Search results for: modified Riemann-Liouville fractional derivative
Commenced in January 2007
Frequency: Monthly
Edition: International
Paper Count: 2911

Search results for: modified Riemann-Liouville fractional derivative

1321 Determination of Some Etiologic Agents in Calves with Diarrhea

Authors: Nermin Isik, Ozlem Derinbay Ekici, Oguzhan Avci

Abstract:

The aim of this study was to determination of role infection in neonatal calves in Central Anatolian, Turkey. A total 300 fecal samples were collected from diarrheic neonatal calves, aged between 0–90 days from Konya, Karaman, and Aksaray from January to April 2014. Fecal specimens from calves with clinically diarrheic symptoms were examined for the presence of Bovine Coronavirus, Bovine Rotavirus, Cryptosporidium sp., and E. coli by commercially available capture direct enzyme linked immunosorbent assay (ELISA) kit and Modified Ziehl Neelsen method (MZN). Calves were grouped according to their age as follows: 1-14, 15-29, and 30-90 days. Cryptosporidium sp. infection was detected in 52.8%, 58.8%, and 39.2% by ELISA and 33.9%, 47%, 26.7% by MZN in the respective age groups. The seroprevalance of Rotavirus (12.5 %, 40 %, 12.5 %), Coronavirus (2.5%, 0%, 3.5%) and E. coli (5%, 4.7%, 8.9%) infections were determined according to the age groups respectively. Cryptosporidium sp. was the most detected enteropathogen (52 %) of calves and coronavirus was the least detected (2 %). The detection rate of the mixed enfection was 12.3%. In conclusion, it must be evaluated by mix infections in calves with diarrhea. These results will provide an important contribution against the factors that cause diarrhea

Keywords: cryptosporidium sp., bovine coronavirus, bovine rotavirus, E.coli, calve, ELISA

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1320 Wind Turbine Wake Prediction and Validation under a Stably-Stratified Atmospheric Boundary Layer

Authors: Yilei Song, Linlin Tian, Ning Zhao

Abstract:

Turbulence energetics and structures in the wake of large-scale wind turbines under the stably-stratified atmospheric boundary layer (SABL) can be complicated due to the presence of low-level jets (LLJs), a region of higher wind speeds than the geostrophic wind speed. With a modified one-k-equation, eddy viscosity model specified for atmospheric flows as the sub-grid scale (SGS) model, a realistic atmospheric state of the stable ABL is well reproduced by large-eddy simulation (LES) techniques. Corresponding to the precursor stably stratification, the detailed wake properties of a standard 5-MW wind turbine represented as an actuator line model are provided. An engineering model is proposed for wake prediction based on the simulation statistics and gets validated. Results confirm that the proposed wake model can provide good predictions for wind turbines under the SABL.

Keywords: large-eddy simulation, stably-stratified atmospheric boundary layer, wake model, wind turbine wake

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1319 Enhanced Imperialist Competitive Algorithm for the Cell Formation Problem Using Sequence Data

Authors: S. H. Borghei, E. Teymourian, M. Mobin, G. M. Komaki, S. Sheikh

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Imperialist competitive algorithm (ICA) is a recent meta-heuristic method that is inspired by the social evolutions for solving NP-Hard problems. The ICA is a population based algorithm which has achieved a great performance in comparison to other meta-heuristics. This study is about developing enhanced ICA approach to solve the cell formation problem (CFP) using sequence data. In addition to the conventional ICA, an enhanced version of ICA, namely EICA, applies local search techniques to add more intensification aptitude and embed the features of exploration and intensification more successfully. Suitable performance measures are used to compare the proposed algorithms with some other powerful solution approaches in the literature. In the same way, for checking the proficiency of algorithms, forty test problems are presented. Five benchmark problems have sequence data, and other ones are based on 0-1 matrices modified to sequence based problems. Computational results elucidate the efficiency of the EICA in solving CFP problems.

Keywords: cell formation problem, group technology, imperialist competitive algorithm, sequence data

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1318 Design of a Vehicle Door Structure Based on Finite Element Method

Authors: Tawanda Mushiri, Charles Mbohwa

Abstract:

The performance of door assembly is very significant for the vehicle design. In the present paper, the finite element method is used in the development processes of the door assembly. The stiffness, strength, modal characteristic, and anti-extrusion of a newly developed passenger vehicle door assembly are calculated and evaluated by several finite element analysis commercial software. The structural problems discovered by FE analysis have been modified and finally achieved the expected door structure performance target of this new vehicle. The issue in focus is to predict the performance of the door assembly by powerful finite element analysis software, and optimize the structure to meet the design targets. It is observed that this method can be used to forecast the performance of vehicle door efficiently when it’s designed. In order to reduce lead time and cost in the product development of vehicles more development will be made virtually.

