Search results for: love wave
1477 A Study of Standing-Wave Thermoacoustic Refrigerator
Authors: Patcharin Saechan, Isares Dhuchakallaya
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Thermoacoustic refrigerator is a cooling device which uses the acoustic waves to produce the cooling effect. The aim of this paper is to explore the experimental and numerical feasibility of a standing-wave thermoacoustic refrigerator. The effects of the stack length, position of stack and operating frequency on the cooling performance are carried out. The circular pore stacks are tested under the atmospheric pressure. A low-cost loudspeaker is used as an acoustic driver. The results show that the location of stack installed in resonator tube has a greater effect on the cooling performance than the stack length and operating frequency, respectively. The temperature difference across the ends of the stack can be generated up to 13.7°C, and the temperature of cold-end is dropped down by 5.3°C from the ambient temperature.Keywords: cooling performance, refrigerator, standing-wave, thermoacoustics
Procedia PDF Downloads 1881476 The Relations between Seismic Results and Groundwater near the Gokpinar Damp Area, Denizli, Turkey
Authors: Mahmud Gungor, Ali Aydin, Erdal Akyol, Suat Tasdelen
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The understanding of geotechnical characteristics of near-surface material and the effects of the groundwater is very important problem in such as site studies. For showing the relations between seismic data and groundwater we selected about 25 km2 as the study area. It has been presented which is a detailed work of seismic data and groundwater depths of Gokpinar Damp area. Seismic waves velocity (Vp and Vs) are very important parameters showing the soil properties. The seismic records were used the method of the multichannel analysis of surface waves near area of Gokpinar Damp area. Sixty sites in this area have been investigated with survey lines about 60 m in length. MASW (Multichannel analysis of surface wave) method has been used to generate one-dimensional shear wave velocity profile at locations. These shear wave velocities are used to estimate equivalent shear wave velocity in the study area at every 2 and 5 m intervals up to a depth of 45 m. Levels of equivalent shear wave velocity of soil are used the classified of the study area. After the results of the study, it must be considered as components of urban planning and building design of Gokpinar Damp area, Denizli and the application and use of these results should be required and enforced by municipal authorities.Keywords: seismic data, Gokpinar Damp, urban planning, Denizli
Procedia PDF Downloads 2831475 A Low-Power Two-Stage Seismic Sensor Scheme for Earthquake Early Warning System
Authors: Arvind Srivastav, Tarun Kanti Bhattacharyya
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The north-eastern, Himalayan, and Eastern Ghats Belt of India comprise of earthquake-prone, remote, and hilly terrains. Earthquakes have caused enormous damages in these regions in the past. A wireless sensor network based earthquake early warning system (EEWS) is being developed to mitigate the damages caused by earthquakes. It consists of sensor nodes, distributed over the region, that perform majority voting of the output of the seismic sensors in the vicinity, and relay a message to a base station to alert the residents when an earthquake is detected. At the heart of the EEWS is a low-power two-stage seismic sensor that continuously tracks seismic events from incoming three-axis accelerometer signal at the first-stage, and, in the presence of a seismic event, triggers the second-stage P-wave detector that detects the onset of P-wave in an earthquake event. The parameters of the P-wave detector have been optimized for minimizing detection time and maximizing the accuracy of detection.Working of the sensor scheme has been verified with seven earthquakes data retrieved from IRIS. In all test cases, the scheme detected the onset of P-wave accurately. Also, it has been established that the P-wave onset detection time reduces linearly with the sampling rate. It has been verified with test data; the detection time for data sampled at 10Hz was around 2 seconds which reduced to 0.3 second for the data sampled at 100Hz.Keywords: earthquake early warning system, EEWS, STA/LTA, polarization, wavelet, event detector, P-wave detector
Procedia PDF Downloads 1731474 An Interdisciplinary Approach to Investigating Style: A Case Study of a Chinese Translation of Gilbert’s (2006) Eat Pray Love
Authors: Elaine Y. L. Ng
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Elizabeth Gilbert’s (2006) biography Eat, Pray, Love describes her travels to Italy, India, and Indonesia after a painful divorce. The author’s experiences with love, loss, search for happiness, and meaning have resonated with a huge readership. As regards the translation of Gilbert’s (2006) Eat, Pray, Love into Chinese, it was first translated by a Taiwanese translator He Pei-Hua and published in Taiwan in 2007 by Make Boluo Wenhua Chubanshe with the fairly catching title “Enjoy! Traveling Alone.” The same translation was translocated to China, republished in simplified Chinese characters by Shanxi Shifan Daxue Chubanshe in 2008 and renamed in China, entitled “To Be a Girl for the Whole Life.” Later on, the same translation in simplified Chinese characters was reprinted by Hunan Wenyi Chubanshe in 2013. This study employs Munday’s (2002) systemic model for descriptive translation studies to investigate the translation of Gilbert’s (2006) Eat, Pray, Love into Chinese by the Taiwanese translator Hu Pei-Hua. It employs an interdisciplinary approach, combining systemic functional linguistics and corpus stylistics with sociohistorical research within a descriptive framework to study the translator’s discursive presence in the text. The research consists of three phases. The first phase is to locate the target text within its socio-cultural context. The target-text context concerning the para-texts, readers’ responses, and the publishers’ orientation will be explored. The second phase is to compare the source text