Search results for: forward modeling
4797 Sun-Driven Evaporation Enhanced Forward Osmosis Process for Application in Wastewater Treatment and Pure Water Regeneration
Authors: Dina Magdy Abdo, Ayat N. El-Shazly, E. A. Abdel-Aal
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Forward osmosis (FO) is one of the important processes during the wastewater treatment system for environmental remediation and fresh water regeneration. Both Egypt and China are troubled by over millions of tons of wastewater every year, including domestic and industrial wastewater. However, the traditional FO process in wastewater treatment usually suffers low efficiency and high energy consumption because of the continuously diluted draw solution. An additional concentration process is necessary to keep running of FO separation, causing energy waste. Based on the previous study on photothermal membrane, a sun-driven evaporation process is integrated into the draw solution side of FO system. During the sun-driven evaporation, not only the draw solution can be concentrated to maintain a stable and sustainable FO system, but fresh water can be directly separated for regeneration. Solar energy is the ultimate energy source of everything we have on Earth and is, without any doubt, the most renewable and sustainable energy source available to us. Additionally, the FO membrane process is rationally designed to limit the concentration polarization and fouling. The FO membrane’s structure and surface property will be further optimized by the adjustment of doping ratio of controllable nano-materials, membrane formation conditions, and selection of functional groups. A novel kind of nano-composite functional separation membrane with bi-interception layers and high hydrophilicity will be developed for the application in wastewater treatment. So, herein we aim to design a new wastewater treatment system include forward osmosis with high-efficiency energy recovery via the integration of photothermal membrane.Keywords: forward osmosis, membrane, solar, water treatement
Procedia PDF Downloads 744796 Threat Modeling Methodology for Supporting Industrial Control Systems Device Manufacturers and System Integrators
Authors: Raluca Ana Maria Viziteu, Anna Prudnikova
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Industrial control systems (ICS) have received much attention in recent years due to the convergence of information technology (IT) and operational technology (OT) that has increased the interdependence of safety and security issues to be considered. These issues require ICS-tailored solutions. That led to the need to creation of a methodology for supporting ICS device manufacturers and system integrators in carrying out threat modeling of embedded ICS devices in a way that guarantees the quality of the identified threats and minimizes subjectivity in the threat identification process. To research, the possibility of creating such a methodology, a set of existing standards, regulations, papers, and publications related to threat modeling in the ICS sector and other sectors was reviewed to identify various existing methodologies and methods used in threat modeling. Furthermore, the most popular ones were tested in an exploratory phase on a specific PLC device. The outcome of this exploratory phase has been used as a basis for defining specific characteristics of ICS embedded devices and their deployment scenarios, identifying the factors that introduce subjectivity in the threat modeling process of such devices, and defining metrics for evaluating the minimum quality requirements of identified threats associated to the deployment of the devices in existing infrastructures. Furthermore, the threat modeling methodology was created based on the previous steps' results. The usability of the methodology was evaluated through a set of standardized threat modeling requirements and a standardized comparison method for threat modeling methodologies. The outcomes of these verification methods confirm that the methodology is effective. The full paper includes the outcome of research on different threat modeling methodologies that can be used in OT, their comparison, and the results of implementing each of them in practice on a PLC device. This research is further used to build a threat modeling methodology tailored to OT environments; a detailed description is included. Moreover, the paper includes results of the evaluation of created methodology based on a set of parameters specifically created to rate threat modeling methodologies.Keywords: device manufacturers, embedded devices, industrial control systems, threat modeling
Procedia PDF Downloads 584795 A Comparative Study on Creep Modeling in Composites
Authors: Roham Rafiee, Behzad Mazhari
