Search results for: distributed power generation
1176 Vibro-Acoustic Modulation for Crack Detection in Windmill Blades
Authors: Abdullah Alnutayfat, Alexander Sutin
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One of the most important types of renewable energy resources is wind energy which can be produced by wind turbines. The blades of the wind turbine are exposed to the pressure of the harsh environment, which causes a significant issue for the wind power industry in terms of the maintenance cost and failure of blades. One of the reliable methods for blade inspection is the vibroacoustic structural health monitoring (SHM) method which examines information obtained from the structural vibrations of the blade. However, all vibroacoustic SHM techniques are based on comparing the structural vibration of intact and damaged structures, which places a practical limit on their use. Methods for nonlinear vibroacoustic SHM are more sensitive to damage and cracking and do not need to be compared to data from the intact structure. This paper presents the Vibro-Acoustic Modulation (VAM) method based on the modulation of high-frequency (probe wave) by low-frequency loads (pump wave) produced by the blade rotation. The blade rotation alternates bending stress due to gravity, leading to crack size variations and variations in the blade resonance frequency. This method can be used with the classical SHM vibration method in which the blade is excited by piezoceramic actuator patches bonded to the blade and receives the vibration response from another piezoceramic sensor. The VAM modification of this method analyzes the spectra of the detected signal and their sideband components. We suggest the VAM model as the simple mechanical oscillator, where the parameters of the oscillator (resonance frequency and damping) are varied due to low-frequency blade rotation. This model uses the blade vibration parameters and crack influence on the blade resonance properties from previous research papers to predict the modulation index (MI).Keywords: wind turbine blades, damaged detection, vibro-acoustic structural health monitoring, vibro-acoustic modulation
Procedia PDF Downloads 851175 Financial Liberalization, Exchange Rates and Demand for Money in Developing Economies: The Case of Nigeria, Ghana and Gambia
Authors: John Adebayo Oloyhede
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This paper examines effect of financial liberalization on the stability of the demand for money function and its implication for exchange rate behaviour of three African countries. As the demand for money function is regarded as one of the two main building blocks of most exchange rate determination models, the other being purchasing power parity, its stability is required for the monetary models of exchange rate determination to hold. To what extent has the liberalisation policy of these countries, for instance liberalised interest rate, affected the demand for money function and what has been the consequence on the validity and relevance of floating exchange rate models? The study adopts the Autoregressive Instrumental Package (AIV) of multiple regression technique and followed the Almon Polynomial procedure with zero-end constraint. Data for the period 1986 to 2011 were drawn from three developing countries of Africa, namely: Gambia, Ghana and Nigeria, which did not only start the liberalization and floating system almost at the same period but share similar and diverse economic and financial structures. Its findings show that the demand for money was a stable function of income and interest rate at home and abroad. Other factors such as exchange rate and foreign interest rate exerted some significant effect on domestic money demand. The short-run and long-run elasticity with respect to income, interest rates, expected inflation rate and exchange rate expectation are not greater than zero. This evidence conforms to some extent to the expected behaviour of the domestic money function and underscores its ability to serve as good building block or assumption of the monetary model of exchange rate determination. This will, therefore, assist appropriate monetary authorities in the design and implementation of further financial liberalization policy packages in developing countries.Keywords: financial liberalisation, exchange rates, demand for money, developing economies
Procedia PDF Downloads 3731174 Red Herring Innovation: Twelve Paradoxes of Innovation Ecosystem in a Closed Society
Authors: Mohammad Hossein Badamchi
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In Iran as well as other developing countries instituting innovation and entrepreneurship ecosystems by government around the universities is the new imported fashion of modernization and development in the 21st century. In recent decade various statesmen, policy makers, university administrations, economists and development theorists are emphasizing excitingly about the new “start-ups” which are going to solve all economic problems and backwardness of the country. However, critical study of modernization practices in Iran implies that this new trend is suffering from conventional deficiency of modernization planning in 20th century. This article is going to depict the misunderstandings of a situation which we can name “Pseudo-innovation in a closed society” by presenting these 12 paradoxes of this new system, actually happening in Iran: (1) Innovation without freedom? Fiction of innovation in a patriarchal state (2) Entrepreneurship without free market? Fiction of entrepreneurship in a rentier-state. (3) Ecosystem or a state-glasshouse? Is it possible to make and plan an innovation? (4) Innovation; epistemic or practical? How academic innovation could happen abstractly out of context? (5) Risk and Lucre: innovation to protect power and property?! (6) Silicon-valley mirage: what is in common between American-Iranian polity? (7) Information or Communication? ICT startups to restrict the internet (8) The elite paradox: new proletariat of private sector, new governmental clerk or a new path of brain drain? (9) Innovation or commercialization? Revisiting Schumpeterian creative destruction (10) The friendship of Jungle and fire: paradox of public science and market (11) Innovation and revolution: top-down or bottom-up paradox in an Iranian experience (12) Technology instead of civil society: ultimate result of innovation in a closed society. Through explaining these paradoxes we can gradually penetrate the real rationality of Pseudo-innovation ecosystem in a closed society, which can be understood as new-Neopatriarchy reconstruction of traditional patriarchal politics, economy and culture in Iran.Keywords: innovation, critical sociology, modernisation, Iran, closed society
Procedia PDF Downloads 751173 A One-Dimensional Modeling Analysis of the Influence of Swirl and Tumble Coefficient in a Single-Cylinder Research Engine
Authors: Mateus Silva Mendonça, Wender Pereira de Oliveira, Gabriel Heleno de Paula Araújo, Hiago Tenório Teixeira Santana Rocha, Augusto César Teixeira Malaquias, José Guilherme Coelho Baeta
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The stricter legislation and the greater demand of the population regard to gas emissions and their effects on the environment as well as on human health make the automotive industry reinforce research focused on reducing levels of contamination. This reduction can be achieved through the implementation of improvements in internal combustion engines in such a way that they promote the reduction of both specific fuel consumption and air pollutant emissions. These improvements can be obtained through numerical simulation, which is a technique that works together with experimental tests. The aim of this paper is to build, with support of the GT-Suite software, a one-dimensional model of a single-cylinder research engine to analyze the impact of the variation of swirl and tumble coefficients on the performance and on the air pollutant emissions of an engine. Initially, the discharge coefficient is calculated through the software Converge CFD 3D, given that it is an input parameter in GT-Power. Mesh sensitivity tests are made in 3D geometry built for this purpose, using the mass flow rate in the valve as a reference. In the one-dimensional simulation is adopted the non-predictive combustion model called Three Pressure Analysis (TPA) is, and then data such as mass trapped in cylinder, heat release rate, and accumulated released energy are calculated, aiming that the validation can be performed by comparing these data with those obtained experimentally. Finally, the swirl and tumble coefficients are introduced in their corresponding objects so that their influences can be observed when compared to the results obtained previously.Keywords: 1D simulation, single-cylinder research engine, swirl coefficient, three pressure analysis, tumble coefficient
Procedia PDF Downloads 1061172 Microwave Assisted Rapid Synthesis of Nano-Binder from Renewable Resource and Their Application in Textile Printing
Authors: K. Haggag, N. S. Elshemy
