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2978 Investigation of Internal Gettering at Low Temperatures of Metallic Elements in HEM Wafers mc-Si for Photovoltaic Solar Cells
Authors: Abdelghani Boucheham, Djoudi Bouhafs, Nabil Khelifati, Baya Palahouane
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The main aim of this study is to investigate the low temperature internal gettering of manganese and chromium transition metals content in p-type multicrystalline silicon grown by Heat Exchanger Method (HEM). The minority carrier lifetime variation, the transition metal elements behavior, the sheet resistivity and the interstitial oxygen concentration after different temperatures annealing under N2 ambient were investigated using quasi-steady state photoconductance technique (QSSPC), secondary ion mass spectroscopy (SIMS), four-probe measurement and Fourier transform infrared spectrometer (FTIR), respectively. The obtained results indicate in the temperature range of 300°C to 700°C that the effective lifetime increases and reaches its maximum values of 28 μs at 500 °C and decreasing to 6 μs at 700 °C. This amelioration is due probably to metallic impurities internal gettering in the extended defects and in the oxygen precipitates as observed on SIMS profiles and the FTIR spectra. From 300 °C to 500 °C the sheet resistivity values rest unchanged at 30 Ohm/sq and rises significantly to reach 45 Ohm/sq for T> 500 °C.Keywords: mc-Si, low temperature annealing, internal gettering, minority carrier lifetime, interstitial oxygen, resistivity
Procedia PDF Downloads 3082977 Preparation of Alumina (Al2O3) Particles and MMCS of (Al-7% Si– 0.45% Mg) Alloy Using Vortex Method
Authors: Abdulmagid A. Khattabi
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The aim of this research is to study the manner of alumina (Al2O3) particles dispersion with (2-10) mm size in (Al-7%Si-0.45% Mg) base of alloy melt employing of classical casting method. The mechanism of particles diffusions by melt turning and stirring that makes vortexes help the particles entrance in the matrix of base alloy also has been studied. The samples of metallic composites (MMCs) with dispersed particles percentages (4% - 6% - 8% - 10% - 15% and 20%) are prepared. The effect of the particles dispersion on the mechanical properties of produced samples were carried out by tension & hardness tests. It is found that the ultimate tensile strength of the produced composites can be increased by increasing the percentages of alumina particles in the matrix of the base alloy. It becomes (232 Mpa) at (20%) of added particles. The results showed that the average hardness of prepared samples increasing with increases the alumina content. Microstructure study of prepared samples was carried out. The results showed particles location and distribution of it in the matrix of base alloy. The dissolution of Alumina particles into liquid base alloy was clear in some cases.Keywords: base alloy, matrix, hardness, thermal properties, base metal MMCs
Procedia PDF Downloads 3542976 Study of Interaction between Recycled Asphalt Pavement (RAP) Material and Virgin Material
Authors: G. Bharath, K. S. Reddy, Vivek Tandon, M. Amaranatha Reddy
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This paper presents the details of a study conducted to evaluate the interaction between recycled binder and fresh binder in Recycled Asphalt Pavement (RAP) mixes. When RAP is mixed with virgin aggregates in the presence of fresh binder there will be partial blending in a hot mix asphalt mixture. A recent approach used by some researchers for studying the degree of blending of RAP binder with virgin binder has been adopted in this study. Dense Bituminous Macadam mix of Ministry of Road Transport of India with a nominal maximum aggregate size of 19 mm was studied. Two proportions of RAP-20% and 35% and two types of virgin binders – viscosity grade VG10 and VG30 were considered. Design binder contents were determined for all the four types of mixes (two RAP contents and two virgin binders) as per Marshall mix design procedure. The degree of blending of RAP and virgin binders was evaluated in terms of the complex modulus of the binder. Laboratory test results showed that with an increase in RAP content, the degree of blending decreases. Better blending was observed for softer grade binder (VG10).Keywords: blending, complex modulus, recycled asphalt pavement, virgin binder
Procedia PDF Downloads 4322975 Empowering the Sustainability of Community Health: An Application of the Theory of Maqasid Al-Shariah
Authors: Ahasanul Haque, Noor Hazilah Abd Manaf, Zohurul Anis, Tarekol Islam
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Sustainable community health (SCH) is an example of a new healthcare concept formed from applying the Maqasid al-Shariah principle to hospital management and delivery services. Because the idea is novel, it needs comprehensive and ongoing investigation to be improved. However, there is a lack of research on the necessity of developing sustainable community health (SCH), particularly its organizational structure. Furthermore, there is a misconception about the order of components in Maqasid al-Shariah, particularly in a hospital setting. Furthermore, the use of medicines and treatment by conventional recommendations to carry out the treatment by the Maqasid al Shariah. As such, this study focuses on the essential prerequisite for establishing a sustainable community health system based on Maqasid al-Shariah. This study discusses the use of Maqasid al-Shariah in administration and treatment. In this qualitative research approach, a literature search and interviews with specialists are conducted. The gathered data is examined using content analysis, emphasizing inductive and deductive reasoning. The research reveals that the Shariah Advisory Council and Shariah Critical Point are necessary for sustainable community health. In conclusion, by discussing the causes for each instance, this research adds to the creation of methods for determining the level of Maasid al-Shariah in-hospital care.Keywords: empowering, sustainability, community health, maqasid al shariah, hospital and malaysia
Procedia PDF Downloads 842974 Texture Characteristics and Depositional Environment of the Lower Mahi River Sediment, Mainland Gujarat, India
Authors: Shazi Farooqui, Anupam Sharma
