Search results for: adaptive response
2208 Influence of Concrete Cracking in the Tensile Strength of Cast-in Headed Anchors
Authors: W. Nataniel, B. Lima, J. Manoel, M. P. Filho, H. Marcos, Oliveira Mauricio, P. Ferreira
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Headed reinforcement bars are increasingly used for anchorage in concrete structures. Applications include connections in composite steel-concrete structures, such as beam-column joints, in several strengthening situations as well as in more traditional uses in cast-in-place and precast structural systems. This paper investigates the reduction in the ultimate tensile capacity of embedded cast-in headed anchors due to concrete cracking. A series of nine laboratory tests are carried out to evaluate the influence of cracking on the concrete breakout strength in tension. The experimental results show that cracking affects both the resistance and load-slip response of the headed bar anchors. The strengths measured in these tests are compared to theoretical resistances calculated following the recommendations presented by fib Bulletin no. 58 (2011), ETAG 001 (2010) and ACI 318 (2014). The influences of parameters such as the effective embedment depth (hef), bar diameter (ds), and the concrete compressive strength (fc) are analysed and discussed. The theoretical recommendations are shown to be over-conservative for both embedment depths and were, in general, inaccurate in comparison to the experimental trends. The ACI 318 (2014) was the design code which presented the best performance regarding to the predictions of the ultimate load, with an average of 1.42 for the ratio between the experimental and estimated strengths, standard deviation of 0.36, and coefficient of variation equal to 0.25.Keywords: cast-in headed anchors, concrete cone failure, uncracked concrete, cracked concrete
Procedia PDF Downloads 1972207 Photo-Electrochemical/Electro-Fenton Coupling Oxidation System with Fe/Co-Based Anode and Cathode Metal-Organic Frameworks Derivative Materials for Sulfamethoxazole Treatment
Authors: Xin Chen, Xinyong Li, Qidong Zhao, Dong Wang
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A new coupling system was constructed by combining photo-electrochemical cell with electro-fenton cell (PEC-EF). The electrode material in this system was derived from MnyFe₁₋yCo Prussian-Blue-Analog (PBA). Mn₀.₄Fe₀.₆Co₀.₆₇-N@C spin-coated on carbon paper behaved as the gas diffusion cathode and Mn₀.₄Fe₀.₆Co₀.₆₇O₂.₂ spin-coated on fluorine-tin oxide glass (FTO) as anode. The two separated cells could degrade Sulfamethoxazole (SMX) simultaneously and some coupling mechanisms by PEC and EF enhancing the degradation efficiency were investigated. The continuous on-site generation of H₂O₂ at cathode through an oxygen reduction reaction (ORR) was realized over rotating ring-disk electrode (RRDE). The electron transfer number (n) of the ORR with Mn₀.₄Fe₀.₆Co₀.₆₇-N@C was 2.5 in the selected potential and pH range. The photo-electrochemical properties of Mn₀.₄Fe₀.₆Co₀.₆₇O₂.₂ were systematically studied, which displayed good response towards visible light. The photoinduced electrons at anode can transfer to cathode for further use. Efficient photo-electro-catalytic performance was observed in degrading SMX. Almost 100% SMX removal was achieved in 120 min. This work not only provided a highly effective technique for antibiotic treatment but also revealed the synergic effect between PEC and EF.Keywords: electro-fenton, photo-electrochemical, synergic effect, sulfamethoxazole
Procedia PDF Downloads 1742206 Potential of Water Purification of Turbid Surface Water Sources in Remote Arid and Semi-Arid Rural Areas of Rajasthan by Moringa Oleifera (Drumstick) Tree Seeds
Authors: Pomila Sharma
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Rajasthan is among regions with greatest climate sensitivity and lowest adaptive capabilities. In many parts of the Rajasthan surface water which can be highly turbid and contaminated with fecal coliform bacteria is used for drinking purposes. The majority rely almost exclusively upon traditional sources of highly turbid and untreated pathogenic surface water for their domestic water needs. In many parts of rural areas of Rajasthan, it is still difficult to obtain clean water, especially remote habitations with no groundwater due to quality issues or depletion and limited feasibility to connect with surface water schemes due to low density of population in these areas to justify large infrastructure investment. The most viable sources are rain water harvesting, community managed open wells, private wells, ponds and small-scale irrigation reservoirs have often been the main traditional sources of rural drinking water. Turbidity is conventionally removed by treating the water with expensive chemicals. This study has to investigate the use of crushed seeds from the tree Moringa oleifera (drumstick) as a natural alternative to conventional coagulant chemicals. The use of Moringa oleifera seed powder can produce potable water of higher quality than the original source. Moringa oleifera a native species of northern India, the tree is now grown extensively throughout the tropics and found in many countries of Africa, Asia & South America. The seeds of tree contains significant quantities of low molecular weight, water soluble proteins which carries the positive charge when the crushed seeds are added to water. This protein binds in raw water with negatively charged turbid water with bacteria, clay, algae, etc. Under proper mixing, these particles make flocks, which may be left to settle by gravity or be removed by filtration. Using Moringa oleifera as a replacement coagulation in such surface sources of arid and semi-arid areas can meet the need for water purification in remote places of Rajasthan state of India. The present study accesses to find out laboratory based investigation of the effect of seeds of Moringa tree on its coagulation effectiveness (purification) using turbid water samples of surface source of the Rajasthan state. In this study, moringa seed powder showed that filtering with seed powder may diminish water pollution and bacterial counts. Results showed Moringa oleifera seeds coagulate 90-95% of turbidity and color efficiently leading to an aesthetically clear supernatant & reduced about 85-90% of bacterial load reduction in samples.Keywords: bacterial load, coagulant, turbidity, water purification
Procedia PDF Downloads 1362205 Airbnb, Hotel Industry and Optimum Strategies: Evidence from European Cities, Barcelona, London and Paris
Authors: Juan Pedro Aznar Alarcon, Josep Maria Sayeras Maspera
