Search results for: low non-renewable energy consumption
Commenced in January 2007
Frequency: Monthly
Edition: International
Paper Count: 10317

Search results for: low non-renewable energy consumption

3387 The Design, Control and Dynamic Performance of an Interior Permanent Magnet Synchronous Generator for Wind Power System

Authors: Olusegun Solomon

Abstract:

This paper describes the concept for the design and maximum power point tracking control for an interior permanent magnet synchronous generator wind turbine system. Two design concepts are compared to outline the effect of magnet design on the performance of the interior permanent magnet synchronous generator. An approximate model that includes the effect of core losses has been developed for the machine to simulate the dynamic performance of the wind energy system. An algorithm for Maximum Power Point Tracking control is included to describe the process for maximum power extraction.

Keywords: permanent magnet synchronous generator, wind power system, wind turbine

Procedia PDF Downloads 221
3386 Shale Gas and Oil Resource Assessment in Middle and Lower Indus Basin of Pakistan

Authors: Amjad Ali Khan, Muhammad Ishaq Saqi, Kashif Ali

Abstract:

The focus of hydrocarbon exploration in Pakistan has been primarily on conventional hydrocarbon resources. Directorate General Petroleum Concessions (DGPC) has taken the lead on the assessment of indigenous unconventional oil and gas resources, which has resulted in a ‘Shale Oil/Gas Resource Assessment Study’ conducted with the help of USAID. This was critically required in the energy-starved Pakistan, where the gap between indigenous oil & gas production and demand continues to widen for a long time. Exploration & exploitation of indigenous unconventional resources of Pakistan have become vital to meet our energy demand and reduction of oil and gas import bill of the country. This study has attempted to bridge a critical gap in geological information about the potential of shale gas & oil in Pakistan in the four formations, i.e., Sembar, Lower Goru, Ranikot and Ghazij in the Middle and Lower Indus Basins, which were selected for the study as for resource assessment for shale gas & oil. The primary objective of the study was to estimate and establish shale oil/gas resource assessment of the study area by carrying out extensive geological analysis of exploration, appraisal and development wells drilled in the Middle and Lower Indus Basins, along with identification of fairway(s) and sweet spots in the study area. The Study covers the Lower parts of the Middle Indus basins located in Sindh, southern Punjab & eastern parts of the Baluchistan provinces, with a total sedimentary area of 271,795 km2. Initially, 1611 wells were reviewed, including 1324 wells drilled through different shale formations. Based on the availability of required technical data, a detailed petrophysical analysis of 124 wells (21 Confidential & 103 in the public domain) has been conducted for the shale gas/oil potential of the above-referred formations. The core & cuttings samples of 32 wells and 33 geochemical reports of prospective Shale Formations were available, which were analyzed to calibrate the results of petrophysical analysis with petrographic/ laboratory analyses to increase the credibility of the Shale Gas Resource assessment. This study has identified the most prospective intervals, mainly in Sembar and Lower Goru Formations, for shale gas/oil exploration in the Middle and Lower Indus Basins of Pakistan. The study recommends seven (07) sweet spots for undertaking pilot projects, which will enable to evaluate of the actual production capability and production sustainability of shale oil/gas reservoirs of Pakistan for formulating future strategies to explore and exploit shale/oil resources of Pakistan including fiscal incentives required for developing shale oil/gas resources of Pakistan. Some E&P Companies are being persuaded to make a consortium for undertaking pilot projects that have shown their willingness to participate in the pilot project at appropriate times. The location for undertaking the pilot project has been finalized as a result of a series of technical sessions by geoscientists of the potential consortium members after the review and evaluation of available studies.

Keywords: conventional resources, petrographic analysis, petrophysical analysis, unconventional resources, shale gas & oil, sweet spots

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3385 Electrochemical Studies of Si, Si-Ge- and Ge-Air Batteries

Authors: R. C. Sharma, Rishabh Bansal, Prajwal Menon, Manoj K. Sharma

Abstract:

Silicon-air battery is highly promising for electric vehicles due to its high theoretical energy density (8470 Whkg⁻¹) and its discharge products are non-toxic. For the first time, pure silicon and germanium powders are used as anode material. Nickel wire meshes embedded with charcoal and manganese dioxide powder as cathode and concentrated potassium hydroxide is used as electrolyte. Voltage-time curves have been presented in this study for pure silicon and germanium powder and 5% and 10% germanium with silicon powder. Silicon powder cell assembly gives a stable voltage of 0.88 V for ~20 minutes while Si-Ge provides cell voltage of 0.80-0.76 V for ~10-12 minutes, and pure germanium cell provides cell voltage 0.80-0.76 V for ~30 minutes. The cell voltage is higher for concentrated (10%) sodium hydroxide solution (1.08 V) and it is stable for ~40 minutes. A sharp decrease in cell voltage beyond 40 min may be due to rapid corrosion.

