Search results for: labour force diversity
Commenced in January 2007
Frequency: Monthly
Edition: International
Paper Count: 4294

Search results for: labour force diversity

3094 The Social Origin Pay Gap in the UK Household Longitudinal Study

Authors: Michael Vallely

Abstract:

This paper uses data from waves 1 to 10 (2009-2019) of the UK Household Longitudinal Study to examine the social origin pay gap in the UK labour market. We find that regardless of how we proxy social origin, whether it be using the dominance approach, total parental occupation, parental education, total parental education, or the higher parental occupation and higher parental education, the results have one thing in common; in all cases, we observe a significant social origin pay gap for those from the lower social origins with the largest pay gap observed for those from the ‘lowest’ social origin. The results may indicate that when we consider the occupational status and education of both parents, previous estimates of social origin pay gaps and the number of individuals affected may have been underestimated. We also observe social origin pay gaps within educational attainment groups, such as degree holders, and within professional and managerial occupations. Therefore, this paper makes a valuable contribution to the social origin pay gap literature as it provides empirical evidence of a social origin pay gap using a large-scale UK dataset and challenges the argument that education is the great ‘social leveller’.

Keywords: social class, social origin, pay gaps, wage inequality

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3093 The Effect of Mechanical Stress on the Magnetic Structure and Properties of Ferromagnetic Microwires in Glass Insulation

Authors: N. N. Orlova, A. S. Aronin, Yu. P. Kabanov, S. I. Bozhko, V. S. Gornakov

Abstract:

We have investigated the change of the magnetic structure and the hysteresis properties of iron-based microwires after decreasing levels of internal mechanical stresses. The magnetic structure was investigated by the method of magneto-optical indicator film and the method of magnetic force microscopy. The hysteresis properties were studied by the vibrating sample magnetometer. The stresses were decreased by removing the glass coat and/or by low-temperature isothermal annealing. Previously, the authors carried out experimentally investigation of the magnetic structure of Fe-based microwire using these methods. According to the obtained results the domain structure of a microwire with a positive magnetostriction is composed of the inner cylindrical domains with the magnetization along the wire axis and the surface layer of the ring shape domains with the radial direction of magnetization. Surface ring domains with opposite magnetization direction (i.e., to the axis or from the axis) alternate with each other. For the first time the size of magnetic domains was determined experimentally. In this study it was found that in the iron-based microwires the value of the coercive force can be reduce more than twice by decreasing levels of internal mechanical stresses. Decrease of the internal stress value by the relaxation annealing influence on the magnetic structure. So in the as-prepared microwires observed local deviations of the magnetization of the magnetic core domains from the axis of the wire. After low-temperature annealing the local deviations of magnetization is not observed.

Keywords: amorphous microwire, magnetic structure, internal stress, hysteresis properties, ferromagnetic

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3092 Mechanical Behavior of Sandwiches with Various Glass Fiber/Epoxy Skins under Bending Load

Authors: Emre Kara, Metehan Demir, Şura Karakuzu, Kadir Koç, Ahmet F. Geylan, Halil Aykul

Abstract:

While the polymeric foam cored sandwiches have been realized for many years, recently there is a growing and outstanding interest on the use of sandwiches consisting of aluminum foam core because of their some of the distinct mechanical properties such as high bending stiffness, high load carrying and energy absorption capacities. These properties make them very useful in the transportation industry (automotive, aerospace, shipbuilding industry), where the "lightweight design" philosophy and the safety of vehicles are very important aspects. Therefore, in this study, the sandwich panels with aluminum alloy foam core and various types and thicknesses of glass fiber reinforced polymer (GFRP) skins produced via Vacuum Assisted Resin Transfer Molding (VARTM) technique were obtained by using a commercial toughened epoxy based adhesive with two components. The aim of this contribution was the analysis of the bending response of sandwiches with various glass fiber reinforced polymer skins. The three point bending tests were performed on sandwich panels at different values of support span distance using a universal static testing machine in order to clarify the effects of the type and thickness of the GFRP skins in terms of peak load, energy efficiency and absorbed energy values. The GFRP skins were easily bonded to the aluminum alloy foam core under press machine with a very low pressure. The main results of the bending tests are: force-displacement curves, peak force values, absorbed energy, collapse mechanisms and the influence of the support span length and GFRP skins. The obtained results of the experimental investigation presented that the sandwich with the skin made of thicker S-Glass fabric failed at the highest load and absorbed the highest amount of energy compared to the other sandwich specimens. The increment of the support span distance made the decrease of the peak force and absorbed energy values for each type of panels. The common collapse mechanism of the panels was obtained as core shear failure which was not affected by the skin materials and the support span distance.

Keywords: aluminum foam, collapse mechanisms, light-weight structures, transport application

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3091 Latinx Adult ELLs: Exploring English Instructors’ Perceptions of Classroom Diversity and Culturally Diverse Teaching Strategies

Authors: Sharon Diaz Ruiz

Abstract:

This qualitative study addresses college English instructors’ perceptions of classroom diversity and culturally diverse teaching strategies within the adult English language learning classroom environment. Every year, English college instructors face numerous challenges as the adult Latinx population keeps rising. To better understand the Latinx adult learners and the language classroom dynamics, research should focus on the experiences, pedagogical methods, and teaching insights of full-time and adjunct minority professors at degree-granting postsecondary institutions. Culturally responsive teaching is used as the framework to understand and explore the perceptions of English instructors on the realities and needs of Latinx adult emergent bilinguals enrolled in developmental English courses. Snowball sampling allows the researcher to locate members who meet these specific criteria: adjunct and part-time English instructors of adult Latinx language learners. Participants answered a demographic questionnaire and then contributed to 45-minute in-depth interviews to explore their perceptions of culturally responsive practices in the Latinx adult emergent bilinguals’ basic and intermediate developmental English courses. The interviews shed light on topics such as teaching biases, educators’ cultural experiences, and resources and strategies faculty recommend for effective culturally responsive teaching strategies. The result of this investigation will shed light on the gap in the literature documenting the application of culturally responsive pedagogy to Latino adult language learners.

