Search results for: loading factor performance
Commenced in January 2007
Frequency: Monthly
Edition: International
Paper Count: 17997

Search results for: loading factor performance

5607 Using of Particle Swarm Optimization for Loss Minimization of Vector-Controlled Induction Motors

Authors: V. Rashtchi, H. Bizhani, F. R. Tatari

Abstract:

This paper presents a new online loss minimization for an induction motor drive. Among the many loss minimization algorithms (LMAs) for an induction motor, a particle swarm optimization (PSO) has the advantages of fast response and high accuracy. However, the performance of the PSO and other optimization algorithms depend on the accuracy of the modeling of the motor drive and losses. In the development of the loss model, there is always a trade off between accuracy and complexity. This paper presents a new online optimization to determine an optimum flux level for the efficiency optimization of the vector-controlled induction motor drive. An induction motor (IM) model in d-q coordinates is referenced to the rotor magnetizing current. This transformation results in no leakage inductance on the rotor side, thus the decomposition into d-q components in the steady-state motor model can be utilized in deriving the motor loss model. The suggested algorithm is simple for implementation.

Keywords: induction machine, loss minimization, magnetizing current, particle swarm optimization

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5606 Effect of Concrete Waste Quality on the Compressive Strength of Recycled Concrete

Authors: Kebaili Bachir

Abstract:

The reuse of concrete waste as a secondary aggregate could be an efficient solution for sustainable development and long-term environmental protection. The variable nature of waste concrete, with various compressive strengths, can have a negative effect on the final compressive strength of recycled concrete. Accordingly, an experimental test programme was developed to evaluate the effect of parent concrete qualities on the performance of recycled concrete. Three grades with different compressive strengths 10MPa, 20MPa, and 30MPa were considered in the study; moreover, an unknown compressive strength was introduced as well. The trial mixes used 40% secondary aggregates (both course and fine) and 60% of natural aggregates. The compressive strength of the test concrete decrease between 15 and 25% compared to normal concrete with no secondary aggregates. This work proves that the strength properties of the parent concrete have a limited effect on the compressive strength of recycled concrete. Low compressive strength parent concrete when crushed generate a high percentage of recycled coarse aggregates with the less attached mortar and give the same compressive strength as an excellent parent concrete. However, the decrease in compressive strength can be mitigated by increasing the cement content 4% by weight of recycled aggregates used.

Keywords: compressive, concrete, quality, recycled, strength

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5605 Identifying Environmental Adaptive Genetic Loci in Caloteropis Procera (Estabragh): Population Genetics and Landscape Genetic Analyses

Authors: Masoud Sheidaei, Mohammad-Reza Kordasti, Fahimeh Koohdar

Abstract:

Calotropis procera (Aiton) W.T.Aiton, (Apocynaceae), is an economically and medicinally important plant species which is an evergreen, perennial shrub growing in arid and semi-arid climates, and can tolerate very low annual rainfall (150 mm) and a dry season. The plant can also tolerate temperature ran off 20 to30°C and is not frost tolerant. This plant species prefers free-draining sandy soils but can grow also in alkaline and saline soils.It is found at a range of altitudes from exposed coastal sites to medium elevations up to 1300 m. Due to morpho-physiological adaptations of C. procera and its ability to tolerate various abiotic stresses. This taxa can compete with desirable pasture species and forms dense thickets that interfere with stock management, particularly mustering activities. Caloteropis procera grows only in southern part of Iran where in comprises a limited number of geographical populations. We used different population genetics and r landscape analysis to produce data on geographical populations of C. procera based on molecular genetic study using SCoT molecular markers. First, we used spatial principal components (sPCA), as it can analyze data in a reduced space and can be used for co-dominant markers as well as presence / absence data as is the case in SCoT molecular markers. This method also carries out Moran I and Mantel tests to reveal spatial autocorrelation and test for the occurrence of Isolation by distance (IBD). We also performed Random Forest analysis to identify the importance of spatial and geographical variables on genetic diversity. Moreover, we used both RDA (Redundency analysis), and LFMM (Latent factor mixed model), to identify the genetic loci significantly associated with geographical variables. A niche modellng analysis was carried our to predict present potential area for distribution of these plants and also the area present by the year 2050. The results obtained will be discussed in this paper.

Keywords: population genetics, landscape genetic, Calotreropis procera, niche modeling, SCoT markers

Procedia PDF Downloads 83
5604 The Effect of Peripheral Fatigue and Visual Feedback on Postural Control and Strength in Obese People

Authors: Elham Azimzadeh, Saeedeh Sepehri, Hamidollah Hassanlouei

Abstract:

Obesity is associated with postural instability, might influence the quality of daily life, and could be considered a potential factor for falling in obese people. The fat body mass especially in the abdominal area may increase body sway. Furthermore, loss of visual feedback may induce a larger postural sway in obese people. Moreover, Muscle fatigue may impair the work capacity of the skeletal muscle and may alter joint proprioception. So, the purpose of this study was to investigate the effect of physical fatigue and visual feedback on body sway and strength of lower extremities in obese people. 12 obese (4 female, 8 male; BMI >30 kg/m2), and 12 normal weight (4 female, 8 male; BMI: 20-25 kg/m2) subjects aged 37- 47 years participated in this study. The postural stability test on the Biodex balance system was used to characterize postural control along the anterior-posterior (AP) and mediolateral (ML) directions in eyes open and eyes closed conditions and maximal voluntary contraction (MVC) of knee extensors and flexors were measured before and after the high-intensity exhausting exercise protocol on the ergometer bike to confirm the presence of fatigue. Results indicated that the obese group demonstrated significantly greater body sway, in all indices (ML, AP, overall) compared with the normal weight group (eyes open). However, when visual feedback was eliminated, fatigue impaired the balance in the overall and AP indicators in both groups; ML sway was higher only in the obese group after exerting the fatigue in the eyes closed condition. Also, maximal voluntary contraction of knee extensors was impaired in the fatigued normal group but, there was no significant impairment in knee flexors MVC in both group. According to the findings, peripheral fatigue was associated with altered postural control in upright standing when eyes were closed, and that mechanoreceptors of the feet may be less able to estimate the position of the body COM over the base of support in the loss of visual feedback. This suggests that the overall capability of the postural control system during upright standing especially in the ML direction could be lower due to fatigue in obese individuals and could be a predictor of future falls.

