Search results for: dynamic creep
2319 Getting Back Out There Looking like That: A Visual Critique of Rebecca Welton’s Costuming in Reference to Female Representation in Television
Authors: Abigail R. Gardner
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With the rise of big budget television comes a demand for more nuanced characters. However, female characters are often underdeveloped, especially those who do not fit neatly into societal norms. This study examines how Ted Lasso’s Rebecca Welton challenges this idea by using her on-screen fashion to mirror her motivations and character development. Through detailed analysis, this research explores how Rebecca’s wardrobe adds depth to her character, contrasting traditional strategies of costuming female characters in mainstream movies and television. While women, especially older women, are getting more screen time, very few have been given a wardrobe to reflect their dynamic characters. Rebecca’s costumes represent a form of visual storytelling typically reserved for film, but with the rise of single-camera television, there is an opportunity to redefine the relationship between women and fashion on screen.Keywords: costume design, gender and media, visual storytelling, women in television
Procedia PDF Downloads 162318 H∞ Takagi-Sugeno Fuzzy State-Derivative Feedback Control Design for Nonlinear Dynamic Systems
Authors: N. Kaewpraek, W. Assawinchaichote
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This paper considers an H∞ TS fuzzy state-derivative feedback controller for a class of nonlinear dynamical systems. A Takagi-Sugeno (TS) fuzzy model is used to approximate a class of nonlinear dynamical systems. Then, based on a linear matrix inequality (LMI) approach, we design an H∞ TS fuzzy state-derivative feedback control law which guarantees L2-gain of the mapping from the exogenous input noise to the regulated output to be less or equal to a prescribed value. We derive a sufficient condition such that the system with the fuzzy controller is asymptotically stable and H∞ performance is satisfied. Finally, we provide and simulate a numerical example is provided to illustrate the stability and the effectiveness of the proposed controller.Keywords: h-infinity fuzzy control, an LMI approach, Takagi-Sugano (TS) fuzzy system, the photovoltaic systems
Procedia PDF Downloads 3832317 Multi-Level Priority Based Task Scheduling Algorithm for Workflows in Cloud Environment
Authors: Anju Bala, Inderveer Chana
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Task scheduling is the key concern for the execution of performance-driven workflow applications. As efficient scheduling can have major impact on the performance of the system, task scheduling is often chosen for assigning the request to resources in an efficient way based on cloud resource characteristics. In this paper, priority based task scheduling algorithm has been proposed that prioritizes the tasks based on the length of the instructions. The proposed scheduling approach prioritize the tasks of Cloud applications according to the limits set by six sigma control charts based on dynamic threshold values. Further, the proposed algorithm has been validated through the CloudSim toolkit. The experimental results demonstrate that the proposed algorithm is effective for handling multiple task lists from workflows and in considerably reducing Makespan and Execution time.Keywords: cloud computing, priority based scheduling, task scheduling, VM allocation
Procedia PDF Downloads 5162316 Evolution of Classroom Languaging over the Years: Prospects for Teaching Mathematics Differently
Authors: Jabulani Sibanda, Clemence Chikiwa
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This paper traces diverse language practices representative of equally diverse conceptions of language. To be dynamic with languaging practices, one needs to appreciate nuanced languaging practices, their challenges, prospects, and opportunities. The paper presents what we envision as three major conceptions of language that give impetus to diverse language practices. It examines theoretical models of the bilingual mental lexicon and how they inform language practices. The paper explores classroom languaging practices that have been promulgated and experimented with. The paper advocates the deployment of multisensory semiotic systems to complement linguistic classroom communication and the acknowledgement of learners’ linguistic and semiotic resources as valid in the learning enterprise. It recommends the enactment of specific clauses on language in education policies and curriculum documents that empower classroom interactants to exercise discretion in languaging practices.Keywords: languaging, monolingual, multilingual, semiotic and linguistic repertoire
Procedia PDF Downloads 712315 Behaviour of Reinforced Concrete Infilled Frames under Seismic Loads
Authors: W. Badla
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A significant portion of the buildings constructed in Algeria is structural frames with infill panels which are usually considered as non structural components and are neglected in the analysis. However, these masonry panels tend to influence the structural response. Thus, these structures can be regarded as seismic risk buildings, although in the Algerian seismic code there is little guidance on the seismic evaluation of infilled frame buildings. In this study, three RC frames with 2, 4, and 8 story and subjected to three recorded Algerian accelerograms are studied. The diagonal strut approach is adopted for modeling the infill panels and a fiber model is used to model RC members. This paper reports on the seismic evaluation of RC frames with brick infill panels. The results obtained show that the masonry panels enhance the load lateral capacity of the buildings and the infill panel configuration influences the response of the structures.Keywords: seismic design, RC frames, infill panels, non linear dynamic analysis