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Composite structures, having incredible properties, have gained considerable popularity in the last few decades. Among all types, polymer matrix composites are being used extensively due to their unique characteristics including low weight, convenient fabrication process and low cost. Having polymer as matrix, these type of composites show different creep behavior when compared to metals and even other types of composites since most polymers undergo creep even in room temperature. One of the most challenging topics in creep is to introduce new techniques for predicting long term creep behavior of materials. Depending on the material which is being studied the appropriate method would be different. Methods already proposed for predicting long term creep behavior of polymer matrix composites can be divided into five categories: (1) Analytical Modeling, (2) Empirical Modeling, (3) Superposition Based Modeling (Semi-empirical), (4) Rheological Modeling, (5) Finite Element Modeling. Each of these methods has individual characteristics. Studies have shown that none of the mentioned methods can predict long term creep behavior of all PMC composites in all circumstances (loading, temperature, etc.) but each of them has its own priority in different situations. The reason to this issue can be found in theoretical basis of these methods. In this study after a brief review over the background theory of each method, they are compared in terms of their applicability in predicting long-term behavior of composite structures. Finally, the explained materials are observed through some experimental studies executed by other researchers.Keywords: creep, comparative study, modeling, composite materials
Procedia PDF Downloads 4134794 Atmospheric Oxidation of Carbonyls: Insight to Mechanism, Kinetic and Thermodynamic Parameters
Authors: Olumayede Emmanuel Gbenga, Adeniyi Azeez Adebayo
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Carbonyls are the first-generation products from tropospheric degradation reactions of volatile organic compounds (VOCs). This computational study examined the mechanism of removal of carbonyls from the atmosphere via hydroxyl radical. The kinetics of the reactions were computed from the activation energy (using enthalpy (ΔH**) and Gibbs free energy (ΔG**). The minimum energy path (MEP) analysis reveals that in all the molecules, the products have more stable energy than the reactants, which implies that the forward reaction is more thermodynamically favorable. The hydrogen abstraction of the aromatic aldehyde, especially without methyl substituents, is more kinetically favorable compared with the other aldehydes in the order of aromatic (without methyl or meta methyl) > alkene (short chain) > diene > long-chain aldehydes. The activation energy is much lower for the forward reaction than the backward, indicating that the forward reactions are more kinetically stable than their backward reaction. In terms of thermodynamic stability, the aromatic compounds are found to be less favorable in comparison to the aliphatic. The study concludes that the chemistry of the carbonyl bond of the aldehyde changed significantly from the reactants to the products.Keywords: atmospheric carbonyls, oxidation, mechanism, kinetic, thermodynamic
Procedia PDF Downloads 204793 Individual Actuators of a Car-Like Robot with Back Trailer
Authors: Tarek El-Derini, Ahmed El-Shenawy
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This paper presents the hardware implemented and validation for a special system to assist the unprofessional users of car with back trailers. The system consists of two platforms; the front car platform (C) and the trailer platform (T). The main objective is to control the Trailer platform using the actuators found in the front platform (c). The mobility of the platform (C) is investigated and inverse and forward kinematics model is obtained for both platforms (C) and (T). The system is simulated using Matlab M-file and the simulation examples results illustrated the system performance. The system is constructed with a hardware setup for the front and trailer platform. The hardware experimental results and the simulated examples outputs showed the validation of the hardware setup.Keywords: kinematics, modeling, robot, MATLAB
Procedia PDF Downloads 4164792 From Modeling of Data Structures towards Automatic Programs Generating
Authors: Valentin P. Velikov
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Automatic program generation saves time, human resources, and allows receiving syntactically clear and logically correct modules. The 4-th generation programming languages are related to drawing the data and the processes of the subject area, as well as, to obtain a frame of the respective information system. The application can be separated in interface and business logic. That means, for an interactive generation of the needed system to be used an already existing toolkit or to be created a new one.Keywords: computer science, graphical user interface, user dialog interface, dialog frames, data modeling, subject area modeling
Procedia PDF Downloads 2834791 Hybrid Artificial Bee Colony and Least Squares Method for Rule-Based Systems Learning
Authors: Ahcene Habbi, Yassine Boudouaoui
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This paper deals with the problem of automatic rule generation for fuzzy systems design. The proposed approach is based on hybrid artificial bee colony (ABC) optimization and weighted least squares (LS) method and aims to find the structure and parameters of fuzzy systems simultaneously. More precisely, two ABC based fuzzy modeling strategies are presented and compared. The first strategy uses global optimization to learn fuzzy models, the second one hybridizes ABC and weighted least squares estimate method. The performances of the proposed ABC and ABC-LS fuzzy modeling strategies are evaluated on complex modeling problems and compared to other advanced modeling methods.Keywords: automatic design, learning, fuzzy rules, hybrid, swarm optimization
