represents a unified database for all project data through which project documents are available to all stakeholders. This paper evaluates the factors driving the adoption of BIM in Iraqi construction projects in different ministries and adopts quantitative approach to collect data by using a questionnaire survey specially prepared for this purpose which was distributed to experts in the ministries of the Iraqi construction sector. Returned data were subjected to proper statistical analysis. Results showed that the highest motivation for BIM application is to include it in the educational curricula, raise awareness through courses and workshops and contracting with international experts with experience in BIM field.
Using Length of Bilge Keel to Length of Waterline Ratio to Reduce Ship Rolling Motion
Authors: Putra P. K. D. N. Y. , Iskandar B. H. , Novita Y.
Published: November 2020

Fishing vessels must have good stability and manoeuvrability. Hull with round bottom shape has a relatively poor rolling duration compared to other forms. Rolling duration reduction will improve the quality of stability of the ship which can be obtained with bilge keel installation. The objectives of this research are 1) to compare each parameter value on model ship by using bilge keel and 2) to determine the minimum ratio of bilge keel's length toward waterline length on the model ship which still has the ability to reduce rolling motion on the ship. The method used was giving treatment to model ship and observing its rolling motion with different lengths of bilge keel. Based on the result of the research, it can be concluded that bilge keel installation with some length ratio toward length of waterline has different results significantly, and bilge keel with length ratio 0.2 still have effective capability in reducing the rolling motion of the model ship.
Prediction of Corner Columns’ Load Capacity Using Composite Material Analogy
Authors: Ali A. , Soomro Z. , Iqbal S. , Bhatti N. , Abro A. F.
Published: November 2020

There are numerous reasons for which concrete has become the most widely used construction material in buildings, one of them being its availability in different types, such as fiber-reinforced, lightweight, high strength, conventional and self-compacting concrete. This advantage is specially realized in high-rise building construction, where common construction practice is to use concretes of different types or strength classes in slabs and columns. Columns in such structures are generally made from concrete which is higher in compressive strength than the one used in floors or slabs. This raises issue of selection of concrete strength that should be used for estimating column capacity. Current paper tries to address this issue by testing nine (09) sandwich column specimens under axial loading. The floor concrete portion of the sandwich column was made of normal strength concrete, whereas column portions from comparatively higher strength concrete. Test results show that aspect ratio (h/b) influences the effective concrete strength of such columns. A previously adopted methodology of composite material analogy with some modifications has been found to predict well the capacity of columns where variation in floor and concrete strength is significant.
Assessing Power System Stability Following Load Changes and Considering Uncertainty
Authors: Ngo D. V. , Pham K. V. , Le D. D. , Le K. H. , Huynh K. V.
Published: November 2020

An increase in load capacity during the operation of a power system usually causes voltage drop and leads to system instability, so it is necessary to monitor the effect of load changes. This article presents a method of assessing the power system stability according to the load node capacity considering uncertainty factors in the system. The proposed approach can be applied to large-scale power systems for voltage stability assessment in real-time.
BlindSense: An Accessibility-inclusive Universal User Interface for Blind People
Authors: Khan A. , Khusro S. , Alam I.
Published: November 2020

A large number of blind people use smartphone-based assistive technology to perform their common activities. In order to provide a better user experience the existing user interface paradigm needs to be revisited. A new user interface model has been proposed in this paper. A simplified, semantically consistent, and blind-friendly adaptive user interface is provided. The proposed solution is evaluated through an empirical study on 63 blind people leveraging an improved user experience in performing common activities on a smartphone.
The Design and Development of a Semantic File System Ontology
Authors: Mashwani S. R. , Khusro S.
Published: November 2020

Semantic File System (SFS) is the vision for the future of file systems where information is given with explicit meaning to be processed by machines automatically and consumed by the users easily. SFSs extend traditional file systems to organize and retrieve information according to their semantics, intent and relationships with other resources rather than their physical locations. Ontology-based file system is a step to dissolve the borders between semantic web and semantic desktop to make the desktop part of a single giant web. Unfortunately, to the best of the authors’ current knowledge, so far, no effort has been exercised to develop an ontology for SFSs. This work contributes a SFS ontology, which extends NEPOMUK information element ontology framework into the domain of SFSs. The proposed SFS ontology is freely available with full technical definitions of terms and complete class hierarchy to be used for any purpose in information technology (IT). In addition, as a proof-of-concept implementation, we deploy the proposed ontology in the 360ᵒ SFS. Finally, to get most of the benefits of the ontology, this paper also presents a semantics-aware file manager.
Generation of a New Three Dimension Autonomous Chaotic Attractor and its Four Wing Type
Authors: Yu F. , Wang C.
Published: November 2020