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Due to limited fossil resource and an increased need for environmentally friendly, sustainable technologies, the importance of using renewable feed stocks in textile industry area will increase in the decades to come. This research highlights some of the perspectives in this area. Alkyd resins for high characterization and reactive properties, completely based on commercially available renewable resources (sunflower and/or soybean oil) were prepared and characterized. In this work, we present results on the synthesis of various alkyd resins according to the alcoholysis – polyesterification process under different preparation conditions using a microwave synthesis as energy source to determine suitable reaction conditions. Effects of polymerization parameters, such as catalyst ratio, reaction temperature and microwave power level have been studied. The prepared binder was characterized via FT-IR, scanning electron microscope (SEM) and transmission electron microscope (TEM), in addition to acid value (AV), iodine value (IV), water absorbance, weight loss, and glass transition temperature. The prepared binder showed high performance physico-mechanical properties. TEM analysis showed that the polymer latex nanoparticle within range of 20–200 nm. The study involved the application of the prepared alkyd resins as binder for pigment printing process onto cotton fabric by using a flat screen technique and the prints were dried and thermal cured. The optimum curing conditions were determined, color strength and fastness properties of pigment printed areas to light, washing, perspiration and crocking were evaluated. The rheological properties and apparent viscosity of prepared binders were measured in addition roughness of the prints was also determined.Keywords: nano-binder, microwave heating, renewable resource, alkyd resins, sunflower oil, soybean oil
Procedia PDF Downloads 3731171 The Effect of Artificial Intelligence on Electric Machines and Welding
Authors: Mina Malak Zakaria Henin
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The finite detail evaluation of magnetic fields in electromagnetic devices shows that the machine cores revel in extraordinary flux patterns consisting of alternating and rotating fields. The rotating fields are generated in different configurations variety, among circular and elliptical, with distinctive ratios between the fundamental and minor axes of the flux locus. Experimental measurements on electrical metal uncovered one-of-a-kind flux patterns that divulge distinctive magnetic losses in the samples below the test. Therefore, electric machines require unique interest throughout the core loss calculation technique to bear in mind the flux styles. In this look, a circular rotational unmarried sheet tester is employed to measure the middle losses in the electric-powered metallic pattern of M36G29. The sample becomes exposed to alternating fields, circular areas, and elliptical fields with axis ratios of zero.2, zero. Four, 0.6 and 0.8. The measured statistics changed into applied on 6-4 switched reluctance motors at 3 distinctive frequencies of interest to the industry 60 Hz, 400 Hz, and 1 kHz. The effects reveal an excessive margin of error, which can arise at some point in the loss calculations if the flux pattern difficulty is overlooked. The mistake in exceptional components of the gadget associated with considering the flux styles may be around 50%, 10%, and a couple of at 60Hz, 400Hz, and 1 kHz, respectively. The future paintings will focus on the optimization of gadget geometrical shape, which has a primary effect on the flux sample on the way to decrease the magnetic losses in system cores.Keywords: converters, electric machines, MEA (more electric aircraft), PES (power electronics systems) synchronous machine, vector control Multi-machine/ Multi-inverter, matrix inverter, Railway tractionalternating core losses, finite element analysis, rotational core losses
Procedia PDF Downloads 281170 The Prevailing Practice of Night Hunting in Central Bhutan: Traditional Practice of Courtship as a Sexual Coercion to Women
Authors: Ugyen Phuntsho
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A popular and entrenched custom as a form of courtship has been practicing in Bhutan from long time back. This custom is widely being practiced in the villages of eastern and central Bhutan. This long-practiced custom is known by different terms in Bhutan, but it is popularly known to the foreigners as ‘night hunting’. This unique form of courtship custom involves the boy visiting the girl’s house stealthily under the cover of darkness without any pre-appointment. It is still perceived as a serving norms of courtship in the villages in central Bhutan. For many years this practice of night hunting has been in the spotlight of debate as a harmless culture but as sexual violence against women. However, this study examined the changing perception on the night hunting as a form of courtship custom or sexual coercion to women by employing the in-depth interview with 42 participants (21 females and 9 males from 3 different villages, 5 females and 7 males from urban areas) in central Bhutan. Moreover, the study investigated the gender inequality linked with the practice of night hunting in the rural areas of central Bhutan. The study revealed the changing perception on night hunting as more of sexual coercion taking place during night hunting than merely tolerating it as traditional form of practice of courtship. The finding of this study revealed unlike the past; this practice serves minimal social purpose in the society as the social changes with the development of socioeconomic of the people. However, the practice of night hunting is still prevalent at the villages, and it is known that the social power, single and widow women, valuing of village endogamy practices and the popular notion of pride of promiscuous amongst the men have attributed in sexual coercion and in ultimate victimization of the women. Furthermore, the study revealed the gender inequality linked with night hunting thus significantly increasing the vulnerability of rural women to other forms of violence in the society.Keywords: courtship, custom, men, night hunting, practice, sexual coercion, women, violence
Procedia PDF Downloads 2471169 Mechanical Properties of Lithium-Ion Battery at Different Packing Angles Under Impact Loading
Authors: Wei Zhao, Yuxuan Yao, Hao Chen
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In order to find out the mechanical properties and failure behavior of lithium-ion batteries, drop hammer impact experiments and finite element simulations are carried out on batteries with different packed angles. Firstly, a drop hammer impact experiment system, which is based on the DHR-1808 drop hammer and oscilloscope, is established, and then a drop test of individual batteries and packed angles of 180 ° and 120 ° are carried out. The image of battery deformation, force-time curve and voltage-time curve are recorded. Secondly, finite element models of individual batteries and two packed angles are established, and the results of the test and simulation are compared. Finally, the mechanical characteristics and failure behavior of lithium-ion battery modules with the packed arrangement of 6 * 6 and packing angles of 180 °, 120 °, 90 ° and 60 ° are analyzed under the same velocity with different battery packing angles, and the same impact energy with different impact velocity and different packing angles. The result shows that the individual battery is destroyed completely in the drop hammer impact test with an initial impact velocity of 3m/s and drop height of 459mm, and the voltage drops to close to 0V when the test ends. The voltage drops to 12V when packed angle of 180°, and 3.6V when packed angle of 120°. It is found that the trend of the force-time curve between simulation and experiment is generally consistent. The difference in maximum peak value is 3.9kN for a packing angle of 180° and 1.3kN for a packing angle of 120°. Under the same impact velocity and impact energy, the strain rate of the battery module with a packing angle of 180° is the lowest, and the maximum stress can reach 26.7MPa with no battery short-circuited. The research under our experiment and simulation shows that the lithium-ion battery module with a packing angle of 180 ° is the least likely to be damaged, which can sustain the maximum stress under the same impact load.Keywords: battery module, finite element simulation, power battery, packing angle
Procedia PDF Downloads 701168 Gender Discrimination and Wellbeing in Family Sphere Due to Male Migration and Remittances: A Study of Doaba Region of Punjab
Authors: Atinder Pal Kaur