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Airbnb and other similar platforms are offering a near substitute to the traditional accommodation service supplied by the hotel sector. In this context, hotels can try to compete by offering higher quality and additional services, which imply the need for new investments or try to compete by reducing prices. The theoretical model presented in this paper analyzes the best response using a sequential game theory model. The main conclusion is that due to the financial constraints that small and medium hotels have these hotels have reduced prices whereas hotels that belong to international groups or have an easy access to financial resources have increased their investment to increase the quality of the service provided. To check the validity of the theoretical model financial data from Barcelona, London and Paris hotels have been used analyzing profitability, quality of the service provided, the investment propensity and the evolution of the gross profit. The model and the empirical data provide the base for some industrial policy in the hospitality industry. To address the extra cost that small hotels in Europe have to face compared by bigger firms would help to improve the level of quality provided and to some extent have positive externalities in terms of job creation and an increasing added value for the industry.Keywords: Airbnb, profitability, hospitality industry, game theory
Procedia PDF Downloads 3382204 Impacts of Teachers’ Cluster Model Meeting Intervention on Pupils’ Learning, Academic Achievement and Attitudinal Development in Oyo State, Nigeria
Authors: Olusola Joseph Adesina, Abiodun Ezekiel Adesina
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Efforts at improving the falling standard of education in the country call for the need-based assessment of the primary tier of education in Nigeria. Teachers’ cluster meeting intervention is a step towards enhancing the teachers’ professional competency, efficient and effective pupils’ academic achievement and attitudinal development. The study thus determined the impact of the intervention on pupils’ achievement in Oyo State, Nigeria. Three research questions and four hypotheses guided the study. Pre-test, post-test control group, quasi-experimental design was adopted for the study. Eight intact classes from eight different schools were randomly selected into treatment and control groups. Two response instruments, pupils academic achievement test (PAAT; r = 0.87) and pupils attitude to lesson scale (PALS; r = 0.80) were used for data collection. Mean, standard deviation and analysis of covariance (ANCOVA) were used to analyse the collected data. The results showed that the teachers’ cluster meeting have significant impact on pupils academic achievement (F (1,327) =41.79; p<0.05) and attitudinal development (F (1,327) =26.01; p<0.05) in the core subjects of primary schools in Oyo State, Nigeria. The study therefore recommended among others that teachers’ cluster meeting should be sustained for teachers’ professional development and pupils’ upgradement in the State.Keywords: teachers’ cluster meeting, pupils’ academic achievement, pupils’ attitudinal development, academic achievement
Procedia PDF Downloads 4602203 The Effect of Damper Attachment on Tennis Racket Vibration: A Simulation Study
Authors: Kuangyou B. Cheng
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Tennis is among the most popular sports worldwide. During ball-racket impact, substantial vibration transmitted to the hand/arm may be the cause of “tennis elbow”. Although it is common for athletes to attach a “vibration damper” to the spring-bed, the effect remains unclear. To avoid subjective factors and errors in data recording, the effect of damper attachment on racket handle end vibration was investigated with computer simulation. The tennis racket was modeled as a beam with free-free ends (similar to loosely holding the racket). Finite difference method with 40 segments was used to simulate ball-racket impact response. The effect of attaching a damper was modeled as having a segment with increased mass. It was found that the damper has the largest effect when installed at the spring-bed center. However, this is not a practical location due to interference with ball-racket impact. Vibration amplitude changed very slightly when the damper was near the top or bottom of the spring-bed. The damper works only slightly better at the bottom than at the top of the spring-bed. In addition, heavier dampers work better than lighter ones. These simulation results were comparable with experimental recordings in which the selection of damper locations was restricted by ball impact locations. It was concluded that mathematical model simulations were able to objectively investigate the effect of damper attachment on racket vibration. In addition, with very slight difference in grip end vibration amplitude when the damper was attached at the top or bottom of the spring-bed, whether the effect can really be felt by athletes is questionable.Keywords: finite difference, impact, modeling, vibration amplitude
Procedia PDF Downloads 2512202 Comparison Between Vegans and Omnivores on the Recovery of Delayed Onset Muscle Soreness in Young Females
Authors: Njeim Pressila, Hajj-Boutros Guy, Antony D. Karelis
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Background: Acute resistance exercise is associated with an elevated inflammation response, which could lead to delayed onset muscle soreness (DOMS). There is evidence that suggests that ingesting foods that have anti-inflammation properties may help reduce DOMS. A vegan diet has also been shown to be an anti-inflammatory diet which could, in turn, decrease DOMS. Objective and hypothesis: The purpose of the present study will be to compare markers of DOMS between vegans and omnivores after acute resistance exercise in young females. We hypothesize that vegans will have a better recovery of DOMS markers after a resistance exercise session compared to omnivores. Methods: Population: We will recruit30 vegans and 30 omnivores to participate in this study. Allvolunteers will follow either a vegan or an omnivore diet for at least 2 years. Anthropometric measurements, body composition, musclestrength (leg and chest press), markers of DOMS (swelling, pain, and stiffness), and dietary factors, as well as a wellness and anxiety questionnaire will be measured. All participants will also perform an acute resistance exercise session in order to induce DOMS. Pertinence: This project will give us a better understanding on the recovery process of vegans after a resistance training session and, as such, provide useful information to health professionals and athletes/coaches (kinesiologists and nutritionists)Keywords: vgeans, omnivores, delayed onset muscle soreness, pain, stifness
Procedia PDF Downloads 1212201 Leveraging Remote Assessments and Central Raters to Optimize Data Quality in Rare Neurodevelopmental Disorders Clinical Trials
Authors: Pamela Ventola, Laurel Bales, Sara Florczyk
