Search results for: regional climate model
15203 Ecorium: The Ecological Project in Montevideo Uruguay
Authors: Chettou Souhaila, Soufi Omar, Roumia Mohammed Ammar
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Protecting the environment is to preserve the survival and future of humanity. Indeed, the environment is our source of food and drinking water, the air is our source of oxygen, the climate allows our survival and biodiversity are a potential drug reservoir. Preserving the environment is, therefore, a matter of survival. The objective of this project is to familiarize the general public with environmental problems not only with the theme of environmental protection, but also with the concept of biodiversity in different ecosystems. For it, the aim of our project was to create the Ecorium which is a place that preserves many species of plants of different ecosystems, schools, malls, buildings, offices, ecological transports, gardens, and many familial activities that participated in the ecosystems development, strategic biodiversity and sustainable development.Keywords: ecological system, ecorium, environment, sustainable development
Procedia PDF Downloads 32715202 A Dynamic Software Product Line Approach to Self-Adaptive Genetic Algorithms
Authors: Abdelghani Alidra, Mohamed Tahar Kimour
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Genetic algorithm must adapt themselves at design time to cope with the search problem specific requirements and at runtime to balance exploration and convergence objectives. In a previous article, we have shown that modeling and implementing Genetic Algorithms (GA) using the software product line (SPL) paradigm is very appreciable because they constitute a product family sharing a common base of code. In the present article we propose to extend the use of the feature model of the genetic algorithms family to model the potential states of the GA in what is called a Dynamic Software Product Line. The objective of this paper is the systematic generation of a reconfigurable architecture that supports the dynamic of the GA and which is easily deduced from the feature model. The resultant GA is able to perform dynamic reconfiguration autonomously to fasten the convergence process while producing better solutions. Another important advantage of our approach is the exploitation of recent advances in the domain of dynamic SPLs to enhance the performance of the GAs.Keywords: self-adaptive genetic algorithms, software engineering, dynamic software product lines, reconfigurable architecture
Procedia PDF Downloads 27015201 Numerical Model for Investigation of Recombination Mechanisms in Graphene-Bonded Perovskite Solar Cells
Authors: Amir Sharifi Miavaghi
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It is believed recombination mechnisms in graphene-bonded perovskite solar cells based on numerical model in which doped-graphene structures are employed as anode/cathode bonding semiconductor. Moreover, the dark-light current density-voltage density-voltage curves are investigated by regression analysis. Loss mechanisms such as back contact barrier, deep surface defect in the adsorbent layer is determined by adapting the simulated cell performance to the measurements using the differential evolution of the global optimization algorithm. The performance of the cell in the connection process includes J-V curves that are examined at different temperatures and open circuit voltage (V) under different light intensities as a function of temperature. Based on the proposed numerical model and the acquired loss mechanisms, our approach can be used to improve the efficiency of the solar cell further. Due to the high demand for alternative energy sources, solar cells are good alternatives for energy storage using the photovoltaic phenomenon.Keywords: numerical model, recombination mechanism, graphen, perovskite solarcell
Procedia PDF Downloads 5915200 Study of Mixed Convection in a Vertical Channel Filled with a Reactive Porous Medium in the Absence of Local Thermal Equilibrium
Authors: Hamid Maidat, Khedidja Bouhadef, Djamel Eddine Ameziani, Azzedine Abdedou
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This work consists of a numerical simulation of convective heat transfer in a vertical plane channel filled with a heat generating porous medium, in the absence of local thermal equilibrium. The walls are maintained to a constant temperature and the inlet velocity is uniform. The dynamic range is described by the Darcy-Brinkman model and the thermal field by two energy equations model. A dimensionless formulation is developed for performing a parametric study based on certain dimensionless groups such as, the Biot interstitial number, the thermal conductivity ratio and the volumetric heat generation. The governing equations are solved using the finite volume method, gave rise to a multitude of results concerning in particular the thermal field in the porous channel and the existence or not of the local thermal equilibrium.Keywords: local thermal non equilibrium model, mixed convection, porous medium, power generation
Procedia PDF Downloads 59915199 Sustainable Desert Traditional Architecture of the Central Region of Saudi Arabia
Authors: Hisham Mortada
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For thousands of years mud houses have represented the practical wisdom and spirituality of people, particularly those of desert regions, who learned how to use local materials to build homes that fitted the environmental and cultural conditions which they lived in. As a case study, the central region of Saudi Arabia exhibits a tradition of earth architecture that is unique in style, culture and sustainability. Aiming to contribute towards the local debate of the suitability of the traditional mud architecture for today’s lifestyle of Saudis, this paper explores the sustainable nature of the traditional adobe architecture of this hot arid region from environmental, social and technical points of view.Keywords: desert architecture, alternative materials, Saudi Arabia, arid climate, green architecture
Procedia PDF Downloads 36615198 Validation and Fit of a Biomechanical Bipedal Walking Model for Simulation of Loads Induced by Pedestrians on Footbridges
Authors: Dianelys Vega, Carlos Magluta, Ney Roitman