Keywords: Latinx, English language learners, English faculty, adult learners, critical theory, culturally responsive theory

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3090 A Study on Soil Micro-Arthropods Assemblage in Selected Plantations in The Nilgiris, Tamilnadu

Authors: J. Dharmaraj, C. Gunasekaran

Abstract:

Invertebrates are the reliable ecological indicators of disturbance of the forest ecosystems and they respond to environment changes more quickly than other fauna. Among these the terrestrial invertebrates are vital to functioning ecosystems, contributing to processes such as decomposition, nutrient cycling and soil fertility. The natural ecosystems of the forests have been subject to various types of disturbances, which lead to decline of flora and fauna. The comparative diversity of micro-arthropods in natural forest, wattle plantation and eucalyptus plantations were studied in Nilgiris. The study area was divided in to five major sites (Emerald (Site-I), Thalaikundha (Site-II), Kodapmund (Site-III), Aravankad (Site-IV), Kattabettu (Site-V). The research was conducted during period from March 2014 to August 2014. The leaf and soil samples were collected and isolated by using Berlese funnel extraction methods. Specimens were isolated and identified according to their morphology (Balogh 1972). In the present study results clearly showed the variation in soil pH, NPK (Major Nutrients) and organic carbon among the study sites. The chemical components of the leaf litters of the plantation decreased the diversity of micro-arthropods and decomposition rate leads to low amount of carbon and other nutrients present in the soil. Moreover eucalyptus and wattle plantations decreases the availability of the ground water source to other plantations and micro-arthropods and hences affects the soil fertility. Hence, the present study suggests to minimize the growth of wattle and eucalyptus tree plantations in the natural areas which may help to reduce the decline of forests.

Keywords: micro-arthropods, assemblage, berlese funnel, morphology, NPK, nilgiris

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3089 Toehold Mediated Shape Transition of Nucleic Acid Nanoparticles

Authors: Emil F. Khisamutdinov

Abstract:

Development of functional materials undergoing structural transformations in response to an external stimulus such as environmental changes (pH, temperature, etc.), the presence of particular proteins, or short oligonucleotides are of great interest for a variety of applications ranging from medicine to electronics. The dynamic operations of most nucleic acid (NA) devices, including circuits, nano-machines, and biosensors, rely on networks of NA strand displacement processes in which an external or stimulus strand displaces a target strand from a DNA or RNA duplex. The rate of strand displacement can be greatly increased by the use of “toeholds,” single-stranded regions of the target complex to which the invading strand can bind to initiate the reaction, forming additional base pairs that provide a thermodynamic driving force for transformation. Herein, we developed a highly robust nanoparticle shape transition, sequentially transforming DNA polygons from one shape to another using the toehold-mediated DNA strand displacement technique. The shape transformation was confirmed by agarose gel electrophoresis and atomic force microscopy. Furthermore, we demonstrate that our approach is applicable for RNA shape transformation from triangle to square, which can be detected by fluorescence emission from malachite green binding RNA aptamer. Using gel-shift and fluorescence assays, we demonstrated efficient transformation occurs at isothermal conditions (37°C) that can be implemented within living cells as reporter molecules. This work is intended to provide a simple, cost-effective, and straightforward model for the development of biosensors and regulatory devices in nucleic acid nanotechnology.

Keywords: RNA nanotechnology, bionanotechnology, toehold mediated DNA switch, RNA split fluorogenic aptamers

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3088 Contribution of Upper Body Kinematics on Tennis Serve Performance

Authors: Ikram Hussain, Fuzail Ahmad, Tawseef Ahmad Bhat

Abstract:

Tennis serve is characterized as one of the most prominent techniques pertaining to the success of winning a point. The study was aimed to explore the contributions of the upper body kinematics on the tennis performance during Davis Cup (Oceania Group). Four Indian International tennis players who participated in the Davis Cup held at Indore, India were inducted as the subjects for this study, with mean age 27 ± 4.79 Years, mean weight 186 ± 6.03 cm, mean weight 81.25 ± 7.41kg, respectively. The tennis serve was bifurcated into three phases viz, preparatory phase, force generation phase and follow through phase. The kinematic data for the study was recorded through the high speed canon camcorder having a shuttle speed of 1/2000, at a frame rate of 50 Hz. The data was analysed with the motion analysis software. The descriptive statistics and F-test was employed through SPSS version 17.0 for the determination of the undertaken kinematic parameters of the study, and was computed at a 0.05 level of significance with 46 degrees of freedom. Mean, standard deviation and correlation coefficient also employed to find out the relationship among the upper body kinematic parameter and performance. In the preparatory phase, the analysis revealed that no significant difference exists among the kinematic parameters of the players on the performance. However, in force generation phase, wrist velocity (r= 0.47), torso velocity (r= -0.53), racket velocity r= 0.60), and in follow through phase, torso acceleration r= 0.43), elbow angle (r= -0.48) play a significant role on the performance of the tennis serve. Therefore, players should ponder upon the velocities of the above segments at the time of preparation for the competitions.

Keywords: Davis Cup, kinematics, motion analysis, tennis serve

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3087 Design and Manufacture of a Hybrid Gearbox Reducer System

Authors: Ahmed Mozamel, Kemal Yildizli

Abstract:

Due to mechanical energy losses and a competitive of minimizing these losses and increases the machine efficiency, the need for contactless gearing system has raised. In this work, one stage of mechanical planetary gear transmission system integrated with one stage of magnetic planetary gear system is designed as a two-stage hybrid gearbox system. The permanent magnets internal energy in the form of the magnetic field is used to create meshing between contactless magnetic rotors in order to provide self-system protection against overloading and decrease the mechanical loss of the transmission system by eliminating the friction losses. Classical methods, such as analytical, tabular method and the theory of elasticity are used to calculate the planetary gear design parameters. The finite element method (ANSYS Maxwell) is used to predict the behaviors of a magnetic gearing system. The concentric magnetic gearing system has been modeled and analyzed by using 2D finite element method (ANSYS Maxwell). In addition to that, design and manufacturing processes of prototype components (a planetary gear, concentric magnetic gear, shafts and the bearings selection) of a gearbox system are investigated. The output force, the output moment, the output power and efficiency of the hybrid gearbox system are experimentally evaluated. The viability of applying a magnetic force to transmit mechanical power through a non-contact gearing system is presented. The experimental test results show that the system is capable to operate continuously within the range of speed from 400 rpm to 3000 rpm with the reduction ratio of 2:1 and maximum efficiency of 91%.