Procedia PDF Downloads 4114790 Causal Modeling of the Glucose-Insulin System in Type-I Diabetic Patients
Authors: J. Fernandez, N. Aguilar, R. Fernandez de Canete, J. C. Ramos-Diaz
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In this paper, a simulation model of the glucose-insulin system for a patient undergoing diabetes Type 1 is developed by using a causal modeling approach under system dynamics. The OpenModelica simulation environment has been employed to build the so called causal model, while the glucose-insulin model parameters were adjusted to fit recorded mean data of a diabetic patient database. Model results under different conditions of a three-meal glucose and exogenous insulin ingestion patterns have been obtained. This simulation model can be useful to evaluate glucose-insulin performance in several circumstances, including insulin infusion algorithms in open-loop and decision support systems in closed-loop.Keywords: causal modeling, diabetes, glucose-insulin system, diabetes, causal modeling, OpenModelica software
Procedia PDF Downloads 3074789 Macro Corruption: A Conceptual Analysis of Its Dimensions and Forward and Backward Linkages
Authors: Ahmed Sakr Ashour, Hoda Saad AboRemila
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An attempt was made to fill the gap in the macro analysis of corruption by suggesting a conceptual framework that differentiates four types of macro corruption: state capture, political, bureaucratic and financial/corporate. The economic consequences or forward linkages (growth, inclusiveness and sustainability of development) and macro institutional determinants constituting the backward linkages of each type were delineated. The research implications of the macro perspective and proposed framework were discussed. Implications of the findings for theory, research and reform policies addressing macro corruption issues were discussed.Keywords: economic growth, inclusive growth, macro corruption, sustainable development
Procedia PDF Downloads 1504788 An intelligent Troubleshooting System and Performance Evaluator for Computer Network
Authors: Iliya Musa Adamu
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This paper seeks to develop an expert system that would troubleshoot computer network and evaluate the network system performance so as to reduce the workload on technicians and increase the efficiency and effectiveness of solutions proffered to computer network problems. The platform of the system was developed using ASP.NET, whereas the codes are implemented in Visual Basic and integrated with SQL Server 2005. The knowledge base was represented using production rule, whereas the searching method that was used in developing the network troubleshooting expert system is the forward-chaining-rule-based-system. This software tool offers the advantage of providing an immediate solution to most computer network problems encountered by computer users.Keywords: expert system, forward chaining rule based system, network, troubleshooting
Procedia PDF Downloads 6154787 Comparative Analysis of Two Modeling Approaches for Optimizing Plate Heat Exchangers
Authors: Fábio A. S. Mota, Mauro A. S. S. Ravagnani, E. P. Carvalho
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In the present paper the design of plate heat exchangers is formulated as an optimization problem considering two mathematical modeling. The number of plates is the objective function to be minimized, considering implicitly some parameters configuration. Screening is the optimization method used to solve the problem. Thermal and hydraulic constraints are verified, not viable solutions are discarded and the method searches for the convergence to the optimum, case it exists. A case study is presented to test the applicability of the developed algorithm. Results show coherency with the literature.Keywords: plate heat exchanger, optimization, modeling, simulation
Procedia PDF Downloads 4854786 Ontology-Based Approach for Temporal Semantic Modeling of Social Networks
Authors: Souâad Boudebza, Omar Nouali, Faiçal Azouaou
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Social networks have recently gained a growing interest on the web. Traditional formalisms for representing social networks are static and suffer from the lack of semantics. In this paper, we will show how semantic web technologies can be used to model social data. The SemTemp ontology aligns and extends existing ontologies such as FOAF, SIOC, SKOS and OWL-Time to provide a temporal and semantically rich description of social data. We also present a modeling scenario to illustrate how our ontology can be used to model social networks.Keywords: ontology, semantic web, social network, temporal modeling
Procedia PDF Downloads 3524785 Multi-Agent TeleRobotic Security Control System: Requirements Definitions of Multi-Agent System Using The Behavioral Patterns Analysis (BPA) Approach
Authors: Assem El-Ansary
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This paper illustrates the event-oriented Behavioral Pattern Analysis (BPA) modeling approach in developing an Multi-Agent TeleRobotic Security Control System (MTSCS). The event defined in BPA is a real-life conceptual entity that is unrelated to any implementation. The major contributions of this research are the Behavioral Pattern Analysis (BPA) modeling methodology, and the development of an interactive software tool (DECISION), which is based on a combination of the Analytic Hierarchy Process (AHP) and the ELECTRE Multi-Criteria Decision Making (MCDM) methods.Keywords: analysis, multi-agent, TeleRobotics control, security, modeling methodology, software modeling, event-oriented, behavioral pattern, use cases