Keywords: Silicon-air battery, Germanium-air battery, voltage-time curve, open circuit voltage, Anodic corrosion

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3384 Anti-Inflammatory Effect of Myristic Acid through Inhibiting NF-κB and MAPK Signaling Pathways in Lipopolysaccharide-Stimulated RAW 264.7 Macrophage Cells

Authors: Hyun Ji Hyun, Hyo Sun Suh, Min Kook Kim, Yong Chan Kwon, Byung-Mu Lee

Abstract:

Scope: This study is focused on the effect of myristic acid on LPS-induced inflammation in RAW 264.7 macrophage cells. Methods and results: For the experiment, RAW 264.7 mouse macrophage cell line was used. Results showed that treatment with myristic acid can attenuate LPS-induced inflammation. Moreover, myristic acid significantly suppressed expression of inflammatory mediators and down-regulating UVB-induced intracellular ROS generation. Furthermore, myristic acid reduced the expression of NF-κB by inhibiting degradation of IκB-α and ERK, JNK, and p38 pathways by inhibiting phosphorylation in RAW 264.7 macrophage cells. Conclusion: Overall, these data suggest that the myristic acid could reduce LPS-induced inflammation. Acknowledgment: This research was supported by the Ministry of Trade, Industry & Energy(MOTIE), Korea Institute for Advancement of Technology(KIAT) through the Encouragement Program for The Industries of Economic Cooperation Region

Keywords: anti-inflammation, myristic acid, ROS, ultraviolet light

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3383 Improved Active Constellation Extension for the PAPR Reduction of FBMC-OQAM Signals

Authors: Mounira Laabidi, Rafik Zayani, Ridha Bouallegue, Daniel Roviras

Abstract:

The Filter Bank multicarrier with Offset Quadrature Amplitude Modulation (FBMC-OQAM) has been introduced to overcome the poor spectral characteristics and the waste in both bandwidth and energy caused by the use of the cyclic prefix. However, the FBMC-OQAM signals suffer from the high Peak to Average Power Ratio (PAPR) problem. Due to the overlapping structure of the FBMC-OQAM signals, directly applying the PAPR reduction schemes conceived for the OFDM one turns out to be ineffective. In this paper, we address the problem of PAPR reduction for FBMC-OQAM systems by suggesting a new scheme based on an improved version of Active Constellation Extension scheme (ACE) of OFDM. The proposed scheme, named Rolling Window ACE, takes into consideration the overlapping naturally emanating from the FBMC-OQAM signals.

Keywords: ACE, FBMC, OQAM, OFDM, PAPR, rolling-window

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3382 Sustainability: Effect of Earthquake in Micro Hydro Sector, a Case Study of Micro Hydro Projects in Northern Part of Kavre District, Nepal

Authors: Ram Bikram Thapa, Ganesh Lama

Abstract:

The Micro Hydro is one of the successful technology in Rural Nepal. Kavre is one of the pioneer district of sustainability of Micro Hydro Projects. A total of 30 Micro Hydro projects have been constructed with producing 700 KW of energy in northern side of the Kavre district. This study shows that 67% of projects have been affected by devastating earthquake in April and May, 2015. Out of them 23% are completely damaged. Most of the structures are failure like Penstock 71%, forebay 21%, powerhouse 7% have been completely damaged and 91% Canal & 44% Intake structures have been partially damaged by the earthquake. This paper empathizes that the engineering design is the vital component for sustainability of Micro Hydro Projects. This paper recommended that technicians should be considered the safety factor of earthquake and provision of disaster recovery fund during design of Micro Hydro Projects.

Keywords: micro hydro, earthquake, structural failure, sustainability

Procedia PDF Downloads 348
3381 Synthesis of Highly Valuable Fuel Fractions from Waste Date Seeds Oil

Authors: Farrukh Jamil, Ala'A H. Al-Muhtaseb, Lamya Al-Haj, Mohab A. Al-Hinai

Abstract:

Environmental problems and the security of energy supply have motivated the attention in the expansion of alternatives for fossil based fuels. Biomass has been recognized as a capable resource because it is plentifully available and in principle carbon dioxide neutral. Present study focuses on utilization date seeds oil for synthesizing high value fuels formulations such as green diesel and jet fuel. The hydrodeoxygenation of date seeds oil occurred to be highly efficient at following operating conditions temperature 300°C pressure 10bar with continuous stirring at 500 rpm. Products characterization revealed the efficiency of hydrodeoxygenation by formation of linear hydrocarbons (paraffin) in larger fraction. Based on the type of components in product oil it was calculated that maximum fraction lies within the range of green diesel 72.78 % then jet fuel 28.25 % by using Pt/C catalyst. It can be concluded that waste date seeds oil has potential to be used for obtaining high value products.

