Search results for: retarding field energy analyzer
Commenced in January 2007
Frequency: Monthly
Edition: International
Paper Count: 5140

Search results for: retarding field energy analyzer

1180 Performance Enhancement of Analog Voltage Inverter with Adaptive Gain Control for Capacitive Load

Authors: Sun-Ki Hong, Yong-Ho Cho, Ki-Seok Kim, Tae-Sam Kang

Abstract:

Piezoelectric actuator is treated as RC load when it is modeled electrically. For some piezoelectric actuator applications, arbitrary voltage is required to actuate. Especially for unidirectional arbitrary voltage driving like as sine wave, some special inverter with circuit that can charge and discharge the capacitive energy can be used. In this case, the difference between power supply level and the object voltage level for RC load is varied. Because the control gain is constant, the controlled output is not uniform according to the voltage difference. In this paper, for charge and discharge circuit for unidirectional arbitrary voltage driving for piezoelectric actuator, the controller gain is controlled according to the voltage difference. With the proposed simple idea, the load voltage can have controlled smoothly although the voltage difference is varied. The appropriateness is proved from the simulation of the proposed circuit.

Keywords: Analog voltage inverter, Capacitive load, Gain control, DC-DC converter, Piezoelectric, Voltage waveform.

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1179 Sustainable Urban Waterfronts Using Sustainability Assessment Rating System

Authors: R. M. R. Hussein

Abstract:

Sustainable urban waterfront development is one of the most interesting phenomena of urban renewal in the last decades. However, there are still many cities whose visual image is compromised due to the lack of a sustainable urban waterfront development, which consequently affects the place of those cities globally. This paper aims to reimagine the role of waterfront areas in city design, with a particular focus on Egypt, so that they provide attractive, sustainable urban environments while promoting the continued aesthetic development of the city overall. This aim will be achieved by determining the main principles of a sustainable urban waterfront and its applications. This paper concentrates on sustainability assessment rating systems. A number of international case-studies, wherein a city has applied the basic principles for a sustainable urban waterfront and have made use of sustainability assessment rating systems, have been selected as examples which can be applied to the urban waterfronts in Egypt. This paper establishes the importance of developing the design of urban environments in Egypt, as well as identifying the methods of sustainability application for urban waterfronts.

Keywords: Sustainable Urban Waterfront, Green Infrastructure, Energy Efficient, Cairo.

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1178 Application of Biomass Ashes as Supplementary Cementitious Materials in the Cement Mortar Production

Authors: S. Šupić, M. Malešev, V. Radonjanin, M. Radeka, M. Laban

Abstract:

The production of low cost and environmentally friendly products represents an important step for developing countries. Biomass is one of the largest renewable energy sources, and Serbia is among the top European countries in terms of the amount of available and unused biomass. Substituting cement with the ashes obtained by the combustion of biomass would reduce the negative impact of concrete industry on the environment and would provide a waste valorization by the reuse of this type of by-product in mortars and concretes manufacture. The study contains data on physical properties, chemical characteristics and pozzolanic properties of obtained biomass ashes: wheat straw ash and mixture of wheat and soya straw ash in Serbia, which were, later, used as supplementary cementitious materials in preparation of mortars. Experimental research of influence of biomass ashes on physical and mechanical properties of cement mortars was conducted. The results indicate that the biomass ashes can be successfully used in mortars as substitutes of cement without compromising their physical and mechanical performances.

Keywords: Biomass, ash, cementitious material, mortar.

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1177 Model Canvas and Process for Educational Game Design in Outcome-Based Education

Authors: Ratima Damkham, Natasha Dejdumrong, Priyakorn Pusawiro

Abstract:

This paper explored the solution in game design to help game designers in the educational game designing using digital educational game model canvas (DEGMC) and digital educational game form (DEGF) based on Outcome-based Education program. DEGMC and DEGF can help designers develop an overview of the game while designing and planning their own game. The way to clearly assess players’ ability from learning outcomes and support their game learning design is by using the tools. Designers can balance educational content and entertainment in designing a game by using the strategies of the Business Model Canvas and design the gameplay and players’ ability assessment from learning outcomes they need by referring to the Constructive Alignment. Furthermore, they can use their design plan in this research to write their Game Design Document (GDD). The success of the research was evaluated by four experts’ perspectives in the education and computer field. From the experiments, the canvas and form helped the game designers model their game according to the learning outcomes and analysis of their own game elements. This method can be a path to research an educational game design in the future.

Keywords: Constructive alignment, constructivist theory, educational game, outcome-based education.