Procedia PDF Downloads 4124784 Seismic Performance Evaluation of Existing Building Using Structural Information Modeling
Authors: Byungmin Cho, Dongchul Lee, Taejin Kim, Minhee Lee
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The procedure for the seismic retrofit of existing buildings includes the seismic evaluation. In the evaluation step, it is assessed whether the buildings have satisfactory performance against seismic load. Based on the results of that, the buildings are upgraded. To evaluate seismic performance of the buildings, it usually goes through the model transformation from elastic analysis to inelastic analysis. However, when the data is not delivered through the interwork, engineers should manually input the data. In this process, since it leads to inaccuracy and loss of information, the results of the analysis become less accurate. Therefore, in this study, the process for the seismic evaluation of existing buildings using structural information modeling is suggested. This structural information modeling makes the work economic and accurate. To this end, it is determined which part of the process could be computerized through the investigation of the process for the seismic evaluation based on ASCE 41. The structural information modeling process is developed to apply to the seismic evaluation using Perform 3D program usually used for the nonlinear response history analysis. To validate this process, the seismic performance of an existing building is investigated.Keywords: existing building, nonlinear analysis, seismic performance, structural information modeling
Procedia PDF Downloads 3524783 On-Ice Force-Velocity Modeling Technical Considerations
Authors: Dan Geneau, Mary Claire Geneau, Seth Lenetsky, Ming -Chang Tsai, Marc Klimstra
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Introduction— Horizontal force-velocity profiling (HFVP) involves modeling an athletes linear sprint kinematics to estimate valuable maximum force and velocity metrics. This approach to performance modeling has been used in field-based team sports and has recently been introduced to ice-hockey as a forward skating performance assessment. While preliminary data has been collected on ice, distance constraints of the on-ice test restrict the ability of the athletes to reach their maximal velocity which result in limits of the model to effectively estimate athlete performance. This is especially true of more elite athletes. This report explores whether athletes on-ice are able to reach a velocity plateau similar to what has been seen in overground trials. Fourteen male Major Junior ice-hockey players (BW= 83.87 +/- 7.30 kg, height = 188 ± 3.4cm cm, age = 18 ± 1.2 years n = 14) were recruited. For on-ice sprints, participants completed a standardized warm-up consisting of skating and dynamic stretching and a progression of three skating efforts from 50% to 95%. Following the warm-up, participants completed three on ice 45m sprints, with three minutes of rest in between each trial. For overground sprints, participants completed a similar dynamic warm-up to that of on-ice trials. Following the warm-up participants completed three 40m overground sprint trials. For each trial (on-ice and overground), radar was used to collect instantaneous velocity (Stalker ATS II, Texas, USA) aimed at the participant’s waist. Sprint velocities were modelled using custom Python (version 3.2) script using a mono-exponential function, similar to previous work. To determine if on-ice tirals were achieving a maximum velocity (plateau), minimum acceleration values of the modeled data at the end of the sprint were compared (using paired t-test) between on-ice and overground trials. Significant differences (P<0.001) between overground and on-ice minimum accelerations were observed. It was found that on-ice trials consistently reported higher final acceleration values, indicating a maximum maintained velocity (plateau) had not been reached. Based on these preliminary findings, it is suggested that reliable HFVP metrics cannot yet be collected from all ice-hockey populations using current methods. Elite male populations were not able to achieve a velocity plateau similar to what has been seen in overground trials, indicating the absence of a maximum velocity measure. With current velocity and acceleration modeling techniques, including a dependency of a velocity plateau, these results indicate the potential for error in on-ice HFVP measures. Therefore, these findings suggest that a greater on-ice sprint distance may be required or the need for other velocity modeling techniques, where maximal velocity is not required for a complete profile.Keywords: ice-hockey, sprint, skating, power
Procedia PDF Downloads 674782 The Effectiveness of Using Video Modeling Procedures on the ipad to Teach Play Skills Children with ASD
Authors: Esra Orum Cattik
