Search results for: densimetric froude number
9430 Heat Transfer Correlations for Exhaust Gas Flow
Authors: Fatih Kantas
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Exhaust systems are key contributors to ground vehicles as a heat source. Understanding heat transfer in exhaust systems is related to defining effective parameter on heat transfer in exhaust system. In this journal, over 20 Nusselt numbers are investigated. This study shows advantages and disadvantages of various Nusselt numbers in different range Re, Pr and pulsating flow amplitude and frequency. Also (CAF) Convective Augmentation Factors are defined to correct standard Nusselt number for geometry and location of exhaust system. Finally, optimum Nusselt number and Convective Augmentation Factors are recommended according to Re, Pr and pulsating flow amplitude and frequency, geometry and location effect of exhaust system.Keywords: exhaust gas flow, heat transfer correlation, Nusselt, Prandtl, pulsating flow
Procedia PDF Downloads 3559429 Numerical Analysis of Multiplicity and Transition Phenomena in Natural Convection
Authors: Hadi Kafil, Ali Ecder
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Heat transfer by natural convection in two-dimensional and three-dimensional axisymmetric enclosure fitted with partially heated vertical walls is investigated numerically. The range of Rayleigh number is varied from 10³ until convective flow becomes unstable. This research focuses on multiplicity and transition phenomena in natural convection and is based on a parametric analysis to study the onset of bifurcations. It is found that, even at low Rayleigh numbers, the flow undergoes a series of turning-point bifurcations which increase the rate of natural convention. On the other hand, by partially heating or cooling the walls, more effective results can be achieved for both heating and cooling applications, such as cooling of electronic devices and heating processes in solidification and crystal growth.Keywords: natural convection, partial heated, onset of bifurcation, Rayleigh number
Procedia PDF Downloads 3719428 Effect of Organic Fertilization and Intercropping of Potato (Solanum Tuberosum) With Faba Bean (Vicia Faba) on Potato’s Yield
Authors: Laila Nassiri, Aziza Irhza, Jamal Ibijbijen, Fouad Rachidi, Ghizlane Echchgadda
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The introduction of agroecological practices in ecosystems can contribute to meeting the challenges posed by the diversion of current agricultural production systems towards efficient production methods that are more respectful of the environment, including a reasoned use of inputs and resources. Intercropping is one of these practices that requires the production of two or more crops on the same plot and during the same growing season. Organic fertilization also can contribute to increase the yield due to the potential availability of nutrients. The objective of this work is to study the effect of intercropping and organic fertilization, which are two important practices of agroecology, on potato yield. Intercropping of potato and faba bean was carried out at the Agroecology and Environment platform (ENA, Meknes). The soil is silty-clay, the climate is warm with an average temperature of 17.1°C, and the annual average rainfall of 511mm. Four treatments were tested: Potato sole crop (T1), potato + organic fertilization (T2), Potato + faba bean (T3), Potato + faba bean + organic fertilization (T4). The results showed that there is a significant effect of the treatment on the evolution of the agronomical characters studied, especially the number of leaves and the yield. The number of stems at t0 was equal to 1 in all treatments; it began to grow after 30 days from the date of sowing with a slight increase in treatments containing organic fertilization (T2-T4), then it stabilized 60 days after sowing. In terms of the mean value of the number of leaves, a significant difference was noted between the treatments, the highest value was recorded in treatment T2. The T2 treatment showed the highest average yield, followed by the control (T1). As for the yield, treatments T2 and T1 recorded the highest number of tubers. In order to evaluate two of the practices of agroecology, this work focuses on the evaluation of the effect of intercropping and organic fertilization on the growth and yield parameters of the potato. The results obtained show that agroecological practices have a significant effect on the measured parameters.Keywords: agroecology, intercropping, organic fertilization, potato yield
Procedia PDF Downloads 909427 Price Promotions and Inventory Decisions
Authors: George Hadjinicola, Andreas Soteriou
