Search results for: generalized beam theory
3346 Rare-Earth Ions Doped Lithium Niobate Crystals: Luminescence and Raman Spectroscopy
Authors: Ninel Kokanyan, Edvard Kokanyan, Anush Movsesyan, Marc D. Fontana
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Lithium Niobate (LN) is one of the widely used ferroelectrics having a wide number of applications such as phase-conjugation, holographic storage, frequency doubling, SAW sensors. Furthermore, the possibility of doping with rare-earth ions leads to new laser applications. Ho and Tm dopants seem interesting due to laser emission obtained at around 2 µm. Raman spectroscopy is a powerful spectroscopic technique providing a possibility to obtain a number of information about physicochemical and also optical properties of a given material. Polarized Raman measurements were carried out on Ho and Tm doped LN crystals with excitation wavelengths of 532nm and 785nm. In obtained Raman anti-Stokes spectra, we detect expected modes according to Raman selection rules. In contrast, Raman Stokes spectra are significantly different compared to what is expected by selection rules. Additional forbidden lines are detected. These lines have quite high intensity and are well defined. Moreover, the intensity of mentioned additional lines increases with an increase of Ho or Tm concentrations in the crystal. These additional lines are attributed to emission lines reflecting the photoluminescence spectra of these crystals. It means that in our case we were able to detect, within a very good resolution, in the same Stokes spectrum, the transitions between the electronic states, and the vibrational states as well. The analysis of these data is reported as a function of Ho and Tm content, for different polarizations and wavelengths, of the incident laser beam. Results also highlight additional information about π and σ polarizations of crystals under study.Keywords: lithium niobate, Raman spectroscopy, luminescence, rare-earth ions doped lithium niobate
Procedia PDF Downloads 2233345 Hydraulic Characteristics of Mine Tailings by Metaheuristics Approach
Authors: Akhila Vasudev, Himanshu Kaushik, Tadikonda Venkata Bharat
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A large number of mine tailings are produced every year as part of the extraction process of phosphates, gold, copper, and other materials. Mine tailings are high in water content and have very slow dewatering behavior. The efficient design of tailings dam and economical disposal of these slurries requires the knowledge of tailings consolidation behavior. The large-strain consolidation theory closely predicts the self-weight consolidation of these slurries as the theory considers the conservation of mass and momentum conservation and considers the hydraulic conductivity as a function of void ratio. Classical laboratory techniques, such as settling column test, seepage consolidation test, etc., are expensive and time-consuming for the estimation of hydraulic conductivity variation with void ratio. Inverse estimation of the constitutive relationships from the measured settlement versus time curves is explored. In this work, inverse analysis based on metaheuristics techniques will be explored for predicting the hydraulic conductivity parameters for mine tailings from the base excess pore water pressure dissipation curve and the initial conditions of the mine tailings. The proposed inverse model uses particle swarm optimization (PSO) algorithm, which is based on the social behavior of animals searching for food sources. The finite-difference numerical solution of the forward analytical model is integrated with the PSO algorithm to solve the inverse problem. The method is tested on synthetic data of base excess pore pressure dissipation curves generated using the finite difference method. The effectiveness of the method is verified using base excess pore pressure dissipation curve obtained from a settling column experiment and further ensured through comparison with available predicted hydraulic conductivity parameters.Keywords: base excess pore pressure, hydraulic conductivity, large strain consolidation, mine tailings
Procedia PDF Downloads 1383344 [Keynote Talk]: Let Us Move to Ethical Finance: A Case Study of Takaful
Authors: Syed Ahmed Salman
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Ethicality is essential in our daily activities, including personal and commercial activities. This is evidenced by referring to the historical development of the corporate governance and ethical guidelines. The first corporate governance guideline, i.e. Cadbury Report from U.K. focuses the responsibility of board members towards the shareholders only. Gradually, realising the need to take care of the society and community, stakeholders are now concerns of business entities. Consequently, later codes of corporate governance started extending the responsibility to the other stakeholders in addition to the shareholders. One prevailing corporate governance theory, i.e. stakeholder theory, has been widely used in the research to explore the effects of business entities on society. In addition, the Global Reporting Initiative (GRI) is the leading organisation which promotes social care from businesses for sustainable development. Conventionally, history shows that ethics is key to the long term success of businesses. Many organisations, societies, and regulators give full attention and consideration to ethics. Several countries have introduced ethical codes of conduct to direct trade activities. Similarly, Islam and other religions prohibit the practice of interest, uncertainty, and gambling because of its unethical nature. These prohibited practices are not at all good for the society, business, and any organisation especially as it is detrimental to the well-being of society. In order to avoid unethicality in the finance industry, Shari’ah scholars come out with the idea of Islamic finance which is free from the prohibited elements from the Islamic perspective. It can also be termed ethical finance. This paper highlights how Takaful as one of the Islamic finance products offers fair and just products to the contracting parties and the society. Takaful is framed based on ethical guidelines which are extracted from Shari’ah principles and divine sources such as the Quran and Sunnah. Takaful products have been widely offered all over the world, including in both Muslim and non-Muslim countries. It seems that it is gaining acceptance regardless of religion. This is evidence that Takaful is being accepted as an ethical financial product.Keywords: ethics, insurance, Islamic finance, religion and takaful
Procedia PDF Downloads 2743343 On the Solidness of the Polar of Recession Cones
Authors: Sima Hassankhali, Ildar Sadeqi
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In the theory of Pareto efficient points, the existence of a bounded base for a cone K of a normed space X is so important. In this article, we study the geometric structure of a nonzero closed convex cone K with a bounded base. For this aim, we study the structure of the polar cone K# of K. Furthermore, we obtain a necessary and sufficient condition for a nonempty closed convex set C so that its recession cone C∞ has a bounded base.Keywords: solid cones, recession cones, polar cones, bounded base
Procedia PDF Downloads 2683342 An Iberian Study about Location of Parking Areas for Dangerous Goods
Authors: María Dolores Caro, Eugenio M. Fedriani, Ángel F. Tenorio
