Search results for: active appearance models.
1611 Liquid-Liquid Equilibrium Data for Butan-2-ol - Ethanol - Water, Pentan-1-ol - Ethanol - Water and Toluene - Acetone - Water Systems
Authors: Tinuade Jolaade Afolabi, Theresa Ibibia Edewor
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Experimental liquid-liquid equilibra of butan-2-ol - ethanol -water; pentan-1-ol - ethanol - water and toluene - acetone - water ternary systems were investigated at (25oC). The reliability of the experimental tie-line data was ascertained by using Othmer-Tobias and Hand plots. The distribution coefficients (D) and separation factors (S) of the immiscibility region were evaluated for the three systems.Keywords: Distribution coefficient, Liquid-liquid equilibrium, separation factors, thermodynamic models
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 38391610 Evaluation of Research in the Field of Energy Efficiency and MCA Methods Using Publications Databases
Authors: Juan Sepúlveda
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Energy is a fundamental component in sustainability, the access and use of this resource is related with economic growth, social improvements, and environmental impacts. In this sense, energy efficiency has been studied as a factor that enhances the positive impacts of energy in communities; however, the implementation of efficiency requires strong policy and strategies that usually rely on individual measures focused in independent dimensions. In this paper, the problem of energy efficiency as a multi-objective problem is studied, using scientometric analysis to discover trends and patterns that allow to identify the main variables and study approximations related with a further development of models to integrate energy efficiency and MCA into policy making for small communities.Keywords: Energy efficiency, MCA, Scientometrics, trends.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 17471609 A Case Study: Experiences with Building an Online Exhibition System using Web Services
Authors: Atakan Kurt, Arzu Naiboğlu
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We present an implementation of an Online Exhibition System (OES) web service(s) that reflects our experiences with using web service development packages and software process models. The system provides major functionality that exists in similar packages. While developing such a complex web service, we gained insightful experience (i) in the traditional software development processes: waterfall model and evolutionary development and their fitness to web services development, (ii) in the fitness and effectiveness of a major web services development kit.
Keywords: Web Services, Online Exhibition System, Software Engineering, Waterfall Model, e-business.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 20551608 On the Perfomance of Multiband OFDM under Log-normal Channel Fading
Authors: N.M. Anas, S.K.S. Yusoff, R. Mohamad
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A modified Saleh-Valenzuela channel model has been adapted for Ultra Wideband (UWB) system. The suggested realistic channel is assessed by its distribution of fading amplitude and time of arrivals. Furthermore, the propagation characteristic has been distinct into four channel models, namely CM 1 to 4. Each are differentiate in terms of cluster arrival rates, rays arrival rate within each cluster and its respective constant decay rates. This paper described the multiband OFDM system performance simulates under these multipath conditions. Simulation work described in this paper is based on WiMedia ECMA-368 standard, which has been deployed for practical implementation of low cost and low power UWB devices.Keywords: Log-Normal, Multiband OFDM, Saleh-Valenzuela
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 17781607 Numerical Flow Simulation around HSP Propeller in Open Water and behind a Vessel Wake Using RANS CFD Code
Authors: Kadda Boumediene, Mohamed Bouzit
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The prediction of the flow around marine propellers and vessel hulls propeller interaction is one of the challenges of Computational fluid dynamics (CFD). The CFD has emerged as a potential tool in recent years and has promising applications. The objective of the current study is to predict the hydrodynamic performances of HSP marine propeller in open water and behind a vessel. The unsteady 3-D flow was modeled numerically along with respectively the K-ω standard and K-ω SST turbulence models for steady and unsteady cases. The hydrodynamic performances such us a torque and thrust coefficients and efficiency show good agreement with the experiment results.