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This paper examines the relationship between the number of price promotions that a firm should conduct per year and the level of safety stocks that the firm should maintain. Price promotions result in temporary sales increases, which affect the operations function through (1) an increase in the quantities demanded and (2) an increase in safety stocks required to maintain the desired service level. We propose a modeling framework where both price promotions and improved service levels, operationalized through higher safety stocks, can affect sales. We treat the annual number of promotions as a decision variable. We identify market conditions where the operations function, through improved safety stocks, can complement price promotions or even play the leading role in sales increases.Keywords: price promotions, safety stocks, marketing/operations interface, mathematical model
Procedia PDF Downloads 979426 Comparative Growth Rates of Treculia africana Decne: Embryo in Varied Strengths of Murashige and Skoog Basal Medium
Authors: Okafor C. Uche, Agbo P. Ejiofor, Okezie C. Eziuche
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This study provides a regeneration protocol for Treculia africana Decne (an endangered plant) through embryo culture. Mature zygotic embryos of T. africana were excised from the seeds aseptically and cultured on varied strengths (full, half and quarter) of Murashige and Skoog (MS) basal medium supplemented. All treatments experienced 100±0.00 percent sprouting except for half and quarter strengths. Plantlets in MS full strength had the highest fresh weight, leaf area, and longest shoot length when compared to other treatments. All explants in full, half, quarter strengths and control had the same number of leaves and sprout rate. Between the treatments, there was a significant difference (P>0.05) in their effect on the length of shoot and root, number of adventitious root, leaf area, and fresh weight. Full strength had the highest mean value in all the above-mentioned parameters and differed significantly (P>0.05) from others except in shoot length, number of adventitious roots, and root length where it did not differ (P<0.05) from half strength. The result of this study indicates that full strength MS basal medium offers a better option for the optimum growth for Treculia africana regeneration in vitro.Keywords: medium strengths, Murashige and Skoog, Treculia africana, zygotic embryos
Procedia PDF Downloads 2559425 Effect of Geometry on the Aerodynamic Performance of Darrieus H Yype Vertical Axis Wind Turbine
Authors: Belkheir Noura, Rabah Kerfah, Boumehani Abdellah
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The influence of solidity variations on the aerodynamic performance of H type vertical axis wind turbine is studied in this paper. The wind turbine model used in this paper is the three-blade wind turbine with the symmetrical airfoil, NACA0021. The length of the chord is 0.265m. Numerical investigations were implemented for the different solidity by changing the radius and blade number. A two-dimensional model of the wind turbine is employed. The approach a Reynolds-Averaged Navier–Stokes equations, completed by the K- ώ SST turbulence model, is used. Motion mesh model capability of a computational fluid dynamics (CFD) solver is used. For each value of the solidity, the aerodynamics performances and the characteristics of the flow field are studied at several values of the tip speed ratio, λ = 0.5 to λ = 3, with an incoming wind speed of 8 m/s. The results show that increasing the number of blades will reduce the maximum value of the power coefficient of the wind turbine. Also, for the VAWT with a lower solidity can obtain the maximum Cp at a high tip speed ratio. The effects of changing the radius and blade number on aerodynamic performance are almost the same. Finally, for the validation, experimental data from the literature and computational results were compared. In conclusion, to study the influence of the solidity in the performances of the wind turbine is to provide the reference for the design of H type vertical axis wind turbines.Keywords: wind energy, darrieus h type vertical axis wind turbine, computational fluid dynamic, solidity
Procedia PDF Downloads 979424 Thinned Elliptical Cylindrical Antenna Array Synthesis Using Particle Swarm Optimization
Authors: Rajesh Bera, Durbadal Mandal, Rajib Kar, Sakti P. Ghoshal
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This paper describes optimal thinning of an Elliptical Cylindrical Array (ECA) of uniformly excited isotropic antennas which can generate directive beam with minimum relative Side Lobe Level (SLL). The Particle Swarm Optimization (PSO) method, which represents a new approach for optimization problems in electromagnetic, is used in the optimization process. The PSO is used to determine the optimal set of ‘ON-OFF’ elements that provides a radiation pattern with maximum SLL reduction. Optimization is done without prefixing the value of First Null Beam Width (FNBW). The variation of SLL with element spacing of thinned array is also reported. Simulation results show that the number of array elements can be reduced by more than 50% of the total number of elements in the array with a simultaneous reduction in SLL to less than -27dB.Keywords: thinned array, Particle Swarm Optimization, Elliptical Cylindrical Array, Side Lobe Label.