Procedia PDF Downloads 5452314 Seismic Analysis of Structurally Hybrid Wind Mill Tower
Authors: Atul K. Desai, Hemal J. Shah
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The tall windmill towers are designed as monopole tower or lattice tower. In the present research, a 125-meter high hybrid tower which is a combination of lattice and monopole type is proposed. The response of hybrid tower is compared with conventional monopole tower. The towers were analyzed in finite element method software considering nonlinear seismic time history load. The synthetic seismic time history for different soil is derived using the SeismoARTIF software. From the present research, it is concluded that, in the hybrid tower, we are not getting resonance condition. The base shear is less in hybrid tower compared to monopole tower for different soil conditions.Keywords: dynamic analysis, hybrid wind mill tower, resonance condition, synthetic time history
Procedia PDF Downloads 1472313 New Desiccant Solar Unit for Air Conditioning and Desalination: Study of the Compartments of Desalination and Water Condensation
Authors: Zied Guidara, Alexander Morgenstern, Aref Maalej
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In this paper, a new desiccant solar unit for air conditioning and desalination is presented first. Secondly, a dynamic modelling study of the desiccant wheel is developed. After that, a simulation study and an experimental investigation of the behaviour of the desiccant wheel are developed. The experimental investigation is done in the chamber of commerce in Freiburg-Germany. Indeed, the variations of calculated and measured temperatures and specific humidity of dehumidified and rejected air are presented where a good agreement is found when comparing the model predictions with experimental data under the considered range of operating conditions. Finally, the study of the compartments of desalination and water condensation shows that the unit can produce an acceptable quantity of water at the same time of the air conditioning operation.Keywords: air conditioning, desalination, condensation, design, desiccant wheel, modelling, experimental investigation
Procedia PDF Downloads 3832312 Sliding Mode Control of Autonomous Underwater Vehicles
Authors: Ahmad Forouzantabar, Mohammad Azadi, Alireza Alesaadi
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This paper describes a sliding mode controller for autonomous underwater vehicles (AUVs). The dynamic of AUV model is highly nonlinear because of many factors, such as hydrodynamic drag, damping, and lift forces, Coriolis and centripetal forces, gravity and buoyancy forces, as well as forces from thruster. To address these difficulties, a nonlinear sliding mode controller is designed to approximate the nonlinear dynamics of AUV and improve trajectory tracking. Moreover, the proposed controller can profoundly attenuate the effects of uncertainties and external disturbances in the closed-loop system. Using the Lyapunov theory the boundedness of AUV tracking errors and the stability of the proposed control system are also guaranteed. Numerical simulation studies of an AUV are included to illustrate the effectiveness of the presented approach.Keywords: lyapunov stability, autonomous underwater vehicle, sliding mode controller, electronics engineering
Procedia PDF Downloads 6092311 Dark Tourism and Local Development. Creating a Dark Urban Route
Authors: Christos N. Tsironis, Loanna Mitaftsi
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Currently, the various forms of tours and touristic visits to destinations associated with the “dark” facets of the past constitute one of the most dynamic fields of touristic initiatives and economic development. This analysis focuses on the potential development of urban dark routes. It aims a) to shed light to touristic, social, and ethical considerations and to describe some of the trends and links combining heritage and dark tourism in post-pandemic societies and b) to explore the possibilities of developing a new and polymorphic form of dark tourism in Thessaloniki, Greece, a distinctive heritage destination. The analysis concludes with a detailed dark route designed to serve a new, polymorphic and sustainable touristic product that describes a dark past with places, sights, and monuments and narrates stories and events stigmatized by death, disaster, and violence throughout the city’s history.Keywords: dark tourism, dark urban route, local development, polymorphic tourism
Procedia PDF Downloads 2112310 Atomic Force Microscopy Studies of DNA Binding Properties of the Archaeal Mini Chromosome Maintenance Complex
Authors: Amna Abdalla Mohammed Khalid, Pietro Parisse, Silvia Onesti, Loredana Casalis
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Basic cellular processes as DNA replication are crucial to cell life. Understanding at the molecular level the mechanisms that govern DNA replication in proliferating cells is fundamental to understand disease connected to genomic instabilities, as a genetic disease and cancer. A key step for DNA replication to take place, is unwinding the DNA double helix and this carried out by proteins called helicases. The archaeal MCM (minichromosome maintenance) complex from Methanothermobacter thermautotrophicus have being studied using Atomic Force Microscopy (AFM), imaging in air and liquid (Physiological environment). The accurate analysis of AFM topographic images allowed to understand the static conformations as well the interaction dynamic of MCM and DNA double helix in the present of ATP.Keywords: DNA, protein-DNA interaction, MCM (mini chromosome manteinance) complex, atomic force microscopy (AFM)