and the target text for the categorization of translation shifts by using the methodological tools of systemic functional linguistics and corpus stylistics. The investigation concerns the rendering of mental clauses and speech and thought presentation. The final phase is an explanation of the causes of translation shifts. The linguistic findings are related to the extra-textual information collected in an effort to ascertain the motivations behind the translator’s choices. There exist sets of possible factors that may have contributed to shaping the textual features of the given translation within a specific socio-cultural context. The study finds that the translator generally reproduces the mental clauses and speech and thought presentation closely according to the original. Nevertheless, the language of the translation has been widely criticized to be unidiomatic and stiff, losing the elegance of the original. In addition, the several Chinese translations of the given text produced by one Taiwanese and two Chinese publishers are basically the same. They are repackaged slightly differently, mainly with the change of the book cover and its captions for each version. By relating the textual findings to the extra-textual data of the study, it is argued that the popularity of the Chinese translation of Gilbert’s (2006) Eat, Pray, Love may not be attributed to the quality of the translation. Instead, it may have to do with the way the work is promoted strategically by the social media manipulated by the four e-bookstores promoting and selling the book online in China.Keywords: chinese translation of eat pray love, corpus stylistics, motivations for translation shifts, systemic approach to translation studies
Procedia PDF Downloads 1691473 Wave Propagation In Functionally Graded Lattice Structures Under Impact Loads
Authors: Mahmood Heshmati, Farhang Daneshmand
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Material scientists and engineers have introduced novel materials with complex geometries due to the recent technological advances and promotion of manufacturing methods. Among them, lattice structures with graded architectures denoted by functionally graded porous materials (FGPMs) have been developed to optimize the structural response. FGPMs are achieved by tailoring the size and density of the internal pores in one or more directions that lead to the desired mechanical properties and structural responses. Also, FGPMs provide more flexible transition and the possibility of designing and fabricating structural elements with complex and variable properties. In this paper, wave propagation in lattice structures with functionally graded (FG) porosity is investigated in order to examine the ability of shock absorbing effect. The behavior of FG porous beams with different porosity distributions under impact load and the effects of porosity distribution and porosity content on the wave speed are studied. Important conclusions are made, along with a discussion of the future scope of studies on FGPMs structures.Keywords: functionally graded, porous materials, wave propagation, impact load, finite element
Procedia PDF Downloads 771472 Time-Domain Simulations of the Coupled Dynamics of Surface Riding Wave Energy Converter
Authors: Chungkuk Jin, Moo-Hyun Kim, HeonYong Kang
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A surface riding (SR) wave energy converter (WEC) is designed and its feasibility and performance are numerically simulated by the author-developed floater-mooring-magnet-electromagnetics fully-coupled dynamic analysis computer program. The biggest advantage of the SR-WEC is that the performance is equally effective even in low sea states and its structural robustness is greatly improved by simply riding along the wave surface compared to other existing WECs. By the numerical simulations and actuator testing, it is clearly demonstrated that the concept works and through the optimization process, its efficiency can be improved.Keywords: computer simulation, electromagnetics fully-coupled dynamics, floater-mooring-magnet, optimization, performance evaluation, surface riding, WEC
Procedia PDF Downloads 1401471 Impairments Correction of Six-Port Based Millimeter-Wave Radar
Authors: Dan Ohev Zion, Alon Cohen
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In recent years, the presence of short-range millimeter-wave radar in civil application has increased significantly. Autonomous driving, security, 3D imaging and high data rate communication systems are a few examples. The next challenge is the integration inside small form-factor devices, such as smartphones (e.g. gesture recognition). The main challenge is implementation of a truly low-power, low-complexity high-resolution radar. The most popular approach is the Frequency Modulated Continuous Wave (FMCW) radar, with an analog multiplication front-end. In this paper, we present an approach for adaptive estimation and correction of impairments of such front-end, specifically implemented using the Six-Port Device (SPD) as the multiplier element. The proposed algorithm was simulated and implemented on a 60 GHz radar lab prototype.Keywords: radar, FMCW Radar, IQ mismatch, six port
Procedia PDF Downloads 1471470 Influence of Corrugation and Loosely Bonded Interface on the Propagation of Torsional Wave Propagation in a Viscoelastic Layer
Authors: Amrita Das, Abhishek Kumar Singh
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The present paper calibrates the efficacy of corrugated and loosely bonded common interface of a viscoelastic layer and a dry sandy Gibson half-space on the propagation of torsional surface wave. Using suitable boundary conditions, the dispersion relation for the concerned problem is deduced in complex form. Numerical computation of the real part of the obtained dispersion relation gives the dispersion curve whereas the imaginary part bestows the damping curves. The use of Whittaker’s function and Bessel’s functions are among the major concerns of the paper. The investigation of the influence of the affecting parameters viz. heterogeneities, sandiness, Biot’s gravity parameter, initial stresses, loosely bonded interface, corrugation and internal friction on the phase velocity as well as damped velocity of torsional wave, through numerical discussion and graphical illustration, is among the major highlights of the current study.Keywords: corrugation, dry sandy Gibson half-space, loosely bonded interface, torsional wave, viscoelastic layer