Keywords: hybrid gearbox, mechanical gearboxes, magnetic gears, magnetic torque

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3086 Virtual Computing Lab for Phonics Development among Deaf Students

Authors: Ankita R. Bansal, Naren S. Burade

Abstract:

Idea is to create a cloud based virtual lab for Deaf Students, “A language acquisition program using Visual Phonics and Cued Speech” using VMware Virtual Lab. This lab will demonstrate students the sounds of letters associated with the Language, building letter blocks, making words, etc Virtual labs are used for demos, training, for the Lingual development of children in their vernacular language. The main potential benefits are reduced labour and hardware costs, faster response times to users. Virtual Computing Labs allows any of the software as a service solutions, virtualization solutions, and terminal services solutions available today to offer as a service on demand, where a single instance of the software runs on the cloud and services multiple end users. VMWare, XEN, MS Virtual Server, Virtuoso, and Citrix are typical examples.

Keywords: visual phonics, language acquisition, vernacular language, cued speech, virtual lab

Procedia PDF Downloads 589
3085 The Effects of Above-Average Precipitation after Extended Drought on Phytoplankton in Southern California Surface Water Reservoirs

Authors: Margaret K. Spoo-Chupka

Abstract:

The Metropolitan Water District of Southern California (MWDSC) manages surface water reservoirs that are a source of drinking water for more than 19 million people in Southern California. These reservoirs experience periodic planktonic cyanobacteria blooms that can impact water quality. MWDSC imports water from two sources – the Colorado River (CR) and the State Water Project (SWP). The SWP brings supplies from the Sacramento-San Joaquin Delta that are characterized as having higher nutrients than CR water. Above average precipitation in 2017 after five years of drought allowed the majority of the reservoirs to fill. Phytoplankton was analyzed during the drought and after the drought at three reservoirs: Diamond Valley Lake (DVL), which receives SWP water exclusively, Lake Skinner, which can receive a blend of SWP and CR water, and Lake Mathews, which generally receives only CR water. DVL experienced a significant increase in water elevation in 2017 due to large SWP inflows, and there were no significant changes to total phytoplankton biomass, Shannon-Wiener diversity of the phytoplankton, or cyanobacteria biomass in 2017 compared to previous drought years despite the higher nutrient loads. The biomass of cyanobacteria that could potentially impact DVL water quality (Microcystis spp., Aphanizomenon flos-aquae, Dolichospermum spp., and Limnoraphis birgei) did not differ significantly between the heavy precipitation year and drought years. Compared to the other reservoirs, DVL generally has the highest concentration of cyanobacteria due to the water supply having greater nutrients. Lake Mathews’ water levels were similar in drought and wet years due to a reliable supply of CR water and there were no significant changes in the total phytoplankton biomass, phytoplankton diversity, or cyanobacteria biomass in 2017 compared to previous drought years. The biomass of cyanobacteria that could potentially impact water quality at Lake Mathews (L. birgei and Microcystis spp.) did not differ significantly between 2017 and previous drought years. Lake Mathews generally had the lowest cyanobacteria biomass due to the water supply having lower nutrients. The CR supplied most of the water to Lake Skinner during drought years, while the SWP was the primary source during 2017. This change in water source resulted in a significant increase in phytoplankton biomass in 2017, no significant change in diversity, and a significant increase in cyanobacteria biomass. Cyanobacteria that could potentially impact water quality at Skinner included: Microcystis spp., Dolichospermum spp., and A.flos-aquae. There was no significant difference in Microcystis spp. biomass in 2017 compared to previous drought years, but biomass of Dolichospermum spp. and A.flos-aquae were significantly greater in 2017 compared to previous drought years. Dolichospermum sp. and A. flos-aquae are two cyanobacteria that are more sensitive to nutrients than Microcystis spp., which are more sensitive to temperature. Patterns in problem cyanobacteria abundance among Southern California reservoirs as a result of above-average precipitation after more than five years of drought were most closely related to nutrient loading.

Keywords: drought, reservoirs, cyanobacteria, and phytoplankton ecology

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3084 Multidimensional Modeling of Solidification Process of Multi-Crystalline Silicon under Magnetic Field for Solar Cell Technology

Authors: Mouhamadou Diop, Mohamed I. Hassan

Abstract:

Molten metallic flow in metallurgical plant is highly turbulent and presents a complex coupling with heat transfer, phase transfer, chemical reaction, momentum transport, etc. Molten silicon flow has significant effect in directional solidification of multicrystalline silicon by affecting the temperature field and the emerging crystallization interface as well as the transport of species and impurities during casting process. Owing to the complexity and limits of reliable measuring techniques, computational models of fluid flow are useful tools to study and quantify these problems. The overall objective of this study is to investigate the potential of a traveling magnetic field for an efficient operating control of the molten metal flow. A multidimensional numerical model will be developed for the calculations of Lorentz force, molten metal flow, and the related phenomenon. The numerical model is implemented in a laboratory-scale silicon crystallization furnace. This study presents the potential of traveling magnetic field approach for an efficient operating control of the molten flow. A numerical model will be used to study the effects of magnetic force applied on the molten flow, and their interdependencies. In this paper, coupled and decoupled, steady and unsteady models of molten flow and crystallization interface will be compared. This study will allow us to retrieve the optimal traveling magnetic field parameter range for crystallization furnaces and the optimal numerical simulations strategy for industrial application.

Keywords: multidimensional, numerical simulation, solidification, multicrystalline, traveling magnetic field

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3083 Labor Migration: An Anthropological Study of Migrants Socio-Economic Development and Exploitation

Authors: Usman Khan

Abstract:

The article discusses mass migration, which has been a problem throughout history. People moved for a variety of reasons, including better job opportunities, prosperous, healthy lifestyles, and other basic needs. This research focuses on the issues and challenges that immigrants face when they arrive at their destination countries especially Saudi Arab. Among these issues are the Kapala system, irregular salaries, living conditions, document seizure, and so on. The primary data sources for this qualitative anthropological study include in-depth interviews and focus group discussions (FGDs). The research was carried out in the villages of Zulam and Shagokas in Khyber Pakhtunkhwa's Dir Lower District. The article concludes by stating that the agents and employers treated labor migrants/workers inhumanely. Throughout the process, they have been subjected to severe exploitation and suffering. Finally, the migrants sent back remittances that aided the region's economic and infrastructure development.

Keywords: Migration, Exploitation, labour, Middle East, Kafala and Tanazol System.

