Search results for: structural break
3676 Long-Term Structural Behavior of Resilient Materials for Reduction of Floor Impact Sound
Authors: Jung-Yoon Lee, Jongmun Kim, Hyo-Jun Chang, Jung-Min Kim
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People’s tendency towards living in apartment houses is increasing in a densely populated country. However, some residents living in apartment houses are bothered by noise coming from the houses above. In order to reduce noise pollution, the communities are increasingly imposing a bylaw, including the limitation of floor impact sound, minimum thickness of floors, and floor soundproofing solutions. This research effort focused on the specific long-time deflection of resilient materials in the floor sound insulation systems of apartment houses. The experimental program consisted of testing nine floor sound insulation specimens subjected to sustained load for 45 days. Two main parameters were considered in the experimental investigation: three types of resilient materials and magnitudes of loads. The test results indicated that the structural behavior of the floor sound insulation systems under long-time load was quite different from that the systems under short-time load. The loading period increased the deflection of floor sound insulation systems and the increasing rate of the long-time deflection of the systems with ethylene vinyl acetate was smaller than that of the systems with low density ethylene polystyrene.Keywords: resilient materials, floor sound insulation systems, long-time deflection, sustained load, noise pollution
Procedia PDF Downloads 2693675 Potential Antibacterial Applications and Synthesis, Structural, Magnetic, Optical, and Dielectric Characterization of Nickel-Substituted Cobalt Ferrite Nanoparticles
Authors: Tesfay Gebremichael Reda
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Nanoparticle technology is fast progressing and is being employed in innumerable medical applications. At this time, the public's health is seriously threatened by the rise of bacterial strains resistant to several medications. Metal nanoparticles are a potential alternate approach for tackling this global concern, and this is the main focus of this study. The citrate precursor sol-gel synthesis method was used to synthesize the, Niₓ Co(₁-ₓ) Fe₂ O₄, (where x = 0.0:0.2:1.0) nanoparticle. XRD identified the development of the cubic crystal structure to have a preferential orientation along (311), and the average particle size was found to be 29-38 nm. The average crystallizes assessed with ImageJ software and origin 22 of the SEM are nearly identical to the XRD results. In the created NCF NPs, the FT-IR spectroscopy reveals structural examinations and the redistribution of cations between octahedral (505-428 cm-1) and tetrahedral (653-603 cm-1) locales. Finally, the decrease of coercive fields HC, 2384 Oe to 241.93 Oe replacement of Co²+ cation with Ni²+. Band gap energy rises as Ni concentration increases, which may be attributed to the fact that the ionic radii of Ni²+ ions are smaller than that of Co²+ ions, which results in a strong electrostatic interaction. On the contrary, except at x = 0.4, the dielectric constant decreases as the nickel concentration increases. According to the findings of this research work, nanoparticles composed of Ni₀.₄ Co₀.₄ Fe₂ O₄ have demonstrated a promising value against S. aureus and E. coli, and it suggests a proposed model for their potential use as a new source of antibacterial agents.Keywords: antimicrobial, band gap, citrate precursor, dielectric, nanoparticle
Procedia PDF Downloads 303674 Analyzing How Working From Home Can Lead to Higher Job Satisfaction for Employees Who Have Care Responsibilities Using Structural Equation Modeling
Authors: Christian Louis Kühner, Florian Pfeffel, Valentin Nickolai
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Taking care of children, dependents, or pets can be a difficult and time-consuming task. Especially for part- and full-time employees, it can feel exhausting and overwhelming to meet these obligations besides working a job. Thus, working mostly at home and not having to drive to the company can save valuable time and stress. This study aims to show the influence that the working model has on the job satisfaction of employees with care responsibilities in comparison to employees who do not have such obligations. Using structural equation modeling (SEM), the three work models, “work from home”, “working remotely”, and a hybrid model, have been analyzed based on 13 influencing constructs on job satisfaction. These 13 factors have been further summarized into three groups “classic influencing factors”, “influencing factors changed by remote working”, and “new remote working influencing factors”. Based on the influencing factors on job satisfaction, an online survey was conducted with n = 684 employees from the service sector. Here, Cronbach’s alpha of the individual constructs was shown to be suitable. Furthermore, the construct validity of the constructs was confirmed by face validity, content validity, convergent validity (AVE > 0.5: CR > 0.7), and discriminant validity. In addition, confirmatory factor analysis (CFA) confirmed the model fit for the investigated sample (CMIN/DF: 2.567; CFI: 0.927; RMSEA: 0.048). The SEM-analysis has shown that the most significant influencing factor on job satisfaction is “identification with the work” with β = 0.540, followed by “Appreciation” (β = 0.151), “Compensation” (β = 0.124), “Work-Life-Balance” (β = 0.116), and “Communication and Exchange of Information” (β = 0.105). While the significance of each factor can vary depending on the work model, the SEM-analysis shows that the identification with the work is the most significant factor in all three work models and, in the case of the traditional office work model, it is the only significant influencing factor. The study shows that among the employees with care responsibilities, the higher the proportion of working from home in comparison to working from the office, the more satisfied the employees are with their job. Since the work models that meet the requirements of comprehensive care led to higher job satisfaction amongst employees with such obligations, adapting as a company to such private obligations by employees can be crucial to sustained success. Conversely, the satisfaction level of the working model where employees work at the office is higher for workers without caregiving responsibilities.Keywords: care responsibilities, home office, job satisfaction, structural equation modeling
Procedia PDF Downloads 853673 Investigation of Physical Properties of W-Doped CeO₂ and Mo-Doped CeO₂: A Density Functional Theory Study
Authors: Aicha Bouhlala, Sabah Chettibi
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A systematic investigation on structural, electronic, and magnetic properties of Ce₀.₇₅A₀.₂₅O₂ (A = W, Mo) is performed using first-principles calculations within the framework Full-Potential Linear Augmented Plane Wave (FP-LAPW) method based on the Density Functional Theory (DFT). The exchange-correlation potential has been treated using the generalized gradient approximation (WC-GGA) developed by Wu-Cohen. The host compound CeO2 was doped with transition metal atoms W and Mo in the doping concentration of 25% to replace the Ce atom. In structural properties, the equilibrium lattice constant is observed for the W-doped CeO₂ compound which exists within the value of 5.314 A° and the value of 5.317 A° for Mo-doped CeO2. The present results show that Ce₀.₇₅A₀.₂₅O₂ (A=W, Mo) systems exhibit semiconducting behavior in both spin channels. Although undoped CeO₂ is a non-magnetic semiconductor. The band structure of these doped compounds was plotted and they exhibit direct band gap at the Fermi level (EF) in the majority and minority spin channels. In the magnetic properties, the doped atoms W and Mo play a vital role in increasing the magnetic moments of the supercell and the values of the total magnetic moment are found to be 1.998 μB for Ce₀.₇₅W₀.₂₅O₂ and to be 2.002 μB for Ce₀.₇₅Mo₀.₂₅O₂ compounds. Calculated results indicate that the magneto-electronic properties of the Ce₁₋ₓAₓO₂(A= W, Mo) oxides supply a new way to the experimentalist for the potential applications in spintronics devices.Keywords: FP-LAPW, DFT, CeO₂, properties