Procedia PDF Downloads 3052309 Investigation of Different Control Stratgies for UPFC Decoupled Model and the Impact of Location on Control Parameters
Authors: S. A. Al-Qallaf, S. A. Al-Mawsawi, A. Haider
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In order to evaluate the performance of a unified power flow controller (UPFC), mathematical models for steady state and dynamic analysis are to be developed. The steady state model is mainly concerned with the incorporation of the UPFC in load flow studies. Several load flow models for UPFC have been introduced in literature, and one of the most reliable models is the decoupled UPFC model. In spite of UPFC decoupled load flow model simplicity, it is more robust compared to other UPFC load flow models and it contains unique capabilities. Some shortcoming such as additional set of nonlinear equations are to be solved separately after the load flow solution is obtained. The aim of this study is to investigate the different control strategies that can be realized in the decoupled load flow model (individual control and combined control), and the impact of the location of the UPFC in the network on its control parameters.Keywords: UPFC, decoupled model, load flow, control parameters
Procedia PDF Downloads 5512308 Global Analysis in a Growth Economic Model with Perfect-Substitution Technologies
Authors: Paolo Russu
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The purpose of the present paper is to highlight some features of an economic growth model with environmental negative externalities, giving rise to a three-dimensional dynamic system. In particular, we show that the economy, which is based on a Perfect-Substitution Technologies function of production, has no neither indeterminacy nor poverty trap. This implies that equilibrium select by economy depends on the history (initial values of state variable) of the economy rather than on expectations of economies agents. Moreover, by contrast, we prove that the basin of attraction of locally equilibrium points may be very large, as they can extend up to the boundary of the system phase space. The infinite-horizon optimal control problem has the purpose of maximizing the representative agent’s instantaneous utility function depending on leisure and consumption.Keywords: Hopf bifurcation, open-access natural resources, optimal control, perfect-substitution technologies, Poincarè compactification
Procedia PDF Downloads 1692307 An Implementation of Meshless Method for Modeling an Elastoplasticity Coupled to Damage
Authors: Sendi Zohra, Belhadjsalah Hedi, Labergere Carl, Saanouni Khemais
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The modeling of mechanical problems including both material and geometric nonlinearities with Finite Element Method (FEM) remains challenging. Meshless methods offer special properties to get rid of well-known drawbacks of the FEM. The main objective of Meshless Methods is to eliminate the difficulty of meshing and remeshing the entire structure by simply insertion or deletion of nodes, and alleviate other problems associated with the FEM, such as element distortion, locking and others. In this study, a robust numerical implementation of an Element Free Galerkin Method for an elastoplastic coupled to damage problem is presented. Several results issued from the numerical simulations by a DynamicExplicit resolution scheme are analyzed and critically compared with Element Finite Method results. Finally, different numerical examples are carried out to demonstrate the efficiency of this method.Keywords: damage, dynamic explicit, elastoplasticity, isotropic hardening, meshless
Procedia PDF Downloads 2922306 Prediction of Oxygen Transfer and Gas Hold-Up in Pneumatic Bioreactors Containing Viscous Newtonian Fluids
Authors: Caroline E. Mendes, Alberto C. Badino
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Pneumatic reactors have been widely employed in various sectors of the chemical industry, especially where are required high heat and mass transfer rates. This study aimed to obtain correlations that allow the prediction of gas hold-up (Ԑ) and volumetric oxygen transfer coefficient (kLa), and compare these values, for three models of pneumatic reactors on two scales utilizing Newtonian fluids. Values of kLa were obtained using the dynamic pressure-step method, while was used for a new proposed measure. Comparing the three models of reactors studied, it was observed that the mass transfer was superior to draft-tube airlift, reaching of 0.173 and kLa of 0.00904s-1. All correlations showed good fit to the experimental data (R2≥94%), and comparisons with correlations from the literature demonstrate the need for further similar studies due to shortage of data available, mainly for airlift reactors and high viscosity fluids.Keywords: bubble column, internal loop airlift, gas hold-up, kLa
Procedia PDF Downloads 2712305 Mapping Tunnelling Parameters for Global Optimization in Big Data via Dye Laser Simulation
Authors: Sahil Imtiyaz
