Articoli di riviste: "Solar simulation and experimentation"

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Ghabuzyan, Levon, Kevin Pan, Arianna Fatahi, Jim Kuo e Christopher Baldus-Jeursen. "Thermal Effects on Photovoltaic Array Performance: Experimentation, Modeling, and Simulation". Applied Sciences 11, n. 4 (5 febbraio 2021): 1460. http://dx.doi.org/10.3390/app11041460.

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The performance of photovoltaic (PV) arrays are affected by the operating temperature, which is influenced by thermal losses to the ambient environment. The factors affecting thermal losses include wind speed, wind direction, and ambient temperature. The purpose of this work is to analyze how the aforementioned factors affect array efficiency, temperature, and heat transfer coefficient/thermal loss factor. Data on ambient and array temperatures, wind speed and direction, solar irradiance, and electrical output were collected from a PV array mounted on a CanmetENERGY facility in Varennes, Canada, and analyzed. The results were compared with computational fluid dynamics (CFD) simulations and existing results from PVsyst. The findings can be summarized into three points. First, ambient temperature and wind speed are important factors in determining PV performance, while wind direction seems to play a minor role. Second, CFD simulations found that temperature variation on the PV array surface is greater at lower wind speeds, and decreases at higher wind speeds. Lastly, an empirical correlation of heat transfer coefficient/thermal loss factor has been developed.

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Kareem, M. W., Khairul Habib e S. I. Gilani. "Lumped Components Modeling of Double Pass Solar Collector with Porous Matrixes". Applied Mechanics and Materials 465-466 (dicembre 2013): 216–20. http://dx.doi.org/10.4028/www.scientific.net/amm.465-466.216.

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In this report, the modeling and simulation of a double pass solar air absorber was carried out using combination of Simscape and Simulink modeling tools. The solar system air mass flow rate and the porous media were critically investigated by using local weather data of Seri Iskandar, Perak, Malaysia. Optimal inlet air flow rate of 0.034kgm-2s-1 was obtained and one of the packed beds, sandstone extended the thermal transfer period of solar collector system by 1150s which displayed good agreement with the reported model and experimental outcomes. The results obtained have shown that it is a promising alternative tool for solar thermal experimentation modeling.

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Suresh Babu, G., B. Prem Charan e T. Murali Krishna. "Performance Analysis of SPV Module Using Solar PVTR System". International Journal of Engineering & Technology 7, n. 3.3 (21 giugno 2018): 68. http://dx.doi.org/10.14419/ijet.v7i3.3.14488.

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With a spurt in the use of non-conventional energy sources, photovoltaic installations are being deployed in several applications such as distributed power generation and standalone systems. Solar Photo Voltaic (SPV) module is the basic component of the solar PV system. The functioning of a photovoltaic array is influenced by solar insolation, shading and array arrangement. Often the PV arrays get shadowed, completely or partially by neighboring buildings, trees, towers and service poles. The efficacy of PV array unvaryingly depends upon temperature which in turn is reliant on radiation. In order to validate this hypothesis, there are certain instruments and experimentation methods available which are expensive. But carrying out hardware testing on the solar PV system with Photo Voltaic Training and Research (PVTR) system and simulating using software will lead to least economical method of achieving performance analysis which is the main objective of this paper. The efficiency of PV module is analyzed from I-V and P-V characteristics for this standalone solar pv system by changing radiation and temperature parameters. This paper mainly emphases on comparison of the testing results and simulation results for different radiation levels.

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T R, Mohan Kumar, P. V. Srihari e M. S. Krupashankara. "Simulation and Optimization of Coating thickness for Absorptance and Reflectance in Multilayered Thin Films". International Journal of ChemTech Research 13, n. 4 (2020): 364–73. http://dx.doi.org/10.20902/ijctr.2019.130405.

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Solar selective materials and structure of solar thermal energy conversion systems plays a prominent role for the improvement of optical properties. In the present work simulations on multi-layered thin films have been conducted using code software with Mo and Was functional layer in combination with bond layer and protective layers of Si3N4 and Al2O3. The better combination is selected for optimization on thickness for absorption and reflection. To simplify experimentation, Taguchi‟s design of experiments approach was adopted to determine the optimum material layer combination.The results indicate for multi-layered thin films that combination of Al2O3-Mo-Al2O3 has better reflectance of 50.48% and combination Si3N4-W-Si3N4 has better absorptance of 74.81% upon optimization on thickness of bond layers, functional and protective layers. These results are discussed on main effect plots, contour plots and surface plots.

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Chenchireddy, Kalagotla, Khammampati R. Sreejyothi, Podishetti Ganesh, Gatla Uday Kiran, Chilukuri Shiva e Banoth Nithish Kumar. "Fundamental frequency switching strategies of a seven level hybrid cascaded H-bridge multilevel inverter". International Journal of Applied Power Engineering (IJAPE) 13, n. 2 (1 giugno 2024): 263. http://dx.doi.org/10.11591/ijape.v13.i2.pp263-268.

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This paper presents a novel hybrid cascaded H-bridge multilevel inverter (HCHB MLI) designed to address the growing importance of multilevel inverters in the context of renewable energy sources such as solar, wind, and fuel cells. The proposed topology features eight insulated-gate bipolar transistor (IGBT) switches and utilizes two distinct input direct current (DC) sources: a battery and a capacitor, making it a hybrid system. The control strategy employed in this topology is based on fundamental switching frequency techniques. Simulation results of the proposed topology are conducted using MATLAB/Simulink software, while hardware experimentation with a single-phase H-bridge inverter is also demonstrated in the paper. For pulse generation and IGBT switch control, an Arduino UNO microcontroller is utilized. The output voltage of the single-phase H-bridge inverter is verified through experimentation using a cathode-ray oscilloscope (CRO).

