Search results for: uniform excess energy theory
13368 Study of the Energy Levels in the Structure of the Laser Diode GaInP
Authors: Abdelali Laid, Abid Hamza, Zeroukhi Houari, Sayah Naimi
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This work relates to the study of the energy levels and the optimization of the Parameter intrinsic (a number of wells and their widths, width of barrier of potential, index of refraction etc.) and extrinsic (temperature, pressure) in the Structure laser diode containing the structure GaInP. The methods of calculation used; - method of the empirical pseudo potential to determine the electronic structures of bands, - graphic method for optimization. The found results are in concord with those of the experiment and the theory.Keywords: semi-conductor, GaInP/AlGaInP, pseudopotential, energy, alliages
Procedia PDF Downloads 48313367 Thermomagnetic Convection of a Ferrofluid in a Non-Uniform Magnetic Field Induced a Current Carrying Wire
Authors: Ashkan Vatani, Peter Woodfield, Nam-Trung Nguyen, Dzung Dao
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Thermomagnetic convection of a ferrofluid flow induced by the non-uniform magnetic field around a current-carrying wire was theoretically analyzed and experimentally tested. To show this phenomenon, the temperature rise of a hot wire, immersed in DIW and Ferrofluid, as a result of joule heating has been measured using a transient hot-wire technique. When current is applied to the wire, a temperature gradient is imposed on the magnetic fluid resulting in non-uniform magnetic susceptibility of the ferrofluid that results in a non-uniform magnetic body force which makes the ferrofluid flow as a bulk suspension. For the case of the wire immersed in DIW, free convection is the only means of cooling, while for the case of ferrofluid a combination of both free convection and thermomagnetic convection is expected to enhance the heat transfer from the wire beyond that of DIW. Experimental results at different temperatures and for a range of constant currents applied to the wire show that thermomagnetic convection becomes effective for the currents higher than 1.5A at all temperatures. It is observed that the onset of thermomagnetic convection is directly proportional to the current applied to the wire and that the thermomagnetic convection happens much faster than the free convection. Calculations show that a 35% enhancement in heat transfer can be expected for the ferrofluid compared to DIW, for a 3A current applied to the wire.Keywords: cooling, ferrofluid, thermomagnetic convection, magnetic field
Procedia PDF Downloads 25813366 Thermodynamic Behaviour of Binary Mixtures of 1, 2-Dichloroethane with Some Cyclic Ethers: Experimental Results and Modelling
Authors: Fouzia Amireche-Ziar, Ilham Mokbel, Jacques Jose
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The vapour pressures of the three binary mixtures: 1, 2- dichloroethane + 1,3-dioxolane, + 1,4-dioxane or + tetrahydropyrane, are carried out at ten temperatures ranging from 273 to 353.15 K. An accurate static device was employed for these measurements. The VLE data were reduced using the Redlich-Kister equation by taking into consideration the vapour pressure non-ideality in terms of the second molar virial coefficient. The experimental data were compared to the results predicted with the DISQUAC and Dortmund UNIFAC group contribution models for the total pressures P and the excess molar Gibbs energies GE.Keywords: disquac model, dortmund UNIFAC model, excess molar Gibbs energies GE, VLE
Procedia PDF Downloads 25513365 Internal and External Influences on the Firm Objective
Authors: A. Briseno, A, Zorrilla
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Firms are increasingly responding to social and environmental claims from society. Practices oriented to attend issues such as poverty, work equality, or renewable energy, are being implemented more frequently by firms to address impacts on sustainability. However, questions remain on how the responses of firms vary across industries and regions between the social and the economic objectives. Using concepts from organizational theory and social network theory, this paper aims to create a theoretical framework that explains the internal and external influences that make a firm establish its objective. The framework explains why firms might have a different objective orientation in terms of its economic and social prioritization.Keywords: organizational identity, social network theory, firm objective, value maximization, social responsibility
Procedia PDF Downloads 30313364 On the Catalytic Combustion Behaviors of CH4 in a MCFC Power Generation System
Authors: Man Young Kim
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Catalytic combustion is generally accepted as an environmentally preferred alternative for the generation of heat and power from fossil fuels mainly due to its advantages related to the stable combustion under very lean conditions with low emissions of NOx, CO, and UHC at temperatures lower than those occurred in conventional flame combustion. Despite these advantages, the commercial application of catalytic combustion has been delayed because of complicated reaction processes and the difficulty in developing appropriate catalysts with the required stability and durability. To develop the catalytic combustors, detailed studies on the combustion characteristics of catalytic combustion should be conducted. To the end, in current research, quantitative studies on the combustion characteristics of the catalytic combustors, with a Pd-based catalyst for MCFC power generation systems, relying on numerical simulations have been conducted. In addition, data from experimental studies of variations in outlet temperatures and fuel conversion, taken after operating conditions have been used to validate the present numerical approach. After introducing the governing equations for mass, momentum, and energy equations as well as a description of catalytic combustion kinetics, the effects of the excess air ratio, space velocity, and inlet gas temperature on the catalytic combustion characteristics are extensively investigated. Quantitative comparisons are also conducted with previous experimental data. Finally, some concluding remarks are presented.Keywords: catalytic combustion, methane, BOP, MCFC power generation system, inlet temperature, excess air ratio, space velocity