In this paper, a new three-dimension (3D) autonomous chaotic system with a nonlinear term in the form of a hyperbolic sine (or cosine) function is reported. Some interesting and complex attractors are obtained. Basic dynamical properties of the new chaotic system are demonstrated in terms of Lyapunov exponents, Poincare mapping, fractal dimension and continuous spectrum. Meanwhile, for further enhancing the complexity of the topological structure of the new chaotic attractors, the attractors are changed from two-wing to four-wing through making axis doubly polarized, theoretically analyzed and numerically simulated. The obtained results clearly show that the chaotic system deserves further detailed investigation.
Analysis of Children’s Prosodic Features Using Emotion Based Utterances in Urdu Language
Authors: Khan S. , Ali S. A. , Sallar J.
Published: November 2020

Emotion plays a significant role in identifying the states of a speaker using spoken utterances. Prosodic features add sense in spoken utterances providing speaker emotions. The objective of this research is to analyze the behavior of prosodic features (individual and in combination with others’ prosodic features) with different learning classifiers on emotion based utterances of children in the Urdu language. In this paper, three different prosodic features (intensity, pitch, formant and their combinations) with five different learning classifiers(ANN, J-48, K-star, Naïve Bayes, decision stump) and four basic emotions (happy, sad, angry, and neutral) were used to develop the experimental framework. Demonstrative experiments expressed that, in terms of classification accuracy, artificial neural networks show significant results with both individual and combination of prosodic features in comparison with other learning classifiers.
Optimal Power Factor for the Reactive Load of Small Hydro Power Plants
Authors: Tsolov A. , Marinova B.
Published: November 2020

This article explores the operation algorithm of an excitation regulator of synchronous generators of small Hydro Power Plants (HPPs). The aim is to provide optimum economic parameters, consistent with the dynamically changing requirements of electric supply companies. An integral method for maintaining the power factor has been introduced. The proposed method ensures stable operation of generators in different working modes. It is implemented and the economic effect proved significant.
Significant Mitigation Measures for Critical Factors of Cost Overrun in Highway Projects of Pakistan
Authors: Sohu S. , Abdullah A. H. , Nagapan S. , Jhatial A. A. , Ullah K. , Bhatti I. A.
Published: November 2020

Stakeholders of the construction industry and academia are often facing problems of cost overrun. It has been observed that many constructions of highway projects are not completed at the approved cost due to certain factors. The objective of this research is to identify the cost overrun critical factors involved in highway projects with their significant mitigation measures. In this regard, literature review helped to identify 64 factors of cost overrun. Based on these 64 common factors, a preliminary survey was carried out among 30 selected respondents of highway projects to identify the critical factors of cost overrun and its possible mitigation measures. Results of the preliminary study reported 8 critical factors and 42 possible mitigation measures for the identified factors. Another questionnaire was established on the findings of the preliminary survey and was distributed among 350 stakeholders of highway projects to identify the significant mitigation measures of finding critical factors of cost overrun. In total, 8 significant mitigation measures were identified as causative and critical factors of cost overrun. The findings of this research would be helpful for the construction practitioners who are dealing with cost overrun issues in the highway projects of Pakistan.
A Classification Based Model to Assess Customer Behavior in Banking Sector
Authors: Rahman A. , Khan M. N. A.
Published: November 2020

A customer relationship management system is used to manage company relationships with current and possible customers. Following a thorough review of contemporary literature, different data mining techniques employed in different types of business, corporate sectors and organizations are analyzed. A model that would be helpful to identify customers’ behavior in the banking sector is then proposed. Three classifiers, k-NN, decision tree and artificial neural networks are used to predict customer behavior and are assessed in order to determine which classifier performs better for predicting customer behavior in the banking sector.
Outlining a Model of an Intelligent Decision Support System Based on Multi Agents
Authors: Benmoussa N. , Fakhouri Amr M. , Ahriz S. , Mansouri K. , Illoussamen E.
Published: November 2020