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Ordaz Castillo, Job, Hector D. Garcia-Lara, Nilda Gabriela Trejo-Luna e Santos Mendez-Diaz. "An open-loop control algorithm for improved tracking in a heliostat". Renewable energy, biomass & sustainability 6, n. 1 (11 aprile 2024): 50–56. http://dx.doi.org/10.56845/rebs.v6i1.90.

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The growing energy demand and its relation to climate change have driven the search for sustainable alternatives, such as concentrated solar energy. In this context, heliostats play a crucial role by reflecting and concentrating solar light onto a receiver. However, traditional control approaches based on geographical data have limitations. This study introduces an autonomous control system for heliostats that eliminates the need for preloaded geographical data. The approach is based on communication between the heliostat and the solar tracker, with two configuration modes: map calibration and automatic. Centralized and autonomous heliostats are distinguished, with the latter being the focus of the study. Autonomous heliostats have their own control system and can make decisions regarding positioning and safety. The methodology involves a mathematical algorithm that calculates the optimal rotation and tilt of the heliostat to redirect light toward a target. Simulation and physical prototype testing validate a remarkable consistency between simulated and experimental data. A key result is the surprising similarity of 97.9% between the obtained data, validating the algorithm's effectiveness. This study provides a robust approach for designing autonomous heliostat control systems, integrating simulation and experimentation. These results support the algorithm's precision and ability to direct solar radiation effectively. Expanding towards autonomous control and complete heliostat system evaluation facilitates the path toward more efficient and sustainable concentrated solar energy.

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Harmim, A., M. Boukar, M. Amar e Aek Haida. "Simulation and experimentation of an integrated collector storage solar water heater designed for integration into building facade". Energy 166 (gennaio 2019): 59–71. http://dx.doi.org/10.1016/j.energy.2018.10.069.

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Ouédraogo, Salifou, Thierry S. M. Ky, Amadou Konfé, Sié Kam e D. Joseph Bathiébo. "Expérimentation et analyse thermique d’un concentrateur hémisphérique stationnaire sous les conditions climatiques à Ouagadougou, Burkina Faso". Journal de Physique de la SOAPHYS 2, n. 1b (5 marzo 2021): C20A04–1—C20A04–1. http://dx.doi.org/10.46411/jpsoaphys.2020.01.04.

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This technology is used in drying, domestic water heating or in the production of electricity. However, it uses a solar tracking system that is too complex and expensive for countries with less equipment and high solar potential. In this study, we are interested in the experimentation and thermal analysis of a stationary hemispheric concentrator. The numerical resolution of the caustic equations of a spherical concentrator allowed to determine the dimensions and the position of the receiver, necessary for the design of the physical model and the assembly of the experimental device. The results of the 3D numerical simulation with the Comsol5.3a software allowed to highlight the ray tracing and the profile of the flow concentrated on the receiver. The results obtained experimentally show that the receiver and the air inside reached a maximum temperature of 224°C and 97.6°C respectively. The solar concentration device studied is therefore technically favorable for thermal applications requiring intermediate temperatures.

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Reveles-Miranda, María, Diego Sánchez-Flórez, José Cruz-Chan, Eduardo Ordoñez-López, Manuel Flota-Bañuelos e Daniella Pacheco-Catalán. "The Control Scheme of the Multifunction Inverter for Power Factor Improvement". Energies 11, n. 7 (26 giugno 2018): 1662. http://dx.doi.org/10.3390/en11071662.

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Grid-connected photovoltaic (PV) systems require an inverter that allows an efficient integration between the panels and the grid; however, the operation of conventional inverters is limited to the periods of power generation by the panels. This paper proposes a control scheme based on the theory of passivity to provide additional functions to the inverter of a PV system. These additional functions improve the power quality; for example, when loads demand inductive currents be connected, the power factor is improved independently of the intermittency of the solar energy source. The performance of the system with the passivity-based control is verified by simulation and experimentation using MATLAB/Simulink® (2017a, MathWorks, Natick, MA, USA).

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Gokhale, Hrishikesh, e Lochan Chaudhari. "Eco-Friendly and Renewable Power Generation from Heat Using Thermophotovoltaic Technology". ECS Transactions 107, n. 1 (24 aprile 2022): 14641–54. http://dx.doi.org/10.1149/10701.14641ecst.

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Renewable energy sources are the need of the hour, considering climate change’s impact on our planet. Many sources are currently being researched, none of them are commercially stable enough to compete with the existing non-renewable energy sources, with the main reason being performance for the price. We aim to develop a practical system based on the current research progress in infrared-based thermophotovoltaic power generation and storage. Similar systems already exist for harnessing solar energy, but we plan to overcome the inability of solar energy to produce electricity in the absence of sunlight by developing an infrared-based system. Another challenge is the unavailability of enough thermal radiation in the vicinity to support the system from different sources. The main objectives of this work are to identify the advantages and disadvantages of such a system, its feasibility, and its efficiency for working in the real world through theoretical predictions, simulation, and experimentation.

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Ramaprabha, R., K. Balaji, SB Raj e VD Logeshwaran. "Comparison of Interleaved Boost Converter Configurations for Solar Photovoltaic System Interface". Journal of Engineering Research [TJER] 10, n. 2 (1 dicembre 2013): 87. http://dx.doi.org/10.24200/tjer.vol10iss2pp87-98.

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Solar photovoltaic (SPV) panels that convert light energy into electrical energy through the photovoltaic effect have nonlinear internal resistance. Hence, with the variation in the intensity of light falling on the panel, the internal resistance varies. For effective utilization of the SPV panel, it is necessary to extract the maximum power from it. For maximum power extraction from SPV panels, DC-DC converter interface is used. The problem in using high frequency converter interface is the resultant high frequency ripple interaction with the SPV system. In this work, an interleaved boost converter (IBC) is considered to reduce the ripple. Our finding is that IBC fed by a SPV panel reduces this ripple to a greater extent. IBC also has a faster transient response as compared to conventional boost converters with reduced ripple contents. The main aim of this paper is to present a comparative analysis of the performance of IBC with inductors that are coupled in different ways. The results of the simulation were extrapolated with the help of MATLAB software and verified through experimentation.