Procedia PDF Downloads 3171469 Kinetic Alfvén Wave Localization and Turbulent Spectrum
Authors: Anju Kumari, R. P. Sharma
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The localization of Kinetic Alfvén Wave (KAW) caused by finite amplitude background density fluctuations has been studied in intermediate beta plasma. KAW breaks up into localized large amplitude structures when perturbed by MHD fluctuations of the medium which are in the form of magnetosonic waves. Numerical simulation has been performed to analyse the localized structures and resulting turbulent spectrum of KAW applicable to magnetopause. Simulation results reveal that power spectrum deviates from Kolmogorov scaling at the transverse size of KAW, equal to ion gyroradius. Steepening of power spectrum at shorter wavelengths may be accountable for heating and acceleration of the plasma particles. The obtained results are compared with observations collected from the THEMIS spacecraft in magnetopause.Keywords: Kinetic Alfvén Wave (KAW), localization, turbulence, turbulent spectrum
Procedia PDF Downloads 4881468 Simultaneous Measurement of Wave Pressure and Wind Speed with the Specific Instrument and the Unit of Measurement Description
Authors: Branimir Jurun, Elza Jurun
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The focus of this paper is the description of an instrument called 'Quattuor 45' and defining of wave pressure measurement. Special attention is given to measurement of wave pressure created by the wind speed increasing obtained with the instrument 'Quattuor 45' in the investigated area. The study begins with respect to theoretical attitudes and numerous up to date investigations related to the waves approaching the coast. The detailed schematic view of the instrument is enriched with pictures from ground plan and side view. Horizontal stability of the instrument is achieved by mooring which relies on two concrete blocks. Vertical wave peak monitoring is ensured by one float above the instrument. The synthesis of horizontal stability and vertical wave peak monitoring allows to create a representative database for wave pressure measuring. Instrument ‘Quattuor 45' is named according to the way the database is received. Namely, the electronic part of the instrument consists of the main chip ‘Arduino', its memory, four load cells with the appropriate modules and the wind speed sensor 'Anemometers'. The 'Arduino' chip is programmed to store two data from each load cell and two data from the anemometer on SD card each second. The next part of the research is dedicated to data processing. All measured results are stored automatically in the database and after that detailed processing is carried out in the MS Excel. The result of the wave pressure measurement is synthesized by the unit of measurement kN/m². This paper also suggests a graphical presentation of the results by multi-line graph. The wave pressure is presented on the left vertical axis, while the wind speed is shown on the right vertical axis. The time of measurement is displayed on the horizontal axis. The paper proposes an algorithm for wind speed measurements showing the results for two characteristic winds in the Adriatic Sea, called 'Bura' and 'Jugo'. The first of them is the northern wind that reaches high speeds, causing low and extremely steep waves, where the pressure of the wave is relatively weak. On the other hand, the southern wind 'Jugo' has a lower speed than the northern wind, but due to its constant duration and constant speed maintenance, it causes extremely long and high waves that cause extremely high wave pressure.Keywords: instrument, measuring unit, waves pressure metering, wind seed measurement
Procedia PDF Downloads 1911467 Plastic Pipe Defect Detection Using Nonlinear Acoustic Modulation
Authors: Gigih Priyandoko, Mohd Fairusham Ghazali, Tan Siew Fun
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This paper discusses about the defect detection of plastic pipe by using nonlinear acoustic wave modulation method. It is a sensitive method for damage detection and it is based on the propagation of high frequency acoustic waves in plastic pipe with low frequency excitation. The plastic pipe is excited simultaneously with a slow amplitude modulated vibration pumping wave and a constant amplitude probing wave. The frequency of both the excitation signals coincides with the resonances of the plastic pipe. A PVP pipe is used as the specimen as it is commonly used for the conveyance of liquid in many fields. The results obtained are being observed and the difference between uncracked specimen and cracked specimen can be distinguished clearly.Keywords: plastic pipe, defect detection, nonlinear acoustic modulation, excitation
Procedia PDF Downloads 4441466 Nonlinear Propagation of Acoustic Soliton Waves in Dense Quantum Electron-Positron Magnetoplasma
Authors: A. Abdikian
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Propagation of nonlinear acoustic wave in dense electron-positron (e-p) plasmas in the presence of an external magnetic field and stationary ions (to neutralize the plasma background) is studied. By means of the quantum hydrodynamics model and applying the reductive perturbation method, the Zakharov-Kuznetsov equation is derived. Using the bifurcation theory of planar dynamical systems, the compressive structure of electrostatic solitary wave and periodic travelling waves is found. The numerical results show how the ion density ratio, the ion cyclotron frequency, and the direction cosines of the wave vector affect the nonlinear electrostatic travelling waves. The obtained results may be useful to better understand the obliquely nonlinear electrostatic travelling wave of small amplitude localized structures in dense magnetized quantum e-p plasmas and may be applicable to study the particle and energy transport mechanism in compact stars such as the interior of massive white dwarfs etc.Keywords: bifurcation theory, phase portrait, magnetized electron-positron plasma, the Zakharov-Kuznetsov equation