Keywords: vehicle door, structure, strength, stiffness, modal characteristic, anti-extrusion, Finite Element Method

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1317 Cold Plasma Surface Modified Electrospun Microtube Array Membrane for Chitosan Immobilization and Their Properties

Authors: Ko-Shao Chen, Yun Tsao, Chia-Hsuan Tsen, Chien-Chung Chen, Shu-Chuan Liao

Abstract:

Electrospun microtube array membranes (MTAMs) made of PLLA (poly-L-lactic acid) have wide potential applications in tissue engineering. However, their surface hydrophobicity and poor biocompatability have limited their further usage. In this study, the surface of PLLA MTAMs were made hydrophilic by introducing extra functional groups, such as peroxide, via an acetic acid plasma (AAP). UV-graft polymerization of acrylic acid (G-AAc) was then used to produce carboxyl group on MTAMs surface, which bonded covalently with chitosan through EDC / NHS crosslinking agents. To evaluate the effects of the surface modification on PLLA MTAMs, water contact angle (WCA) measurement and cell compatibility tests were carried out. We found that AAP treated electrospun PLLA MTAMs grafted with AAc and, finally, with chitosan immobilized via crosslinking agent, exhibited improved hydrophilic and cell compatibility.

Keywords: plasma, EDC/NHS, UV grafting, Chitosan, microtube array membrane (MTAMs)

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1316 Increased Stability of Rubber-Modified Asphalt Mixtures to Swelling, Expansion and Rebound Effect during Post-Compaction

Authors: Fernando Martinez Soto, Gaetano Di Mino

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The application of rubber into bituminous mixtures requires attention and care during mixing and compaction. Rubber modifies the properties because it reacts in the internal structure of bitumen at high temperatures changing the performance of the mixture (interaction process of solvents with binder-rubber aggregate). The main change is the increasing of the viscosity and elasticity of the binder due to the larger sizes of the rubber particles by dry process but, this positive effect is counteracted by short mixing times, compared to wet technology, and due to the transport processes, curing time and post-compaction of the mixtures. Therefore, negative effects as swelling of rubber particles, rebounding effect of the specimens and thermal changes by different expansion of the structure inside the mixtures, can change the mechanical properties of the rubberized blends. Based on the dry technology, different asphalt-rubber binders using devulcanized or natural rubber (truck and bus tread rubber), have served to demonstrate these effects and how to solve them into two dense-gap graded rubber modified asphalt concrete mixes (RUMAC) to enhance the stability, workability and durability of the compacted samples by Superpave gyratory compactor method. This paper specifies the procedures developed in the Department of Civil Engineering of the University of Palermo during September 2016 to March 2017, for characterizing the post-compaction and mix-stability of the one conventional mixture (hot mix asphalt without rubber) and two gap-graded rubberized asphalt mixes according granulometry for rail sub-ballast layers with nominal size of Ø22.4mm of aggregates according European standard. Thus, the main purpose of this laboratory research is the application of ambient ground rubber from scrap tires processed at conventional temperature (20ºC) inside hot bituminous mixtures (160-220ºC) as a substitute for 1.5%, 2% and 3% by weight of the total aggregates (3.2%, 4.2% and, 6.2% respectively by volumetric part of the limestone aggregates of bulk density equal to 2.81g/cm³) considered, not as a part of the asphalt binder. The reference bituminous mixture was designed with 4% of binder and ± 3% of air voids, manufactured for a conventional bitumen B50/70 at 160ºC-145ºC mix-compaction temperatures to guarantee the workability of the mixes. The proportions of rubber proposed are #60-40% for mixtures with 1.5 to 2% of rubber and, #20-80% for mixture with 3% of rubber (as example, a 60% of Ø0.4-2mm and 40% of Ø2-4mm). The temperature of the asphalt cement is between 160-180 ºC for mixing and 145-160 ºC for compaction, according to the optimal values for viscosity using Brookfield viscometer and 'ring and ball' - penetration tests. These crumb rubber particles act as a rubber-aggregate into the mixture, varying sizes between 0.4mm to 2mm in a first fraction, and 2-4mm as second proportion. Ambient ground rubber with a specific gravity of 1.154g/cm³ is used. The rubber is free of loose fabric, wire, and other contaminants. It was found optimal results in real beams and cylindrical specimens with each HMA mixture reducing the swelling effect. Different factors as temperature, particle sizes of rubber, number of cycles and pressures of compaction that affect the interaction process are explained.

Keywords: crumb-rubber, gyratory compactor, rebounding effect, superpave mix-design, swelling, sub-ballast railway

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1315 Bacteriophages for Sustainable Wastewater Treatment: Application in Black Water Decontamination with an Emphasis to DRDO Biotoilet

Authors: Sonika Sharma, Mohan G. Vairale, Sibnarayan Datta, Soumya Chatterjee, Dharmendra Dubey, Rajesh Prasad, Raghvendra Budhauliya, Bidisha Das, Vijay Veer

Abstract:

