Search results for: Denison culture model
16301 The Utilization of FSI Technique and Two-Way Particle Coupling System on Particle Dynamics in the Human Alveoli
Authors: Hassan Athari, Abdurrahim Bolukbasi, Dogan Ciloglu
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This study represented the respiratory alveoli system, and determined the trajectory of inhaled particles more accurately using the modified three-dimensional model with deformable walls of alveoli. The study also considered the tissue tension in the model to demonstrate the effect of lung. Tissue tensions are transferred by the lung parenchyma and produce the pressure gradient. This load expands the alveoli and establishes a sub-ambient (vacuum) pressure within the lungs. Thus, at the alveolar level, the flow field and movement of alveoli wall lead to an integrated effect. In this research, we assume that the three-dimensional alveolus has a visco-elastic tissue (walls). For accurate investigation of pulmonary tissue mechanical properties on particle transport and alveolar flow field, the actual relevance between tissue movement and airflow is solved by two-way FSI (Fluid Structure Interaction) simulation technique in the alveolus. Therefore, the essence of real simulation of pulmonary breathing mechanics can be achieved by developing a coupled FSI computational model. We, therefore conduct a series of FSI simulations over a range of tissue models and breathing rates. As a result, the fluid flows and streamlines have changed during present flexible model against the rigid models and also the two-way coupling particle trajectories have changed against the one-way particle coupling.Keywords: FSI, two-way particle coupling, alveoli, CDF
Procedia PDF Downloads 26516300 Radial Basis Surrogate Model Integrated to Evolutionary Algorithm for Solving Computation Intensive Black-Box Problems
Authors: Abdulbaset Saad, Adel Younis, Zuomin Dong
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For design optimization with high-dimensional expensive problems, an effective and efficient optimization methodology is desired. This work proposes a series of modification to the Differential Evolution (DE) algorithm for solving computation Intensive Black-Box Problems. The proposed methodology is called Radial Basis Meta-Model Algorithm Assisted Differential Evolutionary (RBF-DE), which is a global optimization algorithm based on the meta-modeling techniques. A meta-modeling assisted DE is proposed to solve computationally expensive optimization problems. The Radial Basis Function (RBF) model is used as a surrogate model to approximate the expensive objective function, while DE employs a mechanism to dynamically select the best performing combination of parameters such as differential rate, cross over probability, and population size. The proposed algorithm is tested on benchmark functions and real life practical applications and problems. The test results demonstrate that the proposed algorithm is promising and performs well compared to other optimization algorithms. The proposed algorithm is capable of converging to acceptable and good solutions in terms of accuracy, number of evaluations, and time needed to converge.Keywords: differential evolution, engineering design, expensive computations, meta-modeling, radial basis function, optimization
Procedia PDF Downloads 40216299 Prediction of the Transmittance of Various Bended Angles Lightpipe by Using Neural Network under Different Sky Clearness Condition
Authors: Li Zhang, Yuehong Su
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Lightpipe as a mature solar light tube technique has been employed worldwide. Accurately assessing the performance of lightpipe and evaluate daylighting available has been a challenging topic. Previous research had used regression model and computational simulation methods to estimate the performance of lightpipe. However, due to the nonlinear nature of solar light transferring in lightpipe, the methods mentioned above express inaccurate and time-costing issues. In the present study, a neural network model as an alternative method is investigated to predict the transmittance of lightpipe. Four types of commercial lightpipe with bended angle 0°, 30°, 45° and 60° are discussed under clear, intermediate and overcast sky conditions respectively. The neural network is generated in MATLAB by using the outcomes of an optical software Photopia simulations as targets for networks training and testing. The coefficient of determination (R²) for each model is higher than 0.98, and the mean square error (MSE) is less than 0.0019, which indicate the neural network strong predictive ability and the use of the neural network method could be an efficient technique for determining the performance of lightpipe.Keywords: neural network, bended lightpipe, transmittance, Photopia
Procedia PDF Downloads 15616298 Modeling Influence on Petty Corruption Attitudes
Authors: Nina Bijedic, Drazena Gaspar, Mirsad Hadzikadic