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One of the biggest challenges has emerged from the ever-expanding, dynamic, and instantaneously changing space-Big Data; and to find a data point and inherit wisdom to this space is a hard task. In this paper, we reduce the space of big data in Hamiltonian formalism that is in concordance with Ising Model. For this formulation, we simulate the system using dye laser in FORTRAN and analyse the dynamics of the data point in energy well of rhodium atom. After mapping the photon intensity and pulse width with energy and potential we concluded that as we increase the energy there is also increase in probability of tunnelling up to some point and then it starts decreasing and then shows a randomizing behaviour. It is due to decoherence with the environment and hence there is a loss of ‘quantumness’. This interprets the efficiency parameter and the extent of quantum evolution. The results are strongly encouraging in favour of the use of ‘Topological Property’ as a source of information instead of the qubit.Keywords: big data, optimization, quantum evolution, hamiltonian, dye laser, fermionic computations
Procedia PDF Downloads 1922304 Mixed Frequency Excitation of an Electrostatically Actuated Resonator
Authors: Abdallah H. Ramini, Alwathiqbellah I. Ibrahim, Mohammad I. Younis
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We investigate experimentally and theoretically the dynamics of a capacitive resonator under mixed frequency excitation of two AC harmonic signals. The resonator is composed of a proof mass suspended by two cantilever beams. Experimental measurements are conducted using a laser Doppler Vibrometer to reveal the interesting dynamics of the system when subjected to two-source excitation. A nonlinear single-degree-of-freedom model is used for the theoretical investigation. The results reveal combination resonances of additive and subtractive type, which are shown to be promising to increase the bandwidth of the resonator near primary resonance frequency. Our results also demonstrate the ability to shift the combination resonances to much lower or much higher frequency ranges. We also demonstrate the dynamic pull-in instability under mixed frequency excitation.Keywords: electrostatically actuated resonator, multi-frequency excitation, nonlinear dynamics, AC harmonic signals
Procedia PDF Downloads 6212303 Linking Information Systems Capabilities for Service Quality: The Role of Customer Connection and Environmental Dynamism
Authors: Teng Teng, Christos Tsinopoulos
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The purpose of this research is to explore the link between IS capabilities, customer connection, and quality performance in the service context, with investigation of the impact of firm’s stable and dynamic environments. The application of Information Systems (IS) has become a significant effect on contemporary service operations. Firms invest in IS with the presumption that they will facilitate operations processes so that their performance will improve. Yet, IS resources by themselves are not sufficiently 'unique' and thus, it would be more useful and theoretically relevant to focus on the processes they affect. One such organisational process, which has attracted a lot of research attention by supply chain management scholars, is the integration of customer connection, where IS-enabled customer connection enhances communication and contact processes, and with such customer resources integration comes greater success for the firm in its abilities to develop a good understanding of customer needs and set accurate customer. Nevertheless, prior studies on IS capabilities have focused on either one specific type of technology or operationalised it as a highly aggregated concept. Moreover, although conceptual frameworks have been identified to show customer integration is valuable in service provision, there is much to learn about the practices of integrating customer resources. In this research, IS capabilities have been broken down into three dimensions based on the framework of Wade and Hulland: IT for supply chain activities (ITSCA), flexible IT infrastructure (ITINF), and IT operations shared knowledge (ITOSK); and focus on their impact on operational performance of firms in services. With this background, this paper addresses the following questions: -How do IS capabilities affect the integration of customer connection and service quality? -What is the relationship between environmental dynamism and the relationship of customer connection and service quality? A survey of 156 service establishments was conducted, and the data analysed to determine the role of customer connection in mediating the effects of IS capabilities on firms’ service quality. Confirmatory factor analysis was used to check convergent validity. There is a good model fit for the structural model. Moderating effect of environmental dynamism on the relationship of customer connection and service quality is analysed. Results show that ITSCA, ITINF, and ITOSK have a positive influence on the degree of the integration of customer connection. In addition, customer connection positively related to service quality; this relationship is further emphasised when firms work in a dynamic environment. This research takes a step towards quelling concerns about the business value of IS, contributing to the development and validation of the measurement of IS capabilities in the service operations context. Additionally, it adds to the emerging body of literature linking customer connection to the operational performance of service firms. Managers of service firms should consider the strength of the mediating role of customer connection when investing in IT-related technologies and policies. Particularly, service firms developing IS capabilities should simultaneously implement processes that encourage supply chain integration.Keywords: customer connection, environmental dynamism, information systems capabilities, service quality, service supply chain