Bacteriophages are viruses that parasitize specific bacteria and multiply in metabolising host bacteria. Bacteriophages hunt for a single or a subset of bacterial species, making them potential antibacterial agents. Utilizing the ability of phages to control bacterial populations has several applications from medical to the fields of agriculture, aquaculture and the food industry. However, harnessing phage based techniques in wastewater treatments to improve quality of effluent and sludge release into the environment is a potential area for R&D application. Phage mediated bactericidal effect in any wastewater treatment process has many controlling factors that lead to treatment performance. In laboratory conditions, titer of bacteriophages (coliphages) isolated from effluent water of a specially designed anaerobic digester of human night soil (DRDO Biotoilet) was successfully increased with a modified protocol of the classical double layer agar technique. Enrichment of the same was carried out and efficacy of the phage enriched medium was evaluated at different conditions (specific media, temperature, storage conditions). Growth optimization study was carried out on different media like soybean casein digest medium (Tryptone soya medium), Luria-Bertani medium, phage deca broth medium and MNA medium (Modified nutrient medium). Further, temperature-phage yield relationship was also observed at three different temperatures 27˚C, 37˚C and 44˚C at laboratory condition. Results showed the higher activity of coliphage 27˚C and at 37˚C. Further, addition of divalent ions (10mM MgCl2, 5mM CaCl2) and 5% glycerol resulted in a significant increase in phage titer. Besides this, effect of antibiotics addition like ampicillin and kanamycin at different concentration on plaque formation was analysed and reported that ampicillin at a concentration of 1mg/ml ampicillin stimulates phage infection and results in more number of plaques. Experiments to test viability of phage showed that it can remain active for 6 months at 4˚C in fresh tryptone soya broth supplemented with fresh culture of coliforms (early log phase). The application of bacteriophages (especially coliphages) for treatment of effluent of human faecal matter contaminated effluent water is unique. This environment-friendly treatment system not only reduces the pathogenic coliforms, but also decreases the competition between nuisance bacteria and functionally important microbial populations. Therefore, the phage based cocktail to treat fecal pathogenic bacteria present in black water has many implication in wastewater treatment processes including ‘DRDO Biotoilet’, which is an ecofriendly appropriate and affordable human faecal matter treatment technology for different climates and situations.

Keywords: wastewater, microbes, virus, biotoilet, phage viability

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1314 Spatial Data Mining by Decision Trees

Authors: Sihem Oujdi, Hafida Belbachir

Abstract:

Existing methods of data mining cannot be applied on spatial data because they require spatial specificity consideration, as spatial relationships. This paper focuses on the classification with decision trees, which are one of the data mining techniques. We propose an extension of the C4.5 algorithm for spatial data, based on two different approaches Join materialization and Querying on the fly the different tables. Similar works have been done on these two main approaches, the first - Join materialization - favors the processing time in spite of memory space, whereas the second - Querying on the fly different tables- promotes memory space despite of the processing time. The modified C4.5 algorithm requires three entries tables: a target table, a neighbor table, and a spatial index join that contains the possible spatial relationship among the objects in the target table and those in the neighbor table. Thus, the proposed algorithms are applied to a spatial data pattern in the accidentology domain. A comparative study of our approach with other works of classification by spatial decision trees will be detailed.

Keywords: C4.5 algorithm, decision trees, S-CART, spatial data mining

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1313 Nadler's Fixed Point Theorem on Partial Metric Spaces and its Application to a Homotopy Result

Authors: Hemant Kumar Pathak

Abstract:

In 1994, Matthews (S.G. Matthews, Partial metric topology, in: Proc. 8th Summer Conference on General Topology and Applications, in: Ann. New York Acad. Sci., vol. 728, 1994, pp. 183-197) introduced the concept of a partial metric as a part of the study of denotational semantics of data flow networks. He gave a modified version of the Banach contraction principle, more suitable in this context. In fact, (complete) partial metric spaces constitute a suitable framework to model several distinguished examples of the theory of computation and also to model metric spaces via domain theory. In this paper, we introduce the concept of almost partial Hausdorff metric. We prove a fixed point theorem for multi-valued mappings on partial metric space using the concept of almost partial Hausdorff metric and prove an analogous to the well-known Nadler’s fixed point theorem. In the sequel, we derive a homotopy result as an application of our main result.

Keywords: fixed point, partial metric space, homotopy, physical sciences

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1312 Preparation of Ag-Doped and MOFs Coupled-LaFeO₃ Nanosheet for Electrochemical CO₂ Conversion

Authors: Iltaf Khan, Munzir H. Suliman, Muhammad Usman

Abstract:

The rapid growth of modern industries has led to increased energy demand and worsened fossil fuel depletion, resulting in global warming, while organic pollutants pose significant threats to aquatic environments due to their stability, insolubleness, and non-biodegradability. So, scientists are investigating high-performance materials to resolve these issues. In this study, we prepared LaFeO₃ nanosheets (LFONS) employing a solvothermal method via a soft template such as polyvinylpyrrolidone (PVP). The LFONS have good performance regarding surface area and charge separation as compared to LaFeO₃ nanoparticles (LFONP). To improve the efficiency of LFONS, it was further modified with Ag and ZIF-67 and utilized for CO₂ conversion. Herein, the results confirm that Ag-doped and ZIF-67 coupled LFONS (ZIF-67/Ag-LFONS) exhibit superior performance compared to pristine LFONP. In addition, the stability tests confirm that our optimal sample is the most active and stable one among various nanocomposites. Ultimately, our studies will open a new pave for cost-effective, eco-friendly, and electroactive nanomaterials for CO₂ conversion.