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This study evaluated the effects of using video modeling procedures on the iPad to teach play skills to children with autism spectrum disorders. A male student with autism spectrum disorders participated in this study. A multiple baseline-across-skills single-subject design was used to evaluate the effects of using video modeling procedures on the iPad. During baseline, no prompts were presented to participants. In the intervention phase, the teacher gave video model on iPad to the first skill and asked play with toys for him. When the first play skill completed the second play skill began intervention. This procedure continued till all three play skill completed intervention. Finally, the participant learned all three play skills to use video modeling presented on the iPad. Based upon findings of this study, suggestions have been made to future researches.Keywords: autism spectrum disorders, play, play skills, video modeling, single subject design
Procedia PDF Downloads 3834781 Comparative Study on Daily Discharge Estimation of Soolegan River
Authors: Redvan Ghasemlounia, Elham Ansari, Hikmet Kerem Cigizoglu
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Hydrological modeling in arid and semi-arid regions is very important. Iran has many regions with these climate conditions such as Chaharmahal and Bakhtiari province that needs lots of attention with an appropriate management. Forecasting of hydrological parameters and estimation of hydrological events of catchments, provide important information that used for design, management and operation of water resources such as river systems, and dams, widely. Discharge in rivers is one of these parameters. This study presents the application and comparison of some estimation methods such as Feed-Forward Back Propagation Neural Network (FFBPNN), Multi Linear Regression (MLR), Gene Expression Programming (GEP) and Bayesian Network (BN) to predict the daily flow discharge of the Soolegan River, located at Chaharmahal and Bakhtiari province, in Iran. In this study, Soolegan, station was considered. This Station is located in Soolegan River at 51° 14՜ Latitude 31° 38՜ longitude at North Karoon basin. The Soolegan station is 2086 meters higher than sea level. The data used in this study are daily discharge and daily precipitation of Soolegan station. Feed Forward Back Propagation Neural Network(FFBPNN), Multi Linear Regression (MLR), Gene Expression Programming (GEP) and Bayesian Network (BN) models were developed using the same input parameters for Soolegan's daily discharge estimation. The results of estimation models were compared with observed discharge values to evaluate performance of the developed models. Results of all methods were compared and shown in tables and charts.Keywords: ANN, multi linear regression, Bayesian network, forecasting, discharge, gene expression programming
Procedia PDF Downloads 5344780 Analytical Investigation of Modeling and Simulation of Different Combinations of Sinusoidal Supplied Autotransformer under Linear Loading Conditions
Authors: M. Salih Taci, N. Tayebi, I. Bozkır
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This paper investigates the operation of a sinusoidal supplied autotransformer on the different states of magnetic polarity of primary and secondary terminals for four different step-up and step-down analytical conditions. In this paper, a new analytical modeling and equations for dot-marked and polarity-based step-up and step-down autotransformer are presented. These models are validated by the simulation of current and voltage waveforms for each state. PSpice environment was used for simulation.Keywords: autotransformer modeling, autotransformer simulation, step-up autotransformer, step-down autotransformer, polarity
Procedia PDF Downloads 2854779 Determination of Aquifer Geometry Using Geophysical Methods: A Case Study from Sidi Bouzid Basin, Central Tunisia
Authors: Dhekra Khazri, Hakim Gabtni
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Because of Sidi Bouzid water table overexploitation, this study aims at integrating geophysical methods to determinate aquifers geometry assessing their geological situation and geophysical characteristics. However in highly tectonic zones controlled by Atlassic structural features with NE-SW major directions (central Tunisia), Bouguer gravimetric responses of some areas can be as much dominated by the regional structural tendency, as being non-identified or either defectively interpreted such as the case of Sidi Bouzid basin. This issue required a residual gravity anomaly elaboration isolating the Sidi Bouzid basin gravity response ranging between -8 and -14 mGal and crucial for its aquifers geometry characterization. Several gravity techniques helped constructing the Sidi Bouzid basin's residual gravity anomaly, such as Upwards continuation compared to polynomial regression trends and power spectrum analysis detecting deep basement sources at (3km), intermediate (2km) and shallow sources (1km). A 3D Euler Deconvolution was also performed detecting deepest accidents trending NE-SW, N-S and E-W with depth values reaching 5500 m and delineating the main outcropping structures of the study area. Further gravity treatments highlighted the subsurface geometry and structural features of Sidi Bouzid basin over Horizontal and vertical gradient, and also filters based on them such as Tilt angle and Source Edge detector locating rooted edges or peaks from potential field data detecting a new