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When lorries transport dangerous goods, there exist some legal stipulations in the European Union for assuring the security of the rest of road users as well as of those goods being transported. At this respect, lorry drivers cannot park in usual parking areas, because they must use parking areas with special conditions, including permanent supervision of security personnel. Moreover, drivers are compelled to satisfy additional regulations about resting and driving times, which involve in the practical possibility of reaching the suitable parking areas under these time parameters. The “European Agreement concerning the International Carriage of Dangerous Goods by Road” (ADR) is the basic regulation on transportation of dangerous goods imposed under the recommendations of the United Nations Economic Commission for Europe. Indeed, nowadays there are no enough parking areas adapted for dangerous goods and no complete study have suggested the best locations to build new areas or to adapt others already existing to provide the areas being necessary so that lorry drivers can follow all the regulations. The goal of this paper is to show how many additional parking areas should be built in the Iberian Peninsula to allow that lorry drivers may park in such areas under their restrictions in resting and driving time. To do so, we have modeled the problem via graph theory and we have applied a new efficient algorithm which determines an optimal solution for the problem of locating new parking areas to complement those already existing in the ADR for the Iberian Peninsula. The solution can be considered minimal since the number of additional parking areas returned by the algorithm is minimal in quantity. Obviously, graph theory is a natural way to model and solve the problem here proposed because we have considered as nodes: the already-existing parking areas, the loading-and-unloading locations and the bifurcations of roads; while each edge between two nodes represents the existence of a road between both nodes (the distance between nodes is the edge's weight). Except for bifurcations, all the nodes correspond to parking areas already existing and, hence, the problem corresponds to determining the additional nodes in the graph such that there are less up to 100 km between two nodes representing parking areas. (maximal distance allowed by the European regulations).Keywords: dangerous goods, parking areas, Iberian peninsula, graph-based modeling
Procedia PDF Downloads 5833341 The Moderating Role of Payment Platform Applications’ Relationship with Increasing Purchase Intention Among Customers in Kuwait - Unified Theory of Acceptance and Sustainable Use of Technology Model
Authors: Ahmad Alsaber
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This paper aims to understand the intermediary role of the payment platform applications by analyzing the various factors that can influence the desirability of utilizing said payment services in Kuwait, as well as to determine the effect of the presence of different types of payment platforms on the variables of the “Unified Theory of Acceptance and Use of Technology” (UTAUT) model. The UTAUT model's findings will provide an important understanding of the moderating role of payment platform mobile applications. This study will explore the influence of payment platform mobile applications on customer purchase intentions in Kuwait by employing a quantitative survey of 200 local customers. Questions will cover their usage of payment platforms, purchase intent, and overall satisfaction. The information gathered is then analyzed using descriptive statistics and correlation analysis in order to gain insights. The research hopes to provide greater insight into the effect of mobile payment platforms on customer purchase intentions in Kuwait. This research will provide important implications to marketers and customer service providers, informing their strategies and initiatives, as well as offer recommendations to payment platform providers on how to improve customer satisfaction and security. The study results suggest that the likelihood of a purchase is affected by performance expectancy, effort expectancy, social influence, risk, and trust. The purpose of this research is to understand the advancements in the different variables that Kuwaiti customers consider while dealing with mobile banking applications. With the implementation of stronger security measures, progressively more payment platform applications are being utilized in the Kuwaiti marketplace, making them more desirable with their accessibility and usability. With the development of the Kuwaiti digital economy, it is expected that mobile banking will have a greater impact on banking transactions and services in the future.Keywords: purchase intention, UTAUT, performance expectancy, social influence, risk, trust
Procedia PDF Downloads 1223340 The Novelty of Mobile Money Solution to Ghana’S Cashless Future: Opportunities, Challenges and Way Forward
Authors: Julius Y Asamoah
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Mobile money has seen faster adoption in the decade. Its emergence serves as an essential driver of financial inclusion and an innovative financial service delivery channel, especially to the unbanked population. The rising importance of mobile money services has caught policymakers and regulators' attention, seeking to understand the many issues emerging from this context. At the same time, it is unlocking the potential of knowledge of this new technology. Regulatory responses and support are essential, requiring significant changes to current regulatory practices in Ghana. The article aims to answer the following research questions: "What risk does an unregulated mobile money service pose to consumers and the financial system? "What factors stimulate and hinder the introduction of mobile payments in developing countries? The sample size used was 250 respondents selected from the study area. The study has adopted an analytical approach comprising a combination of qualitative and quantitative data collection methods. Actor-network theory (ANT) is used as an interpretive lens to analyse this process. ANT helps analyse how actors form alliances and enrol other actors, including non-human actors (i.e. technology), to secure their interests. The study revealed that government regulatory policies impact mobile money as critical to mobile money services in developing countries. Regulatory environment should balance the needs of advancing access to finance with the financial system's stability and draw extensively from Kenya's work as the best strategies for the system's players. Thus, regulators need to address issues related to the enhancement of supportive regulatory frameworks. It recommended that the government involve various stakeholders, such as mobile phone operators. Moreover, the national regulatory authority creates a regulatory environment that promotes fair practices and competition to raise revenues to support a business-enabling environment's key pillars as infrastructure.Keywords: actor-network theory (ANT), cashless future, Developing countries, Ghana, Mobile Money
Procedia PDF Downloads 1393339 Curve Designing Using an Approximating 4-Point C^2 Ternary Non-Stationary Subdivision Scheme
Authors: Muhammad Younis
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A ternary 4-point approximating non-stationary subdivision scheme has been introduced that generates the family of $C^2$ limiting curves. The theory of asymptotic equivalence is being used to analyze the convergence and smoothness of the scheme. The comparison of the proposed scheme has been demonstrated using different examples with the existing 4-point ternary approximating schemes, which shows that the limit curves of the proposed scheme behave more pleasantly and can generate conic sections as well.Keywords: ternary, non-stationary, approximation subdivision scheme, convergence and smoothness
Procedia PDF Downloads 4783338 Rule-Of-Mixtures: Predicting the Bending Modulus of Unidirectional Fiber Reinforced Dental Composites
Authors: Niloofar Bahramian, Mohammad Atai, Mohammad Reza Naimi-Jamal