Keywords: LaFeO₃ nanosheets, Ag incorporation, MOFs coupling, CO₂ conversion

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1311 Maximum Power Point Tracking Using Fuzzy Logic Control for a Stand-Alone PV System with PI Controller for Battery Charging Based on Evolutionary Technique

Authors: Mohamed A. Moustafa Hassan, Omnia S .S. Hussian, Hany M. Elsaved

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This paper introduces the application of Fuzzy Logic Controller (FLC) to extract the Maximum Power Point Tracking (MPPT) from the PV panel. In addition, the proportional integral (PI) controller is used to be the strategy for battery charge control according to acceptable performance criteria. The parameters of the PI controller have been tuned via Modified Adaptive Accelerated Coefficient Particle Swarm Optimization (MAACPSO) technique. The simulation results, using MATLAB/Simulink tools, show that the FLC technique has advantages for use in the MPPT problem, as it provides a fast response under changes in environmental conditions such as radiation and temperature. In addition, the use of PI controller based on MAACPSO results in a good performance in terms of controlling battery charging with constant voltage and current to execute rapid charging.

Keywords: battery charging, fuzzy logic control, maximum power point tracking, PV system, PI controller, evolutionary technique

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1310 Dynamic Self-Scheduling of Pumped-Storage Power Plant in Energy and Ancillary Service Markets Using Sliding Window Technique

Authors: P. Kanakasabapathy, S. Radhika

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In the competitive electricity market environment, the profit of the pumped-storage plant in the energy market can be maximized by operating it as a generator, when market clearing price is high and as a pump, to pump water from lower reservoir to upper reservoir, when the price is low. An optimal self-scheduling plan has been developed for a pumped-storage plant, carried out on weekly basis in order to maximize the profit of the plant, keeping into account of all the major uncertainties such as the sudden ancillary service delivery request and the price forecasting errors. For a pumped storage power plant to operate in a real time market successive self-scheduling has to be done by considering the forecast of the day-ahead market and the modified reservoir storage due to the ancillary service request of the previous day. Sliding Window Technique has been used for successive self-scheduling to ensure profit for the plant.

Keywords: ancillary services, BPSO, power system economics, self-scheduling, sliding window technique

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1309 Separation and Purification of Oligostilbenes Using HPLC with Dereplication Strategy

Authors: Nurhuda Manshoor, Mohd Fazirulrahman Fathil, Muhammad Hakim Jaafar, Mohd Amirul S. A. Jalil

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The leaves of Neobalanocarpus heimii were investigated for their oligostilbene contents. Prior to isolation process, the determinations of compounds were based on mass spectrometric fragmentation patterns. Three compounds, heimiol B, hopeaphenol, and vaticaphenol A were identified directly from the crude extract. Preparative high-performance liquid chromatography (HPLC) was used to isolate and purify the other compounds. The purified compounds were then analyzed using NMR spectroscopy to identify the compound structure and stereochemistry. The method employed for the research modified to comply with different HPLC techniques such as preparative and analytical techniques. The crude sample was injected into preparative HPLC to obtain several fractions which consist of oligostilbene mixture. The fractions were further isolated using analytical HPLC to obtain four pure compounds. The compounds then were characterized using nuclear magnetic resonance (NMR). The result shows that the leaves extract of Neobalanocarpus heimii contain three oligostilbenes, namely vaticanol A, balanocarpol, and vaticaphenol A, and a galactopyranose.

Keywords: balanocarpol, hemiol B, hopeaphenol, vaticanol A, vaticaphenol A

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1308 Detectability of Malfunction in Turboprop Engine

Authors: Tomas Vampola, Michael Valášek

Abstract:

On the basis of simulation-generated failure states of structural elements of a turboprop engine suitable for the busy-jet class of aircraft, an algorithm for early prediction of damage or reduction in functionality of structural elements of the engine is designed and verified with real data obtained at dynamometric testing facilities of aircraft engines. Based on an expanding database of experimentally determined data from temperature and pressure sensors during the operation of turboprop engines, this strategy is constantly modified with the aim of using the minimum number of sensors to detect an inadmissible or deteriorated operating mode of specific structural elements of an aircraft engine. The assembled algorithm for the early prediction of reduced functionality of the aircraft engine significantly contributes to the safety of air traffic and to a large extent, contributes to the economy of operation with positive effects on the reduction of the energy demand of operation and the elimination of adverse effects on the environment.

