Search results for: energy efficiency
Commenced in January 2007
Frequency: Monthly
Edition: International
Paper Count: 13267

Search results for: energy efficiency

10627 A Novel Fuzzy Second-Order Sliding Mode Control of a Doubly Fed Induction Generator for Wind Energy Conversion

Authors: Elhadj Bounadja, Mohand Oulhadj Mahmoudi, Abdelkader Djahbar, Zinelaabidine Boudjema

Abstract:

In this paper we present a novel fuzzy second-order sliding mode control (FSOSMC) for wind energy conversion system based on a doubly-fed induction generator (DFIG). The proposed control strategy combines a fuzzy logic and a second-order sliding mode for the DFIG control. This strategy presents attractive features such as chattering-free, compared to the conventional first and second order sliding mode techniques. The use of this method provides very satisfactory performance for the DFIG control. The overall strategy has been validated on a 1.5-MW wind turbine driven a DFIG using the Matlab/Simulink.

Keywords: doubly fed induction generator, fuzzy second-order sliding mode controller, wind energy

Procedia PDF Downloads 554
10626 Oil-to-Cash Reform and Inequality Evidence From Iranian Reform 2010

Authors: Mohammadali Mokhtari

Abstract:

Developing countries increasingly recognize the need to reduce energy subsidies. Cash transfers are proposed instead of subsidies to mitigate the negative effects of energy subsidy reforms. However, there is little evidence about the redistribution effect of these subsidy-to-cash reforms. We study the redistribution impact of the largest subsidy-to-cash reform in the history of developing countries in Iran in 2010. We find a strong pro-poor impact of the reform using five inequality measures, including the Gini index and the ratio of rich to poor expenditures. Finally, we show this pro-poor impact is on average and discuss other possible mechanisms by which low-income groups objected to these pro-poor reforms in the next round, which took place in November 2019 and led to wide and large protests.

Keywords: energy economics, subsidy reform, inequality, Middle East, Iran

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10625 Analysis of the Degradation of the I-V Curve of the PV Module in a Harsh Environment: Estimation of the Site-Specific Factor (Installation Area)

Authors: Maibigue Nanglet, Arafat Ousman Béchir, Mahamat Hassan Béchir

Abstract:

The economy of Central African countries is growing very fast, and the demand for energy is increasing every day. As a result, insufficient power generation is one of the major problems slowing down development. This paper explores the factors of degradation of the I-V curve of the PV Generator (GPV) in harsh environments, taking the case of two locals: Mongo and Abeche. Its objective is to quantify the voltage leaks due to the different GPV installation areas; after using the Newton-Raphson numerical method of the solar cell, a survey of several experimental measurement points was made. The results of the simulation in MATLAB/Simulink show a relative power loss factor of 11.8765% on the GPVs installed in Mongo and 8.5463% on those installed in Abeche; these results allow us to say that the supports on which the modules are installed have an average impact of 10.2114% on their efficiency.

Keywords: calculation, degradation, site, GPV, severe environment

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10624 The Relationships between Carbon Dioxide (CO2) Emissions, Energy Consumption, and GDP for Turkey: Time Series Analysis, 1980-2010

Authors: Jinhoa Lee

Abstract:

The relationships between environmental quality, energy use and economic output have created growing attention over the past decades among researchers and policy makers. Focusing on the empirical aspects of the role of CO2 emissions and energy use in affecting the economic output, this paper is an effort to fulfill the gap in a comprehensive case study at a country level using modern econometric techniques. To achieve the goal, this country-specific study examines the short-run and long-run relationships among energy consumption (using disaggregated energy sources: crude oil, coal, natural gas, electricity), carbon dioxide (CO2) emissions and gross domestic product (GDP) for Turkey using time series analysis from the year 1980-2010. To investigate the relationships between the variables, this paper employs the Phillips–Perron (PP) test for stationarity, Johansen maximum likelihood method for cointegration and a Vector Error Correction Model (VECM) for both short- and long-run causality among the research variables for the sample. All the variables in this study show very strong significant effects on GDP in the country for the long term. The long-run equilibrium in the VECM suggests negative long-run causalities from consumption of petroleum products and the direct combustion of crude oil, coal and natural gas to GDP. Conversely, positive impacts of CO2 emissions and electricity consumption on GDP are found to be significant in Turkey during the period. There exists a short-run bidirectional relationship between electricity consumption and natural gas consumption. There exists a positive unidirectional causality running from electricity consumption to natural gas consumption, while there exists a negative unidirectional causality running from natural gas consumption to electricity consumption. Moreover, GDP has a negative effect on electricity consumption in Turkey in the short run. Overall, the results support arguments that there are relationships among environmental quality, energy use and economic output but the associations can to be differed by the sources of energy in the case of Turkey over of period 1980-2010.

Keywords: CO2 emissions, energy consumption, GDP, Turkey, time series analysis

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10623 Adsoption Tests of Two Industrial Dyes by Metallic Hydroxyds

Authors: R. Berrached, H. Ait Mahamed, A. Iddou

Abstract:

Water pollution is nowadays a serious problem, due to the increasing scarcity of water and thus to the impact induced by such pollution on the human health. Various techniques are made use of to deal with water pollution. Among the most used ones, some can be enumerated: the bacterian bed, the activated mud, the Lagunage as biological processes and coagulation-floculation as a physic-chemical process. These processes are very expensive and an treatment efficiency which decreases along with the increase of the initial pollutants’ concentration. This is the reason why research has been reoriented towards the use of a process by adsorption as an alternative solution instead of the other traditional processes. In our study, we have tempted to exploit the characteristics of two metallic hydroxides Al and Fe to purify contaminated water by two industrial dyes SBL blue and SRL-150 orange. Results have shown the efficiency of the two materials on the blue SBL dye.