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1176 Bipolar Square Wave Pulses for Liquid Food Sterilization using Cascaded H-Bridge Multilevel Inverter

Authors: Hanifah Jambari, Naziha A. Azli, M. Afendi M. Piah

Abstract:

This paper presents the generation of bipolar square wave pulses with characteristics that are suitable for liquid food sterilization using a Cascaded H-bridge Multilevel Inverter (CHMI). Bipolar square waves pulses have been reported as stable for a longer time during the sterilization process with minimum heat emission and increased efficiency. The CHMI allows the system to produce bipolar square wave pulses and yielding high output voltage without using a transformer while fulfilling the pulse requirements for effective liquid food sterilization. This in turn can reduce power consumption and cost of the overall liquid food sterilization system. The simulation results have shown that pulses with peak output voltage of 2.4 kV, pulse width of between 1 2s and 1 ms at frequencies of 50 Hz and 100 Hz can be generated by a 7-level CHMI. Results from the experimental set-up based on a 5-level CHMI has indicated the potential of the proposed circuit in producing bipolar square wave output pulses with peak values that depends on the DC source level supplied to the CHMI modules, pulse width of between 12.5 2s and 1 ms at frequencies of 50 Hz and 100 Hz.

Keywords: pulsed electric field, multilevel inverter, bipolarsquare wave, food sterilization

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1175 Adsorptive Removal of Vapors of Toxic Sulfur Compounds using Activated Carbons

Authors: Meenakshi Goyal, Rashmi Dhawan

Abstract:

Adsorption of CS2 vapors has been studied on different types of activated carbons obtained from different source raw materials. The activated carbons have different surface areas and are associated with varying amounts of the carbon-oxygen surface groups. The adsorption of CS2 vapors is not directly related to surface area, but is considerably influenced by the presence of carbonoxygen surface groups. The adsorption decreases on increasing the amount of carbon-oxygen surface groups on oxidation and increases when these surface groups are eliminated on degassing. The adsorption is maximum in case of the 950°-degassed carbon sample which is almost completely free of any associated oxygen. The kinetic data as analysed by Empirical diffusion model and Linear driving force mass transfer model indicate that the adsorption does not involve Fickian diffusion but may be considered as a pseudo first order mass transfer process. The activation energy of adsorption and isosteric enthalpies of adsorption indicate that the adsorption does not involve interaction between CS2 and carbon-oxygen surface groups, but hydrophobic interactions between CS2 and C-C atoms in the carbon lattice.

Keywords: Adsorption, surface groups, adsorption kinetics, isosteric enthalpy of adsorption.

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1174 Best Starting Pitcher of the Chinese Professional Baseball League in 2009

Authors: Chih-Cheng Chen, Meng-Lung Lin, Yung-Tan Lee, Tien-Tze Chen, Ching-Yu Tseng

Abstract:

Baseball is unique among other sports in Taiwan. Baseball has become a “symbol of the Taiwanese spirit and Taiwan-s national sport". Taiwan-s first professional sports league, the Chinese Professional Baseball League (CPBL), was established in 1989. Starters pitch many more innings over the course of a season and for a century teams have made all their best pitchers starters. In this study, we attempt to determine the on-field performance these pitchers and which won the most CPBL games in 2009. We utilize the discriminate analysis approach to solve the problem, examining winning pitchers and their statistics, to reliably find the best starting pitcher. The data employed in this paper include innings pitched (IP), earned runs allowed (ERA) and walks plus hits per inning pitched (WPHIP) provided by the official website of the CPBL. The results show that Aaron Rakers was the best starting pitcher of the CPBL. The top 10 CPBL starting pitchers won 14 games to 8 games in the 2009 season. Though Fisher Discriminant Analysis, predicted to top 10 CPBL starting pitchers probably won 20 games to 9 games, more 1 game to 7 games in actually counts in 2009 season.

Keywords: Chinese Professional Baseball League, startingpitcher, Fisher's Discriminate analysis

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1173 Investigating the Effects of Thermal and Surface Energy on the Two-Dimensional Flow Characteristics of Oil in Water Mixture between Two Parallel Plates: A Lattice Boltzmann Method Study

Authors: W. Hasan, H. Farhat

Abstract:

A hybrid quasi-steady thermal lattice Boltzmann model was used to study the combined effects of temperature and contact angle on the movement of slugs and droplets of oil in water (O/W) system flowing between two parallel plates. The model static contact angle due to the deposition of the O/W droplet on a flat surface with simulated hydrophilic characteristic at different fluid temperatures, matched very well the proposed theoretical calculation. Furthermore, the model was used to simulate the dynamic behavior of droplets and slugs deposited on the domain’s upper and lower surfaces, while subjected to parabolic flow conditions. The model accurately simulated the contact angle hysteresis for the dynamic droplets cases. It was also shown that at elevated temperatures the required power to transport the mixture diminished remarkably.