Keywords: detectability of malfunction, dynamometric testing, prediction of damage, turboprop engine

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1307 Investigating Optical Properties of Unsaturated Polyurethane Matrix and Its Glass Fiber Composite Under Extreme Temperatures

Authors: Saad Ahmed, Sanjeev Khannaa

Abstract:

Glass fiber reinforced polymers are widely used in structural systems as load-bearing elements at both high and low temperatures. This investigation presents the evaluation of glass fiber reinforced unsaturated polyurethane under harsh conditions of changing temperature and moisture content. This study Explores how these parameters affect the optical properties of the polymer matrix and the composite. Using the hand layup method, the polyurethane resin was modified by E-glass fibers (15 vol. %) to manufacture fiber-reinforced composite. This work includes the preparation of glass-like polyurethane resin sheets and estimates all light transmittance properties at high and very low temperatures and wet conditions. All-optical properties were retested to evaluate the level of improvement or failure. The results found that when comprising reinforced composite fiber to the unreinforced specimens, the reinforced composite shows a fair optical property at high temperatures and good performance at low temperatures.

Keywords: unsaturated polyurethane, extreme temperatures, light transmittance, haze number

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1306 Skew Planar Wheel Antenna for First Person View of Unmanned Aerial Vehicle

Authors: Raymond Yudhi Purba, Levy Olivia Nur, Radial Anwar

Abstract:

This research presents the design and measurement of a skew planar wheel antenna that is used to visualize the first person view perspective of unmanned aerial vehicles. The antenna has been designed using CST Studio Suite 2019 to have voltage standing wave ratio (VSWR) ≤ 2, return loss ≤ -10 dB, bandwidth ≥ 100 MHz to covering outdoor access point band from 5.725 to 5.825 GHz, omnidirectional radiation pattern, and elliptical polarization. Dimensions of skew planar wheel antenna have been modified using parameter sweep technique to provide good performances. The simulation results provide VSWR 1.231, return loss -19.693 dB, bandwidth 828.8 MHz, gain 3.292 dB, and axial ratio 9.229 dB. Meanwhile, the measurement results provide VSWR 1.237, return loss -19.476 dB, bandwidth 790.5 MHz, gain 3.2034 dB, and axial ratio 4.12 dB.

Keywords: skew planar wheel, cloverleaf, first-person view, unmanned aerial vehicle, parameter sweep

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1305 In situ Polymerization and Properties of Biobased Polyurethane/Epoxy Interpenetrating Network Nanocomposites

Authors: Aiswarea Mathew, Smita Mohanty, Jr., S. K. Nayak

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Polyurethane networks based on castor oil (CO) as a renewable resource polyol were synthesized. Polyurethane/epoxy resin interpenetrating network nanocomposites containing modified montmorillonite organoclay (C30B-PU/EP nanocomposites) were prepared by an in situ intercalation method. The conventional spectroscopic characterization of the synthesized samples using FT-IR confirms the existence of the proposed castor oil based PU structure and also showed that strong interactions existed between C30B and EP/PU matrix. The dispersion degree of C30B in EP/PU matrix was characterized by X-Ray diffraction (XRD) method. Scanning electronic microscopy analysis showed that the interpenetrating process of PU and EP increases the exfoliation degree of C30B, and it improves the compatibility and the phase structure of polyurethane/epoxy resin interpenetrating polymer networks (PU/EP IPNs). The thermal stability improves compared to the polyurethane when the PU/EP IPN is formed. Mechanical properties including the Young’s modulus and tensile strength reflected marked improvement with addition of C30B.

Keywords: castor oil, epoxy, montmorillonite, polyurethane

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1304 Hydrodynamic Characterisation of a Hydraulic Flume with Sheared Flow

Authors: Daniel Rowe, Christopher R. Vogel, Richard H. J. Willden

Abstract:

The University of Oxford’s recirculating water flume is a combined wave and current test tank with a 1 m depth, 1.1 m width, and 10 m long working section, and is capable of flow speeds up to 1 ms−1 . This study documents the hydrodynamic characteristics of the facility in preparation for experimental testing of horizontal axis tidal stream turbine models. The turbine to be tested has a rotor diameter of 0.6 m and is a modified version of one of two model-scale turbines tested in previous experimental campaigns. An Acoustic Doppler Velocimeter (ADV) was used to measure the flow at high temporal resolution at various locations throughout the flume, enabling the spatial uniformity and turbulence flow parameters to be investigated. The mean velocity profiles exhibited high levels of spatial uniformity at the design speed of the flume, 0.6 ms−1 , with variations in the three-dimensional velocity components on the order of ±1% at the 95% confidence level, along with a modest streamwise acceleration through the measurement domain, a target 5 m working section of the flume. A high degree of uniformity was also apparent for the turbulence intensity, with values ranging between 1-2% across the intended swept area of the turbine rotor. The integral scales of turbulence exhibited a far higher degree of variation throughout the water column, particularly in the streamwise and vertical scales. This behaviour is believed to be due to the high signal noise content leading to decorrelation in the sampling records. To achieve more realistic levels of vertical velocity shear in the flume, a simple procedure to practically generate target vertical shear profiles in open-channel flows is described. Here, the authors arranged a series of non-uniformly spaced parallel bars placed across the width of the flume and normal to the onset flow. By adjusting the resistance grading across the height of the working section, the downstream profiles could be modified accordingly, characterised by changes in the velocity profile power law exponent, 1/n. Considering the significant temporal variation in a tidal channel, the choice of the exponent denominator, n = 6 and n = 9, effectively provides an achievable range around the much-cited value of n = 7 observed at many tidal sites. The resulting flow profiles, which we intend to use in future turbine tests, have been characterised in detail. The results indicate non-uniform vertical shear across the survey area and reveal substantial corner flows, arising from the differential shear between the target vertical and cross-stream shear profiles throughout the measurement domain. In vertically sheared flow, the rotor-equivalent turbulence intensity ranges between 3.0-3.8% throughout the measurement domain for both bar arrangements, while the streamwise integral length scale grows from a characteristic dimension on the order of the bar width, similar to the flow downstream of a turbulence-generating grid. The experimental tests are well-defined and repeatable and serve as a reference for other researchers who wish to undertake similar investigations.