Keywords: Metallic Hydroxydes, industrial dyes, purification, lagunage

Procedia PDF Downloads 468
10622 Simulation and Experimentation of Solar Thermal Collector for Air Heating System Using Dynamic Ribs

Authors: Nishitha Chowdary, Prabhav Dwivedi

Abstract:

Solar radiation (or insolation) is responsible for 174 petawatts (PW) of energy reaching the Earth's atmosphere. About one-third of this is reflected in space. Solar energy is by far the most abundant source of energy on Earth. In this study to use solar energy to the fullest in a solar air heater, An analysis of a solar air heater duct roughened with fixed cylindrical ribs in 3-D has been done using CFD. These fixed cylindrical ribs have a uniform circular cross-section and are placed in transverse in-line and staggered arrangements. The orientation of ribs has been fixed and is perpendicular to the in-flow direction. Cylindrical ribs are arranged periodically with fixed pitch; therefore, one pitch length is only considered in the present study. Validation has been done with smooth as well as with roughened duct and is matched perfectly with the developed correlations. Geometric parameters, namely rib height (e), ranges from 1 to 2 mm and pitch ranges from 10 to 40 mm are used in the present investigation. Thermo-hydraulic performance parameters in terms of average Nusselt number and friction factor have been extracted for Reynolds number ranging 5000—18000 to optimize the performance of roughened duct.

Keywords: cylindrical ribs, solar air heater, thermo-hydraulic performance factor, roughened duct

Procedia PDF Downloads 159
10621 Robust Variogram Fitting Using Non-Linear Rank-Based Estimators

Authors: Hazem M. Al-Mofleh, John E. Daniels, Joseph W. McKean

Abstract:

In this paper numerous robust fitting procedures are considered in estimating spatial variograms. In spatial statistics, the conventional variogram fitting procedure (non-linear weighted least squares) suffers from the same outlier problem that has plagued this method from its inception. Even a 3-parameter model, like the variogram, can be adversely affected by a single outlier. This paper uses the Hogg-Type adaptive procedures to select an optimal score function for a rank-based estimator for these non-linear models. Numeric examples and simulation studies will demonstrate the robustness, utility, efficiency, and validity of these estimates.

Keywords: asymptotic relative efficiency, non-linear rank-based, rank estimates, variogram

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10620 Heavy Liquid Metal Coolant – the Key Safety Element in the Complex of New Nuclear Energy Technologies

Authors: A. Orlov, V. Rachkov

Abstract:

The future of Nuclear Energetics is seen in fast reactors with inherent safety working in the closed nuclear fuel cycle. The concept of inherent safety, which lies in deterministic elimination of the most severe accidents due to inherent properties of the reactor rather than through building up engineered barriers, is a cornerstone of success in ensuring safety and economic efficiency of future Nuclear Energetics. The focus of this paper is one of the key elements of inherent safety - the lead coolant of a nuclear reactor. Advantages of lead coolant for reactor application, influence on safety are reviewed. BREST-OD-300 fast reactor, currently being developed in Russia withing the “Proryv” Project utilizes lead coolant and a special set of measures and devices, called technology of lead coolant that ensures safe operation in a wide range of temperatures. Here these technological elements are reviewed, and current progress in their development is discussed.

Keywords: BREST-OD-300. , fast reactor, inherent safety, lead coolant

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10619 Heterodimetallic Ferrocenyl Dithiophosphonate Complexes of Nickel(II), Zinc(II) and Cadmium(II) as High Efficiency Co-Sensitizers in Dye-Sensitized Solar Cells

Authors: Tomilola J. Ajayi, Moses Ollengo, Lukas le Roux, Michael N. Pillay, Richard J. Staples, Shannon M. Biros Werner E. van Zyl

Abstract:

The formation, characterization, and dye-sensitized solar cell application of nickel(II), zinc(II) and cadmium(II) ferrocenyl dithiophosphonate complexes were investigated. The multidentate monoanionic ligand [S₂PFc(OH)]¯ (L1) was synthesized from the reaction between ferrocenyl Lawesson’s reagent, [FcP(=S)μ-S]₂ (FcLR), (Fc = ferrocenyl) and water. Ligand L1 could potentially coordinate to metal centers through the S, S’ and O donor atoms. The reaction between metal salt precursors and L1 produced a Ni(II) complex of the type [Ni{S₂P(Fc)(OH)}₂] (1) (molar ratio 1:2), a tetranickel (II) complex of the type [Ni₂{S₂OP(Fc)}₂]₂ (2) (molar ratio (1:1), as well as a Zn(II) complex [Zn{S₂P(Fc)(OH)}₂]₂ (3), and a Cd(II) complex [Cd{S₂P(Fc)(OH)}₂]₂ (4). Complexes 1-4 were characterized by 1H and 31P NMR and FT-IR, and complexes 1 and 2 were additionally analysed by X-Ray crystallography. After co-sensitization, the DSSCs were characterized using UV-Vis, cyclic voltammetry, electrochemical impedance spectroscopy, and photovoltaic measurements (I-V curves). Overall finding shows that co-sensitization of our compounds with ruthenium dye N719 resulted in a better overall solar conversion efficiency than only pure N719 dye under the same experimental conditions. In conclusion, we report the first examples of dye-sensitized solar cells (DSSCs) co-sensitized with ferrocenyl dithiophosphonate complexes.