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Background: Fully remote or hybrid administration of clinical outcome measures in rare neurodevelopmental disorders trials is increasing due to the ongoing pandemic and recognition that remote assessments reduce the burden on families. Many assessments in rare neurodevelopmental disorders trials are complex; however, remote/hybrid trials readily allow for the use of centralized raters to administer and score the scales. The use of centralized raters has many benefits, including reducing site burden; however, a specific impact on data quality has not yet been determined. Purpose: The current study has two aims: a) evaluate differences in data quality between administration of a standardized clinical interview completed by centralized raters compared to those completed by site raters and b) evaluate improvement in accuracy of scoring standardized developmental assessments when scored centrally compared to when scored by site raters. Methods: For aim 1, the Vineland-3, a widely used measure of adaptive functioning, was administered by site raters (n= 52) participating in one of four rare disease trials. The measure was also administered as part of two additional trials that utilized central raters (n=7). Each rater completed a comprehensive training program on the assessment. Following completion of the training, each clinician completed a Vineland-3 with a mock caregiver. Administrations were recorded and reviewed by a neuropsychologist for administration and scoring accuracy. Raters were able to certify for the trials after demonstrating an accurate administration of the scale. For site raters, 25% of each rater’s in-study administrations were reviewed by a neuropsychologist for accuracy of administration and scoring. For central raters, the first two administrations and every 10th administration were reviewed. Aim 2 evaluated the added benefit of centralized scoring on the accuracy of scoring of the Bayley-3, a comprehensive developmental assessment widely used in rare neurodevelopmental disorders trials. Bayley-3 administrations across four rare disease trials were centrally scored. For all administrations, the site rater who administered the Bayley-3 scored the scale, and a centralized rater reviewed the video recordings of the administrations and also scored the scales to confirm accuracy. Results: For aim 1, site raters completed 138 Vineland-3 administrations. Of the138 administrations, 53 administrations were reviewed by a neuropsychologist. Four of the administrations had errors that compromised the validity of the assessment. The central raters completed 180 Vineland-3 administrations, 38 administrations were reviewed, and none had significant errors. For aim 2, 68 administrations of the Bayley-3 were reviewed and scored by both a site rater and a centralized rater. Of these administrations, 25 had errors in scoring that were corrected by the central rater. Conclusion: In rare neurodevelopmental disorders trials, sample sizes are often small, so data quality is critical. The use of central raters inherently decreases site burden, but it also decreases rater variance, as illustrated by the small team of central raters (n=7) needed to conduct all of the assessments (n=180) in these trials compared to the number of site raters (n=53) required for even fewer assessments (n=138). In addition, the use of central raters dramatically improves the quality of scoring the assessments.Keywords: neurodevelopmental disorders, clinical trials, rare disease, central raters, remote trials, decentralized trials
Procedia PDF Downloads 1572200 Physico-Chemical Characteristics of Terminalia arjuna Encapsulated Dairy Drink
Authors: Sawale Pravin Digambar, G. R. Patil, Shaik Abdul Hussain
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Terminalia arjuna (TA), an important medicinal plant in Indian System of Medicine, is specifically recognized for its recuperative effect on heart ailments. Alcoholic extract of TA (both free and encapsulated) was incorporated into milk to obtain functional dairy beverages. The respective beverages were appropriately flavored and optimized using response surface methodology to improve the sensory appeal. The beverages were evaluated for their compositional, anti-oxidative and various other physico-chemical aspects. Addition of herb (0.3%) extract to flavoured dairy drink (Drink 1) resulted in significantly lowered (p>0.05) HMF content and increased antioxidant activity, total phenol content as compared with control (Control 1). Subsequently, a significant (p>0.05) increase in acidity and sedimentation was also observed. Encapsulated herb (1.8%) incorporated drink (Drink 2) had significantly (P>0.05) enhanced HMF value and decreased antioxidant activity, phenol content as compared to herb added vanilla chocolate dairy drink (Drink 1). It can be concluded that addition of encapsulated TA extract and non-encapsulated TA extract to chocolate dairy drink at 0.3% concentration altered the functional properties vanilla chocolate dairy drink which could be related to the interaction of herb components such as polyphenol with milk protein or maltodextrin/ gum Arabic matrix.Keywords: Terminalia arjuna, encapsulate, antioxidant activity, physicochemical study
Procedia PDF Downloads 3592199 Students’ Online Forum Activities and Social Network Analysis in an E-Learning Environment
Authors: P. L. Cheng, I. N. Umar
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Online discussion forum is a popular e-learning technique that allows participants to interact and construct knowledge. This study aims to examine the levels of participation, categories of participants and the structure of their interactions in a forum. A convenience sampling of one course coordinator and 23 graduate students was selected in this study. The forums’ log file and the Social Network Analysis software were used in this study. The analysis reveals 610 activities (including viewing forum’s topic, viewing discussion thread, posting a new thread, replying to other participants’ post, updating an existing thread and deleting a post) performed by them in this forum, with an average of 3.83 threads posted. Also, this forum consists of five at-risk participants, six bridging participants, four isolated participants and five leaders of information. In addition, the network density value is 0.15 and there exist five reciprocal interactions in this forum. The closeness value varied between 28 and 68 while the eigen vector centrality value varied between 0.008 and 0.39. The finding indicates that the participants tend to listen more rather than express their opinions in the forum. It was also revealed that those who actively provide supports in the discussion forum were not the same people who received the most responses from their peers. This study found that cliques do not exist in the forum and the participants are not selective to whom they response to, rather, it was based on the content of the posts made by their peers. Based upon the findings, further analysis with different method and population, larger sample size and a longer time frame are recommended.Keywords: e-learning, learning management system, online forum, social network analysis
Procedia PDF Downloads 3802198 Additive Manufacturing Optimization Via Integrated Taguchi-Gray Relation Methodology for Oil and Gas Component Fabrication
Authors: Meshal Alsaiari