Procedia PDF Downloads 2371465 Storms Dynamics in the Black Sea in the Context of the Climate Changes
Authors: Eugen Rusu
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The objective of the work proposed is to perform an analysis of the wave conditions in the Black Sea basin. This is especially focused on the spatial and temporal occurrences and on the dynamics of the most extreme storms in the context of the climate changes. A numerical modelling system, based on the spectral phase averaged wave model SWAN, has been implemented and validated against both in situ measurements and remotely sensed data, all along the sea. Moreover, a successive correction method for the assimilation of the satellite data has been associated with the wave modelling system. This is based on the optimal interpolation of the satellite data. Previous studies show that the process of data assimilation improves considerably the reliability of the results provided by the modelling system. This especially concerns the most sensitive cases from the point of view of the accuracy of the wave predictions, as the extreme storm situations are. Following this numerical approach, it has to be highlighted that the results provided by the wave modelling system above described are in general in line with those provided by some similar wave prediction systems implemented in enclosed or semi-enclosed sea basins. Simulations of this wave modelling system with data assimilation have been performed for the 30-year period 1987-2016. Considering this database, the next step was to analyze the intensity and the dynamics of the higher storms encountered in this period. According to the data resulted from the model simulations, the western side of the sea is considerably more energetic than the rest of the basin. In this western region, regular strong storms provide usually significant wave heights greater than 8m. This may lead to maximum wave heights even greater than 15m. Such regular strong storms may occur several times in one year, usually in the wintertime, or in late autumn, and it can be noticed that their frequency becomes higher in the last decade. As regards the case of the most extreme storms, significant wave heights greater than 10m and maximum wave heights close to 20m (and even greater) may occur. Such extreme storms, which in the past were noticed only once in four or five years, are more recent to be faced almost every year in the Black Sea, and this seems to be a consequence of the climate changes. The analysis performed included also the dynamics of the monthly and annual significant wave height maxima as well as the identification of the most probable spatial and temporal occurrences of the extreme storm events. Finally, it can be concluded that the present work provides valuable information related to the characteristics of the storm conditions and on their dynamics in the Black Sea. This environment is currently subjected to high navigation traffic and intense offshore and nearshore activities and the strong storms that systematically occur may produce accidents with very serious consequences.Keywords: Black Sea, extreme storms, SWAN simulations, waves
Procedia PDF Downloads 2391464 Ankh Key Broadband Array Antenna for 5G Applications
Authors: Noha M. Rashad, W. Swelam, M. H. Abd ElAzeem
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A simple design of array antenna is presented in this paper, supporting millimeter wave applications which can be used in short range wireless communications such as 5G applications. This design enhances the use of V-band, according to IEEE standards, as the antenna works in the 70 GHz band with bandwidth more than 11 GHz and peak gain more than 13 dBi. The design is simulated using different numerical techniques achieving a very good agreement.Keywords: 5G technology, array antenna, microstrip, millimeter wave
Procedia PDF Downloads 2981463 Smart Brain Wave Sensor for Paralyzed- a Real Time Implementation
Authors: U.B Mahadevswamy UBM, Siraj Ahmed Siraj
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As the title of the paper indicates about brainwaves and its uses for various applications based on their frequencies and different parameters which can be implemented as real time application with the title a smart brain wave sensor system for paralyzed patients. Brain wave sensing is to detect a person's mental status. The purpose of brain wave sensing is to give exact treatment to paralyzed patients. The data or signal is obtained from the brainwaves sensing band. This data are converted as object files using Visual Basics. The processed data is further sent to Arduino which has the human's behavioral aspects like emotions, sensations, feelings, and desires. The proposed device can sense human brainwaves and detect the percentage of paralysis that the person is suffering. The advantage of this paper is to give a real-time smart sensor device for paralyzed patients with paralysis percentage for their exact treatment. Keywords:-Brainwave sensor, BMI, Brain scan, EEG, MCH.Keywords: Keywords:-Brainwave sensor , BMI, Brain scan, EEG, MCH
Procedia PDF Downloads 1481462 Hydrodynamic Performance of a Moored Barge in Irregular Wave
Authors: Srinivasan Chandrasekaran, Shihas A. Khader