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Chan, Kwing L., e Katsuyo Serizawa. "On Numerical Studies of Solar/Stellar Convection". International Astronomical Union Colloquium 130 (1991): 15–26. http://dx.doi.org/10.1017/s0252921100079343.

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It has become a cliché to say that convection lies at the foundation of the activities, magnetism, and dynamos of the Sun and cool stars – the title of this colloquium. However, it has not been possible, until recently, to study theoretically these phenomena and their connections with quantitative rigor. The new development owes much to the rapid growth in the power of computers and the spread of sophisticated numerical techniques.Since the last decade numerical studies of solar and stellar convection problems thrive. The trend towards a greater use of computers in these studies will likely become stronger. Now is a good time to reflect on the numerical approach itself, so that we may understand it better and make better use of it in the future. Here we look at two aspects of this methodology. First (Section 2), we examine its relationships to the analytical approach and observation, for which we make a differentiation between numerical experimentation and simulation. It is obvious that the ultimate test of any theory, numerical or not, is to confront observations, but not generally realized is that the connection to analytical studies is an important requisite for the healthy development of numerical studies. This point is to be elaborated. Second (Section 3), we discuss the prevalence of pitfalls in the numerical approach; two examples of current interest in convection computations are analysed in detail. In Section 4, we go on to suggest that one of these pitfalls might have caused the discrepancy between the results of numerical modelling of the solar differential rotation and helioseismology.

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Ratsimbazafiharivola, Jaurès, e H. T. Rakotondramiarana. "Study of the Thermal Comfort of a Building that does not Comply with Construction Standards in Madagascar: Experimentation and Simulation with OMEdit". European Journal of Engineering Research and Science 4, n. 4 (28 aprile 2019): 124–30. http://dx.doi.org/10.24018/ejers.2019.4.4.1235.

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A very large number of buildings in developing countries are far from complying with the standards of housing. This paper presents the subjective study of the thermal comfort of a building that does not comply with construction standards or thermal regulations, located in Madagascar. Modeling was done using the Modelica tool, especially its BuildSysPro library. In order to minimize the inaccuracies, a step of an experimental adjustment of the developed numerical model was also carried out usingexperimental reference data that were obtained from the temperaturemeasurementsof the studied building elements as well as the wind speed and the received solar radiation flux. It was found that despite the obvious non-compliance with building standards and thermal regulations, the building has an acceptable thermal environment vis-à-vis its occupant.

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Ratsimbazafiharivola, Jaurès, e H. T. Rakotondramiarana. "Study of the Thermal Comfort of a Building that does not Comply with Construction Standards in Madagascar: Experimentation and Simulation with OMEdit". European Journal of Engineering and Technology Research 4, n. 4 (28 aprile 2019): 124–30. http://dx.doi.org/10.24018/ejeng.2019.4.4.1235.

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Abstract (sommario):

A very large number of buildings in developing countries are far from complying with the standards of housing. This paper presents the subjective study of the thermal comfort of a building that does not comply with construction standards or thermal regulations, located in Madagascar. Modeling was done using the Modelica tool, especially its BuildSysPro library. In order to minimize the inaccuracies, a step of an experimental adjustment of the developed numerical model was also carried out usingexperimental reference data that were obtained from the temperaturemeasurementsof the studied building elements as well as the wind speed and the received solar radiation flux. It was found that despite the obvious non-compliance with building standards and thermal regulations, the building has an acceptable thermal environment vis-à-vis its occupant.

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Barone, G., A. Buonomano, V. Palmieri e A. Palombo. "A prototypal high-vacuum integrated collector storage solar water heater: Experimentation, design, and optimization through a new in-house 3D dynamic simulation model". Energy 238 (gennaio 2022): 122065. http://dx.doi.org/10.1016/j.energy.2021.122065.

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Wang, Yuelong, e Weiqing Wang. "Research on the Control Strategy of Urban Integrated Energy Systems Containing the Fuel Cell". Processes 11, n. 5 (22 maggio 2023): 1584. http://dx.doi.org/10.3390/pr11051584.

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High efficiency is one of the many benefits of this novel kind of energy; clean and pollution free fuel cells have attracted the attention of many experts and scholars. The efficient use of fuel cells will certainly become the mainstay of energy transformation and environmental protection. However, fuel cells have low power density, soft electrical output characteristics, and significantly delayed response to sudden load changes. When fuel cells are used as power supply energy alone, the output voltage fluctuates greatly, and the power supply reliability could be higher. To increase the fuel cell’s service life in real world applications, a DC converter and an appropriate auxiliary energy storage power supply are combined to form a fuel cell hybrid power supply system that makes efficient use of the auxiliary energy storage system’s availability, enhances the power supply system’s adaptability through dynamic reconfiguration, and provides better flexibility overall. This work proposes a method for managing the energy produced by an urban integrated power supply system that includes fuel cells, supercapacitors, and solar cells. Applying the IF-THEN rule of load power and the state of charge of the supercapacitors, the power balance is adjusted between the su-percapacitors, photovoltaic cells, and fuel cells according to the defined fuzzy logic control. The intermittent nature of solar power production and the erratic nature of fuel cell output may both be mitigated using this technique, allowing the load power to operate more reliably. The simulation results show that the control strategy adopted in this paper is able to not only meet the load requirements but also reasonably allocate the functional requirements and improve the working efficiency of the system, resulting in a clear optimization effect on the system’s control. In this paper, we focus on the fuel cell hybrid power supply system design, and then we use the idea of fuzzy logic control energy management to build the structure of the fuzzy logic control system, design the fuzzy controller, determine the functions, and verify the solutions through simulation and experimentation.