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Rule of mixtures is the simple analytical model is used to predict various properties of composites before design. The aim of this study was to demonstrate the benefits and limitations of the Rule-of-Mixtures (ROM) for predicting bending modulus of a continuous and unidirectional fiber reinforced composites using in dental applications. The Composites were fabricated from light curing resin (with and without silica nanoparticles) and modified and non-modified fibers. Composite samples were divided into eight groups with ten specimens for each group. The bending modulus (flexural modulus) of samples was determined from the slope of the initial linear region of stress-strain curve on 2mm×2mm×25mm specimens with different designs: fibers corona treatment time (0s, 5s, 7s), fibers silane treatment (0%wt, 2%wt), fibers volume fraction (41%, 33%, 25%) and nanoparticles incorporation in resin (0%wt, 10%wt, 15%wt). To study the fiber and matrix interface after fracture, single edge notch beam (SENB) method and scanning electron microscope (SEM) were used. SEM also was used to show the nanoparticles dispersion in resin. Experimental results of bending modulus for composites made of both physical (corona) and chemical (silane) treated fibers were in reasonable agreement with linear ROM estimates, but untreated fibers or non-optimized treated fibers and poor nanoparticles dispersion did not correlate as well with ROM results. This study shows that the ROM is useful to predict the mechanical behavior of unidirectional dental composites but fiber-resin interface and quality of nanoparticles dispersion play important role in ROM accurate predictions.Keywords: bending modulus, fiber reinforced composite, fiber treatment, rule-of-mixtures
Procedia PDF Downloads 2773337 Count Regression Modelling on Number of Migrants in Households
Authors: Tsedeke Lambore Gemecho, Ayele Taye Goshu
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The main objective of this study is to identify the determinants of the number of international migrants in a household and to compare regression models for count response. This study is done by collecting data from total of 2288 household heads of 16 randomly sampled districts in Hadiya and Kembata-Tembaro zones of Southern Ethiopia. The Poisson mixed models, as special cases of the generalized linear mixed model, is explored to determine effects of the predictors: age of household head, farm land size, and household size. Two ethnicities Hadiya and Kembata are included in the final model as dummy variables. Stepwise variable selection has indentified four predictors: age of head, farm land size, family size and dummy variable ethnic2 (0=other, 1=Kembata). These predictors are significant at 5% significance level with count response number of migrant. The Poisson mixed model consisting of the four predictors with random effects districts. Area specific random effects are significant with the variance of about 0.5105 and standard deviation of 0.7145. The results show that the number of migrant increases with heads age, family size, and farm land size. In conclusion, there is a significantly high number of international migration per household in the area. Age of household head, family size, and farm land size are determinants that increase the number of international migrant in households. Community-based intervention is needed so as to monitor and regulate the international migration for the benefits of the society.Keywords: Poisson regression, GLM, number of migrant, Hadiya and Kembata Tembaro zones
Procedia PDF Downloads 2853336 Electro Spinning in Nanotechnology
Authors: Mahoud Alfama, Meloud Yones, Abdelbaset Zroga, Abdelati Elalem
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Electrospinning has been recognized as an efficient technique for the fabrication of polymer nanofibers. Various polymers have been successfully electrospun into ultrafine fibers in recent years mostly in solvent solution and some in melt form. Potential applications based on such fibers specifically their use as reinforcement in nanocomposite development have been realized. In this paper we examine -electrospinning by providing a brief description of the theory behind the process examining the effect of changing the process parameters on fiber morphology, and discussing the potential applications and impacts of electrospinning on the field of tissue engineering.Keywords: nanotechnology, electro spinning, reinforced materials
Procedia PDF Downloads 2923335 Driving What’s Next: The De La Salle Lipa Social Innovation in Quality Education Initiatives
Authors: Dante Jose R. Amisola, Glenford M. Prospero
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'Driving What’s Next' is a strong campaign of the new administration of De La Salle Lipa in promoting social innovation in quality education. The new leadership directs social innovation in quality education in the institutional directions and initiatives to address real-world challenges with real-world solutions. This research under study aims to qualify the commitment of the institution to extend the Lasallian quality human and Christian education to all, as expressed in the Institution’s new mission-vision statement. The Classic Grounded Theory methodology is employed in the process of generating concepts in reference to the documents, a series of meetings, focus group discussions and other related activities that account for the conceptualization and formulation of the new mission-vision along with the new education innovation framework. Notably, Driving What’s Next is the emergent theory that encapsulates the commitment of giving quality human and Christian education to all. It directs the new leadership in driving social innovation in quality education initiatives. Correspondingly, Driving What’s Next is continually resolved through four interrelated strategies also termed as the institution's four strategic directions, namely: (1) driving social innovation in quality education, (2) embracing our shared humanity and championing social inclusion and justice initiatives, (3) creating sustainable futures and (4) engaging diverse stakeholders in our shared mission. Significantly, the four strategic directions capture and integrate the 17 UN sustainable development goals, making the innovative curriculum locally and globally relevant. To conclude, the main concern of the new administration and how it is continually resolved, provide meaningful and fun learning experiences and promote a new way of learning in the light of the 21st century skills among the members of the academic community including stakeholders and extended communities at large, which are defined as: learning together and by association (collaboration), learning through engagement (communication), learning by design (creativity) and learning with social impact (critical thinking).Keywords: DLSL four strategic directions , DLSL Lipa mission-vision, driving what's next, social innovation in quality education
Procedia PDF Downloads 2183334 Existence Result of Third Order Functional Random Integro-Differential Inclusion
Authors: D. S. Palimkar
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The FRIGDI (functional random integrodifferential inclusion) seems to be new and includes several known random differential inclusions already studied in the literature as special cases have been discussed in the literature for various aspects of the solutions. In this paper, we prove the existence result for FIGDI under the non-convex case of multi-valued function involved in it.Using random fixed point theorem of B. C. Dhage and caratheodory condition. This result is new to the theory of differential inclusion.Keywords: caratheodory condition, random differential inclusion, random solution, integro-differential inclusion
Procedia PDF Downloads 4683333 Teachers’ Protective Factors of Resilience Scale: Factorial Structure, Validity and Reliability Issues
Authors: Athena Daniilidou, Maria Platsidou