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Motion response of floating structures is of great concern in marine engineering. Nonlinearity is an inherent property of any floating bodies subjected to irregular waves. These floating structures are continuously subjected to environmental loadings from wave, current, wind etc. This can result in undesirable motions of the vessel which may challenge the operability. For a floating body to remain in its position, it should be able to induce a restoring force when displaced. Mooring is provided to enable this restoring force. This paper discuss the hydrodynamic performance and motion characteristics of an 8 point spread mooring system applied to a pipe laying barge operating in the West African sea. The modelling of the barge is done using a computer aided-design (CAD) software RHINOCEROS. Irregular waves are generated using a suitable wave spectrum. Both frequency domain and time domain analysis is done. Numerical simulations based on potential theory are carried out to find the responses and hydrodynamic performance of the barge in both free floating as well as moored conditions. Initially, potential flow frequency domain analysis is done to obtain the Response Amplitude Operator (RAO) which gives an idea about the structural motion in free floating state. RAOs for different wave headings are analyzed. In the following step, a time domain analysis is carried out to obtain the responses of the structure in the moored condition. In this study, wave induced motions are only taken into consideration. Wind and current loads are ruled out and shall be included in future studies. For the current study, 5000 seconds simulation is taken. The results represent wave-induced motion responses, mooring line tensions and identifies critical mooring lines.Keywords: irregular wave, moored barge, time domain analysis, numerical simulation
Procedia PDF Downloads 2481461 Physically Informed Kernels for Wave Loading Prediction
Authors: Daniel James Pitchforth, Timothy James Rogers, Ulf Tyge Tygesen, Elizabeth Jane Cross
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Wave loading is a primary cause of fatigue within offshore structures and its quantification presents a challenging and important subtask within the SHM framework. The accurate representation of physics in such environments is difficult, however, driving the development of data-driven techniques in recent years. Within many industrial applications, empirical laws remain the preferred method of wave loading prediction due to their low computational cost and ease of implementation. This paper aims to develop an approach that combines data-driven Gaussian process models with physical empirical solutions for wave loading, including Morison’s Equation. The aim here is to incorporate physics directly into the covariance function (kernel) of the Gaussian process, enforcing derived behaviors whilst still allowing enough flexibility to account for phenomena such as vortex shedding, which may not be represented within the empirical laws. The combined approach has a number of advantages, including improved performance over either component used independently and interpretable hyperparameters.Keywords: offshore structures, Gaussian processes, Physics informed machine learning, Kernel design
Procedia PDF Downloads 1851460 Sensitive Determination of Copper(II) by Square Wave Anodic Stripping Voltammetry with Tetracarbonylmolybdenum(0) Multiwalled Carbon Nanotube Paste Electrode
Authors: Illyas Md Isa, Mohamad Idris Saidin, Mustaffa Ahmad, Norhayati Hashim
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A highly selective and sensitive carbon paste electrode modified with multiwall carbon nanotubes and 2,6–diacetylpyridine-di-(1R)–(-)–fenchone diazine tetracarbonylmolybdenum(0) complex was used for determination of trace amounts of Cu(II) using square wave anodic stripping voltammetry (SWASV). The influences of experimental variables on the proposed electrode such as pH, supporting electrolyte, preconcentration potential and time, and square wave parameters were investigated. Under optimal conditions, the proposed electrode showed a linear relationship with concentration in the range of 1.0 × 10–10 to 1.0 × 10– 6 M Cu(II) with a limit of detection 8.0 × 10–11 M. The relative standard deviation (n = 5) for a solution containing 1.0 × 10– 6 M of Cu(II) was 0.036. The presence of various cations (in 10 and 100-folds concentration) did not interfere. Electrochemical impedance spectroscopy (EIS) showed that the charge transfer at the electrode-solution interface was favourable. The proposed electrode was applied for the determination of Cu(II) in several water samples. Results agreed very well with those obtained by inductively coupled plasma-optical emission spectrometry. The modified electrode was then proposed as an alternative for determination of Cu(II).Keywords: chemically modified electrode, Cu(II), square wave anodic stripping voltammetry, tetracarbonylmolybdenum(0)
Procedia PDF Downloads 2651459 The Impact of Brand Hate and Love: A Thematic Analysis of Online Emotions in Response to Disney’s Corporate Activism
Authors: Roxana D. Maiorescu-Murphy
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Companies have recently embraced political activism as an alleged responsibility toward the communities they operate in. As a result of its recency, there is little understanding of the impact of corporate activism on consumers. In addition, embracing corporate activism engenders polarizing opinions, potentially leading to a crisis of morality shown in past literature to flourish in online settings. The present study contributes to the literature on communication management, which currently lacks research on stakeholder perceptions toward corporate activism in general and from the perspective of the stakeholders’ emotions of brand hate versus a love that they display before a specific corporate act of activism. For this purpose, the study analyzed online reactions on Twitter following Disney’s stance against Florida’s House Bill 1577 enacted in April 2022. Dubbed the “Don’t Say Gay Bill” by the left wing and the “Parental Rights Bill” by the conservative movement, the legislation triggered polarizing opinions in society and among Disney’s stakeholders, as the company announce it was taking action against it. Given the scarcity of research on corporate political activism and crises of morality, the current study enacted the case study methodology. Consequently, it answered to the research questions of how online stakeholders responded to Disney’s stance as well as why they formed such an opinion. The data were collected from Twitter over a seven-day period of analysis, namely from March 28- April 3, 2022. The period of analysis started on the day Disney announced its stance (March 28, 2022) until the reactions to its announcement petered out significantly (April 3, 2022). The final sample of analysis consisted of N=1,344 and represented Twitter comments in response to the company’s political announcement. The data were analyzed using the grounded theory methodology, which implied multiple exposures to the text and the undertaking of an inductive-deductive approach that led to the emergence of several recurrent themes. The findings revealed that the stakeholders’ prior emotions toward the company (brand hate versus brand love) did not play a greater role in their (dis)agreement with the latter’s activism than the users’ political stances. Specifically, whether they despised or hated Disney prior to this incident was less significant than their personal political stances. Above all, users were more inclined to transition from brand love to brand hate and vice versa based on the political side they viewed Disney to fall under.Keywords: corporate political advocacy, crisis management, brand hate, brand love
