Search results for: physical learning environment
Commenced in January 2007
Frequency: Monthly
Edition: International
Paper Count: 19430

Search results for: physical learning environment

5570 Application of Continuum Damage Concept to Simulation of the Interaction between Hydraulic Fractures and Natural Fractures

Authors: Anny Zambrano, German Gonzalez, Yair Quintero

Abstract:

The continuum damage concept is used to study the interaction between hydraulic fractures and natural fractures, the objective is representing the path and relation among this two fractures types and predict its complex behavior without the need to pre-define their direction as occurs in other finite element applications, providing results more consistent with the physical behavior of the phenomenon. The approach uses finite element simulations through Abaqus software to model damage fracturing, the fracturing process by damage propagation in a rock. The modeling the phenomenon develops in two dimensional (2D) so that the fracture will be represented by a line and the crack front by a point. It considers nonlinear constitutive behavior, finite strain, time-dependent deformation, complex boundary conditions, strain hardening and softening, and strain based damage evolution in compression and tension. The complete governing equations are provided and the method is described in detail to permit readers to replicate all results. The model is compared to models that are published and available. Comparisons are focused in five interactions between natural fractures (NF) and hydraulic fractures: Fractured arrested at NF, crossing NF with or without offset, branching at intersecting NFs, branching at end of NF and NF dilation due to shear slippage. The most significant new finding is, that is not necessary to use pre-defined addresses propagation and stress condition can be evaluated as a dominant factor in the process. This is important because it can model in a more real way the generated complex hydraulic fractures, and be a valuable tool to predict potential problems and different geometries of the fracture network in the process of fracturing due to fluid injection.

Keywords: continuum damage, hydraulic fractures, natural fractures, complex fracture network, stiffness

Procedia PDF Downloads 331
5569 Peculiarities of Internal Friction and Shear Modulus in 60Co γ-Rays Irradiated Monocrystalline SiGe Alloys

Authors: I. Kurashvili, G. Darsavelidze, T. Kimeridze, G. Chubinidze, I. Tabatadze

Abstract:

At present, a number of modern semiconductor devices based on SiGe alloys have been created in which the latest achievements of high technologies are used. These devices might cause significant changes to networking, computing, and space technology. In the nearest future new materials based on SiGe will be able to restrict the A3B5 and Si technologies and firmly establish themselves in medium frequency electronics. Effective realization of these prospects requires the solution of prediction and controlling of structural state and dynamical physical –mechanical properties of new SiGe materials. Based on these circumstances, a complex investigation of structural defects and structural-sensitive dynamic mechanical characteristics of SiGe alloys under different external impacts (deformation, radiation, thermal cycling) acquires great importance. Internal friction (IF) and shear modulus temperature and amplitude dependences of the monocrystalline boron-doped Si1-xGex(x≤0.05) alloys grown by Czochralski technique is studied in initial and 60Co gamma-irradiated states. In the initial samples, a set of dislocation origin relaxation processes and accompanying modulus defects are revealed in a temperature interval of 400-800 ⁰C. It is shown that after gamma-irradiation intensity of relaxation internal friction in the vicinity of 280 ⁰C increases and simultaneously activation parameters of high temperature relaxation processes reveal clear rising. It is proposed that these changes of dynamical mechanical characteristics might be caused by a decrease of the dislocation mobility in the Cottrell atmosphere enriched by the radiation defects.

Keywords: internal friction, shear modulus, gamma-irradiation, SiGe alloys

Procedia PDF Downloads 137
5568 Non-Contact Measurement of Soil Deformation in a Cyclic Triaxial Test

Authors: Erica Elice Uy, Toshihiro Noda, Kentaro Nakai, Jonathan Dungca

Abstract:

Deformation in a conventional cyclic triaxial test is normally measured by using point-wise measuring device. In this study, non-contact measurement technique was applied to be able to monitor and measure the occurrence of non-homogeneous behavior of the soil under cyclic loading. Non-contact measurement is executed through image processing. Two-dimensional measurements were performed using Lucas and Kanade optical flow algorithm and it was implemented Labview. In this technique, the non-homogeneous deformation was monitored using a mirrorless camera. A mirrorless camera was used because it is economical and it has the capacity to take pictures at a fast rate. The camera was first calibrated to remove the distortion brought about the lens and the testing environment as well. Calibration was divided into 2 phases. The first phase was the calibration of the camera parameters and distortion caused by the lens. The second phase was to for eliminating the distortion brought about the triaxial plexiglass. A correction factor was established from this phase. A series of consolidated undrained cyclic triaxial test was performed using a coarse soil. The results from the non-contact measurement technique were compared to the measured deformation from the linear variable displacement transducer. It was observed that deformation was higher at the area where failure occurs.

Keywords: cyclic loading, non-contact measurement, non-homogeneous, optical flow

Procedia PDF Downloads 297
5567 Repeated Dose 28-Day Oral Toxicity Study Offungicides: Propinèbe, Propiconazole, And Their Mixture in Wistar Rats

Authors: Aiche Mohamed Amine, Mallem Leila, Yahia El Khansa, Boulakoud Mohamed Salah

Abstract:

Until recently, toxicological studies focused on the effects of individual chemicals. However, humans and wildlife are exposed to a complex milieu of chemicals from different sources including food and water, personal care products and the environment. The aim of this study is to detect the toxicity of two fungicides and their mixtures in the fertility and oxidative damge induced in the rat. The male of rats (28) were used, they were divided in four groups (7 rats of each group) and one group was used as control. Rats were dosed orally with Propiconazole 60mg/Kg/day, Propinebe 100mg/Kg/day and their mixture 30mg Propiconazole/kg/day + 50mg Propineb/kg/day for 4 weeks. Animals were observed for clinical toxicity. At the end of treatment period, animals of all groups were scarified, blood was collected for hematological and biochemical’s analysis and desired organs were removed and weighted. The results indicated that the fungicide and their mixture were toxic in the treated animals. The semen study showed a decrease in the count and mobility of spermatozoa in all treated group, it was also a decrease in the weight of the testis and epidydimis in the treated group as compared with control. Reduced glutathione (GSH), Glutathione peroxidase (GPx) level was decreased in all treated groups.