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Recently developed scales addressed -specifically- teachers’ resilience. Although they profited from the field, they do not include some of the critical protective factors of teachers’ resilience identified in the literature. To address this limitation, we aimed at designing a more comprehensive scale for measuring teachers' resilience which encompasses various personal and environmental protective factors. To this end, two studies were carried out. In Study 1, 407 primary school teachers were tested with the new scale, the Teachers’ Protective Factors of Resilience Scale (TPFRS). Similar scales, such as the Multidimensional Teachers’ Resilience Scale and the Teachers’ Resilience Scale), were used to test the convergent validity, while the Maslach Burnout Inventory and the Teachers’ Sense of Efficacy Scale was used to assess the discriminant validity of the new scale. The factorial structure of the TPFRS was checked with confirmatory factor analysis and a good fit of the model to the data was found. Next, item response theory analysis using a two-parameter model (2PL) was applied to check the items within each factor. It revealed that 9 items did not fit the corresponding factors well and they were removed. The final version of the TPFRS includes 29 items, which assess six protective factors of teachers’ resilience: values and beliefs (5 items, α=.88), emotional and behavioral adequacy (6 items, α=.74), physical well-being (3 items, α=.68), relationships within the school environment, (6 items, α=.73) relationships outside the school environment (5 items, α=.84), and the legislative framework of education (4 items, α=.83). Results show that it presents a satisfactory convergent and discriminant validity. Study 2, in which 964 primary and secondary school teachers were tested, confirmed the factorial structure of the TPFRS as well as its discriminant validity, which was tested with the Schutte Emotional Intelligence Scale-Short Form. In conclusion, our results confirmed that the TPFRS is a valid instrument for assessing teachers' protective factors of resilience and it can be safely used in future research and interventions in the teaching profession. In conclusion, our results showed that the TPFRS is a new multi-dimensional instrument valid for assessing teachers' protective factors of resilience and it can be safely used in future research and interventions in the teaching profession.Keywords: resilience, protective factors, teachers, item response theory
Procedia PDF Downloads 1033332 Understanding the Impact of Background Experience from Staff in Diversion Programs: The Voices of a Community-Based Diversion Program
Authors: Ana Magana
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Youth are entering the juvenile justice system at alarming rates. For the youth of color entering the system, the outcomes are far worse than for their white counterparts. In fact, the youth of color are more likely to be arrested and sentenced for longer periods of time than white youth. Race disproportionality in the juvenile justice system is evident, but what happens to the youth that exit the juvenile justice system? Who supports them after they are incarcerated and who can prevent them from re-offending? There are several diversion programs that have been implemented in the US to aid the reduction of juvenile incarceration and help reduce recidivism. The program interviewed for this study is a community-based diversion program (CBDP). The CBDP is a pre-filing diversion non-profit organization based in South Seattle. The objective of this exploratory research study is to provide a space and platform for the CBDP team to speak about their background experiences and the influence their background has on their current approach and practice with juveniles. A qualitative, exploratory study was conducted. Interviews were conducted with staff and provided oral consent. The interview included six open-ended, semi-structured questions. Interviews were digitally recoded and transcribed. The aim of this study was to understand how the influence of the participant’s backgrounds and previous experiences impact their current practice approaches with the CBDP youth and young adults. Ecological systems theory was the guiding framework for analysis. After careful analysis, three major themes emerged: 1) strong influence of participant’s background, 2) participants belonging to community and 3) strong self-identity with the CBDP. Within these three themes, subthemes were developed based on participant’s responses. It was concluded that the participant’s approach is influenced by their background experiences. This corresponds to the ecological systems theory and the community-based lens which underscores theoretical analysis. The participant’s approach is grounded in interpersonal relationships within the client’s systems, meaning that the participants understand and view their clients within an ecological systems perspective. When choosing participants that reflect the population being served, the clients receive a balanced, inclusive and caring approach. Youth and young adults are searching for supportive adults to be there for them, it is essential for diversion programs to provide a space for shared background experiences and have people that hold similar identities. Grassroots organizations such as CBDP have the tools and experience to work with marginalized populations that are constantly being passed on. While articles and studies focus on the reduction of recidivism and re-offending it is important to question the reasons behind this data. For instance, there can be a reduction in statistics, but at whose expense. Are the youth and young adults truly being supported? Or is it just a requirement that they are completing in order to remove their charge? This research study can serve as the beginning of a series of studies conducted at CBDP to further understand and validate the need to employ individuals with similar backgrounds as the participants CBDP serves.Keywords: background experience, diversion, ecological systems theory, relationships
Procedia PDF Downloads 1463331 Numerical Study of Flapping-Wing Flight of Hummingbird Hawkmoth during Hovering: Longitudinal Dynamics
Authors: Yao Jie, Yeo Khoon Seng
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In recent decades, flapping wing aerodynamics has attracted great interest. Understanding the physics of biological flyers such as birds and insects can help improve the performance of micro air vehicles. The present research focuses on the aerodynamics of insect-like flapping wing flight with the approach of numerical computation. Insect model of hawkmoth is adopted in the numerical study with rigid wing assumption currently. The numerical model integrates the computational fluid dynamics of the flow and active control of wing kinematics to achieve stable flight. The computation grid is a hybrid consisting of background Cartesian nodes and clouds of mesh-free grids around immersed boundaries. The generalized finite difference method is used in conjunction with single value decomposition (SVD-GFD) in computational fluid dynamics solver to study the dynamics of a free hovering hummingbird hawkmoth. The longitudinal dynamics of the hovering flight is governed by three control parameters, i.e., wing plane angle, mean positional angle and wing beating frequency. In present work, a PID controller works out the appropriate control parameters with the insect motion as input. The controller is adjusted to acquire desired maneuvering of the insect flight. The numerical scheme in present study is proven to be accurate and stable to simulate the flight of the hummingbird hawkmoth, which has relatively high Reynolds number. The PID controller is responsive to provide feedback to the wing kinematics during the hovering flight. The simulated hovering flight agrees well with the real insect flight. The present numerical study offers a promising route to investigate the free flight aerodynamics of insects, which could overcome some of the limitations of experiments.Keywords: aerodynamics, flight control, computational fluid dynamics (CFD), flapping-wing flight
Procedia PDF Downloads 3513330 A Test to Express Diagnostic Cohesion of Football Team
Authors: Alexandra O. Savinkina
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We proposed to assess the cohesion of a football team by its subject-goal and subject-value unity according to the A.V. Petrovsky theory. Goal unity was measured by the degree of compliance of the priority targets for various players in the team. Values were estimated by the coincidence of the ideas about a perfect football player. On the basis of the provisional diagnosis of the six teams, we had made the lists of goals and values. The tests were piloted on 35 football teams. The results allowed not only to compare quantitatively the cohesion of the different teams, but also to identify subgroups within the team.Keywords: cohesion, football, psychodiagnostic, soccer, sports team, value-orientation unity