Procedia PDF Downloads 1081458 Prophet and Philosopher Mohammed: A Precursor of Feminism
Authors: Mohammad Mozammel Haque
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That feminism is nothing but the name of a belief that women should have the same rights as men needs no telling. The history of modern western feminism is divided into three waves and each is described as dealing with different aspects of the same feminist issues. The first wave refers to the movement of the 19th through early 20th centuries, which dealt mainly with suffrage, working conditions and educational rights for women. The second wave (1960s-1980s) dealt with the inequality of laws and the role of women in society. The third wave (late 1980s-early 2000s) is seen as both a continuation of the second wave and a response to the perceived failures. Mary Wollstonecraft struggled for the emancipation and freedom of the women of Europe, Begum Rokeya brought about revolution for the women of the East and West Bengal, Jeremy Bentham wrote for the independence of women in England. But if feminism refers to the movement of giving women what they deserve, then it won’t be an overstatement to state that Mohammad is the precursor of what we call feminism. This paper investigates the background of official starting of feminism, and also the backdrop of the women of Muhammad’s time. The article, besides showing that this great prophet and philosopher firstly brought about a movement for the education and rights of women and took them out of grave where they were buried alive, also delineates Mohammedan endeavours he attempted to give the women what they ought to have.Keywords: education, equality, feminism, precursor
Procedia PDF Downloads 4911457 Nonlinear Modelling of Sloshing Waves and Solitary Waves in Shallow Basins
Authors: Mohammad R. Jalali, Mohammad M. Jalali
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The earliest theories of sloshing waves and solitary waves based on potential theory idealisations and irrotational flow have been extended to be applicable to more realistic domains. To this end, the computational fluid dynamics (CFD) methods are widely used. Three-dimensional CFD methods such as Navier-Stokes solvers with volume of fluid treatment of the free surface and Navier-Stokes solvers with mappings of the free surface inherently impose high computational expense; therefore, considerable effort has gone into developing depth-averaged approaches. Examples of such approaches include Green–Naghdi (GN) equations. In Cartesian system, GN velocity profile depends on horizontal directions, x-direction and y-direction. The effect of vertical direction (z-direction) is also taken into consideration by applying weighting function in approximation. GN theory considers the effect of vertical acceleration and the consequent non-hydrostatic pressure. Moreover, in GN theory, the flow is rotational. The present study illustrates the application of GN equations to propagation of sloshing waves and solitary waves. For this purpose, GN equations solver is verified for the benchmark tests of Gaussian hump sloshing and solitary wave propagation in shallow basins. Analysis of the free surface sloshing of even harmonic components of an initial Gaussian hump demonstrates that the GN model gives predictions in satisfactory agreement with the linear analytical solutions. Discrepancies between the GN predictions and the linear analytical solutions arise from the effect of wave nonlinearities arising from the wave amplitude itself and wave-wave interactions. Numerically predicted solitary wave propagation indicates that the GN model produces simulations in good agreement with the analytical solution of the linearised wave theory. Comparison between the GN model numerical prediction and the result from perturbation analysis confirms that nonlinear interaction between solitary wave and a solid wall is satisfactorilly modelled. Moreover, solitary wave propagation at an angle to the x-axis and the interaction of solitary waves with each other are conducted to validate the developed model.Keywords: Green–Naghdi equations, nonlinearity, numerical prediction, sloshing waves, solitary waves
Procedia PDF Downloads 2781456 A Dislocation-Based Explanation to Quasi-Elastic Release in Shock Loaded Aluminum
Authors: Song L. Yao, Ji D. Yu, Xiao Y. Pei
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An explanation is introduced to study the quasi-elastic release phenomenon in shock compressed aluminum. A dislocation-based model, taking into account of dislocation substructures and evolutions, is applied to simulate the elastic-plastic response of both single crystal and polycrystalline aluminum. Simulated results indicate that dislocation immobilization during dynamic deformation results in a smooth increase of yield stress, which leads to the quasi-elastic release. While the generation of dislocations caused by plastic release wave results in the appearance of transition point between the quasi-elastic release and the plastic release in the profile. The quantities of calculated shear strength and dislocation density are in accordance with experimental result, which demonstrates the accuracy of our simulations.Keywords: dislocation density, quasi-elastic release, wave profile, shock wave