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Fused Deposition Modeling is one of the additive manufacturing technologies the industry is shifting to nowadays due to its simplicity and low affordable cost. The fabrication processing parameters predominantly influence FDM part strength and mechanical properties. This presentation will demonstrate the influences of the two manufacturing parameters on the tensile testing evaluation indexes, infill density, and Printing Orientation, which were analyzed to create a piping spacer suitable for oil and gas applications. The tensile specimens are made of two polymers, Acrylonitrile Styrene Acrylate (ASA) and High high-impact polystyrene (HIPS), to characterize the mechanical properties performance for creating the final product. The mechanical testing was carried out per the ASTM D638 testing standard, following Type IV requirements. Taguchi's experiment design using an L-9 orthogonal array was used to evaluate the performance output and identify the optimal manufacturing factors. The experimental results demonstrate that the tensile test is more pronounced with 100% infill for ASA and HIPS samples. However, the printing orientations varied in reactions; ASA is maximum at 0 degrees while HIPS shows almost similar percentages between 45 and 90 degrees. Taguchi-Gray integrated methodology was adopted to minimize the response and recognize optimal fabrication factors combinations.Keywords: FDM, ASTM D638, tensile testing, acrylonitrile styrene acrylate
Procedia PDF Downloads 802197 Computational Approach for Grp78–Nf-ΚB Binding Interactions in the Context of Neuroprotective Pathway in Brain Injuries
Authors: Janneth Gonzalez, Marco Avila, George Barreto
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GRP78 participates in multiple functions in the cell during normal and pathological conditions, controlling calcium homeostasis, protein folding and unfolded protein response. GRP78 is located in the endoplasmic reticulum, but it can change its location under stress, hypoxic and apoptotic conditions. NF-κB represents the keystone of the inflammatory process and regulates the transcription of several genes related with apoptosis, differentiation, and cell growth. The possible relationship between GRP78-NF-κB could support and explain several mechanisms that may regulate a variety of cell functions, especially following brain injuries. Although several reports show interactions between NF-κB and heat shock proteins family members, there is a lack of information on how GRP78 may be interacting with NF-κB, and possibly regulating its downstream activation. Therefore, we assessed the computational predictions of the GRP78 (Chain A) and NF-κB complex (IkB alpha and p65) protein-protein interactions. The interaction interface of the docking model showed that the amino acids ASN 47, GLU 215, GLY 403 of GRP78 and THR 54, ASN 182 and HIS 184 of NF-κB are key residues involved in the docking. The electrostatic field between GRP78-NF-κB interfaces and molecular dynamic simulations support the possible interaction between the proteins. In conclusion, this work shed some light in the possible GRP78-NF-κB complex indicating key residues in this crosstalk, which may be used as an input for better drug design strategy targeting NF-κB downstream signaling as a new therapeutic approach following brain injuries.Keywords: computational biology, protein interactions, Grp78, bioinformatics, molecular dynamics
Procedia PDF Downloads 3372196 Resilient Analysis as an Alternative to Conventional Seismic Analysis Methods for the Maintenance of a Socioeconomical Functionality of Structures
Authors: Sara Muhammad Elqudah, Vigh László Gergely
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Catastrophic events, such as earthquakes, are sudden, short, and devastating, threatening lives, demolishing futures, and causing huge economic losses. Current seismic analyses and design standards are based on life safety levels where only some residual strength and stiffness are left in the structure leaving it beyond economical repair. Consequently, it has become necessary to introduce and implement the concept of resilient design. Resilient design is about designing for ductility over time by resisting, absorbing, and recovering from the effects of a hazard in an appropriate and efficient time manner while maintaining the functionality of the structure in the aftermath of the incident. Resilient analysis is mainly based on the fragility, vulnerability, and functionality curves where eventually a resilience index is generated from these curves, and the higher this index is, the better is the performance of the structure. In this paper, seismic performances of a simple two story reinforced concrete building, located in a moderate seismic region, has been evaluated using the conventional seismic analyses methods, which are the linear static analysis, the response spectrum analysis, and the pushover analysis, and the generated results of these analyses methods are compared to those of the resilient analysis. Results highlight that the resilience analysis was the most convenient method in generating a more ductile and functional structure from a socio-economic perspective, in comparison to the standard seismic analysis methods.Keywords: conventional analysis methods, functionality, resilient analysis, seismic performance
Procedia PDF Downloads 962195 Structural Modeling and Experimental-Numerical Correlation of the Dynamic Behavior of the Portuguese Guitar by Using a Structural-Fluid Coupled Model
Authors: M. Vieira, V. Infante, P. Serrão, A. Ribeiro
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The Portuguese guitar is a pear-shaped plucked chordophone particularly known for its role in Fado, the most distinctive traditional Portuguese musical style. The acknowledgment of the dynamic behavior of the Portuguese guitar, specifically of its modal and mode shape response, has been the focus of different authors. In this research, the experimental results of the dynamic behavior of the guitar, which were previously obtained, are correlated with a vibro-acoustic finite element model of the guitar. The modelling of the guitar offered several challenges which are presented in this work. The results of the correlation between experimental and numerical data are presented and indicate good correspondence for the studied mode shapes. The influence of the air inside the chamber, for the finite element analysis, is shown to be crucial to understand the low-frequency modes of the Portuguese guitar, while, for higher frequency modes, the geometry of the guitar assumes greater relevance. Comparison is made with the classical guitar, providing relevant information about the intrinsic differences between the two, such as between its tones and other acoustical properties. These results represent a sustained base for future work, which will allow the study of the influence of different location and geometry of diverse components of the Portuguese guitar, being as well an asset to the comprehension of its musical properties and qualities and may, furthermore, represent an advantage for its players and luthiers.Keywords: dynamic behavior of guitars, instrument acoustics, modal analysis, Portuguese guitar
Procedia PDF Downloads 3942194 Fire Performance of Fly Ash Concrete with Pre-Fire Load
Authors: Kunjie Fan