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The simulation of loads induced by walking people in civil engineering structures is still challenging It has been the focus of considerable research worldwide in the recent decades due to increasing number of reported vibration problems in pedestrian structures. One of the most important key in the designing of slender structures is the Human-Structure Interaction (HSI). How moving people interact with structures and the effect it has on their dynamic responses is still not well understood. To rely on calibrated pedestrian models that accurately estimate the structural response becomes extremely important. However, because of the complexity of the pedestrian mechanisms, there are still some gaps in knowledge and more reliable models need to be investigated. On this topic several authors have proposed biodynamic models to represent the pedestrian, whether these models provide a consistent approximation to physical reality still needs to be studied. Therefore, this work comes to contribute to a better understanding of this phenomenon bringing an experimental validation of a pedestrian walking model and a Human-Structure Interaction model. In this study, a bi-dimensional bipedal walking model was used to represent the pedestrians along with an interaction model which was applied to a prototype footbridge. Numerical models were implemented in MATLAB. In parallel, experimental tests were conducted in the Structures Laboratory of COPPE (LabEst), at Federal University of Rio de Janeiro. Different test subjects were asked to walk at different walking speeds over instrumented force platforms to measure the walking force and an accelerometer was placed at the waist of each subject to measure the acceleration of the center of mass at the same time. By fitting the step force and the center of mass acceleration through successive numerical simulations, the model parameters are estimated. In addition, experimental data of a walking pedestrian on a flexible structure was used to validate the interaction model presented, through the comparison of the measured and simulated structural response at mid span. It was found that the pedestrian model was able to adequately reproduce the ground reaction force and the center of mass acceleration for normal and slow walking speeds, being less efficient for faster speeds. Numerical simulations showed that biomechanical parameters such as leg stiffness and damping affect the ground reaction force, and the higher the walking speed the greater the leg length of the model. Besides, the interaction model was also capable to estimate with good approximation the structural response, that remained in the same order of magnitude as the measured response. Some differences in frequency spectra were observed, which are presumed to be due to the perfectly periodic loading representation, neglecting intra-subject variabilities. In conclusion, this work showed that the bipedal walking model could be used to represent walking pedestrians since it was efficient to reproduce the center of mass movement and ground reaction forces produced by humans. Furthermore, although more experimental validations are required, the interaction model also seems to be a useful framework to estimate the dynamic response of structures under loads induced by walking pedestrians.Keywords: biodynamic models, bipedal walking models, human induced loads, human structure interaction
Procedia PDF Downloads 12515197 The Use of Scuba Diving Tourism for Marine Protected Area Management
Authors: L. Mota, O. Frausto
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Marine Protected Areas can benefit from nature based tourism, monitoring environmental impacts and also become target for human presence. From more than 3 million tourists visiting Cozumel Island every year, an average of 2,8 million arrive by cruise ship, and 41% are estimated to have motivation for water activities. The destination is relying so much on the tourism activity, that scuba diving and snorkeling in the National Park Reef of Cozumel sustain the major economic activity. In order to achieve the sustainable development indicator designed for regional environmental development, the PNAC offers a training course for tourism providers acceding the protected area. This way, the update of the last 5 years of such training is directed to diving staff, boat crew and professionals, making them able to assist in managing the natural resource. Moreover, the case study is an example to be used for raising awareness among tourists visiting protected areas.Keywords: education, marine protected area, scuba diving, sustainability, tourism
Procedia PDF Downloads 43515196 Finite Element Modeling of Friction Stir Welding of Dissimilar Alloys
Authors: Fadi Al-Badour, Nesar Merah, Abdelrahman Shuaib, Abdelaziz Bazoune
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In the current work, a Coupled Eulerian Lagrangian (CEL) model is developed to simulate the friction stir welding (FSW) process of dissimilar Aluminum alloys (Al 6061-T6 with Al 5083-O). The model predicts volumetric defects, material flow, developed temperatures, and stresses in addition to tool reaction loads. Simulation of welding phase is performed by employing a control volume approach, whereas the welding speed is defined as inflow and outflow over Eulerian domain boundaries. Only material softening due to inelastic heat generation is considered and material behavior is assumed to obey Johnson-Cook’s Model. The model was validated using published experimentally measured temperatures, at similar welding conditions, and by qualitative comparison of dissimilar weld microstructure. The FE results showed that most of developed temperatures were below melting and that the bulk of the deformed material in solid state. The temperature gradient on AL6061-T6 side was found to be less than that of Al 5083-O. Changing the position Al 6061-T6 from retreating (Ret.) side to advancing (Adv.) side led to a decrease in maximum process temperature and strain rate. This could be due to the higher resistance of Al 6061-T6 to flow as compared to Al 5083-O.Keywords: friction stir welding, dissimilar metals, finite element modeling, coupled Eulerian Lagrangian Analysis
Procedia PDF Downloads 32215195 Comparison of Spiking Neuron Models in Terms of Biological Neuron Behaviours
Authors: Fikret Yalcinkaya, Hamza Unsal