Keywords: acoustic doppler Velocimeter, experimental hydrodynamics, open-channel flow, shear profiles, tidal stream turbines

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1303 Characterization of Mechanical Properties of Graphene-Modified Epoxy Resin for Pipeline Repair

Authors: Siti Nur Afifah Azraai, Lim Kar Sing, Nordin Yahaya, Norhazilan Md Noor

Abstract:

This experimental study consists of a characterization of epoxy grout where an amount of 2% of graphene nanoplatelets particles were added to commercial epoxy resin to evaluate their behavior regarding neat epoxy resin. Compressive tests, tensile tests and flexural tests were conducted to study the effect of graphene nanoplatelets on neat epoxy resin. By comparing graphene-based and neat epoxy grout, there is no significant increase of strength due to weak interface in the graphene nanoplatelets/epoxy composites. From this experiment, the tension and flexural strength of graphene-based epoxy grouts is slightly lower than ones of neat epoxy grout. Nevertheless, the addition of graphene has produced more consistent results according to a smaller standard deviation of strength. Furthermore, the graphene has also improved the ductility of the grout, hence reducing its brittle behaviour. This shows that the performance of graphene-based grout is reliably predictable and able to minimize sudden rupture. This is important since repair design of damaged pipeline is of deterministic nature.

Keywords: composite, epoxy resin, graphene nanoplatelets, pipeline

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1302 Microfluidization for Processing of Carbonized Chicken Feather Fiber (CCFF) Modified Epoxy Suspensions and the Thermal Properties of the Resulting Composites

Authors: A. Tuna, Y. Okumuş, A. T. Seyhan, H. Çelebi

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In this study, microfluidization was considered a promising approach to breaking up of carbonized chicken feather fibers (CCFFs) flocs to synthesizing epoxy suspensions containing (1 wt. %) CCFFs. For comparison, CCFF was also treated using sonication. The energy consumed to break up CCFFs in the ethanol was the same for both processes. CCFFs were found to be dispersed in ethanol in a significantly shorter time with the high shear processor. The CCFFs treated by both sonication and microfluidization were dispersed in epoxy by sonication. SEM examination revealed that CCFFs were broken up into smaller pieces using the high shear processor while being not agglomerated. Further, DSC, TMA, and DMA were systematically used to measure thermal properties of the resulting composites. A significant improvement was observed in the composites including CCFFs treated with microfluidization.

Keywords: carbonized chicken feather fiber (CCFF), modulated differential scanning calorimetry (MDSC), modulated thermomechanical analysis (MTMA), thermal properties

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1301 Effect of SCN5A Gene Mutation in Endocardial Cell

Authors: Helan Satish, M. Ramasubba Reddy

Abstract:

The simulation of an endocardial cell for gene mutation in the cardiac sodium ion channel NaV1.5, encoded by SCN5A gene, is discussed. The characterization of Brugada Syndrome by loss of function effect on SCN5A mutation due to L812Q mutant present in the DII-S4 transmembrane region of the NaV1.5 channel protein and its effect in an endocardial cell is studied. Ten Tusscher model of human ventricular action potential is modified to incorporate the changes contributed by L812Q mutant in the endocardial cells. Results show that BrS-associated SCN5A mutation causes reduction in the inward sodium current by modifications in the channel gating dynamics such as delayed activation, enhanced inactivation, and slowed recovery from inactivation in the endocardial cell. A decrease in the inward sodium current was also observed, which affects depolarization phase (Phase 0) that leads to reduction in the spike amplitude of the cardiac action potential.

Keywords: SCN5A gene mutation, sodium channel, Brugada syndrome, cardiac arrhythmia, action potential

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1300 Behavior of Helical Piles as Foundation of Photovoltaic Panels in Tropical Soils

Authors: Andrea J. Alarcón, Maxime Daulat, Raydel Lorenzo, Renato P. Da Cunha, Pierre Breul

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Brazil has increased the use of renewable energy during the last years. Due to its sunshine and large surface area, photovoltaic panels founded in helical piles have been used to produce solar energy. Since Brazilian territory is mainly cover by highly porous structured tropical soils, when the helical piles are installed this structure is broken and its soil properties are modified. Considering the special characteristics of these soils, helical foundations behavior must be extensively studied. The first objective of this work is to determine the most suitable method to estimate the tensile capacity of helical piles in tropical soils. The second objective is to simulate the behavior of these piles in tropical soil. To obtain the rupture to assess load-displacement curves and the ultimate load, also a numerical modelling using Plaxis software was conducted. Lastly, the ultimate load and the load-displacements curves are compared with experimental values to validate the implemented model.