Procedia PDF Downloads 4459423 Effect of Number of Baffles on Pressure Drop and Heat Transfer in a Shell and Tube Heat Exchanger
Authors: A. Falavand Jozaei, A. Ghafouri, M. Mosavi Navaei
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In this paper for a given heat duty, study of number of baffles on pressure drop and heat transfer is considered in a STHX (Shell and Tube Heat Exchanger) with single segmental baffles. The effect of number of baffles from 9 to 52 baffles (baffle spacing variations from 4 to 24 inches) over OHTC (Overall Heat Hransfer Coefficient) to pressure drop ratio (U/Δp ratio). The results show that U/Δp ratio is low when baffle spacing is minimum (4 inches) because pressure drop is high; however, heat transfer coefficient is very significant. Then, with the increase of baffle spacing, pressure drop rapidly decreases and OHTC also decreases, but the decrease of OHTC is lower than pressure drop, so (U/Δp) ratio increases. After increasing baffles more than 12 inches, variation in pressure drop is gradual and approximately constant and OHTC decreases; Consequently, U/Δp ratio decreases again. If baffle spacing reaches to 24 inches, STHX will have minimum pressure drop, but OHTC decreases, so required heat transfer surface increases and U/Δp ratio decreases. After baffle spacing more than 12 inches, variation of shell side pressure drop is negligible. So optimum baffle spacing is suggested between 8 to 12 inches (43 to 63 percent of inside shell diameter) for a sufficient heat duty and low pressure drop.Keywords: shell and tube heat exchanger, single segmental baffle, overall heat transfer coefficient, pressure drop
Procedia PDF Downloads 5479422 Assessment of Barriers to the Clinical Adoption of Cell-Based Therapeutics
Authors: David Pettitt, Benjamin Davies, Georg Holländer, David Brindley
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Cellular based therapies, whose origins can be traced from the intertwined concepts of tissue engineering and regenerative medicine, have the potential to transform the current medical landscape and offer an approach to managing what were once considered untreatable diseases. However, despite a large increase in basic science activity in the cell therapy arena alongside a growing portfolio of cell therapy trials, the number of industry products available for widespread clinical use correlates poorly with such a magnitude of activity, with the number of cell-based therapeutics in mainstream use remaining comparatively low. This research serves to quantitatively assess the barriers to the clinical adoption of cell-based therapeutics through identification of unique barriers, specific challenges and opportunities facing the development and adoption of such therapies.Keywords: cell therapy, clinical adoption, commercialization, translation
Procedia PDF Downloads 4019421 Relationship between Interfacial Instabilities and Mechanical Strength of Multilayer Symmetric Polymer Melts
Authors: Mohammad Ranjbaran Madiseh
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In this research, an experimental apparatus has been developed for observing interfacial stability and deformation of multilayer pressure-driven channel flows. The interface instability of the co-extrusion flow of polyethylene and polypropylene is studied experimentally in a slit geometry. By investigating the growing interfacial wave (IW) and tensile stress of extrudate samples, a relationship between interfacial instability (II) and mechanical properties of polypropylene (PP) and high-density polyethylene (HDPE) has been established. It is shown that the mechanism of interfacial strength is related to interfacial instabilities as well as interfacial strength. It is shown that there is an ability to forecast the quality of final products in the co-extrusion process. In this study, it is found that the instability is controlled by its dominant wave number, which is associated with maximum tensile stress at the interface.Keywords: interfacial instability, interfacial strength, wave number, interfacial wave
Procedia PDF Downloads 929420 Fish Diversity of Two Lacustrine Wetlands of the Upper Benue Basin, Nigeria
Authors: D. L. David, J. A. Wahedi, Q. T. Zaku
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A study was conducted at River Mayo Ranewo and River Lau, Taraba State Nigeria. The two rivers empty into the Upper Benue Basin. A survey of visual encounter was conducted within the two wetlands from June to August, 2014. The fish record was based entirely on landings of fishermen, number of canoes that land fish was counted, types of nets and baits used on each sampling day. Fishes were sorted into taxonomic groups, identified to family/ species level, counted and weighed in groups by species. Other aquatic organisms captured by the fishermen were scallops, turtles and frogs. The relative species abundance was determined by dividing the number of species from a site by the total number of species from all tributaries/sites. The fish were preserved in 2% formaldehyde solution and taken to the laboratory, were identified through keys of identification to African fishes and field guides. Shannon-Wieiner index of species diversity indicated that the diversity was highest at River Mayo Ranewo than River Lau. Results showed that at River Mayo Ranewo, the family Mochokidae recorded the highest (23.15%), followed by Mormyridae (22.64%) and the least was the family Lepidosirenidae (0.04%). While at River Lau, the family Mochokidae recorded the highest occurrence of (24.1%), followed by Bagridae (20.20%), and then Mormyridae, which also was the second highest in River Lau, with 18.46% occurrence. There was no occurrence of Malapteruridae and Osteoglossidae (0%) in River Lau, but the least occurrence was the family Gymnarchidae (0.04%). According to the result from the t-test, the fish composition was not significantly different (p≤0.05).Keywords: Diversity Index, Lau, Mayo Ranewo, Wetlands