Keywords: Lattice Boltzmann method, Gunstensen model, thermal, contact angle, high viscosity ratio.

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1172 Detection of Max. Optical Gain by Erbium Doped Fiber Amplifier

Authors: Abdulamgid.T. Bouzed, Suleiman. M. Elhamali

Abstract:

The technical realization of data transmission using glass fiber began after the development of diode laser in year 1962. The erbium doped fiber amplifiers (EDFA's) in high speed networks allow information to be transmitted over longer distances without using of signal amplification repeaters. These kinds of fibers are doped with erbium atoms which have energy levels in its atomic structure for amplifying light at 1550nm. When a carried signal wave at 1550nm enters the erbium fiber, the light stimulates the excited erbium atoms which pumped with laser beam at 980nm as additional light. The wavelength and intensity of the semiconductor lasers depend on the temperature of active zone and the injection current. The present paper shows the effect of the diode lasers temperature and injection current on the optical amplification. From the results of in- and output power one may calculate the max. optical gain by erbium doped fiber amplifier.

Keywords: Amplifier, erbium doped fiber, gain, lasers, temperature.

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1171 In situ Modelling of Lateral-Torsional Vibration of a Rotor-Stator with Multiple Parametric Excitations

Authors: B. X. Tchomeni, A. A. Alugongo, L. M. Masu

Abstract:

This paper presents a 4-DOF nonlinear model of a cracked de Laval rotor-stator system derived based on Energy Principles. The model has been used to simulate coupled torsionallateral response of the faulty system with multiple parametric excitations; rotor-stator-rub, a breathing transverse crack, eccentric mass and an axial force. Nonlinearity of a “breathing” crack is incorporated in the model using a simple hinge mechanism suitable for a shallow crack. Response of the system while passing via its critical speed with intermittent rotor-stator rub is analyzed. Effects of eccentricity with phase and acceleration are investigated. Features of crack, rub and eccentricity in vibration response are explored for condition monitoring. The presence of a crack and rub are observable in the power spectrum despite excitations by an axial force and rotor unbalance. Obtained results are consistent with existing literature and could be adopted into rotor condition monitoring strategies.

Keywords: Axial force, Crack, Nonlinear, Rotor-Stator, Rub.

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1170 Aiming at Optimization of Tracking Technology through Seasonally Tilted Sun Trackers: An Indian Perspective

Authors: Sanjoy Mukherjee

Abstract:

Discussions on concepts of Single Axis Tracker (SAT) are becoming more and more apt for developing countries like India not just as an advancement in racking technology but due to the utmost necessity of reaching at the lowest Levelized Cost of Energy (LCOE) targets. With this increasing competition and significant fall in feed-in tariffs of solar PV projects, developers are under constant pressure to secure investment for their projects and eventually earn profits from them. Moreover, being the second largest populated country, India suffers from scarcity of land because of higher average population density. So, to mitigate the risk of this dual edged sword with reducing trend of unit (kWh) cost at one side and utilization of land on the other, tracking evolved as the call of the hour. Therefore, the prime objectives of this paper are not only to showcase how STT proves to be an effective mechanism to get more gain in Global Incidence in collector plane (Ginc) with respect to traditional mounting systems but also to introduce Seasonally Tilted Tracker (STT) technology as a possible option for high latitude locations.

Keywords: Tracking system, grid-connected PV systems, cost reduction.

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1169 Development of Fuzzy Logic Control Ontology for E-Learning

Authors: Muhammad Sollehhuddin A. Jalil, Mohd Ibrahim Shapiai, Rubiyah Yusof

Abstract:

Nowadays, ontology is common in many areas like artificial intelligence, bioinformatics, e-commerce, education and many more. Ontology is one of the focus areas in the field of Information Retrieval. The purpose of an ontology is to describe a conceptual representation of concepts and their relationships within a particular domain. In other words, ontology provides a common vocabulary for anyone who needs to share information in the domain. There are several ontology domains in various fields including engineering and non-engineering knowledge. However, there are only a few available ontology for engineering knowledge. Fuzzy logic as engineering knowledge is still not available as ontology domain. In general, fuzzy logic requires step-by-step guidelines and instructions of lab experiments. In this study, we presented domain ontology for Fuzzy Logic Control (FLC) knowledge. We give Table of Content (ToC) with middle strategy based on the Uschold and King method to develop FLC ontology. The proposed framework is developed using Protégé as the ontology tool. The Protégé’s ontology reasoner, known as the Pellet reasoner is then used to validate the presented framework. The presented framework offers better performance based on consistency and classification parameter index. In general, this ontology can provide a platform to anyone who needs to understand FLC knowledge.

Keywords: Engineering knowledge, fuzzy logic control ontology, ontology development, table of contents.