Keywords: fungicides, mixtures, fertility, oxidative stress

Procedia PDF Downloads 414
5566 A Review of Paleo-Depositional Environment and Thermal Alteration Index of Carboniferous, Permian and Triassic of A1-9 well, NW Libya

Authors: Mohamed Ali Alrabib

Abstract:

This paper introduces a paleoenvironmental and hydrocarbon show in this well was identified in the interval of Dembaba formation to the Hassaona formation was poor to very poor oil show. And from palaeoenvironmental analysis there is neither particularly good reservoir nor source rock have been developed in the area. Recent palaeoenvironment work undertakes that the sedimentary succession in this area comprises the Upper Paleozoic rock of the Carboniferous and Permian and the Mesozoic (Triassic) sedimentary sequences. No early Paleozoic rocks have been found in this area, these rocks were eroding during the Late Carboniferous and Early Permian time. During Latest Permian and earliest Triassic time evidence for major marine transgression has occurred. From depths 5930-5940 feet, to 10800-10810 feet, the TAI of the Al Guidr, the Bir Al Jaja Al Uotia, Hebilia and the top varies between 3+ to 4-(mature-dry gas). This interval corporate the rest part of the Dembaba Formation. From depth 10800- 10810 feet, until total sediment depth (11944 feet Log) which corporate the rest of the Dembaba and underlying equivalents of the Assedjefar and M rar Formations and the underlying Indeterminate unit (Hassouna Formation) the TAI varies between 4 and 5 (dry gas-black& deformed).

Keywords: paleoenveronments, thermail index, carboniferous, Libya

Procedia PDF Downloads 429
5565 The Impact of the Training Program Provided by the Saudi Archery Federation on the Electromyography of the Bow Arm Muscles

Authors: Hana Aljumayi, Mohammed Issa

Abstract:

The aim of this study was to investigate the effect of the training program for professional athletes at the Saudi Archery Federation on the electrical activity of the muscles involved in pulling the bowstring, maximum muscle strength (MVC) and to identify the relationship between the electrical activity of these muscles and accuracy in shooting among female archers. The researcher used a descriptive approach that was suitable for the nature of the study, and a sample of nine female archers was selected using purposive sampling. An EMG device was used to measure signal amplitude, signal frequency, spectral energy signal, and MVC. The results showed statistically significant differences in signal amplitude among muscles, with F(8,1)=5.91 and a significance level of 0.02. There were also statistically significant differences between muscles in terms of signal frequency, with F(8,1)=8.23 and a significance level of 0.02. Bonferroni test results indicated statistically significant differences between measurements at a significance level of 0.05, with anterior measurements showing an average difference of 16.4 compared to other measurements. Furthermore, there was a significant negative correlation between signal amplitude in the calf muscle and accuracy in shooting (r=-0.78) at a significance level of 0.02. There was also a significant positive correlation between signal frequency in the calf muscle and accuracy in shooting (r=0.72) at a significance level of 0.04. In conclusion, it appears that the training program for archery athletes focused more on skill development than physical aspects such as muscle activity and strength development. However, it did have a statistically significant effect on signal amplitude but not on signal frequency or MVC development in muscles involved in pulling the bowstring.

Keywords: electrical activity of muscles, archery sport, shooting accuracy, muscles

Procedia PDF Downloads 59
5564 Response of Diaphragmatic Excursion to Inspiratory Muscle Trainer Post Thoracotomy

Authors: H. M. Haytham, E. A. Azza, E.S. Mohamed, E. G. Nesreen

Abstract:

Thoracotomy is a great surgery that has serious pulmonary complications, so purpose of this study was to determine the response of diaphragmatic excursion to inspiratory muscle trainer post thoracotomy. Thirty patients of both sexes (16 men and 14 women) with age ranged from 20 to 40 years old had done thoracotomy participated in this study. The practical work was done in cardiothoracic department, Kasr-El-Aini hospital at faculty of medicine for individuals 3 days Post operatively. Patients were assigned into two groups: group A (study group) included 15 patients (8 men and 7 women) who received inspiratory muscle training by using inspiratory muscle trainer for 20 minutes and routine chest physiotherapy (deep breathing, cough and early ambulation) twice daily, 3 days per week for one month. Group B (control group) included 15 patients (8 men and 7 women) who received the routine chest physiotherapy only (deep breathing, cough and early ambulation) twice daily, 3 days per week for one month. Ultrasonography was used to evaluate the changes in diaphragmatic excursion before and after training program. Statistical analysis revealed a significant increase in diaphragmatic excursion in the study group (59.52%) more than control group (18.66%) after using inspiratory muscle trainer post operatively in patients post thoracotomy. It was concluded that the inspiratory muscle training device increases diaphragmatic excursion in patients post thoracotomy through improving inspiratory muscle strength and improving mechanics of breathing and using of inspiratory muscle trainer as a method of physical therapy rehabilitation to reduce post-operative pulmonary complications post thoracotomy.

Keywords: diaphragmatic excursion, inspiratory muscle trainer, ultrasonography, thoracotomy

Procedia PDF Downloads 316
5563 Flipped Classroom Instruction: Reflecting on the Experiences of Teachers and Students at Undergraduate University Level

Authors: Mubeshera Tufail

Abstract:

The purpose of the study was to explore the experiences and challenges faced by teachers and students with Flipped Classroom Instruction (FCI) for an undergraduate course at university level. The Flipped Classroom lesson plan consisted of two components: one was out-of-class component consisting of learning material for reading for students and other was within-class component involving a class quiz, class activity and the feedback/further reading task. Besides, experiences, the research study also covered the adaptations made to improve their experiences with Flipped Classroom during the study. The phenomenological research strategy was used for this research study. The data consisted of weekly reflective journals documented by class teacher and students. The reflective journals were recorded by teacher and students while working in Flipped Classroom for an undergraduate course at university level. The main challenges highlighted by teacher were related to effort and time required for planning, time management and students' guidance for shift of their role from passive to independent learner. The main challenges found in reflective journals of students were personal computers issue, electricity and internet speed issue. It is recommended to adapt to some locally useful lesson planning and classroom management techniques to enhance the effectiveness of Flipped Classroom Instruction in an undergraduate university level course.