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Fly ash has been widely used as supplemental cementitious material in concrete for decades, especially in the ready-mixed concrete industry. Addition of fly ash not only brings economic and environmental benefits but also improves the engineering properties of concrete. It is well known that the pre-fire load has significant impacts on mechanical properties of concrete at high temperatures, however, the fire performance of stressed fly ash concrete is still not clear. Therefore, an apparatus was specially designed for testing “hot” mechanical properties of fly ash concrete with different heating-loading regimes. Through the experimental research, the mechanical properties, including compressive strength, peak strain, elastic modulus, complete stress-strain relationship, and transient thermal creep of fly ash concrete under uniaxial compression at elevated temperatures, have been investigated. It was found that the compressive strength and the elastic modulus increase with the load level, while the peak strain decreases with the applied stress level. In addition, 25% replacement of OPC with FA in the concrete mitigated the deterioration of the compressive strength, the development of transient thermal creep, and the nonlinearity of stress-strain response at elevated temperatures but hardly influenced the value of the elastic modulus and the peak strain. The applicability of Eurocode EN1992-1-2 to normal strength concrete with 25% replacement of fly ash has been verified to be safe. Based on the experimental analysis, an advanced constitutive model for stressed fly ash concrete at high temperatures was proposed.Keywords: fire performance, fly ash concrete, pre-fire load, mechanical properties, transient thermal creep
Procedia PDF Downloads 692193 Low-Dose Chest Computed Tomography Can Help in Differential Diagnosis of Asthma–COPD Overlap Syndrome in Children
Authors: Frantisek Kopriva, Kamila Michalkova, Radim Dudek, Jana Volejnikova
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Rationale: Diagnostic criteria of asthma–COPD overlap syndrome (ACOS) are controversial in pediatrics. Emphysema is characteristic of COPD and usually does not occur in typical asthma; its presence in patients with asthma suggests the concurrence with COPD. Low-dose chest computed tomography (CT) allows a non-invasive assessment of the lung tissue structure. Here we present CT findings of emphysematous changes in a child with ACOS. Patient and Methods: In a 6-year-old boy, atopy was confirmed by a skin prick test using common allergen extracts (grass and tree pollen, house dust mite, molds, cat, dog; manufacturer Stallergenes Greer, London, UK), where reactions over 3 mm were considered positive. Treatment with corticosteroids was started during the course of severe asthma. At 12 years of age, his spirometric parameters deteriorated despite treatment adjustment (VC 1.76 L=85%, FEV1 1.13 L=67%, TI%VCmax 64%, MEF25 19%, TLC 144%) and the bronchodilator test became negative. Results: Low-dose chest CT displayed irregular regions with increased radiolucency of pulmonary parenchyma (typical for hyperinflation in emphysematous changes) in both lungs. This was in accordance with the results of spirometric examination. Conclusions: ACOS is infrequent in children. However, low-dose chest CT scan can be considered to confirm this diagnosis or eliminate other diagnoses when the clinical condition is deteriorating and treatment response is poor.Keywords: child, asthma, low-dose chest CT, ACOS
Procedia PDF Downloads 1402192 Numerical Homogenization of Nacre
Authors: M. Arunachalam, M. Pandey
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Nacre, a biological material that forms the inner-layer of sea shells can achieve high toughness and strength by way of staggered arrangement of strong tablets with soft and weak organic interface. Under applied loads the tablets slide over the adjacent tablets, thus generating inelastic deformation and toughness on macroscopic scale. A two dimensional finite element based homogenization methodology is adopted for obtaining the effective material properties of Nacre using a representative volume element (RVE) at finite deformations. In this work, the material behaviour for tablet and interface are assumed to be Isotropic elastic and Isotropic elastic-perfectly plastic with strain softening respectively. Numerical experiments such as uniaxial tension test along X, Y directions and simple shear test are performed on the RVE with uniform displacement and periodic constraints applied at the RVE boundaries to obtain the anisotropic homogenized response and maximum local stresses within each constituents of Nacre. Homogenized material model is then tested for macroscopic structure under three point bending condition and the results obtained are comparable with the results obtained for detailed microstructure based structure, thus homogenization provides a bridge between macroscopic scale and microscopic scale and homogenized material properties obtained from microstructural (RVE) analysis could be used in large scale structural analysis.Keywords: finite element, homogenization, inelastic deformation, staggered arrangement
Procedia PDF Downloads 3132191 Seismic Integrity Determination of Dams in Urban Areas
Authors: J. M. Mayoral, M. Anaya
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The urban and economic development of cities demands the construction of water use and flood control infrastructure. Likewise, it is necessary to determine the safety level of the structures built with the current standards and if it is necessary to define the reinforcement actions. The foregoing is even more important in structures of great importance, such as dams, since they imply a greater risk for the population in case of failure or undesirable operating conditions (e.g., seepage, cracks, subsidence). This article presents a methodology for determining the seismic integrity of dams in urban areas. From direct measurements of the dynamic properties using geophysical exploration and ambient seismic noise measurements, the seismic integrity of the concrete-faced rockfill dam selected as a case of study is evaluated. To validate the results, two accelerometer stations were installed (e.g., free field and crest of the dam). Once the dynamic properties were determined, three-dimensional finite difference models were developed to evaluate the dam seismic performance for different intensities of movement, considering the site response and soil-structure interaction effects. The seismic environment was determined from the uniform hazard spectra for several return periods. Based on the results obtained, the safety level of the dam against different seismic actions was determined, and the effectiveness of ambient seismic noise measurements in dynamic characterization and subsequent evaluation of the seismic integrity of urban dams was evaluated.Keywords: risk, seismic, soil-structure interaction, urban dams
Procedia PDF Downloads 1012190 Integrating Microcontroller-Based Projects in a Human-Computer Interaction Course