Procedia PDF Downloads 26913363 Choosing the Green Energy Option: A Willingness to Pay Study of Metro Manila Residents for Solar Renewable Energy
Authors: Paolo Magnata
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The energy market in the Philippines remains to have one of the highest electricity rates in the region averaging at US$0.16/kWh (PHP6.89/kWh), excluding VAT, as opposed to the overall energy market average of US$0.13/kWh. The movement towards renewable energy, specifically solar energy, will pose as an expensive one with the country’s energy sector providing Feed-in-Tariff rates as high as US$0.17/kWh (PHP8.69/kWh) for solar energy power plants. Increasing the share of renewables at the current state of the energy regulatory background would yield a three-fold increase in residential electricity bills. The issue lies in the uniform charge that consumers bear regardless of where the electricity is sourced resulting in rates that only consider costs and not the consumers. But if they are given the option to choose where their electricity comes from, a number of consumers may potentially choose economically costlier sources of electricity due to higher levels of utility coupled with the willingness to pay of consuming environmentally-friendly sourced electricity. A contingent valuation survey was conducted to determine their willingness-to-pay for solar energy on a sample that was representative of Metro Manila to elicit their willingness-to-pay and a Single Bounded Dichotomous Choice and Double Bounded Dichotomous Choice analysis was used to estimate the amount they were willing to pay. The results showed that Metro Manila residents are willing to pay a premium on top of their current electricity bill amounting to US$5.71 (PHP268.42) – US$9.26 (PHP435.37) per month which is approximately 0.97% - 1.29% of their monthly household income. It was also discovered that besides higher income of households, a higher level of self-perceived knowledge on environmental awareness significantly affected the likelihood of a consumer to pay the premium. Shifting towards renewable energy is an expensive move not only for the government because of high capital investment but also to consumers; however, the Green Energy Option (a policy mechanism which gives consumers the option to decide where their electricity comes from) can potentially balance the shift of the economic burden by transitioning from a uniformly charged electricity rate to equitably charging consumers based on their willingness to pay for renewably sourced energy.Keywords: contingent valuation, dichotomous choice, Philippines, solar energy
Procedia PDF Downloads 33213362 Impact of Design Choices on the Life Cycle Energy of Modern Buildings
Authors: Mahsa Karimpour, Martin Belusko, Ke Xing, Frank Bruno
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Traditionally the embodied energy of design choices which reduce operational energy were assumed to have a negligible impact on the life cycle energy of buildings. However with new buildings having considerably lower operational energy, the significance of embodied energy increases. A life cycle assessment of a population of house designs was conducted in a mild and mixed climate zone. It was determined not only that embodied energy dominates life cycle energy, but that the impact on embodied of design choices was of equal significance to the impact on operational energy.Keywords: building life cycle energy, embodied energy, energy design measures, low energy buildings
Procedia PDF Downloads 76413361 From Theory to Practice: Teaching Rhetorical Theory for Effective Argumentative Essay Writing
Authors: Mohammad Ahmadi
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Argumentative writing is a highly opinion-based form of discourse that necessitates the ability to address commonly held opinions (endoxa). To enhance the development of persuasive, argumentative essays, the incorporation of classical rhetorical theory, with a specific focus on topics related to the canon of Invention (inventio), can be advantageous. This research investigates the practical application of rhetorical theory in teaching students how to construct compelling argumentative essays. The fundamental premise of this study is the limited familiarity of rhetoric and composition students with rhetorical theory. Consequently, this paper presents an effective pedagogical approach to introduce rhetorical theory to students, beginning from a foundational level. It delineates the procedures and progression that educators should adopt to elucidate and facilitate students' comprehension of rhetorical theory while demonstrating its utilization in the writing of an argumentative essay.Keywords: argumentative essay, rhetorical theory, pedagogy, invention
Procedia PDF Downloads 7313360 Simulation and Experimentation of Solar Thermal Collector for Air Heating System Using Dynamic Ribs
Authors: Nishitha Chowdary, Prabhav Dwivedi
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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 14713359 How to Evaluate Resting and Walking Energy Expenditures of Individuals with Different Body Mass Index
Authors: Zeynep Altinkaya, Ugur Dal, Figen Dag, Dilan D. Koyuncu, Merve Turkegun