Keywords: maximal voluntary contraction, obesity, peripheral fatigue, postural control, visual feedback

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5603 Energy Analysis of an Ejector Based Solar Assisted Trigeneration System for Dairy Application

Authors: V. Ravindra, P. A. Saikiran, M. Ramgopal

Abstract:

This paper presents an energy analysis of a solar assisted trigeneration system using an Ejector for dairy applications. The working fluid in the trigeneration loop is Supercritical CO₂. The trigeneration system is a combination of Brayton cycle and ejector based vapor compression refrigeration cycle. The heating and cooling outputs are used for simultaneous pasteurization and chilling of the milk. The electrical power is used to drive the auxiliary equipment in the dairy plant. A numerical simulation is done with Engineering Equation Solver (EES), and a parametric analysis is performed by varying the operating variables over a meaningful range. The results show that the overall performance index decreases with increase in ambient temperature. For an ejector based system, the compressor work and cooling output are significant output quantities. An increase in total mass flow rate of the refrigerant (primary + secondary) results in an increase in the compressor work and cooling output.

Keywords: trigeneration, solar thermal, supercritical CO₂, ejector

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5602 Shear Strengthening of Reinforced Concrete Deep Beams Using Carbon Fiber Reinforced Polymers

Authors: Hana' Al-Ghanim, Mu'tasim Abdel-Jaber, Maha Alqam

Abstract:

This experimental investigation deals with shear strengthening of reinforced concrete (RC) deep beams using the externally bonded carbon fiber-reinforced polymer (CFRP) composites. The current study, therefore, evaluates the effectiveness of four various configurations for shear strengthening of deep beams with two different types of CFRP materials including sheets and laminates. For this purpose, a total of 10 specimens of deep beams were cast and tested. The shear performance of the strengthened beams is assessed with respect to the cracks’ formation, modes of failure, ultimate strength and the overall stiffness. The obtained results demonstrate the effectiveness of using the CFRP technique on enhancing the shear capacity of deep beams; however, the efficiency varies depending on the material used and the strengthening scheme adopted. Among the four investigated schemes, the highest increase in the ultimate strength is recorded by using the continuous wrap of two layers of CFRP sheets, exceeding a value of 86%, whereas an enhancement of about 36% is achieved by the inclined CFRP laminates.

Keywords: deep beams, laminates, shear strengthening, sheets

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5601 Numerical Modelling of Wind Dispersal Seeds of Bromeliad Tillandsia recurvata L. (L.) Attached to Electric Power Lines

Authors: Bruna P. De Souza, Ricardo C. De Almeida

Abstract:

In some cities in the State of Parana – Brazil and in other countries atmospheric bromeliads (Tillandsia spp - Bromeliaceae) are considered weeds in trees, electric power lines, satellite dishes and other artificial supports. In this study, a numerical model was developed to simulate the seed dispersal of the Tillandsia recurvata species by wind with the objective of evaluating seeds displacement in the city of Ponta Grossa – PR, Brazil, since it is considered that the region is already infested. The model simulates the dispersal of each individual seed integrating parameters from the atmospheric boundary layer (ABL) and the local wind, simulated by the Weather Research Forecasting (WRF) mesoscale atmospheric model for the 2012 to 2015 period. The dispersal model also incorporates the approximate number of bromeliads and source height data collected from most infested electric power lines. The seeds terminal velocity, which is an important input data but was not available in the literature, was measured by an experiment with fifty-one seeds of Tillandsia recurvata. Wind is the main dispersal agent acting on plumed seeds whereas atmospheric turbulence is a determinant factor to transport the seeds to distances beyond 200 meters as well as to introduce random variability in the seed dispersal process. Such variability was added to the model through the application of an Inverse Fast Fourier Transform to wind velocity components energy spectra based on boundary-layer meteorology theory and estimated from micrometeorological parameters produced by the WRF model. Seasonal and annual wind means were obtained from the surface wind data simulated by WRF for Ponta Grossa. The mean wind direction is assumed to be the most probable direction of bromeliad seed trajectory. Moreover, the atmospheric turbulence effect and dispersal distances were analyzed in order to identify likely regions of infestation around Ponta Grossa urban area. It is important to mention that this model could be applied to any species and local as long as seed’s biological data and meteorological data for the region of interest are available.

Keywords: atmospheric turbulence, bromeliad, numerical model, seed dispersal, terminal velocity, wind

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5600 Knowledge Management Challenges within Traditional Procurement System

Authors: M. Takhtravanchi, C. Pathirage

Abstract:

In the construction industry, project members are conveyor of project knowledge which is, often, not managed properly to be used in future projects. As construction projects are temporary and unique, project members are willing to be recruited once a project is completed. Therefore, poor management of knowledge across construction projects will lead to a considerable amount of knowledge loss; the ignoring of which would be detrimental to project performance. This issue is more prominent in projects undertaken through the traditional procurement system, as this system does not incentives project members for integration. Thus, disputes exist between the design and construction phases based on the poor management of knowledge between those two phases. This paper aims to highlight the challenges of the knowledge management that exists within the traditional procurement system. Expert interviews were conducted and challenges were identified and analysed by the Interpretive Structural Modelling (ISM) approach in order to summarise the relationships among them. Two identified key challenges are the Culture of an Organisation and Knowledge Management Policies. A knowledge of the challenges and their relationships will help project manager and stakeholders to have a better understanding of the importance of knowledge management.

Keywords: challenges, construction industry, knowledge management, traditional procurement system

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5599 Bias Optimization of Mach-Zehnder Modulator Considering RF Gain on OFDM Radio-Over-Fiber System

Authors: Ghazi Al Sukkar, Yazid Khattabi, Shifen Zhong

Abstract:

Most of the recent wireless LANs, broadband access networks, and digital broadcasting use Orthogonal Frequency Division Multiplexing techniques. In addition, the increasing demand of Data and Internet makes fiber optics an important technology, as fiber optics has many characteristics that make it the best solution for transferring huge frames of Data from a point to another. Radio over fiber is the place where high quality RF is converted to optical signals over single mode fiber. Optimum values for the bias level and the switching voltage for Mach-Zehnder modulator are important for the performance of radio over fiber links. In this paper, we propose a method to optimize the two parameters simultaneously; the bias and the switching voltage point of the external modulator of a radio over fiber system considering RF gain. Simulation results show the optimum gain value under these two parameters.