Procedia PDF Downloads 1392302 Cancellation of Transducer Effects from Frequency Response Functions: Experimental Case Study on the Steel Plate
Authors: P. Zamani, A. Taleshi Anbouhi, M. R. Ashory, S. Mohajerzadeh, M. M. Khatibi
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Modal analysis is a developing science in the experimental evaluation of dynamic properties of the structures. Mechanical devices such as accelerometers are one of the sources of lack of quality in measuring modal testing parameters. In this paper, eliminating the accelerometer’s mass effect of the frequency response of the structure is studied. So, a strategy is used for eliminating the mass effect by using sensitivity analysis. In this method, the amount of mass change and the place to measure the structure’s response with least error in frequency correction is chosen. Experimental modal testing is carried out on a steel plate and the effect of accelerometer’s mass is omitted using this strategy. Finally, a good agreement is achieved between numerical and experimental results.Keywords: accelerometer mass, frequency response function, modal analysis, sensitivity analysis
Procedia PDF Downloads 4452301 Curriculum for the Manufacturing and Engineering Course Programs in Industries
Authors: Muhammad Yasir Latif
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Industrial Engineering and Management (IEM) is a continuous, adaptable, and dynamic branch of engineering. The purpose of this study is to use a knowledge-based course classification method to investigate four IEM educational programs in Europe. Furthermore, the relative weight of each sector was determined using the credit value of the courses. IEM-specific locations and pooled areas were the two related kinds of areas that were used. The results show that, among the four program curricula, Production Management is the specific area with the largest weight, while the specialism field of IEM has a similar weight. This method has proved to be useful for curriculum analysis. The results show that one characteristic of IEM curriculum programs is diversity in the knowledge domains related to IEM specialism. The research also highlights the importance of an organized structure for defining IEM applications, allowing benchmarking efforts, and promoting communication between academics and the IEM community.Keywords: industrial engineering and management, knowledge areas, curriculum analysis, community
Procedia PDF Downloads 172300 Impact of Financial Factors on Total Factor Productivity: Evidence from Indian Manufacturing Sector
Authors: Lopamudra D. Satpathy, Bani Chatterjee, Jitendra Mahakud
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The rapid economic growth in terms of output and investment necessitates a substantial growth of Total Factor Productivity (TFP) of firms which is an indicator of an economy’s technological change. The strong empirical relationship between financial sector development and economic growth clearly indicates that firms financing decisions do affect their levels of output via their investment decisions. Hence it establishes a linkage between the financial factors and productivity growth of the firms. To achieve the smooth and continuous economic growth over time, it is imperative to understand the financial channel that serves as one of the vital channels. The theoretical or logical argument behind this linkage is that when the internal financial capital is not sufficient enough for the investment, the firms always rely upon the external sources of finance. But due to the frictions and existence of information asymmetric behavior, it is always costlier for the firms to raise the external capital from the market, which in turn affect their investment sentiment and productivity. This kind of financial position of the firms puts heavy pressure on their productive activities. Keeping in view this theoretical background, the present study has tried to analyze the role of both external and internal financial factors (leverage, cash flow and liquidity) on the determination of total factor productivity of the firms of manufacturing industry and its sub-industries, maintaining a set of firm specific variables as control variables (size, age and disembodied technological intensity). An estimate of total factor productivity of the Indian manufacturing industry and sub-industries is computed using a semi-parametric approach, i.e., Levinsohn- Petrin method. It establishes the relationship between financial factors and productivity growth of 652 firms using a dynamic panel GMM method covering the time period between 1997-98 and 2012-13. From the econometric analyses, it has been found that the internal cash flow has a positive and significant impact on the productivity of overall manufacturing sector. The other financial factors like leverage and liquidity also play the significant role in the determination of total factor productivity of the Indian manufacturing sector. The significant role of internal cash flow on determination of firm-level productivity suggests that access to external finance is not available to Indian companies easily. Further, the negative impact of leverage on productivity could be due to the less developed bond market in India. These findings have certain implications for the policy makers to take various policy reforms to develop the external bond market and easily workout through which the financially constrained companies will be able to raise the financial capital in a cost-effective manner and would be able to influence their investments in the highly productive activities, which would help for the acceleration of economic growth.Keywords: dynamic panel, financial factors, manufacturing sector, total factor productivity