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To understand how neurons work, it is required to combine experimental studies on neural science with numerical simulations of neuron models in a computer environment. In this regard, the simplicity and applicability of spiking neuron modeling functions have been of great interest in computational neuron science and numerical neuroscience in recent years. Spiking neuron models can be classified by exhibiting various neuronal behaviors, such as spiking and bursting. These classifications are important for researchers working on theoretical neuroscience. In this paper, three different spiking neuron models; Izhikevich, Adaptive Exponential Integrate Fire (AEIF) and Hindmarsh Rose (HR), which are based on first order differential equations, are discussed and compared. First, the physical meanings, derivatives, and differential equations of each model are provided and simulated in the Matlab environment. Then, by selecting appropriate parameters, the models were visually examined in the Matlab environment and it was aimed to demonstrate which model can simulate well-known biological neuron behaviours such as Tonic Spiking, Tonic Bursting, Mixed Mode Firing, Spike Frequency Adaptation, Resonator and Integrator. As a result, the Izhikevich model has been shown to perform Regular Spiking, Continuous Explosion, Intrinsically Bursting, Thalmo Cortical, Low-Threshold Spiking and Resonator. The Adaptive Exponential Integrate Fire model has been able to produce firing patterns such as Regular Ignition, Adaptive Ignition, Initially Explosive Ignition, Regular Explosive Ignition, Delayed Ignition, Delayed Regular Explosive Ignition, Temporary Ignition and Irregular Ignition. The Hindmarsh Rose model showed three different dynamic neuron behaviours; Spike, Burst and Chaotic. From these results, the Izhikevich cell model may be preferred due to its ability to reflect the true behavior of the nerve cell, the ability to produce different types of spikes, and the suitability for use in larger scale brain models. The most important reason for choosing the Adaptive Exponential Integrate Fire model is that it can create rich ignition patterns with fewer parameters. The chaotic behaviours of the Hindmarsh Rose neuron model, like some chaotic systems, is thought to be used in many scientific and engineering applications such as physics, secure communication and signal processing.Keywords: Izhikevich, adaptive exponential integrate fire, Hindmarsh Rose, biological neuron behaviours, spiking neuron models
Procedia PDF Downloads 17115194 Developing Heat-Power Efficiency Criteria for Characterization of Technosphere Structural Elements
Authors: Victoria Y. Garnova, Vladimir G. Merzlikin, Sergey V. Khudyakov, Aleksandr A. Gajour, Andrei P. Garnov
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This paper refers to the analysis of the characteristics of industrial and lifestyle facilities heat- energy objects as a part of the thermal envelope of Earth's surface for inclusion in any database of economic forecasting. The idealized model of the Earth's surface is discussed. This model gives the opportunity to obtain the energy equivalent for each element of terrain and world ocean. Energy efficiency criterion of comfortable human existence is introduced. Dynamics of changes of this criterion offers the possibility to simulate the possible technogenic catastrophes with a spontaneous industrial development of the certain Earth areas. Calculated model with the confirmed forecast of the Gulf Stream freezing in the Polar Regions in 2011 due to the heat-energy balance disturbance for the oceanic subsurface oil polluted layer is given. Two opposing trends of human development under the limited and unlimited amount of heat-energy resources are analyzed.Keywords: Earth's surface, heat-energy consumption, energy criteria, technogenic catastrophes
Procedia PDF Downloads 31115193 A Case Study at PT Bank XYZ on The Role of Compensation, Career Development, and Employee Engagement towards Employee Performance
Authors: Ahmad Badawi Saluy, Novawiguna Kemalasari
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This study aims to examine, analyze and explain the impacts of compensation, career development and employee engagement to employee’s performance partially and simultaneously (Case Study at PT Bank XYZ). The research design used is quantitative descriptive research causality involving 30 respondents. Sources of data are from primary and secondary data, primary data obtained from questionnaires distribution and secondary data obtained from journals and books. Data analysis used model test using smart application PLS 3 that consists of test outer model and inner model. The results showed that compensation, career development and employee engagement partially have a positive impact on employee performance, while they have a positive and significant impact on employee performance simultaneously. The independent variable has the greatest impact is the employee engagement.Keywords: compensation, career development, employee engagement, employee performance
Procedia PDF Downloads 14415192 Generic Hybrid Models for Two-Dimensional Ultrasonic Guided Wave Problems
Authors: Manoj Reghu, Prabhu Rajagopal, C. V. Krishnamurthy, Krishnan Balasubramaniam
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A thorough understanding of guided ultrasonic wave behavior in structures is essential for the application of existing Non Destructive Evaluation (NDE) technologies, as well as for the development of new methods. However, the analysis of guided wave phenomena is challenging because of their complex dispersive and multimodal nature. Although numerical solution procedures have proven to be very useful in this regard, the increasing complexity of features and defects to be considered, as well as the desire to improve the accuracy of inspection often imposes a large computational cost. Hybrid models that combine numerical solutions for wave scattering with faster alternative methods for wave propagation have long been considered as a solution to this problem. However usually such models require modification of the base code of the solution procedure. Here we aim to develop Generic Hybrid models that can be directly applied to any two different solution procedures. With this goal in mind, a Numerical Hybrid model and an Analytical-Numerical Hybrid model has been developed. The concept and implementation of these Hybrid models are discussed in this paper.Keywords: guided ultrasonic waves, Finite Element Method (FEM), Hybrid model
Procedia PDF Downloads 45315191 Numerical Modeling of Timber Structures under Varying Humidity Conditions
Authors: Sabina Huč, Staffan Svensson, Tomaž Hozjan