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1168 The Impact of the General Data Protection Regulation on Human Resources Management in Schools

Authors: Alexandra Aslanidou

Abstract:

The General Data Protection Regulation (GDPR), concerning the protection of natural persons within the European Union with regard to the processing of personal data and on the free movement of such data, became applicable in the European Union (EU) on 25 May 2018 and transformed the way personal data were being treated under the Data Protection Directive (DPD) regime, generating sweeping organizational changes to both public sector and business. A social practice that is considerably influenced in the way of its day-to-day operations is Human Resource (HR) management, for which the importance of GDPR cannot be underestimated. That is because HR processes personal data coming in all shapes and sizes from many different systems and sources. The significance of the proper functioning of an HR department, specifically in human-centered, service-oriented environments such as the education field, is decisive due to the fact that HR operations in schools, conducted effectively, determine the quality of the provided services and consequently have a considerable impact on the success of the educational system. The purpose of this paper is to analyze the decisive role that GDPR plays in HR departments that operate in schools and in order to practically evaluate the aftermath of the Regulation during the first months of its applicability; a comparative use cases analysis in five highly dynamic schools, across three EU Member States, was attempted.

Keywords: General data protection regulation, human resource management, educational system.

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1167 Experimental Investigation the Effectiveness of Using Heat Pipe on the Spacecraft Mockup Panel

Authors: M. Abdou, M. K. Khalil

Abstract:

The heat pipe is a thermal device which allows efficient transport of thermal energy. The experimental work of this research was split into two phases; phase 1 is the development of the facilities, material and test rig preparation. Phase 2 is the actual experiments and measurements of the thermal control mockup inside the modified vacuum chamber (MVC). Due to limited funds, the development on the thermal control subsystem was delayed and the experimental facilities such as suitable thermal vacuum chamber with space standard specifications were not available from the beginning of the research and had to be procured over a period of time. In all, these delays extended the project by one and a half year. Thermal control subsystem needs a special facility and equipment to be tested. The available vacuum chamber is not suitable for the thermal tests. Consequently, the modification of the chamber was a must. A vacuum chamber has been modified to be used as a Thermal Vaccum Chamber (TVC). A MVC is a vacuum chamber modified by using a stainless mirror box with perfect reflectability and the infrared lamp connected with the voltage regulator to vary the lamp intensity as it will be illustrated through the paper.

Keywords: Heat pipe, thermal control, thermal vacuum chamber, satellite.

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1166 Tin (II) Chloride a Suitable Wetting Agent for AA1200 - SiC Composites

Authors: S. O. Adeosun, E. I. Akpan, S. A. Balogun, A. S. Abdulmunim

Abstract:

SiC reinforced Aluminum samples were produced by stir casting of liquid AA1200 aluminum alloy at 600-650ºC casting temperature. 83µm SiC particles were rinsed in 10g/l, 20g/l and 30g/l molar concentration of Sncl2 through cleaning times of 0, 60, 120, and 180 minutes. Some cast samples were tested for mechanical properties and some were subjected to heat treatment before testing. The SnCl2 rinsed SiC reinforced aluminum exhibited higher yield strength, hardness, stiffness and elongation which increases with cleaning concentration and time up to 120 minutes, compared to composite with untreated SiC. However, the impact energy resistance decreases with cleaning concentration and time. The improved properties were attributed to good wettability and mechanical adhesion at the fiber-matrix interface. Quenching and annealing the composite samples further improve the tensile/yield strengths, elongation, stiffness, hardness similar to those of the as-cast samples.

Keywords: Al-SIC, Aluminum, Composites, Intermetallic, Reinforcement, Tensile Strength, Wetting.

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1165 Blockchain Technology Applications in Patient Tracking Systems Regarding Privacy-Preserving Concerns and COVID-19 Pandemic

Authors: Farbod Behnaminia, Saeed Samet

Abstract:

The COVID-19 pandemic has paralyzed many lives until a vaccine has been available, which caused the so-called "new normal". COVID-19 is an infectious disease. It can cause significant illness or death in anyone. Governments and health officials tried to impose rules and regulations to avoid and slow down transmission. Therefore, software engineers worldwide developed applications to trace and track patients’ movements and notify others, mainly using Bluetooth. In this way, everyone could be informed whether they came in close contact with someone who has COVID-19 and take proper safety precautions. Because most of the applications use technologies that can potentially reveal the user’s identity and location, researchers have debated privacy preservation and how to improve user privacy during such pandemics. We conducted a comprehensive evaluation of the literature by looking for papers in the relevant field and dividing them into pre- and post-pandemic systems. Additionally, we discussed the many uses of blockchain technology in pandemic control. We found that two major obstacles facing blockchain implementation across many healthcare systems are scalability and privacy. The Polkadot platform is presented, along with a review of its efficacy in tackling current concerns. A more scalable healthcare system is achievable in near future using Polkadot as well as a much more privacy-preserving environment.