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A central characteristic of people is their apparent movement from one station to other for their sustenance. Human migration has become one of the most challenging issues faced by the world today. Migration represents an important dimension in world-wide setting; and remittances received by families constitute a major agent in integrating societies in the all over the world, both economically and socially. This paper is an attempt to explore the impact of male migration and remittances upon the family system. This paper brings out how the women play the role of head of the household and take all the economic decisions, but still faces discrimination in the family, that bring loneliness and emotional breakdown on their personal front. For the purpose of this study, data was collected using 30 interviews and 10 case studies in the Doaba region of Punjab. The respondents were classified into two age groups 20-35 years and above 40 years aged women whose husbands migrated abroad. The findings of this study revealed that even though the women were taking some of the economic decisions, but in majority of the cases the patriarchal structure still existed and power remained in the hands of their husbands or in-laws. It was found that women of different age groups reported differently in terms of authority that they have regarding remittances and its consequences in their emotional well-being. The distinction related to their participation in public and private spheres still exists and public spheres are mostly dominated by male members of the family. It can be concluded that freedom of women to take decision on their own is still restricted and they are subjugated to follow their husband or in-law’s opinion in matters related to both public and private spheres. However, old age group women enjoyed more independence and freedom to take decision in comparison to young age women. Loneliness and depression were more common in the young age respondent’s group than in old age women.Keywords: gender discrimination, migration, patriarchal structure, remittances
Procedia PDF Downloads 2641167 Numerical Investigation of 3D Printed Pin Fin Heat Sinks for Automotive Inverter Cooling Application
Authors: Alexander Kospach, Fabian Benezeder, Jürgen Abraham
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E-mobility poses new challenges for inverters (e.g., higher switching frequencies) in terms of thermal behavior and thermal management. Due to even higher switching frequencies, thermal losses become greater, and the cooling of critical components (like insulated gate bipolar transistor and diodes) comes into focus. New manufacturing methods, such as 3D printing, enable completely new pin-fin structures that can handle higher waste heat to meet the new thermal requirements. Based on the geometrical specifications of the industrial partner regarding the manufacturing possibilities for 3D printing, different and completely new pin-fin structures were numerically investigated for their hydraulic and thermal behavior in fundamental studies assuming an indirect liquid cooling. For the 3D computational fluid dynamics (CFD) thermal simulations OpenFOAM was used, which has as numerical method the finite volume method for solving the conjugate heat transfer problem. A steady-state solver for turbulent fluid flow and solid heat conduction with conjugate heat transfer between solid and fluid regions was used for the simulations. In total, up to fifty pinfin structures and arrangements, some of them completely new, were numerically investigated. On the basis of the results of the principal investigations, the best two pin-fin structures and arrangements for the complete module cooling of an automotive inverter were numerically investigated and compared. There are clear differences in the maximum temperatures for the critical components, such as IGTBs and diodes. In summary, it was shown that 3D pin fin structures can significantly contribute to the improvement of heat transfer and cooling of an automotive inverter. This enables in the future smaller cooling designs and a better lifetime of automotive inverter modules. The new pin fin structures and arrangements can also be applied to other cooling applications where 3D printing can be used.Keywords: pin fin heat sink optimization, 3D printed pin fins, CFD simulation, power electronic cooling, thermal management
Procedia PDF Downloads 1031166 Partially Aminated Polyacrylamide Hydrogel: A Novel Approach for Temporary Oil and Gas Well Abandonment
Authors: Hamed Movahedi, Nicolas Bovet, Henning Friis Poulsen
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Following the advent of the Industrial Revolution, there has been a significant increase in the extraction and utilization of hydrocarbon and fossil fuel resources. However, a new era has emerged, characterized by a shift towards sustainable practices, namely the reduction of carbon emissions and the promotion of renewable energy generation. Given the substantial number of mature oil and gas wells that have been developed inside the petroleum reservoir domain, it is imperative to establish an environmental strategy and adopt appropriate measures to effectively seal and decommission these wells. In general, the cement plug serves as a material for plugging purposes. Nevertheless, there exist some scenarios in which the durability of such a plug is compromised, leading to the potential escape of hydrocarbons via fissures and fractures within cement plugs. Furthermore, cement is often not considered a practical solution for temporary plugging, particularly in the case of well sites that have the potential for future gas storage or CO2 injection. The Danish oil and gas industry has promising potential as a prospective candidate for future carbon dioxide (CO2) injection, hence contributing to the implementation of carbon capture strategies within Europe. The primary reservoir component consists of chalk, a rock characterized by limited permeability. This work focuses on the development and characterization of a novel hydrogel variant. The hydrogel is designed to be injected via a low-permeability reservoir and afterward undergoes a transformation into a high-viscosity gel. The primary objective of this research is to explore the potential of this hydrogel as a new solution for effectively plugging well flow. Initially, the synthesis of polyacrylamide was carried out using radical polymerization inside the confines of the reaction flask. Subsequently, with the application of the Hoffman rearrangement, the polymer chain undergoes partial amination, facilitating its subsequent reaction with the crosslinker and enabling the formation of a hydrogel in the subsequent stage. The organic crosslinker, glutaraldehyde, was employed in the experiment to facilitate the formation of a gel. This gel formation occurred when the polymeric solution was subjected to heat within a specified range of reservoir temperatures. Additionally, a rheological survey and gel time measurements were conducted on several polymeric solutions to determine the optimal concentration. The findings indicate that the gel duration is contingent upon the starting concentration and exhibits a range of 4 to 20 hours, hence allowing for manipulation to accommodate diverse injection strategies. Moreover, the findings indicate that the gel may be generated in environments characterized by acidity and high salinity. This property ensures the suitability of this substance for application in challenging reservoir conditions. The rheological investigation indicates that the polymeric solution exhibits the characteristics of a Herschel-Bulkley fluid with somewhat elevated yield stress prior to solidification.Keywords: polyacrylamide, hofmann rearrangement, rheology, gel time
Procedia PDF Downloads 771165 Retrofitting of Asymmetric Steel Structure Equipped with Tuned Liquid Column Dampers by Nonlinear Finite Element Modeling
Authors: A. Akbarpour, M. R. Adib Ramezani, M. Zhian, N. Ghorbani Amirabad
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One way to improve the performance of structures against of earthquake is passive control which requires no external power source. In this research, tuned liquid column dampers which are among of systems with the capability to transfer energy between various modes of vibration, are used. For the first time, a liquid column damper for vibration control structure is presented. After modeling this structure in design building software and performing the static and dynamic analysis and obtaining the necessary parameters for the design of tuned liquid column damper, the whole structure will be analyzed in finite elements software. The tuned liquid column dampers are installed on the structure and nonlinear time-history analysis is done in two cases of structures; with and without dampers. Finally the seismic behavior of building in the two cases will be examined. In this study the nonlinear time-history analysis on a twelve-story steel structure equipped with damper subject to records of earthquake including Loma Prieta, Northridge, Imperiall Valley, Pertrolia and Landers was performed. The results of comparing between two cases show that these dampers have reduced lateral displacement and acceleration of levels on average of 10%. Roof displacement and acceleration also reduced respectively 5% and 12%. Due to structural asymmetric in the plan, the maximum displacements of surrounding structures as well as twisting were studied. The results show that the dampers lead to a 10% reduction in the maximum response of structure stories surrounding points. At the same time, placing the dampers, caused to reduce twisting on the floor plan of the structure, Base shear of structure in the different earthquakes also has been reduced on the average of 6%.Keywords: retrofitting, passive control, tuned liquid column damper, finite element analysis