Keywords: flipped classroom instruction, undergraduate students, independent learner, technology-integrated classroom

Procedia PDF Downloads 157
5562 Hydrothermal Liquefaction for Astaxanthin Extraction from Wet Algae

Authors: Spandana Ramisetty, Mandan Chidambaram, Ramesh Bhujade

Abstract:

Algal biomass is not only a potential source for biocrude but also for high value chemicals like carotenoids, fatty acids, proteins, polysaccharides, vitamins etc. Astaxanthin is one such high value vital carotenoid which has extensive applications in pharmaceutical, aquaculture, poultry and cosmetic industries and expanding as dietary supplement to humans. Green microalgae Haematococcus pluvialis is identified as the richest natural source of astaxanthin and is the key source of commercial astaxanthin. Several extraction processes from wet and dry Haematococcus pluvialis biomass have been explored by researchers. Extraction with supercritical CO₂ and various physical disruption techniques like mortar and pestle, homogenization, ultrasonication and ball mill from dried algae are widely used extraction methods. However, these processes require energy intensive drying of biomass that escalates overall costs notably. From the process economics perspective, it is vital to utilize wet processing technology in order to eliminate drying costs. Hydrothermal liquefaction (HTL) is a thermo-chemical conversion process that converts wet biomass containing over 80% water to bio-products under high temperature and high pressure conditions. Astaxanthin is a lipid soluble pigment and is usually extracted along with lipid component. Mild HTL at 200°C and 60 bar has been demonstrated by researchers in a microfluidic platform achieving near complete extraction of astaxanthin from wet biomass. There is very limited work done in this field. An integrated approach of sequential HTL offers cost-effective option to extract astaxanthin/lipid from wet algal biomass without drying algae and also recovering water, minerals and nutrients. This paper reviews past work and evaluates the astaxanthin extraction processes with focus on hydrothermal extraction.

Keywords: astaxanthin, extraction, high value chemicals, hydrothermal liquefaction

Procedia PDF Downloads 304
5561 Comparative Policy Analysis on Agropolitan Territorial Development in Rural Area: A Study Case in Bojonegoro Regency, Indonesia

Authors: Fatihin Khoirul, Muhammad Muqorrobin Ist

Abstract:

Bojonegoro Regency is one of the districts that use the concept Agropolitan as the Territorial Development Policy. Three sub-district designated as Area Development District of Agropolitan are Kapas, Dander, and Kalitidu or commonly called KADEKA. Current policy has been shown results, but there was an inequality of results in some areas. One of them occurred in the Ngringinrejo village with the main commodities is Starfruit and Wedi village with the main commodities is Salak fruit. Therefore, a comparative study is used to search for causal factors of inequality result of the policy by using the 5 aspects compared, namely: (1) Management Development Agropolitan; (2) Physical Condition agropolitan Region; (3) Implementing Agency at the Village Level; (4) Village Government Support; and (5) Community support. Based on the discussion of qualitative analysis, it was found that five aspects have their respective roles in creating inequality of outcomes that occur in both villages. But beyond that, there are conditions where the two villages experienced the same condition that is when the initial implementation of the policy. The condition is referred to as 'the phenomenon of price trap.' The condition is caused by lower commodity prices, causing the village government's commitment in implementing policies too low, followed by public awareness in support of the policy is also low, so care for commodities is also low, and the quality is too low lead and eventually back causing low price. However, the difference is that the village Ngringinrejo able to get out of this condition with 'the new culture of administration' at the end of 2013. While the conditions in the village of Wedi compounded by not respected request assistance by the irrigation district.

Keywords: comparative policy analysis, qualitative comparative, inequallity, price trap, new culture of administration

Procedia PDF Downloads 281
5560 Degradation of Chlorpyrifos Pesticide in Aqueous Solution and Chemical Oxygen Demand from Real Effluent with Hydrodynamic Cavitation Approach

Authors: Shrikant Randhavane, Anjali Khambete

Abstract:

Use of Pesticides is vital in attaining food security and protection from harmful pests and insects in living environment. Chlorpyrifos, an organophosphate pesticide is widely used worldwide for various purposes. Due to its wide use and applications, its residues are found in environmental matrices and persist in nature for long duration of time. This has an adverse effect on human, aquatic and living bodies. Use of different methodologies is need of an hour to treat such type of recalcitrant compound. The paper focuses on Hydrodynamic Cavitation (HC), a hybrid Advanced Oxidation Potential (AOP) method to degrade Chlorpyrifos in aqueous water. Obtained results show that optimum inlet pressure of 5 bars gave maximum degradation of 99.25% for lower concentration and 87.14% for higher concentration Chlorpyrifos solution in 1 hour treatment time. Also, with known initial concentrations, comparing treatment time with optimum pressure of 5 bars, degradation efficiency increases with Hydrodynamic Cavitation. The potential application of HC in removal of Chemical Oxygen Demand (COD) from real effluent with venturi as cavitating device reveals around 40% COD removal with 1 hour of treatment time.