Keywords: dithiophosphonate, dye sensitized solar cell, co-sensitization, solar efficiency

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10618 The Power House of Mind: Determination of Action

Authors: Sheetla Prasad

Abstract:

The focus issue of this article is to determine the mechanism of mind with geometrical analysis of human face. Research paradigm has been designed for study of spatial dynamic of face and it was found that different shapes of face have their own function for determine the action of mind. The functional ratio (FR) of face has determined the behaviour operation of human beings. It is not based on the formulistic approach of prediction but scientific dogmatism and mathematical analysis is the root of the prediction of behaviour. For analysis, formulae were developed and standardized. It was found that human psyche is designed in three forms; manipulated, manifested and real psyche. Functional output of the psyche has been determined by degree of energy flow in the psyche and reserve energy for future. Face is the recipient and transmitter of energy but distribution and control is the possible by mind. Mind directs behaviour. FR indicates that the face is a power house of energy and as per its geometrical domain force of behaviours has been designed and actions are possible in the nature of individual. The impact factor of this study is the promotion of human capital for job fitness objective and minimization of criminalization in society.

Keywords: functional ratio, manipulated psyche, manifested psyche, real psyche

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10617 Machine Learning Approaches Based on Recency, Frequency, Monetary (RFM) and K-Means for Predicting Electrical Failures and Voltage Reliability in Smart Cities

Authors: Panaya Sudta, Wanchalerm Patanacharoenwong, Prachya Bumrungkun

Abstract:

As With the evolution of smart grids, ensuring the reliability and efficiency of electrical systems in smart cities has become crucial. This paper proposes a distinct approach that combines advanced machine learning techniques to accurately predict electrical failures and address voltage reliability issues. This approach aims to improve the accuracy and efficiency of reliability evaluations in smart cities. The aim of this research is to develop a comprehensive predictive model that accurately predicts electrical failures and voltage reliability in smart cities. This model integrates RFM analysis, K-means clustering, and LSTM networks to achieve this objective. The research utilizes RFM analysis, traditionally used in customer value assessment, to categorize and analyze electrical components based on their failure recency, frequency, and monetary impact. K-means clustering is employed to segment electrical components into distinct groups with similar characteristics and failure patterns. LSTM networks are used to capture the temporal dependencies and patterns in customer data. This integration of RFM, K-means, and LSTM results in a robust predictive tool for electrical failures and voltage reliability. The proposed model has been tested and validated on diverse electrical utility datasets. The results show a significant improvement in prediction accuracy and reliability compared to traditional methods, achieving an accuracy of 92.78% and an F1-score of 0.83. This research contributes to the proactive maintenance and optimization of electrical infrastructures in smart cities. It also enhances overall energy management and sustainability. The integration of advanced machine learning techniques in the predictive model demonstrates the potential for transforming the landscape of electrical system management within smart cities. The research utilizes diverse electrical utility datasets to develop and validate the predictive model. RFM analysis, K-means clustering, and LSTM networks are applied to these datasets to analyze and predict electrical failures and voltage reliability. The research addresses the question of how accurately electrical failures and voltage reliability can be predicted in smart cities. It also investigates the effectiveness of integrating RFM analysis, K-means clustering, and LSTM networks in achieving this goal. The proposed approach presents a distinct, efficient, and effective solution for predicting and mitigating electrical failures and voltage issues in smart cities. It significantly improves prediction accuracy and reliability compared to traditional methods. This advancement contributes to the proactive maintenance and optimization of electrical infrastructures, overall energy management, and sustainability in smart cities.

Keywords: electrical state prediction, smart grids, data-driven method, long short-term memory, RFM, k-means, machine learning

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10616 Strategies for Tackling Climate Change: Review of Sustainability and Air-Conditioning

Authors: Tosin T. Oye, Keng Goh, Naren Gupta, Toyosi K. Oye

Abstract:

One of the most extreme difficulties confronting humankind in the twenty-first century is the consumption of energy. Non-renewable energy sources have been the fundamental energy assets for human culture. The consumption of energy sources emanating from the use of air-conditioning is still causing and has caused harm to the environment and human health. The request for energy could be double or perhaps triple in the future because of the utilization of air-conditioning systems as the worldwide population develops and emerging districts grow their economics. This has recently raised worries in sustainable development over climate change, global warming, ozone layer reduction, health issues, and possible supply problems. As a result of the improvement of way of life, air-conditioning has generally been applied. Nevertheless, environmental pollutions and health issues related with the use of air-conditioning unfolds more as often as possible. In order to diminish their level of undesirable impact on the environment, it is essential to establish suitable strategies for tackling climate change. Therefore, this paper aims to review and analyze studies in sustainability and air- conditioning and subsequently suggest strategies for combatting climate change. Future perspectives for tackling climate change are likewise suggested. The key findings revealed that it is required to establish sustainability measures to reduce the level of energy consumption and carbon emissions in a bid to effectively tackle climate change and its impact on the environment, and then raise public alertness towards the adverse impact of climate change arising from the use of air-conditioning systems. The research outcome offers valuable awareness to the general public, organizations, policymakers, and the government in making future municipal zones sustainable and more climate resilient.