Authors: Miguel Angel Garcia-Ruiz, Pedro Cesar Santana-Mancilla, Laura Sanely Gaytan-Lugo
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This paper describes the design and application of a short in-class project conducted in Algoma University’s Human-Computer Interaction (HCI) course taught at the Bachelor of Computer Science. The project was based on the Maker Movement (people using and reusing electronic components and everyday materials to tinker with technology and make interactive applications), where students applied low-cost and easy-to-use electronic components, the Arduino Uno microcontroller board, software tools, and everyday objects. Students collaborated in small teams by completing hands-on activities with them, making an interactive walking cane for blind people. At the end of the course, students filled out a Technology Acceptance Model version 2 (TAM2) questionnaire where they evaluated microcontroller boards’ applications in HCI classes. We also asked them about applying the Maker Movement in HCI classes. Results showed overall students’ positive opinions and response about using microcontroller boards in HCI classes. We strongly suggest that every HCI course should include practical activities related to tinkering with technology such as applying microcontroller boards, where students actively and constructively participate in teams for achieving learning objectives.Keywords: maker movement, microcontrollers, learning, projects, course, technology acceptance
Procedia PDF Downloads 1652189 Theoretical and Experimental Analysis of Hard Material Machining
Authors: Rajaram Kr. Gupta, Bhupendra Kumar, T. V. K. Gupta, D. S. Ramteke
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Machining of hard materials is a recent technology for direct production of work-pieces. The primary challenge in machining these materials is selection of cutting tool inserts which facilitates an extended tool life and high-precision machining of the component. These materials are widely for making precision parts for the aerospace industry. Nickel-based alloys are typically used in extreme environment applications where a combination of strength, corrosion resistance and oxidation resistance material characteristics are required. The present paper reports the theoretical and experimental investigations carried out to understand the influence of machining parameters on the response parameters. Considering the basic machining parameters (speed, feed and depth of cut) a study has been conducted to observe their influence on material removal rate, surface roughness, cutting forces and corresponding tool wear. Experiments are designed and conducted with the help of Central Composite Rotatable Design technique. The results reveals that for a given range of process parameters, material removal rate is favorable for higher depths of cut and low feed rate for cutting forces. Low feed rates and high values of rotational speeds are suitable for better finish and higher tool life.Keywords: speed, feed, depth of cut, roughness, cutting force, flank wear
Procedia PDF Downloads 2762188 Optimal Sliding Mode Controller for Knee Flexion during Walking
Authors: Gabriel Sitler, Yousef Sardahi, Asad Salem
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This paper presents an optimal and robust sliding mode controller (SMC) to regulate the position of the knee joint angle for patients suffering from knee injuries. The controller imitates the role of active orthoses that produce the joint torques required to overcome gravity and loading forces and regain natural human movements. To this end, a mathematical model of the shank, the lower part of the leg, is derived first and then used for the control system design and computer simulations. The design of the controller is carried out in optimal and multi-objective settings. Four objectives are considered: minimization of the control effort and tracking error; and maximization of the control signal smoothness and closed-loop system’s speed of response. Optimal solutions in terms of the Pareto set and its image, the Pareto front, are obtained. The results show that there are trade-offs among the design objectives and many optimal solutions from which the decision-maker can choose to implement. Also, computer simulations conducted at different points from the Pareto set and assuming knee squat movement demonstrate competing relationships among the design goals. In addition, the proposed control algorithm shows robustness in tracking a standard gait signal when accounting for uncertainty in the shank’s parameters.Keywords: optimal control, multi-objective optimization, sliding mode control, wearable knee exoskeletons
Procedia PDF Downloads 752187 Gender Inequality and Human Trafficking
Authors: Kimberly McCabe
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The trafficking of women and children for abuse and exploitation is not a new problem under the umbrella of human trafficking; however, over the last decade, the problem has attracted increased attention from international governments and non-profits attempting to reduce victimization and provide services for survivors. Research on human trafficking suggests that the trafficking of human beings is, largely, a symptom of poverty. As the trafficking of human beings may be viewed as a response to the demand for people for various forms of exploitation, a product of poverty, and a consequence of the subordinate positions of women and children in society, it reaches beyond randomized victimization. Hence, human trafficking, and especially the trafficking of women and children, goes beyond the realm of poorness. Therefore, to begin to understand the reasons for the existence of human trafficking, one must identify and consider not only the immediate causes but also those underlying structural determinants that facilitate this form of victimization. Specifically, one must acknowledge the economic, social, and cultural factors that support human trafficking. This research attempts to study human trafficking at the country level by focusing on economic, social, and cultural characteristics. This study focuses on inequality and, in particular, gender inequality as related to legislative attempts to address human trafficking. Within the design of this project is the use of the US State Department’s tier classification system for Trafficking in Persons (TIP) and the USA CIA Fact Sheet of country characteristics for over 150 countries in an attempt to model legal outcomes as related to human trafficking. Results of this research demonstrate the significance of characteristics beyond poverty as related to country-level responses to human trafficking.Keywords: child trafficking, gender inequality, human trafficking, inequality
Procedia PDF Downloads 2242186 Failing to Protect Bare Life During the COVID-19 Pandemic: Forced Migrants as Carriers of the Virus
Authors: Claudia Donoso