Keywords: date seeds, hydrodeoxygenation, paraffin, deoxygenation

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3380 Formation Flying Design Applied for an Aurora Borealis Monitoring Mission

Authors: Thais Cardoso Franco, Caio Nahuel Sousa Fagonde, Willer Gomes dos Santos

Abstract:

Aurora Borealis is an optical phenomenon composed of luminous events observed in the night skies in the polar regions resulting from disturbances in the magnetosphere due to the impact of solar wind particles with the Earth's upper atmosphere, channeled by the Earth's magnetic field, which causes atmospheric molecules to become excited and emit electromagnetic spectrum, leading to the display of lights in the sky. However, there are still different implications of this phenomenon under study: high intensity auroras are often accompanied by geomagnetic storms that cause blackouts on Earth and impair the transmission of signals from the Global Navigation Satellite Systems (GNSS). Auroras are also known to occur on other planets and exoplanets, so the activity is an indication of active space weather conditions that can aid in learning about the planetary environment. In order to improve understanding of the phenomenon, this research aims to design a satellite formation flying solution for collecting and transmitting data for monitoring aurora borealis in northern hemisphere, an approach that allows studying the event with multipoint data collection in a reduced time interval, in order to allow analysis from the beginning of the phenomenon until its decline. To this end, the ideal number of satellites, the spacing between them, as well as the ideal topology to be used will be analyzed. From an orbital study, approaches from different altitudes, eccentricities and inclinations will also be considered. Given that at large relative distances between satellites in formation, controllers tend to fail, a study on the efficiency of nonlinear adaptive control methods from the point of view of position maintenance and propellant consumption will be carried out. The main orbital perturbations considered in the simulation: non-homogeneity terrestrial, atmospheric drag, gravitational action of the Sun and the Moon, accelerations due to solar radiation pressure and relativistic effects.

Keywords: formation flying, nonlinear adaptive control method, aurora borealis, adaptive SDRE method

Procedia PDF Downloads 39
3379 Effect an Axial Magnetic Field in Co-rotating Flow Heated from Below

Authors: B. Mahfoud, A. Bendjagloli

Abstract:

The effect of an axial magnetic field on the flow produced by co-rotation of the top and bottom disks in a vertical cylindrical heated from below is numerically analyzed. The governing Navier-Stokes, energy, and potential equations are solved by using the finite-volume method. It was observed that the Reynolds number is increased, the axisymmetric basic state loses stability to circular patterns of axisymmetric vortices and spiral waves. In mixed convection case the axisymmetric mode disappears giving an asymmetric mode m=1. It was also found that the primary thresholds Recr corresponding to the modes m=1and 2, increase with increasing of the Hartmann number (Ha). Finally, stability diagrams have been established according to the numerical results of this investigation. These diagrams giving the evolution of the primary thresholds as a function of the Hartmann number for various values of the Richardson number.

Keywords: bifurcation, co-rotating end disks, magnetic field, stability diagrams, vortices

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3378 Design Parameters Optimization of a Gas Turbine with Exhaust Gas Recirculation: An Energy and Exergy Approach

Authors: Joe Hachem, Marianne Cuif-Sjostrand, Thierry Schuhler, Dominique Orhon, Assaad Zoughaib

Abstract:

The exhaust gas recirculation, EGR, implementation on gas turbines is increasingly gaining the attention of many researchers. This emerging technology presents many advantages, such as lowering the NOx emissions and facilitating post-combustion carbon capture as the carbon dioxide concentration in the cycle increases. As interesting as this technology may seem, the gas turbine, or its thermodynamic equivalent, the Brayton cycle, shows an intrinsic efficiency decrease with increasing EGR rate. In this paper, a thermodynamic model is presented to show the cycle efficiency decrease with EGR, alternative values of design parameters of both the pressure ratio (PR) and the turbine inlet temperature (TIT) are then proposed to optimize the cycle efficiency with different EGR rates. Results show that depending on the given EGR rate, both the design PR & TIT should be increased to compensate for the deficit in efficiency.

Keywords: gas turbines, exhaust gas recirculation, design parameters optimization, thermodynamic approach

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3377 Preparation of 3D Graphene with Microwave-Hydrothermal Assistance for Ultrahigh Performance of Capacitive Deionization

Authors: Wahid Dianbudiyanto, Shou Heng Liu

Abstract:

Capacitive deionization (CDI) is a prospective desalination technology, which can be operated at low voltage, low temperature and potentially consume low energy for brackish water desalination. To obtain the optimal electrosorption, an electrode should possess high electrical conductivity, large surface area, good wettability, highly mesoporous structure which provide efficient pathways for ion distribution. In this work, a 3D structure graphene was fabricated using hydrothermal method which is assisted with microwave treatments to form 3D rGO (3DG-Mw-Hyd). The prepared samples have excellent specific capacitance (189.2 F / g) and ultrahigh electrosorption capacity (30 mg/g) for the desalination of 500 mg / l NaCl. These results are superior to the electrode which is fabricated only using the hydrothermal method without microwave assistance (3DG-Hyd) and traditional reflux method. Physical characterizations such as SEM, TEM, and XRD have been used to study the property difference of the materials. The preliminary results show that 3DG-Mw-Hyd is one of the promising electrodes for CDI in the practical applications.