Keywords: air-conditioning, climate change, environment, human health, sustainability

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10615 Temperature Susceptibility for Optimal Biogas Production

Authors: Ujjal Chattaraj, Pbharat Saikumar, Thinley Dorji

Abstract:

Earth is going to be a planet where no further life can sustain if people continue to pollute the environment. We need energy and fuels everyday for heating and lighting purposes in our life. It’s high time we know this problem and take measures at-least to reduce pollution and take alternative measures for everyday livelihood. Biogas is one of them. It is very essential to define and control the parameters for optimization of biogas production. Biogas plants can be made of different size, but it is very vital to make a biogas which will be cost effective, with greater efficiency (more production) and biogas plants that will sustain for a longer period of time for usage. In this research, experiments were carried out only on cow dung and Chicken manure depending on the substrates people out there (Bhutan) used. The experiment was done within 25 days and was tested for different temperatures and found out which produce more amount. Moreover, it was also statistically tested for their dependency and non-dependency which gave clear idea more on their production.

Keywords: digester, mesophilic temperature, organic manure, statistical analysis, thermophilic temperature, t-test

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10614 Effect of PMMA Shield on the Patient Dose Equivalent from Photoneutrons Produced by High Energy Medical Linacs

Authors: Seyed Mehdi Hashemi, Gholamreza Raisali, Mehran Taheri

Abstract:

One of the important problems of using high energy linacs at IMRT is the production of photoneutrons. Besides the clinically useful photon beams, high-energy photon beams from medical linacs produce secondary neutrons. These photoneutrons increase the patient dose and may cause secondary malignancies. The effect of the shield on the reduction of photoneutron dose equivalent produced by a high energy medical linac at the patient plane is investigated in this study. To determine the photoneutron dose equivalent received to the patient a Varian linac working at 18 MV photon mode investigated. Photoneutron dose equivalent measured with Polycarbonate films of 0.25 mm thick. PC films placed at distances of 0, 10, 20, and 50 cm from the center of X-ray field on the patient couch. The results show that by increasing the distance from the center of the X-ray beam towards the periphery, the photoneutron dose equivalent decreases rapidly for both open and shielded fields and that by inserting the shield in the path of the X-ray beam, the photoneutron dose equivalent was decreased obviously compared to open field. Results show the shield, significantly reduces photoneutron dose equivalent to the patient. Results can be readily generalized to other models of medical linacs. It may be concluded that using this kind of shield can help more safe, inexpensive and efficient employment of high energy linacs in radiotherapy and IMRT.

Keywords: photoneutron, Linac, PMMA shield, equivalent dose

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10613 Scenarios for the Energy Transition in Residential Buildings for the European Regions

Authors: Domenico Carmelo Mongelli, Laura Carnieletto, Michele De Carli, Filippo Busato

Abstract:

Starting from the current context in which the Russian invasion in Ukraine has highlighted Europe's dependence on natural gas imports for heating buildings, this study proposes solutions to resolve this dependency and evaluates related scenarios in the near future. In the first part of this work the methodologies and results of the economic impact are indicated by simulating a massive replacement of boilers powered by fossil fuels with electrically powered hightemperature air-water heat pumps for heating residential buildings in different European climates, without changing the current energy mix. For each individual European region, the costs for the purchase and installation of heat pumps for all residential buildings have been determined. Again for each individual European region, the economic savings during the operation phase that would be obtained in this future scenario of energy transition from fossil fuels to the electrification of domestic heating were calculated. For the European regions for which the economic savings were identified as positive, the payback times of the economic investments were analysed. In the second part of the work, hypothesizing different scenarios for a possible greater use of renewable energy sources and therefore with different possible future scenarios of the energy mix, the methodologies and results of the simulations on the economic analysis and on the environmental analysis are reported which have allowed us to evaluate the future effects of the energy transition from boilers to heat pumps for each European region. In the third part, assuming a rapid short-term diffusion of cooling for European residential buildings, the penetration shares in the cooling market and future projections of energy needs for cooling for each European region have been identified. A database was created where the results of this research relating to 38 European Nations divided into 179 regions were reported. Other previous works on the topics covered were limited to analyzing individual European nations, without ever going into detail about the individual regions within each nation, while the original contribution of the present work lies in the fact that the results achieved allow a specific numerical analysis and punctual for every single European region.

Keywords: buildings, energy, Europe, future

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10612 Comparison of Hydrogen and Electrification Perspectives in Decarbonizing the Transport Sector

Authors: Matteo Nicoli, Gianvito Colucci, Valeria Di Cosmo, Daniele Lerede, Laura Savoldi

Abstract:

The transport sector is currently responsible for approximately 1/3 of greenhouse gas emissions in Europe. In the wider context of achieving carbon neutrality of the global energy system, different alternatives are available to decarbonizethe transport sector. In particular, while electricity is already the most consumed energy commodity in rail transport, battery electric vehicles are one of the zero-emissions options on the market for road transportation. On the other hand, hydrogen-based fuel cell vehicles are available for road and non-road vehicles. The European Commission is strongly pushing toward the integration of hydrogen in the energy systems of European countries and its widespread adoption as an energy vector to achieve the Green Deal targets. Furthermore, the Italian government is defining hydrogen-related objectives with the publication of a dedicated Hydrogen Strategy. The adoption of energy system optimization models to study the possible penetration of alternative zero-emitting transport technologies gives the opportunity to perform an overall analysis of the effects that the development of innovative technologies has on the entire energy system and on the supply-side, devoted to the production of energy carriers such as hydrogen and electricity. Using an open-source modeling framework such as TEMOA, this work aims to compare the role of hydrogen and electric vehicles in the decarbonization of the transport sector. The analysis investigates the advantages and disadvantages of adopting the two options, from the economic point of view (costs associated with the two options) and the environmental one (looking at the emissions reduction perspectives). Moreover, an analysis on the profitability of the investments in hydrogen and electric vehicles will be performed. The study investigates the evolution of energy consumption and greenhouse gas emissions in different transportation modes (road, rail, navigation, and aviation) by detailed analysis of the full range of vehicles included in the techno-economic database used in the TEMOA model instance adopted for this work. The transparency of the analysis is guaranteed by the accessibility of the TEMOA models, based on an open-access source code and databases.