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Timber structures may be exposed to various environmental conditions during their service life. Often, the structures have to resist extreme changes in the relative humidity of surrounding air, with simultaneously carrying the loads. Wood material response for this load case is seen as increasing deformation of the timber structure. Relative humidity variations cause moisture changes in timber and consequently shrinkage and swelling of the material. Moisture changes and loads acting together result in mechano-sorptive creep, while sustained load gives viscoelastic creep. In some cases, magnitude of the mechano-sorptive strain can be about five times the elastic strain already at low stress levels. Therefore, analyzing mechano-sorptive creep and its influence on timber structures’ long-term behavior is of high importance. Relatively many one-dimensional rheological models for rheological behavior of wood can be found in literature, while a number of models coupling creep response in each material direction is limited. In this study, mathematical formulation of a coupled two-dimensional mechano-sorptive model and its application to the experimental results are presented. The mechano-sorptive model constitutes of a moisture transport model and a mechanical model. Variation of the moisture content in wood is modelled by multi-Fickian moisture transport model. The model accounts for processes of the bound-water and water-vapor diffusion in wood, that are coupled through sorption hysteresis. Sorption defines a nonlinear relation between moisture content and relative humidity. Multi-Fickian moisture transport model is able to accurately predict unique, non-uniform moisture content field within the timber member over time. Calculated moisture content in timber members is used as an input to the mechanical analysis. In the mechanical analysis, the total strain is assumed to be a sum of the elastic strain, viscoelastic strain, mechano-sorptive strain, and strain due to shrinkage and swelling. Mechano-sorptive response is modelled by so-called spring-dashpot type of a model, that proved to be suitable for describing creep of wood. Mechano-sorptive strain is dependent on change of moisture content. The model includes mechano-sorptive material parameters that have to be calibrated to the experimental results. The calibration is made to the experiments carried out on wooden blocks subjected to uniaxial compressive loaded in tangential direction and varying humidity conditions. The moisture and the mechanical model are implemented in a finite element software. The calibration procedure gives the required, distinctive set of mechano-sorptive material parameters. The analysis shows that mechano-sorptive strain in transverse direction is present, though its magnitude and variation are substantially lower than the mechano-sorptive strain in the direction of loading. The presented mechano-sorptive model enables observing real temporal and spatial distribution of the moisture-induced strains and stresses in timber members. Since the model’s suitability for predicting mechano-sorptive strains is shown and the required material parameters are obtained, a comprehensive advanced analysis of the stress-strain state in timber structures, including connections subjected to constant load and varying humidity is possible.Keywords: mechanical analysis, mechano-sorptive creep, moisture transport model, timber
Procedia PDF Downloads 23715190 Reframing Service Sector Privatisation Quality Conception with the Theory of Deferred Action
Authors: Mukunda Bastola, Frank Nyame-Asiamah
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Economics explanation for privatisation, drawing on neo-liberal market structures and technical efficiency principles has failed to address social imbalance and, distribute the efficiency benefits accrued from privatisation equitably among service users and different classes of people in society. Stakeholders’ interest, which cover ethical values and changing human needs are ignored due to shareholders’ profit maximising strategy with higher service charges. The consequence of these is that, the existing justifications for privatisation have fallen short of customer quality expectations because the underlying plan-based models fail to account for the nuances of customer expectations. We draw on the theory of deferred action to develop a context-based privatisation model, the deferred-based privatisation model, to explain how privatisation could be strategised for the emergent reality of the wider stakeholders’ interests and everyday quality demands of customers which are unpredictable.Keywords: privatisation, service quality, shareholders, deferred action, deferred-based privatisation model
Procedia PDF Downloads 26315189 Household Level Determinants of Rural-Urban Migration in Bangladesh
Authors: Shamima Akhter, Siegfried Bauer
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The aim of this study is to analyze the migration process of the rural population of Bangladesh. Heckman Probit model with sample selection was applied in this paper to explore the determinants of migration and intensity of migration at farm household level. The farm survey was conducted in the central part of Bangladesh on 160 farm households with migrant and on 154 farm households without migrant including a total of 316 farm households. The results from the applied model revealed that main determinants of migration at farm household level are household age, economically active males and females, number of young and old dependent members in the household and agricultural land holding. On the other hand, the main determinants of intensity of migration are availability of economically adult male in the household, number of young dependents and agricultural land holding.Keywords: determinants, Heckman Probit model, migration, rural-urban
Procedia PDF Downloads 29815188 Exact Phase Diagram of High-TC Superconductors
Authors: Abid Boudiar
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We propose a simple model to obtain an exact expression of Tc/(Tc,max) for the temperature-doping phase diagram of superconducting cuprates. We showed that our model predicted most phase diagram scenario. We found the exact special doping points p(opt), p(qcp) and an accurate E(g,max). Some other properties such as the stripes length 100.1°A and the energy gap in cuprates chain 6meV can also be calculated exactly. Another interesting consequence of this simple picture is the new magic numbers and the ability to express everything using a (Tc,p) diagram via the golden ratio.Keywords: superconducting cuprates, phase, pseudogap, hole doping, strips, golden ratio, soliton