Keywords: OFDM, Mach Zehnder bias voltage, switching voltage, radio-over-fiber, RF gain

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5598 Where do Pregnant Women Miss Out on Nutrition? Analysis of Survey Data from 22 Countries

Authors: Alexis D'Agostino, Celeste Sununtunasuk, Jack Fiedler

Abstract:

Background: Iron-folic acid (IFA) supplementation during antenatal care (ANC) has existed in many countries for decades. Despite this, low national coverage persists and women do not often consume appropriate amounts during pregnancy. USAID’s SPRING Project investigated pregnant women’s access to, and consumption of, IFA tablets through ANC. Cross-country analysis provided a global picture of the state of IFA-supplementation, while country-specific results noted key contextual issues, including geography, wealth, and ANC attendance. The analysis can help countries prioritize strategies for systematic performance improvements within one of the most common micronutrient supplementation programs aimed at reducing maternal anemia. Methodology: Using falter point analysis on Demographic and Health Survey (DHS) data collected from 162,958 women across 22 countries, SPRING identified four sequential falter points (ANC attendance, IFA receipt or purchase, IFA consumption, and number of tablets taken) where pregnant women fell out of the IFA distribution structure. SPRING analyzed data on IFA intake from DHS surveys with women of reproductive age. SPRING disaggregated these data by ANC participation during the most recent pregnancy, residency, and women’s socio-economic status. Results: Average sufficient IFA tablet use across all countries was only eight percent. Even in the best performing countries, only about one-third of pregnant women consumed 180 or more IFA tablets during their most recent pregnancy. ANC attendance was an important falter point for a quarter of women across all countries (with highest falter rates in Democratic Republic of the Congo, Nigeria, and Niger). Further analysis reveals patterns, with some countries having high ANC coverage but low IFA provision during ANC (DRC and Haiti), others having high ANC coverage and IFA provision but few women taking any tablets (Nigeria and Liberia), and countries that perform well in ANC, supplies, and initial consumption but where very few women consume the recommended 180 tablets (Malawi and Cambodia). Country-level analysis identifies further patterns of supplementation. In Indonesia, for example, only 62% of women in the poorest quintile took even one IFA tablet, while 86% of the wealthiest women did. This association between socioeconomic status and IFA intake held across nearly all countries where these data are available and was also visible in rural/urban comparisons. Analysis of ANC attendance data also suggests that higher numbers of ANC visits are associated with higher tablet intake. Conclusions: While it is difficult to disentangle which specific aspects of supply or demand cause the low rates of consumption, this tool allows policy-makers to identify major bottlenecks to scaling-up IFA supplementation during ANC. In turn, each falter point provides possible explanations of program performance and helps strategically identify areas for improved IFA supplementation. For example, improving the delivery of IFA supplementation in Ethiopia relies on increasing access to ANC, but also on identifying and addressing program gaps in IFA supply management and health workers’ practices in order to provide quality ANC services. While every country requires a customized approach to improving IFA supplementation, the multi-country analysis conducted by SPRING is a helpful first step in identifying country bottlenecks and prioritizing interventions.

Keywords: iron and folic acid, supplementation, antenatal care, micronutrient

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5597 A Sense of Belonging: Music Learning and School Connectedness

Authors: Johanna Gamboa-Kroesen

Abstract:

School connectedness, or the sense of belonging at school, is a critical factor in adolescent health, academic achievement, and socioemotional well-being. In educational research, the construct of the psychological sense of school membership is often referred to as school engagement, school bonding, or school attachment. While current research recognizes school connectedness as integral to a child’s mental health and academic success, many schools have yet to develop adequate interventions to promote a child’s overall sense of belonging at school. However, prior researches in music education indicates that, among other benefits, music classrooms may provide an environment where students feel they belong. While studies indicates that music learning environments, specifically performing ensemble learning environments, instill a sense of school connectedness and, more broadly, contribute to a student’s socio-emotional development, there has been inadequate research on how the actions of music teachers contribute to this phenomenon. The purpose of this study was to examine the relationship between school connectedness and music learning environments with middle school music students enrolled in a school-based music ensemble. In addition, the study aimed to provide a descriptive analysis of the instructional practices that music teachers use to promote an inclusive environment in their classrooms and an overall sense of belonging in their students. Using 191 student surveys of school membership, student reflective writings, 5 teacher interviews, and 10 classroom observations, this study examined the relationship between 7th and 8th-grade student-reported levels of connectedness within their school-based music ensemble and teacher instructional practice. The study found that students reported high levels of positive school membership within their music classes. Students who participate in school-based orchestra ensembles reported a positive change in emotional state during music instruction. In addition, evidence in this study found that music teachers use instructional practices to build connectedness through de-emphasizing competition and strengthening a student’s sense of relational value within their music learning experience. The findings offer implications for future music teacher instruction to create environments of inclusion, strengthen student-teacher relationships, and promote strategies that enhance student connection to school.

Keywords: music education, belonging, instructional practice, school connectedness

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5596 Automation of Finite Element Simulations for the Design Space Exploration and Optimization of Type IV Pressure Vessel

Authors: Weili Jiang, Simon Cadavid Lopera, Klaus Drechsler

Abstract:

Fuel cell vehicle has become the most competitive solution for the transportation sector in the hydrogen economy. Type IV pressure vessel is currently the most popular and widely developed technology for the on-board storage, based on their high reliability and relatively low cost. Due to the stringent requirement on mechanical performance, the pressure vessel is subject to great amount of composite material, a major cost driver for the hydrogen tanks. Evidently, the optimization of composite layup design shows great potential in reducing the overall material usage, yet requires comprehensive understanding on underlying mechanisms as well as the influence of different design parameters on mechanical performance. Given the type of materials and manufacturing processes by which the type IV pressure vessels are manufactured, the design and optimization are a nuanced subject. The manifold of stacking sequence and fiber orientation variation possibilities have an out-standing effect on vessel strength due to the anisotropic property of carbon fiber composites, which make the design space high dimensional. Each variation of design parameters requires computational resources. Using finite element analysis to evaluate different designs is the most common method, however, the model-ing, setup and simulation process can be very time consuming and result in high computational cost. For this reason, it is necessary to build a reliable automation scheme to set up and analyze the di-verse composite layups. In this research, the simulation process of different tank designs regarding various parameters is conducted and automatized in a commercial finite element analysis framework Abaqus. Worth mentioning, the modeling of the composite overwrap is automatically generated using an Abaqus-Python scripting interface. The prediction of the winding angle of each layer and corresponding thickness variation on dome region is the most crucial step of the modeling, which is calculated and implemented using analytical methods. Subsequently, these different composites layups are simulated as axisymmetric models to facilitate the computational complexity and reduce the calculation time. Finally, the results are evaluated and compared regarding the ultimate tank strength. By automatically modeling, evaluating and comparing various composites layups, this system is applicable for the optimization of the tanks structures. As mentioned above, the mechanical property of the pressure vessel is highly dependent on composites layup, which requires big amount of simulations. Consequently, to automatize the simulation process gains a rapid way to compare the various designs and provide an indication of the optimum one. Moreover, this automation process can also be operated for creating a data bank of layups and corresponding mechanical properties with few preliminary configuration steps for the further case analysis. Subsequently, using e.g. machine learning to gather the optimum by the data pool directly without the simulation process.

Keywords: type IV pressure vessels, carbon composites, finite element analy-sis, automation of simulation process

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5595 Surface Enhanced Infrared Absorption for Detection of Ultra Trace of 3,4- Methylene Dioxy- Methamphetamine (MDMA)

Authors: Sultan Ben Jaber

Abstract:

Optical properties of molecules exhibit dramatic changes when adsorbed close to nano-structure metallic surfaces such as gold and silver nanomaterial. This phenomena opened a wide range of research to improve conventional spectroscopies efficiency. A well-known technique that has an intensive focus of study is surface-enhanced Raman spectroscopy (SERS), as since the first observation of SERS phenomena, researchers have published a great number of articles about the potential mechanisms behind this effect as well as developing materials to maximize the enhancement. Infrared and Raman spectroscopy are complementary techniques; thus, surface-enhanced infrared absorption (SEIRA) also shows a noticeable enhancement of molecules in the mid-IR excitation on nonmetallic structure substrates. In the SEIRA, vibrational modes that gave change in dipole moments perpendicular to the nano-metallic substrate enhanced 200 times greater than the free molecule’s modes. SEIRA spectroscopy is promising for the characterization and identification of adsorbed molecules on metallic surfaces, especially at trace levels. IR reflection-absorption spectroscopy (IRAS) is a well-known technique for measuring IR spectra of adsorbed molecules on metallic surfaces. However, SEIRA spectroscopy sensitivity is up to 50 times higher than IRAS. SEIRA enhancement has been observed for a wide range of molecules adsorbed on metallic substrates such as Au, Ag, Pd, Pt, Al, and Ni, but Au and Ag substrates exhibited the highest enhancement among the other mentioned substrates. In this work, trace levels of 3,4-methylenedioxymethamphetamine (MDMA) have been detected using gold nanoparticles (AuNPs) substrates with surface-enhanced infrared absorption (SEIRA). AuNPs were first prepared and washed, then mixed with different concentrations of MDMA samples. The process of fabricating the substrate prior SEIRA measurements included mixing of AuNPs and MDMA samples followed by vigorous stirring. The stirring step is particularly crucial, as stirring allows molecules to be robustly adsorbed on AuNPs. Thus, remarkable SEIRA was observed for MDMA samples even at trace levels, showing the rigidity of our approach to preparing SEIRA substrates.

Keywords: surface-enhanced infrared absorption (SEIRA), gold nanoparticles (AuNPs), amphetamines, methylene dioxy- methamphetamine (MDMA), enhancement factor

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5594 Mathematical Study of CO₂ Dispersion in Carbonated Water Injection Enhanced Oil Recovery Using Non-Equilibrium 2D Simulator

Authors: Ahmed Abdulrahman, Jalal Foroozesh

Abstract:

CO₂ based enhanced oil recovery (EOR) techniques have gained massive attention from major oil firms since they resolve the industry's two main concerns of CO₂ contribution to the greenhouse effect and the declined oil production. Carbonated water injection (CWI) is a promising EOR technique that promotes safe and economic CO₂ storage; moreover, it mitigates the pitfalls of CO₂ injection, which include low sweep efficiency, early CO₂ breakthrough, and the risk of CO₂ leakage in fractured formations. One of the main challenges that hinder the wide adoption of this EOR technique is the complexity of accurate modeling of the kinetics of CO₂ mass transfer. The mechanisms of CO₂ mass transfer during CWI include the slow and gradual cross-phase CO₂ diffusion from carbonated water (CW) to the oil phase and the CO₂ dispersion (within phase diffusion and mechanical mixing), which affects the oil physical properties and the spatial spreading of CO₂ inside the reservoir. A 2D non-equilibrium compositional simulator has been developed using a fully implicit finite difference approximation. The material balance term (k) was added to the governing equation to account for the slow cross-phase diffusion of CO₂ from CW to the oil within the gird cell. Also, longitudinal and transverse dispersion coefficients have been added to account for CO₂ spatial distribution inside the oil phase. The CO₂-oil diffusion coefficient was calculated using the Sigmund correlation, while a scale-dependent dispersivity was used to calculate CO₂ mechanical mixing. It was found that the CO₂-oil diffusion mechanism has a minor impact on oil recovery, but it tends to increase the amount of CO₂ stored inside the formation and slightly alters the residual oil properties. On the other hand, the mechanical mixing mechanism has a huge impact on CO₂ spatial spreading (accurate prediction of CO₂ production) and the noticeable change in oil physical properties tends to increase the recovery factor. A sensitivity analysis has been done to investigate the effect of formation heterogeneity (porosity, permeability) and injection rate, it was found that the formation heterogeneity tends to increase CO₂ dispersion coefficients, and a low injection rate should be implemented during CWI.