E-W lineament compartmentalizing the Sidi Bouzid gutter into two unequally residual anomaly and subsiding domains. This subsurface morphology is also detected by the used 2D seismic reflection sections defining the Sidi Bouzid basin as a deep gutter within a tectonic set of negative flower structures, and collapsed and tilted blocks. Furthermore, these structural features were confirmed by forward gravity modeling process over several modeled residual gravity profiles crossing the main area. Sidi Bouzid basin (central Tunisia) is also of a big interest cause of the unknown total thickness and the undefined substratum of its siliciclastic Tertiary package, and its aquifers unbounded structural subsurface features and deep accidents. The Combination of geological, hydrogeological and geophysical methods is then of an ultimate need. Therefore, a geophysical methods integration based on gravity survey supporting available seismic data through forward gravity modeling, enhanced lateral and vertical extent definition of the basin's complex sedimentary fill via 3D gravity models, improved depth estimation by a depth to basement modeling approach, and provided 3D isochronous seismic mapping visualization of the basin's Tertiary complex refining its geostructural schema. A subsurface basin geomorphology mapping, over an ultimate matching between the basin's residual gravity map and the calculated theoretical signature map, was also displayed over the modeled residual gravity profiles. An ultimate multidisciplinary geophysical study of the Sidi Bouzid basin aquifers can be accomplished via an aeromagnetic survey and a 4D Microgravity reservoir monitoring offering temporal tracking of the target aquifer's subsurface fluid dynamics enhancing and rationalizing future groundwater exploitation in this arid area of central Tunisia.Keywords: aquifer geometry, geophysics, 3D gravity modeling, improved depths, source edge detector
Procedia PDF Downloads 2574778 User Modeling from the Perspective of Improvement in Search Results: A Survey of the State of the Art
Authors: Samira Karimi-Mansoub, Rahem Abri
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Currently, users expect high quality and personalized information from search results. To satisfy user’s needs, personalized approaches to web search have been proposed. These approaches can provide the most appropriate answer for user’s needs by using user context and incorporating information about query provided by combining search technologies. To carry out personalized web search, there is a need to make different techniques on whole of user search process. There are the number of possible deployment of personalized approaches such as personalized web search, personalized recommendation, personalized summarization and filtering systems and etc. but the common feature of all approaches in various domains is that user modeling is utilized to provide personalized information from the Web. So the most important work in personalized approaches is user model mining. User modeling applications and technologies can be used in various domains depending on how the user collected information may be extracted. In addition to, the used techniques to create user model is also different in each of these applications. Since in the previous studies, there was not a complete survey in this field, our purpose is to present a survey on applications and techniques of user modeling from the viewpoint of improvement in search results by considering the existing literature and researches.Keywords: filtering systems, personalized web search, user modeling, user search behavior
Procedia PDF Downloads 2514777 Numerical Modeling of a Retaining Wall in Soil Reinforced by Layers of Geogrids
Authors: M. Mellas, S. Baaziz, A. Mabrouki, D. Benmeddour
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The reinforcement of massifs of backfill with horizontal layers of geosynthetics is an interesting economic solution, which ensures the stability of retaining walls. The mechanical behavior of reinforced soil by geosynthetic is complex, and requires studies and research to understand the mechanisms of rupture. The behavior of reinforcements in the soil and the behavior of the main elements of the system: reinforcement-wall-soil. The present study is interested in numerical modeling of a retaining wall in soil reinforced by horizontal layers of geogrids. This modeling makes use of the software FLAC3D. This work aims to analyze the effect of the length of the geogrid "L" where the soil massif is supporting a uniformly distributed surcharge "Q", taking into account the fixing elements rather than the layers of geogrids to the wall.Keywords: retaining wall, geogrid, reinforced soil, numerical modeling, FLAC3D
Procedia PDF Downloads 4584776 Modeling Exponential Growth Activity Using Technology: A Research with Bachelor of Business Administration Students
Authors: V. Vargas-Alejo, L. E. Montero-Moguel