Keywords: advanced oxidation potential, cavitation, chlorpyrifos, COD

Procedia PDF Downloads 214
5559 The Effect of Acrylic Gel Grouting on Groundwater in Porous Media

Authors: S. Wagner, C. Boley, Y. Forouzandeh

Abstract:

When digging excavations, groundwater bearing layers are often encountered. In order to allow anhydrous excavation, soil groutings are carried out, which form a water-impermeable layer. As it is injected into groundwater areas, the effects of the materials used on the environment must be known. Developing an eco-friendly, economical and low viscous acrylic gel which has a sealing effect on groundwater is therefore a significant task. At this point the study begins. Basic investigations with the rheometer and a reverse column experiment have been performed with different mixing ratios of an acrylic gel. A dynamic rheology study was conducted to determine the time at which the gel still can be processed and the maximum gel strength is reached. To examine the effect of acrylic gel grouting on determine the parameters pH value, turbidity, electric conductivity, and total organic carbon on groundwater, an acrylic gel was injected in saturated sand filled the column. The structure was rinsed with a constant flow and the eluate was subsequently examined. The results show small changes in pH values and turbidity but there is a dependency between electric conductivity and total organic carbon. The curves of the two parameters react at the same time, which means that the electrical conductivity in the eluate can be measured constantly until the maximum is reached and only then must total organic carbon (TOC) samples be taken.

Keywords: acrylic gel grouting, dynamic rheology study, electric conductivity, total organic carbon

Procedia PDF Downloads 142
5558 A Systematic Review for Promotion of Sustainable Fisheries and Aquaculture: A Global Perspective

Authors: Soma Gholamveisy, Vahid Mirghavameddin

Abstract:

Aquaculture activities face wide environmental, social, and economic problems today. To deal with these problems, the aquaculture business, which is already a highly significant agricultural activity, is influenced by sustainability, which can assure the rural community's safety and food health with minimal environmental damage. The objective of this study's systematic review of the literature (SLR) is to look into the use of global perspective Promotion of Sustainable Fisheries and Aquaculture. SLR aims to identify the goals of a promotional system, also one of its main components. This research seeks to empower, increase economic productivity, facilitate, pay more attention to the sustainability of the environment and inform the audience in this regard. A method used to assess hypotheses, condense the results of past studies or verify the consistency of studies. It presents a succinct analysis of original research using an unambiguous and verifiable approach. A thorough repository with a vast array of papers and effective exploration methods are frequently utilized in a systematic literature review, enabling the application of advanced logical statements. A comprehensive literature review was carried out to ensure that the most relevant studies were included. This type of review clarifies publication selection criteria and allows evaluation of the studies conducted and their repetition or extension.

Keywords: systematic review, sustainable, fisheries, aquaculture

Procedia PDF Downloads 90
5557 Perception of Secondary Schools’ Students on Computer Education in Federal Capital Territory (FCT-Abuja), Nigeria

Authors: Salako Emmanuel Adekunle

Abstract:

Computer education is referred to as the knowledge and ability to use computers and related technology efficiently, with a range of skills covering levels from basic use to advance. Computer continues to make an ever-increasing impact on all aspect of human endeavours such as education. With numerous benefits of computer education, what are the insights of students on computer education? This study investigated the perception of senior secondary school students on computer education in Federal Capital Territory (FCT), Abuja, Nigeria. A sample of 7500 senior secondary schools students was involved in the study, one hundred (100) private and fifty (50) public schools within FCT. They were selected by using simple random sampling technique. A questionnaire [PSSSCEQ] was developed and validated through expert judgement and reliability co-efficient of 0.84 was obtained. It was used to gather relevant data on computer education. Findings confirmed that the students in the FCT had positive perception on computer education. Some factors were identified that affect students’ perception on computer education. The null hypotheses were tested using t-test and ANOVA statistical analyses at 0.05 level of significance. Based on these findings, some recommendations were made which include competent teachers should be employed into all secondary schools; this will help students to acquire relevant knowledge in computer education, technological supports should be provided to all secondary schools; this will help the users (students) to solve specific problems in computer education and financial supports should be provided to procure computer facilities that will enhance the teaching and the learning of computer education.

Keywords: computer education, perception, secondary school, students

Procedia PDF Downloads 458
5556 Cladode features in Opuntia ficus-indica resistant cultivars to Dactylopius coccus Costa

Authors: Yemane Kahsay Berhe

Abstract:

The multipurpose cactus pear plant with great potential as a source of food and livestock feed faced a threat from Dactylopius spp in different countries. Specifically, D. coccus is an important pest damaging significant areas in Tigray-Ethiopia. Using pest-resistant cultivars is an important element of an integrated pest management strategy, and studying the mechanisms of resistance is vital. It can be chemical or physical, such as oxalate crystals and other cladode characteristics. Cladode features of six cultivars (three O. ficus-indica, two O. cochenillifera, and one O. robusta) were examined for resistance to D. coccus in a completely randomized design (CRD) with three replications. ‘Rojo Pelón’ (O. ficus-indica), ‘Robusta’ (O. robusta), and ‘Bioplástico’ (O. cochinillifera) are resistant cultivars; and ‘Atlixco’ and ‘Chicomostoc’ (O. ficus-indica) and ‘Nopalea’ (O. cochinillifera) are susceptible. Cultivars showed a significant difference in cladode weight in g, cladode length, cladode width, and cladode thickness in cm, where cladode thickness was higher in ‘Rojo Pelón’ followed by ‘Robusta’. Calcium oxalates number per mm was higher in ‘Bioplástico’ (20.7+2.08) followed by ‘Robusta’ (18.9+2.31) and ‘Rojo Pelón’ (15.9+0.34); and similarly, epidermis thickness found higher in ‘Bioplástico’ (0.21+0.032) and ‘Robusta’ (0.19+0.014), but similar with ‘Rojo Pelón’ (0.18+0.026). However, cuticle thickness didn’t show a difference among cultivars. Cladode thickness, calcium oxalates number, and epidermis thickness had positive correlations with resistance. These results demonstrate that calcium oxalates number and epidermis thickness might positively affect D. coccus resistance in O. ficus-indica. This feeding-barring role and the insect-plant interaction need to be studied.