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The Mahi River (~600km long) is an important west flowing the river of Central India. It originates in Madhya Pradesh and starts flowing in NW direction and enters into the state of Rajasthan. It flows across southern Rajasthan and then enters into Gujarat and finally debouches in the Gulf of Cambay. In Gujarat state, it flows through all four geomorphic zones i.e. eastern upland zone, shallow buried piedmont zone, alluvial zone and coastal zone. In lower reaches and particularly when it is flowing under the coastal regime, it provides an opportunity to study – 1. Land–Sea interaction and role of relative sea level changes, 2. Coastal/estuarine geological process, 3. Landscape evolution in marginal areas and so on. The Late Quaternary deposits of Mainland Gujarat is appreciably studied by Chamyal and his group of MS University of Baroda, and they have established that the 30-35m thick sediment package of the Mainland Gujarat is comprised of marine, fluvial and aeolian sediments. It is also established that in the estuarine zone, the upper few meter thick sediments package is of marine nature. However, its thickness, characters and the depositional environment including the role of climate and tectonics is still not clearly defined. To understand few aspects of the above mentioned, in the present study, a 17m subsurface sediment core has been retrieved from the estuarine zone of Mahi river basin. The Multiproxy studies which include the textural analysis (grain size), Loss on ignition (LOI), Bulk and clay mineralogy and geochemical studies have been carried out. In the entire sedimentary sequence, the grain size largely varies from coarse sand to clay; however, a solitary gravel bed is also noticed. The lower part (depth 9-17m), is mainly comprised of sub equal proportion of sand and silt. The sediments mainly have bimodal and leptokurtic distribution and deposited in alternate sand-silt package, probably indicating flood deposits. Relatively low moisture (1.8%) and organic carbon (2.4%) with increased carbonate values (12%) indicate that conditions must have to remain oxidizing. The middle part (depth 9–6m) has a 1m thick gravel bed at the bottom and overlain by coarse sand to very fine sand showing fining upward sequence. The presence of gravel bed suggests some kind of tectonic activity resulting into change in base level or enhanced precipitation in the catchment region. The upper part (depth 6–0m; top part of sequence) mainly comprised of fine sand to silt size grains (with appreciable clay content). The sediment of this part is Unimodal and very leptokurtic in nature suggesting wave and winnowing process and deposited in low energy suspension environment. This part has relatively high moisture (2.1%) and organic carbon (2.7%) with decreased carbonate content (4.2%) indicating change in the depositional environment probably under estuarine conditions. The presence of chlorite along with smectite clay mineral further supports the significant marine contribution in the formation of upper part of the sequence.Keywords: grain size, statistical analysis, clay minerals, late quaternary, LOI
Procedia PDF Downloads 1812973 Feasibility of a Biopolymer as Lightweight Aggregate in Perlite Concrete
Authors: Ali A. Sayadi, Thomas R. Neitzert, G. Charles Clifton
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Lightweight concrete is being used in the construction industry as a building material in its own right. Ultra-lightweight concrete can be applied as a filler and support material for the manufacturing of composite building materials. This paper is about the development of a stable and reproducible ultra-lightweight concrete with the inclusion of poly-lactic acid (PLA) beads and assessing the feasibility of PLA as a lightweight aggregate that will deliver advantages such as a more eco-friendly concrete and a non-petroleum polymer aggregate. In total, sixty-three samples were prepared and the effectiveness of mineral admixture, curing conditions, water-cement ratio, PLA ratio, EPS ratio and perlite ratio on compressive strength of perlite concrete are studied. The results show that PLA particles are sensitive to alkali environment of cement paste and considerably shrank and lost their strength. A higher compressive strength and a lower density was observed when expanded polystyrene (EPS) particles replaced PLA beads. In addition, a set of equations is proposed to estimate the water-cement ratio, cement content and compressive strength of perlite concrete.Keywords: perlite concrete, poly-lactic acid (pla), expanded polystyrene (eps), concrete
Procedia PDF Downloads 3142972 Deep Learning Based Unsupervised Sport Scene Recognition and Highlights Generation
Authors: Ksenia Meshkova
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With increasing amount of multimedia data, it is very important to automate and speed up the process of obtaining meta. This process means not just recognition of some object or its movement, but recognition of the entire scene versus separate frames and having timeline segmentation as a final result. Labeling datasets is time consuming, besides, attributing characteristics to particular scenes is clearly difficult due to their nature. In this article, we will consider autoencoders application to unsupervised scene recognition and clusterization based on interpretable features. Further, we will focus on particular types of auto encoders that relevant to our study. We will take a look at the specificity of deep learning related to information theory and rate-distortion theory and describe the solutions empowering poor interpretability of deep learning in media content processing. As a conclusion, we will present the results of the work of custom framework, based on autoencoders, capable of scene recognition as was deeply studied above, with highlights generation resulted out of this recognition. We will not describe in detail the mathematical description of neural networks work but will clarify the necessary concepts and pay attention to important nuances.Keywords: neural networks, computer vision, representation learning, autoencoders
Procedia PDF Downloads 1272971 Development of a Thermodynamic Model for Ladle Metallurgy Steel Making Processes Using Factsage and Its Macro Facility
Authors: Prasenjit Singha, Ajay Kumar Shukla
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To produce high-quality steel in larger volumes, dynamic control of composition and temperature throughout the process is essential. In this paper, we developed a mass transfer model based on thermodynamics to simulate the ladle metallurgy steel-making process using FactSage and its macro facility. The overall heat and mass transfer processes consist of one equilibrium chamber, two non-equilibrium chambers, and one adiabatic reactor. The flow of material, as well as heat transfer, occurs across four interconnected unit chambers and a reactor. We used the macro programming facility of FactSage™ software to understand the thermochemical model of the secondary steel making process. In our model, we varied the oxygen content during the process and studied their effect on the composition of the final hot metal and slag. The model has been validated with respect to the plant data for the steel composition, which is similar to the ladle metallurgy steel-making process in the industry. The resulting composition profile serves as a guiding tool to optimize the process of ladle metallurgy in steel-making industries.Keywords: desulphurization, degassing, factsage, reactor