Keywords: battery electric vehicles, decarbonization, energy system optimization models, fuel cell vehicles, hydrogen, open-source modeling, TEMOA, transport

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10611 Study on Capability of the Octocopter Configuration in Finite Element Analysis Simulation Environment

Authors: Benil Mathew Baby, Leonid Shpanin, Misko Abramiuk

Abstract:

High-voltage energy production on board the unmanned aerial vehicle (UAV) is one of the most rapidly growing emerging technologies for different applications in aerospace. Different energy harvesting and production techniques have already been investigated in multirotor drones, where the energy collected comes from the systems surrounding the ambient environment and typically involves the conversion of solar, kinetic, or thermal energies into electrical energy. In this contribution, a UAV structure is proposed for the production of a few tens of kilovolts on board of the UAV. The high voltage production mechanism on board of the UAV has not been investigated previously. The UAV geometry using the multirotor drone for production the high voltage on board of the UAV has been investigated theoretically using the ANSYS and MATLAB Finite Element Analysis (FEA) simulation tools. The industrially made MANTIS X8-PRO octocopter frame kit was used to explore the octocopter operation which was modelled for simulation studies. The high voltage electric circuit and components using octocopter geometry are developed through the integration of the mechanical parts on board of the UAV. Analysis of the modelled octocopter geometry and its performance is presented via a graphical representation of simulated parameters. The possibility of not using the landing gear in the proposed octocopter geometry is demonstrated. The conducted study evaluates the octocopter’s high voltage control technique and its impact on UAV energy consumption. FEA simulation results of the modelled high voltage electric circuit on board of the octocopter are presented exploring the performance of the octocopter and the structural challenges of its configuration. Applications of the proposed octocopter structure are discussed.

Keywords: high voltage production, energy harvesting, object modeling and control, unmanned aerial vehicle

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10610 Switchable Lipids: From a Molecular Switch to a pH-Sensitive System for the Drug and Gene Delivery

Authors: Jeanne Leblond, Warren Viricel, Amira Mbarek

Abstract:

Although several products have reached the market, gene therapeutics are still in their first stages and require optimization. It is possible to improve their lacking efficiency by the use of carefully engineered vectors, able to carry the genetic material through each of the biological barriers they need to cross. In particular, getting inside the cell is a major challenge, because these hydrophilic nucleic acids have to cross the lipid-rich plasmatic and/or endosomal membrane, before being degraded into lysosomes. It takes less than one hour for newly endocytosed liposomes to reach highly acidic lysosomes, meaning that the degradation of the carried gene occurs rapidly, thus limiting the transfection efficiency. We propose to use a new pH-sensitive lipid able to change its conformation upon protonation at endosomal pH values, leading to the disruption of the lipidic bilayer and thus to the fast release of the nucleic acids into the cytosol. It is expected that this new pH-sensitive mechanism promote endosomal escape of the gene, thereby its transfection efficiency. The main challenge of this work was to design a preparation presenting fast-responding lipidic bilayer destabilization properties at endosomal pH 5 while remaining stable at blood pH value and during storage. A series of pH-sensitive lipids able to perform a conformational switch upon acidification were designed and synthesized. Liposomes containing these switchable lipids, as well as co-lipids were prepared and characterized. The liposomes were stable at 4°C and pH 7.4 for several months. Incubation with siRNA led to the full entrapment of nucleic acids as soon as the positive/negative charge ratio was superior to 2. The best liposomal formulation demonstrated a silencing efficiency up to 10% on HeLa cells, very similar to a commercial agent, with a lowest toxicity than the commercial agent. Using flow cytometry and microscopy assays, we demonstrated that drop of pH was required for the transfection efficiency, since bafilomycin blocked the transfection efficiency. Additional evidence was brought by the synthesis of a negative control lipid, which was unable to switch its conformation, and consequently exhibited no transfection ability. Mechanistic studies revealed that the uptake was mediated through endocytosis, by clathrin and caveolae pathways, as reported for previous lipid nanoparticle systems. This potent system was used for the treatment of hypercholesterolemia. The switchable lipids were able to knockdown PCSK9 expression on human hepatocytes (Huh-7). Its efficiency is currently evaluated on in vivo mice model of PCSK9 KO mice. In summary, we designed and optimized a new cationic pH-sensitive lipid for gene delivery. Its transfection efficiency is similar to the best available commercial agent, without the usually associated toxicity. The promising results lead to its use for the treatment of hypercholesterolemia on a mice model. Anticancer applications and pulmonary chronic disease are also currently investigated.