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Corruption is an influential and widespread problem. One part of it is so-called petty corruption, related to large-scale bribe giving by ordinary citizens trying to influence the works of public administration or public services. As it is with all means of corruption, petty corruption is related to the level of democracy (or administration efficiency) in a society. The developed model captures some of the factors related to corruptive behavior, as well as people’s attitude towards petty corruption. It has four basic elements: user’s perception of corruption in the society of interest, the influence of social interactions, the influence of penalizing mechanism, and influence of campaigns against petty corruption. The model is agent-based, developed in NetLogo, with a lot of random settings that provide a wider scope of responses. Interactions of different settings for variables of elements provide insight into the influence of each element on attitude towards petty corruption, as well as petty corruptive behavior.Keywords: agent-based model, attitude, influence, petty corruption, society
Procedia PDF Downloads 20216297 Research of Intrinsic Emittance of Thermal Cathode with Emission Nonuniformity
Authors: Yufei Peng, Zhen Qin, Jianbe Li, Jidong Long
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The thermal cathode is widely used in accelerators, FELs and kinds of vacuum electronics. However, emission nonuniformity exists due to surface profile, material distribution, temperature variation, crystal orientation, etc., which will cause intrinsic emittance growth, brightness decline, envelope size augment, device performance deterioration or even failure. To understand how emittance is manipulated by emission nonuniformity, an intrinsic emittance model consisting of contributions from macro and micro surface nonuniformity is developed analytically based on general thermal emission model at temperature limited regime according to a real 3mm cathode. The model shows relative emittance increased about 50% due to temperature variation, and less than 5% from several kinds of micro surface nonuniformity which is much smaller than other research. Otherwise, we also calculated emittance growth combining with Monte Carlo method and PIC simulation, experiments of emission uniformity and emittance measurement are going to be carried out separately.Keywords: thermal cathode, electron emission fluctuation, intrinsic emittance, surface nonuniformity, cathode lifetime
Procedia PDF Downloads 30116296 Optimal Cropping Pattern in an Irrigation Project: A Hybrid Model of Artificial Neural Network and Modified Simplex Algorithm
Authors: Safayat Ali Shaikh
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Software has been developed for optimal cropping pattern in an irrigation project considering land constraint, water availability constraint and pick up flow constraint using modified Simplex Algorithm. Artificial Neural Network Models (ANN) have been developed to predict rainfall. AR (1) model used to generate 1000 years rainfall data to train the ANN. Simulation has been done with expected rainfall data. Eight number crops and three types of soil class have been considered for optimization model. Area under each crop and each soil class have been quantified using Modified Simplex Algorithm to get optimum net return. Efficacy of the software has been tested using data of large irrigation project in India.Keywords: artificial neural network, large irrigation project, modified simplex algorithm, optimal cropping pattern
Procedia PDF Downloads 20716295 Application of Forward Contract and Crop Insurance as Risk Management Tools of Agriculture: A Case Study in Bangladesh
Authors: M. Bokhtiar Hasan, M. Delowar Hossain, Abu N. M. Wahid
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The principal aim of the study is to find out a way to effectively manage the agricultural risks like price volatility, weather risks, and fund shortage. To hedge price volatility, farmers sometimes make contracts with agro-traders but fail to protect themselves effectively due to not having legal framework for such contracts. The study extensively reviews existing literature and find evidence that the majority studies either deal with price volatility or weather risks. If we could address these risks through a single model, it would be more useful to both the farmers and traders. Intrinsically, the authors endeavor in this regard, and the key contribution of this study basically lies in it. Initially, we conduct a small survey aspiring to identify the shortcomings of existing contracts. Later, we propose a model encompassing forward and insurance contracts together where forward contract will be used to hedge price volatility and insurance contract will be used to protect weather risks. Contribution/Originality: The study adds to the existing literature through proposing an integrated model comprising of forward contract and crop insurance which will support both farmers and traders to cope with the agricultural risks like price volatility, weather hazards, and fund shortage. JEL Classifications: O13, Q13Keywords: agriculture, forward contract, insurance contract, risk management, model
Procedia PDF Downloads 15916294 Inversion of PROSPECT+SAIL Model for Estimating Vegetation Parameters from Hyperspectral Measurements with Application to Drought-Induced Impacts Detection
Authors: Bagher Bayat, Wouter Verhoef, Behnaz Arabi, Christiaan Van der Tol