Procedia PDF Downloads 3629419 Investigating the Form of the Generalised Equations of Motion of the N-Bob Pendulum and Computing Their Solution Using MATLAB
Authors: Divij Gupta
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Pendular systems have a range of both mathematical and engineering applications, ranging from modelling the behaviour of a continuous mass-density rope to utilisation as Tuned Mass Dampers (TMD). Thus, it is of interest to study the differential equations governing the motion of such systems. Here we attempt to generalise these equations of motion for the plane compound pendulum with a finite number of N point masses. A Lagrangian approach is taken, and we attempt to find the generalised form for the Euler-Lagrange equations of motion for the i-th bob of the N -bob pendulum. The co-ordinates are parameterized as angular quantities to reduce the number of degrees of freedom from 2N to N to simplify the form of the equations. We analyse the form of these equations up to N = 4 to determine the general form of the equation. We also develop a MATLAB program to compute a solution to the system for a given input value of N and a given set of initial conditions.Keywords: classical mechanics, differential equation, lagrangian analysis, pendulum
Procedia PDF Downloads 2119418 Visualization of the Mobility Patterns of Public Bike Sharing System in Seoul
Authors: Young-Hyun Seo, Hosuk Shin, Eun-Hak Lee, Seung-Young Kho
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This study analyzed and visualized the rental and return data of the public bike sharing system in Seoul, Ttareungyi, from September 2015 to October 2017. With the surge of system users, the number of times of collection and distribution in 2017 increased by three times compared to 2016. The city plans to deploy about 20,000 public bicycles by the end of 2017 to expand the system. Based on about 3.3 million historical data, we calculated the average trip time and the number of trips from one station to another station. The mobility patterns between stations are graphically displayed using R and Tableau. Demand for public bike sharing system is heavily influenced by day and weather. As a result of plotting the number of rentals and returns of some stations on weekdays and weekends at intervals of one hour, there was a difference in rental patterns. As a result of analysis of the rental and return patterns by time of day, there were a lot of returns at the morning peak and more rentals at the afternoon peak at the center of the city. It means that stock of bikes varies largely in the time zone and public bikes should be rebalanced timely. The result of this study can be applied as a primary data to construct the demand forecasting function of the station when establishing the rebalancing strategy of the public bicycle.Keywords: demand forecasting, mobility patterns, public bike sharing system, visualization
Procedia PDF Downloads 1919417 Multiscale Structures and Their Evolution in a Screen Cylinder Wake
Authors: Azlin Mohd Azmi, Tongming Zhou, Akira Rinoshika, Liang Cheng
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The turbulent structures in the wake (x/d =10 to 60) of a screen cylinder have been reduced to understand the roles of the various structures as evolving downstream by comparing with those obtained in a solid circular cylinder wake at Reynolds number, Re of 7000. Using a wavelet multi-resolution technique, the flow structures are decomposed into a number of wavelet components based on their central frequencies. It is observed that in the solid cylinder wake, large-scale structures (of frequency f0 and 1.2 f0) make the largest contribution to the Reynolds stresses although they start to lose their roles significantly at x/d > 20. In the screen cylinder wake, the intermediate-scale structures (2f0 and 4f0) contribute the most to the Reynolds stresses at x/d =10 before being taken over by the large-scale structures (f0) further downstream.Keywords: turbulent structure, screen cylinder, vortex, wavelet multi-resolution analysis
Procedia PDF Downloads 4609416 Teacher Education and the Impact of Higher Education Foreign Language Requirements on Students with Learning Disabilities
Authors: Joao Carlos Koch Junior, Risa Takashima
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Learning disabilities have been extensively and increasingly studied in recent times. In spite of this, there is arguably a scarce number of studies addressing a key issue, which is the impact of foreign-language requirements on students with learning disabilities in higher education, and the lack of training or awareness of teachers regarding language learning disabilities. This study is an attempt to address this issue. An extensive review of the literature in multiple fields will be summarised. This, paired with a case-analysis of a university adopting a more inclusive approach towards special-needs students in its foreign-language programme, this presentation aims to establish a link between different studies and propose a number of suggestions to make language classrooms more inclusive.Keywords: foreign language teaching, higher education, language teacher education, learning disabilities
Procedia PDF Downloads 4519415 Operations Research Applications in Audit Planning and Scheduling
Authors: Abdel-Aziz M. Mohamed