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Obesity is defined as abnormal fat-tissue accumulation as a result of imbalance between energy intake and expenditure. Since 50-70% daily energy expenditure of sedantary individuals is consumed as resting energy expenditure (REE), it takes an important place in the evaluation of new methods for obesity treatment. Also, it is known that walking is a prevalent activity in the prevention of obesity. The primary purpose of this study is to evaluate and compare the resting and walking energy expenditures of individuals with different body mass index (BMI). In this research, 4 groups are formed as underweight (BMI < 18,5 kg/m2), normal (BMI=18,5-24,9 kg/m2), overweight (BMI=25-29,9 kg/m2), and obese (BMI ≥ 30) according to BMI of individuals. 64 healthy young adults (8 man and 8 woman per group, age 18-30 years) with no known gait disabilities were recruited in this study. The body compositions of all participants were measured via bioelectric empedance analysis method. The energy expenditure of individuals was measured with indirect calorimeter method as inspired and expired gas samples are collected breath-by-breath through a special facemask. The preferred walking speed (PWS) of each subject was determined by using infrared sensors placed in 2nd and 12th meters of 14 m walkway. The REE was measured for 15 min while subjects were lying, and walking energy expenditure was measured during subjects walk in their PWS on treadmill. The gross REE was significantly higher in obese subjects compared to underweight and normal subjects (p < 0,0001). When REE was normalized to body weight, it was higher in underweight and normal groups than overweight and obese groups (p < 0,0001). However, when REE was normalized to fat-free mass, it did not differ significantly between groups. The gross walking energy expenditure in PWS was higher in obese and overweight groups than underweight and normal groups (p < 0,0001). The regression coefficient between gross walking energy expenditure and body weight was significiant among normal and obese groups (p < 0.05). It accounted for 70,5% of gross walking energy expenditure in normal group, and 57,9% of gross walking energy expenditure in obese group. It is known that obese individuals have more metabolically inactive fat-tissue compared to other groups. While excess fat-tissue increases total body weight, it does not contribute much to REE. Therefore, REE results normalized to body weight could lead to misleading results. In order to eliminate fat-mass effect on REE of obese individuals, REE normalized to fat-free mass should be used to acquire more accurate results. On the other hand, the fat-mass increasement raises energy requirement while walking to retain the body balance. Thus, gross walking energy expenditure should be taken into consideration for the evaluating energy expenditure of walking.Keywords: body composition, obesity, resting energy expenditure, walking energy expenditure
Procedia PDF Downloads 38413358 Countercurrent Flow Simulation of Gas-Solid System in a Purge Column Using Computational Fluid Dynamics Techniques
Authors: T. J. Jamaleddine
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Purge columns or degasser vessels are widely used in the polyolefin process for removing trapped hydrocarbons and in-excess catalyst residues from the polymer particles. A uniform distribution of purged gases coupled with a plug-flow characteristic inside the column system is desirable to obtain optimum desorption characteristics of trapped hydrocarbon and catalyst residues. Computational Fluid Dynamics (CFD) approach is a promising tool for design optimization of these vessels. The success of this approach is profoundly dependent on the solution strategy and the choice of geometrical layout at the vessel outlet. Filling the column with solids and initially solving for the solids flow minimized numerical diffusion substantially. Adopting a cylindrical configuration at the vessel outlet resulted in less numerical instability and resembled the hydrodynamics flow of solids in the hopper segment reasonably well.Keywords: CFD, degasser vessel, gas-solids flow, gas purging, purge column, species transport
Procedia PDF Downloads 12113357 A Project Screening System for Energy Enterprise Based on Dempster-Shafer Theory
Authors: Woosik Jang, Seung Heon Han, Seung Won Baek
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Natural gas (NG) is an energy resource in a few countries, and most NG producers do business in politically unstable countries. In addition, as 90% of the LNG market is controlled by a small number of international oil companies (IOCs) and national oil companies (NOCs), entry of latecomers into the market is extremely limited. To meet these challenges, project viability needs to be assessed based on limited information from a project screening perspective. However, the early stages of the project have the following difficulties: (1) What are the factors to consider? (2) How many professionals do you need to decide? (3) How to make the best decision with limited information? To address this problem, this study proposes a model for evaluating LNG project viability based on the Dempster-Shafer theory (DST). A total of 11 indicators for analyzing the gas field, reflecting the characteristics of the LNG industry, and 23 indicators for analyzing the market environment, were identified. The proposed model also evaluates the LNG project based on the survey and provides uncertainty of the results based on DST as well as quantified results. Thus, the proposed model is expected to be able to support the decision-making process of the gas field project using quantitative results as a systematic framework, and it was developed as a stand-alone system to improve its usefulness in practice. Consequently, the amount of information and the mathematical approach are expected to improve the quality and opportunity of decision making for LNG projects for enterprises.Keywords: project screen, energy enterprise, decision support system, Dempster-Shafer theory