Procedia PDF Downloads 2173672 Sensitivity Analysis of Pile-Founded Fixed Steel Jacket Platforms
Authors: Mohamed Noureldin, Jinkoo Kim
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The sensitivity of the seismic response parameters to the uncertain modeling variables of pile-founded fixed steel jacket platforms are investigated using tornado diagram, first-order second-moment, and static pushover analysis techniques. The effects of both aleatory and epistemic uncertainty on seismic response parameters have been investigated for an existing offshore platform. The sources of uncertainty considered in the present study are categorized into three different categories: the uncertainties associated with the soil-pile modeling parameters in clay soil, the platform jacket structure modeling parameters, and the uncertainties related to ground motion excitations. It has been found that the variability in parameters such as yield strength or pile bearing capacity has almost no effect on the seismic response parameters considered, whereas the global structural response is highly affected by the ground motion uncertainty. Also, some uncertainty in soil-pile property such as soil-pile friction capacity has a significant impact on the response parameters and should be carefully modeled. Based on the results, it is highlighted that which uncertain parameters should be considered carefully and which can be assumed with reasonable engineering judgment during the early structural design stage of fixed steel jacket platforms.Keywords: fixed jacket offshore platform, pile-soil structure interaction, sensitivity analysis
Procedia PDF Downloads 3763671 Expectation-Confirmation Model of Information System Continuance: A Meta-Analysis
Authors: Hui-Min Lai, Chin-Pin Chen, Yung-Fu Chang
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The expectation-confirmation model (ECM) is one of the most widely used models for evaluating information system continuance, and this model has been extended to other study backgrounds, or expanded with other theoretical perspectives. However, combining ECM with other theories or investigating the background problem may produce some disparities, thus generating inaccurate conclusions. Habit is considered to be an important factor that influences the user’s continuance behavior. This paper thus critically examines seven pairs of relationships from the original ECM and the habit variable. A meta-analysis was used to tackle the development of ECM research over the last 10 years from a range of journals and conference papers published in 2005–2014. Forty-six journal articles and 19 conference papers were selected for analysis. The results confirm our prediction that a high effect size for the seven pairs of relationships was obtained (ranging from r=0.386 to r=0.588). Furthermore, a meta-analytic structural equation modeling was performed to simultaneously test all relationships. The results show that habit had a significant positive effect on continuance intention at p<=0.05 and that the six other pairs of relationships were significant at p<0.10. Based on the findings, we refined our original research model and an alternative model was proposed for understanding and predicting information system continuance. Some theoretical implications are also discussed.Keywords: Expectation-confirmation theory, Expectation-confirmation model, Meta-analysis, meta-analytic structural equation modeling.
Procedia PDF Downloads 3093670 Computational, Human, and Material Modalities: An Augmented Reality Workflow for Building form Found Textile Structures
Authors: James Forren
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This research paper details a recent demonstrator project in which digital form found textile structures were built by human craftspersons wearing augmented reality (AR) head-worn displays (HWDs). The project utilized a wet-state natural fiber / cementitious matrix composite to generate minimal bending shapes in tension which, when cured and rotated, performed as minimal-bending compression members. The significance of the project is that it synthesizes computational structural simulations with visually guided handcraft production. Computational and physical form-finding methods with textiles are well characterized in the development of architectural form. One difficulty, however, is physically building computer simulations: often requiring complicated digital fabrication workflows. However, AR HWDs have been used to build a complex digital form from bricks, wood, plastic, and steel without digital fabrication devices. These projects utilize, instead, the tacit knowledge motor schema of the human craftsperson. Computational simulations offer unprecedented speed and performance in solving complex structural problems. Human craftspersons possess highly efficient complex spatial reasoning motor schemas. And textiles offer efficient form-generating possibilities for individual structural members and overall structural forms. This project proposes that the synthesis of these three modalities of structural problem-solving – computational, human, and material - may not only develop efficient structural form but offer further creative potentialities when the respective intelligence of each modality is productively leveraged. The project methodology pertains to its three modalities of production: 1) computational, 2) human, and 3) material. A proprietary three-dimensional graphic statics simulator generated a three-legged arch as a wireframe model. This wireframe was discretized into nine modules, three modules per leg. Each module was modeled as a woven matrix of one-inch diameter chords. And each woven matrix was transmitted to a holographic engine running on HWDs. Craftspersons wearing the HWDs then wove wet cementitious chords within a simple falsework frame to match the minimal bending form displayed in front of them. Once the woven components cured, they were demounted from the frame. The components were then assembled into a full structure using the holographically displayed computational model as a guide. The assembled structure was approximately eighteen feet in diameter and ten feet in height and matched the holographic model to under an inch of tolerance. The construction validated the computational simulation of the minimal bending form as it was dimensionally stable for a ten-day period, after which it was disassembled. The demonstrator illustrated the facility with which computationally derived, a structurally stable form could be achieved by the holographically guided, complex three-dimensional motor schema of the human craftsperson. However, the workflow traveled unidirectionally from computer to human to material: failing to fully leverage the intelligence of each modality. Subsequent research – a workshop testing human interaction with a physics engine simulation of string networks; and research on the use of HWDs to capture hand gestures in weaving seeks to develop further interactivity with rope and chord towards a bi-directional workflow within full-scale building environments.Keywords: augmented reality, cementitious composites, computational form finding, textile structures