Performance optimization has become a necessity for the survival of enterprises as emerging technologies continue to impact them. To achieve this goal, decision making, a complex process which depends on big data and human issues, must be effective. As enterprises are being subjected to a multi-faceted pressure, they must ensure the optimization of their performance. This article investigates an intelligent decision support system (IDSS) based on multi agent systems (MAS). Our contribution consists in developing an intelligent model with an IDSS MAS approach that can detect and evaluate changes in both the external environment and the enterprise itself. This model is an adequate management tool for optimal and sustainable performance and offers real-time analytical, prospecting and optimization methods.
Car Black Box with Speed Control in Desired Areas for Collision Avoidance
Authors: Pawar D. R. , Poddar P.
Published: November 2020

This paper presents an advanced step to the concept of car black-box in developing a comprehensive vehicle safety system which would not only record the video and audio, but also try to prevent a possible collision by limiting the speed of the vehicle in accident-prone areas. In case of an accident, the time and location (co-ordinates) is sent through GSM to a preset number for immediate rescue and treatment. Recorded data can also be used for forensics, revealing the problems that caused the accident and give manufacturer an idea for improvement. So the motto is to develop an embedded integrated system consisting of a microcontroller, a power supply unit, sensors, memory, a motor driver unit and a GPS/GSM modem.
A Performance Comparative Analysis of Block Based Compressive Sensing and Line Based Compressive Sensing
Authors: Ebrahim M. , Adil S. H. , Nawaz D.
Published: November 2020

Compressive sensing (CS) is an innovative idea that has opened new areas for viable communication of correlated data. In this paper, a comparative performance analysis of two different variants of compressive sensing i.e. block based compressive sensing (BCS) and line based compressive censing (LCS) schemes is performed for natural images. The idea is to evaluate which variant performs better in terms of reconstruction quality and provides easy initial solution. The experimental analysis demonstrates that LCS scheme can enhance the image reconstruction at lower subrates by 0.5 dB to 2.5 dB, when compared to the BCS scheme.
Remediation of Sulfidic Wastewater by Aeration in the Presence of Ultrasonic Vibration
Authors: Ahmad F. , Al-Khazaal A. Z. , Ahmad N. , Alenezi I.
Published: November 2020

In the current study, the aerial oxidation of sodium sulfide in the presence of ultrasonic vibration is investigated. Sulfide analysis was carried out by the methylene blue method. Sodium sulfide is oxidized to elemental sulfur in the presence of ultrasonic vibration. The influence of air flow rate, initial sodium sulfide concentration and ultrasonic vibration intensity on the oxidation of sodium sulfide was investigated. The rate law equation regarding the oxidation of sulfide was determined from the experimental data. The order of reaction with respect to sulfide and oxygen was found to be 0.36 and 0.67 respectively. The overall reaction followed nearly first order kinetics.
Numerical Analysis of SHB Effects in Laterally-Coupled Distributed Feedback (LC-DFB) Lasers
Authors: Seifouri M. , Shahshahani F. , Faraji A.
Published: November 2020

In this paper the stability of Laterally-Coupled Distributed Feedback (LC-DFB) Lasers against the Spatial Hole Burning (SHB) effect is analyzed theoretically. The stability of the laser structure is evaluated using the flatness parameter F. It is shown that the LC-DFB lasers are stable in a wide range of different values ​​of ridge width and amplitude grating. The stability is sustained with increasing injection current. The results show that the flatness parameter is minimal for certain values ​​of the amplitude grating. The numerical calculations have been done by coupled wave and carrier rate equations on the basis of the transfer matrix method (TMM)
Compact Wideband Microstrip Patch Antenna based on High Impedance Surface
Authors: Nelaturi S. , Sarma N. V. S. N.
Published: November 2020

A compact single probe feed asymmetrical semicircular fractal boundary patch antenna based on HIS (high impedance surface) is proposed for wide bandwidth at Wi-Fi band. Circular polarization operation can be obtained by embedding semi-circle fractal curves along the edges of the square patch antenna. The 10-dB return loss bandwidth is 15.13% (2.32GHz-2.70GHz). The 3-dB axial ratio bandwidth is 4.11% (2.38GHz-2.48GHz). The close relationship between simulation results and measured results establishes the antenna usefulness.
Fabrication and Characterization of Organoclay Reinforced Polyester Based Hybrid Nanocomposite Materials
Authors: Zaman N. , Ahmed S. , Sanaullah M. , Rehman A. U. , Shar A. R. , Luhur M. R.
Published: November 2020