Procedia PDF Downloads 46415187 Behavioral Assessment of the Role of Brain 5-HT4 Receptors on the Memory and Cognitive Performance in a Rat Model of Alzheimer Disease
Authors: Siamak Shahidi, Nasrin Hashemi-Firouzi, Sara Soleimani-Asl, Alireza Komaki
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Introduction: Alzheimer's disease (AD) is a neurodegenerative disorder characterized by progressive memory and cognitive performance. Recently, an involvement of the serotonergic system and their receptors are suspected in the AD progression. In the present behavioral study, the effects of BIMU (selective 5-HT4 receptor agonist) on cognition and memory in the rat model of AD was investigated. Material and Methods: The animal model of the AD was induced by intracerebroventricular (Icv) injection of amyloid beta (Aβ) in adult male Wistar rats. Animals were divided into experimental groups included control, sham, Aβ, Aβ +BIMU groups. The treatment substances were icv injected (1 μg/μL) for thirty consecutive days. Then, novel object recognition (NOR) and passive avoidance learning (PAL) tests were applied to investigate memory and cognitive performance. Results: Aβ decrease the discrimination index of NOR test. Also, it increases the time spent in the dark compartment during PAL test, as compared with sham and control groups. In addition, compared to Aβ groups, BIMU significantly increased the discrimination index of NOR test and decreased the time spent in the dark compartment of PAL test. Conclusion: These findings suggest that 5-HT4 receptor activation prevents progression of memory and cognitive impairment in a rat model of AD.Keywords: Alzheimer disease, cognition, memory, serotonin receptors
Procedia PDF Downloads 12015186 Simulations to Predict Solar Energy Potential by ERA5 Application at North Africa
Authors: U. Ali Rahoma, Nabil Esawy, Fawzia Ibrahim Moursy, A. H. Hassan, Samy A. Khalil, Ashraf S. Khamees
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The design of any solar energy conversion system requires the knowledge of solar radiation data obtained over a long period. Satellite data has been widely used to estimate solar energy where no ground observation of solar radiation is available, yet there are limitations on the temporal coverage of satellite data. Reanalysis is a “retrospective analysis” of the atmosphere parameters generated by assimilating observation data from various sources, including ground observation, satellites, ships, and aircraft observation with the output of NWP (Numerical Weather Prediction) models, to develop an exhaustive record of weather and climate parameters. The evaluation of the performance of reanalysis datasets (ERA-5) for North Africa against high-quality surface measured data was performed using statistical analysis. The estimation of global solar radiation (GSR) distribution over six different selected locations in North Africa during ten years from the period time 2011 to 2020. The root means square error (RMSE), mean bias error (MBE) and mean absolute error (MAE) of reanalysis data of solar radiation range from 0.079 to 0.222, 0.0145 to 0.198, and 0.055 to 0.178, respectively. The seasonal statistical analysis was performed to study seasonal variation of performance of datasets, which reveals the significant variation of errors in different seasons—the performance of the dataset changes by changing the temporal resolution of the data used for comparison. The monthly mean values of data show better performance, but the accuracy of data is compromised. The solar radiation data of ERA-5 is used for preliminary solar resource assessment and power estimation. The correlation coefficient (R2) varies from 0.93 to 99% for the different selected sites in North Africa in the present research. The goal of this research is to give a good representation for global solar radiation to help in solar energy application in all fields, and this can be done by using gridded data from European Centre for Medium-Range Weather Forecasts ECMWF and producing a new model to give a good result.Keywords: solar energy, solar radiation, ERA-5, potential energy
Procedia PDF Downloads 19915185 Comparison of the Logistic and the Gompertz Growth Functions Considering a Periodic Perturbation in the Model Parameters
Authors: Avan Al-Saffar, Eun-Jin Kim
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Both the logistic growth model and the gompertz growth model are used to describe growth processes. Both models driven by perturbations in different cases are investigated using information theory as a useful measure of sustainability and the variability. Specifically, we study the effect of different oscillatory modulations in the system's parameters on the evolution of the system and Probability Density Function (PDF). We show the maintenance of the initial conditions for a long time. We offer Fisher information analysis in positive and/or negative feedback and explain its implications for the sustainability of population dynamics. We also display a finite amplitude solution due to the purely fluctuating growth rate whereas the periodic fluctuations in negative feedback can lead to break down the system's self-regulation with an exponentially growing solution. In the cases tested, the gompertz and logistic systems show similar behaviour in terms of information and sustainability although they develop differently in time.Keywords: dynamical systems, fisher information, probability density function (pdf), sustainability
Procedia PDF Downloads 42615184 City Management Transformation: Urban Renewal Empowered by Chinese City Culture in the New Era
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China's urbanization rate has exceeded 60%, and in the long term, China's urbanization development will enter a new stage of transformation and development focusing on quality improvement, and urban renewal has become an important part of China's urban development. In the past, many cities in the process of renewal in order to maximize the pursuit of economic interests, large-scale demolition of the old to build new, accelerating the disappearance of regional history and culture, aggravating the homogenization of the city. With the changes in the economic and social development environment, urban renewal requires a more comprehensive perspective of action. Starting from the perspective of the core of urban management theory, this paper is oriented to culture-enabled urban renewal and takes the urban renewal of Changbin Road Area in Yuzhong District of Chongqing as an example to expound the problems and renewal strategies in its urban renewal, so as to provide references for the urban renewal of other Chinese cities in the new period.Keywords: Urban management, Urban culture, Urban renewal in mountainous areas, urban renewal