Keywords: cactus pear, resiatnce, druses, epidermis thickness

Procedia PDF Downloads 69
5555 Association among Trait Mindfulness, Leukocyte Telomere Length, and Psychological Symptoms in Singaporean Han Chinese

Authors: Shian-Ling Keng, Onn Siong Yim, Poh San Lai, Soo Chong Chew, Anne Chong, Richard Ebstein

Abstract:

Research has demonstrated a positive association between mindfulness meditation and physical health. Little work, however, has examined the association between trait mindfulness and leukocyte telomere length (LTL), an emerging marker of cellular aging. The present study aimed to examine whether facets of trait mindfulness are correlated with longer LTL in a Singaporean Han Chinese sample and whether these facets may mediate the association between psychological symptoms and LTL. 158 adults (mean age = 27.24 years) completed measures assessing trait mindfulness and psychological symptoms (i.e., depression and stress) and provided blood samples for analyses of LTL using qPCR. Multiple regression analyses were conducted to assess the association between facets of trait mindfulness and LTL. Bootstrapping-based mediational analyses were run to examine the role of trait mindfulness as a mediator of the association between psychological symptoms and LTL. Of five facets of trait mindfulness (describe, act with awareness, observe, nonreactivity, and nonjudging), nonreactivity was significantly associated with LTL, after controlling for the effects of age, gender, and education, β = .21, p = .006. Further, there was a trend for overall trait mindfulness, β = .15, p = .06, and nonjudging, β = .13, p = .095, to each predict longer LTL. Nonreactivity significantly mediated the association between depression and LTL, BCa 95% CI [-.004, -.0004], p=.03, as well as the association between stress and LTL, BCa 95% CI [-.004, -.0004], p=.04. The results provide preliminary evidence for a positive association between selected facets of trait mindfulness and slower cellular aging, indexed by LTL. The findings suggest that individuals who are high on equanimity may experience slower aging at the cellular level, presumably through engaging in more effective coping mechanisms and modulation of stress. The findings also highlight the role of nonreactivity as a potential mechanism that underlies the association between LTL and psychological symptoms.

Keywords: depression, mindfulness, stress, telomere length

Procedia PDF Downloads 339
5554 Recycled Asphalt Pavement with Warm Mix Additive for Sustainable Road Construction

Authors: Meor Othman Hamzah, Lillian Gungat, Nur Izzi Md. Yusoff, Jan Valentin

Abstract:

The recent hike in raw materials costs and the quest for preservation of the environment has prompted asphalt industries to adopt greener road construction technology. This paper presents a study on such technology by means of asphalt recycling and use of warm mix asphalt (WMA) additive. It evaluates the effects of a WMA named RH-WMA on binder rheological properties and asphalt mixture performance. The recycled asphalt, obtained from local roads, was processed, fractionated, and incorporated with virgin aggregate and binder. For binder testing, the recycled asphalt was extracted and blended with virgin binder. The binder and mixtures specimen containing 30 % and 50 % recycled asphalt contents were mixed with 3 % RH-WMA. The rheological properties of the binder were evaluated based on fundamental, viscosity, and frequency sweep tests. Indirect tensile strength and resilient modulus tests were carried out to assess the mixture’s performances. The rheological properties and strength performance results showed that the addition of RH-WMA slightly reduced the binder and mixtures stiffness. The percentage of recycled asphalt increased the stiffness of binder and mixture, and thus improves the resistance to rutting. Therefore, the integration of recycled asphalt and RH-WMA can be an alternative material for road sustainable construction for countries in the tropics.

Keywords: recycled asphalt, warm mix additive, rheological, mixture performance

Procedia PDF Downloads 511
5553 Mining User-Generated Contents to Detect Service Failures with Topic Model

Authors: Kyung Bae Park, Sung Ho Ha

Abstract:

Online user-generated contents (UGC) significantly change the way customers behave (e.g., shop, travel), and a pressing need to handle the overwhelmingly plethora amount of various UGC is one of the paramount issues for management. However, a current approach (e.g., sentiment analysis) is often ineffective for leveraging textual information to detect the problems or issues that a certain management suffers from. In this paper, we employ text mining of Latent Dirichlet Allocation (LDA) on a popular online review site dedicated to complaint from users. We find that the employed LDA efficiently detects customer complaints, and a further inspection with the visualization technique is effective to categorize the problems or issues. As such, management can identify the issues at stake and prioritize them accordingly in a timely manner given the limited amount of resources. The findings provide managerial insights into how analytics on social media can help maintain and improve their reputation management. Our interdisciplinary approach also highlights several insights by applying machine learning techniques in marketing research domain. On a broader technical note, this paper illustrates the details of how to implement LDA in R program from a beginning (data collection in R) to an end (LDA analysis in R) since the instruction is still largely undocumented. In this regard, it will help lower the boundary for interdisciplinary researcher to conduct related research.

Keywords: latent dirichlet allocation, R program, text mining, topic model, user generated contents, visualization

Procedia PDF Downloads 184
5552 Educational Reforms in Algeria: Dilemmas of Globalization, Equity, and Decolonization

Authors: Fella Lahmar

Abstract:

This chapter investigates the educational reforms in Algeria, highlighting the challenges and complexities that arise in the context of globalization, equity, and decolonization. While Algeria’s education system historically had a socialist-economic model grounded in Islamic values, contemporary reforms reflect global influences and aspirations for cultural authenticity. The study employed a qualitative approach, utilizing semi-structured interviews with a diverse sample of 15 participants intimately involved in the Algerian education system. Analysis of the data reveals a discrepancy between the educational system’s pedagogical practices and students’ diverse learning needs, implying ramifications for educational equity and social justice. Furthermore, a critical tension was evident between global influences, local cultural authenticity, and the endeavor to decolonize education. In conclusion, the chapter advocates for reforms that prioritize the students’ holistic development and well-being while fostering intrinsic motivation and engagement. This entails re-evaluating curriculum frameworks, assessment strategies, and pedagogies in light of Algeria’s cultural and religious heritage. The chapter also calls for future research to explore methods for innovatively integrating cultural heritage into education in ways to cultivate learners who are both locally grounded and globally aware.