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This paper presents a state-of-the-art survey of the operations research models developed for internal audit planning. Two alternative approaches have been followed in the literature for audit planning: (1) identifying the optimal audit frequency; and (2) determining the optimal audit resource allocation. The first approach identifies the elapsed time between two successive audits, which can be presented as the optimal number of audits in a given planning horizon, or the optimal number of transactions after which an audit should be performed. It also includes the optimal audit schedule. The second approach determines the optimal allocation of audit frequency among all auditable units in the firm. In our review, we discuss both the deterministic and probabilistic models developed for audit planning. In addition, game theory models are reviewed to find the optimal auditing strategy based on the interactions between the auditors and the clients.Keywords: operations research applications, audit frequency, audit-staff scheduling, audit planning
Procedia PDF Downloads 8169414 Social Contact Patterns among School-Age Children in Taiwan
Authors: Dih Ling Luh, Zhi Shih You, Szu Chieh Chen
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Social contact patterns among school-age children play an important role in the epidemiology of infectious disease. Since many of the greatest threats to human health are spread by direct person-to-person contact, understanding the spread of respiratory pathogens and patterns of human interactions are public health priorities. This study used social contact diaries to compare the number of contacts per day per participant across different flu/non-flu seasons and weekend/weekday. We also present contact properties such as sex, age, masking, setting, frequency, duration, and contact types among school-age children (grades 7–8). The sample size with pair-wise comparisons for the seasons (flu/non-flu) and stratification by location were 54 and 83, respectively. There was no difference in the number of contacts during the flu and non-flu seasons, with averages of 16.3 (S.D. = 12.9) and 14.6 (S.D. = 9.5) people, respectively. Weekdays were associated with 23% and 28% more contacts than weekend days during the non-flu and flu seasons, respectively (p < 0.001) (Wilcoxon signed-rank test).Keywords: contact patterns, behavior, influenza, social mixing
Procedia PDF Downloads 3469413 Numerical Investigation of Fluid Flow, Characteristics of Thermal Performance and Enhancement of Heat Transfer of Corrugated Pipes with Various Geometrical Configurations
Authors: Ahmed Ramadhan Al-Obaidi, Jassim Alhamid
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In this investigation, the flow pattern, characteristics of thermal-hydraulic, and improvement of heat transfer performance are evaluated using a numerical technique in three dimensions corrugated pipe heat exchanger. The modification was made under different corrugated pipe geometrical parameters, including corrugated ring angle (CRA), distance between corrugated ring (DBCR), and corrugated diameter (CD), the range of Re number from 2000 to 12000. The numerical results are validated with available experimental data. The numerical outcomes reveal that there is an important change in flow field behaviour and a significant increase in friction factor and improvement in heat transfer performance owing to the use of the corrugated shape in the heat exchanger pipe as compared to the conventional smooth pipe. Using corrugated pipe with different configurations makes the flow more turbulence, flow separation, boundary layer distribution, flow mixing, and that leads to augmenting the performance of heat transfer. Moreover, the value of pressure drop, and the Nusselt number increases as the corrugated pipe geometrical parameters increase. Furthermore, the corrugation configuration shapes have an important influence on the thermal evaluation performance factor, and the maximum value was more than 1.3. Numerical simulation can be performed to predict the various geometrical configurations effects on fluid flow, thermal performance, and heat transfer enhancement.Keywords: corrugated ring angle, corrugated diameter, Nusselt number, heat transfer
Procedia PDF Downloads 1449412 Radar Track-based Classification of Birds and UAVs
Authors: Altilio Rosa, Chirico Francesco, Foglia Goffredo
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In recent years, the number of Unmanned Aerial Vehicles (UAVs) has significantly increased. The rapid development of commercial and recreational drones makes them an important part of our society. Despite the growing list of their applications, these vehicles pose a huge threat to civil and military installations: detection, classification and neutralization of such flying objects become an urgent need. Radar is an effective remote sensing tool for detecting and tracking flying objects, but scenarios characterized by the presence of a high number of tracks related to flying birds make especially challenging the drone detection task: operator PPI is cluttered with a huge number of potential threats and his reaction time can be severely affected. Flying birds compared to UAVs show similar velocity, RADAR cross-section and, in general, similar characteristics. Building from the absence of a single feature that is able to distinguish UAVs and birds, this paper uses a multiple features approach where an original feature selection technique is developed to feed binary classifiers trained to distinguish birds and UAVs. RADAR tracks acquired on the field and related to different UAVs and birds performing various trajectories were used to extract specifically designed target movement-related features based on velocity, trajectory and signal strength. An optimization strategy based on a genetic algorithm is also introduced to select the optimal subset of features and to estimate the performance of several classification algorithms (Neural network, SVM, Logistic regression…) both in terms of the number of selected features and misclassification error. Results show that the proposed methods are able to reduce the dimension of the data space and to remove almost all non-drone false targets with a suitable classification accuracy (higher than 95%).Keywords: birds, classification, machine learning, UAVs