Keywords: CO₂ mass transfer, carbonated water injection, CO₂ dispersion, CO₂ diffusion, cross phase CO₂ diffusion, within phase CO2 diffusion, CO₂ mechanical mixing, non-equilibrium simulation

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5593 Investigation of the Unbiased Characteristic of Doppler Frequency to Different Antenna Array Geometries

Authors: Somayeh Komeylian

Abstract:

Array signal processing techniques have been recently developing in a variety application of the performance enhancement of receivers by refraining the power of jamming and interference signals. In this scenario, biases induced to the antenna array receiver degrade significantly the accurate estimation of the carrier phase. Owing to the integration of frequency becomes the carrier phase, we have obtained the unbiased doppler frequency for the high precision estimation of carrier phase. The unbiased characteristic of Doppler frequency to the power jamming and the other interference signals allows achieving the highly accurate estimation of phase carrier. In this study, we have rigorously investigated the unbiased characteristic of Doppler frequency to the variation of the antenna array geometries. The simulation results have efficiently verified that the Doppler frequency remains also unbiased and accurate to the variation of antenna array geometries.

Keywords: array signal processing, unbiased doppler frequency, GNSS, carrier phase, and slowly fluctuating point target

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5592 The Effects of the GAA15 (Gaelic Athletic Association 15) on Lower Extremity Injury Incidence and Neuromuscular Functional Outcomes in Collegiate Gaelic Games: A 2 Year Prospective Study

Authors: Brenagh E. Schlingermann, Clare Lodge, Paula Rankin

Abstract:

Background: Gaelic football, hurling and camogie are highly popular field games in Ireland. Research into the epidemiology of injury in Gaelic games revealed that approximately three quarters of the injuries in the games occur in the lower extremity. These injuries can have player, team and institutional impacts due to multiple factors including financial burden and time loss from competition. Research has shown it is possible to record injury data consistently with the GAA through a closed online recording system known as the GAA injury surveillance database. It has been established that determining the incidence of injury is the first step of injury prevention. The goals of this study were to create a dynamic GAA15 injury prevention programme which addressed five key components/goals; avoid positions associated with a high risk of injury, enhance flexibility, enhance strength, optimize plyometrics and address sports specific agilities. These key components are internationally recognized through the Prevent Injury, Enhance performance (PEP) programme which has proven reductions in ACL injuries by 74%. In national Gaelic games the programme is known as the GAA15 which has been devised from the principles of the PEP. No such injury prevention strategies have been published on this cohort in Gaelic games to date. This study will investigate the effects of the GAA15 on injury incidence and neuromuscular function in Gaelic games. Methods: A total of 154 players (mean age 20.32 ± 2.84) were recruited from the GAA teams within the Institute of Technology Carlow (ITC). Preseason and post season testing involved two objective screening tests; Y balance test and Three Hop Test. Practical workshops, with ongoing liaison, were provided to the coaches on the implementation of the GAA15. The programme was performed before every training session and game and the existing GAA injury surveillance database was accessed to monitor player’s injuries by the college sports rehabilitation athletic therapist. Retrospective analysis of the ITC clinic records were performed in conjunction with the database analysis as a means of tracking injuries that may have been missed. The effects of the programme were analysed by comparing the intervention groups Y balance and three hop test scores to an age/gender matched control group. Results: Year 1 results revealed significant increases in neuromuscular function as a result of the GAA15. Y Balance test scores for the intervention group increased in both the posterolateral (p=.005 and p=.001) and posteromedial reach directions (p= .001 and p=.001). A decrease in performance was determined for the three hop test (p=.039). Overall twenty-five injuries were reported during the season resulting in an injury rate of 3.00 injuries/1000hrs of participation; 1.25 injuries/1000hrs training and 4.25 injuries/1000hrs match play. Non-contact injuries accounted for 40% of the injuries sustained. Year 2 results are pending and expected April 2016. Conclusion: It is envisaged that implementation of the GAA15 will continue to reduce the risk of injury and improve neuromuscular function in collegiate Gaelic games athletes.

Keywords: GAA15, Gaelic games, injury prevention, neuromuscular training

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5591 Numerical Analysis of the Flow Characteristics Around a Deformable Vortex Generator

Authors: Aimad Koulali

Abstract:

Flow structure evolution around a single pair of Delta vortex generators (VGs) is studied numerically. For laminar, transient, and turbulent flow regimes, numerical simulations have been performed in a duct with a pair of Delta vortex generators. The finiteelementmethodwasused to simulate the flow. To formulate the fluid structure interaction problem, the ALE formulation was used. The aim of this study is to provide a detailed insight into the generation and dissipation of longitudinal vortices over a wide range of flow regimes, including the laminar-turbulent transition. A wide range of parameters has been exploited to describe the inducedphenomenawithin the flow. Weexaminedvariousparametersdepending on the VG geometry, the flow regime, and the channel geometry. A detailed analysis of the turbulence and wall shear stress properties has been evaluated. The results affirm that there are still optimal values to obtain better performing vortices in order to improve the exchange performance.

Keywords: finte element method, deformable vortex generator, numerical analysis, fluid structure interaction, ALE formlation, turbulent flow

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5590 Computer-Aided Teaching of Transformers for Undergraduates

Authors: Rajesh Kumar, Roopali Dogra, Puneet Aggarwal

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In the era of technological advancement, use of computer technology has become inevitable. Hence it has become the need of the hour to integrate software methods in engineering curriculum as a part to boost pedagogy techniques. Simulations software is a great help to graduates of disciplines such as electrical engineering. Since electrical engineering deals with high voltages and heavy instruments, extra care must be taken while operating with them. The viable solution would be to have appropriate control. The appropriate control could be well designed if engineers have knowledge of kind of waveforms associated with the system. Though these waveforms can be plotted manually, but it consumes a lot of time. Hence aid of simulation helps to understand steady state of system and resulting in better performance. In this paper computer, aided teaching of transformer is carried out using MATLAB/Simulink. The test carried out on a transformer includes open circuit test and short circuit respectively. The respective parameters of transformer are then calculated using the values obtained from open circuit and short circuit test respectively using Simulink.