Procedia PDF Downloads 4141164 Vibration Analysis of FGM Sandwich Panel with Cut-Outs Using Refined Higher-Order Shear Deformation Theory (HSDT) Based on Isogeometric Analysis
Authors: Lokanath Barik, Abinash Kumar Swain
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This paper presents vibration analysis of FGM sandwich structure with a complex profile governed by refined higher-order shear deformation theory (RHSDT) using isogeometric analysis (IGA). Functionally graded sandwich plates provide a wide range of applications in aerospace, defence, and aircraft industries due to their ability to distribute material functions to influence the thermo-mechanical properties as desired. In practical applications, these structures generally have intrinsic profiles, and their response to loads is significantly affected due to cut-outs. IGA is primarily a NURBS-based technique that is effective in solving higher-order differential equations due to its inherent C1 continuity imposition in solution space for a single patch. Complex structures generally require multiple patches to accurately represent the geometry, and hence, there is a loss of continuity at adjoining patch junctions. Therefore, patch coupling is desired to maintain continuity requirements throughout the domain. In this work, a novel strong coupling approach is provided that generates a well-defined NURBS-based model while achieving continuity. The methodology is validated by free vibration analysis of sandwich plates with present literature. The results are in good agreement with the analytical solution for different plate configurations and power law indexes. Numerical examples of rectangular and annular plates are discussed with variable boundary conditions. Additionally, parametric studies are provided by varying the aspect ratio, porosity ratio and their influence on the natural frequency of the plate.Keywords: vibration analysis, FGM sandwich structure, multipatch geometry, patch coupling, IGA
Procedia PDF Downloads 821163 Designing Entrepreneurship Education Contents for Entrepreneurial Intention Building among Undergraduates in India
Authors: Sumita Srivastava
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Despite several measures taken by the Government of India, entrepreneurship is still not perceived as a viable career option by the young generation. Although the rate of startups has improved a little after the penetration of e portals as business platforms, still the numbers are not very significant. It is also important to note that entrepreneurial initiatives are mostly taken up by graduates of premier institutions of India like Indian Institute of Technology (IITs) and Indian Institute of Management (IIMs). The scenario is not very satisfactory amongst the masses graduating from mainstream universities of the country. Indian youth at large are not attracted towards entrepreneurship as a career choice. The reason probably lies in the social fabric of the country and inappropriate education system which does not support the entrepreneurship at large amongst youth in the country. Education is critical to the development of an economy from the poverty level to the level of self-sustenance and development. The current curriculum in the majority of business schools in India prepares the average graduate to become employed by the available firms or business owners in society. For graduates in other streams, employment opportunities are very limited. The aim of this study was to identify and design entrepreneurship education contents to encourage undergraduates to pursue entrepreneurship as a career choice. This comprehensive study was conducted in multiple stages. Extensive research was conducted at each stage with an appropriate methodology. These stages of the project study were interconnected with each other, and each preceding stage provided inputs for the following stage of the study. In the first stage of the study, an empirical analysis was conducted to understand the current state of entrepreneurial intentions of undergraduates of Agra city. Various stakeholders were contacted at the stage, including students (n = 500), entrepreneurs (n = 20) and academicians and field experts (n = 10). At the second stage of the project study, a systems science technique, Nominal Group Technique (NGT) was used to identify the critical elements of entrepreneurship education in India based upon the findings of stage 1. The application of the Nominal Group Technique involved a workshop format; 15 domain experts participated in the workshop. Throughout the process, a democratic process was followed to avoid individual dominance and premature focusing on a single idea. The study obtained 63 responses from experts for effective entrepreneurship education in India. The responses were reduced to seven elements after a few thematic iterations. These elements were then segregated into content (knowledge, skills and attitude) and learning interaction on the basis of experts’ responses. After identifying critical elements of entrepreneurship education in the previous stage, the course was designed and validated at stage 3 of the project. Scientific methods were used at this stage to validate the curriculum contents and training interventions experimentally. The educational and training interventions designed through this study would not only help in developing entrepreneurial intentions but also creating skills relevant to the local entrepreneurial opportunities in the vicinity.Keywords: curriculum design, entrepreneurial intention, entrepreneuship education, nominal group technique
Procedia PDF Downloads 1301162 Semi-Automatic Segmentation of Mitochondria on Transmission Electron Microscopy Images Using Live-Wire and Surface Dragging Methods
Authors: Mahdieh Farzin Asanjan, Erkan Unal Mumcuoglu
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Mitochondria are cytoplasmic organelles of the cell, which have a significant role in the variety of cellular metabolic functions. Mitochondria act as the power plants of the cell and are surrounded by two membranes. Significant morphological alterations are often due to changes in mitochondrial functions. A powerful technique in order to study the three-dimensional (3D) structure of mitochondria and its alterations in disease states is Electron microscope tomography. Detection of mitochondria in electron microscopy images due to the presence of various subcellular structures and imaging artifacts is a challenging problem. Another challenge is that each image typically contains more than one mitochondrion. Hand segmentation of mitochondria is tedious and time-consuming and also special knowledge about the mitochondria is needed. Fully automatic segmentation methods lead to over-segmentation and mitochondria are not segmented properly. Therefore, semi-automatic segmentation methods with minimum manual effort are required to edit the results of fully automatic segmentation methods. Here two editing tools were implemented by applying spline surface dragging and interactive live-wire segmentation tools. These editing tools were applied separately to the results of fully automatic segmentation. 3D extension of these tools was also studied and tested. Dice coefficients of 2D and 3D for surface dragging using splines were 0.93 and 0.92. This metric for 2D and 3D for live-wire method were 0.94 and 0.91 respectively. The root mean square symmetric surface distance values of 2D and 3D for surface dragging was measured as 0.69, 0.93. The same metrics for live-wire tool were 0.60 and 2.11. Comparing the results of these editing tools with the results of automatic segmentation method, it shows that these editing tools, led to better results and these results were more similar to ground truth image but the required time was higher than hand-segmentation timeKeywords: medical image segmentation, semi-automatic methods, transmission electron microscopy, surface dragging using splines, live-wire
Procedia PDF Downloads 1691161 Two-Dimensional Van-Der Waals Heterostructure for Highly Energy-Efficient Field-Free Deterministic Spin-Orbit Torque Switching at Room Temperature
Authors: Pradeep Raj Sharma, Bogeun Jang, Jongill Hong