Procedia PDF Downloads 2249411 Performance Analysis and Optimization for Diagonal Sparse Matrix-Vector Multiplication on Machine Learning Unit
Authors: Qiuyu Dai, Haochong Zhang, Xiangrong Liu
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Diagonal sparse matrix-vector multiplication is a well-studied topic in the fields of scientific computing and big data processing. However, when diagonal sparse matrices are stored in DIA format, there can be a significant number of padded zero elements and scattered points, which can lead to a degradation in the performance of the current DIA kernel. This can also lead to excessive consumption of computational and memory resources. In order to address these issues, the authors propose the DIA-Adaptive scheme and its kernel, which leverages the parallel instruction sets on MLU. The researchers analyze the effect of allocating a varying number of threads, clusters, and hardware architectures on the performance of SpMV using different formats. The experimental results indicate that the proposed DIA-Adaptive scheme performs well and offers excellent parallelism.Keywords: adaptive method, DIA, diagonal sparse matrices, MLU, sparse matrix-vector multiplication
Procedia PDF Downloads 1369410 The Impact of Female Characters on a Movie’s Return on Investment
Authors: Raghav Lakhotia, Sameer Ganu, Anshul Goel, Abhishek Kumar
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In the age and times where women’s empowerment is a significant topic of discussion, we aim to analyze the potential gender diversity influence on box office revenues. The following research is carried out by collecting data from 400 Hollywood movies between the years 2014-2017 and performing regression analysis to find a correlation between the presence of female characters in movies and their return on investment (ROI). The paper finds that there is a positive relationship between the performance of the movies (its ROI) and the gender diversity i.e. the more the number of female characters, the higher the revenue generated. Another factor such as Number of Votes also has a direct impact on the revenue of the movie. The research not only takes into consideration the mere presence of women on screen but also the exchange of at least one dialogue among themselves, which is presented by the Bechdel Score of the movie.Keywords: Bechdel, diversity, Hollywood, return on investment
Procedia PDF Downloads 2009409 Sediment Trapping by Seagrass Blades under Oscillatory Flow
Authors: Aina Barcelona, Carolyn Oldham, Jordi Colomer, Jordi Garcia-Orellana, Teresa Serra
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Seagrass meadows increase the sedimentation within the canopy. However, there is still a lack of knowledge about how seagrasses impact the vertical distribution of sediment coming from external sources and reaches the meadow. This study aims to determine the number of particles retained by a seagrass meadow. Based on the hydrodynamics in the vertical direction, a meadow can be separated into different compartments: the blades, the seabed, within the canopy layer, and the above canopy layer. A set of laboratory experiments were conducted under different hydrodynamic conditions and canopy densities with the purpose to mimic the real field conditions. This study demonstrates and quantifies that seagrass meadows decrease the volume of the suspended sediment by two mechanisms: capturing the suspended sediment by the seagrass blades and promoting the particle sedimentation to the seabed. This study also demonstrates that the number of sediment particles trapped by single seagrass blades decreases with canopy density. However, when considering the trapping by the total number of blades, the sediment captured by all the blades of the meadow increases with canopy density. Furthermore, comparing with the bare seabed, this study demonstrated that there is a reduction in the suspended particles within the canopy, which implies an improvement in the water clarity. In addition, the particle sedimentation on the seabed increases with the canopy density compared with the bare seabed, making evident the contribution of the vegetation in enhancing sedimentation.Keywords: seagrass, sediment capture, turbulent kinetic energy, oscillatory flow
Procedia PDF Downloads 2359408 Steady and Oscillatory States of Swirling Flows under an Axial Magnetic Field
Authors: Brahim Mahfoud, Rachid Bessaïh
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In this paper, a numerical study of steady and oscillatory flows with heat transfer submitted to an axial magnetic field is studied. The governing Navier-Stokes, energy, and potential equations along with appropriate boundary conditions are solved by using the finite-volume method. The flow and temperature fields are presented by stream function and isotherms, respectively. The flow between counter-rotating end disks is very unstable and reveals a great richness of structures. The results are presented for various values of the Hartmann number, Ha=5, 10, 20, and 30, and Richardson numbers , Ri=0, 0.5, 1, 2, and 4, in order to see their effects on the value of the critical Reynolds number, Recr. Stability diagrams are established according to the numerical results of this investigation. These diagrams put in evidence the dependence of Recr with the increase of Ha for various values of Ri.Keywords: swirling, counter-rotating end disks, magnetic field, oscillatory, cylinder