Keywords: computer aided teaching, open circuit test, short circuit test, simulink, transformer

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5589 Development and Validation of an Instrument Measuring the Coping Strategies in Situations of Stress

Authors: Lucie Côté, Martin Lauzier, Guy Beauchamp, France Guertin

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Stress causes deleterious effects to the physical, psychological and organizational levels, which highlight the need to use effective coping strategies to deal with it. Several coping models exist, but they don’t integrate the different strategies in a coherent way nor do they take into account the new research on the emotional coping and acceptance of the stressful situation. To fill these gaps, an integrative model incorporating the main coping strategies was developed. This model arises from the review of the scientific literature on coping and from a qualitative study carried out among workers with low or high levels of stress, as well as from an analysis of clinical cases. The model allows one to understand under what circumstances the strategies are effective or ineffective and to learn how one might use them more wisely. It includes Specific Strategies in controllable situations (the Modification of the Situation and the Resignation-Disempowerment), Specific Strategies in non-controllable situations (Acceptance and Stubborn Relentlessness) as well as so-called General Strategies (Wellbeing and Avoidance). This study is intended to undertake and present the process of development and validation of an instrument to measure coping strategies based on this model. An initial pool of items has been generated from the conceptual definitions and three expert judges have validated the content. Of these, 18 items have been selected for a short form questionnaire. A sample of 300 students and employees from a Quebec university was used for the validation of the questionnaire. Concerning the reliability of the instrument, the indices observed following the inter-rater agreement (Krippendorff’s alpha) and the calculation of the coefficients for internal consistency (Cronbach's alpha) are satisfactory. To evaluate the construct validity, a confirmatory factor analysis using MPlus supports the existence of a model with six factors. The results of this analysis suggest also that this configuration is superior to other alternative models. The correlations show that the factors are only loosely related to each other. Overall, the analyses carried out suggest that the instrument has good psychometric qualities and demonstrates the relevance of further work to establish predictive validity and reconfirm its structure. This instrument will help researchers and clinicians better understand and assess coping strategies to cope with stress and thus prevent mental health issues.

Keywords: acceptance, coping strategies, stress, validation process

Procedia PDF Downloads 331
5588 Multi-Classification Deep Learning Model for Diagnosing Different Chest Diseases

Authors: Bandhan Dey, Muhsina Bintoon Yiasha, Gulam Sulaman Choudhury

Abstract:

Chest disease is one of the most problematic ailments in our regular life. There are many known chest diseases out there. Diagnosing them correctly plays a vital role in the process of treatment. There are many methods available explicitly developed for different chest diseases. But the most common approach for diagnosing these diseases is through X-ray. In this paper, we proposed a multi-classification deep learning model for diagnosing COVID-19, lung cancer, pneumonia, tuberculosis, and atelectasis from chest X-rays. In the present work, we used the transfer learning method for better accuracy and fast training phase. The performance of three architectures is considered: InceptionV3, VGG-16, and VGG-19. We evaluated these deep learning architectures using public digital chest x-ray datasets with six classes (i.e., COVID-19, lung cancer, pneumonia, tuberculosis, atelectasis, and normal). The experiments are conducted on six-classification, and we found that VGG16 outperforms other proposed models with an accuracy of 95%.

Keywords: deep learning, image classification, X-ray images, Tensorflow, Keras, chest diseases, convolutional neural networks, multi-classification

Procedia PDF Downloads 77
5587 A Consideration of Dialectal and Stylistic Shifts in Literary Translation

Authors: Pushpinder Syal

Abstract:

Literary writing carries the stamp of the current language of its time. In translating such texts, it becomes a challenge to capture such reflections which may be evident at several levels: the level of dialectal use of language by characters in stories, the alterations in syntax as tools of writers’ individual stylistic choices, the insertion of quasi-proverbial and gnomic utterances, and even the level of the pragmatics of narrative discourse. Discourse strategies may differ between earlier and later texts, reflecting changing relationships between narrators and readers in changed cultural and social contexts. This paper is a consideration of these features by an approach that combines historicity with a description, contextualizing language change within a discourse framework. The process of translating a collection of writings of Punjabi literature spanning 100 years was undertaken for this study and it was observed that the factor of the historicity of language was seen to play a role. While intended for contemporary readers, the translation of literature over the span of a century poses the dual challenge of needing to possess both accessibility and immediacy as well as adherence to the 'old world' styles of communicating and narrating. The linguistic changes may be observed in a more obvious sense in the difference of diction and word formation – with evidence of more hybridized and borrowed forms in modern and contemporary writings, as compared to the older writings. The latter not only contain vestiges of proverbs and folk sayings, but are also closer to oral speech styles. These will be presented and analysed in the form of chronological listing and by these means, the social process of translation from orality to written text can be seen as traceable in the above-mentioned works. More subtle and underlying shifts can be seen through the analysis of speech acts and implicatures in the same literature, in which the social relationships underlying language use are evident as discourse systems of belief and understanding. They present distinct shifts in worldview as seen at different points in time. However, some continuities of language and style are also clearly visible, and these aid the translator in putting together a set of thematic links which identify the literature of a region and community, and constitute essential outcomes in the effort to preserve its distinctive nature.

Keywords: cultural change, dialect, historicity, stylistic variation

Procedia PDF Downloads 122
5586 Performance of Neural Networks vs. Radial Basis Functions When Forming a Metamodel for Residential Buildings

Authors: Philip Symonds, Jon Taylor, Zaid Chalabi, Michael Davies

Abstract:

With the world climate projected to warm and major cities in developing countries becoming increasingly populated and polluted, governments are tasked with the problem of overheating and air quality in residential buildings. This paper presents the development of an adaptable model of these risks. Simulations are performed using the EnergyPlus building physics software. An accurate metamodel is formed by randomly sampling building input parameters and training on the outputs of EnergyPlus simulations. Metamodels are used to vastly reduce the amount of computation time required when performing optimisation and sensitivity analyses. Neural Networks (NNs) are compared to a Radial Basis Function (RBF) algorithm when forming a metamodel. These techniques were implemented using the PyBrain and scikit-learn python libraries, respectively. NNs are shown to perform around 15% better than RBFs when estimating overheating and air pollution metrics modelled by EnergyPlus.

Keywords: neural networks, radial basis functions, metamodelling, python machine learning libraries

Procedia PDF Downloads 433
5585 Liquidity and Cash Management Practices of Owner-Managed Firms-A Case of South East, Nigeria

Authors: Ugbor Raphael Oluchukwu

Abstract:

The survey research design was adopted to examine whether liquidity and cash management practices of owner-managed firms in South East Nigeria influence their profitability, growth and survival. Four independent variables (accounting systems, working capital management, budgetary control, and managerial planning) were used in the evaluation which was restricted to eight small firms. Results indicate that one variable, working capital management alone dominate the liquidity perception of owner managers. As a result, owner managers find it difficult to meet maturing business obligations as growth sets in. The study also reveals that the four independent variables have significant impact on the profitability, growth and survival of owner managed firms. Owner managers are therefore advised to undertake regular entrepreneurship training in order to upgrade their liquidity and cash management knowledge and practices to enhance their overall performance.