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Spin-orbit torque (SOT) is an efficient approach for manipulating the magnetization of ferromagnetic materials (FMs), providing improved device performance, better compatibility, and ultra-fast switching with lower power consumption compared to spin-transfer torque (STT). Among the various materials and structural designs, two-dimensional (2D) van-der Waals (vdW) layered materials and their heterostructures have been demonstrated as highly scalable and promising device architecture for SOT. In particular, a bilayer heterostructure consisting of fully 2D-vdW-FM, non-magnetic material (NM) offers a potential platform for controlling the magnetization using SOT because of the advantages of being easy to scale and less energy to switch. Here, we report filed-free deterministic switching driven by SOT at room temperature, integrating perpendicularly magnetized 2D-vdW material Fe₃GaTe₂ (FGaT) and NM WTe₂. Pulse current-induced magnetization switching with an ultra-low current density of about 6.5×10⁵ A/cm², yielding a SOT efficiency close to double-digits at 300 K, is reported. These values are two orders of magnitude higher than those observed in conventional heavy metal (HM) based SOT and exceed those reported with 2D-vdW layered materials. WTe₂, a topological semimetal possessing strong SOC and high spin Hall angle, can induce significant spin accumulation with negligible spin loss across the transparent 2D bilayer heterointerface. This promising device architecture enables highly compatible, energy-efficient, non-volatile memory and lays the foundation for designing efficient, flexible, and miniaturized spintronic devices.Keywords: spintronics, spin-orbit torque, spin Hall effect, spin Hall angle, topological semimetal, perpendicular magnetic anisotropy
Procedia PDF Downloads 61160 Rejuvenation of Aged Kraft-Cellulose Insulating Paper Used in Transformers
Authors: Y. Jeon, A. Bissessur, J. Lin, P. Ndungu
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Most transformers employ the usage of cellulose paper, which has been chemically modified through the Kraft process that acts as an effective insulator. Cellulose ageing and oil degradation are directly linked to fouling of the transformer and accumulation of large quantities of waste insulating paper. In addition to technical difficulties, this proves costly for power utilities to deal with. Currently there are no cost effective method for the rejuvenation of cellulose paper that has been documented nor proposed, since renewal of used insulating paper is implemented as the best option. This study proposes and contrasts different rejuvenation methods of accelerated aged cellulose insulating paper by chemical and bio-bleaching processes. Of the three bleaching methods investigated, two are, conventional chlorine-based sodium hypochlorite (m/v), and chlorine-free hydrogen peroxide (v/v), whilst the third is a bio-bleaching technique that uses a bacterium isolate, Acinetobacter strain V2. Through chemical bleaching, varying the strengths of the bleaching reagents at 0.3 %, 0.6 %, 0.9 %, 1.2 %, 1.5 % and 1.8 % over 4 hrs. were analyzed. Bio-bleaching implemented a bacterium isolate, Acinetobacter strain V2, to bleach the aged Kraft paper over 4 hrs. The determination of the amount of alpha cellulose, degree of polymerization and viscosity carried out on Kraft-cellulose insulating paper before and after bleaching. Overall the investigated techniques of chemical and bio-bleaching were successful and effective in treating degraded and accelerated aged Kraft-cellulose insulating paper, however, to varying extents. Optimum conditions for chemical bleaching were attained at bleaching strengths of 1.2 % (m/v) NaOCl and 1.5 % (v/v) H2O2 yielding alpha cellulose contents of 82.4 % and 80.7 % and degree of polymerizations of 613 and 616 respectively. Bio-bleaching using Acinetobacter strain V2 proved to be the superior technique with alpha cellulose levels of 89.0 % and a degree of polymerization of 620. Chemical bleaching techniques require careful and controlled clean-up treatments as it is chlorine and hydrogen peroxide based while bio-bleaching is an extremely eco-friendly technique.Keywords: alpha cellulose, bio-bleaching, degree of polymerization, Kraft-cellulose insulating paper, transformer, viscosity
Procedia PDF Downloads 2701159 Experimental Investigation of Visual Comfort Requirement in Garment Factories and Identify the Cost Saving Opportunities
Authors: M. A. Wijewardane, S. A. N. C. Sudasinghe, H. K. G. Punchihewa, W. K. D. L. Wickramasinghe, S. A. Philip, M. R. S. U. Kumara
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Visual comfort is one of the major parameters that can be taken to measure the human comfort in any environment. If the provided illuminance level in a working environment does not meet the workers visual comfort, it will lead to eye-strain, fatigue, headache, stress, accidents and finally, poor productivity. However, improvements in lighting do not necessarily mean that the workplace requires more light. Unnecessarily higher illuminance levels will also cause poor visual comfort and health risks. In addition, more power consumption on lighting will also result in higher energy costs. So, during this study, visual comfort and the illuminance requirement for the workers in textile/apparel industry were studied to perform different tasks (i.e. cutting, sewing and knitting) at their workplace. Experimental studies were designed to identify the optimum illuminance requirement depending upon the varied fabric colour and type and finally, energy saving potentials due to controlled illuminance level depending on the workforce requirement were analysed. Visual performance of workers during the sewing operation was studied using the ‘landolt ring experiment’. It was revealed that around 36.3% of the workers would like to work if the illuminance level varies from 601 lux to 850 lux illuminance level and 45.9% of the workers are not happy to work if the illuminance level reduces less than 600 lux and greater than 850 lux. Moreover, more than 65% of the workers who do not satisfy with the existing illuminance levels of the production floors suggested that they have headache, eye diseases, or both diseases due to poor visual comfort. In addition, findings of the energy analysis revealed that the energy-saving potential of 5%, 10%, 24%, 8% and 16% can be anticipated for fabric colours, red, blue, yellow, black and white respectively, when the 800 lux is the prevailing illuminance level for sewing operation.Keywords: Landolt Ring experiment, lighting energy consumption, illuminance, textile and apparel industry, visual comfort
Procedia PDF Downloads 2051158 People Vote with Their Feet: The 'Parallel Polis' in South Africa as a Reaction to the Neo-Patrimonial State
Authors: A. Kok
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The South African experience of the general upsurge in protest movements internationally is characterised by a tension between a neo-patrimonial state on the one hand, and a society with growing middle-class needs and interests on the other. This tension translates into local community service delivery protests – often violent in nature – that have been steadily increasing in number since 2008, student uprisings that have reached their height in October 2015, and various continuing local social #MustFall movements that are geared towards addressing government corruption and transforming neo-liberal structures. As a result, growing citizen (and non-citizen) revolt in South Africa has seen the (i) creeping securitization of the neo-patrimonial state and (ii) the 'top-down' misuse of a current 'bottom-up' people’s ideology, decoloniality, in an attempt by a faction in the ruling party (representing the neo-patrimonial state) to legitimize its actions and consolidate its power. The neo-patrimonial state’s creeping securitization and ideological positioning lead to a further mistrust of public institutions, people’s disengagement with traditional politics, and the creation of a 'parallel polis' by citizens and non-citizens that bypasses the official and oftentimes corrupt structures of the state. By applying the concept 'parallel polis' – originally developed by Václav Benda in connection with the movement Charter 77 in former Czechoslovakia – to a South African case study, it is illustrated that, even in the absence of overt oppression and the use of terror by a ruling elite, entrenched neo-patrimonialism can be potent enough to fuel the creation of various independent parallel public spheres (or, as a whole, understood as a 'parallel polis') to bypass dysfunctional state channels. A flourishing parallel polis offers possibilities for political, social and economic renewal. This is especially relevant in the consolidation of South Africa’s relatively young democracy.Keywords: decoloniality, neo-patrimonialism, 'parallel polis', protest movements, South Africa, state securitization
Procedia PDF Downloads 2211157 Evaluating the Impact of English Immersion in Kolkata’s High-Cost Private Schools
Authors: Ashmita Bhattacharya