Procedia PDF Downloads 2172970 Raising Multilingual Awareness towards Plurilingual Competence Development: Through Which Approach and Which Pedagogical Material-A Case Study in the Greek Primary Education
Authors: Eftychia Damaskou
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This article intends to place the question of the adequate approach for teaching multilingualism within the public education. Linguistic education, as it is defined by the Common European Framework of Reference for the Languages, is no longer the proficiency in one or two languages. It’s about the development of a linguistic repertoire, where all linguistic skills find their place. In fact, the linguistic theories that frame the development of plurilingual competence point out the affective and intercultural aspect of such a process, insisting on an awareness of linguistic diversification, rather than an acquisition of communicative competence in many languages. In this spirit, our article attempts to go beyond a mere plurilingual awareness, present a research based on an experience in class, within 115 pupils, aiming at the development of plurilingual competence in five unknown foreign languages. This experience was held through a teaching unit personally conceived and applied, and consisted of a series of 6 activities based on a cross-linguistic content approach. The data analysis proves to be very interesting, as it reveals the development of plurilingual competences, as well as positive attitudes towards less common languages by the majority of our sample.Keywords: multilingual awareness, multilingual teaching material, plurilingual competence
Procedia PDF Downloads 4512969 Analysis of Labor Effectiveness at Green Tea Dry Sorting Workstation for Increasing Tea Factory Competitiveness
Authors: Bayu Anggara, Arita Dewi Nugrahini, Didik Purwadi
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Dry sorting workstation needs labor to produce green tea in Gambung Tea Factory. Observation results show that there is labor who are not working at the moment and doing overtime jobs to meet production targets. The measurement of the level of labor effectiveness has never been done before. The purpose of this study is to determine the level of labor effectiveness and provide recommendations for improvement based on the results of the Pareto diagram and Ishikawa diagram. The method used to measure the level of labor effectiveness is Overall Labor Effectiveness (OLE). OLE had three indicators which are availability, performance, and quality. Recommendations are made based on the results of the Pareto diagram and Ishikawa diagram for indicators that do not meet world standards. Based on the results of the study, the OLE value was 68.19%. Recommendations given to improve labor performance are adding mechanics, rescheduling rest periods, providing special training for labor, and giving rewards to labor. Furthermore, the recommendations for improving the quality of labor are procuring water content measuring devices, create material standard policies, and rescheduling rest periods.Keywords: Ishikawa diagram, labor effectiveness, OLE, Pareto diagram
Procedia PDF Downloads 2292968 Performance Evaluation of Microcontroller-Based Fuzzy Controller for Fruit Drying System
Authors: Salisu Umar
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Fruits are a seasonal crop and get spoiled quickly. They are dried to be preserved for a long period. The natural drying process requires more time. The investment on space requirement and infrastructure is large, and cannot be afforded by a middle class farmer. Therefore there is a need for a comparatively small unit with reduced drying times, which can be afforded by a middle class farmer. A controlled environment suitable for fruit drying is developed within a closed chamber and is a three step process. Firstly, the infrared light is used internally to preheated the fruit to speedily remove the water content inside the fruit for fast drying. Secondly, hot air of a specified temperature is blown inside the chamber to maintain the humidity below a specified level and exhaust the humid air of the chamber. Thirdly the microcontroller idles disconnecting the power to the chamber after the weight of the fruits is reduced to a known value of its original weight. This activates a buzzer for duration of ten seconds to indicate the end of the drying process. The results obtained indicate that the system is significantly reducing the drying time without affecting the quality of the fruits compared with the existing dryers.Keywords: fruit, fuzzy controller, microcontroller, temperature, weight and humidity
Procedia PDF Downloads 4452967 Social Media Impact on Startup Entrepreneurial Intention: Evidence from Greece
Authors: Panagiotis I. Mallios, Vassilis S. Moustakis
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The research reported herein presents a conceptual model that explores the relationship between social media factors and entrepreneurial intention, with a focus on the Greek startup ecosystem. The significance of the study is that social media have gained importance in explaining the entrepreneurial process, and through them, nascent and potential entrepreneurs seem to get inspired and motivated to initiate their businesses. The research methodology employed in this study included a qualitative research approach, utilizing in-depth interviews with a sample of 15 startup entrepreneurs providing valuable retrospective information. The data collected were analyzed using the content analysis method. The major findings of the study are that social media factors such as usefulness, influence, and credibility have a significant impact on entrepreneurial intention. We also found that social media can be a powerful tool for entrepreneurs to access resources, knowledge and networks that can help them in their venture creation. Overall, this research contributes to the entrepreneurship literature by uncovering the relationship between social media factors and entrepreneurial intention and has implications for entrepreneurial education, policymakers, and official partners, highlighting the potential of social media to enhance the startup ecosystem.Keywords: entrepreneurial intention, social media, start up ecosystem, entrepreneurship
Procedia PDF Downloads 1692966 Design Thinking and Project-Based Learning: Opportunities, Challenges, and Possibilities
Authors: Shoba Rathilal