Procedia PDF Downloads 2741455 Numerical Modeling of Wave Run-Up in Shallow Water Flows Using Moving Wet/Dry Interfaces
Authors: Alia Alghosoun, Michael Herty, Mohammed Seaid
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We present a new class of numerical techniques to solve shallow water flows over dry areas including run-up. Many recent investigations on wave run-up in coastal areas are based on the well-known shallow water equations. Numerical simulations have also performed to understand the effects of several factors on tsunami wave impact and run-up in the presence of coastal areas. In all these simulations the shallow water equations are solved in entire domain including dry areas and special treatments are used for numerical solution of singularities at these dry regions. In the present study we propose a new method to deal with these difficulties by reformulating the shallow water equations into a new system to be solved only in the wetted domain. The system is obtained by a change in the coordinates leading to a set of equations in a moving domain for which the wet/dry interface is the reconstructed using the wave speed. To solve the new system we present a finite volume method of Lax-Friedrich type along with a modified method of characteristics. The method is well-balanced and accurately resolves dam-break problems over dry areas.Keywords: dam-break problems, finite volume method, run-up waves, shallow water flows, wet/dry interfaces
Procedia PDF Downloads 1431454 Exact Solutions of K(N,N)-Type Equations Using Jacobi Elliptic Functions
Authors: Edamana Krishnan, Khalil Al-Ghafri
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In this paper, modified K(n,n) and K(n+1,n+1) equations have been solved using mapping methods which give a variety of solutions in terms of Jacobi elliptic functions. The solutions when m approaches 0 and 1, with m as the modulus of the JEFs have also been deduced. The role of constraint conditions has been discussed.Keywords: travelling wave solutions, solitary wave solutions, compactons, Jacobi elliptic functions, mapping methods
Procedia PDF Downloads 3011453 Multichannel Analysis of the Surface Waves of Earth Materials in Some Parts of Lagos State, Nigeria
Authors: R. B. Adegbola, K. F. Oyedele, L. Adeoti
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We present a method that utilizes Multi-channel Analysis of Surface Waves, which was used to measure shear wave velocities with a view to establishing the probable causes of road failure, subsidence and weakening of structures in some Local Government Area, Lagos, Nigeria. Multi channel Analysis of Surface waves (MASW) data were acquired using 24-channel seismograph. The acquired data were processed and transformed into two-dimensional (2-D) structure reflective of depth and surface wave velocity distribution within a depth of 0–15m beneath the surface using SURFSEIS software. The shear wave velocity data were compared with other geophysical/borehole data that were acquired along the same profile. The comparison and correlation illustrates the accuracy and consistency of MASW derived-shear wave velocity profiles. Rigidity modulus and N-value were also generated. The study showed that the low velocity/very low velocity are reflective of organic clay/peat materials and thus likely responsible for the failed, subsidence/weakening of structures within the study areas.Keywords: seismograph, road failure, rigidity modulus, N-value, subsidence
Procedia PDF Downloads 3571452 Investigating Viscous Surface Wave Propagation Modes in a Finite Depth Fluid
Authors: Arash Ghahraman, Gyula Bene
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The object of this study is to investigate the effect of viscosity on the propagation of free-surface waves in an incompressible viscous fluid layer of arbitrary depth. While we provide a more detailed study of properties of linear surface waves, the description of fully nonlinear waves in terms of KdV-like (Korteweg-de Vries) equations is discussed. In the linear case, we find that in shallow enough fluids, no surface waves can propagate. Even in any thicker fluid layers, propagation of very short and very long waves is forbidden. When wave propagation is possible, only a single propagating mode exists for any given horizontal wave number. The numerical results show that there can be two types of non-propagating modes. One type is always present, and there exist still infinitely many of such modes at the same parameters. In contrast, there can be zero, one or two modes belonging to the other type. Another significant feature is that KdV-like equations. They describe propagating nonlinear viscous surface waves. Since viscosity gives rise to a new wavenumber that cannot be small at the same time as the original one, these equations may not exist. Nonetheless, we propose a reasonable nonlinear description in terms of 1+1 variate functions that make possible successive approximations.Keywords: free surface wave, water waves, KdV equation, viscosity
Procedia PDF Downloads 1451451 Numerical Study of Nonlinear Guided Waves in Composite Laminates with Delaminations
Authors: Reza Soleimanpour, Ching Tai Ng
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Fibre-composites are widely used in various structures due to their attractive properties such as higher stiffness to mass ratio and better corrosion resistance compared to metallic materials. However, one serious weakness of this composite material is delamination, which is a subsurface separation of laminae. A low level of this barely visible damage can cause a significant reduction in residual compressive strength. In the last decade, the application of guided waves for damage detection has been a topic of significant interest for many researches. Among all guided wave techniques, nonlinear guided wave has shown outstanding sensitivity and capability for detecting different types of damages, e.g. cracks and delaminations. So far, most of researches on applications of nonlinear guided wave have been dedicated to isotropic material, such as aluminium and steel, while only a few works have been done on applications of nonlinear