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This study aims to investigate whether the English immersion experience offered by Kolkata’s high-cost private English-medium schools lead to additive or subtractive language learning outcomes for students. In India, English has increasingly become associated with power, social status, and socio-economic mobility. As a result, a proliferation of English-medium schools has emerged across Kolkata and the wider Indian context. While in some contexts, English language learning can be an additive experience, in others, it can be subtractive where proficiency in English is developed at the expense of students’ native language proficiency development. Subtractive educational experiences can potentially have severe implications, including heritage language loss, detachment from cultural roots, and a diminished sense of national identity. Thus, with the use of semi-structured interviews, the language practices and lived experiences of 12 former students who attended high-cost private English-medium schools in Kolkata were thoroughly explored. The data collected was thematically coded and analysis was conducted using the Thematic Analysis approach. The findings indicate that the English immersion experience at Kolkata’s high-cost private English-medium schools provide a subtractive language learning experience to students. Additionally, this study suggests that robust home-based support for native languages might be crucial for mitigating the effects of subtractive English education. Furthermore, the study underscores the importance of integrating opportunities within schools that promote Indian languages and cultures as it can create a more positive, inclusive, and culturally responsive environment. Finally, although subject to further evaluation, the study recommends the implementation of bilingual and multilingual educational systems and provides suggestions for future research in this area.Keywords: bilingual education, English immersion, language loss, multilingual education, subtractive language learning
Procedia PDF Downloads 301156 Prospective Cohort Study on Sequential Use of Catheter with Misoprostol vs Misoprostol Alone for Second Trimester Medical Abortion
Authors: Hanna Teklu Gebregziabher
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Background: A variety of techniques for medical termination of second-trimester pregnancy can be used, but there is no consensus about which is the best. Even though most evidence suggests the combined use of intracervical Foley catheter and vaginal misoprostol is safe, effective, and acceptable method for termination of second-trimester pregnancy, which is comparable to mifepristone-misoprostol combination regimen with lower cost and no additional maternal risks. The use of mifepristone and misoprostol alone with no other procedure is still the most common procedure in different institutions for 2nd-trimester pregnancy. Methods: A cross-sectional comparative prospective study design is employed on women who were admitted for 2nd-trimester medical abortion and medical abortion failed or if there was no change in cervical status after 24 hours of 1st dose of misoprostol. The study was conducted at St. Paulose Hospital Millennium Medical College. A sample of 44 participants in each arm was necessary to give a two-tailed test, a type 1 error of 5%, 80% statistical power, and a 1:1 ratio among groups. Thus, a total of 94 cases, 47 from each arm, were recruited. Data was entered and cleaned by using Epi-info and analyzed using SPSS version 29.0 statistical software and was presented in descriptive and tabular forms. Different variables were cross-tabulated and compared for significant differences and statistical analysis using the chi-square test and independent t-test, to conclude. Result: There was a significant difference between the two groups on induction to expulsion time and number of doses used. The mean ± SD of induction to expulsion time for those used misoprostol alone was 48.09 ± 11.86 and those who used trans-cervical catheter sequentially with misoprostol were 36.7 ±6.772. Conclusion: The use of a trans-cervical Foley catheter in conjunction with misoprostol in a sequential manner is a more effective, safe, and easily accessible procedure. In addition, the cost of utilizing the catheter is less compared to the cost of misoprostol and is readily available. As a good substitute, we advised using Trans-cervical Catether even for medical abortions performed in the second trimester.Keywords: second trimester, medical abortion, catheter, misoprostol
Procedia PDF Downloads 461155 The Political Pedagogy of Everyday Life in the French Revolution
Authors: Michael Ruiz
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Many scholars view the French Revolution as the origins of ‘modern nationalism,’ citing the unprecedented rhetorical power of ‘the nation’ and the emergence of a centralized, modern nation-state during this time. They have also stressed the role of public education in promoting a national language and creating a sense of shared national identity among the masses. Yet as many cultural historians have shown, revolutionary leaders undertook an unprecedented campaign to overhaul French culture in the 1790s in order to cultivate these national ideals and inspire Republican virtues, in what has been called ‘political pedagogy.’ In contrast to scholars of nationalism, who emphasize formal education, revolutionaries attempted to translate abstract ideas of equality and liberty into palpable representations that would inundate everyday life, thereby serving as pedagogical tools. Material culture and everyday life became state apparatuses not just for winning over citizens’ hearts and minds, but for influencing the very formation of the citizen and their innermost ‘self.’ This paper argues that nationalism began in 1789, when ‘the self’ became a political concern and its formation a state project for cultivating political legitimacy. By broadening the meaning of ‘political pedagogy,’ this study brings together scholarship on nationalism with cultural history, thereby highlighting nations and nationalism as banal, palpable, quotidian phenomena and historicizing the complex emergence of ‘modern nationalism.’ Moreover, because the contemporary view of material culture and pedagogy was highly gendered, this study shows the role of culture in the development of a homosocial, male-dominated public sphere in the 19th century. The legacy of the French Revolution’s concern with culture thus persists as much in our vocabulary for political expression as it does in the material world, remaining deeply embedded in everyday day life as a crucial, nearly-invisible, component of nationalism.Keywords: French Revolution, nationalism, political culture, material culture
Procedia PDF Downloads 1411154 Creative Resolutions to Intercultural Conflicts: The Joint Effects of International Experience and Cultural Intelligence
Authors: Thomas Rockstuhl, Soon Ang, Kok Yee Ng, Linn Van Dyne
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Intercultural interactions are often challenging and fraught with conflicts. To shed light on how to interact effectively across cultures, academics and practitioners alike have advanced a plethora of intercultural competence models. However, the majority of this work has emphasized distal outcomes, such as job performance and cultural adjustment, rather than proximal outcomes, such as how individuals resolve inevitable intercultural conflicts. As a consequence, the processes by which individuals negotiate challenging intercultural conflicts are not well understood. The current study advances theorizing on intercultural conflict resolution by exploring antecedents of how people resolve intercultural conflicts. To this end, we examine creativity – the generation of novel and useful ideas – in the context of resolving cultural conflicts in intercultural interactions. Based on the dual-identity theory of creativity, we propose that individuals with greater international experience will display greater creativity and that the relationship is accentuated by individual’s cultural intelligence. Two studies test these hypotheses. The first study comprises 84 senior university students, drawn from an international organizational behavior course. The second study replicates findings from the first study in a sample of 89 executives from eleven countries. Participants in both studies provided protocols of their strategies for resolving two intercultural conflicts, as depicted in two multimedia-vignettes of challenging intercultural work-related interactions. Two research assistants, trained in intercultural management but blind to the study hypotheses, coded all strategies for their novelty and usefulness following scoring procedures for creativity tasks. Participants also completed online surveys of demographic background information, including their international experience, and cultural intelligence. Hierarchical linear modeling showed that surprisingly, while international experience is positively associated with usefulness, it is unrelated to novelty. Further, a person’s cultural intelligence strengthens the positive effect of international experience on usefulness and mitigates the effect of international experience on novelty. Theoretically, our findings offer an important theoretical extension to the dual-identity theory of creativity by identifying cultural intelligence as an important individual difference moderator that qualifies the relationship between international experience and creative conflict resolution. In terms of novelty, individuals higher in cultural intelligence seem less susceptible to rigidity effects of international experiences. Perhaps they are more capable of assessing which aspects of culture are relevant and apply relevant experiences when they brainstorm novel ideas. For utility, individuals high in cultural intelligence are better able to leverage on their international experience to assess the viability of their ideas because their richer and more organized cultural knowledge structure allows them to assess possible options more efficiently and accurately. In sum, our findings suggest that cultural intelligence is an important and promising intercultural competence that fosters creative resolutions to intercultural conflicts. We hope that our findings stimulate future research on creativity and conflict resolution in intercultural contexts.Keywords: cultural Intelligence, intercultural conflict, intercultural creativity, international experience