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High unemployment rates and a shortage of experienced and qualified employees appear to be a paradox that currently plagues most countries worldwide. In a developing country like South Africa, the rate of unemployment is reported to be approximately 35%, the highest recorded globally. At the same time, a countrywide deficit in experienced and qualified potential employees is reported in South Africa, which is causing fierce rivalry among firms. Employers have reported that graduates are very rarely able to meet the demands of the job as there are gaps in their knowledge and conceptual understanding and other 21st-century competencies, attributes, and dispositions required to successfully negotiate the multiple responsibilities of employees in organizations. In addition, the rates of unemployment and suitability of graduates appear to be skewed by race and social class, the continued effects of a legacy of inequitable educational access. Higher Education in the current technologically advanced and dynamic world needs to serve as an agent of transformation, aspiring to develop graduates to be creative, flexible, critical, and with entrepreneurial acumen. This requires that higher education curricula and pedagogy require a re-envisioning of our selection, sequencing, and pacing of the learning, teaching, and assessment. At a particular Higher education Institution in South Africa, Design Thinking and Project Based learning are being adopted as two approaches that aim to enhance the student experience through the provision of a “distinctive education” that brings together disciplinary knowledge, professional engagement, technology, innovation, and entrepreneurship. Using these methodologies forces the students to solve real-time applied problems using various forms of knowledge and finding innovative solutions that can result in new products and services. The intention is to promote the development of skills for self-directed learning, facilitate the development of self-awareness, and contribute to students being active partners in the application and production of knowledge. These approaches emphasize active and collaborative learning, teamwork, conflict resolution, and problem-solving through effective integration of theory and practice. In principle, both these approaches are extremely impactful. However, at the institution in this study, the implementation of the PBL and DT was not as “smooth” as anticipated. This presentation reports on the analysis of the implementation of these two approaches within higher education curricula at a particular university in South Africa. The study adopts a qualitative case study design. Data were generated through the use of surveys, evaluation feedback at workshops, and content analysis of project reports. Data were analyzed using document analysis, content, and thematic analysis. Initial analysis shows that the forces constraining the implementation of PBL and DT range from the capacity to engage with DT and PBL, both from staff and students, educational contextual realities of higher education institutions, administrative processes, and resources. At the same time, the implementation of DT and PBL was enabled through the allocation of strategic funding and capacity development workshops. These factors, however, could not achieve maximum impact. In addition, the presentation will include recommendations on how DT and PBL could be adapted for differing contexts will be explored.Keywords: design thinking, project based learning, innovative higher education pedagogy, student and staff capacity development
Procedia PDF Downloads 772965 Adsorptive Desulfurization of Using Cu(I) – Y Zeolite via π-Complexation
Authors: Moshe Mello, Hilary Rutto, Tumisang Seodigeng, Itumeleng Kohitlhetse
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The accelerating requirement to reach 0% sulfur content in liquid fuels demand researchers to seek efficient alternative technologies to challenge the predicament. In this current study, the adsorption capabilities of modified Cu(I)-Y zeolite were tested for the removal of organosulfur compounds (OSC) present in tire pyrolytic oil (TPO). The π-complexation-based adsorbent was obtained by ion exchanging Y-zeolite with Cu+ cation using liquid phase ion exchange (LPIE). Preparation of the adsorbent involved firstly ion exchange between Na-Y zeolite with a Cu(NO₃)₂ aqueous solution of 0.5M for 48 hours followed by reduction of Cu²⁺ to Cu+. Fixed-bed breakthrough studies for TPO in comparison with model diesel comprising of sulfur compounds such as thiophene, benzothiophenes (BT), and dibenzothiophenes (DBT) showed that modified Cu(I)-Y zeolite is an effective adsorbent for removal of OSC in liquid fuels. The effect of operating conditions such as adsorbent dosage and reaction time were studied to optimize the adsorptive desulfurization process. For model diesel fuel, the selectivity for adsorption of sulfur compounds followed the order DBT> BT> Thiophene. The Cu(I)-Y zeolite is fully regeneratable and this is achieved by a simple procedure of blowing the adsorbent with air at 350 °C, followed by reactivation at 450 °C in a rich helium surrounding.Keywords: adsorption, desulfurization, TPO, zeolite
Procedia PDF Downloads 1152964 Investigating the Encouraging Factors for Scholarly Works Contribution towards Institutional Repository: A Case Study at a Malaysian University
Authors: Mohd Rashid bin Ab Hamid, Noor Azura binti Omar, Zainol Bin Mustafa
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Purpose: The aim of this paper is to study the encouraging factors for scholarly works contribution towards among academicians at Malaysian university. Methods: This paper uses questionnaire for data collection on the respondents’ perceptional level on the institutional repository efforts in one of the university under study. Several encouraging factors have been identified and to be measured using descriptive statistics. The factors are related to content contribution, i.e. personal factor, professional factor, organizational factor and technological factor. Findings: The study found that all these four encouraging factors did have a relation to the contribution of scholarly works in the university by the academician. Research Limitations: This study used a case study and generalization to all Malaysian universities should be well taken care of. Practical implications: The library at the university should look into these four encouraging factors in order to enhance the contribution from academician towards the repository. Originality/value: This research paper provides basic information for the knowledge management officers in the university by endeavouring more efforts in order to attract more contributions.Keywords: institutional repository, information retrieval, information storage and retrieval