characteristics of guided waves in anisotropic materials. This study investigates the nonlinear interactions of the fundamental antisymmetric lamb wave (A0) with delamination in composite laminates using three-dimensional (3D) explicit finite element (FE) simulations. The nonlinearity considered in this study arises from interactions of two interfaces of sub-laminates at the delamination region, which generates contact acoustic nonlinearity (CAN). The aim of this research is to investigate the phenomena of CAN in composite laminated beams by a series of numerical case studies. In this study interaction of fundamental antisymmetric lamb wave with delamination of different sizes are studied in detail. The results show that the A0 lamb wave interacts with the delaminations generating CAN in the form of higher harmonics, which is a good indicator for determining the existence of delaminations in composite laminates.Keywords: contact acoustic nonlinearity, delamination, fibre reinforced composite beam, finite element, nonlinear guided waves
Procedia PDF Downloads 2001450 Boundary Conditions for 2D Site Response Analysis in OpenSees
Authors: M. Eskandarighadi, C. R. McGann
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It is observed from past experiences of earthquakes that local site conditions can significantly affect the strong ground motion characteristicssuch as frequency content, amplitude, and duration of seismic waves. The most common method for investigating site response is one-dimensional seismic site response analysis. The infinite horizontal length of the model and the homogeneous characteristic of the soil are crucial assumptions of this method. One boundary condition that can be used in the sides is tying the sides horizontally for vertical 1D wave propagation. However, 1D analysis cannot account for the 2D nature of wave propagation in the condition where the soil profile is not fully horizontal or has heterogeneity within layers. Therefore, 2D seismic site response analysis can be used to take all of these limitations into account for a better understanding of local site conditions. Different types of boundary conditions can be appliedin 2D site response models, such as tied boundary condition, massive columns, and free-field boundary condition. The tied boundary condition has been used in 1D analysis, which is useful for 1D wave propagation. Employing two massive columns at the sides is another approach for capturing the 2D nature of wave propagation. Free-field boundary condition can simulate the free-field motion that would exist far from the domain of interest. The goal for free-field boundary condition is to minimize the unwanted reflection from sides. This research focuses on the comparison between these methods with examples and discusses the details and limitations of each of these boundary conditions.Keywords: boundary condition, free-field, massive columns, opensees, site response analysis, wave propagation
Procedia PDF Downloads 1661449 Estimation of Shear Wave Velocity from Cone Penetration Test for Structured Busan Clays
Authors: Vinod K. Singh, S. G. Chung
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The degree of structuration of Busan clays at the mouth of Nakdong River mouth was highly influenced by the depositional environment, i.e., flow of the river stream, marine regression, and transgression during the sedimentation process. As a result, the geotechnical properties also varies along the depth with change in degree of structuration. Thus, the in-situ tests such as cone penetration test (CPT) could not be used to predict various geotechnical properties properly by using the conventional empirical methods. In this paper, the shear wave velocity (Vs) was measured from the field using the seismic dilatometer. The Vs was also measured in the laboratory from high quality undisturbed and remolded samples using bender element method to evaluate the degree of structuration. The degree of structuration was quantitatively defined by the modulus ratio of undisturbed to remolded soil samples which is found well correlated with the normalized void ratio (e0/eL) where eL is the void ratio at the liquid limit. It is revealed that the empirical method based on laboratory results incorporating e0/eL can predict Vs from the field more accurately. Thereafter, the CPT based empirical method was developed to estimate the shear wave velocity taking the effect of structuration in the consideration. The developed method was found to predict shear wave velocity reasonably for Busan clays.Keywords: level of structuration, normalized modulus, normalized void ratio, shear wave velocity, site characterization
Procedia PDF Downloads 2301448 Numerical Investigation of the Effect of Blast Pressure on Discrete Model in Shock Tube
Authors: Aldin Justin Sundararaj, Austin Lord Tennyson, Divya Jose, A. N. Subash
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Blast waves are generated due to the explosions of high energy materials. An explosion yielding a blast wave has the potential to cause severe damage to buildings and its personnel. In order to understand the physics of effects of blast pressure on buildings, studies in the shock tube on generic configurations are carried out at various pressures on discrete models. The strength of shock wave is systematically varied by using different driver gases and diaphragm thickness. The basic material of the diaphragm is Aluminum. To simulate the effect of shock waves on discrete models a shock tube was used. Generic models selected for this study are suitably scaled cylinder, cone and cubical blocks. The experiments were carried out with 2mm diaphragm with burst pressure ranging from 28 to 31 bar. Numerical analysis was carried out over these discrete models. A 3D model of shock-tube with different discrete models inside the tube was used for CFD computation. It was found that cone has dissipated most of the shock pressure compared to cylinder and cubical block. The robustness and the accuracy of the numerical model were validation with the analytical and experimental data.Keywords: shock wave, blast wave, discrete models, shock tube
Procedia PDF Downloads 322