Procedia PDF Downloads 1481153 Lignin Valorization: Techno-Economic Analysis of Three Lignin Conversion Routes
Authors: Iris Vural Gursel, Andrea Ramirez
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Effective utilization of lignin is an important mean for developing economically profitable biorefineries. Current literature suggests that large amounts of lignin will become available in second generation biorefineries. New conversion technologies will, therefore, be needed to carry lignin transformation well beyond combustion to produce energy, but towards high-value products such as chemicals and transportation fuels. In recent years, significant progress on catalysis has been made to improve transformation of lignin, and new catalytic processes are emerging. In this work, a techno-economic assessment of two of these novel conversion routes and comparison with more established lignin pyrolysis route were made. The aim is to provide insights into the potential performance and potential hotspots in order to guide the experimental research and ease the commercialization by early identifying cost drivers, strengths, and challenges. The lignin conversion routes selected for detailed assessment were: (non-catalytic) lignin pyrolysis as the benchmark, direct hydrodeoxygenation (HDO) of lignin and hydrothermal lignin depolymerisation. Products generated were mixed oxygenated aromatic monomers (MOAMON), light organics, heavy organics, and char. For the technical assessment, a basis design followed by process modelling in Aspen was done using experimental yields. A design capacity of 200 kt/year lignin feed was chosen that is equivalent to a 1 Mt/y scale lignocellulosic biorefinery. The downstream equipment was modelled to achieve the separation of the product streams defined. For determining external utility requirement, heat integration was considered and when possible gasses were combusted to cover heating demand. The models made were used in generating necessary data on material and energy flows. Next, an economic assessment was carried out by estimating operating and capital costs. Return on investment (ROI) and payback period (PBP) were used as indicators. The results of the process modelling indicate that series of separation steps are required. The downstream processing was found especially demanding in the hydrothermal upgrading process due to the presence of significant amount of unconverted lignin (34%) and water. Also, external utility requirements were found to be high. Due to the complex separations, hydrothermal upgrading process showed the highest capital cost (50 M€ more than benchmark). Whereas operating costs were found the highest for the direct HDO process (20 M€/year more than benchmark) due to the use of hydrogen. Because of high yields to valuable heavy organics (32%) and MOAMON (24%), direct HDO process showed the highest ROI (12%) and the shortest PBP (5 years). This process is found feasible with a positive net present value. However, it is very sensitive to the prices used in the calculation. The assessments at this stage are associated with large uncertainties. Nevertheless, they are useful for comparing alternatives and identifying whether a certain process should be given further consideration. Among the three processes investigated here, the direct HDO process was seen to be the most promising.Keywords: biorefinery, economic assessment, lignin conversion, process design
Procedia PDF Downloads 2611152 Role of Obama's Administration Counter-Terrorism Strategies towards Pakistan
Authors: Ahmed Bux Jamali
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The purpose of this study is to examine and evaluate the overall counterterrorism cooperation during Obama Administration towards Pakistan. It aims and focuses on the performances and measures taken by United States of America during President Obama in office in order to eradicate terrorism from Pakistan. Being a grave national security threat, terrorism played a disastrous role in the domestic peace and stability of both countries. For the sake of curbing this menace in South Asia in general and Pakistan in particular, the role of Obama Administration is viable and results-oriented despite major ups and downs in Pakistan U.S Relations during that period of time. Obama administration formulated policies when he comes to office in 2009 by looking at the already efforts done by Bush Administration to counterterrorism from Pakistan. Obama’s foreign policy was revolving around defense and diplomacy when it comes to dealing with Pakistan. The concept of smart power was indeed a core principle of Obama’s administration to gain the strategic objectives in Pakistan. Obama’s strategies in terms of providing military aid packages and various assistance programs, working on institutional building and strengthening the economy helped Pakistan in strengthening the military capabilities to go for militant operation in the safe havens area in the tribal areas of Pakistan. It further helped building institutional mechanism in the governmental policies to counter terrorism and militancy. The training of combat forces, artillery, and equipment provided by US proved fatal for the militant terrorist organizations seeking hideouts in the tribal areas of Pakistan. Resultantly, many top leaders of al Qaeda and many affiliated militant groups were captured and given to US as well. Despite many ups and downs in the bilateral relations on various domestic and international issues, both countries didn’t compromise the elimination of terrorist phenomena from Pakistan which was indeed a great success of the Obama administration’s counterterrorism and counterinsurgency strategies in the long run.Keywords: counterterrorism cooperation, national security strategy, Obama administration, Pakistan-US relations
Procedia PDF Downloads 1801151 Impact of Water Storage Structures on Groundwater Recharge in Jeloula Basin, Central Tunisia
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An attempt has been made to examine the effect of water storage structures on groundwater recharge in a semi-arid agroclimatic setting in Jeloula Basin (Central Tunisia). In this area, surface water in rivers is seasonal, and therefore groundwater is the perennial source of water supply for domestic and agricultural purposes. Three pumped storage water power plants (PSWPP) have been built to increase the overall water availability in the basin and support agricultural livelihoods of rural smallholders. The scale and geographical dispersion of these multiple lakes restrict the understanding of these coupled human-water systems and the identification of adequate strategies to support riparian farmers. In the present review, hydrochemistry and isotopic tools were combined to get an insight into the processes controlling mineralization and recharge conditions in the investigated aquifer system. This study showed a slight increase in the groundwater level, especially after the artificial recharge operations and a decline when the water volume moves down during drought periods. Chemical data indicate that the main sources of salinity in the waters are related to water-rock interactions. Data inferred from stable isotopes in groundwater samples indicated recharge with modern rainfall. The investigated surface water samples collected from the PSWPP are affected by a significant evaporation and reveal large seasonal variations, which could be controlled by the water volume changes in the open surface reservoirs and the meteorological conditions during evaporation, condensation, and precipitation. The geochemical information is comparable to the isotopic results and illustrates that the chemical and isotopic signatures of reservoir waters differ clearly from those of groundwaters. These data confirm that the contribution of the artificial recharge operations from the PSWPP is very limited.Keywords: Jeloula basin, recharge, hydrochemistry, isotopes
Procedia PDF Downloads 1521150 Development of Innovative Nuclear Fuel Pellets Using Additive Manufacturing
Authors: Paul Lemarignier, Olivier Fiquet, Vincent Pateloup