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Understanding the concept of function has been important in mathematics education for many years. In this study, the models built by a group of five business administration and accounting undergraduate students when carrying out a population growth activity are analyzed. The theoretical framework is the Models and Modeling Perspective. The results show how the students included tables, graphics, and algebraic representations in their models. Using technology was useful to interpret, describe, and predict the situation. The first model, the students built to describe the situation, was linear. After that, they modified and refined their ways of thinking; finally, they created exponential growth. Modeling the activity was useful to deep on mathematical concepts such as covariation, rate of change, and exponential function also to differentiate between linear and exponential growth.Keywords: covariation reasoning, exponential function, modeling, representations
Procedia PDF Downloads 994775 Modeling of Erosion and Sedimentation Impacts from off-Road Vehicles in Arid Regions
Authors: Abigail Rosenberg, Jennifer Duan, Michael Poteuck, Chunshui Yu
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The Barry M. Goldwater Range, West in southwestern Arizona encompasses 2,808 square kilometers of Sonoran Desert. The hyper-arid range has an annual rainfall of less than 10 cm with an average high temperature of 41 degrees Celsius in July to an average low of 4 degrees Celsius in January. The range shares approximately 60 kilometers of the international border with Mexico. A majority of the range is open for recreational use, primarily off-highway vehicles. Because of its proximity to Mexico, the range is also heavily patrolled by U.S. Customs and Border Protection seeking to intercept and apprehend inadmissible people and illicit goods. Decades of off-roading and Border Patrol activities have negatively impacted this sensitive desert ecosystem. To assist the range program managers, this study is developing a model to identify erosion prone areas and calibrate the model’s parameters using the Automated Geospatial Watershed Assessment modeling tool.Keywords: arid lands, automated geospatial watershed assessment, erosion modeling, sedimentation modeling, watershed modeling
Procedia PDF Downloads 3434774 Uplift Modeling Approach to Optimizing Content Quality in Social Q/A Platforms
Authors: Igor A. Podgorny
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TurboTax AnswerXchange is a social Q/A system supporting users working on federal and state tax returns. Content quality and popularity in the AnswerXchange can be predicted with propensity models using attributes of the question and answer. Using uplift modeling, we identify features of questions and answers that can be modified during the question-asking and question-answering experience in order to optimize the AnswerXchange content quality. We demonstrate that adding details to the questions always results in increased question popularity that can be used to promote good quality content. Responding to close-ended questions assertively improve content quality in the AnswerXchange in 90% of cases. Answering knowledge questions with web links increases the likelihood of receiving a negative vote from 60% of the askers. Our findings provide a rationale for employing the uplift modeling approach for AnswerXchange operations.Keywords: customer relationship management, human-machine interaction, text mining, uplift modeling
Procedia PDF Downloads 2284773 Modeling of Silicon Window Layers for Solar Cells Based SIGE
Authors: Meriem Boukais, B. Dennai, A. Ould- Abbas
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The efficiency of SiGe solar cells might be improved by a wide-band-gap window layer. In this work we were simulated using the one dimensional simulation program called analysis of microelectronic and photonic structures (AMPS-1D). In the modeling, the thickness of silicon window was varied from 80 to 150 nm. The rest of layer’s thicknesses were kept constant, by varying thickness of window layer the simulated device performance was demonstrate in the form of current-voltage (I-V) characteristics and quantum efficiency (QE).Keywords: modeling, SiGe, AMPS-1D, quantum efficiency, conversion, efficiency
Procedia PDF Downloads 6904772 Nonlinear Modeling of the PEMFC Based on NNARX Approach
Authors: Shan-Jen Cheng, Te-Jen Chang, Kuang-Hsiung Tan, Shou-Ling Kuo
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Polymer Electrolyte Membrane Fuel Cell (PEMFC) is such a time-vary nonlinear dynamic system. The traditional linear modeling approach is hard to estimate structure correctly of PEMFC system. From this reason, this paper presents a nonlinear modeling of the PEMFC using Neural Network Auto-regressive model with eXogenous inputs (NNARX) approach. The multilayer perception (MLP) network is applied to evaluate the structure of the NNARX model of PEMFC. The validity and accuracy of NNARX model are tested by one step ahead relating output voltage to input current from measured experimental of PEMFC. The results show that the obtained nonlinear NNARX model can efficiently approximate the dynamic mode of the PEMFC and model output and system measured output consistently.Keywords: PEMFC, neural network, nonlinear modeling, NNARX
Procedia PDF Downloads 3544771 An Approach for Modeling CMOS Gates
Authors: Spyridon Nikolaidis