Keywords: Blockchain, Electronic Record Management, EHR, Privacy-Preserving, patient tracking, COVID-19, trust and confidence, Polkadot.

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1164 Preparation and Characterization of Maltodextrin Microcapsules Containing Walnut Green Husk Extract

Authors: Fatemeh Cheraghali, Saeedeh Shojaee-Aliabadi, Seyede Marzieh Hosseini, Leila Mirmoghtadaie

Abstract:

In recent years, the field of natural antimicrobial and antioxidant compounds is one of the main research topics in the food industry. Application of agricultural residues is mainly cheap, and available resources are receiving increased attention. Walnut green husk is one of the agricultural residues that is considered as natural compounds with biological properties because of phenolic compounds. In this study, maltodextrin 10% was used for microencapsulation of walnut green husk extract. At first, the extract was examined to consider extraction yield, total phenolic compounds, and antioxidant activation. The results showed the extraction yield of 81.43%, total phenolic compounds of 3997 [mg GAE/100 g], antioxidant activity [DPPH] of 84.85% for walnut green husk extract. Antioxidant activity is about 75%-81% and by DPPH. At the next stage, microencapsulation was done by spry-drying method. The microencapsulation efficiency was 72%-79%. The results of SEM tests confirmed this microencapsulation process. In addition, microencapsulated and free extract was more effective on gram-positive bacteria’s rather than the gram-negative ones. According to the study, walnut green husk can be used as a cheap antioxidant and antimicrobial compounds due to sufficient value of phenolic compounds.

Keywords: Biopolymer, microencapsulation, Spray-drying, Walnut green husk.

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1163 Identification of Disease Causing DNA Motifs in Human DNA Using Clustering Approach

Authors: G. Tamilpavai, C. Vishnuppriya

Abstract:

Studying DNA (deoxyribonucleic acid) sequence is useful in biological processes and it is applied in the fields such as diagnostic and forensic research. DNA is the hereditary information in human and almost all other organisms. It is passed to their generations. Earlier stage detection of defective DNA sequence may lead to many developments in the field of Bioinformatics. Nowadays various tedious techniques are used to identify defective DNA. The proposed work is to analyze and identify the cancer-causing DNA motif in a given sequence. Initially the human DNA sequence is separated as k-mers using k-mer separation rule. The separated k-mers are clustered using Self Organizing Map (SOM). Using Levenshtein distance measure, cancer associated DNA motif is identified from the k-mer clusters. Experimental results of this work indicate the presence or absence of cancer causing DNA motif. If the cancer associated DNA motif is found in DNA, it is declared as the cancer disease causing DNA sequence. Otherwise the input human DNA is declared as normal sequence. Finally, elapsed time is calculated for finding the presence of cancer causing DNA motif using clustering formation. It is compared with normal process of finding cancer causing DNA motif. Locating cancer associated motif is easier in cluster formation process than the other one. The proposed work will be an initiative aid for finding genetic disease related research.

Keywords: Bioinformatics, cancer motif, DNA, k-mers, Levenshtein distance, SOM.

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1162 A Lagrangian Hamiltonian Computational Method for Hyper-Elastic Structural Dynamics

Authors: Hosein Falahaty, Hitoshi Gotoh, Abbas Khayyer

Abstract:

Performance of a Hamiltonian based particle method in simulation of nonlinear structural dynamics is subjected to investigation in terms of stability and accuracy. The governing equation of motion is derived based on Hamilton's principle of least action, while the deformation gradient is obtained according to Weighted Least Square method. The hyper-elasticity models of Saint Venant-Kirchhoff and a compressible version similar to Mooney- Rivlin are engaged for the calculation of second Piola-Kirchhoff stress tensor, respectively. Stability along with accuracy of numerical model is verified by reproducing critical stress fields in static and dynamic responses. As the results, although performance of Hamiltonian based model is evaluated as being acceptable in dealing with intense extensional stress fields, however kinds of instabilities reveal in the case of violent collision which can be most likely attributed to zero energy singular modes.

Keywords: Hamilton's principle of least action, particle based method, hyper-elasticity, analysis of stability.