Synthesis and characterization of polyester nanocomposites was conducted in order to fabricate hybrid composite materials of polyester/montmorillonite (MMT). Polyester based polymeric nanocomposite materials were synthesized by incorporating MMT nanoclay to produce polyester/MMT hybrid materials. Successful efforts were made to fabricate hybrid nanocomposite materials based on matrix (polyester based) and reinforcement (organoclay) through sonication at 6 and 12 hours. Synthesized nanocomposite polymers (polyester/MMT) showed different properties when compared to the properties of MMT and polyester, which confirmed the successful fabrication of the desired material. The finest incorporation of polyester with MMT was verified by UV-Visible spectrophotometer, Fourier tranform-infrared (FTIR) and scanning electron microscopy (SEM). The disappearance of the Si-O characteristic peak was observed in the FTIR spectrum justifying the fabrication of the desired composite materials. Colored SEM images were used to confirm the fine homogenous distribution of organoclay. Black SEM images showed the matrix and reinforcement together. SEM, FTIR and UV-Visible spectroscopic techniques were used to analyze polyester based nanocomposite materials and organoclay was found randomly distributed in the polymeric matrix whereas on the surface was observed to be mostly uniform.
Operational Impact of RES Penetration on a Remote Diesel-Powered System in West Papua, Indonesia
Authors: Tuballa M. L. , Abundo M. L. S.
Published: November 2020

When a new power source connects to the distribution or transmission grid, an assessment of its impact is necessary. Technical studies must assess the possible effects of a proposed expansion, reinforcement or modification to evaluate the possible incidents that may occur. Typically, the calculations or analyses done are load flow, short-circuit, and transient stability. The possible renewable energy (RE) sources are determined first. The details of the existing electrical system, including the specifications for the elements used, are obtained and logical assumptions are utilized for those that are not known. The load flow analysis in the considered case revealed that the RE presence reduces diesel generation. The 119 kW PV array and the 54 kW tidal turbine displace most diesel generation: 22% of Gen 4 and 21.8% of Gen 5. The diesel-solar system brought the diesel generation down by 20.05% of Gen 4 and 20% of Gen 5. The diesel-tidal combination lessened the diesel generation by 1.92% of Gen 4 and 1.83% of Gen 5. Short-circuit analysis alerts indicating the operating percentages of the circuit breakers that are beyond their interrupting ratings are presented. The transient stability analysis depicts that RE sources affect the existing system and appear to be putting in more stress. The studied systems are not transient-stable based on the results. While it is relatively simple to plan to put up renewables in remote island systems, there are many factors to consider such as the possible impacts of the RE sources.
A Review on Self Compacting Concrete with Cementitious Materials and Fibers
Authors: Memon N. A. , Memon M. A. , Lakho N. A. , Memon F. A. , Keerio M. A. , Memon A. N.
Published: November 2020

Self-compacted concrete (SCC) is cast in the formwork without compaction and it fulfills the formwork due to its own weight. SCC is considered to have many advantages in comparison with conventional concrete like improved construction quality, faster construction activity, reduced cost etc. SCC is produced with the same ingredients of normal concrete. However, cementitious materials are also adopted to replace the cement content in SCC in order to use waste materials from industries and agricultural products. To further enhance the performance of SCC, different types of fibers are tried in order to produce fiber reinforced SCC. The fibers in the concrete bridge the cracks and diffuse the crack propagation which improves mechanical properties. In developed countries SCC has reasonable acceptance in construction industry but in developing countries like Pakistan has not gained acceptance. This paper is focused on undertaking a review of SCC with cement replacement and fiber reinforcement materials. The main objective of this paper is to compile the literature in order to understand the various properties of SCC in fresh and hardened state when these cement replacement materials and fibers are used.
Phi Shape UWB Antenna with Band Notch Characteristics
Authors: Ajetrao K. V. , Dhande A. P.
Published: November 2020

In this paper a novel band notch antenna in UWB frequency range is designed using split rings. Split rings are overlapped with designed monopole to give phi shape. The slit gap gives band-notch operation from 5.1GHz to 6.29GHz and from 4.94GHz to 5.91GHz for SPSSR and SPSCR antennas respectively. Simulated and measured results are in good agreement.
A Multi-Objective Optimization Model for Designing Business Portfolio in the Oil Industry
Authors: Kiamehr A. K. , Azar A. , Nayeri M. D.
Published: November 2020