Keywords: impact of globalization on education, parental involvement in education, marketization of education, policy enactment and reform, curriculum overload, holistic approach, shadow education

Procedia PDF Downloads 86
5551 Geochemical Characterization of Bou Dabbous Formation in Thrust Belt Zones, Northern Tunisia

Authors: M. Ben Jrad, A. Belhaj Mohamed, S. Riahi, I. Bouazizi, M. Saidi, M. Soussi

Abstract:

The generative potential, depositional environment, thermal maturity and oil seeps of the organic-rich Bou Dabbous Formation (Ypresian) from the thrust belt northwestern Tunisia, were determined by Rock Eval and molecular analyses. The paleo-tectonic units in the area show some similarities with equivalent facies in Mediterranean Sea and Sicilian. The Bou Dabbous Formation displays variable source rock characteristics through the various units Tellian and Numidian nappes Units. Organic matter contents and petroleum potentials are fair to high (reaching 1.95% and 6 kg of HC/t of rock respectively) marine type II kerogen. An increasing SE-NW maturity gradient is well documented in the study area. The Bou Dabbous organic-rich facies are marginally mature stage in the Tellian Unit (Kasseb domain), whilst they are mature-late mature stage within Nefza-Ain Allega tectonic windows. A long and north of Cap Serrat-Ghardimaou Master Fault these facies are overmature. Oil/Oil and Oil/source rock correlation, based on biomarker and carbon isotopic composition, shows a positive genetic correlation between the oil seeps and Bou Dabbous source rock.

Keywords: biomarkers, Bou Dabbous Formation, Northern Tunisia, source rock

Procedia PDF Downloads 481
5550 Using Reading to Learn Pedagogy to Promote Chinese Written Vocabulary Acquisition: An Evaluative Study

Authors: Mengping Cheng, John Everatt, Alison Arrow, Amanda Denston

Abstract:

Based on the available evidence, Chinese heritage language learners have a basic level of Chinese language proficiency with lower capability in literacy compared to speaking. Low levels of literacy are likely related to the lack of reading activities in current textbook-based pedagogy used in Chinese community schools. The present study aims to use Reading to Learn pedagogy which is a top-down language learning model and test the effectiveness of Reading to Learn on Chinese heritage learners’ written vocabulary acquisition. A quasi-experiment with the pre-test/post-test non-equivalent group design was conducted. The experimental group received Reading to Learn instructions and the control group had traditional textbook-based instructions. Participants were given Chinese characters tasks (a recognize-and-read task and a listen-and-point task), vocabulary tasks (a receptive vocabulary task and a productive vocabulary task) and a sentence cloze test in pre-tests and post-tests. Data collection is in progress and results will be available shortly. If the results show more improvement of Chinese written vocabulary in the experimental group than in the control group, it will be recommended that Reading to Learn pedagogy is valuable to be used to maintain and develop Chinese heritage language literacy.

Keywords: Chinese heritage language, experimental research, Reading to Learn pedagogy, vocabulary acquisition

Procedia PDF Downloads 146
5549 Active Thermography Technique for High-Entropy Alloy Characterization Deposited with Cold Spray Technique

Authors: Nazanin Sheibanian, Raffaella Sesana, Sedat Ozbilen

Abstract:

In recent years, high-entropy alloys (HEAs) have attracted considerable attention due to their unique properties and potential applications. In this study, novel HEA coatings were prepared on Mg substrates using mechanically alloyed HEA powder feedstocks based on Al_(0.1-0.5)CoCrCuFeNi and MnCoCrCuFeNi multi-material systems. The coatings were deposited by the Cold Spray (CS) process using three different temperatures of the process gas (N2) (650°C, 750°C, and 850°C) to examine the effect of gas temperature on coating properties. In this study, Infrared Thermography (non-destructive) was examined as a possible quality control technique for HEA coatings applied to magnesium substrates. Active Thermography was employed to characterize coating properties using the thermal response of the coating. Various HEA chemical compositions and deposition temperatures have been investigated. As a part of this study, a comprehensive macro and microstructural analysis of Cold Spray (CS) HEA coatings has been conducted using macrophotography, optical microscopy, scanning electron microscopy with energy-dispersive X-ray spectroscopy (SEM+EDS), X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), microhardness tests, roughness measurements, and porosity assessments. These analyses provided insight into phase identification, microstructure characterization, deposition, particle deformation behavior, bonding mechanisms, and identifying a possible relationship between physical properties and thermal responses. Based on the figures and tables, it is evident that the Maximum Relative Radiance (∆RMax) of each sample differs depending on both the chemical composition of HEA and the temperature at which Cold Spray is applied.

Keywords: active thermography, coating, cold spray, high- entropy alloy, material characterization

Procedia PDF Downloads 68
5548 Digitizing Masterpieces in Italian Museums: Techniques, Challenges and Consequences from Giotto to Caravaggio

Authors: Ginevra Addis

Abstract:

The possibility of reproducing physical artifacts in a digital format is one of the opportunities offered by the technological advancements in information and communication most frequently promoted by museums. Indeed, the study and conservation of our cultural heritage have seen significant advancement due to the three-dimensional acquisition and modeling technology. A variety of laser scanning systems has been developed, based either on optical triangulation or on time-of-flight measurement, capable of producing digital 3D images of complex structures with high resolution and accuracy. It is necessary, however, to explore the challenges and opportunities that this practice brings within museums. The purpose of this paper is to understand what change is introduced by digital techniques in those museums that are hosting digital masterpieces. The methodology used will investigate three distinguished Italian exhibitions, related to the territory of Milan, trying to analyze the following issues about museum practices: 1) how digitizing art masterpieces increases the number of visitors; 2) what the need that calls for the digitization of artworks; 3) which techniques are most used; 4) what the setting is; 5) the consequences of a non-publication of hard copies of catalogues; 6) envision of these practices in the future. Findings will show how interconnection plays an important role in rebuilding a collection spread all over the world. Secondly how digital artwork duplication and extension of reality entail new forms of accessibility. Thirdly, that collection and preservation through digitization of images have both a social and educational mission. Fourthly, that convergence of the properties of different media (such as web, radio) is key to encourage people to get actively involved in digital exhibitions. The present analysis will suggest further research that should create museum models and interaction spaces that act as catalysts for innovation.