Keywords: Seiun Maru propeller, steady, unsteady, CFD, HSP.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 8381606 Qanat (Subterranean Canal) Role in Traditional Cities and Settlements Formation of Hot-Arid Regions of Iran
Authors: Karim Shiraazi, Mahyar Asheghi Milani, Alireza Sadeghi, Eram Azami, Ahadollah Azami
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A passive system "Qanat" is collection of some underground wells. A mother-well was dug in a place far from the city where they could reach to the water table maybe 100 meters underground, they dug other wells to direct water toward the city, with minimum possible gradient. Using the slope of the earth they could bring water close to the surface in the city. The source of water or the appearance of Qanat, land slope and the ownership lines are the important and effective factors in the formation of routes and the segment division of lands to the extent that making use of Qanat as the techniques of extracting underground waters creates a channel of routes with an organic order and hierarchy coinciding the slope of land and it also guides the Qanat waters in the tradition texture of salt desert and border provinces of it. Qanats are excavated in a specified distinction from each other. The quantity of water provided by Qanats depends on the kind of land, distance from mountain, geographical situation of them and the rate of water supply from the underground land. The rate of underground waters, possibility of Qanat excavation, number of Qanats and rate of their water supply from one hand and the quantity of cultivable fertile lands from the other hand are the important natural factors making the size of cities. In the same manner the cities with several Qanats have multi central textures. The location of cities is in direct relation with land quality, soil fertility and possibility of using underground water by excavating Qanats. Observing the allowable distance for Qanat watering is a determining factor for distance between villages and cities. Topography, land slope, soil quality, watering system, ownership, kind of cultivation, etc. are the effective factors in directing Qanats for excavation and guiding water toward the cultivable lands and it also causes the formation of different textures in land division of farming provinces. Several divisions such as orderly and wide, inorderly, thin and long, comb like, etc. are the introduction to organic order. And at the same time they are complete coincidence with environmental conditions in the typical development of ecological architecture and planning in the traditional cities and settlements order.Keywords: Qanat, Settlement Formation, Hot-Arid Region, Sustainable Development
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 19181605 Multi-Criteria Optimization of High-Temperature Reversed Starter-Generator
Authors: Flur R. Ismagilov, Irek Kh. Khayrullin, Vyacheslav E. Vavilov, Ruslan D. Karimov, Anton S. Gorbunov, Danis R. Farrakhov
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The paper presents another structural scheme of high-temperature starter-generator with external rotor to be installed on High Pressure Shaft (HPS) of aircraft engines (AE) to implement More Electrical Engine concept. The basic materials to make this starter-generator (SG) were selected and justified. Multi-criteria optimization of the developed structural scheme was performed using a genetic algorithm and Pareto method. The optimum (in Pareto terms) active length and thickness of permanent magnets of SG were selected as a result of the optimization. Using the dimensions obtained, allowed to reduce the weight of the designed SG by 10 kg relative to a base option at constant thermal loads. Multidisciplinary computer simulation was performed on the basis of the optimum geometric dimensions, which proved performance efficiency of the design. We further plan to make a full-scale sample of SG of HPS and publish the results of its experimental research.Keywords: High-temperature starter-generator, More electrical engine, multi-criteria optimization, permanent magnet.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 12131604 Finite Element Prediction of Hip Fracture during a Sideways Fall
Authors: M. Ikhwan Z. Ridzwan, Bidyut Pal, Ulrich N. Hansen
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Finite element method was applied to model damage development in the femoral neck during a sideways fall. The femoral failure was simulated using the maximum principal strain criterion. The evolution of damage was consistent with previous studies. It was initiated by compressive failure at the junction of the superior aspect of the femoral neck and the greater trochanter. It was followed by tensile failure that occurred at the inferior aspect of the femoral neck before a complete transcervical fracture was observed. The estimated failure line was less than 50° from the horizontal plane (Pauwels type II).Keywords: Femoral Strength, Finite Element Models, Hip Fracture, Progressive Failure, Sideways Fall.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 23521603 A Contribution to the Application of the Structural Analysis Method in Entrepreneurial Practice
Authors: Kamila Janovská, Šárka Vilamová, Petr Besta, Iveta Vozňáková, Roman Kozel