Designing a business portfolio is one of the key decisions in developing corporate strategy. Most of the previous models are either non-quantitative or financial with an emphasis on optimizing a portfolio of investments or projects. This research represents a multi-objective optimization model that firstly, employs quantitative methods in strategic decision-making, and secondly, quantifies and considers non-financial, strategic variables in problem modeling. In this regard, links between businesses within a portfolio have been classified into four groups of market synergy, capabilities synergy, parenting costs, and sharing benefits, and have been structured as a conceptual model. Although the conceptual model can be applied to various industries, it is formulated for designing the portfolio of multi-business companies in Iran oil industry. The model has been solved for three cases by NSGA-II algorithm and strategic insights have been explored for different corporate types.
A Review of Ground Target Detection and Classification Techniques in Forward Scattering Radars
Authors: Kanona M. E. A. , Hamza M. G. , Abdalla A. G. , Hassan M. K.
Published: November 2020

This paper presents a review of target detection and classification in forward scattering radar (FSR) which is a special state of bistatic radars, designed to detect and track moving targets in the narrow region along the transmitter-receiver base line. FSR has advantages and incredible features over other types of radar configurations. All previous studies proved that FSR can be used as an alternative system for ground target detection and classification. The radar and FSR fundamentals were addressed and classification algorithms and techniques were debated. On the other hand, the current and future applications and the limitations of FSR were discussed.
A Numerical-Analytical Hybrid Approach for the Identification of SDM Solar Cell Unknown Parameters
Authors: Abbassi R. , Boudjemline A. , Abbassi A. , Torchani A. , Gasmi H. , Guesmi T.
Published: November 2020

Appropriate modeling and accurate parameter identification of solar cells are crucial in the optimization of photovoltaic (PV) systems. The single-diode model (SDM), consisting of an ideal current source, an ideal diode, a shunt resistor and a series resistor, is widely used to simulate the behavior of PV cells/panels. In this article, a hybrid approach for identification of solar cell SDM parameters is presented. This approach uses the inverse of the slope of the I-V curve under short-circuit and open-circuit conditions and combines numerical and analytical solutions. Indeed, knowing that numerical methods require appropriate initial values, the main idea of the proposed approach is to provide these solutions by analytical methods. The comparison of obtained results with experimental ones, based on manufacturer’s datasheet, proves that the algorithm thus obtained requires less information from the manufacturer and improves significantly the parameter identification accuracy.
Performance and Emission Analysis of a Diesel Engine Using Linseed Biodiesel Blends
Authors: Tunio M. M. , Luhur M. R. , Ali Z. M. , Daher U.
Published: November 2020

The core object of this study is to examine the suitability of linseeds for biodiesel production. The performance of an engine at different proportions of linseed blends with petro-diesel and the amount of emissions rate were investigated. Initially, linseed biodiesel was produced through transesterification process, and then it was mixed with petro-diesel fuel (D100) blends at volumetric ratios of 10% (LB10), 20% (LB20), and 30% (LB30). The properties of linseed biodiesel and its blends were investigated and compared with petro-diesel properties with reference to ASTM standards. It has been observed that the fuel properties of produced biodiesel are within ASTM permissible limits. The specific fuel consumption (SFC) of LB10 blend has been found lesser compared to LB20 and LB30. SFC of D100 is slightly less than that of all the blends. The brake thermal efficiency (BTE) of LB30 is greater than that of pure diesel D100 at maximum load and greater than that of LB10 and LB20. The heat dissipation rate in all linseed blends is found to have been less than that of D100. Carbon monoxide, carbon dioxide and NOx emissions of linseed blends are mostly lower in comparison with D100’s. Among all blends, LB10 was found more suitable alternative fuel for diesel engines and can be blended with petro diesel without engine modifications. It can be concluded that cultivation and production of linseed in Pakistan is very promising, therefore, it is recommended that proper exploitation and use of linseed for energy production may be encouraged through pertinent agencies of Pakistan.
Evaluation of window size in classification of epileptic short-term EEG signals using a Brain Computer Interface software
Authors: Tzimourta K. D. , Astrakas L. G. , Gianni A. M. , Tzallas A. T. , Giannakeas N. , Paliokas I. , Tsalikakis D. G. , Tsipouras M. G.
Published: November 2020