Keywords: digital masterpieces, education, interconnection, Italian museums, preservation

Procedia PDF Downloads 172
5547 Biofuel Production via Thermal Cracking of Castor Methyl Ester

Authors: Roghaieh Parvizsedghy, Seyed Mojtaba Sadrameli

Abstract:

Diminishing oil reserves, deteriorating health standards because of greenhouse gas emissions and associated environmental impacts have emerged biofuel production. Vegetable oils are proved to be valuable feedstock in these growing industries as they are renewable and potentially inexhaustible sources. Thermal Cracking of vegetable oils (triglycerides) leads to production of biofuels which are similar to fossil fuels in terms of composition but their combustion and physical properties have limits. Acrolein (very poisonous gas) and water production during cracking of triglycerides occurs because of presence of glycerin in their molecular structure. Transesterification of vegetable oil is a method to extract glycerol from triglycerides structure and produce methyl ester. In this study, castor methyl ester was used for thermal cracking in order to survey the efficiency of this method to produce bio-gasoline and bio-diesel. Thus, several experiments were designed by means of central composite method. Statistical studies showed that two reaction parameters, namely cracking temperature and feed flowrate, affect products yield significantly. At the optimized conditions (480 °C and 29 g/h) for maximum bio-gasoline production, 88.6% bio-oil was achieved which was distilled and separated as bio-gasoline (28%) and bio-diesel (48.2%). Bio-gasoline exposed a high octane number and combustion heat. Distillation curve and Reid vapor pressure of bio-gasoline fell in the criteria of standard gasoline (class AA) by ASTM D4814. Bio-diesel was compatible with standard diesel by ASTM D975. Water production was negligible and no evidence of acrolein production was distinguished. Therefore, thermal cracking of castor methyl ester could be used as a method to produce valuable biofuels.

Keywords: bio-diesel, bio-gasoline, castor methyl ester, thermal cracking, transesterification

Procedia PDF Downloads 236
5546 Open Circuit MPPT Control Implemented for PV Water Pumping System

Authors: Rabiaa Gammoudi, Najet Rebei, Othman Hasnaoui

Abstract:

Photovoltaic systems use different techniques for tracking the Maximum Power Point (MPPT) to provide the highest possible power to the load regardless of the climatic conditions variation. In this paper, the proposed method is the Open Circuit (OC) method with sudden and random variations of insolation. The simulation results of the water pumping system controlled by OC method are validated by an experimental experience in real-time using a test bench composed by a centrifugal pump powered by a PVG via a boost chopper for the adaptation between the source and the load. The output of the DC/DC converter supplies the motor pump LOWARA type, assembly by means of a DC/AC inverter. The control part is provided by a computer incorporating a card DS1104 running environment Matlab/Simulink for visualization and data acquisition. These results show clearly the effectiveness of our control with a very good performance. The results obtained show the usefulness of the developed algorithm in solving the problem of degradation of PVG performance depending on the variation of climatic factors with a very good yield.

Keywords: PVWPS (PV Water Pumping System), maximum power point tracking (MPPT), open circuit method (OC), boost converter, DC/AC inverter

Procedia PDF Downloads 448
5545 Long-Term Deformations of Concrete Structures

Authors: Abdelmalk Brahma

Abstract:

Drying is a phenomenon that accompanies the hardening of hydraulic materials. It can, if it is not prevented, lead to significant spontaneous dimensional variations, which the cracking is one of events. In this context, cracking promotes the transport of aggressive agents in the material, which can affect the durability of concrete structures. Drying shrinkage develops over a long period almost 30 years although most occurred during the first three years. Drying shrinkage stabilizes when the material is water balance with the external environment. The drying shrinkage of cementitious materials is due to the formation of capillary tensions in the pores of the material, which has the consequences of bringing the solid walls of each other. Knowledge of the shrinkage characteristics of concrete is a necessary starting point in the design of structures for crack control. Such knowledge will enable the designer to estimate the probable shrinkage movement in reinforced or prestressed concrete and the appropriate steps can be taken in design to accommodate this movement. This study is concerned the modelling of drying shrinkage of the hydraulic materials and the prediction of the rate of spontaneous deformations of hydraulic materials during hardening. The model developed takes in consideration the main factors affecting drying shrinkage. There was agreement between drying shrinkage predicted by the developed model and experimental results. In last we show that developed model describe the evolution of the drying shrinkage of high performances concretes correctly.

Keywords: drying, hydraulic concretes, shrinkage, modeling, prediction

Procedia PDF Downloads 258
5544 User-Driven Product Line Engineering for Assembling Large Families of Software

Authors: Zhaopeng Xuan, Yuan Bian, C. Cailleaux, Jing Qin, S. Traore

Abstract:

Traditional software engineering allows engineers to propose to their clients multiple specialized software distributions assembled from a shared set of software assets. The management of these assets however requires a trade-off between client satisfaction and software engineering process. Clients have more and more difficult to find a distribution or components based on their needs from all of distributed repositories. This paper proposes a software engineering for a user-driven software product line in which engineers define a feature model but users drive the actual software distribution on demand. This approach makes the user become final actor as a release manager in software engineering process, increasing user product satisfaction and simplifying user operations to find required components. In addition, it provides a way for engineers to manage and assembly large software families. As a proof of concept, a user-driven software product line is implemented for eclipse, an integrated development environment. An eclipse feature model is defined, which is exposed to users on a cloud-based built platform from which clients can download individualized Eclipse distributions.