Keywords: capacitive deionization, graphene, microwave, hydrothermal, electrosorption

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3376 Advancements in Truss Design for High-Performance Facades and Roof System: A Structural Analysis

Authors: Milind Anurag

Abstract:

This study investigates cutting-edge truss design improvements, which are specifically adapted to satisfy the structural demands and difficulties associated with high-performance facades and roofs in modern architectural environments. With a growing emphasis on sustainability, energy efficiency, and eye-catching architectural aesthetics, the structural components that support these characteristics play an important part in attaining the right balance of form and function. The paper seeks to contribute to the evolution of truss design methods by combining data from these investigations, giving significant insights for architects, engineers, and researchers interested in the creation of high-performance building envelopes. The findings of this study are meant to inform future design standards and practices, promoting the development of structures that seamlessly integrate architectural innovation with structural robustness and environmental responsibility.

Keywords: truss design, high-performance, facades, finite element analysis, structural efficiency

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3375 Lignin Valorization: Techno-Economic Analysis of Three Lignin Conversion Routes

Authors: Iris Vural Gursel, Andrea Ramirez

Abstract:

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

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3374 Investigation of Interaction between Interferons and Polyethylene Glycol Using Molecular Dynamics Simulation

Authors: M. Dehestani, F. Kamali, M. Klantari Pour, L. Zeidabadi-Nejad

Abstract:

Chemical bonding between polyethylene glycol (PEG) with pharmaceutical proteins called pegylation is one of the most effective methods of improving the pharmacological properties. The covalent attachment of polyethylene glycol (PEG) to proteins will increase their pharmacologic properties. For the formation of a combination of pegylated protein should first be activated PEG and connected to the protein. Interferons(IFNs) are a family of cytokines which show antiviral effects in front of the biological and are responsible for setting safety system. In this study, the nature and properties of the interaction between active positions of IFNs and polyethylene glycol have been investigated using molecular dynamics simulation. The main aspect of this theoretical work focuses on the achievement of valuable data on the reaction pathways of PEG-IFNs and the transition state energy. Our results provide a new perspective on the interactions, chemical properties and reaction pathways between IFNs and PEG.

Keywords: interaction, interferons, molecular dynamics simulation, polyethylene glycol

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3373 Forecasting Direct Normal Irradiation at Djibouti Using Artificial Neural Network

Authors: Ahmed Kayad Abdourazak, Abderafi Souad, Zejli Driss, Idriss Abdoulkader Ibrahim

Abstract:

In this paper Artificial Neural Network (ANN) is used to predict the solar irradiation in Djibouti for the first Time that is useful to the integration of Concentrating Solar Power (CSP) and sites selections for new or future solar plants as part of solar energy development. An ANN algorithm was developed to establish a forward/reverse correspondence between the latitude, longitude, altitude and monthly solar irradiation. For this purpose the German Aerospace Centre (DLR) data of eight Djibouti sites were used as training and testing in a standard three layers network with the back propagation algorithm of Lavenber-Marquardt. Results have shown a very good agreement for the solar irradiation prediction in Djibouti and proves that the proposed approach can be well used as an efficient tool for prediction of solar irradiation by providing so helpful information concerning sites selection, design and planning of solar plants.

Keywords: artificial neural network, solar irradiation, concentrated solar power, Lavenberg-Marquardt

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3372 A Theoretical Overview of Thermoluminescence

Authors: Sadhana Agrawal, Tarkeshwari Verma, Shmbhavi Katyayan

Abstract:

The magnificently accentuating phenomenon of luminescence has gathered a lot of attentions from last few decades. Probably defined as the one involving emission of light from certain kinds of substances on absorbing various energies in the form of external stimulus, the phenomenon claims a versatile pertinence. First observed and reported in an extract of Ligrium Nephriticum by Monards, the phenomenon involves turning of crystal clear water into colorful fluid when comes in contact with the special wood. In words of Sir G.G. Stokes, the phenomenon actually involves three different techniques – absorption, excitation and emission. With variance in external stimulus, the corresponding luminescence phenomenon is obtained. Here, this paper gives a concise discussion of thermoluminescence which is one of the types of luminescence obtained when the external stimulus is given in form of heat energy. A deep insight of thermoluminescence put forward a qualitative analysis of various parameters such as glow curves peaks, trap depth, frequency factors and order of kinetics.