Keywords: liposomes, siRNA, pH-sensitive, molecular switch

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10609 The Analysis of Application of Green Bonds in New Energy Vehicles in China: From Evolutionary Game Theory

Authors: Jing Zhang

Abstract:

Sustainable development in the new energy vehicles field is the requirement of the net zero aim. Green bonds are accepted as a practical financial tool to boost the transformation of relevant enterprises. The paper analyzes the interactions among governments, enterprises of new energy vehicles, and financial institutions by an evolutionary game theory model and offers advice to stakeholders in China. The decision-making subjects of green behavior are affected by experiences, interests, perception ability, and risk preference, so it is difficult for them to be completely rational. Based on the bounded rationality hypothesis, this paper applies prospect theory in the evolutionary game analysis framework and analyses the costs of government regulation of enterprises adopting green bonds. The influence of the perceived value of revenue prospect and the probability and risk transfer coefficient of the government's active regulation on the decision-making agent's strategy is verified by numerical simulation. Finally, according to the research conclusions, policy suggestions are given to promote green bonds.

Keywords: green bonds, new energy vehicles, sustainable development, evolutionary Game Theory model

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10608 Comparison of Machine Learning Models for the Prediction of System Marginal Price of Greek Energy Market

Authors: Ioannis P. Panapakidis, Marios N. Moschakis

Abstract:

The Greek Energy Market is structured as a mandatory pool where the producers make their bid offers in day-ahead basis. The System Operator solves an optimization routine aiming at the minimization of the cost of produced electricity. The solution of the optimization problem leads to the calculation of the System Marginal Price (SMP). Accurate forecasts of the SMP can lead to increased profits and more efficient portfolio management from the producer`s perspective. Aim of this study is to provide a comparative analysis of various machine learning models such as artificial neural networks and neuro-fuzzy models for the prediction of the SMP of the Greek market. Machine learning algorithms are favored in predictions problems since they can capture and simulate the volatilities of complex time series.

Keywords: deregulated energy market, forecasting, machine learning, system marginal price

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10607 Guided Energy Theory of a Particle: Answered Questions Arise from Quantum Foundation

Authors: Desmond Agbolade Ademola

Abstract:

This work aimed to introduce a theory, called Guided Energy Theory of a particle that answered questions that arise from quantum foundation, quantum mechanics theory, and interpretation such as: what is nature of wavefunction? Is mathematical formalism of wavefunction correct? Does wavefunction collapse during measurement? Do quantum physical entanglement and many world interpretations really exist? In addition, is there uncertainty in the physical reality of our nature as being concluded in the Quantum theory? We have been able to show by the fundamental analysis presented in this work that the way quantum mechanics theory, and interpretation describes nature is not correlated with physical reality. Because, we discovered amongst others that, (1) Guided energy theory of a particle fundamentally provides complete physical observable series of quantized measurement of a particle momentum, force, energy e.t.c. in a given distance and time.In contrast, quantum mechanics wavefunction describes that nature has inherited probabilistic and indeterministic physical quantities, resulting in unobservable physical quantities that lead to many worldinterpretation.(2) Guided energy theory of a particle fundamentally predicts that it is mathematically possible to determine precise quantized measurementof position and momentum of a particle simultaneously. Because, there is no uncertainty in nature; nature however naturally guides itself against uncertainty. Contrary to the conclusion in quantum mechanics theory that, it is mathematically impossible to determine the position and the momentum of a particle simultaneously. Furthermore, we have been able to show by this theory that, it is mathematically possible to determine quantized measurement of force acting on a particle simultaneously, which is not possible on the premise of quantum mechanics theory. (3) It is evidently shown by our theory that, guided energy does not collapse, only describes the lopsided nature of a particle behavior in motion. This pretty offers us insight on gradual process of engagement - convergence and disengagement – divergence of guided energy holders which further highlight the picture how wave – like behavior return to particle-like behavior and how particle – like behavior return to wave – like behavior respectively. This further proves that the particles’ behavior in motion is oscillatory in nature. The mathematical formalism of Guided energy theory shows that nature is certainty whereas the mathematical formalism of Quantum mechanics theory shows that nature is absolutely probabilistics. In addition, the nature of wavefunction is the guided energy of the wave. In conclusion, the fundamental mathematical formalism of Quantum mechanics theory is wrong.

Keywords: momentum, physical entanglement, wavefunction, uncertainty

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10606 Comparison Between Fuzzy and P&O Control for MPPT for Photovoltaic System Using Boost Converter

Authors: M. Doumi, A. Miloudi, A. G. Aissaoui, K. Tahir, C. Belfedal, S. Tahir

Abstract:

The studies on the photovoltaic system are extensively increasing because of a large, secure, essentially exhaustible and broadly available resource as a future energy supply. However, the output power induced in the photovoltaic modules is influenced by an intensity of solar cell radiation, temperature of the solar cells and so on. Therefore, to maximize the efficiency of the photovoltaic system, it is necessary to track the maximum power point of the PV array, for this Maximum Power Point Tracking (MPPT) technique is used. Some MPPT techniques are available in that perturbation and observation (P&O) and Fuzzy logic controller (FLC). The fuzzy control method has been compared with perturb and observe (P&O) method as one of the most widely conventional method used in this area. Both techniques have been analyzed and simulated. MPPT using fuzzy logic shows superior performance and more reliable control with respect to the P&O technique for this application.