Keywords: liquidity management, owner-managed firm, profitability, survival

Procedia PDF Downloads 417
5584 Elephant Herding Optimization for Service Selection in QoS-Aware Web Service Composition

Authors: Samia Sadouki Chibani, Abdelkamel Tari

Abstract:

Web service composition combines available services to provide new functionality. Given the number of available services with similar functionalities and different non functional aspects (QoS), the problem of finding a QoS-optimal web service composition is considered as an optimization problem belonging to NP-hard class. Thus, an optimal solution cannot be found by exact algorithms within a reasonable time. In this paper, a meta-heuristic bio-inspired is presented to address the QoS aware web service composition; it is based on Elephant Herding Optimization (EHO) algorithm, which is inspired by the herding behavior of elephant group. EHO is characterized by a process of dividing and combining the population to sub populations (clan); this process allows the exchange of information between local searches to move toward a global optimum. However, with Applying others evolutionary algorithms the problem of early stagnancy in a local optimum cannot be avoided. Compared with PSO, the results of experimental evaluation show that our proposition significantly outperforms the existing algorithm with better performance of the fitness value and a fast convergence.

Keywords: bio-inspired algorithms, elephant herding optimization, QoS optimization, web service composition

Procedia PDF Downloads 318
5583 Resolving Problems Experienced by Involving Patients in the Development of Pharmaceutical Products at Post-Launch Stage of Pharmaceutical Product Development

Authors: Clara T. Fatoye, April Betts, Abayomi Odeyemi, Francis A. Fatoye, Isaac O. Odeyemi

Abstract:

Background: The post-launch stage is the last stage in the development of a pharmaceutical product. It is important to involve patients in the development of pharmaceutical products at the post-launch stage, as patients are the end-users of pharmaceutical products. It is expected that involving them might ensure an effective working relationship among the various stakeholders. However, involving patients in the development of pharmaceutical products comes with its problems. Hence, this study examined how to resolve problems experienced by involving patients in the developments of pharmaceutical products’ at post-launch consisting of Positioning of pharmaceutical products (POPP), detailing of pharmaceutical products (DOPP) and reimbursement and Formulary Submission (R&FS). Methods: A questionnaire was used for the present study. It was administered at the ISPOR Glasgow 2017 to 104 participants, all of which were professionals from Market access (MA) and health economics and outcomes research (HEOR) backgrounds. They were asked how the issues experienced by patients can be resolved. Participants responded under six domains as follows: communication, cost, effectiveness, external factors, Quality of life (QoL) and safety. Thematic analysis was carried out to identify strategies to resolve issues experienced by patients at the post-launch stage. Results: Three (3) factors cut across at POPP, DOPP, and R&FS that is (external factors, communication and QoL). The first resolution method was an external factor that is, the relationship with stakeholders and policymakers. Communication was also identified as a resolution method that can help to resolve problems experienced by patients at the post-launch stage. The third method was QoL as perceived by the patients based on professionals’ opinions. Other strategies that could be used to resolve problems experienced were the effectiveness of pharmaceutical products at the DOPP level and cost at R&FS. Conclusion: The study showed that focusing on external factors, communication, and patients’ QoL are methods for resolving issues experienced by involving patients at the post-launch stage of pharmaceutical product development. Hence, effective working relationships between patients, policymakers and stakeholders may help to resolve problems experienced at the post-launch stage. Healthcare policymakers are to be aware of these findings as they may help them to put appropriate strategies in place to enhance the involvement of patients in pharmaceutical product development at the post-launch stage, thereby improving the health outcomes of the patients.

Keywords: patients, pharmaceutical products, post-launch stage, quality of life, QoL

Procedia PDF Downloads 120
5582 The Effectiveness of Adaptive Difficulty Adjustment in Touch Tablet App on Young Children's Spatial Problem Solving Development

Authors: Chenchen Liu, Jacques Audran

Abstract:

Using tablet apps with a certain educational purpose to promote young children’s cognitive development, is quite common now. Developing an educational app on an Ipad like tablet, especially for a young child (age 3-5) requires an optimal level of challenge to continuously attract children’s attention and obtain an educational effect. Adaptive difficulty adjustment, which could dynamically set the difficulty in the challenge according to children’s performance, seems to be a good solution. Since space concept plays an important role in young children’s cognitive development, we made an experimental comparison in a French kindergarten between one group of 23 children using an educational app ‘Debout Ludo’ with adaptive difficulty settings and another group of 20 children using the previous version of ‘Debout Ludo’ with a classic incremental difficulty adjustment. The experiment results of spatial problem solving indicated that a significantly higher learning outcome was acquired by the young children who used the adaptive version of the app.

Keywords: adaptive difficulty, spatial problem solving, tactile tablet, young children

Procedia PDF Downloads 428
5581 An Elaboration Likelihood Model to Evaluate Consumer Behavior on Facebook Marketplace: Trust on Seller as a Moderator

Authors: Sharmistha Chowdhury, Shuva Chowdhury

Abstract:

Buying-selling new as well as second-hand goods like tools, furniture, household, electronics, clothing, baby stuff, vehicles, and hobbies through the Facebook marketplace has become a new paradigm for c2c sellers. This phenomenon encourages and empowers decentralised home-oriented sellers. This study adopts Elaboration Likelihood Model (ELM) to explain consumer behaviour on Facebook Marketplace (FM). ELM suggests that consumers process information through the central and peripheral routes, which eventually shape their attitudes towards posts. The central route focuses on information quality, and the peripheral route focuses on cues. Sellers’ FM posts usually include product features, prices, conditions, pictures, and pick-up location. This study uses information relevance and accuracy as central route factors. The post’s attractiveness represents cues and creates positive or negative associations with the product. A post with remarkable pictures increases the attractiveness of the post. So, post aesthetics is used as a peripheral route factor. People influenced via the central or peripheral route forms an attitude that includes multiple processes – response and purchase intention. People respond to FM posts through save, share and chat. Purchase intention reflects a positive image of the product and higher purchase intention. This study proposes trust on sellers as a moderator to test the strength of its influence on consumer attitudes and behaviour. Trust on sellers is assessed whether sellers have badges or not. A sample questionnaire will be developed and distributed among a group of random FM sellers who are selling vehicles on this platform to conduct the study. The chosen product of this study is the vehicle, a high-value purchase item. High-value purchase requires consumers to consider forming their attitude without any sign of impulsiveness seriously. Hence, vehicles are the perfect choice to test the strength of consumers attitudes and behaviour. The findings of the study add to the elaboration likelihood model and online second-hand marketplace literature.