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1161 Inversion of Electrical Resistivity Data: A Review

Authors: Shrey Sharma, Gunjan Kumar Verma

Abstract:

High density electrical prospecting has been widely used in groundwater investigation, civil engineering and environmental survey. For efficient inversion, the forward modeling routine, sensitivity calculation, and inversion algorithm must be efficient. This paper attempts to provide a brief summary of the past and ongoing developments of the method. It includes reviews of the procedures used for data acquisition, processing and inversion of electrical resistivity data based on compilation of academic literature. In recent times there had been a significant evolution in field survey designs and data inversion techniques for the resistivity method. In general 2-D inversion for resistivity data is carried out using the linearized least-square method with the local optimization technique .Multi-electrode and multi-channel systems have made it possible to conduct large 2-D, 3-D and even 4-D surveys efficiently to resolve complex geological structures that were not possible with traditional 1-D surveys. 3-D surveys play an increasingly important role in very complex areas where 2-D models suffer from artifacts due to off-line structures. Continued developments in computation technology, as well as fast data inversion techniques and software, have made it possible to use optimization techniques to obtain model parameters to a higher accuracy. A brief discussion on the limitations of the electrical resistivity method has also been presented.

Keywords: Resistivity, inversion, optimization.

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1160 Seawater Desalination for Production of Highly Pure Water Using a Hydrophobic PTFE Membrane and Direct Contact Membrane Distillation (DCMD)

Authors: Ahmad Kayvani Fard, Yehia Manawi

Abstract:

Qatar’s primary source of fresh water is through seawater desalination. Amongst the major processes that are commercially available on the market, the most common large scale techniques are Multi-Stage Flash distillation (MSF), Multi Effect distillation (MED), and Reverse Osmosis (RO). Although commonly used, these three processes are highly expensive down to high energy input requirements and high operating costs allied with maintenance and stress induced on the systems in harsh alkaline media. Beside that cost, environmental footprint of these desalination techniques are significant; from damaging marine eco-system, to huge land use, to discharge of tons of GHG and huge carbon footprint. Other less energy consuming techniques based on membrane separation are being sought to reduce both the carbon footprint and operating costs is membrane distillation (MD). Emerged in 1960s, MD is an alternative technology for water desalination attracting more attention since 1980s. MD process involves the evaporation of a hot feed, typically below boiling point of brine at standard conditions, by creating a water vapor pressure difference across the porous, hydrophobic membrane. Main advantages of MD compared to other commercially available technologies (MSF and MED) and specially RO are reduction of membrane and module stress due to absence of trans-membrane pressure, less impact of contaminant fouling on distillate due to transfer of only water vapor, utilization of low grade or waste heat from oil and gas industries to heat up the feed up to required temperature difference across the membrane, superior water quality, and relatively lower capital and operating cost. To achieve the objective of this study, state of the art flat-sheet cross-flow DCMD bench scale unit was designed, commissioned, and tested. The objective of this study is to analyze the characteristics and morphology of the membrane suitable for DCMD through SEM imaging and contact angle measurement and to study the water quality of distillate produced by DCMD bench scale unit. Comparison with available literature data is undertaken where appropriate and laboratory data is used to compare a DCMD distillate quality with that of other desalination techniques and standards. Membrane SEM analysis showed that the PTFE membrane used for the study has contact angle of 127º with highly porous surface supported with less porous and bigger pore size PP membrane. Study on the effect of feed solution (salinity) and temperature on water quality of distillate produced from ICP and IC analysis showed that with any salinity and different feed temperature (up to 70ºC) the electric conductivity of distillate is less than 5 μS/cm with 99.99% salt rejection and proved to be feasible and effective process capable of consistently producing high quality distillate from very high feed salinity solution (i.e. 100000 mg/L TDS) even with substantial quality difference compared to other desalination methods such as RO and MSF.

Keywords: Membrane Distillation, Waste Heat, Seawater Desalination, Membrane, Freshwater, Direct Contact Membrane Distillation

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1159 Teachers' Preferences on the Issue of Segregation of Gifted Pupils in Czech Educational System

Authors: I. Kočvarová, E. Machů, N. Bártlová

Abstract:

The issue of inclusion - segregation in the current Czech educational system is highly actual due to changes in legislation. It applies primarily to pupils with special educational needs, but it should also apply to pupils with giftedness. The paper presents chosen results of an exploratory survey that was carried out on a convenience sample of 1101 Czech teachers working in lower secondary education (ISCED2). The rate of teachers´ agreement with segregation of gifted pupils in the education system was monitored during this investigation. A validated questionnaire of our own design was used for the purpose of this investigation. The results were compared across groups of teachers in terms of selected variables. Results show that 36,3 % of teachers incline to segregation (rather than inclusion) of gifted pupils. Teachers who are not educated in this field and have no experience in teaching gifted pupils tend to support their segregation more in comparison with other teachers. Teachers of specialized schools for gifted pupils paradoxically agree with segregation to a slightly lesser extent than teachers from traditional schools, but they also manifest the most hesitant attitude in this issue. Preferences for segregation of gifted pupils are not related to attitudes toward gifted pupils or teachers' self-evaluation in terms of care for the gifted. Investigation indicates that the issue of education of gifted children and their inclusion in the educational system needs more space within the further education of teachers.