Procedia PDF Downloads 3259407 When Mobile Work Creates More Discrimination
Authors: Marie-Therese Claes, Anett Hermann
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With the advent of the web and information technology since the end of the 20ᵗʰ century, digitalization has revolutionized our everyday life, from shopping and dating to education and transportation. The world of work is one of the areas that has been highly transformed by changing the time and spatial limits of the work. The expansion of the internet, wireless, and easily portable devices such as laptop computers and mobile phones has enabled us to work almost from any place at any time. As a result, telework, which started in the 1950s and elevated in the 1970s, steeply raised to a new level in 21ˢᵗ century. Telework consists of various forms of work done from outside the traditional workplace by using information technologies. The social distancing and lockdown measures that have been taken to reduce the spread of the virus in many countries worldwide resulted in an increasing number of teleworkers and made “working from home’’ synonymous with telework. Post-COVID-19, the number of teleworkers is still higher than before the pandemic period, and the interest in expanding teleworking has been growing too. Notwithstanding the advantages ushered by telework, it also has a number of drawbacks that negatively affect organizations and employees. The intention of this piece of work is not to indicate a causational relationship between telework and discrimination. Our aim is to indicate some unintended and/or unnoticed deleterious effects of telework in reinforcing discrimination and to instigate discussion on how to mitigate the effects. To do so, this insight indicates how telework reinforces traditional gender roles and how organizational culture towards telework and its access to employees at different levels of the organizational hierarchy opens the room for discrimination.Keywords: mobile work, discrimination, gender roles, organizational culture
Procedia PDF Downloads 679406 Study of Mini Steel Re-Rolling and Pickling Mills for the Reduction of Accidents and Health Hazards
Authors: S. P. Rana
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Objectives: For the manufacture of a very thin strip or a strip with a high-quality finish, the stainless steel sheet that is called billet is re-rolled in re-rolling mill to make stainless steel sheet of 18 gauges. The rolls of re-rolling mill exert tremendous pressure over the sheet and there is likely chance of breaking of stainless steel strip from the sheet. The objective of the study was to minimise the number of accidents in steel re-rolling mills due to ejection of stainless steel strip and to minimize the pollution caused by the pickling process used in these units. Methods: Looking into the high rate of frequency and severity of accidents as well as pollution hazard in re-rolling and pickling mills, it becomes essential to make necessary arrangements for prevention of accidents in such type of industry. The author carried out survey/inspections of a large number of re-rolling and pickling mills and allied units. During the course of inspection, the working of these steel re-rolling and pickling mills was closely studied and monitored. A number of accidents involving re-rolling mills were investigated and subsequently remedial measures to prevent the occurrence of such accidents were suggested. Assessment of occupational safety and health system of these units was carried out and compliance level of the statutory requirements was checked. The workers were medically examined and monitored to ascertain their health conditions. Results: Proper use of safety gadgets by workers, machine guarding and regular training brought down the risk to an acceptable level and discharged effluent pollution was brought down to permissible limits. The fatal accidents have been reduced by 83%. Conclusions: Effective enforcement and implementation of the directions/suggestions given to the managements of such units brought down the no. of accidents to a rational level. The number of fatal accidents has reduced by 83% during the study period. The effective implementation of pollution control device curtailed the pollution level to an acceptable level.Keywords: re-rolling mill, hazard, accident, health hazards
Procedia PDF Downloads 4439405 Female’s Involvement in Real Estate Business in Nigeria: A Case Study of Lagos State
Authors: Osaretin Rosemary Uyi, A. O. Ogungbemi
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Female involvement in policy making and partnership in a man-driven-world is fast gaining international recognition. The Nigeria commercial real estate is one of the sectors of the economy that has a significant number of the male in the business. This study was conducted to assess the participation of females in estate management in Lagos state, Nigeria. Lagos is the commercial nerve center of Nigeria having the highest number of real estate practitioners and investors. The population due to the daily influx of people has made real estate business to continue to grow in this part of Nigeria. A structured questionnaire duly pre-tested and validated was used to elicit information from the respondents. The data collected were presented using tables and charts and were analyzed using descriptive statistical tools such as frequency counts, percentages, were used to test the hypothesis. The