Keywords: finite element, helical piles, modelling, tropical soil, uplift capacity

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1299 Evaluating the Suitability and Performance of Dynamic Modulus Predictive Models for North Dakota’s Asphalt Mixtures

Authors: Duncan Oteki, Andebut Yeneneh, Daba Gedafa, Nabil Suleiman

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Most agencies lack the equipment required to measure the dynamic modulus (|E*|) of asphalt mixtures, necessitating the need to use predictive models. This study compared measured |E*| values for nine North Dakota asphalt mixes using the original Witczak, modified Witczak, and Hirsch models. The influence of temperature on the |E*| models was investigated, and Pavement ME simulations were conducted using measured |E*| and predictions from the most accurate |E*| model. The results revealed that the original Witczak model yielded the lowest Se/Sy and highest R² values, indicating the lowest bias and highest accuracy, while the poorest overall performance was exhibited by the Hirsch model. Using predicted |E*| as inputs in the Pavement ME generated conservative distress predictions compared to using measured |E*|. The original Witczak model was recommended for predicting |E*| for low-reliability pavements in North Dakota.

Keywords: asphalt mixture, binder, dynamic modulus, MEPDG, pavement ME, performance, prediction

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1298 Synthesis and Application of Tamarind Hydroxypropane Sulphonic Acid Resin for Removal of Heavy Metal Ions from Industrial Wastewater

Authors: Aresh Vikram Singh, Sarika Nagar

Abstract:

The tamarind based resin containing hydroxypropane sulphonic acid groups has been synthesized and their adsorption behavior for heavy metal ions has been investigated using batch and column experiments. The hydroxypropane sulphonic acid group has been incorporated onto tamarind by a modified Porath's method of functionalisation of polysaccharides. The tamarind hydroxypropane sulphonic acid (THPSA) resin can selectively remove of heavy metal ions, which are contained in industrial wastewater. The THPSA resin was characterized by FTIR and thermogravimetric analysis. The effects of various adsorption conditions, such as pH, treatment time and adsorbent dose were also investigated. The optimum adsorption condition was found at pH 6, 120 minutes of equilibrium time and 0.1 gram of resin dose. The orders of distribution coefficient values were determined.

Keywords: distribution coefficient, industrial wastewater, polysaccharides, tamarind hydroxypropane sulphonic acid resin, thermogravimetric analysis, THPSA

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1297 Digital Dialogue Game, Epistemic Beliefs, Argumentation and Learning

Authors: Omid Noroozi, Martin Mulder

Abstract:

The motivational potential of educational games is undeniable especially for teaching topics and skills that are difficult to deal with in traditional educational situations such as argumentation competence. Willingness to argue has an association with student epistemic beliefs, which can influence whether, and the way in which students engage in argumentative discourse activities and critical discussion. The goal of this study was to explore how undergraduate students engage with argumentative discourse activities which have been designed to intensify debate, and whether epistemic beliefs are significant to the outcomes. A pre-test, post-test design was used with students who were assigned to groups of four. They were asked to argue a controversial topic with the aim of exploring various perspectives, and the 'pros and cons' on the topic of 'Genetically Modified Organisms (GMOs)'. The results show that the game facilitated argumentative discourse and a willingness to argue and challenged peers, regardless of students’ epistemic beliefs. Furthermore, the game was evaluated positively in terms of students’ motivation and satisfaction with the learning experience.

Keywords: argumentation, attitudinal change, epistemic beliefs, dialogue, digital game objectives and theoretical

Procedia PDF Downloads 393
1296 A Study on Impact of Corporate Social Responsibility on Rural Development

Authors: N. Amruth Raj, Suja S. Nair

Abstract:

The last six decades have borne witness to a radical change in the private sectors relationship with both the state and civil society. Firms have been increasingly called upon to adopt strategies beyond the financial aspects of their operations and consider the social and environmental impact of their business activities. In this context, many companies have modified their policies and activities and engaged into Corporate Social Responsibility (CSR) especially on Rural development in India. At the firm level, CSR is implemented through various practices, which aim to enhance the company’s social and environmental performance and may cover various topics. Examples of CSR practices are abundant in Andhra Pradesh relevant literature. For instance, in India especially at Andhra Pradesh companies like Amara Raaja requires from its suppliers to prohibit child labour, Nagarjuna Cements applies a series of programs for reducing its CO2 emissions, LANCO group of Industries addresses health and safety issues in the workplace whereas GVK works limited has adopted a series of policies for addressing human rights and environmental abuse related to its operations.