Procedia PDF Downloads 5612963 Protecting the Privacy and Trust of VIP Users on Social Network Sites
Authors: Nidal F. Shilbayeh, Sameh T. Khuffash, Mohammad H. Allymoun, Reem Al-Saidi
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There is a real threat on the VIPs personal pages on the Social Network Sites (SNS). The real threats to these pages is violation of privacy and theft of identity through creating fake pages that exploit their names and pictures to attract the victims and spread of lies. In this paper, we propose a new secure architecture that improves the trusting and finds an effective solution to reduce fake pages and possibility of recognizing VIP pages on SNS. The proposed architecture works as a third party that is added to Facebook to provide the trust service to personal pages for VIPs. Through this mechanism, it works to ensure the real identity of the applicant through the electronic authentication of personal information by storing this information within content of their website. As a result, the significance of the proposed architecture is that it secures and provides trust to the VIPs personal pages. Furthermore, it can help to discover fake page, protect the privacy, reduce crimes of personality-theft, and increase the sense of trust and satisfaction by friends and admirers in interacting with SNS.Keywords: social network sites, online social network, privacy, trust, security and authentication
Procedia PDF Downloads 3812962 Upper Jurassic to Lower Cretaceous Oysters (Bivalvia, Ostreoidea) from Siberia: Taxonomy and Variations of Carbon and Oxygen Isotopes
Authors: Igor N. Kosenko
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The present contribution is an analysis of more than 300 specimens of Upper Jurassic to Lower Cretaceous oysters collected by V.A. Zakharov during the 1960s and currently stored in the Trofimuk Institute of Geology and Geophysics SB RAS (Novosibirsk, Russia). They were sampled in the northwestern bounder of Western Siberia (Yatriya, Maurynia, Tol’ya and Lopsiya rivers) and the north of Eastern Siberia (Boyarka, Bolshaya Romanikha and Dyabaka-Tari rivers). During the last five years, they were examined with taxonomical and palaeoecological purposes. Based on carbonate material of oyster’s shells were performed isotopic analyses and associated palaeotemperatures. Taxonomical study consists on classical morphofunctional and biometrical analyses. It is completed by another large amount of Cretaceous oysters from Crimea as well as modern Pacific oyster - Crassostrea gigas. Those were studied to understand the range of modification variability between different species. Oysters previously identified as Liostrea are attributed now to four genera: Praeexogyra and Helvetostrea (Flemingostreidae), Pernostrea (Gryphaeidae) and one new genus (Gryphaeidae), including one species “Liostrea” roemeri (Quenstedt). This last is characterized by peculiar ethology, being attached to floating ammonites and morphology, outlined by a beak-shaped umbo on the right (!) valve. Endemic Siberian species from the Pernostrea genus have been included into the subgenus Boreiodeltoideum subgen. nov. Pernostrea and Deltoideum genera have been included into the tribe Pernostreini n. trib. from the Gryphaeinae subfamily. Model of phylogenetic relationships between species of this tribe has been proposed. Siberian oyster complexes were compared with complexes from Western Europe, Poland and East European Platform. In western Boreal and Subboreal Realm (England, northern France and Poland) two stages of oyster’s development were recognized: Jurassic-type and Cretaceous-type. In Siberia, Jurassic and Lower Cretaceous oysters formed a unique complex. It may be due to the isolation of the Siberian Basin toward the West during the Early Cretaceous. Seven oyster’s shells of Pernostrea (Pernostrea) uralensis (Zakharov) from the Jurassic/Cretaceous Boundary Interval (Upper Volgian – Lower Ryazanian) of Maurynia river were used to perform δ13C and δ18O isotopic analyses. The preservation of the carbonate material was controlled by: cathodoluminescence analyses; content of Fe, Mn, Sr; absence of correlation between δ13C and δ18O and content of Fe and Mn. The obtained δ13C and δ18O data were compared with isotopic data based on belemnites from the same stratigraphical interval of the same section and were used to trace palaeotemperatures. A general trend towards negative δ18O values is recorded in the Maurynia section, from the lower part of the Upper Volgian to the middle part of the Ryazanian Chetaites sibiricus ammonite zone. This trend was previously recorded in the Nordvik section. The higher palaeotemperatures (2°C in average) determined from oyster’s shells indicate that belemnites likely migrated laterally and lived part of their lives in cooler waters. This work financially supported by the Russian Foundation for Basic Researches (grant no. 16-35-00003).Keywords: isotopes, oysters, Siberia, taxonomy
Procedia PDF Downloads 1942961 Investigation of the Field Trip Method’s Effectiveness: As a Way of Improving Pre-Service Teachers’ Views on Environmental Education
Authors: Abuzer Akgün, Ümit Duruk
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This study was carried out in a period of four weeks thanks to voluntarily participation of twenty eight pre-service teachers enrolled diverse departments in Faculty of Education. The purpose of the study was to point out how pre-service teachers views on environmental education were affected by field trips. Prior to data collection, four open-ended questions were prepared and administered to all pre-service teachers in the working group. Data gathered at first and final week of the field trip were compared in a qualitative approach using content analysis. In conclusion, it is obvious that most of the participants don’t feel themselves quiet enough about environmental education and state this reason as a providing justification to participate voluntarily in the study. In the secondary school teaching context, they mostly emphasize on the vital importance of the environmental awareness level of the pupils in the schools. They also seem to think that they get a detailed knowledge of environmental education and claim that they will use this knowledge in order to bring up next generations in their professional career as teachers. Lastly, they state that observing the deteriorating materials directly in their own settings, might be more effective as regards improving environmental awareness.Keywords: science education, environmental education, environmental issues, field trip method
Procedia PDF Downloads 3562960 Assessment of Naturally Occurring Radionuclides of the Surface Water in Vaal River, South Africa
Authors: Kgantsi B. T., Ochwelwang A. R., Mathuthu M., Jegede O. A.