Procedia PDF Downloads 33513356 Energy Content and Spectral Energy Representation of Wave Propagation in a Granular Chain
Authors: Rohit Shrivastava, Stefan Luding
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A mechanical wave is propagation of vibration with transfer of energy and momentum. Studying the energy as well as spectral energy characteristics of a propagating wave through disordered granular media can assist in understanding the overall properties of wave propagation through inhomogeneous materials like soil. The study of these properties is aimed at modeling wave propagation for oil, mineral or gas exploration (seismic prospecting) or non-destructive testing for the study of internal structure of solids. The study of Energy content (Kinetic, Potential and Total Energy) of a pulse propagating through an idealized one-dimensional discrete particle system like a mass disordered granular chain can assist in understanding the energy attenuation due to disorder as a function of propagation distance. The spectral analysis of the energy signal can assist in understanding dispersion as well as attenuation due to scattering in different frequencies (scattering attenuation). The selection of one-dimensional granular chain also helps in studying only the P-wave attributes of the wave and removing the influence of shear or rotational waves. Granular chains with different mass distributions have been studied, by randomly selecting masses from normal, binary and uniform distributions and the standard deviation of the distribution is considered as the disorder parameter, higher standard deviation means higher disorder and lower standard deviation means lower disorder. For obtaining macroscopic/continuum properties, ensemble averaging has been used. Interpreting information from a Total Energy signal turned out to be much easier in comparison to displacement, velocity or acceleration signals of the wave, hence, indicating a better analysis method for wave propagation through granular materials. Increasing disorder leads to faster attenuation of the signal and decreases the Energy of higher frequency signals transmitted, but at the same time the energy of spatially localized high frequencies also increases. An ordered granular chain exhibits ballistic propagation of energy whereas, a disordered granular chain exhibits diffusive like propagation, which eventually becomes localized at long periods of time.Keywords: discrete elements, energy attenuation, mass disorder, granular chain, spectral energy, wave propagation
Procedia PDF Downloads 28113355 The Analysis of the Challenge China’s Energy Transition Faces and Proposed Solutions
Authors: Yuhang Wang
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As energy is vital to industrial productivity and human existence, ensuring energy security becomes a critical government responsibility. The Chinese government has implemented the energy transition to safeguard China’s energy security. Throughout this progression, the Chinese government has faced numerous obstacles. This article seeks to describe the causes of China’s energy transition barriers and the steps taken by the Chinese government to overcome them.Keywords: energy transition, energy market, fragmentation, path dependency
Procedia PDF Downloads 9113354 Comprehensive Study of Renewable Energy Resources and Present Scenario in India
Authors: Aparna Bhat, Rajeshwari Hegde
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Renewable energy sources also called non-conventional energy sources that are continuously replenished by natural processes. For example, solar energy, wind energy, bio-energy- bio-fuels grown sustain ably), hydropower etc., are some of the examples of renewable energy sources. A renewable energy system converts the energy found in sunlight, wind, falling-water, sea-waves, geothermal heat, or biomass into a form, we can use such as heat or electricity. Most of the renewable energy comes either directly or indirectly from sun and wind and can never be exhausted, and therefore they are called renewable. This paper presents a review about conventional and renewable energy scenario of India. The paper also presents current status, major achievements and future aspects of renewable energy in India and implementing renewable for the future is also been presented.Keywords: solar energy, renewabe energy, wind energy, bio-diesel, biomass, feedin
Procedia PDF Downloads 60013353 Constructal Enhancement of Fins Design Integrated to Phase Change Materials
Authors: Varun Joshi, Manish K. Rathod
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The latent heat thermal energy storage system is a thrust area of research due to exuberant thermal energy storage potential. The thermal performance of PCM is significantly augmented by installation of the high thermal conductivity fins. The objective of the present study is to obtain optimum size and location of the fins to enhance diffusion heat transfer without altering overall melting time. Hence, the constructal theory is employed to eliminate, resize, and re-position the fins. A numerical code based on conjugate heat transfer coupled enthalpy porosity approached is developed to solve Navier-Stoke and energy equation.The numerical results show that the constructal fin design has enhanced the thermal performance along with the increase in the overall volume of PCM when compared to conventional. The overall volume of PCM is found to be increased by half of total of volume of fins. The elimination and repositioning the fins at high temperature gradient from low temperature gradient is found to be vital.Keywords: constructal theory, enthalpy porosity approach, phase change materials, fins