Procedia PDF Downloads 8715183 Assessing Level of Pregnancy Rate and Milk Yield in Indian Murrah Buffaloes
Authors: V. Jamuna, A. K. Chakravarty, C. S. Patil, Vijay Kumar, M. A. Mir, Rakesh Kumar
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Intense selection of buffaloes for milk production at organized herds of the country without giving due attention to fertility traits viz. pregnancy rate has lead to deterioration in their performances. Aim of study is to develop an optimum model for predicting pregnancy rate and to assess the level of pregnancy rate with respect to milk production Murrah buffaloes. Data pertaining to 1224 lactation records of Murrah buffaloes spread over a period 21 years were analyzed and it was observed that pregnancy rate depicted negative phenotypic association with lactation milk yield (-0.08 ± 0.04). For developing optimum model for pregnancy rate in Murrah buffaloes seven simple and multiple regression models were developed. Among the seven models, model II having only Service period as an independent reproduction variable, was found to be the best prediction model, based on the four statistical criterions (high coefficient of determination (R 2), low mean sum of squares due to error (MSSe), conceptual predictive (CP) value, and Bayesian information criterion (BIC). For standardizing the level of fertility with milk production, pregnancy rate was classified into seven classes with the increment of 10% in all parities, life time and their corresponding average pregnancy rate in relation to the average lactation milk yield (MY).It was observed that to achieve around 2000 kg MY which can be considered optimum for Indian Murrah buffaloes, level of pregnancy rate should be in between 30-50%.Keywords: life time, pregnancy rate, production, service period, standardization
Procedia PDF Downloads 62615182 Optimal Hybrid Linear and Nonlinear Control for a Quadcopter Drone
Authors: Xinhuang Wu, Yousef Sardahi
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A hybrid and optimal multi-loop control structure combining linear and nonlinear control algorithms are introduced in this paper to regulate the position of a quadcopter unmanned aerial vehicle (UAV) driven by four brushless DC motors. To this end, a nonlinear mathematical model of the UAV is derived and then linearized around one of its operating points. Using the nonlinear version of the model, a sliding mode control is used to derive the control laws of the motor thrust forces required to drive the UAV to a certain position. The linear model is used to design two controllers, XG-controller and YG-controller, responsible for calculating the required roll and pitch to maneuver the vehicle to the desired X and Y position. Three attitude controllers are designed to calculate the desired angular rates of rotors, assuming that the Euler angles are minimal. After that, a many-objective optimization problem involving 20 design parameters and ten objective functions is formulated and solved by HypE (Hypervolume estimation algorithm), one of the widely used many-objective optimization algorithms approaches. Both stability and performance constraints are imposed on the optimization problem. The optimization results in terms of Pareto sets and fronts are obtained and show that some of the design objectives are competing. That is, when one objective goes down, the other goes up. Also, Numerical simulations conducted on the nonlinear UAV model show that the proposed optimization method is quite effective.Keywords: optimal control, many-objective optimization, sliding mode control, linear control, cascade controllers, UAV, drones
Procedia PDF Downloads 6415181 Nonlinear Analysis of Steel Fiber Reinforced Concrete Frames Considering Shear Behaviour of Members under Varying Axial Load
Authors: Habib Akbarzadeh Bengar, Mohammad Asadi Kiadehi, Ali Rameeh
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The result of the past earthquakes has shown that insufficient amount of stirrups and brittle behavior of concrete lead to the shear and flexural failure in reinforced concrete (RC) members. In this paper, an analytical model proposed to predict the nonlinear behavior of RC and SFRC elements and frames. In this model, some important parameter such as shear effect, varying axial load, and longitudinal bar buckling are considered. The results of analytical model were verified with experimental tests. The results of verification have shown that the proposed analytical model can predict the nonlinear behavior of RC and SFRC members and also frames accurately. In addition, the results have shown that use of steel fibers increased bearing capacity and ductility of RC frame. Due to this enhancement in shear strength and ductility, insufficient amount of stirrups, which resulted in shear failure, can be offset with usage of the steel fibers. In addition to the steps taken, to analyze the effects of fibers percentages on the bearing capacity and ductility of frames parametric studies have been performed to investigate of these effects.Keywords: nonlinear analysis, SFRC frame, shear failure, varying an axial load
Procedia PDF Downloads 20615180 The Soviet Union-Style of Urban Planning in China: Historical Review and Enlightenment from the Output Mode of Contemporary Cooperative Parks
Authors: Yifeng Shi, Xingping Wang