Keywords: photovoltaic system, MPPT, perturb and observe, fuzzy logic

Procedia PDF Downloads 609
10605 Probing Extensive Air Shower Primaries and Their Interactions by Combining Individual Muon Tracks and Shower Depth

Authors: Moon Moon Devi, Ran Budnik

Abstract:

The current large area cosmic ray detector surface arrays typically measure only the net flux and arrival-time of the charged particles produced in an extensive air shower (EAS). Measurement of the individual charged particles at a surface array will provide additional distinguishing parameters to identify the primary and to map the very high energy interactions in the upper layers of the atmosphere. In turn, these may probe anomalies in QCD interactions at energies beyond the reach of current accelerators. The recent attempts of studying the individual muon tracks are limited in their expandability to larger arrays and can only probe primary particles with energy up to about 10^15.5 eV. New developments in detector technology allow for a realistic cost of large area detectors, however with limitations on energy resolutions, directional information, and dynamic range. In this study, we perform a simulation study using CORSIKA to combine the energy spectrum and lateral spread of the muons with the longitudinal depth (Xmax) of an EAS initiated by a primary at ultra high energies (10¹⁶ – 10¹⁹) eV. Using proton and iron as the shower primaries, we show that the muon observables and Xmax together can be used to distinguish the primary. This study can be used to design a future detector for the surface array, which will be able to enhance our knowledge of primaries and QCD interactions.

Keywords: ultra high energy extensive air shower, muon tracking, air shower primaries, QCD interactions

Procedia PDF Downloads 231
10604 The Lexicographic Serial Rule

Authors: Thi Thao Nguyen, Andrew McLennan, Shino Takayama

Abstract:

We study the probabilistic allocation of finitely many indivisible objects to finitely many agents. Well known allocation rules for this problem include random priority, the market mechanism proposed by Hylland and Zeckhauser [1979], and the probabilistic serial rule of Bogomolnaia and Moulin [2001]. We propose a new allocation rule, which we call the lexico-graphic (serial) rule, that is tailored for situations in which each agent's primary concern is to maximize the probability of receiving her favourite object. Three axioms, lex efficiency, lex envy freeness and fairness, are proposed and fully characterize the lexicographic serial rule. We also discuss how our axioms and the lexicographic rule are related to other allocation rules, particularly the probabilistic serial rule.

Keywords: Efficiency, Envy free, Lexicographic, Probabilistic Serial Rule

Procedia PDF Downloads 154
10603 Performance of a Solar Heating System on the Microclimate of an Agricultural Greenhouse

Authors: Nora Arbaoui, Rachid Tadili, Ilham Ihoume

Abstract:

Climate change and its effects on low external temperatures in winter require great consumption of energy to improve the greenhouse microclimate and increase agricultural production. To reduce the amount of energy consumed, a solar system has been developed to heat an agricultural greenhouse. This system is based on a transfer fluid that will circulate inside the greenhouse through a solar copper coil positioned on the roof of the greenhouse. This thermal energy accumulated during the day will be stored to be released during the night to improve the greenhouse’s microclimate. The use of this solar heating system has resulted in an average increase in the greenhouse’s indoor temperature of 8.3°C compared to the outdoor environment. This improved temperature has created a more favorable climate for crops and has subsequently had a positive effect on their development, quality, and production.

Keywords: solar system, agricultural greenhouse, heating, cooling, storage, drying

Procedia PDF Downloads 95
10602 Statistical Analysis and Optimization of a Process for CO2 Capture

Authors: Muftah H. El-Naas, Ameera F. Mohammad, Mabruk I. Suleiman, Mohamed Al Musharfy, Ali H. Al-Marzouqi

Abstract:

CO2 capture and storage technologies play a significant role in contributing to the control of climate change through the reduction of carbon dioxide emissions into the atmosphere. The present study evaluates and optimizes CO2 capture through a process, where carbon dioxide is passed into pH adjusted high salinity water and reacted with sodium chloride to form a precipitate of sodium bicarbonate. This process is based on a modified Solvay process with higher CO2 capture efficiency, higher sodium removal, and higher pH level without the use of ammonia. The process was tested in a bubble column semi-batch reactor and was optimized using response surface methodology (RSM). CO2 capture efficiency and sodium removal were optimized in terms of major operating parameters based on four levels and variables in Central Composite Design (CCD). The operating parameters were gas flow rate (0.5–1.5 L/min), reactor temperature (10 to 50 oC), buffer concentration (0.2-2.6%) and water salinity (25-197 g NaCl/L). The experimental data were fitted to a second-order polynomial using multiple regression and analyzed using analysis of variance (ANOVA). The optimum values of the selected variables were obtained using response optimizer. The optimum conditions were tested experimentally using desalination reject brine with salinity ranging from 65,000 to 75,000 mg/L. The CO2 capture efficiency in 180 min was 99% and the maximum sodium removal was 35%. The experimental and predicted values were within 95% confidence interval, which demonstrates that the developed model can successfully predict the capture efficiency and sodium removal using the modified Solvay method.

Keywords: CO2 capture, water desalination, Response Surface Methodology, bubble column reactor

Procedia PDF Downloads 294
10601 Measures of Corporate Governance Efficiency on the Quality Level of Value Relevance Using IFRS and Corporate Governance Acts: Evidence from African Stock Exchanges

Authors: Tchapo Tchaga Sophia, Cai Chun

Abstract:

This study measures the efficiency level of corporate governance to improve the quality level of value relevance in the resolution of market value efficiency increase issues, transparency problems, risk frauds, agency problems, investors' confidence, and decision-making issues using IFRS and Corporate Governance Acts (CGA). The final sample of this study contains 3660 firms from ten countries' stock markets from 2010 to 2020. Based on the efficiency market theory and the positive accounting theory, this paper uses multiple econometrical methods (DID method, multivariate and univariate regression methods) and models (Ohlson model and compliance index model) regression to see the incidence results of corporate governance mechanisms on the value relevance level under the influence of IFRS and corporate governance regulations act framework in Africa's stock exchanges for non-financial firms. The results on value relevance show that the corporate governance system, strengthened by the adoption of IFRS and enforcement of new corporate governance regulations, produces better financial statement information when its compliance level is high. And that is both value-relevant and comparable to results in more developed markets. Similar positive and significant results were obtained when predicting future book value per share and earnings per share through the determination of stock price and stock return. The findings of this study have important implications for regulators, academics, investors, and other users regarding the effects of IFRS and the Corporate Governance Act (CGA) on the relationship between corporate governance and accounting information relevance in the African stock market. The contributions of this paper are also based on the uniqueness of the data used in this study. The unique data is from Africa, and not all existing findings provide evidence for Africa and of the DID method used to examine the relationship between corporate governance and value relevance on African stock exchanges.

Keywords: corporate governance value, market efficiency value, value relevance, African stock market, stock return-stock price

Procedia PDF Downloads 62
10600 Ge₁₋ₓSnₓ Alloys with Tuneable Energy Band Gap on GaAs (100) Substrate Manufactured by a Modified Magnetron Co-Sputtering

Authors: Li Qian, Jinchao Tong, Daohua Zhang, Weijun Fan, Fei Suo

Abstract:

Photonic applications based on group IV semiconductors have always been an interest but also a challenge for the research community. We report manufacturing group IV Ge₁₋ₓSnₓ alloys with tuneable energy band gap on (100) GaAs substrate by a modified radio frequency magnetron co-sputtering. Images were taken by atomic force microscope, and scanning electron microscope clearly demonstrates a smooth surface profile, and Ge₁₋ₓSnₓ nano clusters are with the size of several tens of nanometers. Transmittance spectra were measured by Fourier Transform Infrared Spectroscopy that showed changing energy gaps with the variation in elementary composition. Calculation results by 8-band k.p method are consistent with measured gaps. Our deposition system realized direct growth of Ge₁₋ₓSnₓ thin film on GaAs (100) substrate by sputtering. This simple deposition method was modified to be able to grow high-quality photonic materials with tuneable energy gaps. This work provides an alternative and successful method for fabricating Group IV photonic semiconductor materials.

Keywords: GeSn, crystal growth, sputtering, photonic

Procedia PDF Downloads 150
10599 System Transformation: Transitioning towards Low Carbon, Resource Efficient, and Circular Economy for Global Sustainability

Authors: Anthony Halog

Abstract:

In the coming decades the world that we know today will be drastically transformed. Population and economic growth, particularly in developing countries, are radically changing the demand for food and natural resources. Due to the transformations caused by these megatrends, especially economic growth which is rapidly expanding the middle class and changing consumption patterns worldwide, it is expected that this will result to an increase of approximately 40 percent in the demand for food, water, energy and other resources in the next decades. To fulfill this demand in a sustainable and efficient manner while avoiding food and water scarcity as well as environmental catastrophes in the near future, some industries, particularly the ones involved in food and energy production, have to drastically change its current production systems towards circular and green economy. In Australia, the agri-food industry has played a very important role in the scenario described above. It is one of the major food exporters in the world, supplying fast growing international markets in Asia and the Middle East. Though the Australian food supply chains are economically and technologically developed, it has been facing enduring challenges about its international competitiveness and environmental burdens caused by its production processes. An integrated framework for sustainability assessment is needed to precisely identify inefficiencies and environmental impacts created during food production processes. This research proposes a combination of industrial ecology and systems science based methods and tools intending to develop a novel and useful methodological framework for life cycle sustainability analysis of the agri-food industry. The presentation highlights circular economy paradigm aiming to implement sustainable industrial processes to transform the current industrial model of agri-food supply chains. The results are expected to support government policy makers, business decision makers and other stakeholders involved in agri-food-energy production system in pursuit of green and circular economy. The framework will assist future life cycle and integrated sustainability analysis and eco-redesign of food and other industrial systems.

Keywords: circular economy, eco-efficiency, agri-food systems, green economy, life cycle sustainability assessment

Procedia PDF Downloads 285
10598 Assessment of Solar Hydrogen Production in Energetic Hybrid PV-PEMFC System

Authors: H. Rezzouk, M. Hatti, H. Rahmani, S. Atoui

Abstract:

This paper discusses the design and analysis of a hybrid PV-Fuel cell energy system destined to power a DC load. The system is composed of a photovoltaic array, a fuel cell, an electrolyzer and a hydrogen tank. HOMER software is used in this study to calculate the optimum capacities of the power system components that their combination allows an efficient use of solar resource to cover the hourly load needs. The optimal system sizing allows establishing the right balance between the daily electrical energy produced by the power system and the daily electrical energy consumed by the DC load using a 28 KW PV array, a 7.5 KW fuel cell, a 40KW electrolyzer and a 270 Kg hydrogen tank. The variation of powers involved into the DC bus of the hybrid PV-fuel cell system has been computed and analyzed for each hour over one year: the output powers of the PV array and the fuel cell, the input power of the elctrolyzer system and the DC primary load. Equally, the annual variation of stored hydrogen produced by the electrolyzer has been assessed. The PV array contributes in the power system with 82% whereas the fuel cell produces 18%. 38% of the total energy consumption belongs to the DC primary load while the rest goes to the electrolyzer.

Keywords: electrolyzer, hydrogen, hydrogen fueled cell, photovoltaic

Procedia PDF Downloads 495