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Anthropogenic activities near water bodies contribute to poor water quality, which degrades the condition of the biota and elevates the risk to human health. The Vaal River is essential in supplying Gauteng and neighboring regions of South Africa with portable water for a variety of consumers and industries. Consequently, it is necessary to monitor and assess the radioactive risk in relation to the river's water quality. This study used an inductive coupled plasma mass spectrometer (ICPMS) to analyze the radionuclide activity concentration in the Vaal River, South Africa. Along with thorium and potassium, the total uranium concentration was calculated using the isotopic content of uranium. The elemental concentration of ²³⁸U, ²³⁵U, ²³⁴U, ²³²Th, and 40K were translated into activity concentrations. To assess the water safety for all users and consumers, all values were compared to world average activity concentrations 35, 30, and 400 Bqkg⁻¹ for ²³⁸U, ²³⁴Th, and ⁴⁰K, respectively, according to the UNSCEAR report. The results will serve as a database for further monitoring and evaluation of the radionuclide from the river, taking cognisance of potential health hazards.Keywords: Val Rivers, ICPMS, uranium, risks
Procedia PDF Downloads 1632959 Kiddo: Design and Prototype of a Useable Mobile Application for Kids to Learn under Parental Control
Authors: Albandary Alamer, Noura Alaskar, Sana Bukhamseen, Jawaher Alkhamis, Enas Alghamdi, Almaha Almulhim, Hina Gull, Rachid Zagrouba, Madeeha Saqib
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A good and healthy seed will always produce a nice fruit, whereas an infected seed will produce an infected fruit. The same concept applies to the children, and the healthier the environment in which the kids grow, the more likely they become valuable members of society. Kiddo project introduces us to a mobile application that focuses on enhancing the sense of responsibility from a young age and makes raising kids fun and easy. The application aims to enhance the communication between parents and their children and to enrich the good habits of the kid. Kiddo Application enables kids to share their accomplishments with their peers in an interactive environment full of enjoyment, followed by parental monitoring to handle what their kids are posting and friends following. Kiddo provides the kids' and parents’ society with a safe platform free of cyberbullying and inappropriate content with parents' fun engagement.Keywords: kids social media, educational app, child-raising, parental control, cyberbullying, parent-child relationship, good habits
Procedia PDF Downloads 1582958 An Examination of the Relationship between Adolescents' Social Media Use and Social Appearance Anxiety
Authors: Aynur Bütün Ayhan, Utku Beyazıt
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Adolescents can be heavily influenced by social media content as they develop their identities and body images. Therefore, the intensive use of social media platforms may have important effects on their body image beliefs. In this context, the objective of the present study was to assess the relationship between adolescents' social media use and their body image concerns. The study included 265 adolescents (133 girls and 132 boys) between the ages of 15 and 17 who were attending a high school in Ankara, Türkiye. In the study, the adolescents were administered the Social Media Addiction Scale to assess their level of social media use and the Social Appearance Anxiety Scale to assess their social appearance anxiety. Prior to analysis, a normality test was applied, and it was determined that the data displayed a non-parametric distribution. As a result, a significant positive relationship (r=.322, p<.01) was found between adolescents' level of social use and social appearance anxiety. It was also determined that social media addiction and social appearance anxiety significantly differed (p<.05) according to adolescents' opinions about their own bodies, being influenced by body images they see on social media and weight perceptions. The findings suggest that social media use should be managed carefully for adolescents to develop a healthy body image.Keywords: social media, adolescent, social appearence, anxiety
Procedia PDF Downloads 232957 Recovery of Dredged Sediments With Lime or Cement as Platform Materials for Use in a Roadway
Authors: Abriak Yassine, Zri Abdeljalil, Benzerzour Mahfoud., Hadj Sadok Rachid, Abriak Nor-Edine
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In this study, firstly, the study of the capacity reuse of dredged sediments and treated sediments with lime or cement were used in an establishment layer and the base layer of the roadway. Also, the analysis of mineral changes caused by the addition of lime or cement on the way as described in the mechanical results of stabilised sediments. After determining the quantity of lime and cement required to stabilise the sediment, the compaction characteristics were studied using the modified Proctor method. Then the evolution of the three parameters, that is, ideal water content and maximum dry density had been determined. Mechanical exhibitions can be assessed across the resistance to compression, flexibility modulus and the resistance under traction. The resistance of the formulation treated with cement addition (ROLAC®645) increase with the quantity of ROLAC®645. Traction resistances and the elastic modulus were utilized to assess the potential of the formulation as road construction materials utilizing classification diagram. The results show the various formulations with ROLAC® 645may be employed in subgrades and foundation layers for roads.Keywords: cement, dredged, sediment, foundation layer, resistance
Procedia PDF Downloads 992956 Enriching Interaction in the Classroom Based on Typologies of Experiments and Mathematization in Physics Teaching
Authors: Olga Castiblanco, Diego Vizcaíno
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Changing the traditional way of using experimentation in science teaching is quite a challenge. This research results talk about the characterization of physics experiments, not because of the topic it deals with, nor depending on the material used in the assemblies, but related to the possibilities it offers to enrich interaction in the classroom and thereby contribute to the development of scientific thinking skills. It is an action-research of type intervention in the classroom, with four courses of Physics Teaching undergraduate students from a public university in Bogotá. This process allows characterizing typologies such as discrepant, homemade, illustrative, research, recreational, crucial, mental, and virtual experiments. Students' production and researchers' reports on each class were the most relevant data. Content analysis techniques let to categorize the information and obtain results on the richness that each typology of experiment offers when interacting in the classroom. Results show changes in the comprehension of new teachers' role, far from being the possessor and transmitter of the truth. Besides, they understand strategies to engage students effectively since the class advances extending ideas, reflections, debates, and questions, either towards themselves, their classmates, or the teacher.Keywords: physics teacher training, non-traditional experimentation, contextualized education, didactics of physics
Procedia PDF Downloads 952955 Chemopreventive Properties of Cannabis sativa L. var. USO31 in Relation to Its Phenolic and Terpenoid Content
Authors: Antonella Di Sotto, Cinzia Ingallina, Caterina Fraschetti, Simone Circi, Marcello Locatelli, Simone Carradori, Gabriela Mazzanti, Luisa Mannina, Silvia Di Giacomo