Keywords: CSR, limitations, need, objectives, rural development

Procedia PDF Downloads 239
1295 Adsorption of Iodine from Aqueous Solution on Modified Silica Gel with Cyclodextrin Derivatives

Authors: Raied, Badr Al-Fulaiti, E. I. El-Shafey

Abstract:

Cyclodextrin (CD) derivatives (αCD, βCD, ϒCD and hp-βCD) were successfully immobilized on silica gel surface via epichlorohydrin as a cross linker. The ratio of silica to CD was optimized in preliminary experiments based on best performance of iodine adsorption capacity. Selected adsorbents with ratios of silica to CD derivatives, in this study, include Si-αCD (3:2), Si-βCD (4:1), Si-ϒCD (4:1) and Si-hp-βCD (4:1). The adsorption of iodine (I2/KI) solution was investigated in terms of initial pH, contact time, iodine concentration and temperature. No significant variations was noticed for iodine adsorption at different pH values, thus, initial pH 6 was selected for further studies. Equilibrium adsorption was reached faster on Si-hp-βCD than other adsorbents with kinetic adsorption data fitting well pseudo second order model. Activation energy (Ea) was found to be in the range of 12.7 - 23.4 kJ/mol. Equilibrium adsorption data were found to fit well the Langmuir adsorption model with lower uptake as temperature rises. Iodine uptake follows the order: Si-hp-βCD (714 mg/g) >Si-αCD (625 mg/g) >Si-βCD (555.6 mg/g)> Si-ϒCD (435 mg/g). Thermodynamic study showed that iodine adsorption is exothermic and spontaneous. Adsorbents reuse exhibited excellent performance for iodine adsorption with a decrease in iodine uptake of ~ 2- 4 % in the third adsorption cycle.

Keywords: adsorption, iodine, silica, cyclodextrin, functionalization, epichlorohydrin

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1294 Causality, Special Relativity and Non-existence of Material Particles of Zero Rest Mass

Authors: Mohammad Saleem, Mujahid Kamran

Abstract:

It is shown that causality, the principle that cause must precede effect, leads inter alia, to highly significant result that the velocity of a material particle cannot be even equal to that of light. Consequently, combined with special relativity, it leads to the conclusion that material particles of zero rest mass cannot exist in nature. Thus, causality, a principle without which nature would be incomprehensible, combined with special relativity, forbids the existence of material particles of zero rest mass. For instance, the neutrinos, as is now known, are material particles of non-zero rest mass. The situation changes when we consider the gauge particles. In fact, when the principle of causality was proposed, the concept of gauge particles had not yet been introduced. Now we know that photon, a gauge particle with zero rest mass does exist in nature. Therefore, principle of causality, as generally stated, is valid only for material particles. For gauge particles, in order to make the statement of causality consistent with experiment, it has to be modified: The cause should either precede or be simultaneous with the effect. Combined with special relativity, it allows gauge particles of zero rest mass.

Keywords: causality, gauge particles, material particles, special relativity

Procedia PDF Downloads 478
1293 Dynamic Ad-hoc Topologies for Mobile Robot Navigation Based on Non-Uniform Grid Maps

Authors: Peter Sauer, Thomas Hinze, Petra Hofstedt

Abstract:

To avoid obstacles in the surrounding environment and to navigate to a given target belong to the most important tasks for mobile robots. According to these tasks different data structures are suitable. To avoid near obstacles, occupancy grid maps are an ideal representation of the surroundings. For less fine grained tasks, such as navigating from one room to another in an apartment, pure grid maps are inappropriate. Grid maps are very detailed, calculating paths to navigate between rooms based on grid maps would take too long. Instead, graph-based data structures, so-called topologies, turn out to be a proper choice for such tasks. In this paper we present two methods to dynamically create topologies from grid maps. Both methods are based on non-uniform grid maps. The topologies are generated on-the-fly and can easily be modified to represent changes in the environment. This allows a hybrid approach to control mobile robots, where, depending on the situation and the current task, either the grid map or the generated topology may be used.

Keywords: robot navigation, occupancy grids, topological maps, dynamic map creation

Procedia PDF Downloads 545
1292 Study of the Potential of Raw Sediments and Sediments Treated with Lime or Cement for Use in a Foundation Layer and the Base Layer of a Roadway

Authors: Nor-Edine Abriak, Mahfoud Benzerzour, Mouhamadou Amar, Abdeljalil Zri

Abstract:

In this work, firstly we have studied the potential of raw sediments and sediments treated with lime or cement for use in a foundation layer and the base layer of a roadway. Secondly, we have examined mineral changes caused by the addition of lime or cement in order to explain the mechanical performance of stabilized sediments. After determining the amount of lime and cement required stabilizing the sediments, the compaction characteristics and Immediate Bearing Capacity (IBI) were studied using the Modified Proctor method. Then, the evolution of the three parameters, which are optimum water content, maximum dry density and IBI, were determined. Mechanical performances can be evaluated through resistance to compression, resistance under traction and the elasticity modulus. The resistances of the formulations treated with ROLAC®645 increase with the amount of ROLAC®645. Traction resistance and the elastic modulus were used to evaluate the potential of the formulations as road construction materials using the classification diagram. The results show that all the other formulations with ROLAC®645 can be used in subgrades and foundation layers for roads.

Keywords: sediment, lime, cement, roadway

Procedia PDF Downloads 253