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3082 Challenges of Landscape Design with Tree Species Diversity

Authors: Henry Kuppen

Abstract:

In the last decade, tree managers have faced many threats of pests and diseases and the effects of climate change. Managers will recognize that they have to put more energy and more money into tree management. By recognizing the cause behind this, the opportunity will arise to build sustainable tree populations for the future. More and more, unwanted larvae are sprayed, ash dieback infected trees are pruned or felled, and emerald ash borer is knocking at the door of West Europe. A lot of specific knowledge is needed to produce management plans and best practices. If pest and disease have a large impact, society loses complete tree species and need to start all over again building urban forest. But looking at the cause behind it, landscape design, and tree species selection, the sustainable solution does not present itself in managing these threats. Every pest or disease needs two important basic ingredients to be successful: climate and food. The changing climate is helping several invasive pathogens to survive. Food is often designed by the landscapers and managers of the urban forest. Monocultures promote the success of pathogens. By looking more closely at the basics, tree managers will realise very soon that the solution will not be the management of pathogens. The long-term solution for sustainable tree populations is a different design of our urban landscape. The use of tree species diversity can help to reduce the impact of climate change and pathogens. Therefore landscapers need to be supported. They are the specialists in designing the landscape using design values like canopy volume, ecosystem services, and seasonal experience. It’s up to the species specialist to show what the opportunities are for different species that meet the desired interpretation of the landscape. Based on landscapers' criteria, selections can be made, including tree species related requirements. Through this collaboration and formation of integral teams, sustainable plant design will be possible.

Keywords: climate change, landscape design, resilient landscape, tree species selection

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3081 Legal Considerations in Fashion Modeling: Protecting Models' Rights and Ensuring Ethical Practices

Authors: Fatemeh Noori

Abstract:

The fashion industry is a dynamic and ever-evolving realm that continuously shapes societal perceptions of beauty and style. Within this industry, fashion modeling plays a crucial role, acting as the visual representation of brands and designers. However, behind the glamorous façade lies a complex web of legal considerations that govern the rights, responsibilities, and ethical practices within the field. This paper aims to explore the legal landscape surrounding fashion modeling, shedding light on key issues such as contract law, intellectual property, labor rights, and the increasing importance of ethical considerations in the industry. Fashion modeling involves the collaboration of various stakeholders, including models, designers, agencies, and photographers. To ensure a fair and transparent working environment, it is imperative to establish a comprehensive legal framework that addresses the rights and obligations of each party involved. One of the primary legal considerations in fashion modeling is the contractual relationship between models and agencies. Contracts define the terms of engagement, including payment, working conditions, and the scope of services. This section will delve into the essential elements of modeling contracts, the negotiation process, and the importance of clarity to avoid disputes. Models are not just individuals showcasing clothing; they are integral to the creation and dissemination of artistic and commercial content. Intellectual property rights, including image rights and the use of a model's likeness, are critical aspects of the legal landscape. This section will explore the protection of models' image rights, the use of their likeness in advertising, and the potential for unauthorized use. Models, like any other professionals, are entitled to fair and ethical treatment. This section will address issues such as working conditions, hours, and the responsibility of agencies and designers to prioritize the well-being of models. Additionally, it will explore the global movement toward inclusivity, diversity, and the promotion of positive body image within the industry. The fashion industry has faced scrutiny for perpetuating harmful standards of beauty and fostering a culture of exploitation. This section will discuss the ethical responsibilities of all stakeholders, including the promotion of diversity, the prevention of exploitation, and the role of models as influencers for positive change. In conclusion, the legal considerations in fashion modeling are multifaceted, requiring a comprehensive approach to protect the rights of models and ensure ethical practices within the industry. By understanding and addressing these legal aspects, the fashion industry can create a more transparent, fair, and inclusive environment for all stakeholders involved in the art of modeling.

Keywords: fashion modeling contracts, image rights in modeling, labor rights for models, ethical practices in fashion, diversity and inclusivity in modeling

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3080 Optimization of Springback Prediction in U-Channel Process Using Response Surface Methodology

Authors: Muhamad Sani Buang, Shahrul Azam Abdullah, Juri Saedon

Abstract:

There is not much effective guideline on development of design parameters selection on springback for advanced high strength steel sheet metal in U-channel process during cold forming process. This paper presents the development of predictive model for springback in U-channel process on advanced high strength steel sheet employing Response Surface Methodology (RSM). The experimental was performed on dual phase steel sheet, DP590 in U-channel forming process while design of experiment (DoE) approach was used to investigates the effects of four factors namely blank holder force (BHF), clearance (C) and punch travel (Tp) and rolling direction (R) were used as input parameters using two level values by applying Full Factorial design (24). From a statistical analysis of variant (ANOVA), result showed that blank holder force (BHF), clearance (C) and punch travel (Tp) displayed significant effect on springback of flange angle (β2) and wall opening angle (β1), while rolling direction (R) factor is insignificant. The significant parameters are optimized in order to reduce the springback behavior using Central Composite Design (CCD) in RSM and the optimum parameters were determined. A regression model for springback was developed. The effect of individual parameters and their response was also evaluated. The results obtained from optimum model are in agreement with the experimental values

Keywords: advance high strength steel, u-channel process, springback, design of experiment, optimization, response surface methodology (rsm)

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3079 Using VR as a Training Tool in the Banking Industry

Authors: Bjørn Salskov, Nicolaj Bang, Charlotte Falko

Abstract:

Future labour markets demand employees that can carry out a non-linear task which is still not possible for computers. This means that employees must have well-developed soft-skills to perform at high levels in such a work environment. One of these soft-skills is presenting a message effectively. To be able to present a message effectively, one needs to practice this. To practice effectively, the trainee needs feedback on the current performance. Here VR environments can be used as a practice tool because it gives the trainee a sense of presence and reality. VR environments are becoming a cost-effective training method since it does not demand the presence of an expert to provide this feedback. The research article analysed in this study suggests that VR environment can be used and are able to provide the necessary feedback to the trainee which in turn will help the trainee become better at the task. The research analysed in this review does, however, show that there is a need for a study with larger sample size and a study which runs over a longer period.

Keywords: training, presentation, presentation skills, VR training, VR as a training tool, VR and presentation

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3078 Design of a Satellite Solar Panel Deployment Mechanism Using the Brushed DC Motor as Rotational Speed Damper

Authors: Hossein Ramezani Ali-Akbari

Abstract:

This paper presents an innovative method to control the rotational speed of a satellite solar panel during its deployment phase. A brushed DC motor has been utilized in the passive spring driven deployment mechanism to reduce the deployment speed. In order to use the DC motor as a damper, its connector terminals have been connected with an external resistance in a closed circuit. It means that, in this approach, there is no external power supply in the circuit. The working principle of this method is based on the back electromotive force (or back EMF) of the DC motor when an external torque (here the torque produced by the torsional springs) is coupled to the DC motor’s shaft. In fact, the DC motor converts to an electric generator and the current flows into the circuit and then produces the back EMF. Based on Lenz’s law, the generated current produced a torque which acts opposite to the applied external torque, and as a result, the deployment speed of the solar panel decreases. The main advantage of this method is to set an intended damping coefficient to the system via changing the external resistance. To produce the sufficient current, a gearbox has been assembled to the DC motor which magnifies the number of turns experienced by the DC motor. The coupled electro-mechanical equations of the system have been derived and solved, then, the obtained results have been presented. A full-scale prototype of the deployment mechanism has been built and tested. The potential application of brushed DC motors as a rotational speed damper has been successfully demonstrated.