Keywords: Educational system, evaluation, gifted pupil, inclusion, segregation, teacher.

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1158 Mechanical Behaviour of Sisal Fibre Reinforced Cement Composites

Authors: M. Aruna

Abstract:

Emphasis on the advancement of new materials and technology has been there for the past few decades. The global development towards using cheap and durable materials from renewable resources contributes to sustainable development. An experimental investigation of mechanical behaviour of sisal fibre-reinforced concrete is reported for making a suitable building material in terms of reinforcement. Fibre reinforced Composite is one such material, which has reformed the concept of high strength. Sisal fibres are abundantly available in the hot areas. Sisal fibre has emerged as a reinforcing material for concretes, used in civil structures. In this work, properties such as hardness and tensile strength of sisal fibre reinforced cement composites with 6, 12, 18 and 24% by weight of sisal fibres were assessed. Sisal fibre reinforced cement composite slabs with long sisal fibres were manufactured using a cast hand lay up technique. Mechanical response was measured under tension. The high energy absorption capacity of the developed composite system was reflected in high toughness values under tension respectively. 

Keywords: Sisal fibre, fibre-reinforced concrete, mechanical behaviour.

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1157 Students' Acceptance of Incorporating Emerging Communication Technologies in Higher Education in Kuwait

Authors: Bashaiar Alsanaa

Abstract:

Never has a revolution affected all aspects of humanity as the communication revolution during the past two decades. This revolution, with all its advances and utilities, swept the world thus becoming an integral part of our lives, hence giving way to emerging applications at the social, economic, political, and educational levels. More specifically, such applications have changed the delivery system through which learning is acquired by students. Interaction with educators, accessibility to content, and creative delivery options are but a few facets of the new learning experience now being offered through the use of technology in the educational field. With different success rates, third world countries have tried to pace themselves with use of educational technology in advanced parts of the world. One such country is the small rich-oil state of Kuwait which has tried to adopt the e-educational model, however, an evaluation of such trial is yet to be done. This study aimed to fill the void of research conducted around that topic. The study explored students' acceptance of incorporating communication technologies in higher education in Kuwait. Students' responses to survey questions presented an overview of the e-learning experience in this country, and drew a framework through which implications and suggestions for future research were discussed to better serve the advancement of e-education in developing countries.

Keywords: Communication technologies, E-learning, Kuwait, Social media

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1156 An Evaluation of the Oxide Layers in Machining Swarfs to Improve Recycling

Authors: J. Uka, B. McKay, T. Minton, O. Adole, R. Lewis, S. J. Glanvill, L. Anguilano

Abstract:

Effective heat treatment conditions to obtain maximum aluminium swarf recycling are investigated in this work. Aluminium swarf briquettes underwent treatments at different temperatures and cooling times to investigate the improvements obtained in the recovery of aluminium metal. The main issue for the recovery of the metal from swarfs is to overcome the constraints due to the oxide layers present in high concentration in the swarfs since they have a high surface area. Briquettes supplied by Renishaw were heat treated at 650, 700, 750, 800 and 850 ℃ for 1-hour and then cooled at 2.3, 3.5 and 5 ℃/min. The resulting material was analysed using SEM EDX to observe the oxygen diffusion and aluminium coalescence at the boundary between adjacent swarfs. Preliminary results show that, swarf needs to be heat treated at a temperature of 850 ℃ and cooled down slowly at 2.3 ℃/min to have thin and discontinuous alumina layers between the adjacent swarf and consequently allowing aluminium coalescence. This has the potential to save energy and provide maximum financial profit in preparation of swarf briquettes for recycling.

Keywords: Aluminium, swarf, oxide layers, recycle, reuse.

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1155 Neural Network Ensemble-based Solar Power Generation Short-Term Forecasting

Authors: A. Chaouachi, R.M. Kamel, R. Ichikawa, H. Hayashi, K. Nagasaka

Abstract:

This paper presents the applicability of artificial neural networks for 24 hour ahead solar power generation forecasting of a 20 kW photovoltaic system, the developed forecasting is suitable for a reliable Microgrid energy management. In total four neural networks were proposed, namely: multi-layred perceptron, radial basis function, recurrent and a neural network ensemble consisting in ensemble of bagged networks. Forecasting reliability of the proposed neural networks was carried out in terms forecasting error performance basing on statistical and graphical methods. The experimental results showed that all the proposed networks achieved an acceptable forecasting accuracy. In term of comparison the neural network ensemble gives the highest precision forecasting comparing to the conventional networks. In fact, each network of the ensemble over-fits to some extent and leads to a diversity which enhances the noise tolerance and the forecasting generalization performance comparing to the conventional networks.