Keywords: frequency factor, glow curve peaks, thermoluminescence, trap depth

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3371 POSS as Modifiers and Additives for Elastomer Composites

Authors: Anna Strąkowska, Marian Zaborski

Abstract:

The studies were focused on POSS application with methylvinylsilicone rubber (MVQ). The obtained results indicate that they can be successfully incorporated into silica-filled rubbers as modifying agents since they enhance cross-link density and improve most properties of the resulting network. It is also worth noting that the incorporation of POSS molecules resulted in stabilizing effect against adverse changes induced by the climatic, ozone or UV ageing of the rubbers. Furthermore, we obtained interesting results of rubbers surface modification using POSS functionalised with halogen groups (Cl, F, and Br). As the results, surface energy of the elastomeric composites and their hydrophobicity increased, barrier properties improved and thermal stability increased as well. Additionally, the studies with silicone rubber and POSS containing acidic and alkaline groups revealed composites with self-healing properties. The observed effects strictly depend on a kind and quantity of functional groups present in angles of POSS cages.

Keywords: elastomeric composites, POSS, properties modyfication, silicone rubber

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3370 A Comparative Density Functional Theory Study of Hydrocarbon Combustion on Metal Surfaces

Authors: Abas Mohsenzadeh, Mina Arya, Kim Bolton

Abstract:

Catalytic combustion of hydrocarbons is an important technology developed to produce energy with minimum pollutant formation. The catalyst plays a key role in this process which operates at lower temperatures compared to conventional flame combustion. The energetics of the direct combustion of hydrocarbons (CH → C + H) on a series of metal surfaces including Ag, Au, Al, Cu, Rh, Pt, Pd, Ni, Fe and Co were investigated using density functional theory (DFT). Brønsted-Evans-Polanyi (BEP) and transition state scaling (TSS) correlations were proposed based on DFT calculations on the Ag, Au, Al, Cu, Rh, Pt and Pd surfaces. These correlations were then used to estimate the energetics on Fe, Ni and Co surfaces. Results showed that the estimated reaction and activation energies by BEP and TSS correlations on Fe, Ni and Co surfaces are in an excellent agreement with those obtained by DFT calculations. Therefore these correlations can be efficiently used to predict energetics of similar reactions on these surfaces without doing computationally costly transition state calculations. It was found that the activation barrier for CH dissociation follows the order Ag ˃ Au ˃ Al ˃ Cu ˃ Pt ˃ Pd ˃ Ni > Co > Rh > Fe. Also, BEP (with R2 value of 0.96) and TSS correlations (with R2 value of 0.99) support the results.

Keywords: BEP, DFT, hydrocarbon combustion, metal surfaces, TSS

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3369 Utilizing AI Green Grader Scope to Promote Environmental Responsibility Among University Students

Authors: Tarek Taha Kandil

Abstract:

In higher education, the use of automated grading systems is on the rise, automating the assessment of students' work and providing practical feedback. Sustainable Grader Scope addresses the environmental impact of these computational tasks. This system uses an AI-powered algorithm and is designed to minimize grading process emissions. It reduces carbon emissions through energy-efficient computing and carbon-conscious scheduling. Students submit their computational workloads to the system, which evaluates submissions using containers and a distributed infrastructure. A carbon-conscious scheduler manages workloads across global campuses, optimizing emissions using real-time carbon intensity data. This ensures the university stays within government-set emission limits while tracking and reducing its carbon footprint.

Keywords: sustainability, green graders, digital sustainable grader scope, environmental responsibility; higher education.

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3368 Two-Dimensional Modeling of Spent Nuclear Fuel Using FLUENT

Authors: Imane Khalil, Quinn Pratt

Abstract:

In a nuclear reactor, an array of fuel rods containing stacked uranium dioxide pellets clad with zircalloy is the heat source for a thermodynamic cycle of energy conversion from heat to electricity. After fuel is used in a nuclear reactor, the assemblies are stored underwater in a spent nuclear fuel pool at the nuclear power plant while heat generation and radioactive decay rates decrease before it is placed in packages for dry storage or transportation. A computational model of a Boiling Water Reactor spent fuel assembly is modeled using FLUENT, the computational fluid dynamics package. Heat transfer simulations were performed on the two-dimensional 9x9 spent fuel assembly to predict the maximum cladding temperature for different input to the FLUENT model. Uncertainty quantification is used to predict the heat transfer and the maximum temperature profile inside the assembly.

Keywords: spent nuclear fuel, conduction, heat transfer, uncertainty quantification

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3367 Identification of the Usage of Some Special Places in the Prehistoric Site of Tapeh Zagheh through Multi-Elemental Chemical Analysis of the Soil Samples

Authors: Iraj Rezaei, Kamal Al Din Niknami

Abstract:

Tapeh Zagheh is an important prehistoric site located in the central plateau of Iran, which has settlement layers of the Neolithic and Chalcolithic periods. For this research, 38 soil samples were collected from different parts of the site, as well as two samples from its outside as witnesses. Then the samples were analyzed by XRF. The purpose of this research was to identify some places with special usage for human activities in Tapeh Zagheh by measuring the amount of some special elements in the soil. The result of XRF analysis shows a significant amount of P and K in samples No.3 (fourth floor) and No.4 (third floor), probably due to certain activities such as food preparation and consumption. Samples No.9 and No.10 can be considered suitable examples of the hearths of the prehistoric period in the central plateau of Iran. The color of these samples was completely darkened due to the presence of ash, charcoal, and burnt materials. According to the XRF results, the soil of these hearths has very high amounts of elements such as P, Ca, Mn, S, K, and significant amounts of Ti, Fe, and Na. In addition, the elemental composition of sample No. 14, which was taken from a home waster, also has very high amounts of P, Mn, Mg, Ti, and Fe and high amounts of K and Ca. Sample No. 11, which is related to soil containing large amounts of waster of the kiln, along with a very strong increase in Cl and Na, the amount of elements such as K, Mg, and S has also increased significantly. It seems that the reason for the increase of elements such as Ti and Fe in some Tapeh Zagheh floors (for example, samples number 1, 2, 3, 4, 5) was the use of materials such as ocher mud or fire ash in the composition of these floors. Sample No. 13, which was taken from an oven located in the FIX trench, has very high amounts of Mn, Ti, and Fe and high amounts of P and Ca. Sample No. 15, which is related to House No. VII (probably related to a pen or a place where animals were kept) has much more phosphate compared to the control samples, which is probably due to the addition of animal excrement and urine to the soil. Sample No. 29 was taken from the north of the industrial area of Zagheh village (place of pottery kilns). The very low amount of index elements in sample No. 29 shows that the industrial activities did not extend to the mentioned point, and therefore, the range of this point can be considered as the boundary between the residential part of the Zagheh village and its industrial part.

Keywords: prehistory, multi-elemental analysis, Tapeh Zagheh, XRF

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3366 Preparation, Characterization and Photocatalytic Activity of a New Noble Metal Modified TiO2@SrTiO3 and SrTiO3 Photocatalysts

Authors: Ewelina Grabowska, Martyna Marchelek

Abstract:

Among the various semiconductors, nanosized TiO2 has been widely studied due to its high photosensitivity, low cost, low toxicity, and good chemical and thermal stability. However, there are two main drawbacks to the practical application of pure TiO2 films. One is that TiO2 can be induced only by ultraviolet (UV) light due to its intrinsic wide bandgap (3.2 eV for anatase and 3.0 eV for rutile), which limits its practical efficiency for solar energy utilization since UV light makes up only 4-5% of the solar spectrum. The other is that a high electron-hole recombination rate will reduce the photoelectric conversion efficiency of TiO2. In order to overcome the above drawbacks and modify the electronic structure of TiO2, some semiconductors (eg. CdS, ZnO, PbS, Cu2O, Bi2S3, and CdSe) have been used to prepare coupled TiO2 composites, for improving their charge separation efficiency and extending the photoresponse into the visible region. It has been proved that the fabrication of p-n heterostructures by combining n-type TiO2 with p-type semiconductors is an effective way to improve the photoelectric conversion efficiency of TiO2. SrTiO3 is a good candidate for coupling TiO2 and improving the photocatalytic performance of the photocatalyst because its conduction band edge is more negative than TiO2. Due to the potential differences between the band edges of these two semiconductors, the photogenerated electrons transfer from the conduction band of SrTiO3 to that of TiO2. Conversely, the photogenerated electrons transfer from the conduction band of SrTiO3 to that of TiO2. Then the photogenerated charge carriers can be efficiently separated by these processes, resulting in the enhancement of the photocatalytic property in the photocatalyst. Additionally, one of the methods for improving photocatalyst performance is addition of nanoparticles containing one or two noble metals (Pt, Au, Ag and Pd) deposited on semiconductor surface. The mechanisms were proposed as (1) the surface plasmon resonance of noble metal particles is excited by visible light, facilitating the excitation of the surface electron and interfacial electron transfer (2) some energy levels can be produced in the band gap of TiO2 by the dispersion of noble metal nanoparticles in the TiO2 matrix; (3) noble metal nanoparticles deposited on TiO2 act as electron traps, enhancing the electron–hole separation. In view of this, we recently obtained series of TiO2@SrTiO3 and SrTiO3 photocatalysts loaded with noble metal NPs. using photodeposition method. The M- TiO2@SrTiO3 and M-SrTiO3 photocatalysts (M= Rh, Rt, Pt) were studied for photodegradation of phenol in aqueous phase under UV-Vis and visible irradiation. Moreover, in the second part of our research hydroxyl radical formations were investigated. Fluorescence of irradiated coumarin solution was used as a method of ˙OH radical detection. Coumarin readily reacts with generated hydroxyl radicals forming hydroxycoumarins. Although the major hydroxylation product is 5-hydroxycoumarin, only 7-hydroxyproduct of coumarin hydroxylation emits fluorescent light. Thus, this method was used only for hydroxyl radical detection, but not for determining concentration of hydroxyl radicals.