Procedia PDF Downloads 1773669 Chemical, Structural and Mechanical Optimization of Zr-Based Bulk Metallic Glass for Biomedical Applications
Authors: Eliott Guérin, Remi Daudin, Georges Kalepsi, Alexis Lenain, Sebastien Gravier, Benoit Ter-Ovanessian, Damien Fabregue, Jean-Jacques Blandin
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Due to interesting compromise between mechanical and corrosion properties, Zr-based BMGs are attractive for biomedical applications. However, the enhancement of their glass forming ability (GFA) is often achieved by addition of toxic elements like Ni or Be, which is of course a problem for such applications. Consequently, the development of Ni-free Be-free Zr-based BMGs is of great interest. We have developed a Zr-based (Ni and Be-free) amorphous metallic alloy with an elastic limit twice the one of Ti-6Al-4V. The Zr56Co28Al16 composition exhibits a yield strength close to 2 GPa and low Young’s modulus (close to 90 GPa) [1-2]. In this work, we investigated Niobium (Nb) addition through substitution of Zr up to 8 at%. Cobalt substitution has already been reported [3], but we chose Zr substitution to preserve the glass forming ability. In this case, we show that the glass forming ability for 5 mm diameters rods is maintained up to 3 at% of Nb substitution using suction casting in cooper moulds. Concerning the thermal stability, we measure a strong compositional dependence on the glass transition (Tg). Using DSC analysis (heating rate 20 K/min), we show that the Tg rises from 752 K for 0 at% of Nb to 759 K for 3 at% of Nb. Yet, the thermal range between Tg and the crystallisation temperature (Tx) remains almost unchanged from 33 K to 35 K. Uniaxial compression tests on 2 mm diameter pillars and 3 points bending (3PB) tests on 1 mm thick plates are performed to study the Nb addition on the mechanical properties and the plastic behaviour. With these tests, an optimal Nb concentration is found, improving both plasticity and fatigue resistance. Through interpretations of DSC measurements, an attempt is made to correlate the modifications of the mechanical properties with the structural changes. The optimized chemical, structural and mechanical properties through Nb addition are encouraging to develop the potential of this BMG alloy for biomedical applications. For this purpose, we performed polarisation, immersion and cytotoxicity tests. The figure illustrates the polarisation response of Zr56Co28Al16, Zr54Co28Al16Nb2 and TA6V as a reference after 2h of open circuit potential. The results show that the substitution of Zr by a small amount of Nb significantly improves the corrosion resistance of the alloy.Keywords: metallic glasses, amorphous metal, medical, mechanical resistance, biocompatibility
Procedia PDF Downloads 1513668 Study on High Performance Fiber Reinforced Concrete (HPFRC) Beams on Subjected to Cyclic Loading
Authors: A. Siva, K. Bala Subramanian, Kinson Prabu
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Concrete is widely used construction materials all over the world. Now a day’s fibers are used in this construction due to its advantages like increase in stiffness, energy absorption, ductility and load carrying capacity. The fiber used in the concrete to increases the structural integrity of the member. It is one of the emerging techniques used in the construction industry. In this paper, the effective utilization of high-performance fiber reinforced concrete (HPFRC) beams has been experimental investigated. The experimental investigation has been conducted on different steel fibers (Hooked, Crimpled, and Hybrid) under cyclic loading. The behaviour of HPFRC beams is compared with the conventional beams. Totally four numbers of specimens were cast with different content of fiber concrete and compared conventional concrete. The fibers are added to the concrete by base volume replacement of concrete. The silica fume and superplasticizers were used to modify the properties of concrete. Single point loading was carried out for all the specimens, and the beam specimens were subjected to cyclic loading. The load-deflection behaviour of fibers is compared with the conventional concrete. The ultimate load carrying capacity, energy absorption and ductility of hybrid fiber reinforced concrete is higher than the conventional concrete by 5% to 10%.Keywords: cyclic loading, ductility, high performance fiber reinforced concrete, structural integrity
Procedia PDF Downloads 2773667 Gendered Mobility: Deep Distributions in Urban Transport Systems in Delhi
Authors: Nidhi Prabha
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Transportation as a sector is one of the most significant infrastructural elements of the ‘urban.' The distinctness of an urban life in a city is marked by the dynamic movements that it enables within the city-space. Therefore it is important to study the public-transport systems that enable and foster mobility which characterizes the urban. It is also crucial to underscore the way one is examining the urban transport systems - either as an infrastructural unit in a strict physical-structural sense or as a structural unit which acts as a prism refracting multiple experiences depending on the location of the ‘commuter.' In the proposed paper, the attempt is to uncover and investigate the assumption of the neuter-commuter by looking at urban transportation in the secondary sense i.e. as a structural unit which is experienced differently by different kinds of commuters, thus making transportation deeply distributed with various social structures and locations like class or gender which map onto the transport systems. To this end, the public-transit systems operating in Urban Delhi i.e. the Delhi Metros and the Delhi Transport Corporation run public-buses are looked at as case studies. The study is premised on the knowledge and data gained from both primary and secondary sources. Primary sources include data and knowledge collected from fieldwork, the methodology for which has ranged from adopting ‘mixed-methods’ which is ‘Qualitative-then-Quantitative’ as well as borrowing ethnographic techniques. Apart from fieldwork, other primary sources looked at including Annual Reports and policy documents of the Delhi Metro Rail Corporation (DMRC) and the Delhi Transport Corporation (DTC), Union and Delhi budgets, Economic Survey of Delhi, press releases, etc. Secondary sources include the vast array of literature available on the critical nodes that inform the research like gender, transport geographies, urban-space, etc. The study indicates a deeply-distributed urban transport system wherein the various social-structural locations or different kinds of commuters map onto the way these different commuters experience mobility or movement within the city space. Mobility or movement, therefore, becomes gendered or has class-based ramifications. The neuter-commuter assumption is thus challenged. Such an understanding enables us to challenge the anonymity which the ‘urban’ otherwise claims it provides over the rural. The rural is opposed to the urban wherein urban ushers a modern way of life, breaking ties of traditional social identities. A careful study of the transport systems through the traveling patterns and choices of the commuters, however, indicate that this does not hold true as even the same ‘public-space’ of the transport systems allocates different places to different kinds of commuters. The central argument made though the research done is therefore that infrastructure like urban-transport-systems has to be studied and examined as seen beyond just a physical structure. The various experiences of daily mobility of different kinds of commuters have to be taken into account in order to design and plan more inclusive transport systems.Keywords: gender, infrastructure, mobility, urban-transport-systems