Procedia PDF Downloads 2853329 Digital Image Correlation Based Mechanical Response Characterization of Thin-Walled Composite Cylindrical Shells
Authors: Sthanu Mahadev, Wen Chan, Melanie Lim
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Anisotropy dominated continuous-fiber composite materials have garnered attention in numerous mechanical and aerospace structural applications. Tailored mechanical properties in advanced composites can exhibit superiority in terms of stiffness-to-weight ratio, strength-to-weight ratio, low-density characteristics, coupled with significant improvements in fatigue resistance as opposed to metal structure counterparts. Extensive research has demonstrated their core potential as more than just mere lightweight substitutes to conventional materials. Prior work done by Mahadev and Chan focused on formulating a modified composite shell theory based prognosis methodology for investigating the structural response of thin-walled circular cylindrical shell type composite configurations under in-plane mechanical loads respectively. The prime motivation to develop this theory stemmed from its capability to generate simple yet accurate closed-form analytical results that can efficiently characterize circular composite shell construction. It showcased the development of a novel mathematical framework to analytically identify the location of the centroid for thin-walled, open cross-section, curved composite shells that were characterized by circumferential arc angle, thickness-to-mean radius ratio, and total laminate thickness. Ply stress variations for curved cylindrical shells were analytically examined under the application of centric tensile and bending loading. This work presents a cost-effective, small-platform experimental methodology by taking advantage of the full-field measurement capability of digital image correlation (DIC) for an accurate assessment of key mechanical parameters such as in-plane mechanical stresses and strains, centroid location etc. Mechanical property measurement of advanced composite materials can become challenging due to their anisotropy and complex failure mechanisms. Full-field displacement measurements are well suited for characterizing the mechanical properties of composite materials because of the complexity of their deformation. This work encompasses the fabrication of a set of curved cylindrical shell coupons, the design and development of a novel test-fixture design and an innovative experimental methodology that demonstrates the capability to very accurately predict the location of centroid in such curved composite cylindrical strips via employing a DIC based strain measurement technique. Error percentage difference between experimental centroid measurements and previously estimated analytical centroid results are observed to be in good agreement. The developed analytical modified-shell theory provides the capability to understand the fundamental behavior of thin-walled cylindrical shells and offers the potential to generate novel avenues to understand the physics of such structures at a laminate level.Keywords: anisotropy, composites, curved cylindrical shells, digital image correlation
Procedia PDF Downloads 3183328 A Study on the Use Intention of Smart Phone
Authors: Zhi-Zhong Chen, Jun-Hao Lu, Jr., Shih-Ying Chueh
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Based on Unified Theory of Acceptance and Use of Technology (UTAUT), the study investigates people’s intention on using smart phones. The study additionally incorporates two new variables: 'self-efficacy' and 'attitude toward using'. Samples are collected by questionnaire survey, in which 240 are valid. After Correlation Analysis, Reliability Test, ANOVA, t-test and Multiple Regression Analysis, the study finds that social impact and self-efficacy have positive effect on use intentions, and the use intentions also have positive effect on use behavior.Keywords: [1] Ajzen & Fishbein (1975), “Belief, attitude, intention and behavior: An introduction to theory and research”, Reading MA: Addison-Wesley. [2] Bandura (1977) Self-efficacy: toward a unifying theory of behavioural change. Psychological Review , 84, 191–215. [3] Bandura( 1986) A. Bandura, Social foundations of though and action, Prentice-Hall. Englewood Cliffs. [4] Ching-Hui Huang (2005). The effect of Regular Exercise on Elderly Optimism: The Self-efficacy and Theory of Reasoned Action Perspectives.(Master's dissertation, National Taiwan Sport University, 2005).National Digital Library of Theses and Dissertations in Taiwan。 [5] Chun-Mo Wu (2007).The Effects of Perceived Risk and Service Quality on Purchase Intention - an Example of Taipei City Long-Term Care Facilities. (Master's dissertation, Ming Chuan University, 2007).National Digital Library of Theses and Dissertations in Taiwan. [6] Compeau, D.R., and Higgins, C.A., (1995) “Application of social cognitive theory to training for computer skills.”, Information Systems Research, 6(2), pp.118-143. [7] computer-self-efficacy and mediators of the efficacy-performance relationship. International Journal of Human-Computer Studies, 62, 737-758. [8] Davis et al(1989), “User acceptance of computer technology: A comparison of two theoretical models ”, Management Science, 35(8), p.982-1003. [9] Davis et al(1989), “User acceptance of computer technology:A comparison of two theoretical models ”, Management Science, 35(8), p.982-1003. [10] Davis, F.D. (1989). Perceived Usefulness, Perceived Ease of Use and User Acceptance of Information Technology. MIS Quarterly, 13(3), 319-340。 [11] Davis. (1989). Perceived Usefulness, Perceived Ease of Use, and User Acceptance of Information Technology. MIS Quarterly, 13(3), 319–340. doi:10.2307/249008 [12] Johnson, R. D. (2005). An empirical investigation of sources of application-specific [13] Mei-yin Hsu (2010).The Study on Attitude and Satisfaction of Electronic Documents System for Administrators of Elementary Schools in Changhua County.(Master's dissertation , Feng Chia University, 2010).National Digital Library of Theses and Dissertations in Taiwan. [14] Ming-Chun Hsieh (2010). Research on Parents’ Attitudes Toward Electronic Toys: The case of Taichung City.(Master's dissertation, Chaoyang University of Technology,2010).National Digital Library of Theses and Dissertations in Taiwan. [15] Moon and Kim(2001). Extending the TAM for a World-Wide-Web context, Information and Management, v.38 n.4, p.217-230. [16] Shang-Yi Hu (2010).The Impacts of Knowledge Management on Customer Relationship Management – Enterprise Characteristicsand Corporate Governance as a Moderator.(Master's dissertation, Leader University, 2010)。National Digital Library of Theses and Dissertations in Taiwan. [17] Sheng-Yi Hung (2013, September10).Worldwide sale of smartphones to hit one billion IDC:Android dominate the market. ETtoday. Retrieved data form the available protocol:2013/10/3. [18] Thompson, R.L., Higgins, C.A., and Howell, J.M.(1991), “Personal Computing: Toward a Conceptual Model of Utilization”, MIS Quarterly(15:1), pp. 125-143. [19] Venkatesh, V., M.G. Morris, G.B. Davis, and F. D. Davis (2003), “User acceptance of information technology: Toward a unified view, ” MIS Quarterly, 27, No. 3, pp.425-478. [20] Vijayasarathy, L. R. (2004), Predicting Consumer Intentions to Use On-Line Shopping: The Case for an Augmented Technology Acceptance Model, Information and Management, Vol.41, No.6, pp.747-762. [21] Wikipedia - smartphone (http://zh.wikipedia.org/zh-tw/%E6%99%BA%E8%83%BD%E6%89%8B%E6%9C%BA)。 [22] Wu-Minsan (2008).The impacts of self-efficacy, social support on work adjustment with hearing impaired. (Master's dissertation, Southern Taiwan University of Science and Technology, 2008).National Digital Library of Theses and Dissertations in Taiwan. [23] Yu-min Lin (2006). The Influence of Business Employee’s MSN Self-efficacy On Instant Messaging Usage Behavior and Communicaiton Satisfaction.(Master's dissertation, National Taiwan University of Science and Technology, 2006).National Digital Library of Theses and Dissertations in Taiwan.