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Yoo, Seung-Ho. "Thermal Behavior of Passive Intelligent Radiant Cooling Systems". Processes 10, n. 12 (12 dicembre 2022): 2666. http://dx.doi.org/10.3390/pr10122666.

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Efficient cooling and heating solutions for nearly zero-energy solar dwellings are required to mitigate climate change and to make dwellings sustainable. The installed pipeline for a radiant heating system, which is only used for space heating when heating is necessary, can also be used to cool the room with only the enthalpic use of natural city water by releasing the natural city water through the embedded pipeline already installed for radiant heating. Natural city water used for radiant cooling can be used in necessary locations such as for toilets, washing cars, laundry facilities, and garden water, which corresponds to approximately 56% of the water we use at home. As a result, the embedded pipes that make up a radiant heating system can be converted to a passive intelligent radiant cooling system with minimal added installation and control systems. Thermal comfort and behavior analyses in an enclosure with a radiant cooling system are fulfilled through experimentation, mean radiant temperature simulation, and asymmetric radiation calculation. No uncomfortable asymmetric radiation is encountered during the cooling period, so the cooling spaces are well controlled within the comfortable cooling range. A passive intelligent radiant cooling system that uses just the enthalpy of natural city water can be an appropriate ecological solution to better develop zero-energy dwellings. No extra cooling energy and power are required to cool a space that uses just enthalpy and pressure from natural city water.

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Alshomrany, Ali S., J. Fatima Rasheed, Thamraa Alshahrani, Firoz Khan, Syed Kashif Ali e Mohd Taukeer Khan. "Investigating the influence of the Ag and Al co-doping in ZnO electron transport layer on the performance of organic-inorganic perovskite solar cells using experimentation and SCAPS-1D simulation". Optical Materials 157 (novembre 2024): 116173. http://dx.doi.org/10.1016/j.optmat.2024.116173.

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Ebolese, Amedeo, Domenico Marano, Carlo Copeta, Agatino Bruno e Vincenzo Sabatelli. "Numerical Modeling and Experimental Validation of Heat Transfer Characteristics in Small PTCs with Nonevacuated Receivers". Solar 3, n. 4 (12 ottobre 2023): 544–65. http://dx.doi.org/10.3390/solar3040030.

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The development of small-sized parabolic trough collectors (PTCs) for processing heat production at medium temperatures (100–250 °C) represents an interesting approach to increase the utilization of solar thermal technologies in industrial applications. Thus, the development of simplified models to analyze and predict their performance under different operative and climatic conditions is crucial for evaluating the application potential of this low-cost technology. In this paper, we present a numerical method that by combining three-dimensional finite element simulations (implemented with COMSOL Multiphysics software version 6.1) with a one-dimensional analysis (based on a MATLAB script) allows for the theoretical determination of the power output of a small-PTC with a nonevacuated tubular receiver operating at a medium temperature. The finite element model considers both the nonuniformity of the concentrated solar flux on the receiver tube (evaluated using Monte Carlo ray-tracing analysis) and the establishment of natural convection in the air gap between the glass envelope and absorber tube. The model calculates, for several values of direct normal irradiance (DNI) and inlet temperatures, the thermal power transferred to the heat transfer fluid (HTF) per unit length. The data are fitted using the multiple linear regression method, obtaining a function that is then used in a one-dimensional multi-nodal model to estimate the temperatures and the heat gains along the receiver tube. The outputs of the model are the outlet temperature and the total thermal power transferred to the HTF. In order to validate the developed methodology for the assessment of the heat transfer characteristics in the small-PTC with a nonevacuated receiver, an experiment at the ENEA Trisaia—Solar Thermal Collector Testing Laboratory was carried out. This work compares the theoretical data with those acquired through experimentation, obtaining a good agreement, with maximum differences of 0.2% and 3.6% for the outlet temperatures and the power outputs, respectively.

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Lakshmipathy, B., K. Sivakumar, M. Senthilkumar, A. Kajavali, S. Christopher Ezhil Singh e Sivaraj Murugan. "Performance Characterization of a Solar Cavity Collector Using Artificial Neural Network". Modelling and Simulation in Engineering 2022 (23 marzo 2022): 1–9. http://dx.doi.org/10.1155/2022/7129833.

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It is mandatory to improve the design of the flat plate collector (FPC) used for solar thermal applications to perform well. One way to improve the performance characteristics of FPC is to retain the heat energy available inside the collector. That is, a collector should be capable to give more heat energy to working fluid for a longer duration. It has been implemented in such a way in an entertained and improved model which is known as solar cavity collector (SCC). It consists of 5 numbers of cavities equipped with inlet and outlet tubes. The same having with an enclosure has been constructed and investigated to find the optimal performance. In general, the physical dimensions of the collector influence more the functioning behaviors of SCC. The performance variables that are considered for the present study are the comparison between 5 and 7 numbers of cavities and the effect of aperture entry. Collector angle of tilt, two types of flow mode, and water mass flow rates are the other performance variables that are also considered. The data from the experimentations are trained, tested, and validated with the help of the artificial neural network (ANN). The accuracy of the model is 96%, and the end results revealed the same trend followed by both experimental and ANN simulation results. Also, the variations that occur between ANN and experimented results are ±4%.

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Covey, Curt, Aiguo Dai, Richard S. Lindzen e Daniel R. Marsh. "Atmospheric Tides in the Latest Generation of Climate Models*". Journal of the Atmospheric Sciences 71, n. 6 (30 maggio 2014): 1905–13. http://dx.doi.org/10.1175/jas-d-13-0358.1.