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Cannabis sativa L. is one of the oldest cultivated plant species known not only for its voluptuous use but also for the wide application in food, textile, and therapeutic industries. Recently, the progress of biotechnologies applied to medicinal plants has allowed to produce different hemp varieties with low content of psychotropic phytoconstituents (tetrahydrocannabinol < 0.2% w/v), thus leading to a renewed industrial and therapeutic interest for this plant. In this context, in order to discover new potential remedies of pharmaceutical and/or nutraceutical interest, the chemopreventive properties of different organic and hydroalcoholic extracts, obtained from the inflorescences of C. sativa L. var. USO31, collected in June and September harvesting, were assessed. Particularly, the antimutagenic activity towards the oxidative DNA-damage induced by tert-butyl hydroperoxide (t-BOOH) was evaluated, and the DPPH (2,2-diphenyl-1-picrylhydrazyl) and ABTS (2,2'-azino-bis-3-ethylbenzthiazoline-6-sulphonic acid) radical scavenging power of the samples were assessed as possible mechanisms of antimutagenicity. Furthermore, the ability of the extracts to inhibit the glucose-6-phosphate dehydrogenase (G6PD), whose overexpression has been found to play a critical role in neoplastic transformation and tumor progression, has been studied as a possible chemopreventive strategy. A careful phytochemical characterization of the extracts for phenolic and terpenoid composition has been obtained by high performance liquid chromatography (HPLC) and gas chromatography-mass spectrometry (GC-MS) methods. Under our experimental condition, all the extracts were found able to interfere with the tBOOH-induced mutagenicity in WP2uvrAR strain, although with different potency and effectiveness. The organic extracts from both the harvesting periods were found to be the main effective antimutagenic samples, reaching about a 55% inhibition of the tBOOH-mutagenicity at the highest concentration tested (250 μg/ml). All the extracts exhibited radical scavenger activity against DPPH and ABTS radicals, with a higher potency of the hydroalcoholic samples. The organic extracts were also able to inhibit the G6PD enzyme, being the samples from September harvesting the highly potent (about 50% inhibition respect to the vehicle). At the phytochemical analysis, all the extracts resulted to contain both polar and apolar phenolic compounds. The HPLC analysis revealed the presence of catechin and rutin as the major constituents of the hydroalcoholic extracts, with lower levels of quercetin and ferulic acid. The monoterpene carvacrol was found to be an ubiquitarian constituent. At GC-MS analysis, different terpenoids, among which caryophyllene sesquiterpenes, were identified. This evidence suggests a possible role of both polyphenols and terpenoids in the chemopreventive properties of the extracts from the inflorescences of C. sativa var. USO31. According to the literature, carvacrol and caryophyllene sesquiterpenes can contribute to the strong antimutagenicity although the role of all the hemp phytocomplex cannot be excluded. In conclusion, present results highlight a possible interest for the inflorescences of C. sativa var. USO31 as source of bioactive molecules and stimulate further studies in order to characterize its possible application for nutraceutical and pharmaceutical purposes.Keywords: antimutagenicity, glucose-6-phosphate dehydrogenase, hemp inflorescences, nutraceuticals, sesquiterpenes
Procedia PDF Downloads 1572954 New Chances of Reforming Pedagogical Approach In Secondary English Class in China under the New English Curriculum and National College Entrance Examination Reform
Authors: Yue Wang
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Five years passed since the newest English curriculum reform policy was published in China, hand-wringing spread among teachers who accused that this is another 'Wearing New Shoes to Walk the Old Road' policy. This paper provides a thoroughly philosophical policy analysis of serious efforts that had been made to support this reform and reveals the hindrances that bridled the reform to yield the desired effect. Blame could be easily put on teachers for their insufficient pedagogical content knowledge, conservative resistance, and the handicaps of large class sizes and limited teaching times, and so on. However, the underlying causes for this implementation failure are the interrelated factors in the NCEE-centred education system, such as the reluctant from students, the lack of school and education bureau support, and insufficient teacher training. A further discussion of 2017 to 2020’s NCEE reform on English prompt new possibilities for the authentic pedagogical approach reform in secondary English classes. In all, the pedagogical approach reform at the secondary level is heading towards a brighter future with the initiation of new NCEE reform.Keywords: English curriculum, failure, NCEE, new possibilities, pedagogical, policy analysis, reform
Procedia PDF Downloads 1412953 Fabrication of Wollastonite/Hydroxyapatite Coatings on Zirconia by Room Temperature Spray Process
Authors: Jong Kook Lee, Sangcheol Eum, Jaehong Kim
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Wollastonite/hydroxyapatite composite coatings on zirconia were obtained by room temperature spray process. Wollastonite powder was synthesized by solid-state reaction between calcite and silica powder. Hydroxyapatite powder was prepared from bovine bone by the calcination at 1200oC 1h. From two starting raw powders, three kinds of powder mixture were obtained by the ball milling for 24h. By using these powders, wollastonite/hydroxyapatite coatings were fabricated on zirconia substrates by a room temperature spray process, and their microstructure and biological behavior were investigated and compared with pure wollastonite and hydroxyapatite coatings. Wollastonite/hydroxyapatite coatings on zirconia substrates were homogeneously formed in microstructure and had a nanoscaled grain size. The phase composition of the resultant wollastonite/hydroxyapatite coatings was similar to that of the starting powders, however, the grain size of the wollastonite or hydroxyapatite particles was reduced to about 100 nm due to their formation by particle impaction and fracture. The wollastonite/hydroxyapatite coating layer exhibited bioactivity in a stimulated body fluid and forming ability of new hydroxyapatite precipitates of 25 nm during in vitro test in SBF solution, which was enhanced by the increasing wollastonite content.Keywords: wollastonite, hydroxyapatite composite coatings, room temperature spay process, zirconia
Procedia PDF Downloads 4762952 Study of the Biological Activity of a Ganglioside-Containing Drug (Cronassil) in an Experimental Model of Multiple Sclerosis
Authors: Hasmik V. Zanginyan, Gayane S. Ghazaryan, Laura M. Hovsepyan