Keywords: composites TiO2, SrTiO3, photocatalysis, phenol degradation

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3365 Merchants’ Attitudes towards Tourism Development in Mahane Yehuda Market: A Case Study

Authors: Rotem Mashkov, Noam Shoval

Abstract:

In an age when a tourist’s gaze is more focused on the daily lives of locals, it is evident that local food markets are being rediscovered. Traditional urban markets succeed in reinventing themselves as a space for consumption, recreation, and culture, enabling authentic experiences and interpersonal interactions with the local culture. Alongside this, the pressure of tourism development may result in commercialization and retail gentrification to the point of losing the sense of local identity. The issue of finding a balance between tourism development and the preservation of unique local features is at the heart of this study and is being tested using the case of the Mahane Yehuda market in Jerusalem. The research question—how merchants respond to tourism development in the Mahane Yehuda food market— focuses on local traders, a group of players who are usually absent from the research arenas, although they influence tourism development as well as influenced by it. Three main research methods were integrated into this study. The first two methods, a survey of articles survey and comparative mapping of the business mix, were used to characterize the changes in the Mahane Yehuda market both consciously and physically. The third research method, involving in-depth interviews with merchants, was used to examine the traders' attitudes and responses to tourism development. The findings indicate that there has been a turnaround in the market image over the past decade and a half. Additionally, there has been a significant physical change in the business mix, reflected by a decline of 15% in the number of stalls selling food products and delicacies. The data from the interviews on the traders’ attitudes towards tourism development were inconclusive; there were disagreements among the traders about the economic contribution of tourism development in relation to their dependence on the tourism industry. However, there was a consensus on the need for authentic elements in the marketplace. The findings of the study also indicate a strong link between the merchants’ response to tourism development and their stall ownership status as the merchant could exercise their position in various ways depending on the possession type.

Keywords: business mix, Jerusalem, local food markets, Mahane Yehuda market, merchants’ attitude, ownership status, retail gentrification, tourism development, traditional urban markets

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3364 Eco-Infrastructures: A Multidimensional System Approach for Urban Ecology

Authors: T. A. Mona M. Salem, Ali F. Bakr

Abstract:

Given the potential devastation associated with future climate change related disasters, it is vital to change the way we build and manage our cities, through new strategies to reconfigure them and their infrastructures in ways that help secure their reproduction. This leads to a kaleidoscopic view of the city that recognizes the interrelationships of energy, water, transportation, and solid waste. These interrelationships apply across sectors and with respect to the built form of the city. The paper aims at a long-term climate resilience of cities and their critical infrastructures, and sets out an argument for including an eco-infrastructure-based approach in strategies to address climate change. As these ecosystems have a critical role to play in building resilience and reducing vulnerabilities in cities, communities and economies at risk, the enhanced protection and management of ecosystems, biological resources and habitats can mitigate impacts and contribute to solutions as nations and cities strive to adapt to climate change.

Keywords: ecology, ecosystem, infrastructure, climate change, urban

Procedia PDF Downloads 307
3363 Modal Analysis for Optimal Location of Doubly Fed Induction-Generator-Based Wind Farms for Reduction of Small Signal Oscillation

Authors: Meet Patel, Darshan Patel, Nilay Shah

Abstract:

Excess growth of wind-based renewable energy sources is required to identify the optimal location and damping capacity of doubly fed induction-generator-based (DFIG) wind farms while it penetrates into the transmission network. In this analysis, various ratings of DFIG wind farms are penetrated into the Single Machine Infinite Bus (SMIB ) at a different distance of the transmission line. On the basis of detailed examinations, a prime position is evaluated to maximize the stability of overall systems. A damping controller is designed at an optimum location to mitigate the small oscillations. The proposed model was validated using eigenvalue analysis, calculation of the participation factor, and time-domain simulation.

Keywords: DFIG, small signal stability, eigenvalues, time domain simulation

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3362 Demonstration of Risk Factors Associated with Male Athlete Triad in Young Elite Athlete from Pakistan

Authors: Muhammad Saleem

Abstract:

Background: Inattentive food choices and engagement in excessive physical activities by male athletes can potentially lead to adverse health consequences. Objective: The aim was to ascertain the occurrence of risk factors associated with the Male Athlete Triad among young elite athletes in Pakistan. Methodology: In 2018, a cross-sectional study based on questionnaires was conducted at the Pakistan Sports Board. The study aimed to explore the risk factors related to the Male Athlete Triad in young elite athletes who were part of national training camps in major metropolitan areas. The study included proficient male elite athletes aged 18 to 25 years, capable of understanding the English questionnaire. The athletes completed a survey encompassing aspects like demographic information, educational background, Body Mass Index (BMI), sports involvement, and hours of participation. Additionally, they filled out the Eating Attitude Test-26 (EAT-26) and questionnaires assessing risks of amenorrhea and low bone mineral density. The prevalence of risk factors for each of the three components was individually evaluated. The collected data underwent analysis using SPSS-20, with descriptive statistics being applied. Results: The study comprised a sample of 90 elite athletes (mean age: 23.57 ± 2.37 years, mean BMI: 21.97 ± 1.90) engaged in various sports. The EAT-26 results indicated that 50% of athletes were at risk of developing an eating disorder. Moreover, 83.3% exhibited disordered eating behaviors that necessitated referral. Risks for amenorrhea were observed in 15% of the participants, and regarding low bone mineral density, notable risks were absent except for the consumption of caffeinated beverages, which was noted in 51.7% of participants. Conclusion: The study identified a significant prevalence of disordered eating risk among male elite athletes in Pakistan. However, the risks associated with amenorrhea and low bone mineral density were not a major concern in this particular group.