Procedia PDF Downloads 2313666 Loop Heat Pipe Two-Phase Heat Transports: Guidelines for Technology Utilization
Authors: Triem T. Hoang
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Loop heat pipes (LHPs) are two-phase capillary-pumped heat transports. An appropriate working fluid is selected for the intended application temperature range. A closed-loop is evacuated to a high vacuum, back-filled partially with the working fluid, and then hermetically sealed under the fluid own pressure. Heat from a heat source conducts through the evaporator casing to vaporize liquid on the outer surface of the wick structure inside the evaporator. The generated vapor is compelled to vent out of the evaporator and into the vapor line for transport to the condenser assembly. There, heat is removed and rejected to a heat sink to condensed vapor back to liquid. The liquid exits the condenser and travels in the liquid line to return to the evaporator to complete the cycle. The circulation of fluid, and thus the heat transport in the LHP, is accomplished entirely by capillary action. The LHP contains no mechanical moving part to wear out or break down and, therefore possesses, reliability and a long life even without maintenance. In this paper, the author not only attempts to introduce the LHP technology in simplistic terms to those who are not familiar with it but also provides necessary technical information to potential users for the proper design and analysis of the LHP system.Keywords: two-phase heat transfer, loop heat pipe, capillary pumped technology, thermal-fluid modeling
Procedia PDF Downloads 1413665 Evaluation of the Factors Affecting Violence Against Women (Case Study: Couples Referring to Family Counseling Centers in Tehran)
Authors: Hassan Manouchehri
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The present study aimed to identify and evaluate the factors affecting violence against women. The statistical population included all couples referring to family counseling centers in Tehran due to domestic violence during the past year. A number of 305 people were selected as a statistical sample using simple random sampling and Cochran's formula in unlimited conditions. A researcher-made questionnaire including 110 items was used for data collection. The face validity and content validity of the questionnaire were confirmed by 30 experts and its reliability was obtained above 0.7 for all studied variables in a preliminary test with 30 subjects and it was acceptable. In order to analyze the data, descriptive statistical methods were used with SPSS software version 22 and inferential statistics were used for modeling structural equations in Smart PLS software version 2. Evaluating the theoretical framework and domestic and foreign studies indicated that, in general, four main factors, including cultural and social factors, economic factors, legal factors, as well as medical factors, underlie violence against women. In addition, structural equation modeling findings indicated that cultural and social factors, economic factors, legal factors, and medical factors affect violence against women.Keywords: violence against women, cultural and social factors, economic factors, legal factors, medical factors
Procedia PDF Downloads 1433664 A Causal Model for Environmental Design of Residential Community for Elderly Well-Being in Thailand
Authors: Porntip Ruengtam
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This article is an extension of previous research presenting the relevant factors related to environmental perceptions, residential community, and the design of a healing environment, which have effects on the well-being and requirements of Thai elderly. Research methodology began with observations and interviews in three case studies in terms of the management processes and environment design of similar existing projects in Thailand. The interview results were taken to summarize with related theories and literature. A questionnaire survey was designed for data collection to confirm the factors of requirements in a residential community intended for the Thai elderly. A structural equation model (SEM) was formulated to explain the cause-effect factors for the requirements of a residential community for Thai elderly. The research revealed that the requirements of a residential community for Thai elderly were classified into three groups when utilizing a technique for exploratory factor analysis. The factors were comprised of (1) requirements for general facilities and activities, (2) requirements for facilities related to health and security, and (3) requirements for facilities related to physical exercise in the residential community. The results from the SEM showed the background of elderly people had a direct effect on their requirements for a residential community from various aspects. The results should lead to the formulation of policies for design and management of residential communities for the elderly in order to enhance quality of life as well as both the physical and mental health of the Thai elderly.Keywords: elderly, environmental design, residential community, structural equation modeling
Procedia PDF Downloads 3143663 Numerical Investigation of Beam-Columns Subjected to Non-Proportional Loadings under Ambient Temperature Conditions
Authors: George Adomako Kumi
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The response of structural members, when subjected to various forms of non-proportional loading, plays a major role in the overall stability and integrity of a structure. This research seeks to present the outcome of a finite element investigation conducted by the use of finite element programming software ABAQUS to validate the experimental results of elastic and inelastic behavior and strength of beam-columns subjected to axial loading, biaxial bending, and torsion under ambient temperature conditions. The application of the rigorous and highly complicated ABAQUS finite element software will seek to account for material, non-linear geometry, deformations, and, more specifically, the contact behavior between the beam-columns and support surfaces. Comparisons of the three-dimensional model with the results of actual tests conducted and results from a solution algorithm developed through the use of the finite difference method will be established in order to authenticate the veracity of the developed model. The results of this research will seek to provide structural engineers with much-needed knowledge about the behavior of steel beam columns and their response to various non-proportional loading conditions under ambient temperature conditions.Keywords: beam-columns, axial loading, biaxial bending, torsion, ABAQUS, finite difference method
Procedia PDF Downloads 1823662 Structural Analysis of a Composite Wind Turbine Blade