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The Soviet Union-style of urban planning has produced a broad and profound influence on China’s urban planning system. The study on extendibility and development experience of Soviet planning in China helps to change the current embarrassing situation 'one-hand planning practice, second-hand planning theory', and also beneficial to facilitate the establishment of China's domestic urban planning theory from the planning source, especially the overseas cooperation parks rich in 'Chinese characteristics'. In practice, as the world’s major infrastructure country, China is exporting to the world especially countries along 'the Belt and Road' a development model featuring cooperation parks as Chinese characteristics. This is of great significance to evaluate and summarize the experiences of Soviet Union-style of planning for China's development objectively and rationally, from removing ideological factors and extracting positive factors to carry them forward in overseas cooperation parks. This article briefly reviews the Soviet influence on urban planning after the founding of China and divided the influences stages into 'guidance, internalization and absorption, selective learning, decline' four periods. The impact includes production-oriented planning and planning concepts continue to be implemented, the establishment of the regional planning, master planning, detailed planning of the basic framework of urban planning, and homogenized cellular structure of the space, as well as planning techniques, professional training, planning techniques and so on. China and even most socialist countries now still carry such planning genes. At present, in the process of implementing 'the Belt and Road' strategy, the planning and construction of China’s overseas cooperation parks generally encounter many problems as lack of strategic planning and systematic planning, lack of top-level design, uncoordinated planning and layout in parks, and redundant construction in some areas. After sublating the planning genes of the Soviet Union-style of urban planning for the development of the socialist countries, especially the industrial planning system, this paper puts forward some views as follows to realize the overseas output and development of China's planning model and technology. Firstly the future development of overseas cooperation park should be from a rational planning point of view. Secondly the government should not only rigidly and equitably allocate the resources of the parks but also closely integrate the national economic plans or economic development strategies. Lastly management department should frame the threshold of development rationally, give full play to the pragmatic planning style in accordance with the local land system and planning system. It has an important guiding and reference role for the development of China's overseas cooperation park under the 'go global' strategy, after objectively evaluating the impact of the Soviet Union-style urban planning and absorbing the beneficial components on China. However, we should also recognize that the cooperation parks and the urban industrial system behind it are only part of urban development. More attention should be payed on the design of the local and the general rules of urban development to take the lead effect of cooperation parks suitable. Foundation item: Under the auspices of the Specific Plan for Strategic International Cooperation in Scientific and Technological Innovation, the National Key Research and Development Plan 'Research Cooperation and Exemplary Application in Planning of Development of Overseas Industrial Parks' (No 2016YFE0201000).Keywords: China cooperative parks, history of urban planning, output mode, The Soviet Union
Procedia PDF Downloads 24115179 Nonlinear Aerodynamic Parameter Estimation of a Supersonic Air to Air Missile by Using Artificial Neural Networks
Authors: Tugba Bayoglu
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Aerodynamic parameter estimation is very crucial in missile design phase, since accurate high fidelity aerodynamic model is required for designing high performance and robust control system, developing high fidelity flight simulations and verification of computational and wind tunnel test results. However, in literature, there is not enough missile aerodynamic parameter identification study for three main reasons: (1) most air to air missiles cannot fly with constant speed, (2) missile flight test number and flight duration are much less than that of fixed wing aircraft, (3) variation of the missile aerodynamic parameters with respect to Mach number is higher than that of fixed wing aircraft. In addition to these challenges, identification of aerodynamic parameters for high wind angles by using classical estimation techniques brings another difficulty in the estimation process. The reason for this, most of the estimation techniques require employing polynomials or splines to model the behavior of the aerodynamics. However, for the missiles with a large variation of aerodynamic parameters with respect to flight variables, the order of the proposed model increases, which brings computational burden and complexity. Therefore, in this study, it is aimed to solve nonlinear aerodynamic parameter identification problem for a supersonic air to air missile by using Artificial Neural Networks. The method proposed will be tested by using simulated data which will be generated with a six degree of freedom missile model, involving a nonlinear aerodynamic database. The data will be corrupted by adding noise to the measurement model. Then, by using the flight variables and measurements, the parameters will be estimated. Finally, the prediction accuracy will be investigated.Keywords: air to air missile, artificial neural networks, open loop simulation, parameter identification
Procedia PDF Downloads 26315178 The Importance of Downstream Supply Chain in Supply Chain Risk Management: Multi-Objective Optimization
Authors: Zohreh Khojasteh-Ghamari, Takashi Irohara
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One of the efficient ways in supply chain risk management is avoiding the interruption in Supply Chain (SC) before it occurs. Although the majority of the organizations focus on their first-tier suppliers to avoid risk in the SC, studies show that in only 60 percent of the disruption cases the reason is first tier suppliers. In the 40 percent of the SC disruptions, the reason is downstream SC, which is the second tier and lower. Due to the increasing complexity and interrelation of modern supply chains, the SC elements have become difficult to trace. Moreover, studies show that there is a vital need to better understand the integration of risk and visibility, especially in the context of multiple objectives. In this study, we propose a multi-objective programming model to avoid disruption in SC. The objective of this study is evaluating the effect of downstream SCV on managing supply chain risk. We propose a multi-objective mathematical programming model with the objective functions of minimizing the total cost and maximizing the downstream supply chain visibility (SCV). The decision variable is supplier selection. We assume there are several manufacturers and several candidate suppliers. For each manufacturer, our model proposes the best suppliers with the lowest cost and maximum visibility in downstream supply chain. We examine the applicability of the model by numerical examples. We also define several scenarios for datasets and observe the tendency. The results show that minimum visibility in downstream SC is needed to have a safe SC network.Keywords: downstream supply chain, optimization, supply chain risk, supply chain visibility