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This study compares the restriction of mobility of migrants and asylum seekers during the COVID-19 pandemic in the United States and Ecuador. Based on the discourse analysis of anti-migrant rhetoric in press articles, migrant stories in the press, reports, and border control practices, the study examines the Ecuadorian government’s response to the migration flow of Venezuelans and the United States enforcement practices against Latin American asylum seekers. By exploring Giorgio Agamben’s concept of bare life, the article argues that this failure to protect mobility rights is due to the United States and Ecuador’s views of forced migrants as bare life and carriers of the virus, justifying xenophobia, resistance to humanitarian international law, and exceptionalism. By drawing on a feminist intersectional approach, the study adds to recent research on the securitization of forced migration and challenge the race/ethnicity, immigration status, class, and nationality-based discrimination of the measures undertaken during the pandemic. The article illustrates how the treatment of forced migrants as bare life was aggravated by their intersectional inequalities. It concludes by providing recommendations that could be enforced by the US and Ecuadorian governments to protect the right to freedom of mobility.Keywords: bare life, intersectionality, mobility rights, COVID-19, Ecuador, United States
Procedia PDF Downloads 672185 Business Marketing Researches and Analysis Effect on Production
Authors: Mirna John Shawky Demian
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Mobile phones are now one of the direct marketing tools used to reach hard-to-reach consumers. Cell phones are very personal devices that you can carry with you anytime, anywhere. This gives marketers the ability to create personalized marketing messages and send them at the right time and place. The study examined consumer attitudes towards mobile marketing, particularly SMS marketing. Unlike similar studies, this study does not focus on young people, but the field study included consumers between the ages of 18 and 70.The results showed that the majority of participants found SMS marketing destructive. The biggest problem with SMS marketing is subscribing to message lists without the recipient's consent; large number of messages sent; and the irrelevance of message content. Experiential marketing is an unforgettable experience that remains deeply anchored in the customer's memory. Furthermore, customer satisfaction is defined as the emotional response to the experience provided to the customer in relation to specific products or services purchased. Therefore, experiential marketing activities can influence the level of customer satisfaction and loyalty.In this context, the study aims to examine the relationship between experiential marketing, customer satisfaction and loyalty to beauty products in Konya. The results of this study showed that experiential marketing is an important indicator of customer satisfaction and loyalty and that experiential marketing has a significant positive impact on customer satisfaction and loyalty.Keywords: direct marketing, mobile phones mobile marketing, sms advertising, marketing sponsorship, marketing communication theories, marketing communication tools
Procedia PDF Downloads 372184 Colour Change and melenophores response in ateleost: Balantiochilous melenopterus (Bleeker) with Certain Chemicals and Drugs
Authors: Trapti Pathak
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Fishes can change their body colour according to their surroundings by. They do so by either aggregation or dispersion of melanosomes within the skin. These movements can regulate by means of sympathetic nerves with the help of cytoskeleton. Employing the melanophores on isolated scales of the fingerling of teleost fish, it is attempted to characterise the concerned nerves and the receptors located on melenocytes along with implication of microtubules a part of cytoskeleton in the pigmentary translocation in the fish. The scales from dorso-lateral trunk of the fish represented the sympathetic– neuromelanophore preparations which were stimulated by chemical means, such as adrenergic agonist, antagonist and the microtubule-disrupting drugs such as yuhombine, dopamine, colchicine etc. Adrenaline is an adrenergic agonist which is strongly induced the dorse-dependent concentration of pigment in innervated melanophores while Yohimbine is an adrenergic antagonist which is known to block effectively the α2-adrenoceptors inhibited the action of adrenaline. Colchicine effectively interferes with melanosome aggregating action of adrenaline. From these results it is concluded that the chromatic fibres of adrenergic nature innervate the melanophores and these cells do possess α2-adrenoceptors which mediate the melanosome aggregation and the movements of pigment granules through microtubules means of transport within the cell. These movements of pigment are linked to paling or darkening achieved of teleost fish respectively when they approach to their background.Keywords: melenophores, agonists, antagonist, colour change
Procedia PDF Downloads 682183 Effects of a Bacteria-Based Probiotic on Subpopulations of Peripheral Leukocytes and Their Interleukin mRNA Expression in Calves
Authors: Abdul Qadir Qadis, Satoru Goya, Minoru Yatsu, Yu-uki Yoshida, Toshihiro Ichijo, Shigeru Sato
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Bacterial probiotics are known to modulate the gut-associated lymphoid and epithelial tissue response to enhance the activities of intestinal and systemic immune system in human and animals. In cattle, the immune-stimulatory effects of probiotics have been evaluated during intestinal disorders. To investigate the effects of probiotic on the function of peripheral blood mononuclear cells, eight healthy Holstein calves (10 ± 3 weeks) were assigned to a 4 × 2 experimental design. The probiotic, consisting of Lactobacillus plantarum, Enterococcus faecium and Clostridium butyricum, was administered orally at 3.0 g/100 kg body weight to calves once daily for 5 consecutive days. Calves given no probiotic served as the control. In the treatment group, increases in numbers of CD282+ monocytes, CD3+ T-cells and CD4+, CD8+ and WC1+ γδ T- cell subsets were noted on day 7 post-placement compared to pre-dose day and the control group. Expression of interleukin-6, interferon-gamma and tumor necrosis factor-alpha was elevated in peripheral leukocytes on days 7 and 14. These results suggest that peripheral blood leukocytes in healthy calves may be stimulated via the gastrointestinal microbiota, which was increased by the oral probiotic treatment. The 5-day repeated administration of a bacterial probiotic may enhance cellular immune function in weaned calves.Keywords: bacterial-probiotic, calf, interleukin, leukocyte
Procedia PDF Downloads 6512182 Pragmatic Strategies of Selected Online Articles on the Buhari/Jubril Dilemma
Authors: Oluwaseun Amusa