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The aim of this study was to follow the canopy reflectance patterns in response to soil water deficit and to detect trends of changes in biophysical and biochemical parameters of grass (Poa pratensis species). We used visual interpretation, imaging spectroscopy and radiative transfer model inversion to monitor the gradual manifestation of water stress effects in a laboratory setting. Plots of 21 cm x 14.5 cm surface area with Poa pratensis plants that formed a closed canopy were subjected to water stress for 50 days. In a regular weekly schedule, canopy reflectance was measured. In addition, Leaf Area Index (LAI), Chlorophyll (a+b) content (Cab) and Leaf Water Content (Cw) were measured at regular time intervals. The 1-D bidirectional canopy reflectance model SAIL, coupled with the leaf optical properties model PROSPECT, was inverted using hyperspectral measurements by means of an iterative optimization method to retrieve vegetation biophysical and biochemical parameters. The relationships between retrieved LAI, Cab, Cw, and Cs (Senescent material) with soil moisture content were established in two separated groups; stress and non-stressed. To differentiate the water stress condition from the non-stressed condition, a threshold was defined that was based on the laboratory produced Soil Water Characteristic (SWC) curve. All parameters retrieved by model inversion using canopy spectral data showed good correlation with soil water content in the water stress condition. These parameters co-varied with soil moisture content under the stress condition (Chl: R2= 0.91, Cw: R2= 0.97, Cs: R2= 0.88 and LAI: R2=0.48) at the canopy level. To validate the results, the relationship between vegetation parameters that were measured in the laboratory and soil moisture content was established. The results were totally in agreement with the modeling outputs and confirmed the results produced by radiative transfer model inversion and spectroscopy. Since water stress changes all parts of the spectrum, we concluded that analysis of the reflectance spectrum in the VIS-NIR-MIR region is a promising tool for monitoring water stress impacts on vegetation.Keywords: hyperspectral remote sensing, model inversion, vegetation responses, water stress
Procedia PDF Downloads 22616293 Numerical Simulation on Deformation Behaviour of Additively Manufactured AlSi10Mg Alloy
Authors: Racholsan Raj Nirmal, B. S. V. Patnaik, R. Jayaganthan
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The deformation behaviour of additively manufactured AlSi10Mg alloy under low strains, high strain rates and elevated temperature conditions is essential to analyse and predict its response against dynamic loading such as impact and thermomechanical fatigue. The constitutive relation of Johnson-Cook is used to capture the strain rate sensitivity and thermal softening effect in AlSi10Mg alloy. Johnson-Cook failure model is widely used for exploring damage mechanics and predicting the fracture in many materials. In this present work, Johnson-Cook material and damage model parameters for additively manufactured AlSi10Mg alloy have been determined numerically from four types of uniaxial tensile test. Three different uniaxial tensile tests with dynamic strain rates (0.1, 1, 10, 50, and 100 s-1) and elevated temperature tensile test with three different temperature conditions (450 K, 500 K and 550 K) were performed on 3D printed AlSi10Mg alloy in ABAQUS/Explicit. Hexahedral elements are used to discretize tensile specimens and fracture energy value of 43.6 kN/m was used for damage initiation. Levenberg Marquardt optimization method was used for the evaluation of Johnson-Cook model parameters. It was observed that additively manufactured AlSi10Mg alloy has shown relatively higher strain rate sensitivity and lower thermal stability as compared to the other Al alloys.Keywords: ABAQUS, additive manufacturing, AlSi10Mg, Johnson-Cook model
Procedia PDF Downloads 17416292 Development of an Optimised, Automated Multidimensional Model for Supply Chains
Authors: Safaa H. Sindi, Michael Roe
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This project divides supply chain (SC) models into seven Eras, according to the evolution of the market’s needs throughout time. The five earliest Eras describe the emergence of supply chains, while the last two Eras are to be created. Research objectives: The aim is to generate the two latest Eras with their respective models that focus on the consumable goods. Era Six contains the Optimal Multidimensional Matrix (OMM) that incorporates most characteristics of the SC and allocates them into four quarters (Agile, Lean, Leagile, and Basic SC). This will help companies, especially (SMEs) plan their optimal SC route. Era Seven creates an Automated Multidimensional Model (AMM) which upgrades the matrix of Era six, as it accounts for all the supply chain factors (i.e. Offshoring, sourcing, risk) into an interactive system with Heuristic Learning that helps larger companies and industries to select the best SC model for their market. Methodologies: The data collection is based on a Fuzzy-Delphi study that analyses statements using Fuzzy Logic. The first round of Delphi study will contain statements (fuzzy rules) about the matrix of Era six. The second round of Delphi contains the feedback given from the first