Procedia PDF Downloads 4113327 Electromagnetic Tuned Mass Damper Approach for Regenerative Suspension
Authors: S. Kopylov, C. Z. Bo
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This study is aimed at exploring the possibility of energy recovery through the suppression of vibrations. The article describes design of electromagnetic dynamic damper. The magnetic part of the device performs the function of a tuned mass damper, thereby providing both energy regeneration and damping properties to the protected mass. According to the theory of tuned mass damper, equations of mathematical models were obtained. Then, under given properties of current system, amplitude frequency response was investigated. Therefore, main ideas and methods for further research were defined.Keywords: electromagnetic damper, oscillations with two degrees of freedom, regeneration systems, tuned mass damper
Procedia PDF Downloads 2123326 Automatic Vowel and Consonant's Target Formant Frequency Detection
Authors: Othmane Bouferroum, Malika Boudraa
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In this study, a dual exponential model for CV formant transition is derived from locus theory of speech perception. Then, an algorithm for automatic vowel and consonant’s target formant frequency detection is developed and tested on real speech. The results show that vowels and consonants are detected through transitions rather than their small stable portions. Also, vowel reduction is clearly observed in our data. These results are confirmed by the observations made in perceptual experiments in the literature.Keywords: acoustic invariance, coarticulation, formant transition, locus equation
Procedia PDF Downloads 2743325 Becoming Vegan: The Theory of Planned Behavior and the Moderating Effect of Gender
Authors: Estela Díaz
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This article aims to make three contributions. First, build on the literature on ethical decision-making literature by exploring factors that influence the intention of adopting veganism. Second, study the superiority of extended models of the Theory of Planned Behavior (TPB) for understanding the process involved in forming the intention of adopting veganism. Third, analyze the moderating effect of gender on TPB given that attitudes and behavior towards animals are gender-sensitive. No study, to our knowledge, has examined these questions. Veganism is not a diet but a political and moral stand that exclude, for moral reasons, the use of animals. Although there is a growing interest in studying veganism, it continues being overlooked in empirical research, especially within the domain of social psychology. TPB has been widely used to study a broad range of human behaviors, including moral issues. Nonetheless, TPB has rarely been applied to examine ethical decisions about animals and, even less, to veganism. Hence, the validity of TPB in predicting the intention of adopting veganism remains unanswered. A total of 476 non-vegan Spanish university students (55.6% female; the mean age was 23.26 years, SD= 6.1) responded to online and pencil-and-paper self-reported questionnaire based on previous studies. TPB extended models incorporated two background factors: ‘general attitudes towards humanlike-attributes ascribed to animals’ (AHA) (capacity for reason/emotions/suffer, moral consideration, and affect-towards-animals); and ‘general attitudes towards 11 uses of animals’ (AUA). SPSS 22 and SmartPLS 3.0 were used for statistical analyses. This study constructed a second-order reflective-formative model and took the multi-group analysis (MGA) approach to study gender effects. Six models of TPB (the standard and five competing) were tested. No a priori hypotheses were formulated. The results gave partial support to TPB. Attitudes (ATTV) (β = .207, p < .001), subjective norms (SNV) (β = .323, p < .001), and perceived control behavior (PCB) (β = .149, p < .001) had a significant direct effect on intentions (INTV). This model accounted for 27,9% of the variance in intention (R2Adj = .275) and had a small predictive relevance (Q2 = .261). However, findings from this study reveal that contrary to what TPB generally proposes, the effect of the background factors on intentions was not fully mediated by the proximal constructs of intentions. For instance, in the final model (Model#6), both factors had significant multiple indirect effect on INTV (β = .074, 95% C = .030, .126 [AHA:INTV]; β = .101, 95% C = .055, .155 [AUA:INTV]) and significant direct effect on INTV (β = .175, p < .001 [AHA:INTV]; β = .100, p = .003 [AUA:INTV]). Furthermore, the addition of direct paths from background factors to intentions improved the explained variance in intention (R2 = .324; R2Adj = .317) and the predictive relevance (Q2 = .300) over the base-model. This supports existing literature on the superiority of enhanced TPB models to predict ethical issues; which suggests that moral behavior may add additional complexity to decision-making. Regarding gender effect, MGA showed that gender only moderated the influence of AHA on ATTV (e.g., βWomen−βMen = .296, p < .001 [Model #6]). However, other observed gender differences (e.g. the explained variance of the model for intentions were always higher for men that for women, for instance, R2Women = .298; R2Men = .394 [Model #6]) deserve further considerations, especially for developing more effective communication strategies.Keywords: veganism, Theory of Planned Behavior, background factors, gender moderation
Procedia PDF Downloads 3503324 Delamination Fracture Toughness Benefits of Inter-Woven Plies in Composite Laminates Produced through Automated Fibre Placement
Authors: Jayden Levy, Garth M. K. Pearce
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An automated fibre placement method has been developed to build through-thickness reinforcement into carbon fibre reinforced plastic laminates during their production, with the goal of increasing delamination fracture toughness while circumventing the additional costs and defects imposed by post-layup stitching and z-pinning. Termed ‘inter-weaving’, the method uses custom placement sequences of thermoset prepreg tows to distribute regular fibre link regions in traditionally clean ply interfaces. Inter-weaving’s impact on mode I delamination fracture toughness was evaluated experimentally through double cantilever beam tests (ASTM standard D5528-13) on [±15°]9 laminates made from Park Electrochemical Corp. E-752-LT 1/4” carbon fibre prepreg tape. Unwoven and inter-woven automated fibre placement samples were compared to those of traditional laminates produced from standard uni-directional plies of the same material system. Unwoven automated fibre placement laminates were found to suffer a mostly constant 3.5% decrease in mode I delamination fracture toughness compared to flat uni-directional plies. Inter-weaving caused significant local fracture toughness increases (up to 50%), though these were offset by a matching overall reduction. These positive and negative behaviours of inter-woven laminates were respectively found to be caused by fibre breakage and matrix deformation at inter-weave sites, and the 3D layering of inter-woven ply interfaces providing numerous paths of least resistance for crack propagation.Keywords: AFP, automated fibre placement, delamination, fracture toughness, inter-weaving