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Abstract For atmospheric tides driven by solar heating, the database of climate model output used in the most recent assessment report of the Intergovernmental Panel on Climate Change (IPCC) confirms and extends the authors’ earlier results based on the previous generation of models. Both the present study and the earlier one examine the surface pressure signature of the tides, but the new database removes a shortcoming of the earlier study in which model simulations were not strictly comparable to observations. The present study confirms an approximate consistency among observations and all model simulations, despite variation of model tops from 31 to 144 km. On its face, this result is surprising because the dominant (semidiurnal) component of the tides is forced mostly by ozone heating around 30–70-km altitude. Classical linear tide calculations and occasional numerical experimentation have long suggested that models with low tops achieve some consistency with observations by means of compensating errors, with wave reflection from the model top making up for reduced ozone forcing. Future work with the new database may confirm this hypothesis by additional classical calculations and analyses of the ozone heating profiles and wave reflection in Coupled Model Intercomparison Project (CMIP) models. The new generation of models also extends CMIP's purview to free-atmosphere fields including the middle atmosphere and above.

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Assem, Houria, Toufik Azib, Farid Bouchafaa, Cherif Laarouci, Nasreddine Belhaouas e Amar Hadj Arab. "Adaptive Fuzzy Logic-Based Control and Management of Photovoltaic Systems with Battery Storage". International Transactions on Electrical Energy Systems 2023 (23 maggio 2023): 1–18. http://dx.doi.org/10.1155/2023/9065061.

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Renewable energy sources (RESs) such as solar photovoltaic (PV) systems are increasingly used as distributed generation for replacing the conventional energy. At the same time, energy storage systems like battery (BAT) must be applied for maintaining the balance between fluctuating energy production and load consumption. BAT’s state of charge (SOC) should be maintained within their design limits unaffected by RES intermittency and/or load power variations. This necessitates advanced power control and management methodologies for overcoming challenging conditions. This paper discusses and evaluates an optimal DC bus voltage regulation approach: an intelligent controller using an adaptive fuzzy logic controller (FLC) and a novel supervisory power management strategy for PV systems with BAT. The objectives are to keep a stable power flow in the system and guarantee the continuity of service by ensuring that the system components do not exceed their limits. In this manner, the DC bus voltage regulation of the PV/BAT system can be improved in comparison with conventional regulation. Therefore, the most important contributions of this work are as follows. (1) Development of comprehensive and modular novel energy management system (EMS): its originality is related to the inclusion of the control system limits with faster SOC balancing and smaller DC bus voltage fluctuation. (2) Providing a simple power flow management implementation that considers the optimal energy flow between PV system, BAT system, and load: a balance between minimal energy flow in the connecting line and the least requirements of BAT capacity is kept, reducing component constraints with a very straightforward structure. (3) Furthermore, FLC offers high robustness and smooth performances. FLC is added to the control strategy design requirements to reduce DC bus voltage deviation. (4) Real-time simulation/experimentation-based complete cases utilizing Matlab/Simulink and DSpace are illustrated to testify the effectiveness of the proposed FLC and EMS.

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Sah, Nandkishor, e Mohan Jagadeesh Kumar Mandapati. "Thermal performance of a double-pass solar air heater (SAH) with ribbed absorber surface – an experimental study". World Journal of Engineering 17, n. 3 (31 marzo 2020): 373–80. http://dx.doi.org/10.1108/wje-08-2019-0217.

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Abstract (sommario):

Purpose Use of packed beds, enhanced tubes, nano-fluids and artificial ribs are few passive techniques to increase heat transfer in solar air heaters (SAHs). Artificial ribs attached to the absorber plate of the SAH will enhance the turbulence near the plate. Experimental analyses are conducted to find the thermal performance of SAH with ribs of regular geometries including rectangular, semi-circular and triangular in cross section. This paper aims to present the improvement in thermal performance of SAH with modified-arc. Design/methodology/approach Absorber plates are designed with ribs of rectangular, triangular, semi-circular and modified-arc in cross-section using existing data in literature. Physical dimensions of the ribs are designed by adapting procedure from literature. Absorber plates are manufactured with ribs and coated with blackboard paint and fixed to the existing SAH. Experiments are conducted with a variable-speed blower fixed to the inlet section of the SAH, which is used to supply air at different mass flow rates in a range between 0.495 and 0.557 kg/min. Findings Efficiency is found to be a strong function of mass flow rate of air through the SAH from the present experimental investigations. It was found that use of modified-arc ribs enhanced the efficiency of SAH by 105.35 per cent compared to SAH with plane absorber plate. Efficiency of SAH with modified-arc ribs is found to be higher by 24.43, 45.61 and 63.21 per cent, respectively, for SAH with semi-circular, rectangular and triangular arc ribs on its absorber plate. Research limitations/implications Experiments on SAH are conducted during daytime from 9:00 am to 5:00 pm in open atmospheric conditions. Solar intensity is continuously changing during the experimentation from morning to evening. Calculations are made based on the observations with average values of solar intensity and temperature readings. More accurate values of SAH efficiency can be obtained with constant heat supply to the absorber plate by simulating the experimental setup in indoor conditions. Temperature and flow rate observations could be more accurate with sophisticated instrumentation rather than using simple thermocouples and orifice meters. Social implications SAHs are basically used to supply hot air for both rural and industrial applications. These are used for crop drying, preheating of air, removal of moisture from leather, chemicals, etc. Conventionally, formers in India are using open sun drying to remove moisture from agricultural products. In this method, the moisture can be removed up to a level of 20 to 25 per cent. Use of SAH can remove moisture up to below 5 per cent and process is clean without reducing the quality of agricultural products. Enhancing the efficiency of SAHs will surely increase its usage by formers for crop drying. Originality/value Use of artificial ribs on absorber plate of SAH is most economical among many of the active and passive techniques. Numerical and experimental investigations are found in literature with regular cross-sectional ribs, including rectangular, triangular and semi-circular. The present work proposed new shape of the ribs named as modified-arc, which was not presented in the literature. Experimental analysis proved that the use of modified-arc makes the SAH more efficient in heat transfer.