Keywords: back electromotive force, brushed DC motor, rotational speed damper, satellite solar panel deployment mechanism

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3077 Trial of Faecal Microbial Transplantation for the Prevention of Canine Atopic Dermatitis

Authors: Caroline F. Moeser

Abstract:

The skin-gut axis defines the relationship between the intestinal microbiota and the development of pathological skin diseases. Low diversity within the gut can predispose to the development of allergic skin conditions, and a greater diversity of the gastrointestinal microflora has been associated with a reduction of skin flares in people with atopic dermatitis. Manipulation of the gut microflora has been used as a treatment option for several conditions in people, but there is limited data available on the use of faecal transplantation as a preventative measure in either people or dogs. Six, 4-month-old pups from a litter of ten were presented for diarrhea and/or signs of skin disease (chronic scratching, otitis externa). Of these pups, two were given probiotics with a resultant resolution of diarrhea. The other four pups were given faecal transplantation, either as a sole treatment or in combination with other treatments. Follow-up on the litter of ten pups was performed at 18 months of age. At this stage, the four pups that had received faecal transplantation had resolved all clinical signs and had no recurrence of either skin or gastrointestinal symptoms. Of the remaining six pups from the litter, all had developed at least one episode of Malassezia otitis externa within the period of 5 months to 18 months of age. Two pups had developed two Malassezia otitis infections, and one had developed three Malassezia otitis infections during this period. Favrot’s criteria for the diagnosis of canine atopic dermatitis include chronic or recurrent Malassezia infections by the age of three years. Early results from this litter predict a reduction in the development of canine atopic disease in dogs given faecal microbial transplantation. Follow-up studies at three years of age and within a larger population of dogs can enhance understanding of the impact of early faecal transplantation in the prevention of canine atopic dermatitis.

Keywords: canine atopic dermatitis, faecal microbial transplant, skin-gut axis, otitis

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3076 Orthogonal Metal Cutting Simulation of Steel AISI 1045 via Smoothed Particle Hydrodynamic Method

Authors: Seyed Hamed Hashemi Sohi, Gerald Jo Denoga

Abstract:

Machining or metal cutting is one of the most widely used production processes in industry. The quality of the process and the resulting machined product depends on parameters like tool geometry, material, and cutting conditions. However, the relationships of these parameters to the cutting process are often based mostly on empirical knowledge. In this study, computer modeling and simulation using LS-DYNA software and a Smoothed Particle Hydrodynamic (SPH) methodology, was performed on the orthogonal metal cutting process to analyze three-dimensional deformation of AISI 1045 medium carbon steel during machining. The simulation was performed using the following constitutive models: the Power Law model, the Johnson-Cook model, and the Zerilli-Armstrong models (Z-A). The outcomes were compared against the simulated results obtained by Cenk Kiliçaslan using the Finite Element Method (FEM) and the empirical results of Jaspers and Filice. The analysis shows that the SPH method combined with the Zerilli-Armstrong constitutive model is a viable alternative to simulating the metal cutting process. The tangential force was overestimated by 7%, and the normal force was underestimated by 16% when compared with empirical values. The simulation values for flow stress versus strain at various temperatures were also validated against empirical values. The SPH method using the Z-A model has also proven to be robust against issues of time-scaling. Experimental work was also done to investigate the effects of friction, rake angle and tool tip radius on the simulation.

Keywords: metal cutting, smoothed particle hydrodynamics, constitutive models, experimental, cutting forces analyses

Procedia PDF Downloads 250
3075 Exploring SL Writing and SL Sensitivity during Writing Tasks: Poor and Advanced Writing in a Context of Second Language other than English

Authors: Sandra Figueiredo, Margarida Alves Martins, Carlos Silva, Cristina Simões

Abstract:

This study integrates a larger research empirical project that examines second language (SL) learners’ profiles and valid procedures to perform complete and diagnostic assessment in schools. 102 learners of Portuguese as a SL aged 7 and 17 years speakers of distinct home languages were assessed in several linguistic tasks. In this article, we focused on writing performance in the specific task of narrative essay composition. The written outputs were measured using the score in six components adapted from an English SL assessment context (Alberta Education): linguistic vocabulary, grammar, syntax, strategy, socio-linguistic, and discourse. The writing processes and strategies in Portuguese language used by different immigrant students were analysed to determine features and diversity of deficits on authentic texts performed by SL writers. Differentiated performance was based on the diversity of the following variables: grades, previous schooling, home language, instruction in first language, and exposure to Portuguese as Second Language. Indo-Aryan languages speakers showed low writing scores compared to their peers and the type of language and respective cognitive mapping (such as Mandarin and Arabic) was the predictor, not linguistic distance. Home language instruction should also be prominently considered in further research to understand specificities of cognitive academic profile in a Romance languages learning context. Additionally, this study also examined the teachers representations that will be here addressed to understand educational implications of second language teaching in psychological distress of different minorities in schools of specific host countries.

Keywords: home language, immigrant students, Portuguese language, second language, writing assessment

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3074 Values-based Physical Education in a Diverse South African Context

Authors: C. F. Jones Couto

Abstract:

The implementation of quality Physical Education (PE) inspires and instils lasting healthy behavioural patterns, hence have the potential as an educational tool to teach values in today’s society. The goal of PE should be to contribute to the acceptance of the infinite qualities of South Africa’s (RSA) diversity and to claim RSA’s diversity as a source of strength that forms a universal bond of a common set of values. There is a global change in the interaction of children with their environment; their lives are shaped by forces that do not necessarily assist them in learning and applying values. In most countries today, the responsibility for developing values is assigned to schools in formal teaching settings. Values-based education offers an investment in individual and societal improvement through attendance to a values framework. The aim of this qualitative research is to develop a PE programme aligned with the current South African curriculum, enriched with values of Olympism and Ubuntuism, and to present PE teacher training workshops (TTW). Participatory action research will be used as the basis of how data will be collected, analysed, and presented on an ongoing, cyclical basis. PE teachers from different schools in the Tshwane District of RSA will participate as they can best inform the research questions and enhance the understanding of the phenomenon under study. The outcomes of using PE as a tool to teach values can propose recommendations to the Department of Basic Education of RSA to improve and implement a quality PE curriculum that is applicable to practice and that will optimize the chances of meeting the South African National Curriculum Statement standards. A PE programme with the aim of holistic development, based on the values of Olympism and Ubuntuism, can strive to ensure that the values set out in RSA’s constitution are part of PE organization, planning, and teaching at each South African school.