Procedia PDF Downloads 1853323 Factor Structure of the Korean Version of Multidimensional Experiential Avoidance Questionnaire (MEAQ)
Authors: Juyeon Lee, Sungeun You
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Experiential avoidance is one’s tendency to avoid painful internal experience, unwanted adverse thoughts, emotions, and physical sensations. The Multidimensional Experiential Avoidance Questionnaire (MEAQ) is a measure of experiential avoidance, and the original scale consisted of 62 items with six subfactors including behavioral avoidance, distress aversion, procrastination, distraction/suppression, repression/denial, and distress endurance. The purpose of this study was to examine the factor structure of the MEAQ in a Korean sample. Three hundred community adults and university students aged 18 to 35 participated in an online survey assessing experiential avoidance (MEAQ and Acceptance and Action Questionnaire-II; AAQ-II), depression (Patient Health Questionnaire-9; PHQ-9), anxiety (Generalized Anxiety Disoder-7; GAD-7), negative affect (Positive and Negative Affect Scale; PANAS), neuroticism (Big Five Inventory; BFI), and quality of life (Satisfaction with Life Scale; SWLS). Factor analysis with principal axis with direct oblimin rotation was conducted to examine subfactors of the MEAQ. Results indicated that the six-factor structure of the original scale was adequate. Eight items out of 62 items were removed due to insufficient factor loading. These items included 3 items of behavior avoidance (e.g., “When I am hurting, I would do anything to feel better”), 2 items of repression/denial (e.g., “I work hard to keep out upsetting feelings”), and 3 items of distress aversion (e.g., “I prefer to stick to what I am comfortable with, rather than try new activities”). The MEAQ was positively associated with the AAQ-II (r = .47, p < .001), PHQ-9 (r = .37, p < .001), GAD-7 (r = .34, p < .001), PANAS (r = .35, p < .001), and neuroticism (r = .24, p < .001), and negatively correlated with the SWLS (r = -.38, p < .001). Internal consistency was good for the MEAQ total (Cronbach’s α = .90) as well as all six subfactors (Cronbach’s α = .83 to .87). The findings of the study support the multidimensional feature of experiential avoidance and validity of the MEAQ in a sample of Korean adults.Keywords: avoidance, experiential avoidance, factor structure, MEAQ
Procedia PDF Downloads 3673322 Cinema and the Documentation of Mass Killings in Third World Countries: A Study of Selected African Films
Authors: Chijindu D. Mgbemere
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Mass killing also known as genocide is the systematic killing of people from national, ethnic, or religious group, or an attempt to do so. The act has been there before 1948, when it was officially recognized for what it is. From then, the world has continued to witness genocide in diverse forms- negating different measures by the United Nations and its agencies to curb it. So far, all the studies and documentations on this subject are biased in favor of radio and the print. This paper therefore extended the interrogation of genocide, drumming its devastating effects, using the film medium; and in doing so devised innovative and pragmatic approach to genocide scholarship. It further centered attention on the factors and impacts of genocide, with a view to determine how effective film can be in such a study. The study is anchored on Bateson’s Framing Theory. Four films- Hotel Rwanda, Half of a Yellow Sun, Attack on Darfur, and sarafina, were analyzed, based on background, factors/causes, impacts, and development of genocide, via Content Analysis. The study discovered that: as other continents strive towards peace, acts of genocide are on the increase in African. Bloodletting stereotypes give Africa negative image in the global society. Difficult political frameworks, the trauma of postcolonial state, aggravated by ethnic and religious intolerance, and limited access to resources are responsible for high cases of genocide in Africa. The media, international communities, and peace agencies often abet other than prevent genocide or mass killings in Africa. High human casualty and displacement, children soldering, looting, hunger, rape, sex-slavery and abuse, mental and psychosomatic stress disorders are some of the impacts of genocide. Genocidaires are either condemned or killed. Grievances can be vented using civil resistance, negotiation, adjudication, arbitration, and mediation. The cinema is an effective means of studying and documenting genocide. Africans must factor the image laundering of their continent into consideration. Punishment of genocidaires without an attempt to de-radicalize them is counterproductive.Keywords: African film, genocide, framing theory, mass murder
Procedia PDF Downloads 1203321 Design of a 4-DOF Robot Manipulator with Optimized Algorithm for Inverse Kinematics
Authors: S. Gómez, G. Sánchez, J. Zarama, M. Castañeda Ramos, J. Escoto Alcántar, J. Torres, A. Núñez, S. Santana, F. Nájera, J. A. Lopez
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This paper shows in detail the mathematical model of direct and inverse kinematics for a robot manipulator (welding type) with four degrees of freedom. Using the D-H parameters, screw theory, numerical, geometric and interpolation methods, the theoretical and practical values of the position of robot were determined using an optimized algorithm for inverse kinematics obtaining the values of the particular joints in order to determine the virtual paths in a relatively short time.Keywords: kinematics, degree of freedom, optimization, robot manipulator
Procedia PDF Downloads 4683320 Dynamic Response around Inclusions in Infinitely Inhomogeneous Media
Authors: Jinlai Bian, Zailin Yang, Guanxixi Jiang, Xinzhu Li
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The problem of elastic wave propagation in inhomogeneous medium has always been a classic problem. Due to the frequent occurrence of earthquakes, many economic losses and casualties have been caused, therefore, to prevent earthquake damage to people and reduce damage, this paper studies the dynamic response around the circular inclusion in the whole space with inhomogeneous modulus, the inhomogeneity of the medium is reflected in the shear modulus of the medium with the spatial position, and the density is constant, this method can be used to solve the problem of the underground buried pipeline. Stress concentration phenomena are common in aerospace and earthquake engineering, and the dynamic stress concentration factor (DSCF) is one of the main factors leading to material damage, one of the important applications of the theory of elastic dynamics is to determine the stress concentration in the body with discontinuities such as cracks, holes, and inclusions. At present, the methods include wave function expansion method, integral transformation method, integral equation method and so on. Based on the complex function method, the Helmholtz equation with variable coefficients is standardized by using conformal transformation method and wave function expansion method, the displacement and stress fields in the whole space with circular inclusions are solved in the complex coordinate system, the unknown coefficients are solved by using boundary conditions, by comparing with the existing results, the correctness of this method is verified, based on the superiority of the complex variable function theory to the conformal transformation, this method can be extended to study the inclusion problem of arbitrary shapes. By solving the dynamic stress concentration factor around the inclusions, the influence of the inhomogeneous parameters of the medium and the wavenumber ratio of the inclusions to the matrix on the dynamic stress concentration factor is analyzed. The research results can provide some reference value for the evaluation of nondestructive testing (NDT), oil exploration, seismic monitoring, and soil-structure interaction.Keywords: circular inclusions, complex variable function, dynamic stress concentration factor (DSCF), inhomogeneous medium