Keywords: Neural network ensemble, Solar power generation, 24 hour forecasting, Comparative study

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1154 Application of Smart Temperature Information Material for The Evaluation of Heat Storage Capacity and Insulation Capacity of Exterior Walls

Authors: Chih-Yuan Chang, Jin-Chiuan Chang, San-Shan Hung, Cheng-Jui Hsu

Abstract:

The heat storage capacity of concrete in building shells is a major reason for excessively large electricity consumption induced by indoor air conditioning. In this research, the previously developed Smart Temperature Information Material (STIM) is embedded in two groups of exterior wall specimens (the control group contains reinforced concrete exterior walls and the experimental group consists of tiled exterior walls). Long term temperature measurements within the concrete are taken by the embedded STIM. Temperature differences between the control group and the experimental group in walls facing the four cardinal directions (east, west, south, and north) are evaluated. This study aims to provide a basic reference for the design of exterior walls and the selection of heat insulation materials.

Keywords: building envelope, sensor, energy, thermal insulation, reinforced concrete

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1153 Heat Flux Reduction Research in Hypersonic Flow with Opposing Jet

Authors: Yisheng Rong, Jian Sun, Weiqiang Liu, Renjun Zhan

Abstract:

A CFD study on heat flux reduction in hypersonic flow with opposing jet has been conducted. Flowfield parameters, reattachment point position, surface pressure distributions and heat flux distributions are obtained and validated with experiments. The physical mechanism of heat reduction has been analyzed. When the opposing jet blows, the freestream is blocked off, flows to the edges and not interacts with the surface to form aerodynamic heating. At the same time, the jet flows back to form cool recirculation region, which reduces the difference in temperature between the surface and the nearby gas, and then reduces the heat flux. As the pressure ratio increases, the interface between jet and freestream is gradually pushed away from the surface. Larger the total pressure ratio is, lower the heat flux is. To study the effect of the intensity of opposing jet more reasonably, a new parameter RPA has been introduced by combining the flux and the total pressure ratio. The study shows that the same shock wave position and total heat load can be obtained with the same RPA with different fluxes and the total pressures, which means the new parameter could stand for the intensity of opposing jet and could be used to analyze the influence of opposing jet on flow field and aerodynamic heating.

Keywords: opposing jet, aerodynamic heating, total pressure ratio, thermal protection system

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1152 Seismic Response of Braced Steel Frames with Shape Memory Alloy and Mega Bracing Systems

Authors: Mohamed Omar

Abstract:

Steel bracing members are widely used in steel  structures to reduce lateral displacement and dissipate energy during  earthquake motions. Concentric steel bracing provide an excellent  approach for strengthening and stiffening steel buildings. Using these  braces the designer can hardly adjust the stiffness together with  ductility as needed because of buckling of braces in compression. In  this study the use of SMA bracing and steel bracing (Mega) utilized  in steel frames are investigated. The effectiveness of these two  systems in rehabilitating a mid-rise eight-storey steel frames were  examined using time-history nonlinear analysis utilizing seismostruct  software. Results show that both systems improve the strength and  stiffness of the original structure but due to excellent behavior of  SMA in nonlinear phase and under compressive forces this system  shows much better performance than the rehabilitation system of  Mega bracing.

 

Keywords: Finite element analysis, seismic response, shapes memory alloy, steel frame, mega bracing.

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1151 Multi-Scale Damage and Mechanical Behavior of Sheet Molding Compound Composites Subjected to Fatigue, Dynamic, and Post-Fatigue Dynamic Loadings

Authors: M. Shirinbayan, J. Fitoussi, N. Abbasnezhad, A. Lucas, A. Tcharkhtchi

Abstract:

Sheet Molding Compounds (SMCs) with special microstructures are very attractive to use in automobile structures especially when they are accidentally subjected to collision type accidents because of their high energy absorption capacity. These are materials designated as standard SMC, Advanced Sheet Molding Compounds (A-SMC), Low-Density SMC (LD-SMC) and etc. In this study, testing methods have been performed to compare the mechanical responses and damage phenomena of SMC, LD-SMC, and A-SMC under quasi-static and high strain rate tensile tests. The paper also aims at investigating the effect of an initial pre-damage induced by fatigue on the tensile dynamic behavior of A-SMC. In the case of SMCs and A-SMCs, whatever the fibers orientation and applied strain rate are, the first observed phenomenon of damage corresponds to decohesion of the fiber-matrix interface which is followed by coalescence and multiplication of these micro-cracks and their propagations. For LD-SMCs, damage mechanisms depend on the presence of Hollow Glass Microspheres (HGM) and fibers orientation.

Keywords: SMC, LD-SMC, A-SMC, HGM, damage.

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