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The online space has continued to be a platform for not only private and mundane discussions but also a tribune for voicing critical political and national opinions. Nigerians and the international community have employed the online media, as well as other media platforms to articulate their thoughts on the claims which favour possibilities of the demise of the incumbent president of Nigeria, President Muhammadu Buhari, after a prolonged illness in year 2007 and the ploy of a Jubril of Sudan clone in his place. This study thus examines the pragmatic strategies employed in the online articles on the national dilemma caused by the Buhari/Jubril claims and refutals, in response to the lacuna in the literature on such analytical investigations on the subject. Two online articles titled, 'Buhari: The real, the fake and the dead' and 'Taking the Buhari/Jubril story seriously', authored by two Nigerian writers, Tunde Odesola and Abimbola Adelakun, respectively and retrieved online from 360nobs.com and Nairaland blogs, on December 3, 2018, and December 7, 2018, respectively, served as data for the study. The data were analysed using the Stance Theory and the Pragmatic Act Theory. Findings showed that the writers employed stance acts, rhetorical questions, metaphors, histo-political allusions, name-calling, and derogatives, in achieving the pragmeme of disabusing. This results in a pragmatic reconstruction of readers' views on the issue.Keywords: Buhari/Jubril claims, online articles, pragmatic strategies, stance theory
Procedia PDF Downloads 1382181 Graphene Reinforced Magnesium Metal Matrix Composites for Biomedical Applications
Authors: Khurram Munir, Cuie Wen, Yuncang Li
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Magnesium (Mg) metal matrix composites (MMCs) reinforced with graphene nanoplatelets (GNPs) have been developed by powder metallurgy (PM). In this study, GNPs with different concentrations (0.1-0.3 wt.%) were dispersed into Mg powders by high-energy ball-milling processes. The microstructure and resultant mechanical properties of the fabricated nanocomposites were characterized using transmission electron microscopy (TEM), scanning electron microscopy (SEM), energy dispersive X-ray spectroscopy (EDX), X-ray diffraction (XRD), Raman spectroscopy (RS), compression and nano-wear tests. The corrosion resistance of the fabricated composites was evaluated by electrochemical tests and hydrogen evolution measurements. Finally, the biological response of Mg-GNPs composites was assessed using osteoblast-like SaOS2 cells. The results indicate that GNPs are excellent candidates as reinforcements in Mg matrices for the manufacture of biodegradable Mg-based composite implants. GNP addition improved the mechanical properties of Mg via synergetic strengthening modes. Moreover, retaining the structural integrity of GNPs during PM processing improved the ductility, compressive strength, and corrosion resistance of the Mg-GNP composites as compared to monolithic Mg. Cytotoxicity assessments did not reveal any significant toxicity with the addition of GNPs to Mg matrices. This study demonstrates that Mg-xGNPs with x < 0.3 wt.%, may constitute novel biodegradable implant materials for load-bearing applications.Keywords: magnesium-graphene composites, strengthening mechanisms, In vitro cytotoxicity, biocorrosion
Procedia PDF Downloads 1492180 Delayed Contralateral Prophylactic Mastectomy (CPM): Reasons and Rationale for Patients with Unilateral Breast Cancer
Authors: C. Soh, S. Muktar, C. M. Malata, J. R. Benson
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Introduction Reasons for requesting CPM include prevention of recurrence, peace of mind and moving on after breast cancer. Some women seek CPM as a delayed procedure but factors influencing this are poorly understood. Methods A retrospective analysis examined patients undergoing CPM as either an immediate or delayed procedure with or without breast reconstruction (BR) between January 2009 and December 2019. A cross-sectional survey based on validated questionnaires (5 point Likert scale) explored patients’ decision-making process in terms of timing of CPM and any BR. Results A total of 123 patients with unilateral breast cancer underwent CPM with 39 (32.5%) delayed procedures with or without BR. The response rate amongst patients receiving questionnaires (n=33) was 22/33 (66%). Within this delayed CPM cohort were three reconstructive scenarios 1) unilateral immediate BR with CPM (n=12); 2) delayed CPM with concomitant bilateral BR (n=22); 3) delayed bilateral BR after delayed CPM (n=3). Two patients had delayed CPM without BR. The most common reason for delayed CPM was to complete all cancer treatments (including radiotherapy) before surgery on the unaffected breast (score 2.91). The second reason was unavailability of genetic test results at the time of therapeutic mastectomy (score 2.64) whilst the third most cited reason was a subsequent change in family cancer history. Conclusion Factors for delayed CPM are patient-driven with few women spontaneously changing their mind having initially decided against immediate CPM for reasons also including surgical duration. CPM should be offered as a potentially delayed option with informed discussion of risks and benefits.Keywords: Breast Cancer, CPM, Prophylactic, Rationale
Procedia PDF Downloads 1082179 The Mechanical Characteristics of Rammed Earth with Plastic Fibers
Authors: Majdi Al Shdifat, Juan Chiachio, Esther Puertas, María L. Jalón, Álvaro Blanca-Hoyos
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In recent years, the world has begun to adopt more sustainable practices in response to today's environmental and climate challenges. The construction sector is one of the most resource-intensive among others, so researchers are testing different types of materials with different processes and methodologies to achieve more environmentally and sustainably friendly buildings. Plastic is one of the most harmful materials for the environment. The global production of plastics has increased dramatically in recent decades, and it is one of the most widely used materials. However, plastic waste is not biodegradable and has a chemical composition that is stable for many years in the environment, both on land and in water bodies. Recycled plastics have been tested to be used in construction in many ways to reduce the amount of plastic in the environment and the use of raw materials in construction. In this context, the main objective of this research is to test the use of plastic fibers with one of the most promising materials to replace cement, which is rammed earth. In fact, rammed earth is considered one of the most environmentally friendly materials due to its use of local raw materials, recyclability, and low embodied energy. In this research, three different types of plastic fibers were used. Then, the blends were evaluated by considering their mechanical properties, including compressive strength and tensile strength. In addition, the non-destructive ultrasonic wave velocity was measured. The result shows excellent potential for the use of plastic fibers in rammed earth, especially in terms of compressive strength.Keywords: mechanical characterization, plastic fibers reinforcement, rammed earth, sustainable material
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