Procedia PDF Downloads 17513352 Smart Energy Consumers: An Empirical Investigation on the Intention to Adopt Innovative Consumption Behaviour
Authors: Cecilia Perri, Vincenzo Corvello
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The aim of the present study is to investigate consumers' determinants of intention toward the adoption of Smart Grid solutions and technologies. Ajzen's Theory of Planned Behaviour (TPB) model is applied and tested to explain the formation of such adoption intention. An exogenous variable, taking into account the resistance to change of individuals, was added to the basic model. The elicitation study allowed obtaining salient modal beliefs, which were used, with the support of literature, to design the questionnaire. After the screening phase, data collected from the main survey were analysed for evaluating measurement model's reliability and validity. Consistent with the theory, the results of structural equation analysis revealed that attitude, subjective norm, and perceived behavioural control positively, which affected the adoption intention. Specifically, the variable with the highest estimate loading factor was found to be the perceived behavioural control, and, the most important belief related to each construct was determined (e.g., energy saving was observed to be the most significant belief linked with attitude). Further investigation indicated that the added exogenous variable has a negative influence on intention; this finding confirmed partially the hypothesis, since this influence was indirect: such relationship was mediated by attitude. Implications and suggestions for future research are discussed.Keywords: adoption of innovation, consumers behaviour, energy management, smart grid, theory of planned behaviour
Procedia PDF Downloads 40413351 Exploring Individual Decision Making Processes and the Role of Information Structure in Promoting Uptake of Energy Efficient Technologies
Authors: Rebecca J. Hafner, Daniel Read, David Elmes
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The current research applies decision making theory in order to address the problem of increasing uptake of energy-efficient technologies in the market place, where uptake is currently slower than one might predict following rational choice models. Specifically, in two studies we apply the alignable/non-alignable features effect and explore the impact of varying information structure on the consumers’ preference for standard versus energy efficient technologies. As researchers in the Interdisciplinary centre for Storage, Transformation and Upgrading of Thermal Energy (i-STUTE) are currently developing energy efficient heating systems for homes and businesses, we focus on the context of home heating choice, and compare preference for a standard condensing boiler versus an energy efficient heat pump, according to experimental manipulations in the structure of prior information. In Study 1, we find that people prefer stronger alignable features when options are similar; an effect which is mediated by an increased tendency to infer missing information is the same. Yet, in contrast to previous research, we find no effects of alignability on option preference when options differ. The advanced methodological approach used here, which is the first study of its kind to randomly allocate features as either alignable or non-alignable, highlights potential design effects in previous work. Study 2 is designed to explore the interaction between alignability and construal level as an explanation for the shift in attentional focus when options differ. Theoretical and applied implications for promoting energy efficient technologies are discussed.Keywords: energy-efficient technologies, decision-making, alignability effects, construal level theory, CO2 reduction
Procedia PDF Downloads 32713350 Isothermal Vapour-Liquid Equilibria of Binary Mixtures of 1, 2-Dichloroethane with Some Cyclic Ethers: Experimental Results and Modelling
Authors: Fouzia Amireche-Ziar, Ilham Mokbel, Jacques Jose
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The vapour pressures of the three binary mixtures: 1, 2- dichloroethane + 1,3-dioxolane, + 1,4-dioxane or + tetrahydropyrane, are carried out at ten temperatures ranging from 273 to 353.15 K. An accurate static device was employed for these measurements. The VLE data were reduced using the Redlich-Kister equation by taking into consideration the vapour pressure non-ideality in terms of the second molar virial coefficient. The experimental data were compared to the results predicted with the DISQUAC and Dortmund UNIFAC group contribution models for the total pressures P and the excess molar Gibbs energies GE.Keywords: disquac model, dortmund UNIFAC model, excess molar Gibbs energies GE, VLE
Procedia PDF Downloads 22513349 Drivers of Energy Saving Behaviour: The Relative Influence of Normative, Habitual, Intentional, and Situational Processes
Authors: Karlijn Van Den Broek, Ian Walker, Christian Klöckner
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Campaigns aiming to induce energy-saving behaviour among householders use a wide range of approaches that address many different drivers thought to underpin this behaviour. However, little research has compared the relative importance of the different factors that influence energy behaviour, meaning campaigns are not informed about where best to focus resources. Therefore, this study applies the Comprehensive Action Determination Model (CADM) to compare the role of normative, intentional, habitual, and situational processes on energy-saving behaviour. An online survey on a sample of households (N = 247) measured the CADM variables and the data was analysed using structural equation modelling. Results showed that situational and habitual processes were best able to account for energy saving behaviour while normative and intentional processes had little predictive power. These findings suggest that policymakers should move away from motivating householders to save energy and should instead focus their efforts on changing energy habits and creating environments that facilitate energy saving behaviour. These findings add to the wider development in social and environmental psychology that emphasizes the importance of extra-personal variables such as the physical environment in shaping behaviour.Keywords: energy consumption, behavioural modelling, environmental psychology theory, habits, values