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The design of an optimised horizontal axis 5-meter-long wind turbine rotor blade in according with IEC 61400-2 standard is a research and development project in order to fulfil the requirements of high efficiency of torque from wind production and to optimise the structural components to the lightest and strongest way possible. For this purpose, a research study is presented here by focusing on the structural characteristics of a composite wind turbine blade via finite element modelling and analysis tools. In this work, first, the required data regarding the general geometrical parts are gathered. Then, the airfoil geometries are created at various sections along the span of the blade by using CATIA software to obtain the two surfaces, namely; the suction and the pressure side of the blade in which there is a hat shaped fibre reinforced plastic spar beam, so-called chassis starting at 0.5m from the root of the blade and extends up to 4 m and filled with a foam core. The root part connecting the blade to the main rotor differential metallic hub having twelve hollow threaded studs is then modelled. The materials are assigned as two different types of glass fabrics, polymeric foam core material and the steel-balsa wood combination for the root connection parts. The glass fabrics are applied using hand wet lay-up lamination with epoxy resin as METYX L600E10C-0, is the unidirectional continuous fibres and METYX XL800E10F having a tri-axial architecture with fibres in the 0,+45,-45 degree orientations in a ratio of 2:1:1. Divinycell H45 is used as the polymeric foam. The finite element modelling of the blade is performed via MSC PATRAN software with various meshes created on each structural part considering shell type for all surface geometries, and lumped mass were added to simulate extra adhesive locations. For the static analysis, the boundary conditions are assigned as fixed at the root through aforementioned bolts, where for dynamic analysis both fixed-free and free-free boundary conditions are made. By also taking the mesh independency into account, MSC NASTRAN is used as a solver for both analyses. The static analysis aims the tip deflection of the blade under its own weight and the dynamic analysis comprises normal mode dynamic analysis performed in order to obtain the natural frequencies and corresponding mode shapes focusing the first five in and out-of-plane bending and the torsional modes of the blade. The analyses results of this study are then used as a benchmark prior to modal testing, where the experiments over the produced wind turbine rotor blade has approved the analytical calculations.Keywords: dynamic analysis, fiber reinforced composites, horizontal axis wind turbine blade, hand-wet layup, modal testing
Procedia PDF Downloads 4273661 Teaching University Students Lateral Reading to Detect Disinformation and Misinformation
Authors: Diane Prorak, Perri Moreno
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University students may have been born in the digital age, but they need to be taught the critical thinking skills to detect misinformation and social media manipulation online. In recent years, librarians have been active in designing instructional methods to help students learn information evaluation skills. At the University of Idaho Library (USA), librarians have developed new teaching methods for these skills. Last academic year, when classes were taught via Zoom, librarians taught these skills to an online session of each first-year rhetoric and composition course. In the Zoom sessions, students were placed in breakout groups where they practiced using an evaluation method known as lateral reading. Online collaborative software was used to give each group an evaluative task and break the task into steps. Groups reported back to the full class. Students learned to look at an information source, then search outside the source to find information about the organization, publisher or author, before evaluating the source itself. Class level pre-and post-test comparison results showed students learned better techniques for evaluation than they knew before instruction.Keywords: critical thinking, information evaluation, information literacy instruction, lateral reading.
Procedia PDF Downloads 1823660 Green Natural Rubber Composites Reinforced with Synthetic Graphite: Effects of Reinforcing Agent on Film’s Mechanical Properties and Electrical Conductivity
Authors: Veerapat Kitsawat, Muenduen Phisalaphong
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Green natural rubber (NR) composites reinforced with synthetic graphite, using alginate as thickening and dispersing agent, were developed to improve mechanical properties and electrical conductivity. The film fabrication was performed using a latex aqueous microdispersion process. The research found that up to 60 parts per hundred rubbers (phr) of graphite could be successfully integrated into the NR matrix without causing agglomeration and phase separation. Accordingly, the mechanical properties, in terms of tensile strength and Young’s modulus of the composite films, were significantly increased, while the elongation at break decreased with higher graphite loading. The reinforcement strongly improved the hydrophilicity of the composite films, resulting in a higher water absorption rate compared to the neat NR film. Moreover, the incorporation of synthetic graphite significantly improved the chemical resistance of the composite films when exposed to toluene. It is demonstrated that the electrical conductivity of the composite films was considerably enhanced with graphite loading. According to the obtained properties, the developed composites offer potential for further development as conductive substrate for electronic applications.Keywords: alginate, composite, graphite, natural rubber
Procedia PDF Downloads 843659 Platooning Method Using Dynamic Correlation of Destination Vectors in Urban Areas
Authors: Yuya Tanigami, Naoaki Yamanaka, Satoru Okamoto
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Economic losses due to delays in traffic congestion regarding urban transportation networks have become a more serious social problem as traffic volume increases. Platooning has recently been attracting attention from many researchers to alleviate traffic jams, especially on the highway. On highways, platooning can have positive effects, such as reducing inter-vehicular distance and reducing air resistance. However, the impacts of platooning on urban roads have not been addressed in detail since traffic lights may break the platoons. In this study, we propose a platooning method using L2 norm and cosine similarity to form a platoon with highly similar routes. Also, we investigate the sorting method within a platoon according to each vehicle’s straightness. Our proposed sorting platoon method, which uses two lanes, eliminates Head of Line Blocking at the intersection and improves throughput at intersections. This paper proposes a cyber-physical system (CPS) approach to collaborative urban platoon control. We conduct simulations using the traffic simulator SUMO and the road network, which imitates Manhattan Island. Results from the SUMO confirmed that our method shortens the average travel time by 10-20%. This paper shows the validity of forming a platoon based on destination vectors and sorting vehicles within a platoon.Keywords: CPS, platooning, connected car, vector correlation
Procedia PDF Downloads 773658 Educating for Acceptance or Action: Bachelor of Social Work Education in Canada
Authors: Elizabeth Radian