results also indicated that most females that participated in commercial real estate business are educated (80%), fell within 31-40 years of age (75%) and of high income status (88%) earn above ₦800,000 per year, while 10% are real estate investors and 82% of the female in the sector are employee. The study concluded that the number of female participating in various aspect of commercial real estate business in the study area was moderate while the numbers of female investors are low when compared to male. This might be due to the problems associated with rent collection, land disputes and other issues that are associated with property management in Nigeria. It is therefore recommended that females in real estate should be empowered and encouraged to match with their male counterpart.Keywords: commercial real estate, empowerment, female, participation, property management
Procedia PDF Downloads 3339404 The Analogue of a Property of Pisot Numbers in Fields of Formal Power Series
Authors: Wiem Gadri
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This study delves into the intriguing properties of Pisot and Salem numbers within the framework of formal Laurent series over finite fields, a domain where these numbers’ spectral charac-teristics, Λm(β) and lm(β), have yet to be fully explored. Utilizing a methodological approach that combines algebraic number theory with the analysis of power series, we extend the foundational work of Erdos, Joo, and Komornik to this new setting. Our research uncovers bounds for lm(β), revealing how these depend on the degree of the minimal polynomial of β and thus offering a novel characterization of Pisot and Salem formal power series. The findings significantly contribute to our understanding of these numbers, highlighting their distribution and properties in the context of formal power series. This investigation not only bridges number theory with formal power series analysis but also sets the stage for further interdisciplinary research in these areas.Keywords: Pisot numbers, Salem numbers, formal power series, over a finite field
Procedia PDF Downloads 519403 Quality and Quantity in the Strategic Network of Higher Education Institutions
Authors: Juha Kettunen
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This study analyzes the quality and the size of the strategic network of higher education institutions. The study analyses the concept of fitness for purpose in quality assurance. It also analyses the transaction costs of networking that have consequences on the number of members in the network. Empirical evidence is presented of the Consortium on Applied Research and Professional Education, which is a European strategic network of six higher education institutions. The results of the study support the argument that the number of members in the strategic network should be relatively small to provide high quality results. The practical importance is that networking has been able to promote international research and development projects. The results of this study are important for those who want to design and improve international networks in higher education.
Keywords: balanced scorecard, higher education, social networking, strategic planning
Procedia PDF Downloads 3509402 Bullying Rates Among Students with Special Needs in the United States
Authors: Kaycee Bills
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Past studies have indicated students who have disabilities are at a higher risk of experiencing bullying victimization in comparison to other student groups. Extracurricular activity participation has been shown to establish better social outcomes for students. These positive social outcomes indirectly decrease the number of times a student is bullied. The following study uses the National Crime Victimization Survey – School Crime Supplement (NCVS/SCS) to analyze the bullying concurrences experienced among students, with disabilities being a focal variable. To explore the relationship between extracurricular involvement and bullying occurrence rates, this study employs a binary logistic regression to determine if athletic and non-athletic extracurricular activities have an impact on the number of times a student with disabilities experiences bullying. Implications for future social welfare practice and research are discussed.Keywords: disability, bullying, extracurricular activities, athletics
Procedia PDF Downloads 1619401 Traditional Uses of Medicinal Plants in Albania: Historical and Theoretical Considerations
Authors: Ani Bajrami
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The birth of traditional medicine is related to plant diversity in a region, and the knowledge regarding them has been used and culturally transmitted over generations by members of a certain society. In this context, Traditional Ecological Knowledge (TEK) concerning the use of plants for medicinal purposes had survival value and was adaptive for people living in different habitats around the world. Albanian flora has a high considerably number of medicinal plants, and they have been extensively used albeit expressed in folk medicinal knowledge and practices. Over the past decades, a number of ethnobotanical studies and extensive fieldwork has been conducted in Albania both by local and foreign scientists. In addition, ethnobotany is experiencing a theoretical and conceptual diversification. This article is a historical review of ethnobotanical studies conducted in Albania after the Second World War and provides theoretical considerations on how these studies should be conducted in the future.Keywords: medicinal plants, traditional ecological knowledge, historical ethnobotany, theory, albania
Procedia PDF Downloads 175