The complexity of epilepsy created a fertile ground for further research in automated methods, attempting to help the epileptologists’ task. Over the past years, great breakthroughs have emerged in computer-aided analysis and the advent of Brain Computer Interface (BCI) systems has greatly facilitated the automated seizure analysis. In this study, an evaluation of the window size in automated seizure detection is proposed. The EEG signals from the University of Bonn was employed and segmented into 24 epochs of different window lengths with 50% overlap each time. Statistical and spectral features were extracted in the OpenViBE scenario that were used to train four different classifiers. Results in terms of accuracy were above 80% for the Decision Trees classifier. Also, results indicated that different window sizes provide small variations in classification accuracy.
A Numerical Simulation Approach for Sunspot Area Calculation
Authors: Saadi S. , Chaker A.
Published: November 2020

The aim of this paper is the numerical simulation of the sunspot area (SSA) and its location on the walls and on the floor of a room with a single window facing south. The input parameters of the calculation code are the geometry of the cell located in the site of Ksar Challala (35.1 N, 2.19 E, 800 m) in Algeria for the 21st of March, June and December. The SSA is a function of the window’s area, the date and time, the orientation of the room, the altitude and the azimuth of the sun. The obtained results show that the western wall is affected by the sun in the morning, the eastern wall in the afternoon, the floor and the north wall in the middle of the day. By increasing the window area from 1 m2 to 2 m2 we found that the SSA increases considerably.
Performance Analysis of Different Control Strategies in a Z-source Inverter
Authors: Nayak B. , Dash S. S.
Published: November 2020

This paper presents the analysis for different control techniques in Z-source inverters. The voltage gain versus modulation index from simulation result is compared with the mathematical calculated voltage gain. Further detailed analysis of %THD, %harmonics of output voltage at different modulation indexes for different boosting techniques of a Z-source inverter are also performed with respect to the traditional VSI by MATLAB based simulation
On Some Unsolved Problems of Mathematica
Authors: Vorozhtsov E. V.
Published: November 2020

In this paper, some unsolved problems of the Mathematica software package are documented. At first, it is shown, using a number of examples, that the processing (simplification) of rational-fractional expressions involving powers in the general form, has been implemented in Maple more carefully than in Mathematica. Then, an error in Mathematica is demonstrated, leading to incorrect results at a change of a function’s body. For each example of symbolic or symbolic-numeric computations, alternate routes for solving the emerged problem are proposed (where possible). An added problem, related to Mathematica’s computing speed is documented, employing examples related to two-dimensional gas dynamics problems. It is shown that Mathematica computes rather slowly (about one thousand times slower) compared to a Fortran code.
A Hydrological Response Analysis Considering Climatic Variability: Case Study of Hunza Catchment
Authors: Laghari A. N. , Rauch W. , Soomro M. A.
Published: November 2020

The hydrological response of mountainous catchments particularly dependent on melting runoff is very vulnerable to climatic variability. This study is an attempt to assess hydrological response towards climatic variability of the Hunza catchment located in the mountainous chain of greater Hindu Kush-Himalaya (HKH) region. The hydrological response is analyzed through changes in snowmelt, ice melt and total runoff simulated through the application of the hydrological modeling system PREVAH under hypothetically developed climate change scenarios. The developed scenarios are based on changes in precipitation (Prp) and temperature (Tmp) and their combination. Under all the warmer scenarios, the increase in temperature systematically decreases the mean annual snow melt and increases significantly glacier melt volume. Temperature changes from 1°C to 4°C produce a large increase in spring and summer runoff, while no major variation was observed in the winter and autumn runoff. The maximum seasonal changes recorded under the Tmp+4°C, Prp+10% scenario.
A Method for Improving Renogram Production and Detection of Renal Pelvis using Mathematical Morphology on Scintigraphic Images
Authors: Xefteris S. , Tserpes K. , Varvarigou T.
Published: November 2020