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Experimental autoimmune encephalomyelitis (EAE) is an inflammatory demyelinating disease of the central nervous system that is induced in laboratory animals by developing an immune response against myelin epitopes. The typical clinical course is ascending palsy, which correlates with inflammation and tissue damage in the thoracolumbar spinal cord, although the optic nerves and brain (especially the subpial white matter and brainstem) are also often affected. With multiple sclerosis, there is a violation of lipid metabolism in myelin. When membrane lipids (glycosphingolipids, phospholipids) are disturbed, metabolites not only play a structural role in membranes but are also sources of secondary mediators that transmit multiple cellular signals. The purpose of this study was to investigate the effect of ganglioside as a therapeutic agent in experimental multiple sclerosis. The biological activity of a ganglioside-containing medicinal preparation (Cronassial) was evaluated in an experimental model of multiple sclerosis in laboratory animals. An experimental model of multiple sclerosis in rats was obtained by immunization with myelin basic protein (MBP), as well as homogenization of the spinal cord or brain. EAE was induced by administering a mixture of an encephalitogenic mixture (EGM) with Complete Freund’s Adjuvant. Mitochondrial fraction was isolated in a medium containing 0,25 M saccharose and 0, 01 M tris buffer, pH - 7,4, by a method of differential centrifugation on a K-24 centrifuge. Glutathione peroxidase activity was assessed by reduction reactions of hydrogen peroxide (H₂O₂) and lipid hydroperoxides (ROOH) in the presence of GSH. LPO activity was assessed by the amount of malondialdehyde (MDA) in the total homogenate and mitochondrial fraction of the spinal cord and brain of control and experimental autoimmune encephalomyelitis rats. MDA was assessed by a reaction with Thiobarbituric acid. For statistical data analysis on PNP, SPSS (Statistical Package for Social Science) package was used. The nature of the distribution of the obtained data was determined by the Kolmogorov-Smirnov criterion. The comparative analysis was performed using a nonparametric Mann-Whitney test. The differences were statistically significant when р ≤ 0,05 or р ≤ 0,01. Correlational analysis was conducted using a nonparametric Spearman test. In the work, refrigeratory centrifuge, spectrophotometer LKB Biochrom ULTROSPECII (Sweden), pH-meter PL-600 mrc (Israel), guanosine, and ATP (Sigma). The study of the process of lipid peroxidation in the total homogenate of the brain and spinal cord in experimental animals revealed an increase in the content of malonic dialdehyde. When applied, Cronassial observed normalization of lipid peroxidation processes. Reactive oxygen species, causing lipid peroxidation processes, can be toxic both for neurons and for oligodendrocytes that form myelin, causing a violation of their lipid composition. The high content of lipids in the brain and the uniqueness of their structure determines the nature of the development of LPO processes. The lipid layer of cellular and intracellular membranes performs two main functions -barrier and matrix (structural). Damage to the barrier leads to dysregulation of intracellular processes and severe disorders of cellular functions.Keywords: experimental autoimmune encephalomyelitis, multiple sclerosis, neuroinflammation, therapy
Procedia PDF Downloads 922951 Identifying Understanding Expectations of School Administrators Regarding School Assessment
Authors: Eftah Bte. Moh Hj Abdullah, Izazol Binti Idris, Abd Aziz Bin Abd Shukor
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This study aims to identify the understanding expectations of school administrators concerning school assessment. The researcher utilized a qualitative descriptive study on 19 administrators from three secondary schools in the North Kinta district. The respondents had been interviewed on their understanding expectations of school assessment using the focus group discussion method. Overall findings showed that the administrators’ understanding expectations of school assessment was weak; especially in terms of content focus, articulation across age and grade, transparency and fairness, as well as the pedagogical implications. Findings from interviews indicated that administrators explained their understanding expectations of school assessment from the aspect of school management, and not from the aspect of instructional leadership or specifically as assessment leaders. The study implications from the administrators’ understanding expectations may hint at the difficulty of the administrators to function as assessment leaders, in order to reduce their focus as manager, and move towards their primary role in the process of teaching and learning. The administrator, as assessment leaders, would be able to reach assessment goals via collaboration in identifying and listing teacher assessment competencies, how to construct assessment capacity, how to interpret assessment correctly, the use of assessment and how to use assessment information to communicate confidently and effectively to the public.Keywords: assessment leaders, assessment goals, instructional leadership, understanding expectation of assessment
Procedia PDF Downloads 4582950 Culturally Responsive Teaching for Learner Diversity in Czech Schools: A Literature Review
Authors: Ntite Orji Kalu, Martina Kurowski
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Until recently, the Czech Republic had an educational system dominated by indigenous people, who accounted for 95% of the school population. With the increasing influx of migrants and foreign students, especially from outside European Union, came a great disparity among the quality of learners and their learning needs and consideration for the challenges associated with being a minority and living within a foreign culture. This has prompted the research into ways of tailoring the educational system to meet the rising demand of learning styles and needs for the diverse learners in the Czech classrooms. Literature is reviewed regarding the various ways to accommodate the international students considering racial differences, focusing on theoretical approach and pedagogical principles. This study examines the compulsory educational system of the Czech Republic and the position and responsibility of the teacher in fostering a culturally sensitive and inclusive learning environment. Descriptive and content analysis is relied upon for this study. Recommendations are made for stakeholders to imbibe a more responsive environment that enhances the cultural and social integration of all learners.Keywords: culturally responsive teaching, cultural competence, diversity, learners, inclusive education, Czech schools
Procedia PDF Downloads 1462949 Availability of Metals in Fired Bricks Incorporating Harbour Sediments
Authors: Fabienne Baraud, Lydia Leleyter, Sandra Poree, Melanie Lemoine, Fatiha Oudghiri
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Alternative solutions to immersion at sea are searched for the huge amounts of dredged sediments around the world that might contain various types of contaminants. Possible re-uses of such materials in civil engineering appear as sustainable solutions. The French SEDIBRIC project (valorisation de SEDIments en BRIQues et tuiles) aims to replace a part of natural clays with dredged sediments in the preparation of fired bricks. The potential environmental impact of this re-use is explored to complete the technical and economic feasibility of the study. As part of the project, we investigate the environmental availability of metallic elements (Al, Ca, Cd, Co, Cr, Cu, Fe, Ni, Mg, Mn, Pb, Ti, and Zn) initially present in the dredged sediments selected for the project. Leaching tests (with H₂O, HCl, or EDTA) are conducted in the sediments than in the final bricks in order to evaluate the possible influence of some steps of the bricks manufacturing (desalination pre-treatment, firing, etc.). The desalination pre-treatment using tap water has no or few impacts on the environmental availability of the studied elements. On the opposite, the firing process (900°C) affects the value of the total content of elements detected in the bricks but also the environmental availability for various elements. For instance, Cd, Cu, Pb, and Zn are stabilized in the bricks, whereas the availability of some other elements (i.e., Cr, Ni) increases, depending on the nature of the extracting solution.Keywords: availability, bricks, dredged sediments, metals
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