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Sankar, Anjana, Kritesh Kumar Gupta e Vishal Bhalla. "Development of Data-Driven Predictive Framework for Nanofluid-based Solar Thermal Collector: A Machine Learning Approach". E3S Web of Conferences 559 (2024): 02003. http://dx.doi.org/10.1051/e3sconf/202455902003.

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The conventional approach for solar collector design often requires performing large-scale experimentations or computationally intensive simulations which hinders the comprehensive screening and optimization of process design. This creates a strong rationale for developing a computationally efficient framework capable of leveraging a relatively small number of samples to generate a machine-learning model with sufficiently high fidelity. In this regard, the present study aims to integrate the concepts of random sampling, Gaussian process(GP), and Bayesian optimization for developing a computationally efficient data-driven framework for capturing the complete continuous domain of the parametric variation and predicting the desired performance measure. The proposed framework is rigorously tested at different stages with the help of unknown samples (out-of-fold test samples) to ensure the sound generalization capability of the constructed model. The model assessment revealed that the increase in sample size for training the GP model from 35 samples to 105 samples resulted in ≈ 56% reduction in root mean square error (RMSE), which further reduces to ≈ 96.5% after performing Bayesian optimization based hyperparameter tuning. The proposed framework will be extremely helpful in designing the highly efficient nanofluid-based solar thermal collector, by preventing the need of performing large-scale experimentations/simulations for screening purpose.

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Khade, Neil. "Chemical Experimentation for Solar Pain Reliever". INTERANTIONAL JOURNAL OF SCIENTIFIC RESEARCH IN ENGINEERING AND MANAGEMENT 08, n. 05 (4 maggio 2024): 1–5. http://dx.doi.org/10.55041/ijsrem32385.

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The Solar Pain Reliever is a cutting-edge device that combines renewable energy and therapeutic relaxation. By harnessing the power of the sun, the Solar Pain Reliever utilizes small solar panels to convert sunlight into heat energy to provide gentle and comforting heat therapy. This innovative device offers an eco-friendly alternative to traditional massagers by reducing reliance on electricity grids. The project is a result of thorough research on menstrual and general abdominal pain, its remedy, need for a solution, market survey and technical aspects like use of renewable energy, chemical experimentation, electrical design and ergonomics of product design. It is designed to provide users with a soothing massage experience, relieving muscle tension and promoting relaxation. Its versatile nature allows for indoor and outdoor use, catering to individual preferences and providing flexibility in various settings. With an emphasis on sustainability, it encourages eco-conscious living while enhancing personal well-being. In summary, the Solar Pain Reliever offers a subtle and sustainable solution for relaxation. The product provides users with a therapeutic heat and massage experience while attempting to minimize environmental impact. Keywords: Solar Energy, Electric Energy, Power generation, therapeutic experience

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Fontani, D., P. Sansoni, E. Sani, S. Coraggia, D. Jafrancesco e L. Mercatelli. "Solar Divergence Collimators for Optical Characterisation of Solar Components". International Journal of Photoenergy 2013 (2013): 1–10. http://dx.doi.org/10.1155/2013/610173.

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Abstract (sommario):

Experimentation and laboratory optical tests on solar components are central aspects of the research on renewable energies. The key element of the proposed testing systems is a solar divergence collimator, which exactly reproduces in laboratory the sunlight divergence, while commercial solar simulators are mainly aimed to replicate intensity and spectrum of the sun. Precise solar divergence reproduction is essential to correctly assess the optical properties and to simulate the operative conditions of a solar collecting device. Optical characterisation and experimentation can give information about production quality and homogeneity; moreover, specific tests can address the serial production of solar components detecting defects type and location. For Concentrating Photovoltaic systems, appropriate tests can analyze solar concentrators of various shapes, dimensions, and collection features. Typically, to characterise a solar component the most important and commonly examined quantities are collection efficiency, image plane analysis, and angle dependence.

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Mitchell, John. "Simulation or Experimentation for HVAC Systems?" HVAC&R Research 3, n. 1 (1 gennaio 1997): 1–2. http://dx.doi.org/10.1080/10789669.1997.10391357.

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Issaq, Sonia Z., Shamil K. Talal e Aasim A. Azooz. "Experimentation on enhancement of solar still performance". International Journal of Renewable Energy Development 12, n. 4 (23 maggio 2023): 691–701. http://dx.doi.org/10.14710/ijred.2023.53239.

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This work presents new results from controlled experiments using well-designed and constructed single-inclination solar stills. The aim of these experiments is to explore methods for enhancing still performance by studying the individual effects of three types of methods. Specifically, the experiments investigate the actual effects of still basin water depth, the use of a sensible heat storage medium, and the treatment of the inner glass surface with waxy substances. The main distinction in this work is the use of solar stills that can achieve thermal efficiencies in excess of 40% under favourable weather conditions without any modification. This high efficiency level allows for meaningful analysis of the impact of modifications on still performance. The results indicate that still yield, productivity, and thermal efficiency decrease significantly when the water depth in the basin exceeds 6 cm. additionally, introducing black gravel in excess of a 2% gravel to water mass ratio in the still basin does not produce a significant change in still thermal efficiency. Treatment of the still inner glass surface with two types of waxy materials resulted in large drop in still performance.

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Ben Kassem, M. J., Joseph Saillard e Ali Khenchaf. "BISAR MAPPING II TREATMENT, SIMULATION AND EXPERIMENTATION". Progress In Electromagnetics Research 61 (2006): 67–87. http://dx.doi.org/10.2528/pier06012403.