Procedia PDF Downloads 24113348 Experimental and Numerical Study of the Thermomagnetic Convection of Ferrofluid Driven by Non-Uniform Magnetic Field around a Current-Carrying Wire
Authors: Ashkan Vatani, Petere Woodfiel, Nam-Trung Nguyen, Dzung Dao
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Thermomagnetic convection of a ferrofluid flow induced by the non-uniform magnetic field around a current-carrying wire was theoretically analyzed, numerically studied and experimentally validated. The dependency of the thermomagnetic convection on the current and fluid temperature has been studied. The Nusselt number for a heated 50um diameter wire in the ferrofluid exponentially scales with applied current to the micro-wire. This result is in good agreement with the correlated Nusselt number by curve-fitting the experimental data at different fluid temperatures. It was shown that at low currents, no significance is observed for thermomagnetic convection rather than the buoyancy-driven convection, while the thermomagnetic convection becomes dominant at high currents. Also, numerical simulations showed a promising cooling ability for large scale applications.Keywords: ferrofluid, non-uniform magnetic field, Nusselt number, thermomagnetic convection
Procedia PDF Downloads 24113347 Microwave Dielectric Relaxation Study of Diethanolamine with Triethanolamine from 10 MHz-20 GHz
Authors: A. V. Patil
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The microwave dielectric relaxation study of diethanolamine with triethanolamine binary mixture have been determined over the frequency range of 10 MHz to 20 GHz, at various temperatures using time domain reflectometry (TDR) method for 11 concentrations of the system. The present work reveals molecular interaction between same multi-functional groups [−OH and –NH2] of the alkanolamines (diethanolamine and triethanolamine) using different models such as Debye model, Excess model, and Kirkwood model. The dielectric parameters viz. static dielectric constant (ε0) and relaxation time (τ) have been obtained with Debye equation characterized by a single relaxation time without relaxation time distribution by the least squares fit method.Keywords: diethanolamine, excess properties, kirkwood properties, time domain reflectometry, triethanolamine
Procedia PDF Downloads 29513346 Gravitational Frequency Shifts for Photons and Particles
Authors: Jing-Gang Xie
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The research, in this case, considers the integration of the Quantum Field Theory and the General Relativity Theory. As two successful models in explaining behaviors of particles, they are incompatible since they work at different masses and scales of energy, with the evidence that regards the description of black holes and universe formation. It is so considering previous efforts in merging the two theories, including the likes of the String Theory, Quantum Gravity models, and others. In a bid to prove an actionable experiment, the paper’s approach starts with the derivations of the existing theories at present. It goes on to test the derivations by applying the same initial assumptions, coupled with several deviations. The resulting equations get similar results to those of classical Newton model, quantum mechanics, and general relativity as long as conditions are normal. However, outcomes are different when conditions are extreme, specifically with no breakdowns even for less than Schwarzschild radius, or at Planck length cases. Even so, it proves the possibilities of integrating the two theories.Keywords: general relativity theory, particles, photons, Quantum Gravity Model, gravitational frequency shift
Procedia PDF Downloads 35413345 Bio Energy from Metabolic Activity of Bacteria in Plant and Soil Using Novel Microbial Fuel Cells
Authors: B. Samuel Raj, Solomon R. D. Jebakumar
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Microbial fuel cells (MFCs) are an emerging and promising method for achieving sustainable energy since they can remove contaminated organic matter and simultaneously generate electricity. Our approach was driven in three different ways like Bacterial fuel cell, Soil Microbial fuel cell (Soil MFC) and Plant Microbial fuel cell (Plant MFC). Bacterial MFC: Sulphate reducing bacteria (SRB) were isolated and identified as the efficient electricigens which is able to produce ±2.5V (689mW/m2) and it has sustainable activity for 120 days. Experimental data with different MFC revealed that high electricity production harvested continuously for 90 days 1.45V (381mW/m2), 1.98V (456mW/m2) respectively. Biofilm formation was confirmed on the surface of the anode by high content screening (HCS) and scanning electron Microscopic analysis (SEM). Soil MFC: Soil MFC was constructed with low cost and standard Mudwatt soil MFC was purchased from keegotech (USA). Vermicompost soil (V1) produce high energy (± 3.5V for ± 400 days) compared to Agricultural soil (A1) (± 2V for ± 150 days). Biofilm formation was confirmed by HCS and SEM analysis. This finding provides a method for extracting energy from organic matter, but also suggests a strategy for promoting the bioremediation of organic contaminants in subsurface environments. Our Soil MFC were able to run successfully a 3.5V fan and three LED continuously for 150 days. Plant MFC: Amaranthus candatus (P1) and Triticum aestivium (P2) were used in Plant MFC to confirm the electricity production from plant associated microbes, four uniform size of Plant MFC were constructed and checked for energy production. P2 produce high energy (± 3.2V for 40 days) with harvesting interval of two times and P1 produces moderate energy without harvesting interval (±1.5V for 24 days). P2 is able run 3.5V fan continuously for 10days whereas P1 needs optimization of growth conditions to produce high energy.Keywords: microbial fuel cell, biofilm, soil microbial fuel cell, plant microbial fuel cell