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Quantitative methods of economic decision-making as the methodological base of the so called operational research represent an important set of tools for managing complex economic systems,both at the microeconomic level and on the macroeconomic scale. Mathematical models of controlled and controlling processes allow, by means of artificial experiments, obtaining information foroptimalor optimum approaching managerial decision-making.The quantitative methods of economic decision-making usually include a methodology known as structural analysis -an analysisof interdisciplinary production-consumption relations.Keywords: economic decision-making, mathematical methods, structuralanalysis, technical coefficient
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 14411602 New Design Methodologies for High Speed Low Power XOR-XNOR Circuits
Authors: Shiv Shankar Mishra, S. Wairya, R. K. Nagaria, S. Tiwari
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New methodologies for XOR-XNOR circuits are proposed to improve the speed and power as these circuits are basic building blocks of many arithmetic circuits. This paper evaluates and compares the performance of various XOR-XNOR circuits. The performance of the XOR-XNOR circuits based on TSMC 0.18μm process models at all range of the supply voltage starting from 0.6V to 3.3V is evaluated by the comparison of the simulation results obtained from HSPICE. Simulation results reveal that the proposed circuit exhibit lower PDP and EDP, more power efficient and faster when compared with best available XOR-XNOR circuits in the literature.Keywords: Exclusive-OR (XOR), Exclusive-NOR (XNOR), High speed, Low power, Arithmetic Circuits.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 28411601 Numerical Simulation of the Flow Field around a 30° Inclined Flat Plate
Authors: M. Raciti Castelli, P. Cioppa, E. Benini
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This paper presents a CFD analysis of the flow around a 30° inclined flat plate of infinite span. Numerical predictions have been compared to experimental measurements, in order to assess the potential of the finite volume code of determining the aerodynamic forces acting on a flat plate invested by a fluid stream of infinite extent. Several turbulence models and spatial node distributions have been tested and flow field characteristics in the neighborhood of the flat plate have been numerically investigated, allowing the development of a preliminary procedure to be used as guidance in selecting the appropriate grid configuration and the corresponding turbulence model for the prediction of the flow field over a twodimensional inclined plate.Keywords: CFD, lift, drag, flat plate
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 33081600 Methodologies, Systems Development Life Cycle and Modeling Languages in Agile Software Development
Authors: I. D. Arroyo
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This article seeks to integrate different concepts from contemporary software engineering with an agile development approach. We seek to clarify some definitions and uses, we make a difference between the Systems Development Life Cycle (SDLC) and the methodologies, we differentiate the types of frameworks such as methodological, philosophical and behavioral, standards and documentation. We define relationships based on the documentation of the development process through formal and ad hoc models, and we define the usefulness of using DevOps and Agile Modeling as integrative methodologies of principles and best practices.Keywords: Methodologies, SDLC, modeling languages, agile modeling, DevOps, UML, agile software development.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 9451599 A Review on Important Aspects of Information Retrieval
Authors: Yogesh Gupta, Ashish Saini, A.K. Saxena
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Information retrieval has become an important field of study and research under computer science due to explosive growth of information available in the form of full text, hypertext, administrative text, directory, numeric or bibliographic text. The research work is going on various aspects of information retrieval systems so as to improve its efficiency and reliability. This paper presents a comprehensive study, which discusses not only emergence and evolution of information retrieval but also includes different information retrieval models and some important aspects such as document representation, similarity measure and query expansion.
Keywords: Information Retrieval, query expansion, similarity measure, query expansion, vector space model.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 33381598 Rapid Prototyping Applications in Various Field of Engineering and Technology
Authors: R. Kumaravelan, V. C. Sathish Gandhi, S. Ramesh, M. Venkatesan
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In the product design and development process, the prototyping or model making is one of the important step to finalize a product which helps in conceptualization of a design. Rapid Prototyping (RP) is layer-by-layer material deposition started during early 1980s with the enormous growth in Computer Aided Design and Manufacturing (CAD/CAM) technologies. The edges and surfaces of a complex solid model and their information are used for defining a product which is further manufactured as a finished product by CNC machining. This paper provides a better platform for researchers, new learners and product manufacturers for various applications of RP models. Subsequently it creates awareness among the peoples of recently developing RP method of manufacturing in product design, developments and its applications.