Keywords: olympism, physical education, teacher training, ubuntuism, values-based education

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3073 Developing Pan-University Collaborative Initiatives in Support of Diversity and Inclusive Campuses

Authors: David Philpott, Karen Kennedy

Abstract:

In recognition of an increasingly diverse student population, a Teaching and Learning Framework was developed at Memorial University of Newfoundland. This framework emphasizes work that is engaging, supportive, inclusive, responsive, committed to discovery, and is outcomes-oriented for both educators and learners. The goal of the Teaching and Learning framework was to develop a number of initiatives that builds on existing knowledge, proven programs, and existing supports in order to respond to the specific needs of identified groups of diverse learners: 1) academically vulnerable first year students; 2) students with individual learning needs associated with disorders and/or mental health issues; 3) international students and those from non-western cultures. This session provides an overview of this process. The strategies employed to develop these initiatives were drawn primarily from research on student success and retention (literature review), information on pre-existing programs (environmental scan), an analysis of in-house data on students at our institution; consultations with key informants at all of Memorial’s campuses. The first initiative that emerged from this research was a pilot project proposal for a first-year success program in support of the first-year experience of academically vulnerable students. This program offers a university experience that is enhanced by smaller classes, supplemental instruction, learning communities, and advising sessions. The second initiative that arose under the mandate of the Teaching and Learning Framework was a collaborative effort between two institutions (Memorial University and the College of the North Atlantic). Both institutions participated in a shared conversation to examine programs and services that support an accessible and inclusive environment for students with disorders and/or mental health issues. A report was prepared based on these conversations and an extensive review of research and programs across the country. Efforts are now being made to explore possible initiatives that address culturally diverse and non-traditional learners. While an expanding literature has emerged on diversity in higher education, the process of developing institutional initiatives is usually excluded from such discussions, while the focus remains on effective practice. The proposals that were developed constitute a co-ordination and strengthening of existing services and programs; a weaving of supports to engage a diverse body of students in a sense of community. This presentation will act as a guide through the process of developing projects addressing learner diversity and engage attendees in a discussion of institutional practices that have been implemented in support of overcoming challenges, as well as provide feedback on institutional and student outcomes. The focus of this session will be on effective practice, and will be of particular interest to university administrators, educational developers, and educators wishing to implement similar initiatives on their campuses; possible adaptations for practice will be addressed. A presentation of findings from this research will be followed by an open discussion where the sharing of research, initiatives, and best practices for the enhancement of teaching and learning is welcomed. There is much insight and understanding to be gained through the sharing of ideas and collaborative practice as we move forward to further develop the program and prepare other initiatives in support of diversity and inclusion.

Keywords: eco-scale, green analysis, environmentally-friendly, pharmaceuticals analysis

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3072 Effect of Species and Slaughtering Age on Quality Characteristics of Different Meat Cuts of Humped Cattle and Water Buffalo Bulls

Authors: Muhammad Kashif Yar, Muhammad Hayat Jaspal, Muawuz Ijaz, Zafar Hayat, Iftikhar Hussain Badar, Jamal Nasir

Abstract:

Meat quality characteristics such as ultimate pH (pHu), color, cooking loss and shear force of eight wholesale meat cuts of humped cattle (Bos indicus) and water buffalo (Bubalus bubalis) bulls at two age groups were evaluated. A total of 48 animals, 24 of each species and within species 12 from each 18 and 26 months age group were slaughtered. After 24h post-slaughter, eight meat cuts, i.e., tenderloin, sirloin, rump, cube roll, round, topside, silverside and blade were cut from the carcass. The pHu of tenderloin (5.65 vs 5.55), sirloin (5.67 vs 5.60), cube roll (5.68 vs 5.62) and blade (5.88 vs 5.72) was significantly higher (P<0.05) in buffalo than cattle. The tenderloin showed significantly higher (44.63 vs 42.23) and sirloin showed lower (P<0.05) mean L* value (42.28 vs 44.47) in cattle than buffalo whilst the mean L* value of the only tenderloin was affected by animal age. Species had a significant (P<0.05) effect on mean a*, b*, C, and h values of all meat cuts. The shear force of the majority of meat cuts, within species and age groups, varied considerably. The mean shear values of tenderloin, sirloin, cube roll and blade were higher (P<0.05) in buffalo than cattle. The shear values of rump, round, topside and silverside increased significantly (P<0.05) with animal age. In conclusion, primal cuts of cattle showed better meat quality especially tenderness than buffalo. Furthermore, calves should be raised at least up to 26 months of age to maximize profitability by providing better quality meat.

Keywords: buffalo, cattle, meat color, meat quality, slaughtering age, tenderness

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3071 Effect of Fiddler Crab Burrows on Bacterial Communities of Mangrove Sediments

Authors: Mohammad Mokhtari, Gires Usup, Zaidi Che Cob

Abstract:

Bacteria communities as mediators of the biogeochemical process are the main component of the mangrove ecosystems. Crab burrows by increasing oxic-anoxic interfaces and facilitating the flux rate between sediment and tidal water affect biogeochemical properties of sediments. The effect of fiddler crab burrows on the density and diversity of bacteria were investigated to elucidate the effect of burrow on bacterial distribution. Samples collected from the burrow walls of three species of fiddler crabs including Uca paradussumieri, Uca rosea, and Uca forcipata. Sediment properties including grain size, temperature, Redox potential, pH, chlorophyll, water and organic content were measured from the burrow walls to assess the correlation between environmental variables and bacterial communities. Bacteria were enumerated with epifluorescence microscopy after staining with SYBR green. Bacterial DNA extracted from sediment samples and the community profiles of bacteria were determined with Terminal Restriction Fragment Length Polymorphism (T-RFLP). High endemism was observed among bacterial communities. Among the 152 observed OTU’s, 22 were found only in crab burrows. The highest bacterial density and diversity were recorded in burrow wall. The results of ANOSIM indicated a significant difference between the bacterial communities from the three species of fiddler crab burrows. Only 3% of explained bacteria variability in the constrained ordination model of CCA was contributed to depth, while much of the bacteria’s variability was attributed to coarse sand, pH, and chlorophyll content. Our findings suggest that crab burrows by affecting sediment properties such as redox potential, pH, water, and chlorophyll content induce significant effects on the bacterial communities.