round and so on. Preliminary findings: both models are applicable, Matrix of Era six reduces the complexity of choosing the best SC model for SMEs by helping them identify the best strategy of Basic SC, Lean, Agile and Leagile SC; that’s tailored to their needs. The interactive heuristic learning in the AMM of Era seven will help mitigate error and aid large companies to identify and re-strategize the best SC model and distribution system for their market and commodity, hence increasing efficiency. Potential contributions to the literature: The problematic issue facing many companies is to decide which SC model or strategy to incorporate, due to the many models and definitions developed over the years. This research simplifies this by putting most definition in a template and most models in the Matrix of era six. This research is original as the division of SC into Eras, the Matrix of Era six (OMM) with Fuzzy-Delphi and Heuristic Learning in the AMM of Era seven provides a synergy of tools that were not combined before in the area of SC. Additionally the OMM of Era six is unique as it combines most characteristics of the SC, which is an original concept in itself.Keywords: Leagile, automation, heuristic learning, supply chain models
Procedia PDF Downloads 39616291 An Assessment of Potentials, Challenges, and Opportunities of Ethiopian Cultural Centers for Tourism Product Development
Authors: Berie Abebe Getahun
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The tourism sector has been identified by the Ethiopian government as one of the priority economic sectors and planned to make Ethiopia among the top five African destinations by 2020. It is obvious international tourism demand for Ethiopia lags behind other African countries like South Africa, Egypt, Morocco, Tanzania, and Kenya. Meanwhile, the number of international tourists’ arrival to Ethiopia increases continuously. The main purpose of this study was to find out potentials, challenges, and opportunities of Ethiopian Cultural Center for tourism product development. Therefore, an attempt has been made to identify potentials over which tourism product development can be enhanced, and opportunities that promote tourism product development in Ethiopia. To achieve this objective, data have been collected by using observation, interview and focus group discussion with selected informants working the ministry of tourism and culture. The collected data has been analyzed by transcribing materials, and by using thematic analysis method based on the research objective. Likewise, the analyzed data has been discussed in the context of prevailing literature. As revealed in finding, Ethiopian cultural center has untapped potential for tourism product development that includes: meetings, incentives, conferences, events, availability of concerned stakeholders and demand of visitors. On the other hand, lack of awareness about tourism product development, financial constraints, skilled manpower, absence of tour guiding service and interpretation of heritages have been identified as the major challenges that hindering tourism product development in the cultural center. Moreover, the growth of domestic tourism, distinctive presence and rich culture of Ethiopia, and policy of Ethiopia that promotes the growth and preservation of indigenous cultures are deemed important opportunities for tourism product development in the country. And lastly, conducting a research based on tourism product development, reviewing the existing marketing and promotion strategies, training manpower, working harmoniously with the concerned stakeholders, and a careful examination of opportunities present in order to best utilize resources were implications drawn for future intervention.Keywords: challenges and opportunities of tourism, Ethiopian tourism potential, tourism product, tourism product development
Procedia PDF Downloads 16616290 Translation and Transculturality in Contemporary Chinese Art: A Case Study of Gu Wenda’s 'Forest of Stone Steles' and 'United Nations: Temple of Heaven'
Authors: Rui Zhang
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Translation has been elevated to one of the key notions in contemporary cultural discourse for a wide range of fields. It focuses not only on communication or transmission of meaning between different languages, but also on ways in which the very act of translation can be understood as a metaphor for cultural process. In recent years, the notion of translation is employed by some contemporary Chinese artists in a conceptual way, whose works contribute to constructing/deconstructing global/local cultural discourse and their own cultural identities. This study examines two artworks by contemporary Chinese artist Gu Wenda from a translational perspective, namely Forest of Stone Steles - Retranslation & Rewriting of Tang Poetry and United Nations - China Monument: Temple of Heaven, aiming to broaden the scope of Translation Studies to investigate visual culture and enrich methodological approach to contemporary Chinese art. Focusing on the relationship between translation, visuality and materiality in these two works, this study explores the nature of translation as part of the production of cultural discourse in the age of globalization as well as a way of establishing