Keywords: Prototyping, layer-by-layer, CAD/CAM, product design.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 81741597 Brainwave Classification for Brain Balancing Index (BBI) via 3D EEG Model Using k-NN Technique
Authors: N. Fuad, M. N. Taib, R. Jailani, M. E. Marwan
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In this paper, the comparison between k-Nearest Neighbor (kNN) algorithms for classifying the 3D EEG model in brain balancing is presented. The EEG signal recording was conducted on 51 healthy subjects. Development of 3D EEG models involves pre-processing of raw EEG signals and construction of spectrogram images. Then, maximum PSD values were extracted as features from the model. There are three indexes for balanced brain; index 3, index 4 and index 5. There are significant different of the EEG signals due to the brain balancing index (BBI). Alpha-α (8–13 Hz) and beta-β (13–30 Hz) were used as input signals for the classification model. The k-NN classification result is 88.46% accuracy. These results proved that k-NN can be used in order to predict the brain balancing application.
Keywords: Brain balancing, kNN, power spectral density, 3D EEG model.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 26241596 Simulating Climate Change (Temperature and Soil Moisture) in a Mixed-Deciduous Forest, Ontario, Canada
Authors: David Goldblum, Lesley S. Rigg
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To simulate expected climate change, we implemented a two-factor (temperature and soil moisture) field design in a forest in Ontario, Canada. To manipulate moisture input, we erected rain-exclusion structures. Under each structure, plots were watered with one of three treatments and thermally controlled with three heat treatments to simulate changes in air temperature and rainfall based on the climate model (GCM) predictions for the study area. Environmental conditions (including untreated controls) were monitored tracking air temperature, soil temperature, soil moisture, and photosynthetically active radiation. We measured rainfall and relative humidity at the site outside the rain-exclusion structures. Analyses of environmental conditions demonstrates that the temperature manipulation was most effective at maintaining target temperature during the early part of the growing season, but it was more difficult to keep the warmest treatment at 5º C above ambient by late summer. Target moisture regimes were generally achieved however incoming solar radiation was slightly attenuated by the structures.
Keywords: Acer saccharum, climate change, forest, environmental manipulation.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 17261595 Prediction of Natural Gas Viscosity using Artificial Neural Network Approach
Authors: E. Nemati Lay, M. Peymani, E. Sanjari
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Prediction of viscosity of natural gas is an important parameter in the energy industries such as natural gas storage and transportation. In this study viscosity of different compositions of natural gas is modeled by using an artificial neural network (ANN) based on back-propagation method. A reliable database including more than 3841 experimental data of viscosity for testing and training of ANN is used. The designed neural network can predict the natural gas viscosity using pseudo-reduced pressure and pseudo-reduced temperature with AARD% of 0.221. The accuracy of designed ANN has been compared to other published empirical models. The comparison indicates that the proposed method can provide accurate results.
Keywords: Artificial neural network, Empirical correlation, Natural gas, Viscosity
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 32431594 Towards a Suitable and Systematic Approach for Component Based Software Development
Authors: Kuljit Kaur, Parminder Kaur, Jaspreet Bedi, Hardeep Singh
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Software crisis refers to the situation in which the developers are not able to complete the projects within time and budget constraints and moreover these overscheduled and over budget projects are of low quality as well. Several methodologies have been adopted form time to time to overcome this situation and now in the focus is component based software engineering. In this approach, emphasis is on reuse of already existing software artifacts. But the results can not be achieved just by preaching the principles; they need to be practiced as well. This paper highlights some of the very basic elements of this approach, which has to be in place to get the desired goals of high quality, low cost with shorter time-to-market software products.Keywords: Component Model, Software Components, SoftwareRepository, Process Models.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 17631593 A Study of Factors Influencing the Improvement of Technology Business Incubator's Effectiveness: An Explanatory Model
Authors: Alireza Ghasemizad