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In a challenging era of neoliberalism and managerialism in social services, the status of Canadian social work education at the Bachelor of Social Work level (BSW) was examined to determine how prepared students were to practice in a time of resource cutbacks and insecurity. Curricula in BSW programs was the focus as this generalist degree results in the greatest number of social work graduates in Canada, most of whom work at the front lines in service delivery. The study reviewed the practice frameworks that students in BSW programs were exposed to. Traditionally, schools of social work have embraced two major practice frameworks. The person in environment framework is a well-established practice framework taught in most schools. The framework offers some focus on smaller scale social change, tweaking existing arrangements and is more accepting of the status quo. An alternate practice framework taught in fewer schools has been described as a structural, progressive or anti oppressive framework. This latter framework challenges the status quo, is focused on social justice and social transformation, often incorporating social action strategies to ensure marginalized voices are heard. Using a content analysis methodology of keywords and phrases to delineate framework orientation, practice frameworks articulated in the curricula were determined by reviewing the mission/mandate of schools offering a BSW degree, their core course outlines and core course textbooks. Social action, as one strategy for initiating social change and transformation was considered. Initial research for 28 schools was completed in 2000, with follow up replications of the initial study in 2005 and 2014. These earlier studies displayed that the dominant practice framework taught in BSW programs was the person in environment framework. A lesser number of schools were categorized as primarily offering a structural, progressive or anti oppressive framework. The findings from the current study of 39 Canadian schools of social work are considered to determine how prominent structural, progressive and anti oppressive frameworks exist in current BSW curricula. This study can assist in contemplating the question – are we educating future practitioners for acceptance or action.Keywords: social work education and pedagogy, social change, social justice, social services
Procedia PDF Downloads 1943657 Investigations of Flame Retardant Properties of Beneficiated Huntite and Hydromagnesite Mineral Reinforced Polymer Composites
Authors: H. Yilmaz Atay
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Huntite and hydromagnesite minerals have been used as additive materials to achieve incombustible material due to their inflammability property. Those fire retardants materials can help to extinguish in the early stages of fire. Thus dispersion of the flame can be prevented even if the fire started. Huntite and hydromagnesite minerals are known to impart fire-proofing of the polymer composites. However, the additives used in the applications led to deterioration in the mechanical properties due to the usage of high amount of the powders in the composites. In this study, by enriching huntite and hydromagnesite, it was aimed to use purer minerals to reinforce the polymer composites. Thus, predictably, using purer mineral will lead to use lower amount of mineral powders. By this manner, the minerals free from impurities by various processes were added to the polymer matrix with different loading level and grades. Different types of samples were manufactured, and subsequently characterized by XRD, SEM-EDS, XRF and flame-retardant tests. Tensile strength and elongation at break values were determined according to loading levels and grades. Besides, a comparison on the properties of the polymer composites produced by using of minerals with and without impurities was performed. As a result of the work, it was concluded that it is required to use beneficiated minerals to provide better fire-proofing behaviors in the polymer composites.Keywords: flame retardant, huntite and hydromagnesite, mechanical property, polymer composites
Procedia PDF Downloads 2413656 Sewage Sludge Management: A Case Study of Monrovia, Montserrado County, Liberia
Authors: Victor Emery David Jr, Md S. Hossain
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Sewage sludge management has been a problem faced by most developing cities as in the case of Monrovia. The management of sewage sludge in Monrovia is still in its infant stage. The city is still struggling with poor sanitation, clogged pipes, shortage of septic tanks, lack of resources/human capacity, inadequate treatment facilities, open defecation, the absence of clear guidelines, etc. The rapid urban population growth of Monrovia has severely stressed Monrovia’s marginally functional urban WSS system caused by the civil conflict which led to break down in many sectors as well as infrastructure. The sewerage system which originally covered 17% of the population of Monrovia was down to serving about 7% because of bursts and blockages causing backflows in other areas. Prior to the Civil War, the average water production for Monrovia was about 68,000 m3/day but has now dropped to about 10,000 m3/day. Only small parts of Monrovia currently have direct access to the piped water supply while most areas depend on trucked water delivered to community collection points or household tanks, and/or on water from unprotected dug wells or hand pumps. There are only two functional treatment plants; The Fiamah Treatment plant and the White Plains Treatment Plant.Keywords: Fiamah Treatment plant, management, Monrovia/Montserrado County, sewage, sludge
Procedia PDF Downloads 2903655 Clustering of Natural and Nature Derived Compounds for Cardiovascular Disease: Pharmacophore Modeling
Authors: S. Roy, R. Rekha, K. Sriram, G. Subhadra, R. Johana
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Cardiovascular disease remains a leading cause of death in most industrialized countries. Many chemical drugs are available in the market which targets different receptor proteins related to cardiovascular diseases. Of late the traditional herbal drugs are safer when compared to chemical drugs because of its side effects. However, many herbal remedies used in treating cardiovascular diseases have not undergone scientific assessment to prove its pharmacological activities. There are many natural compounds, nature derived and Natural product mimic compounds are available which are in the market as approved drug. In the most of the cases drug activity at the molecular level are not known. Here we have categorized those compounds with our experimental compounds in different classes based on the structural similarity and physicochemical properties, using a tool, Chemmine and has attempted to understand the mechanism of the action of a experimental compound, which are clustered with Simvastatin, Lovastatin, Mevastatin and Pravastatin. Target protein molecule for Simvastatin, Lovastatin, Mevastatin and Pravastatin is HMG-CoA reductase, so we concluded that the experimental compound may be able to bind to the same target. Molecular docking and atomic interaction studies with simvastatin and our experimental compound were compared. A pharmacophore modeling was done based on the experimental compound and HMG-CoA reductase inhibitor.Keywords: molecular docking, physicochemical properties, pharmacophore modeling structural similarity, pravastatin
Procedia PDF Downloads 3223654 The Exploration of the Physical Properties of the Combinations of Selenium-Based Ternary Chalcogenides AScSe₂ (A=K, Cs) for Photovoltaic Applications
Authors: Ayesha Asma, Aqsa Arooj