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El-Hasan, Tareq S. "Modelling, Simulation and Experimentation of PM Spring". International Review on Modelling and Simulations (IREMOS) 9, n. 2 (30 aprile 2016): 56. http://dx.doi.org/10.15866/iremos.v9i2.8612.

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Manzur, Laura, Jorge Mario Ulloa, Mario Sánchez e Jorge Villalobos. "xArchiMate: Enterprise Architecture simulation, experimentation and analysis". SIMULATION 91, n. 3 (marzo 2015): 276–301. http://dx.doi.org/10.1177/0037549715575188.

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Couderc, Ph, J. Callenaere, J. Der Hagopian, G. Ferraris, A. Kassai, Y. Borjesson, L. Verdillon e S. Gaimard. "VEHICLE DRIVELINE DYNAMIC BEHAVIOUR: EXPERIMENTATION AND SIMULATION". Journal of Sound and Vibration 218, n. 1 (novembre 1998): 133–57. http://dx.doi.org/10.1006/jsvi.1998.1808.

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Sugiartha, Nyoman. "Experimentation of an Activated Carbon/Methanol Solar Refrigerator". Logic : Jurnal Rancang Bangun dan Teknologi 20, n. 2 (30 luglio 2020): 129–34. http://dx.doi.org/10.31940/logic.v20i2.1822.

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Lemmini, Fatiha, e Abdelmoussehel Errougani. "Experimentation of a solar adsorption refrigerator in Morocco". Renewable Energy 32, n. 15 (dicembre 2007): 2629–41. http://dx.doi.org/10.1016/j.renene.2007.01.004.

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Huang, Ping Lu, e Cong Xin Chen. "Study on Stability of Consequent Rock Slope by Simulation Experiment". Advanced Materials Research 261-263 (maggio 2011): 1470–74. http://dx.doi.org/10.4028/www.scientific.net/amr.261-263.1470.

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Abstract (sommario):

Based on similarity theory, the geologic mechanics model is established and to be used for studying distortion and breakage mechanism of consequent rock slope. The paper introduces the design and process of the experimentation. Through experimentation of a slope model, the stability of a slope is studied. After analyzing the phenomenon and data of the experimentation, it is found that the major deformation model is slippage. The mode of breakage is sliding and fracturing. The process of slippage is graded. The more hinder the position of coast is, the smaller the obliquity of rip face is. The deformation and breakage of bedding slope firstly arises at the dig face near the earth's surface.

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Jiang, Zhan Si, Hui Jiang, Yi Zhong Wu e Jia Wei Xiang. "Simulation Based Model Experimentation with Minimum Solving Strategy". Advanced Materials Research 97-101 (marzo 2010): 2851–54. http://dx.doi.org/10.4028/www.scientific.net/amr.97-101.2851.

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The process of model experimentation can be regarded as repeatedly evaluating simulation models by varying parameters of the model. At present, the solvers of simulation tools usually need to calculate all the coupling blocks during every simulating run after parameters varying. In order to greatly improve the efficiency of the process of repetitious simulation, a new method named minimum solving strategy is proposed and implemented. By this method, carrying out model experimentation with different parameters values only need to calculate the solving sequence influenced by parameters altering.

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Twarog, Kyle, Ossama Mannaa, Chih-Jen Sung e Hukam C. Mongia. "On integrated experimentation and simulation of a counter-turning swirling mixer, part I: Experimentation". Aerospace Science and Technology 119 (dicembre 2021): 107186. http://dx.doi.org/10.1016/j.ast.2021.107186.

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Fachada, Nuno, e Nuno David. "Artificial Intelligence in Modeling and Simulation". Algorithms 17, n. 6 (15 giugno 2024): 265. http://dx.doi.org/10.3390/a17060265.

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Abstract (sommario):

Modeling and simulation (M&S) serve as essential tools in various scientific and engineering domains, enabling the representation of complex systems and processes without the constraints of physical experimentation [1]. [...]

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Deng, J. S., e A. I. Isayev. "Injection Molding of Rubber Compounds: Experimentation and Simulation". Rubber Chemistry and Technology 64, n. 2 (1 maggio 1991): 296–324. http://dx.doi.org/10.5254/1.3538560.

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Abstract Results of experimental and theoretical studies of injection molding of rubber compounds have been reported. Characterizations on the rheological properties and the vulcanization kinetics of rubber compounds were carried out by means of MPT and DSC, respectively. The models were employed to fit these experimental data. An attempt has been made in extending the proposed empirical kinetic model based on DSC data to similar curing data obtained by means of the MDR technique. The heat-transfer effect due to the large sample size used in MDR measurements has been found to have a small effect on the kinetic data. Due to the different principle of state-of-cure measurements in MDR and DSC, the model parameters of curing kinetics have been found to be different in these measurements. A two-dimensional flow simulation of generalized Newtonian fluids based on both finite-difference and finite-element methods has been performed. The pressure development at various positions along the flow path during the filling stage of the molds was obtained experimentally for various injection speeds. The predicted results on pressure development during cavity filling showed qualitative agreement with the experimental data. Possible reasons for the observed discrepancy in pressure traces are: neglect of local extra pressure losses (in the juncture sections), compressibility of rubber compounds, leakage (back-flow) of material during injection, and voids formation in the injection chamber. The study on the vulcanization behavior of rubber compounds during injection molding process has also been done. The proposed empirical kinetic and induction time models were able to satisfactorily predict the cure levels of molded rubber products. At the same time, the results predicted by employing nth order kinetics were found to be unsatisfactory. The contribution of nonisothermal induction time in calculating cure levels of the molded rubber products was found to be significant. The mechanical properties and anisotropy have been investigated for two rubber compounds. It is suggested that there exists a mold temperature at which the properties and cycle times are optimal, and the filler type shows a significant effect on the tensile modulus. The rubber moldings were found to be highly anisotropic in mechanical behaviors. The anisotropy could be reduced significantly at high injection speed due to the faster stress-relaxation process.