Dynamic renal scintigraphy is a well-established imaging technique in nuclear medicine, used to detail both the organ's anatomy and function. However, the quality of the produced scintigrams provides an often unreliable diagnostic tool because of a rather bad signal-to-noise ratio and the fact that in certain occasions the regions of interest are too concentrated making it difficult for physician evaluation. The goal of this paper is to achieve a more accurate production of the renal activity graph, by avoiding the inclusion of image artifacts in the detection process. This is achieved by treating pixels as points in a two-dimensional Euclidean space, and exploiting set-theoretic properties and morphological operators. The evaluation of the method in a number of real patient’s scintigrams obtained in a depth of 5 years, showed that, in the majority of the cases, it is feasible to produce a more accurate renogram, for both kidneys and the renal pelvis region, that was helpful for the interpretation of the findings
On the Nature of Superconducting Precursors in Bi-Pb-Sr-Ca-Cu-O Compositions Fabricated by Hot Shock Wave Consolidation Technology
Authors: Chigvinadze J. , Ashinov S. , Mamniashvili G. , Donadze G. , Peikrishvili A. , Godibadze B.
Published: November 2020

In this paper, the possibility of critical temperature increasing of superconducting precursor Tс and the current bearing capacity in samples of Bi-Pb-Sr-Ca-Cu-O superconducting system fabricated using hot shock wave consolidation (HSWC) technology and investigated by the vibrating torsional magnetometry method, was studied. The advantage of HSWC technology over the traditional technologies of superconducting composites synthesis is that the high-density materials are made from the Bi-Pb-Sr-Ca-Cu-O superconducting system. After the action of explosive wave the superconductivity is retained. After the explosion a pronounced texture is formed indicating the creation of efficient pinning centers and thus, the increase of current-carrying ability of the obtained material. The critical temperature of potential superconducting precursor Tc of transition to superconducting state increased from Tc=107K for starting sample to Tc=138K, using the HSWC technology for synthesis of samples in range of pressures from P=5GPa up to P=12GPa.
A Modified Artificial Bee Colony for the Non-Smooth Dynamic Economic/Environmental Dispatch
Authors: Marouani Ι. , Boudjemline A. , Guesmi T. , Abdallah H. H.
Published: November 2020

This paper presents an improved artificial bee colony (ABC) technique for solving the dynamic economic emission dispatch (DEED) problem. Ramp rate limits, valve-point loading effects and prohibited operating zones (POZs) have been considered. The proposed technique integrates the grenade explosion method and Cauchy operator in the original ABC algorithm, to avoid random search mechanism. However, the DEED is a multi-objective optimization problem with two conflicting criteria which need to be minimized simultaneously. Thus, it is recommended to provide the best solution for the decision-makers. Shannon’s entropy-based method is used for the first time within the context of the on-line planning of generator outputs to extract the best compromise solution among the Pareto set. The robustness of the proposed technique is verified on six-unit and ten-unit system tests. Results proved that the proposed algorithm gives better optimum solutions in comparison with more than ten metaheuristic techniques.
A Parametric Study of Effect On Single Pile Integrity Due to An Adjacent Excavation Induced Stress Release in Soft Clay
Authors: Mangnejo D. A. , Soomro M. A. , Mangi N. , Halepoto I. A. , Dahri I. A.
Published: November 2020

To gain new insights into single pile responses to adjacent excavations in soft ground, numerical parametric studies are carried out. An advanced hypoplastic (clay) constitutive model which takes account of small-strain stiffness is adopted. The effects of excavation depths (i.e. formation level) relative to pile were investigated by simulating the excavation near the pile shaft (i.e., He/Lp=0.67), next to (He/Lp=1.00) and below the pile toe (He/Lp=1.33). Among the three cases, the excavation in case of He/Lp=1.33 resulted in the largest pile settlement (i.e. 7.6%dp). On the other hand, the largest pile bending moment was induced in case of He/Lp=0.67.
A Hybrid Data Mining Method for Customer Churn Prediction
Authors: Jamalian E. , Foukerdi R.
Published: November 2020

The expenses for attracting new customers are much higher compared to the ones needed to maintain old customers due to the increasing competition and business saturation. So customer retention is one of the leading factors in companies’ marketing. Customer retention requires a churn management, and an effective management requires an exact and effective model for churn prediction. A variety of techniques and methodologies have been used for churn prediction, such as logistic regression, neural networks, genetic algorithm, decision tree etc.. In this article, a hybrid method is presented that predicts customers churn more accurately, using data fusion and feature extraction techniques. After data preparation and feature selection, two algorithms, LOLIMOT and C5.0, were trained with different size of features and performed on test data. Then the outputs of the individual classifiers were combined with weighted voting. The results of applying this method on real data of a telecommunication company proved the effectiveness of the method.