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It is an essential need in this era of Science and Technology to investigate some unique and appropriate materials for optoelectronic applications. Here, we deliberated, for the first time, the structural, optoelectronic, mechanical, vibrational, and thermo dynamical properties of hexagonal structure selenium-based ternary chalcogenides AScSe₂ (A= K, Cs) by using Perdew-Burke-Ernzerhof Generalized-Gradient-Approximation (PBE-GGA). The lattice angles for these materials are found as α=β=90o and γ=120o. KScSe₂ optimized with lattice parameters a=b=4.3 (Å), c=7.81 (Å) whereas CsScSe₂ got relaxed at a=b=4.43 (Å) and c=8.51 (Å). However, HSE06 functional has overestimated the lattice parameters to the extent that for KScSe₂ a=b=4.92 (Å), c=7.10 (Å), and CsScSe₂ a=b=5.15 (Å), c=7.09 (Å). The energy band gap of these materials calculated via PBE-GGA and HSE06 functionals confirms their semiconducting nature. Concerning Born’s criteria, these materials are mechanically stable ones. Moreover, the temperature dependence of thermodynamic potentials and specific heat at constant volume are also determined while using the harmonic approximation. The negative values of free energy ensure their thermodynamic stability. The vibrational modes are calculated by plotting the phonon dispersion and the vibrational density of states (VDOS), where infrared (IR) and Raman spectroscopy are used to characterize the vibrational modes. The various optical parameters are examined at a smearing value of 0.5eV. These parameters unveil that these materials are good absorbers of incident light in ultra-violet (UV) regions and may be utilized in photovoltaic applications.Keywords: structural, optimized, vibrational, ultraviolet
Procedia PDF Downloads 443653 Sustainable Development of Medium Strength Concrete Using Polypropylene as Aggregate Replacement
Authors: Reza Keihani, Ali Bahadori-Jahromi, Timothy James Clacy
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Plastic as an environmental burden is a well-rehearsed topic in the research area. This is due to its global demand and destructive impacts on the environment, which has been a significant concern to the governments. Typically, the use of plastic in the construction industry is seen across low-density, non-structural applications due to its diverse range of benefits including high strength-to-weight ratios, manipulability and durability. It can be said that with the level of plastic consumption experienced in the construction industry, an ongoing responsibility is shown for this sector to continually innovate alternatives for application of recycled plastic waste such as using plastic made replacement from polyethylene, polystyrene, polyvinyl and polypropylene in the concrete mix design. In this study, the impact of partially replaced fine aggregate with polypropylene in the concrete mix design was investigated to evaluate the concrete’s compressive strength by conducting an experimental work which comprises of six concrete mix batches with polypropylene replacements ranging from 0.5 to 3.0%. The results demonstrated a typical decline in the compressive strength with the addition of plastic aggregate, despite this reduction generally mitigated as the level of plastic in the concrete mix increased. Furthermore, two of the six plastic-containing concrete mixes tested in the current study exceeded the ST5 standardised prescribed concrete mix compressive strength requirement at 28-days containing 1.50% and 2.50% plastic aggregates, which demonstrated the potential for use of recycled polypropylene in structural applications, as a partial by mass, fine aggregate replacement in the concrete mix.Keywords: compressive strength, concrete, polypropylene, sustainability
Procedia PDF Downloads 1413652 Inappropriate Job Behaviour and Performance of Employees
Authors: Prakash Singh
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The focus of this paper is on the impact of internal organizational factors on the inappropriate job performance and behaviour of employees. The Buffalo City Metropolitan Municipality (BCMM) in South Africa has been experiencing inappropriate job behaviour and performance of some of its workers. They include misappropriation of resources, maladministration, mismanagement, lack of service delivery, fraud, and corruption. Since many workers in this organization have various levels of formal education, such practices are not expected, because the structural-functionalist assumption is that formal education is a solution to societal challenges. Since inappropriate job behaviour and performance continue to be reported in spite of the formal education of BCMM workers, this study seeks to investigate how the two phenomena co-exist. It thus seeks to put into perspective the paradoxical co-existence of formal education with inappropriate job behaviour and performance, by focusing on the BCMM as a case-study. For data collection, this study used the mixed method approach; that is, a combination of qualitative and quantitative methods. The findings revealed structural, systemic and human impediments to labour productivity in the organization. By and large, the unquestioning acceptance of the assumption that the skills shortage is responsible for inappropriate workers’ job performance and behaviour is discredited by the evidence of skilled personnel who exercise their responsibilities in a manner that undermines their occupational requirements. Therefore, this exploratory study affirms that the narrow conception of skills, that privileges job-specific capabilities, is not enough for cultivating a workforce with appropriate job behaviour and performance practices.Keywords: inappropriate job behaviour, labour productivity, mismanagement, skills shortage
Procedia PDF Downloads 3743651 Diversity Indices as a Tool for Evaluating Quality of Water Ways
Authors: Khadra Ahmed, Khaled Kheireldin
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In this paper, we present a pedestrian detection descriptor called Fused Structure and Texture (FST) features based on the combination of the local phase information with the texture features. Since the phase of the signal conveys more structural information than the magnitude, the phase congruency concept is used to capture the structural features. On the other hand, the Center-Symmetric Local Binary Pattern (CSLBP) approach is used to capture the texture information of the image. The dimension less quantity of the phase congruency and the robustness of the CSLBP operator on the flat images, as well as the blur and illumination changes, lead the proposed descriptor to be more robust and less sensitive to the light variations. The proposed descriptor can be formed by extracting the phase congruency and the CSLBP values of each pixel of the image with respect to its neighborhood. The histogram of the oriented phase and the histogram of the CSLBP values for the local regions in the image are computed and concatenated to construct the FST descriptor. Several experiments were conducted on INRIA and the low resolution DaimlerChrysler datasets to evaluate the detection performance of the pedestrian detection system that is based on the FST descriptor. A linear Support Vector Machine (SVM) is used to train the pedestrian classifier. These experiments showed that the proposed FST descriptor has better detection performance over a set of state of the art feature extraction methodologies.Keywords: planktons, diversity indices, water quality index, water ways
Procedia PDF Downloads 5203650 Properties and Antimicrobial Activity of Fish Protein Isolate/Fish Skin Gelatin Film Containing Basil Leaf Essential Oil and Zinc Oxide Nanoparticles
Authors: Yasir Ali Arfat