Keywords: software product line, model-driven development, reverse engineering and refactoring, agile method

Procedia PDF Downloads 428
5543 An Analysis on Gravel of Sand-Gravel Bar at Gneiss or Granite Area of the Upper Hongcheon River in South Korea

Authors: Man Kyu Kim, Hansu Shin

Abstract:

This study is an analysis on gravel of sand-gravel bar that stretches variously in the Duchon and Naechon stream basins, which are situated on Hong-Cheon River (a well-developed sand-gravel bar in upstream river) basins in Korea. Naechon stream mostly flows through granite zone but Duchon stream mostly flows through gneiss zone. The characteristics of gravel in the sand-gravel bar of these two branches in the upper Hongcheon River were analyzed in this study in order to understand the geomorphic development of streams depending on the differences of bedrock. Through the analysis on the roundness and flatness of gravel, we figured out an irregular trend following the increase in supply of granite gravel and gneiss gravel as we traveled downstream. The result shows that the two basins have uppermost small basin condition reflecting the mountain valley environment although it may be difficult to do an equivalent comparison to other roundness researches in Korea or in Europe. This study conducted an analysis on gravels found in small scale streams unlike the previous studies trend which mostly studies large rivers. The research provides an opportunity to offer basic data for continuous comparison research on various small basins.

Keywords: flatness, geology, roundness, sand-gravel bar

Procedia PDF Downloads 357
5542 Text as Reader Device Improving Subjectivity on the Role of Attestation between Interpretative Semiotics and Discursive Linguistics

Authors: Marco Castagna

Abstract:

Proposed paper is aimed to inquire about the relation between text and reader, focusing on the concept of ‘attestation’. Indeed, despite being widely accepted in semiotic research, even today the concept of text remains uncertainly defined. So, it seems to be undeniable that what is called ‘text’ offers an image of internal cohesion and coherence, that makes it possible to analyze it as an object. Nevertheless, this same object remains problematic when it is pragmatically activated by the act of reading. In fact, as for the T.A.R:D.I.S., that is the unique space-temporal vehicle used by the well-known BBC character Doctor Who in his adventures, every text appears to its own readers not only “bigger inside than outside”, but also offering spaces that change according to the different traveller standing in it. In a few words, as everyone knows, this singular condition raises the questions about the gnosiological relation between text and reader. How can a text be considered the ‘same’, even if it can be read in different ways by different subjects? How can readers can be previously provided with knowledge required for ‘understanding’ a text, but at the same time learning something more from it? In order to explain this singular condition it seems useful to start thinking about text as a device more than an object. In other words, this unique status is more clearly understandable when ‘text’ ceases to be considered as a box designed to move meaning from a sender to a recipient (marking the semiotic priority of the “code”) and it starts to be recognized as performative meaning hypothesis, that is discursively configured by one or more forms and empirically perceivable by means of one or more substances. Thus, a text appears as a “semantic hanger”, potentially offered to the “unending deferral of interpretant", and from time to time fixed as “instance of Discourse”. In this perspective, every reading can be considered as an answer to the continuous request for confirming or denying the meaning configuration (the meaning hypothesis) expressed by text. Finally, ‘attestation’ is exactly what regulates this dynamic of request and answer, through which the reader is able to confirm his previous hypothesis on reality or maybe acquire some new ones.Proposed paper is aimed to inquire about the relation between text and reader, focusing on the concept of ‘attestation’. Indeed, despite being widely accepted in semiotic research, even today the concept of text remains uncertainly defined. So, it seems to be undeniable that what is called ‘text’ offers an image of internal cohesion and coherence, that makes it possible to analyze it as an object. Nevertheless, this same object remains problematic when it is pragmatically activated by the act of reading. In fact, as for the T.A.R:D.I.S., that is the unique space-temporal vehicle used by the well-known BBC character Doctor Who in his adventures, every text appears to its own readers not only “bigger inside than outside”, but also offering spaces that change according to the different traveller standing in it. In a few words, as everyone knows, this singular condition raises the questions about the gnosiological relation between text and reader. How can a text be considered the ‘same’, even if it can be read in different ways by different subjects? How can readers can be previously provided with knowledge required for ‘understanding’ a text, but at the same time learning something more from it? In order to explain this singular condition it seems useful to start thinking about text as a device more than an object. In other words, this unique status is more clearly understandable when ‘text’ ceases to be considered as a box designed to move meaning from a sender to a recipient (marking the semiotic priority of the “code”) and it starts to be recognized as performative meaning hypothesis, that is discursively configured by one or more forms and empirically perceivable by means of one or more substances. Thus, a text appears as a “semantic hanger”, potentially offered to the “unending deferral of interpretant", and from time to time fixed as “instance of Discourse”. In this perspective, every reading can be considered as an answer to the continuous request for confirming or denying the meaning configuration (the meaning hypothesis) expressed by text. Finally, ‘attestation’ is exactly what regulates this dynamic of request and answer, through which the reader is able to confirm his previous hypothesis on reality or maybe acquire some new ones.

Keywords: attestation, meaning, reader, text

Procedia PDF Downloads 232
5541 Selection of Landscape Plant Species: A Experiment of Noise Reduction by Vibration of Plant Leaves

Authors: Li Mengmeng, Kang Jian

Abstract:

With the rapid development of the city, the noise pollution becomes more and more serious. Noise has seriously affected people's normal life, study and work. In addition, noise has seriously affected the city's ecological environment and the migration of birds. Therefore, it is urgent to control the noise. As one of natural noise-reducing materials, plants have been paid more and more attention. In urban landscape design, it is very important to choose plant species with good noise reduction effect to the sustainable development of urban ecology. The aim of this paper is to find out the characteristics of the plant with good noise reduction effect and apply it in urban landscape design. This study investigated the vibration of leaves of six plant species in a sound field using a Keyence (IG-1000/CCD) Laser Micrometer. The results of the experiments showed that the vibration speed of plant leaves increased obviously after being stimulated by sound source, about 5-10 times. In addition, when driven by the same sound, the speed of all leaves varied with the difference of leaf thickness, leaf size and leaf mass. The speed of all leaves would increase with the increase of leaf size and leaf mass, while those would decrease with the increase of leaf thickness.

Keywords: landscape design, leaf vibration , noise attenuation, plants configuration

Procedia PDF Downloads 220