Procedia PDF Downloads 3312299 An Exploratory of the Use of English in Contemporary Society
Authors: Saksit Saengboon
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The study of English in Thailand receives comparatively little attention in the world of Englishes scholarship despite a complex and dynamic linguistic landscape. Like many countries in the region, English is used in predictable contexts, such as schools and at work. However, English is being increasingly used as a contact language among Thais and non-Thais, requiring much needed empirical attention. This study aims to address this neglected issue by examining how Thais perceive and use English in contemporary Thai society. This study explored the ways in which English has been used in public signage, mass media, especially about Thai food, and perceptions of Thais (N = 80) regarding English. Findings indicate that English in Thailand is used in a complicated manner portraying both standard and non-standard English. Thais still hold a static or traditional view of English, making it impractical, if not impossible, to have Thai English as an established variety.Keywords: Thai english, thainess in english, public signage, mass media, thai food, thai linguistic landscape
Procedia PDF Downloads 1212298 Particle Filter Implementation of a Non-Linear Dynamic Fall Model
Authors: T. Kobayashi, K. Shiba, T. Kaburagi, Y. Kurihara
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For the elderly living alone, falls can be a serious problem encountered in daily life. Some elderly people are unable to stand up without the assistance of a caregiver. They may become unconscious after a fall, which can lead to serious aftereffects such as hypothermia, dehydration, and sometimes even death. We treat the subject as an inverted pendulum and model its angle from the equilibrium position and its angular velocity. As the model is non-linear, we implement the filtering method with a particle filter which can estimate true states of the non-linear model. In order to evaluate the accuracy of the particle filter estimation results, we calculate the root mean square error (RMSE) between the estimated angle/angular velocity and the true values generated by the simulation. The experimental results give the highest accuracy RMSE of 0.0141 rad and 0.1311 rad/s for the angle and angular velocity, respectively.Keywords: fall, microwave Doppler sensor, non-linear dynamics model, particle filter
Procedia PDF Downloads 2102297 Stress Intensity Factor for Dynamic Cracking of Composite Material by X-FEM Method
Authors: S. Lecheb, A. Nour, A. Chellil, H. Mechakra, N. Hamad, H. Kebir
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The work involves develops attended by a numerical execution of the eXtend Finite Element Method premises a measurement by the fracture process cracked so many cracked plates an application will be processed for the calculation of the stress intensity factor SIF. In the first we give in statically part the distribution of stress, displacement field and strain of composite plate in two cases uncrack/edge crack, also in dynamical part the first six modes shape. Secondly, we calculate Stress Intensity Factor SIF for different orientation angle θ of central crack with length (2a=0.4mm) in plan strain condition, KI and KII are obtained for mode I and mode II respectively using X-FEM method. Finally from crack inclined involving mixed modes results, the comparison we chose dangerous inclination and the best crack angle when K is minimal.Keywords: stress intensity factor (SIF), crack orientation, glass/epoxy, natural frequencies, X-FEM
Procedia PDF Downloads 5112296 Stabilizing Additively Manufactured Superalloys at High Temperatures
Authors: Keivan Davami, Michael Munther, Lloyd Hackel
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The control of properties and material behavior by implementing thermal-mechanical processes is based on mechanical deformation and annealing according to a precise schedule that will produce a unique and stable combination of grain structure, dislocation substructure, texture, and dispersion of precipitated phases. The authors recently developed a thermal-mechanical technique to stabilize the microstructure of additively manufactured nickel-based superalloys even after exposure to high temperatures. However, the mechanism(s) that controls this stability is still under investigation. Laser peening (LP), also called laser shock peening (LSP), is a shock based (50 ns duration) post-processing technique used for extending performance levels and improving service life of critical components by developing deep levels of plastic deformation, thereby generating high density of dislocations and inducing compressive residual stresses in the surface and deep subsurface of components. These compressive residual stresses are usually accompanied with an increase in hardness and enhance the material’s resistance to surface-related failures such as creep, fatigue, contact damage, and stress corrosion cracking. While the LP process enhances the life span and durability of the material, the induced compressive residual stresses relax at high temperatures (>0.5Tm, where Tm is the absolute melting temperature), limiting the applicability of the technology. At temperatures above 0.5Tm, the compressive residual stresses relax, and yield strength begins to drop dramatically. The principal reason is the increasing rate of solid-state diffusion, which