Procedia PDF Downloads 34313344 A Study on Game Theory Approaches for Wireless Sensor Networks
Authors: M. Shoukath Ali, Rajendra Prasad Singh
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Game Theory approaches and their application in improving the performance of Wireless Sensor Networks (WSNs) are discussed in this paper. The mathematical modeling and analysis of WSNs may have low success rate due to the complexity of topology, modeling, link quality, etc. However, Game Theory is a field, which can efficiently use to analyze the WSNs. Game Theory is related to applied mathematics that describes and analyzes interactive decision situations. Game theory has the ability to model independent, individual decision makers whose actions affect the surrounding decision makers. The outcome of complex interactions among rational entities can be predicted by a set of analytical tools. However, the rationality demands a stringent observance to a strategy based on measured of perceived results. Researchers are adopting game theory approaches to model and analyze leading wireless communication networking issues, which includes QoS, power control, resource sharing, etc.Keywords: wireless sensor network, game theory, cooperative game theory, non-cooperative game theory
Procedia PDF Downloads 42113343 Study of Electron Cyclotron Resonance Acceleration by Cylindrical TE₀₁₁ Mode
Authors: Oswaldo Otero, Eduardo A. Orozco, Ana M. Herrera
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In this work, we present results from analytical and numerical studies of the electron acceleration by a TE₀₁₁ cylindrical microwave mode in a static homogeneous magnetic field under electron cyclotron resonance (ECR) condition. The stability of the orbits is analyzed using the particle orbit theory. In order to get a better understanding of the interaction wave-particle, we decompose the azimuthally electric field component as the superposition of right and left-hand circular polarization standing waves. The trajectory, energy and phase-shift of the electron are found through a numerical solution of the relativistic Newton-Lorentz equation in a finite difference method by the Boris method. It is shown that an electron longitudinally injected with an energy of 7 keV in a radial position r=Rc/2, being Rc the cavity radius, is accelerated up to energy of 90 keV by an electric field strength of 14 kV/cm and frequency of 2.45 GHz. This energy can be used to produce X-ray for medical imaging. These results can be used as a starting point for study the acceleration of electrons in a magnetic field changing slowly in time (GYRAC), which has some important applications as the electron cyclotron resonance ion proton accelerator (ECR-IPAC) for cancer therapy and to control plasma bunches with relativistic electrons.Keywords: Boris method, electron cyclotron resonance, finite difference method, particle orbit theory, X-ray
Procedia PDF Downloads 15413342 Prediction of the Dark Matter Distribution and Fraction in Individual Galaxies Based Solely on Their Rotation Curves
Authors: Ramzi Suleiman
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Recently, the author proposed an observationally-based relativity theory termed information relativity theory (IRT). The theory is simple and is based only on basic principles, with no prior axioms and no free parameters. For the case of a body of mass in uniform rectilinear motion relative to an observer, the theory transformations uncovered a matter-dark matter duality, which prescribes that the sum of the densities of the body's baryonic matter and dark matter, as measured by the observer, is equal to the body's matter density at rest. It was shown that the theory transformations were successful in predicting several important phenomena in small particle physics, quantum physics, and cosmology. This paper extends the theory transformations to the cases of rotating disks and spheres. The resulting transformations for a rotating disk are utilized to derive predictions of the radial distributions of matter and dark matter densities in rotationally supported galaxies based solely on their observed rotation curves. It is also shown that for galaxies with flattening curves, good approximations of the radial distributions of matter and dark matter and of the dark matter fraction could be obtained from one measurable scale radius. Test of the model on five galaxies, chosen randomly from the SPARC database, yielded impressive predictions. The rotation curves of all the investigated galaxies emerged as accurate traces of the predicted radial density distributions of their dark matter. This striking result raises an intriguing physical explanation of gravity in galaxies, according to which it is the proximal drag of the stars and gas in the galaxy by its rotating dark matter web. We conclude by alluding briefly to the application of the proposed model to stellar systems and black holes. This study also hints at the potential of the discovered matter-dark matter duality in fixing the standard model of elementary particles in a natural manner without the need for hypothesizing about supersymmetric particles.Keywords: dark matter, galaxies rotation curves, SPARC, rotating disk