Keywords: bioturbation, canonical corresponding analysis, fiddler crab, microbial ecology

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3070 Evaluation of the Energy Performance and Emissions of an Aircraft Engine: J69 Using Fuel Blends of Jet A1 and Biodiesel

Authors: Gabriel Fernando Talero Rojas, Vladimir Silva Leal, Camilo Bayona-Roa, Juan Pava, Mauricio Lopez Gomez

Abstract:

The substitution of conventional aviation fuels with biomass-derived alternative fuels is an emerging field of study in the aviation transport, mainly due to its energy consumption, the contribution to the global Greenhouse Gas - GHG emissions and the fossil fuel price fluctuations. Nevertheless, several challenges remain as the biofuel production cost and its degradative effect over the fuel systems that alter the operating safety. Moreover, experimentation on full-scale aeronautic turbines are expensive and complex, leading to most of the research to the testing of small-size turbojets with a major absence of information regarding the effects in the energy performance and the emissions. The main purpose of the current study is to present the results of experimentation in a full-scale military turbojet engine J69-T-25A (presented in Fig. 1) with 640 kW of power rating and using blends of Jet A1 with oil palm biodiesel. The main findings are related to the thrust specific fuel consumption – TSFC, the engine global efficiency – η, the air/fuel ratio – AFR and the volume fractions of O2, CO2, CO, and HC. Two fuels are used in the present study: a commercial Jet A1 and a Colombian palm oil biodiesel. The experimental plan is conducted using the biodiesel volume contents - w_BD from 0 % (B0) to 50 % (B50). The engine operating regimes are set to Idle, Cruise, and Take-off conditions. The turbojet engine J69 is used by the Colombian Air Force and it is installed in a testing bench with the instrumentation that corresponds to the technical manual of the engine. The increment of w_BD from 0 % to 50 % reduces the η near 3,3 % and the thrust force in a 26,6 % at Idle regime. These variations are related to the reduction of the 〖HHV〗_ad of the fuel blend. The evolved CO and HC tend to be reduced in all the operating conditions when increasing w_BD. Furthermore, a reduction of the atomization angle is presented in Fig. 2, indicating a poor atomization in the fuel nozzle injectors when using a higher biodiesel content as the viscosity of fuel blend increases. An evolution of cloudiness is also observed during the shutdown procedure as presented in Fig. 3a, particularly after 20 % of biodiesel content in the fuel blend. This promotes the contamination of some components of the combustion chamber of the J69 engine with soot and unburned matter (Fig. 3). Thus, the substitution of biodiesel content above 20 % is not recommended in order to avoid a significant decrease of η and the thrust force. A more detail examination of the mechanical wearing of the main components of the engine is advised in further studies.

Keywords: aviation, air to fuel ratio, biodiesel, energy performance, fuel atomization, gas turbine

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3069 Investigation of the Drying Times of Blood under Different Environmental Conditions and on Different Fabrics and the Transfer of Blood at Different Times of the Drying Process

Authors: Peter Parkinson

Abstract:

The research investigates the effects of temperature, humidity, wind speed, and fabric composition on the drying times of blood and assesses the degree of blood transfer that can occur during the drying process. An assortment of fabrics, of different composition and thicknesses, were collected and stained using two blood volumes and exposed to varying environmental conditions. The conclusion reached was that temperature, humidity, wind speed, and fabric thickness do have an effect on drying times. An increase in temperature and wind speed results in a decrease in drying times while an increase in fabric thickness and humidity extended the drying times of blood under similar conditions. Transfer experimentation utilized three donor fabrics, 100% white cotton, 100% acrylic, and 100% cotton denim, which were bloodstained using two blood volumes. The fabrics were subjected to both full and low/light force contact from the donor fabrics onto the recipient fabric, under different environmental conditions. Transfer times onto the 100% white cotton (recipient fabric) from all donor fabrics were shorter than the drying times observed. The intensities of the bloodstains decreased from high to low with time during the drying process. The degree of transfer at high, medium, and low intensities varied significantly between different materials and is dependent on the environmental conditions, fabric compositions, blood volumes, the type of contact (full or light force), and the drying times observed for the respective donor fabrics. These factors should be considered collectively and conservatively when assessing the time frame of secondary transfer in casework.

Keywords: blood, drying time, blood stain transfer, different environmental conditions, fabrics

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3068 Semi-Autonomous Surgical Robot for Pedicle Screw Insertion on ex vivo Bovine Bone: Improved Workflow and Real-Time Process Monitoring

Authors: Robnier Reyes, Andrew J. P. Marques, Joel Ramjist, Chris R. Pasarikovski, Victor X. D. Yang

Abstract:

Over the past three decades, surgical robotic systems have demonstrated their ability to improve surgical outcomes. The LBR Med is a collaborative robotic arm that is meant to work with a surgeon to streamline surgical workflow. It has 7 degrees of freedom and thus can be easily oriented. Position and torque sensors at each joint allow it to maintain a position accuracy of 150 µm with real-time force and torque feedback, making it ideal for complex surgical procedures. Spinal fusion procedures involve the placement of as many as 20 pedicle screws, requiring a great deal of accuracy due to proximity to the spinal canal and surrounding vessels. Any deviation from intended path can lead to major surgical complications. Assistive surgical robotic systems are meant to serve as collaborative devices easing the workload of the surgeon, thereby improving pedicle screw placement by mitigating fatigue related inaccuracies. Moreover, robotic spinal systems have shown marked improvements over conventional freehanded techniques in both screw placement accuracy and fusion quality and have greatly reduced the need for screw revision, intraoperatively and post-operatively. However, current assistive spinal fusion robots, such as the ROSA Spine, are limited in functionality to positioning surgical instruments. While they offer a small degree of improvement in pedicle screw placement accuracy, they do not alleviate surgeon fatigue, nor do they provide real-time force and torque feedback during screw insertion. We propose a semi-autonomous surgical robot workflow for spinal fusion where the surgeon guides the robot to its initial position and orientation, and the robot drives the pedicle screw accurately into the vertebra. Here, we demonstrate feasibility by inserting pedicle screws into ex-vivo bovine rib bone. The robot monitors position, force and torque with respect to predefined values selected by the surgeon to ensure the highest possible spinal fusion quality. The workflow alleviates the strain on the surgeon by having the robot perform the screw placement while the ability to monitor the process in real-time keeps the surgeon in the system loop. The approach we have taken in terms of level autonomy for the robot reflects its ability to safely collaborate with the surgeon in the operating room without external navigation systems.