affects both the dislocations and the microstructural barriers. Dislocation configurations commonly recover by mechanisms such as climbing and recombining rapidly at high temperatures. Furthermore, precipitates coarsen, and grains grow; virtually all of the available microstructural barriers become ineffective.Our results indicate that by using “cyclic” treatments with sequential LP and annealing steps, the compressive stresses survive, and the microstructure is stable after exposure to temperatures exceeding 0.5Tm for a long period of time. When the laser peening process is combined with annealing, dislocations formed as a result of LPand precipitates formed during annealing have a complex interaction that provides further stability at high temperatures. From a scientific point of view, this research lays the groundwork for studying a variety of physical, materials science, and mechanical engineering concepts. This research could lead to metals operating at higher sustained temperatures enabling improved system efficiencies. The strengthening of metals by a variety of means (alloying, work hardening, and other processes) has been of interest for a wide range of applications. However, the mechanistic understanding of the often complex processes of interactionsbetween dislocations with solute atoms and with precipitates during plastic deformation have largely remained scattered in the literature. In this research, the elucidation of the actual mechanisms involved in the novel cyclic LP/annealing processes as a scientific pursuit is investigated through parallel studies of dislocation theory and the implementation of advanced experimental tools. The results of this research help with the validation of a novel laser processing technique for high temperature applications. This will greatly expand the applications of the laser peening technology originally devised only for temperatures lower than half of the melting temperature.Keywords: laser shock peening, mechanical properties, indentation, high temperature stability
Procedia PDF Downloads 1482295 Analysis of Some Produced Inhibitors for Corrosion of J55 Steel in NaCl Solution Saturated with CO₂
Authors: Ambrish Singh
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The corrosion inhibition performance of pyran (AP) and benzimidazole (BI) derivatives on J55 steel in 3.5% NaCl solution saturated with CO₂ was investigated by electrochemical, weight loss, surface characterization, and theoretical studies. The electrochemical studies included electrochemical impedance spectroscopy (EIS), potentiodynamic polarization (PDP), electrochemical frequency modulation (EFM), and electrochemical frequency modulation trend (EFMT). Surface characterization was done using contact angle, scanning electron microscopy (SEM), and atomic force microscopy (AFM) techniques. DFT and molecular dynamics (MD) studies were done using Gaussian and Materials Studio softwares. All the studies suggested the good inhibition by the synthesized inhibitors on J55 steel in 3.5% NaCl solution saturated with CO₂ due to the formation of a protective film on the surface. Molecular dynamic simulation was applied to search for the most stable configuration and adsorption energies for the interaction of the inhibitors with Fe (110) surface.Keywords: corrosion, inhibitor, EFM, AFM, DFT, MD
Procedia PDF Downloads 1042294 Exploring the Effectiveness of Robotic Companions Through the Use of Symbiotic Autonomous Plant Care Robots
Authors: Angelos Kaminis, Dakotah Stirnweis
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Advances in robotic technology have driven the development of improved robotic companions in the last couple decades. However, commercially available robotic companions lack the ability to create an emotional connection with their user. By developing a companion robot that has a symbiotic relationship with a plant, an element of co-dependency is introduced into the human companion robot dynamic. This companion robot, while theoretically capable of providing most of the plant’s needs, still requires human interaction for watering, moving obstacles, and solar panel cleaning. To facilitate the interaction between human and robot, the robot is capable of limited auditory and visual communication to help express its and the plant’s needs. This paper seeks to fully describe the Autonomous Plant Care Robot system and its symbiotic relationship with its botanical ward and the plant and robot’s dependent relationship with their owner.Keywords: symbiotic, robotics, autonomous, plant-care, companion
Procedia PDF Downloads 1432293 Cities Under Pressure: Unraveling Urban Resilience Challenges
Authors: Sherine S. Aly, Fahd A. Hemeida, Mohamed A. Elshamy
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In the face of rapid urbanization and the myriad challenges posed by climate change, population growth, and socio-economic disparities, fostering urban resilience has become paramount. This abstract offers a comprehensive overview of the study on "Urban Resilience Challenges," exploring the background, methodologies, major findings, and concluding insights. The paper unveils a spectrum of challenges encompassing environmental stressors and deep-seated socio-economic issues, such as unequal access to resources and opportunities. Emphasizing their interconnected nature, the study underscores the imperative for holistic and integrated approaches to urban resilience, recognizing the intricate web of factors shaping the urban landscape. Urbanization has witnessed an unprecedented surge, transforming cities into dynamic and complex entities. With this growth, however, comes an array of challenges