Procedia PDF Downloads 7213341 Cladding Technology for Metal-Hybrid Composites with Network-Structure
Authors: Ha-Guk Jeong, Jong-Beom Lee
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Cladding process is very typical technology for manufacturing composite materials by the hydrostatic extrusion. Because there is no friction between the metal and the container, it can be easily obtained in uniform flow during the deformation. The general manufacturing process for a metal-matrix composite in the solid state, mixing metal powders and ceramic powders with a suited volume ratio, prior to be compressed or extruded at the cold or hot condition in a can. Since through a plurality of unit processing steps of dispersing the materials having a large difference in their characteristics and physical mixing, the process is complicated and leads to non-uniform dispersion of ceramics. It is difficult and hard to reach a uniform ideal property in the coherence problems at the interface between the metal and the ceramic reinforcements. Metal hybrid composites, which presented in this report, are manufactured through the traditional plastic deformation processes like hydrostatic extrusion, caliber-rolling, and drawing. By the previous process, the realization of uniform macro and microstructure is surely possible. In this study, as a constituent material, aluminum, copper, and titanium have been used, according to the component ratio, excellent characteristics of each material were possible to produce a metal hybrid composite that appears to maximize. MgB₂ superconductor wire also fabricated via the same process. It will be introduced to their unique artistic and thermal characteristics.Keywords: cladding process, metal-hybrid composites, hydrostatic extrusion, electronic/thermal characteristics
Procedia PDF Downloads 17313340 Design of Non-uniform Circular Antenna Arrays Using Firefly Algorithm for Side Lobe Level Reduction
Authors: Gopi Ram, Durbadal Mandal, Rajib Kar, Sakti Prasad Ghoshal
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A design problem of non-uniform circular antenna arrays for maximum reduction of both the side lobe level (SLL) and first null beam width (FNBW) is dealt with. This problem is modeled as a simple optimization problem. The method of Firefly algorithm (FFA) is used to determine an optimal set of current excitation weights and antenna inter-element separations that provide radiation pattern with maximum SLL reduction and much improvement on FNBW as well. Circular array antenna laid on x-y plane is assumed. FFA is applied on circular arrays of 8-, 10-, and 12- elements. Various simulation results are presented and hence performances of side lobe and FNBW are analyzed. Experimental results show considerable reductions of both the SLL and FNBW with respect to those of the uniform case and some standard algorithms GA, PSO, and SA applied to the same problem.Keywords: circular arrays, first null beam width, side lobe level, FFA
Procedia PDF Downloads 24813339 Leadership Styles and Adoption of Risk Governance in Insurance and Energy Industry: A Comparative Case Study
Authors: Ruchi Agarwal
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In today’s world, companies are operating in dynamic, uncertain and ambiguous business environments. Globally, more companies are failing due to Environmental, Social and Governance (ESG) factors than ever. Corporate governance and risk management are intertwined in nature. For decades, corporate governance and risk management have been influenced by internal and external factors. Three schools of thought have influenced risk governance for decades: Agency theory, Contingency theory, and Institutional theory. Agency theory argues that agents have interests conflicting with principal interests and the information problem. Contingency theory suggests that risk management adoption is influenced by internal and external factors, while Institutional theory suggests that organizations legitimize risk management with regulators, competitors, and professional bodies. The conflicting objectives of theories have created problems for executives in organizations in the adoption of Risk Governance. So far, there are many studies that discussed risk culture and the role of actors in risk governance, but there are rare studies discussing the role of risk culture in the adoption of risk governance from a leadership style perspective. This study explores the adoption of risk governance in two contrasting industries, such as the Insurance and energy business, to understand whether risk governance is influenced by internal/external factors or whether risk culture is influenced by leaders. We draw empirical evidence by comparing the cases of an Indian insurance company and a renewable energy-based firm in India. We interviewed more than 20 senior executives of companies and collected annual reports, risk management policies, and more than 10 PPTs and other reports from 2017 to 2024. We visited the company for follow-up questions several times. The findings of my research revealed that both companies have used risk governance for strategic renewal of the company. Insurance companies use a transactional leadership style based on performance and reward for improving risk, while energy companies use rather symbolic management to make debt restructuring meaningful for stakeholders. Overall, both companies turned from loss-making to profitable ones in a few years. This comparative study highlights the role of different leadership styles in the adoption of risk governance. The study is also distinct as previous research rarely studied risk governance in two contrasting industries in reference to leadership styles.Keywords: leadership style, corporate governance, risk management, risk culture, strategic renewal
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