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In Both developed and developing countries, governments play a basic role in making policies, programs and instruments which support the development of micro, small and medium enterprises. One of the mechanisms employed to nurture small firms for more than two decades is business incubation. One of the mechanisms employed to nurture small firms for more than two decades is technology business incubation. The main aim of this research was to establish influencing factors in Technology Business Incubator's effectiveness and their explanatory model. Therefore, among 56 Technology Business Incubators in Iran, 32 active incubators were selected and by stratified random sampling, 528 start-ups were chosen. The validity of research questionnaires was determines by expert consensus, item analysis and factor analysis; and their reliability calculated by Cronbach-s alpha. Data analysis was then made through SPSS and LISREL soft wares. Both organizational procedures and entrepreneurial behaviors were the meaningful mediators. Organizational procedures with (P < .01, β =0.45) was stronger mediator for the improvement of Technology Business Incubator's effectiveness comparing to entrepreneurial behavior with (P < .01, β =0.36).Keywords: Technology, Incubators, Effectiveness, Explanatorymodel.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 20301592 Judges System for Classifiers Specialization
Authors: Abdel Rodríguez, Isis Bonet, Ricardo Grau, María M. García
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In this paper we designed and implemented a new ensemble of classifiers based on a sequence of classifiers which were specialized in regions of the training dataset where errors of its trained homologous are concentrated. In order to separate this regions, and to determine the aptitude of each classifier to properly respond to a new case, it was used another set of classifiers built hierarchically. We explored a selection based variant to combine the base classifiers. We validated this model with different base classifiers using 37 training datasets. It was carried out a statistical comparison of these models with the well known Bagging and Boosting, obtaining significantly superior results with the hierarchical ensemble using Multilayer Perceptron as base classifier. Therefore, we demonstrated the efficacy of the proposed ensemble, as well as its applicability to general problems.Keywords: classifiers, delegation, ensemble
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 13041591 A Review on Stormwater Harvesting and Reuse
Authors: Fatema Akram, Mohammad G. Rasul, M. Masud K. Khan, M. Sharif I. I. Amir
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Australia is a country of some 7,700 million square kilometers with a population of about 22.6 million. At present water security is a major challenge for Australia. In some areas the use of water resources is approaching and in some parts it is exceeding the limits of sustainability. A focal point of proposed national water conservation programs is the recycling of both urban stormwater and treated wastewater. But till now it is not widely practiced in Australia, and particularly stormwater is neglected. In Australia, only 4% of stormwater and rainwater is recycled, whereas less than 1% of reclaimed wastewater is reused within urban areas. Therefore, accurately monitoring, assessing and predicting the availability, quality and use of this precious resource are required for better management. As stormwater is usually of better quality than untreated sewage or industrial discharge, it has better public acceptance for recycling and reuse, particularly for non-potable use such as irrigation, watering lawns, gardens, etc. Existing stormwater recycling practice is far behind of research and no robust technologies developed for this purpose. Therefore, there is a clear need for using modern technologies for assessing feasibility of stormwater harvesting and reuse. Numerical modeling has, in recent times, become a popular tool for doing this job. It includes complex hydrological and hydraulic processes of the study area. The hydrologic model computes stormwater quantity to design the system components, and the hydraulic model helps to route the flow through stormwater infrastructures. Nowadays water quality module is incorporated with these models. Integration of Geographic Information System (GIS) with these models provides extra advantage of managing spatial information. However for the overall management of a stormwater harvesting project, Decision Support System (DSS) plays an important role incorporating database with model and GIS for the proper management of temporal information. Additionally DSS includes evaluation tools and Graphical user interface. This research aims to critically review and discuss all the aspects of stormwater harvesting and reuse such as available guidelines of stormwater harvesting and reuse, public acceptance of water reuse, the scopes and recommendation for future studies. In addition to these, this paper identifies, understand and address the importance of modern technologies capable of proper management of stormwater harvesting and reuse.
Keywords: Stormwater Management, Stormwater Harvesting and Reuse, Numerical Modeling, Geographic Information System (GIS), Decision Support System (DSS), Database.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 30551590 Numerical Simulation of Interfacial Flow with Volume-Of-Fluid Method
Authors: Afshin Ahmadi Nadooshan
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In this article, various models of surface tension force (CSF, CSS and PCIL) for interfacial flows have been applied to dynamic case and the results were compared. We studied the Kelvin- Helmholtz instabilities, which are produced by shear at the interface between two fluids with different physical properties. The velocity inlet is defined as a sinusoidal perturbation. When gravity and surface tension are taking into account, we observe the development of the Instability for a critic value of the difference of velocity of the both fluids. The VOF Model enables to simulate Kelvin-Helmholtz Instability as dynamic case.