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In line with the strong desire of nuclear energy players to have ever more effective products in terms of safety, research programs on E-ATF (Enhanced-Accident Tolerant Fuels) that are more resilient, particularly to the loss of coolant, have been launched in all countries with nuclear power plants. Among the multitude of solutions being developed internationally, carcinoembryonic antigen (CEA) and its partners are investigating a promising solution, which is the realization of CERMET (CERamic-METal) type fuel pellets made of a matrix of fissile material, uranium dioxide UO2, which has a low thermal conductivity, and a metallic phase with a high thermal conductivity to improve heat evacuation. Work has focused on the development by powder metallurgy of micro-structured CERMETs, characterized by networks of metallic phase embedded in the UO₂ matrix. Other types of macro-structured CERMETs, based on concepts proposed by thermal simulation studies, have been developed with a metallic phase with a specific geometry to optimize heat evacuation. This solution could not be developed using traditional processes, so additive manufacturing, which revolutionizes traditional design principles, is used to produce these innovative prototype concepts. At CEA Cadarache, work is first carried out on a non-radioactive surrogate material, alumina, in order to acquire skills and to develop the equipment, in particular the robocasting machine, an additive manufacturing technique selected for its simplicity and the possibility of optimizing the paste formulations. A manufacturing chain was set up, with the pastes production, the 3D printing of pellets, and the associated thermal post-treatment. The work leading to the first elaborations of macro-structured alumina/molybdenum CERMETs will be presented. This work was carried out with the support of Framatome and EdF.Keywords: additive manufacturing, alumina, CERMET, molybdenum, nuclear safety
Procedia PDF Downloads 771149 Improvements in Transient Testing in The Transient REActor Test (TREAT) with a Choice of Filter
Authors: Harish Aryal
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The safe and reliable operation of nuclear reactors has always been one of the topmost priorities in the nuclear industry. Transient testing allows us to understand the time-dependent behavior of the neutron population in response to either a planned change in the reactor conditions or unplanned circumstances. These unforeseen conditions might occur due to sudden reactivity insertions, feedback, power excursions, instabilities, and accidents. To study such behavior, we need transient testing, which is like car crash testing, to estimate the durability and strength of a car design. In nuclear designs, such transient testing can simulate a wide range of accidents due to sudden reactivity insertions and helps to study the feasibility and integrity of the fuel to be used in certain reactor types. This testing involves a high neutron flux environment and real-time imaging technology with advanced instrumentation with appropriate accuracy and resolution to study the fuel slumping behavior. With the aid of transient testing and adequate imaging tools, it is possible to test the safety basis for reactor and fuel designs that serves as a gateway in licensing advanced reactors in the future. To that end, it is crucial to fully understand advanced imaging techniques both analytically and via simulations. This paper presents an innovative method of supporting real-time imaging of fuel pins and other structures during transient testing. The major fuel-motion detection device that is studied in this dissertation is the Hodoscope which requires collimators. This paper provides 1) an MCNP model and simulation of a Transient Reactor Test (TREAT) core with a central fuel element replaced by a slotted fuel element that provides an open path between test samples and a hodoscope detector and 2) a choice of good filter to improve image resolution.Keywords: hodoscope, transient testing, collimators, MCNP, TREAT, hodogram, filters
Procedia PDF Downloads 771148 The Effectiveness of Copegus (Ribavirin) Placed in a Field of Unexplored Properties of Low-Level Laser Radiation in the Treatment of Long-Covid Syndrome
Authors: Naylya Djumaeva
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Since the end of 2019, the world has been shaken by an infection that has claimed the lives of more than six and a half million patients. Currently, SARS-CoV-2 not only causes acute damage but has long-term consequences affecting every organ and has brought a wave of a new chronic disabling condition called Long-Covid..This preliminary study describes an application of un-explored properties of low-level laser radiation with laser- light emitter in the field of which is placed Copegus (Ribavirin) with the aim of treatment of patients with Long-Covid syndrome. The difference from the traditional use of the drug is that Copegus was not prescribed to the patient by the traditional method - orally or intravenously, and the medicinal properties of the drug were introduced into the patient’s body using the un-explored properties of low-power laser radiation. Ninety eight patients with Long- Covid syndrome were observed. The obtained findings suggest that under the influence of the field formed into the laser- light emitter with a Copegus placed inside the field, the remote transfer of pharmacological properties of Сopegus occurs. Conclusions about the produced effect of exposure were made based on improvement in the condition of patients, the disappearance of complaints, and positive changes in various diagnostic tests performed by the patients. Biography: Djumaeva N completed her PhD from the Institute of Epidemiology, Microbiology and Infectious Diseases in 2000. In her dissertation work devoted to the treatment of patients with chronic hepatitis B virus infection, she presented data on the possible influence of Complex Homeopathic Preparations on the organization of bound intracellular water in the cells of the body. She is the Consultant (Neurologist) at the Scientific-Research Institute for Virology, Uzbekistan, and an expert in “medicament testing” method (30 years). She has published 43 papers, including 2 patents.Keywords: long covid, low level laser, copegus, laser- light emmiter
Procedia PDF Downloads 951147 Analysis of the Potential of Biomass Residues for Energy Production and Applications in New Materials
Authors: Sibele A. F. Leite, Bernno S. Leite, José Vicente H. D´Angelo, Ana Teresa P. Dell’Isola, Julio CéSar Souza
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The generation of bioenergy is one of the oldest and simplest biomass applications and is one of the safest options for minimizing emissions of greenhouse gasses and replace the use of fossil fuels. In addition, the increasing development of technologies for energy biomass conversion parallel to the advancement of research in biotechnology and engineering has enabled new opportunities for exploitation of biomass. Agricultural residues offer great potential for energy use, and Brazil is in a prominent position in the production and export of agricultural products such as banana and rice. Despite the economic importance of the growth prospects of these activities and the increasing of the agricultural waste, they are rarely explored for energy and production of new materials. Brazil products almost 10.5 million tons/year of rice husk and 26.8 million tons/year of banana stem. Thereby, the aim of this study was to analysis the potential of biomass residues for energy production and applications in new materials. Rice husk (specify the type) and banana stem (specify the type) were characterized by physicochemical analyses using the following parameters: organic carbon, nitrogen (NTK), proximate analyses, FT-IR spectroscopy, thermogravimetric analyses (TG), calorific values and silica content. Rice husk and banana stem presented attractive superior calorific (from 11.5 to 13.7MJ/kg), and they may be compared to vegetal coal (21.25 MJ/kg). These results are due to the high organic matter content. According to the proximate analysis, biomass has high carbon content (fixed and volatile) and low moisture and ash content. In addition, data obtained by Walkley–Black method point out that most of the carbon present in the rice husk (50.5 wt%) and in banana stalk (35.5 wt%) should be understood as organic carbon (readily oxidizable). Organic matter was also detected by Kjeldahl method which gives the values of nitrogen (especially on the organic form) for both residues: 3.8 and 4.7 g/kg of rice husk and banana stem respectively. TG and DSC analyses support the previous results, as they can provide information about the thermal stability of the samples allowing a correlation between thermal behavior and chemical composition. According to the thermogravimetric curves, there were two main stages of mass-losses. The first and smaller one occurred below 100 °C, which was suitable for water losses and the second event occurred between 200 and 500 °C which indicates decomposition of the organic matter. At this broad peak, the main loss was between 250-350 °C, and it is because of sugar decomposition (components readily oxidizable). Above 350 °C, mass loss of the biomass may be associated with lignin decomposition. Spectroscopic characterization just provided qualitative information about the organic matter, but spectra have shown absorption bands around 1030 cm-1 which may be identified as species containing silicon. This result is expected for the rice husk and deserves further investigation to the stalk of banana, as it can bring a different perspective for this biomass residue.Keywords: rice husk, banana stem, bioenergy, renewable feedstock
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