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A modeling approach for CMOS gates is presented based on the use of the equivalent inverter. A new model for the inverter has been developed using a simplified transistor current model which incorporates the nanoscale effects for the planar technology. Parametric expressions for the output voltage are provided as well as the values of the output and supply current to be compatible with the CCS technology. The model is parametric according the input signal slew, output load, transistor widths, supply voltage, temperature and process. The transistor widths of the equivalent inverter are determined by HSPICE simulations and parametric expressions are developed for that using a fitting procedure. Results for the NAND gate shows that the proposed approach offers sufficient accuracy with an average error in propagation delay about 5%.Keywords: CMOS gate modeling, inverter modeling, transistor current mode, timing model
Procedia PDF Downloads 4034770 Evaluation of Numerical Modeling of Jet Grouting Design Using in situ Loading Test
Authors: Reza Ziaie Moayed, Ehsan Azini
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Jet grouting (JG) is one of the methods of improving and increasing the strength and bearing of soil in which the high pressure water or grout is injected through the nozzles into the soil. During this process, a part of the soil and grout particles comes out of the drill borehole, and the other part is mixed up with the grout in place, as a result of this process, a mass of modified soil is created. The purpose of this method is to change the soil into a mixture of soil and cement, commonly known as "soil-cement". In this paper, first, the principles of high pressure injection and then the effective parameters in the JG method are described. Then, the tests on the samples taken from the columns formed from the excavation around the soil-cement columns, as well as the static loading test on the created column, are discussed. In the other part of this paper, the soil behavior models for numerical modeling in PLAXIS software are mentioned. The purpose of this paper is to evaluate the results of numerical modeling based on in-situ static loading tests. The results indicate an acceptable agreement between the results of the tests mentioned and the modeling results. Also, modeling with this software as an appropriate option for technical feasibility can be used to soil improvement using JG.Keywords: jet grouting column, soil improvement, numerical modeling, in-situ loading test
Procedia PDF Downloads 1114769 Forward Conditional Restricted Boltzmann Machines for the Generation of Music
Authors: Johan Loeckx, Joeri Bultheel
Abstract:
Recently, the application of deep learning to music has gained popularity. Its true potential, however, has been largely unexplored. In this paper, a new idea for representing the dynamic behavior of music is proposed. A ”forward” conditional RBM takes into account not only preceding but also future samples during training. Though this may sound controversial at first sight, it will be shown that it makes sense from a musical and neuro-cognitive perspective. The model is applied to reconstruct music based upon the first notes and to improvise in the musical style of a composer. Different to expectations, reconstruction accuracy with respect to a regular CRBM with the same order, was not significantly improved. More research is needed to test the performance on unseen data.Keywords: deep learning, restricted boltzmann machine, music generation, conditional restricted boltzmann machine (CRBM)
Procedia PDF Downloads 4924768 3D Modeling Approach for Cultural Heritage Structures: The Case of Virgin of Loreto Chapel in Cusco, Peru
Authors: Rony Reátegui, Cesar Chácara, Benjamin Castañeda, Rafael Aguilar
Abstract:
Nowadays, heritage building information modeling (HBIM) is considered an efficient tool to represent and manage information of cultural heritage (CH). The basis of this tool relies on a 3D model generally obtained from a cloud-to-BIM procedure. There are different methods to create an HBIM model that goes from manual modeling based on the point cloud to the automatic detection of shapes and the creation of objects. The selection of these methods depends on the desired level of development (LOD), level of information (LOI), grade of generation (GOG), as well as on the availability of commercial software. This paper presents the 3D modeling of a stone masonry chapel using Recap Pro, Revit, and Dynamo interface following a three-step methodology. The first step consists of the manual modeling of simple structural (e.g., regular walls, columns, floors, wall openings, etc.) and architectural (e.g., cornices, moldings, and other minor details) elements using the point cloud as reference. Then, Dynamo is used for generative modeling of complex structural elements such as vaults, infills, and domes. Finally, semantic information (e.g., materials, typology, state of conservation, etc.) and pathologies are added within the HBIM model as text parameters and generic models families, respectively. The application of this methodology allows the documentation of CH following a relatively simple to apply process that ensures adequate LOD, LOI, and GOG levels. In addition, the easy implementation of the method as well as the fact of using only one BIM software with its respective plugin for the scan-to-BIM modeling process means that this methodology can be adopted by a larger number of users with intermediate knowledge and limited resources since the BIM software used has a free student license.Keywords: cloud-to-BIM, cultural heritage, generative modeling, HBIM, parametric modeling, Revit
Procedia PDF Downloads 121