Keywords: consumer behaviour, elaboration likelihood model, facebook marketplace, c2c marketing

Procedia PDF Downloads 129
5580 Participation Motivation and Financing Approach of Small and Medium Enterprises in Mergers and Acquisitions in Vietnam from the Viewpoint of Intermediaries

Authors: Nguyen Thi Hoang Hieu

Abstract:

Mergers and Acquisitions (M&A) activities have increasingly become popular in both developed and developing countries. It is also an attractive topic for researchers to exploit in various sectors such as business, economies or finance. However, activities of Small and Medium Enterprises (SMEs) in M&A activities for a long time have not been sufficiently studied to provide the complete picture of what has been really, particularly in the developing market like Vietnam. The study employs semi-structured in-depth interviews with experts who have worked for years in the M&A sector to explore the participation motivation of both buy side and sell side of M&A activities. In addition, through the interviews, the study attempts to explain how firms finance their M&A deals. The collected data then will be content-analyzed to reflect the study's expectations based on the theories and practices reviews. In addition, limitations and recommendations are given in the hope that the M&A performance in Vietnam can be improved in the future.

Keywords: mergers and acquisitions, Vietnam, small and medium enterprises, content-analysis, semi-structure in-depth interview

Procedia PDF Downloads 251
5579 The Impact of Social Customer Relationship Management on Brand Loyalty and Reducing Co-Destruction of Value by Customers

Authors: Sanaz Farhangi, Habib Alipour

Abstract:

The main objective of this paper is to explore how social media as a critical platform would increase the interactions between the tourism sector and stakeholders. Nowadays, human interactions through social media in many areas, especially in tourism, provide various experiences and information that users share and discuss. Organizations and firms can gain customer loyalty through social media platforms, albeit consumers' negative image of the product or services. Such a negative image can be reduced through constant communication between produces and consumers, especially with the availability of the new technology. Therefore, effective management of customer relationships in social media creates an extraordinary opportunity for organizations to enhance value and brand loyalty. In this study, we seek to develop a conceptual model for addressing factors such as social media, SCRM, and customer engagement affecting brand loyalty and diminish co-destruction. To support this model, we scanned the relevant literature using a comprehensive category of ideas in the context of marketing and customer relationship management. This will allow exploring whether there is any relationship between social media, customer engagement, social customer relationship management (SCRM), co-destruction, and brand loyalty. SCRM has been explored as a moderating factor in the relationship between customer engagement and social media to secure brand loyalty and diminish co-destruction of the company’s value. Although numerous studies have been conducted on the impact of social media on customers and marketing behavior, there are limited studies for investigating the relationship between SCRM, brand loyalty, and negative e-WOM, which results in the reduction of the co-destruction of value by customers. This study is an important contribution to the tourism and hospitality industry in orienting customer behavior in social media using SCRM. This study revealed that through social media platforms, management can generate discussion and engagement about the product and services, which facilitates customers feeling in an appositive way towards the firm and its product. Study has also revealed that customers’ complaints through social media have a multi-purpose effect; it can degrade the value of the product, but at the same time, it will motivate the firm to overcome its weaknesses and correct its shortcomings. This study has also implications for the managers and practitioners, especially in the tourism and hospitality sector. Future research direction and limitations of the research were also discussed.

Keywords: brand loyalty, co-destruction, customer engagement, SCRM, tourism and hospitality

Procedia PDF Downloads 104
5578 Ceratocystis manginecans Causal Agent of a Destructive Mangoes in Pakistan

Authors: Asma Rashid, Shazia Iram, Iftikhar Ahmad

Abstract:

Mango sudden death is an emerging problem in Pakistan. As its prevalence is observed in almost all mango growing areas and severity varied from 2-5% in Punjab and 5-10% in Sindh. Symptoms on affected trees include bark splitting, discoloration of the vascular tissue, wilting, gummosis and at the end rapid death. Total of n= 45 isolates were isolated from different mango growing areas of Punjab and Sindh. Pathogenicity of these fungal isolates was tested through artificial inoculation method on different hosts (potato tubers, detached mango leaves, detached mango twigs and mango plants) under controlled conditions and all were proved pathogenic with varying degree of aggressiveness in reference to control. The findings of the present study proved that out of these four methods, potato tubers inoculation method was the most ideal as this fix the inoculums on the target site. Increased fungal growth and spore numbers may be due to soft tissues of potato tubers from which Ceratocystis isolates can easily pass. Lesion area on potato tubers was in the range of 7.09-0.14 cm2 followed by detached mango twigs which were ranged from 0.48-0.09 cm2). All pathological results were proved highly significant at P<0.05 through ANOVA but isolate to isolate showed non-significant behaviour but they have the positive effect on lesion area. Re-isolation of respective fungi was achieved with 100 percent success which results in the verification of Koch’s postulates. DNA of fungal pathogens was successfully extracted through phenol chloroform method. Amplification was done through ITS, b-tubulin gene, and Transcription Elongation Factor (EF1-a) gene primers and the amplified amplicons were sequenced and compared from NCBI which showed 99-100 % similarity with Ceratocystis manginecans. Fungus Ceratocystis manginecans formed one of strongly supported sub-clades through phylogenetic tree. Results obtained through this work would be supportive in establishment of relation of isolates with their region and will give information about pathogenicity level of isolates that would be useful to develop the management policies to reduce the afflictions in orchards caused by mango sudden death.

Keywords: artificial inoculation, mango, Ceratocystis manginecans, phylogenetic, screening

Procedia PDF Downloads 236