Keywords: Interfacial flow, Incompressible flow, surface tension, Volume-Of-Fluid, Kelvin-Helmholtz.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 25601589 Rainfall–Runoff Simulation Using WetSpa Model in Golestan Dam Basin, Iran
Authors: M. R. Dahmardeh Ghaleno, M. Nohtani, S. Khaledi
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Flood simulation and prediction is one of the most active research areas in surface water management. WetSpa is a distributed, continuous, and physical model with daily or hourly time step that explains precipitation, runoff, and evapotranspiration processes for both simple and complex contexts. This model uses a modified rational method for runoff calculation. In this model, runoff is routed along the flow path using Diffusion-Wave equation which depends on the slope, velocity, and flow route characteristics. Golestan Dam Basin is located in Golestan province in Iran and it is passing over coordinates 55° 16´ 50" to 56° 4´ 25" E and 37° 19´ 39" to 37° 49´ 28"N. The area of the catchment is about 224 km2, and elevations in the catchment range from 414 to 2856 m at the outlet, with average slope of 29.78%. Results of the simulations show a good agreement between calculated and measured hydrographs at the outlet of the basin. Drawing upon Nash-Sutcliffe model efficiency coefficient for calibration periodic model estimated daily hydrographs and maximum flow rate with an accuracy up to 59% and 80.18%, respectively.
Keywords: Watershed simulation, WetSpa, stream flow, flood prediction.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 10311588 Investigation of SSR Characteristics of SSSC With GA Based Voltage Controller
Authors: R. Thirumalaivasan, M.Janaki, Nagesh Prabhu
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In this paper, investigation of subsynchronous resonance (SSR) characteristics of a hybrid series compensated system and the design of voltage controller for three level 24-pulse Voltage Source Converter based Static Synchronous Series Compensator (SSSC) is presented. Hybrid compensation consists of series fixed capacitor and SSSC which is a active series FACTS controller. The design of voltage controller for SSSC is based on damping torque analysis, and Genetic Algorithm (GA) is adopted for tuning the controller parameters. The SSR Characteristics of SSSC with constant reactive voltage control modes has been investigated. The results show that the constant reactive voltage control of SSSC has the effect of reducing the electrical resonance frequency, which detunes the SSR.The analysis of SSR with SSSC is carried out based on frequency domain method, eigenvalue analysis and transient simulation. While the eigenvalue and damping torque analysis are based on D-Q model of SSSC, the transient simulation considers both D-Q and detailed three phase nonlinear system model using switching functions.Keywords: FACTS, SSR, SSSC, damping torque, GA.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 17331587 A Discretizing Method for Reliability Computation in Complex Stress-strength Models
Authors: Alessandro Barbiero
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This paper proposes, implements and evaluates an original discretization method for continuous random variables, in order to estimate the reliability of systems for which stress and strength are defined as complex functions, and whose reliability is not derivable through analytic techniques. This method is compared to other two discretizing approaches appeared in literature, also through a comparative study involving four engineering applications. The results show that the proposal is very efficient in terms of closeness of the estimates to the true (simulated) reliability. In the study we analyzed both a normal and a non-normal distribution for the random variables: this method is theoretically suitable for each parametric family.
Keywords: Approximation, asymmetry, experimental design, interference theory, Monte Carlo simulations.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 17691586 GIS-based Approach for Land-Use Analysis: A Case Study
Authors: M. Giannopoulou, I. Roukounis, A. Roukouni.