Procedia PDF Downloads 23815177 Create a Brand Value Assessment Model to Choosing a Cosmetic Brand in Tehran Combining DEMATEL Techniques and Multi-Stage ANFIS
Authors: Hamed Saremi, Suzan Taghavy, Seyed Mohammad Hanif Sanjari, Mostafa Kahali
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One of the challenges in manufacturing and service companies to provide a product or service is recognized Brand to consumers in target markets. They provide most of their processes under the same capacity. But the constant threat of devastating internal and external resources to prevent a rise Brands and more companies are recognizing the stages are bankrupt. This paper has tried to identify and analyze effective indicators of brand equity and focuses on indicators and presents a model of intelligent create a model to prevent possible damage. In this study, the identified indicators of brand equity are based on literature study and according to expert opinions, set of indicators By techniques DEMATEL Then to used Multi-Step Adaptive Neural-Fuzzy Inference system (ANFIS) to design a multi-stage intelligent system for assessment of brand equity.Keywords: brand, cosmetic product, ANFIS, DEMATEL
Procedia PDF Downloads 40915176 A Simplified Distribution for Nonlinear Seas
Authors: M. A. Tayfun, M. A. Alkhalidi
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The exact theoretical expression describing the probability distribution of nonlinear sea-surface elevations derived from the second-order narrowband model has a cumbersome form that requires numerical computations, not well-disposed to theoretical or practical applications. Here, the same narrowband model is re-examined to develop a simpler closed-form approximation suitable for theoretical and practical applications. The salient features of the approximate form are explored, and its relative validity is verified with comparisons to other readily available approximations, and oceanic data.Keywords: ocean waves, probability distributions, second-order nonlinearities, skewness coefficient, wave steepness
Procedia PDF Downloads 42615175 Improving Human Hand Localization in Indoor Environment by Using Frequency Domain Analysis
Authors: Wipassorn Vinicchayakul, Pichaya Supanakoon, Sathaporn Promwong
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A human’s hand localization is revised by using radar cross section (RCS) measurements with a minimum root mean square (RMS) error matching algorithm on a touchless keypad mock-up model. RCS and frequency transfer function measurements are carried out in an indoor environment on the frequency ranged from 3.0 to 11.0 GHz to cover federal communications commission (FCC) standards. The touchless keypad model is tested in two different distances between the hand and the keypad. The initial distance of 19.50 cm is identical to the heights of transmitting (Tx) and receiving (Rx) antennas, while the second distance is 29.50 cm from the keypad. Moreover, the effects of Rx angles relative to the hand of human factor are considered. The RCS input parameters are compared with power loss parameters at each frequency. From the results, the performance of the RCS input parameters with the second distance, 29.50 cm at 3 GHz is better than the others.Keywords: radar cross section, fingerprint-based localization, minimum root mean square (RMS) error matching algorithm, touchless keypad model
Procedia PDF Downloads 33415174 Multiscale Analysis of Shale Heterogeneity in Silurian Longmaxi Formation from South China
Authors: Xianglu Tang, Zhenxue Jiang, Zhuo Li
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Characterization of shale multi scale heterogeneity is an important part to evaluate size and space distribution of shale gas reservoirs in sedimentary basins. The origin of shale heterogeneity has always been a hot research topic for it determines shale micro characteristics description and macro quality reservoir prediction. Shale multi scale heterogeneity was discussed based on thin section observation, FIB-SEM, QEMSCAN, TOC, XRD, mercury intrusion porosimetry (MIP), and nitrogen adsorption analysis from 30 core samples in Silurian Longmaxi formation. Results show that shale heterogeneity can be characterized by pore structure and mineral composition. The heterogeneity of shale pore is showed by different size pores at nm-μm scale. Macropores (pore diameter > 50 nm) have a large percentage of pore volume than mesopores (pore diameter between 2~ 50 nm) and micropores (pore diameter < 2nm). However, they have a low specific surface area than mesopores and micropores. Fractal dimensions of the pores from nitrogen adsorption data are higher than 2.7, what are higher than 2.8 from MIP data, showing extremely complex pore structure. This complexity in pore structure is mainly due to the organic matter and clay minerals with complex pore network structures, and diagenesis makes it more complicated. The heterogeneity of shale minerals is showed by mineral grains, lamina, and different lithology at nm-km scale under the continuous changing horizon. Through analyzing the change of mineral composition at each scale, random arrangement of mineral equal proportion, seasonal climate changes, large changes of sedimentary environment, and provenance supply are considered to be the main reasons that cause shale minerals heterogeneity from microcosmic to macroscopic. Due to scale effect, the change of shale multi scale heterogeneity is a discontinuous process, and there is a transformation boundary between homogeneous and in homogeneous. Therefore, a shale multi scale heterogeneity changing model is established by defining four types of homogeneous unit at different scales, which can be used to guide the prediction of shale gas distribution from micro scale to macro scale.Keywords: heterogeneity, homogeneous unit, multiscale, shale
Procedia PDF Downloads 441