that threaten the sustainability and resilience of urban environments. This study seeks to unravel the multifaceted urban resilience challenges, exploring their origins and implications for contemporary cities. Cities serve as hubs of economic, social, and cultural activities, attracting diverse populations seeking opportunities and a higher quality of life. However, the urban fabric is increasingly strained by climate-related events, infrastructure vulnerabilities, and social inequalities. Understanding the nuances of these challenges is crucial for developing strategies that enhance urban resilience and ensure the longevity of cities as vibrant and adaptive entities. This paper endeavors to discern strategic guidelines for enhancing urban resilience amidst the dynamic challenges posed by rapid urbanization. The study aims to distill actionable insights that can inform strategic approaches. Guiding the formulation of effective strategies to fortify cities against multifaceted pressures. The study employs a multifaceted approach to dissect urban resilience challenges. A qualitative method will be employed, including comprehensive literature reviews and data analysis of urban vulnerabilities that provided valuable insights into the lived experiences of resilience challenges in diverse urban settings. In conclusion, this study underscores the urgency of addressing urban resilience challenges to ensure the sustained vitality of cities worldwide. The interconnected nature of these challenges necessitates a paradigm shift in urban planning and governance. By adopting holistic strategies that integrate environmental, social, and economic considerations, cities can navigate the complexities of the 21st century. The findings provide a roadmap for policymakers, planners, and communities to collaboratively forge resilient urban futures that withstand the challenges of an ever-evolving urban landscape.Keywords: resilient principles, risk management, sustainable cities, urban resilience
Procedia PDF Downloads 532292 Dynamic Soil Structure Interaction in Buildings
Authors: Shreya Thusoo, Karan Modi, Ankit Kumar Jha, Rajesh Kumar
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Since the evolution of computational tools and simulation software, there has been considerable increase in research on Soil Structure Interaction (SSI) to decrease the computational time and increase accuracy in the results. To aid the designer with a proper understanding of the response of structure in different soil types, the presented paper compares the deformation, shear stress, acceleration and other parameters of multi-storey building for a specific input ground motion using Response-spectrum Analysis (RSA) method. The response of all the models of different heights have been compared in different soil types. Finite Element Simulation software, ANSYS, has been used for all the computational purposes. Overall, higher response is observed with SSI, while it increases with decreasing stiffness of soil.Keywords: soil-structure interaction, response spectrum, analysis, finite element method, multi-storey buildings
Procedia PDF Downloads 4772291 Does "R and D" Investment Drive Economic Growth? Evidence from Africa
Authors: Boopen Seetanah, R. V. Sannassee, Sheereen Fauzel, Robin Nunkoo
Abstract:
The bulk of research on the impact of research and development (R&D) has been carried out in developed economies where the intensity of R&D expenditure has been relatively high and stable for many years. However, there is a paucity of similar studies in developing countries. In this paper, we provide empirical estimates of the impact of R&D investment on economic growth in a developing African economy (Mauritius) where R&D expenditure intensity has been low initially, but rising, albeit moderately in recent years. Using a dynamic time series analysis over the period 1980 to 2014 in a Vector Autoregressive framework, R & D is shown to have a positive and significant effect on the economic progress of the island, although the impact is considerably less when compared to both other ingredients of growth and also to reported elasticities fromdeveloped economies . Interestingly, there is evidence of bicausality between R & D and growth. furthermore, R & D positively impacts on both domestic and foreign investment, suggesting the possibilities of indirect effects.Keywords: R & D, VECM, Africa, Mauritius
Procedia PDF Downloads 4352290 Evolution of Classroom Languaging in Multilingual Contexts: Challenges and Prospects
Authors: Jabulani Sibanda, Clemence Chikiwa
Abstract:
This paper traces diverse language practices representative of equally diverse conceptions of language. To be dynamic with languaging practices, one needs to appreciate nuanced languaging practices, their challenges, prospects, and opportunities. The paper presents what we envision as three major conceptions of language that give impetus to diverse language practices. It examines theoretical models of the bilingual mental lexicon and how they inform language practices. The paper explores classroom languaging practices that have been promulgated and experimented with. The paper advocates the deployment of multisensory semiotic systems to complement linguistic classroom communication and the acknowledgement of learners’ linguistic and semiotic resources as valid in the learning enterprise. It recommends the enactment of specific clauses on language in education policies and curriculum documents that empower classroom interactants to exercise discretion in languaging practices.Keywords: languaging, monolingual, multilingual, semiotic and linguistic repertoire
Procedia PDF Downloads 64