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Composite films based on fish protein isolate (FPI) and fish skin gelatin (FSG) blend incorporated with 50 and 100% (w/w, protein) basil leaf essential oil (BEO) in the absence and presence of 3% (w/w, protein) ZnO nanoparticles (ZnONP) were prepared and characterised. Tensile strength (TS) decreased, whilst elongation at break (EAB) increased as BEO level increased (p < 0.05). However, ZnONP addition resulted in higher TS but lower EAB (p < 0.05). The lowest water vapour permeability (WVP) was observed for the film incorporated with 100% BEO and 3% ZnONP (p < 0.05). BEO and ZnONP incorporation decreased transparency of FPI/FSG films (p < 0.05). FTIR spectra indicated that films added with BEO exhibited higher hydrophobicity. Both BEO and ZnONP had a marked impact on thermal stability of the films. Microstructural study revealed that presence of ZnONP prevented bilayer formation of film containing 100% BEO. FPI/FSG films incorporated with 100% BEO, especially in combination with ZnONP, exhibited strong antibacterial activity against food pathogenic and spoilage bacteria and thus could be used as an active food packaging material to ensure safety and to extend the shelf-life of packaged foods.Keywords: bionanocomposite, fish protein isolate, fish skin gelatin, basil essential oil, ZnO nanoparticles, antimicrobial packaging
Procedia PDF Downloads 4723649 Properties of Concrete with Wood Ashes in Construction Engineering
Authors: Piotr-Robert Lazik, Lena Teichmann, Harald Garrecht
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Many concrete technologists are looking for a solution to replace fly ashes as a component that occurs as a major component of many types of concrete. The importance of such a component is clear -it saves cement and reduces the amount of CO₂ in the atmosphere that occurs during cement production. For example, the amount of cement in ultrahigh strength concrete (UHPC) is approximately 700-800 kg/m³ in normal concrete up to 350 kg/m³. For this reason, it is easy to follow that the use of components like fly ashes or wood ashes protect the environment. The newest investigations carried out at the University of Stuttgart have clearly shown that the use of wood ashes with appropriate pre-treatment in concrete has a positive effect. German-wide, there are hundreds of tons of wood ashes, which can be used in a wide range of construction materials. The strengths of the concrete with different types of cement and with wood ashes have given the same or, in some cases, better results than those with the use of fly ashes. There are many areas in building construction, where the clays of wood ashes can be used as a by-product. This does not only require a strength test but also, for example, an examination of structural-physical parameters. Especially the heat and moisture characteristics have an important role in times of energy-efficient construction. These are therefore determined and then compared with the characteristics of the concretes with fly ashes. The University of Stuttgart has decided to investigate the buildings' physical properties of different types of concrete with wood ashes to find their application in construction. After the examination of the buildings' physical properties in combination with strength tests, it is possible to determine in which field of civil engineering, this type of concrete can be used.Keywords: fly ashes, wood ashes, structural-physical parameters, UHPC
Procedia PDF Downloads 1483648 Inherited Intergenerational Trauma – The Society for Black People in South Central Los Angeles
Authors: Kevin R. Collins Sr.
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In South Central Los Angeles, Black people have endured various forms of trauma that spans across generations. This includes the horrors of slavery and the aftermaths of the Jim Crow Laws, institutionalized racism, and legislative segregation, just to name a few. The individuals born from the 1900’s until today have continued to transmit the traumas experienced across generations. Parents unconsciously transmit the hidden trauma, and the children take these experiences and apply it to the society they live in. Although there are some who attempt to break the cycle of transmitted trauma, the remninsce still remain and play a huge role in how they interact with others. The attempt of this discussion is to bring these traumatic experiences to the surface and attack them head on. It is important that we do this to allow not only the suffering individuals but the suffering society to heal. As a society, looking at the humane side of it and attempting to stop the racial injustice placed on black people to relieve them of the stress that some. If not all,, endure in this great United States of America. Changing the behavior as a country to create an improved since of common unity within. If we solve our own racial and social issues within this country, maybe we can solve these same issues that have been the footstool to the many wars we see around the world. Thus, breaking the cycle of inherited intergenerational trauma.Keywords: intergenerational trauma, inherited trauma, transmission of trauma, blacks in South central LA, black trauma in America
Procedia PDF Downloads 1003647 Using Two-Mode Network to Access the Connections of Film Festivals
Authors: Qiankun Zhong
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In a global cultural context, film festival awards become authorities to define the aesthetic value of films. To study which genres and producing countries are valued by different film festivals and how those evaluations interact with each other, this research explored the interactions between the film festivals through their selection of movies and the factors that lead to the tendency of film festivals to nominate the same movies. To do this, the author employed a two-mode network on the movies that won the highest awards at five international film festivals with the highest attendance in the past ten years (the Venice Film Festival, the Cannes Film Festival, the Toronto International Film Festival, Sundance Film Festival, and the Berlin International Film Festival) and the film festivals that nominated those movies. The title, genre, producing country and language of 50 movies, and the range (regional, national or international) and organizing country or area of 129 film festivals were collected. These created networks connected by nominating the same films and awarding the same movies. The author then assessed the density and centrality of these networks to answer the question: What are the film festivals that tend to have more shared values with other festivals? Based on the Eigenvector centrality of the two-mode network, Palm Springs, Robert Festival, Toronto, Chicago, and San Sebastian are the festivals that tend to nominate commonly appreciated movies. In contrast, Black Movie Film Festival has the unique value of generally not sharing nominations with other film festivals. A homophily test was applied to access the clustering effects of film and film festivals. The result showed that movie genres (E-I index=0.55) and geographic location (E-I index=0.35) are possible indicators of film festival clustering. A blockmodel was also created to examine the structural roles of the film festivals and their meaning in real-world context. By analyzing the same blocks with film festival attributes, it was identified that film festivals either organized in the same area, with the same history, or with the same attitude on independent films would occupy the same structural roles in the network. Through the interpretation of the blocks, language was identified as an indicator that contributes to the role position of a film festival. Comparing the result of blockmodeling in the different periods, it is seen that international film festivals contrast with the Hollywood industry’s dominant value. The structural role dynamics provide evidence for a multi-value film festival network.Keywords: film festivals, film studies, media industry studies, network analysis
Procedia PDF Downloads 319