Keywords: ex vivo bovine bone, pedicle screw, surgical robot, surgical workflow

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3067 Analysis of Force Convection in Bandung Triga Reactor Core Plate Types Fueled Using Coolod-N2

Authors: K. A. Sudjatmi, Endiah Puji Hastuti, Surip Widodo, Reinaldy Nazar

Abstract:

Any pretensions to stop the production of TRIGA fuel elements by TRIGA reactor fuel elements manufacturer should be anticipated by the operating agency of TRIGA reactor to replace the cylinder type fuel element with plate type fuel element, that available on the market. This away was performed the calculation on U3Si2Al fuel with uranium enrichment of 19.75% and a load level of 2.96 gU/cm3. Maximum power that can be operated on free convection cooling mode at the BANDUNG TRIGA reactor fuel plate was 600 kW. This study has been conducted thermalhydraulic characteristic calculation model of the reactor core power 2MW. BANDUNG TRIGA reactor core fueled plate type is composed of 16 fuel elements, 4 control elements and one irradiation facility which is located right in the middle of the core. The reactor core is cooled using a pump which is already available with flow rate 900 gpm. Analysis on forced convection cooling mode with flow from the top down from 10%, 20%, 30% and so on up to a 100% rate of coolant flow. performed using the COOLOD-N2 code. The calculations result showed that the 2 MW power with inlet coolant temperature at 37 °C and cooling rate percentage of 50%, then the coolant temperature, maximum cladding and meat respectively 64.96 oC, 124.81 oC, and 125.08 oC, DNBR (departure from nucleate boiling ratio)=1.23 and OFIR (onset of flow instability ratio)=1:00. The results are expected to be used as a reference for determining the power and cooling rate level of the BANDUNG TRIGA reactor core plate types fueled.

Keywords: TRIGA, COOLOD-N2, plate type fuel element, force convection, thermal hydraulic characteristic

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3066 Analysis of Elastic-Plastic Deformation of Reinforced Concrete Shear-Wall Structures under Earthquake Excitations

Authors: Oleg Kabantsev, Karomatullo Umarov

Abstract:

The engineering analysis of earthquake consequences demonstrates a significantly different level of damage to load-bearing systems of different types. Buildings with reinforced concrete columns and separate shear-walls receive the highest level of damage. Traditional methods for predicting damage under earthquake excitations do not provide an answer to the question about the reasons for the increased vulnerability of reinforced concrete frames with shear-walls bearing systems. Thus, the study of the problem of formation and accumulation of damages in the structures reinforced concrete frame with shear-walls requires the use of new methods of assessment of the stress-strain state, as well as new approaches to the calculation of the distribution of forces and stresses in the load-bearing system based on account of various mechanisms of elastic-plastic deformation of reinforced concrete columns and walls. The results of research into the processes of non-linear deformation of structures with a transition to destruction (collapse) will allow to substantiate the characteristics of limit states of various structures forming an earthquake-resistant load-bearing system. The research of elastic-plastic deformation processes of reinforced concrete structures of frames with shear-walls is carried out on the basis of experimentally established parameters of limit deformations of concrete and reinforcement under dynamic excitations. Limit values of deformations are defined for conditions under which local damages of the maximum permissible level are formed in constructions. The research is performed by numerical methods using ETABS software. The research results indicate that under earthquake excitations, plastic deformations of various levels are formed in various groups of elements of the frame with the shear-wall load-bearing system. During the main period of seismic effects in the shear-wall elements of the load-bearing system, there are insignificant volumes of plastic deformations, which are significantly lower than the permissible level. At the same time, plastic deformations are formed in the columns and do not exceed the permissible value. At the final stage of seismic excitations in shear-walls, the level of plastic deformations reaches values corresponding to the plasticity coefficient of concrete , which is less than the maximum permissible value. Such volume of plastic deformations leads to an increase in general deformations of the bearing system. With the specified parameters of the deformation of the shear-walls in concrete columns, plastic deformations exceeding the limiting values develop, which leads to the collapse of such columns. Based on the results presented in this study, it can be concluded that the application seismic-force-reduction factor, common for the all load-bearing system, does not correspond to the real conditions of formation and accumulation of damages in elements of the load-bearing system. Using a single coefficient of seismic-force-reduction factor leads to errors in predicting the seismic resistance of reinforced concrete load-bearing systems. In order to provide the required level of seismic resistance buildings with reinforced concrete columns and separate shear-walls, it is necessary to use values of the coefficient of seismic-force-reduction factor differentiated by types of structural groups.1

Keywords: reinforced concrete structures, earthquake excitation, plasticity coefficients, seismic-force-reduction factor, nonlinear dynamic analysis

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3065 Aseismic Stiffening of Architectural Buildings as Preventive Restoration Using Unconventional Materials

Authors: Jefto Terzovic, Ana Kontic, Isidora Ilic

Abstract:

In the proposed design concept, laminated glass and laminated plexiglass, as ”unconventional materials”, are considered as a filling in a steel frame on which they overlap by the intermediate rubber layer, thereby forming a composite assembly. In this way vertical elements of stiffening are formed, capable for reception of seismic force and integrated into the structural system of the building. The applicability of such a system was verified by experiments in laboratory conditions where the experimental models based on laminated glass and laminated plexiglass had been exposed to the cyclic loads that simulate the seismic force. In this way the load capacity of composite assemblies was tested for the effects of dynamic load that was parallel to assembly plane. Thus, the stress intensity to which composite systems might be exposed was determined as well as the range of the structure stiffening referring to the expressed deformation along with the advantages of a particular type of filling compared to the other one. Using specialized software whose operation is based on the finite element method, a computer model of the structure was created and processed in the case study; the same computer model was used for analyzing the problem in the first phase of the design process. The stiffening system based on composite assemblies tested in laboratories is implemented in the computer model. The results of the modal analysis and seismic calculation from the computer model with stiffeners applied showed an efficacy of such a solution, thus rounding the design procedures for aseismic stiffening by using unconventional materials.

Keywords: laminated glass, laminated plexiglass, aseismic stiffening, experiment, laboratory testing, computer model, finite element method

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