Keywords: 1. health and physical education risk factors male athlete associated with the male athlete traid in young elite athlete from pakistan., 2. sports sciences pakistan, 3. risk factors sports sciences pakistan, 4. triad and young elite athlete from pakistan

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3361 Semi-Transparent Dye-Sensitized Solar Panels for Energy Autonomous Greenhouses

Authors: A. Mourtzikou, D. Sygkridou, T. Georgakopoulos, G. Katsagounos, E. Stathatos

Abstract:

Over 60% highly transparent quasi-solid-state dye-sensitized solar cells (DSSCs) with dimension of 50x50 cm2 were fabricated via inkjet printing process using nanocomposite inks as raw materials and tested under outdoor illumination conditions. The cells were electrically characterized, and their possible application to the shell of greenhouses was also examined. The panel design was in Z-interconnection, where the working electrode was inkjet printed on one conductive glass and the counter electrode on a second glass in a sandwich configuration. Silver current collective fingers were printed on the glasses to make the internal electrical connections. In that case, the adjacent cells were connected in series via silver fingers and finally insulated using a UV curing resin to protect them from the corrosive (I-/I3-) redox couple of the electrolyte.

Keywords: Dye-sensitized solar panels, inkjet printing, quasi-solid state electrolyte, semi-transparency, scale up

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3360 Investigation of the Corrosion Inhibition Mechanism of Tagetes erecta Extract for Mild Steel in Nitric Acid: Gravimetric Studies

Authors: Selvam Noyel Victoria, Kavita Yadav, Manivannan Ramachandran

Abstract:

The extract of Tagetes erecta (marigold flower) was used as a green corrosion inhibitor for mild steel (MS) in nitric acid medium. The weight loss measurements were performed to understand the inhibition mechanism. The effect of temperature on the behaviour of mild steel corrosion without and with inhibitor was studied. The temperature studies revealed that the activation energy increased from 12 kJ/mol to 28.8 kJ/mol with the addition of 500 ppm inhibitor concentration. The thermodynamic analysis and the adsorption isotherm studies revealed that the molecules of inhibitor show physical adsorption on the surface of mild steel. Based on weight loss measurements, adsorption of the inhibitor on the surface of mild steel follows Langmuir isotherm.

Keywords: Tagetes erecta, corrosion, adsorption, inhibitor

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3359 Experimental Study on Flooding Phenomena in a Three-Phase Direct Contact Heat Exchanger for the Utilisation in Solar Pond Applications

Authors: Hameed B. Mahood, Ali Sh. Baqir, Alasdair N. Campbell

Abstract:

Experiments to study the limitation of flooding inception of three-phase direct contact condenser have been carried out in a counter-current small diameter vertical condenser. The total column height was 70 cm and 4 cm diameter. Only 48 cm has been used as an active three-phase direct contact condenser height. Vapour pentane with three different initial temperatures (40, 43.5 and 47.5 °C) and water with a constant temperature (19 °C) have been used as a dispersed phase and a continuous phase respectively. Five different continuous phase mass flow rate and four different dispersed phase mass flow rate have been tested throughout the experiments. Dimensionless correlation based on the previous common flooding correlation is proposed to calculate the up flow flooding inception of the three-phase direct contact condenser.

Keywords: Three-phase heat exchanger, condenser, solar energy, flooding phenomena

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3358 Transmission Network Expansion Planning in Deregulated Power Systems to Facilitate Competition under Uncertainties

Authors: Hooshang Mohammad Alikhani, Javad Nikoukar

Abstract:

Restructuring and deregulation of power industry have changed the objectives of transmission expansion planning and increased the uncertainties. Due to these changes, new approaches and criteria are needed for transmission planning in deregulated power systems. The objective of this research work is to present a new approach for transmission expansion planning with considering new objectives and uncertainties in deregulated power systems. The approach must take into account the desires of all stakeholders in transmission expansion planning. Market based criteria must be defined to achieve the new objectives. Combination of market based criteria, technical criteria and economical criteria must be used for measuring the goodness of expansion plans to achieve market requirements, technical requirements, and economical requirements altogether.

Keywords: deregulated power systems, transmission network, stakeholder, energy systems

Procedia PDF Downloads 654