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Geographical Information Systems are an integral part of planning in modern technical systems. Nowadays referred to as Spatial Decision Support Systems, as they allow synergy database management systems and models within a single user interface machine and they are important tools in spatial design for evaluating policies and programs at all levels of administration. This work refers to the creation of a Geographical Information System in the context of a broader research in the area of influence of an under construction station of the new metro in the Greek city of Thessaloniki, which included statistical and multivariate data analysis and diagrammatic representation, mapping and interpretation of the results.Keywords: Databases, Geographical information systems (GIS), Land-use planning, Metro stations
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 16021585 Photoimpedance Spectroscopy Analysis of Planar and Nano-Textured Thin-Film Silicon Solar Cells
Authors: P. Kumar, D. Eisenhauer, M. M. K. Yousef, Q. Shi, A. S. G. Khalil, M. R. Saber, C. Becker, T. Pullerits, K. J. Karki
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In impedance spectroscopy (IS) the response of a photo-active device is analysed as a function of ac bias. It is widely applied in a broad class of material systems and devices. It gives access to fundamental mechanisms of operation of solar cells. We have implemented a method of IS where we modulate the light instead of the bias. This scheme allows us to analyze not only carrier dynamics but also impedance of device locally. Here, using this scheme, we have measured the frequency-dependent photocurrent response of the thin-film planar and nano-textured Si solar cells using this method. Photocurrent response is measured in range of 50 Hz to 50 kHz. Bode and Nyquist plots are used to determine characteristic lifetime of both the cells. Interestingly, the carrier lifetime of both planar and nano-textured solar cells depend on back and front contact positions. This is due to either heterogeneity of device or contacts are not optimized. The estimated average lifetime is found to be shorter for the nano-textured cell, which could be due to the influence of the textured interface on the carrier relaxation dynamics.Keywords: Carrier lifetime, Impedance, nano-textured, and photocurrent.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 10271584 Low-complexity Integer Frequency Offset Synchronization for OFDMA System
Authors: Young-Jae Kim, Young-Hwan You
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This paper presents a integer frequency offset (IFO) estimation scheme for the 3GPP long term evolution (LTE) downlink system. Firstly, the conventional joint detection method for IFO and sector cell index (CID) information is introduced. Secondly, an IFO estimation without explicit sector CID information is proposed, which can operate jointly with the proposed IFO estimation and reduce the time delay in comparison with the conventional joint method. Also, the proposed method is computationally efficient and has almost similar performance in comparison with the conventional method over the Pedestrian and Vehicular channel models.Keywords: LTE, OFDMA, primary synchronization signal (PSS), IFO, CID
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 23121583 Bipolar PWM and LCL Filter Configuration to Reduce Leakage Currents in Transformerless PV System Connected to Utility Grid
Authors: Shanmuka Naga Raju
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This paper presents PV system without considering transformer connected to electric grid. This is considered more economic compared to present PV system. The problem that occurs when transformer is not considered appears with a leakage current near capacitor connected to ground. Bipolar Pulse Width Modulation (BPWM) technique along with filter L-C-L configuration in the circuit is modeled to shrink the leakage current in the circuit. The DC/AC inverter is modeled using H-bridge Insulated Gate Bipolar Transistor (IGBT) module which is controlled using proposed Bipolar PWM control technique. To extract maximum power, Maximum Power Point Technique (MPPT) controller is used in this model. Voltage and current regulators are used to determine the reference voltage for the inverter from active and reactive current where reactive current is set to zero. The PLL is modeled to synchronize the measurements. The model is designed with MATLAB Simulation blocks and compared with the methods available in literature survey to show its effectiveness.Keywords: Photovoltaic, PV, pulse width modulation, PWM, perturb and observe, phase locked loop.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 10181582 Combustion Analysis of Suspended Sodium Droplet
Authors: T. Watanabe
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Combustion analysis of suspended sodium droplet is performed by solving numerically the Navier-Stokes equations and the energy conservation equations. The combustion model consists of the pre-ignition and post-ignition models. The reaction rate for the pre-ignition model is based on the chemical kinetics, while that for the post-ignition model is based on the mass transfer rate of oxygen. The calculated droplet temperature is shown to be in good agreement with the existing experimental data. The temperature field in and around the droplet is obtained as well as the droplet shape variation, and the present numerical model is confirmed to be effective for the combustion analysis.
Keywords: Combustion, analysis, sodium, droplet.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 697