Procedia PDF Downloads 1383319 Impact of Aging on Fatigue Performance of Novel Hybrid HMA
Authors: Faizan Asghar, Mohammad Jamal Khattak
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Aging, in general, refers to changes in rheological characteristics of asphalt mixture due to changes in chemical composition over the course of construction and service life of the pavement. The main goal of this study was to investigate the impact of oxidation on fatigue characteristics of a novel HMA composite fabricated with a combination of crumb rubber (CRM) and polyvinyl alcohol (PVA) fiber subject to aging of 7 and 14 days. A flexural beam fatigue test was performed to evaluate several characteristics of control, CRM modified, PVA reinforced, and novel rubber-fiber HMA composite. Experimental results revealed that aging had a significant impact on the fatigue performance of novel HMA composite. It was found that a suitable proportion of CRM and PVA radically affected the performance of novel rubber-fiber HMA in resistance to fracture and fatigue cracking when subjected to long-term aging. The developed novel HMA composite containing 2% CRM and 0.2% PVA presented around 29 times higher resistance to fatigue cracking for a period of 7 days of aging. To develop a cumulative plastic deformation level of 250 micros, such a mixture required over 50 times higher cycles than control HMA. Moreover, the crack propagation rate was reduced by over 90%, with over 12 times higher energy required to propagate a unit crack length in such a mixture compared to conventional HMA. Further, digital imaging correlation analyses revealed a more twisted and convoluted fracture path and higher strain distribution in rubber-fiber HMA composite. The fatigue performance after long-term aging of such novel HMA composite explicitly validates the ability to withstand load repetition that could lead to an extension in the service life of pavement infrastructure and reduce taxpayers’ dollars spent.Keywords: crumb rubber, PVA fibers, dry process, aging, performance testing, fatigue life
Procedia PDF Downloads 703318 A New Formulation Of The M And M-theta Integrals Generalized For Virtual Crack Closure In A Three-dimensional Medium
Authors: Loïc Chrislin Nguedjio, S. Jerome Afoutou, Rostand Moutou Pitti, Benoit Blaysat, Frédéric Dubois, Naman Recho, Pierre Kisito Talla
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The safety and durability of structures remain challenging fields that continue to draw the attention of designers. One widely adopted approach is fracture mechanics, which provides methods to evaluate crack stability in complex geometries and under diverse loading conditions. The global energy approach is particularly comprehensive, as it calculates the energy release rate required for crack initiation and propagation using path-independent integrals. This study aims to extend these invariant integrals to include path-independent integrals, with the goal of enhancing the accuracy of failure predictions. The ultimate objective is to create more robust materials while optimizing structural safety and durability. By integrating the real and virtual field method with the virtual crack closure technique, a new formulation of the M-integral is introduced. This formulation establishes a direct relationship between local stresses on the crack faces and the opening displacements, allowing for an accurate calculation of fracture energy. The analytical calculations are grounded in the assumption that the energy needed to close a crack virtually is equal to the energy released during its opening. This novel integral is implemented in a finite element code using Cast3M to simulate cracking criteria within a wood material context. Initially, the numerical calculations are focused on plane strain conditions, but they are later extended to three-dimensional environments, taking into account the orthotropic nature of wood.Keywords: energy release rate, path-independent integrals, virtual crack closure, orthotropic material
Procedia PDF Downloads 163317 Some Considerations about the Theory of Spatial-Motor Thinking Applied to a Traditional Fife Band in Brazil
Authors: Murilo G. Mendes
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This text presents part of the results presented in the Ph.D. thesis that has used John Baily's theory and method as well as its ethnographic application in the context of the fife flutes of the Banda Cabaçal dos Irmãos Aniceto in the state of Ceará, northeast of Brazil. John Baily is a British ethnomusicologist dedicated to studying the relationships between music, musical gesture, and embodied cognition. His methodology became a useful tool to highlight historical-social aspects present in the group's instrumental music. Remaining indigenous and illiterate, these musicians played and transmitted their music from generation to generation, for almost two hundred years, without any nomenclature or systematization of the fingering performed on the flute. In other words, his music, free from any theorization, is learned, felt, perceived, and processed directly through hearing and through the relationship between the instrument's motor skills and its sound result. For this reason, Baily's assumptions became fundamental in the analysis processes. As the author's methodology recommends, classes were held with the natives and provided technical musical learning and some important concepts. Then, transcriptions and analyses of musical aspects were made from patterns of movement on the instrument incorporated by repetitions and/or by the intrinsic facility of the instrument. As a result, it was discovered how the group reconciled its indigenous origins with the demand requested by the public power and the interests of the local financial elite from the mid-twentieth century. The article is structured from the cultural context of the group, where local historical and social aspects influence the social and musical practices of the group. Then, will be present the methodological conceptions of John Baily and, finally, their application in the music of the Irmãos Aniceto. The conclusion points to the good results of identifying, through this methodology and analysis, approximations between discourse, historical-social factors, and musical text. Still, questions are raised about its application in other contexts.Keywords: Banda Cabaçal dos Irmãos Aniceto, John Baily, pífano, spatial-motor thinking
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