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Grosdidier, Samuel, Philippe Forget, Yves Barbin e Charles-Antoine Guerin. "HF Bistatic Ocean Doppler Spectra: Simulation Versus Experimentation". IEEE Transactions on Geoscience and Remote Sensing 52, n. 4 (aprile 2014): 2138–48. http://dx.doi.org/10.1109/tgrs.2013.2258352.

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Manlig, František, Radek Havlik e Alena Gottwaldova. "Settings, Experimentation and Evaluation of the Simulation Models". Applied Mechanics and Materials 309 (febbraio 2013): 366–71. http://dx.doi.org/10.4028/www.scientific.net/amm.309.366.

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This paper deals with research in computer simulation of manufacturing processes. The paper summarizes the procedures associated with developing the model, experimenting with and evaluating the model results. The key area is of experimentation with the simulation model and evaluation using indicators or multi-criteria functions. With regards to the experiment the crucial variables are the simulation model. The key ideas are to set the number of variables, depending on what a given simulation will be. For example, when introducing new technology into production, modify the type of warehouse, saving workers, thus economizing. The simulation models for the operational management uses simplified models, if possible, a minimum number of variables to obtain the result in shortest possible time. These models are more user friendly and the course will be conducted mostly in the background. An example of a criteria function is the number of parts produced or production time. Multi-criteria function has given us the opportunity to make better quality decisions. It is based on the composition of several parameters, including their weight to one end point. The type of evaluation functions, whether it is an indicator or criteria function is selected and based on customer requirements. In most cases it is recommended to use the multi-dimensional function. It gives us a more comprehensive view of the results from the model and facilitates decision-making. The result of this paper is a display of setting parameters for the experimentation on a sample model. Furthermore, the comparisons of results with a multi-criteria objective function and one-criterion indicator.

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Fowlkes, JD, DA Smith e PD Rack. "Electron Beam Induced Processing: Experimentation, Simulation, and Applications". Microscopy and Microanalysis 14, S2 (agosto 2008): 1196–97. http://dx.doi.org/10.1017/s1431927608083633.

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Aoustin, Yannick, Alexander Formal’sky e Christine Chevallereau. "Virtual quadruped: Mechanical design, control, simulation, and experimentation". Journal of Mathematical Sciences 147, n. 2 (novembre 2007): 6552–68. http://dx.doi.org/10.1007/s10958-007-0495-5.

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Giere, Ronald N. "Is computer simulation changing the face of experimentation?" Philosophical Studies 143, n. 1 (10 gennaio 2009): 59–62. http://dx.doi.org/10.1007/s11098-008-9314-1.

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Sage, Andrew P. "Simulation and model driven experimentation in systems engineering". Systems Engineering 2, n. 2 (1999): 57–61. http://dx.doi.org/10.1002/(sici)1520-6858(1999)2:2<57::aid-sys1>3.0.co;2-d.

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Lemmini, F., e A. Errougani. "Building and experimentation of a solar powered adsorption refrigerator". Renewable Energy 30, n. 13 (ottobre 2005): 1989–2003. http://dx.doi.org/10.1016/j.renene.2005.03.003.

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Carreira, Susana, Ana Margarida Baioa e Lourdes Maria Werle de Almeida. "Mathematical models and meanings by school and university students in a modelling task". Avances de Investigación en Educación Matemática, n. 17 (1 maggio 2020): 67–83. http://dx.doi.org/10.35763/aiem.v0i17.308.

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This study involves two classes from different educational levels, namely 9th grade and university. Students in both contexts were given a modelling task that required the development of a hand biometrics recognition system, during which they performed experimentation and simulation. As aims of the study, we look for distinctions and commonalities between the models developed in the two classes and seek to know how simulation and experimentation influence students’ production of meaning. The theoretical framework comprises the relationship between the modelling process and the prototyping process and adopts Peirce’s pragmatic perspective on meaning. The research is of a qualitative nature, assuming the characteristics of a case study. The results reveal many commonalities between the modelling in the two contexts. Moreover, experimentation and simulation were relevant elements for the production of meaning by the students, which is endorsed by a pragmatic perspective on meaning.

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Propst, Annabeth L., e Donald J. Wheeler. "Understanding Industrial Experimentation". Technometrics 31, n. 4 (novembre 1989): 480. http://dx.doi.org/10.2307/1269999.

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Ziegel, Eric R., e Donald J. Wheeler. "Understanding Industrial Experimentation". Technometrics 34, n. 3 (agosto 1992): 370. http://dx.doi.org/10.2307/1270066.

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Bathe, Klaus-Jürgen. "Crush Simulation of Cars with FEA". Mechanical Engineering 120, n. 11 (1 novembre 1998): 82–83. http://dx.doi.org/10.1115/1.1998-nov-6.

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This article illustrates that while crash analyses have been carried out with success, a crush analysis is much more difficult to achieve. In a crash analysis, the inertia effects smooth out the nonlinearities and deficiencies in the solution algorithms. In a crush test, it takes about 10 to 30 seconds to crush the car to the required maximum displacement of the steel plate. Since the critical time step for explicit time integration in a crash code is on the order of microseconds, millions of time steps must be used to perform the analysis in a physically correct manner. With sufficient numerical experimentation, involving changes to the load application speed and perhaps to other parameters, LSDYNA results can be obtained that would match laboratory test results, but such experimentation requires a lot of time and computational effort. A solution that corresponds to the actual physical conditions and is computationally efficient is much more desirable. Such a computed solution is given above for a Ford Taurus model. The calculated crush results obtained with ADINA using implicit integration compare favorably with the laboratory test results.

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