cultural identity. Gu Wenda, one of the most prestigious artists in contemporary China, is considered a pioneer in ‘85 Art Movement of China, and thereafter he went abroad for his artistic pursuits. His transnational experience enriches his cultural identity and the underlying discourse constructed/deconstructed in many of his works. In the two works already mentioned, the concept of translation is deployed by Gu Wenda on both linguistic level and metaphorical level for artistic expression. These two works produce discourses in which the artist’s perception of cultural identity in a transnational context is articulated by the tension between source text and target text. Based on the conceptual framework of cultural identity proposed by Stuart Hall, analyses of Gu Wenda’s cultural identity revealed through translation in these two works are centred on two axes, i.e., the axis of similarity and continuity with Chinese intellectual culture and the axis of difference and rupture with it, and the dialogic relationship between these two vectors. It argues that besides serving as a means of constructing visuality in the two works, translation metaphorizes Gu Wenda’s journey from overcoming his cultural identity anxiety to re-establishing a transcultural identity embedded in the underlying discourse.Keywords: contemporary Chinese art, cultural identity, transculturality, translation
Procedia PDF Downloads 50016289 Modeling Child Development Factors for the Early Introduction of ICTs in Schools
Authors: K. E. Oyetade, S. D. Eyono Obono
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One of the fundamental characteristics of Information and Communication Technology (ICT) has been the ever-changing nature of continuous release and models of ICTs with its impact on the academic, social, and psychological benefits of its introduction in schools. However, there seems to be a growing concern about its negative impact on students when introduced early in schools for teaching and learning. This study aims to design a model of child development factors affecting the early introduction of ICTs in schools in an attempt to improve the understanding of child development and introduction of ICTs in schools. The proposed model is based on a sound theoretical framework. It was designed following a literature review of child development theories and child development factors. The child development theoretical framework that fitted to the best of all child development factors was then chosen as the basis for the proposed model. This study hence found that the Jean Piaget cognitive developmental theory is the most adequate theoretical frameworks for modeling child development factors for ICT introduction in schools.Keywords: child development factors, child development theories, ICTs, theory
Procedia PDF Downloads 41716288 Transformation of the Business Model in an Occupational Health Care Company Embedded in an Emerging Personal Data Ecosystem: A Case Study in Finland
Authors: Tero Huhtala, Minna Pikkarainen, Saila Saraniemi
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Information technology has long been used as an enabler of exchange for goods and services. Services are evolving from generic to personalized, and the reverse use of customer data has been discussed in both academia and industry for the past few years. This article presents the results of an empirical case study in the area of preventive health care services. The primary data were gathered in workshops, in which future personal data-based services were conceptualized by analyzing future scenarios from a business perspective. The aim of this study is to understand business model transformation in emerging personal data ecosystems. The work was done as a case study in the context of occupational healthcare. The results have implications to theory and practice, indicating that adopting personal data management principles requires transformation of the business model, which, if successfully managed, may provide access to more resources, potential to offer better value, and additional customer channels. These advantages correlate with the broadening of the business ecosystem. Expanding the scope of this study to include more actors would improve the validity of the research. The results draw from existing literature and are based on findings from a case study and the economic properties of the healthcare industry in Finland.Keywords: ecosystem, business model, personal data, preventive healthcare
Procedia PDF Downloads 25516287 Dynamic Process Monitoring of an Ammonia Synthesis Fixed-Bed Reactor
Authors: Bothinah Altaf, Gary Montague, Elaine B. Martin
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This study involves the modeling and monitoring of an ammonia synthesis fixed-bed reactor using partial least squares (PLS) and its variants. The process exhibits complex dynamic behavior due to the presence of heat recycling and feed quench. One limitation of static PLS model in this situation is that it does not take account of the process dynamics and hence dynamic PLS was used. Although it showed, superior performance to static PLS in terms of prediction, the monitoring scheme was inappropriate hence adaptive PLS was considered. A limitation of adaptive PLS is that non-conforming observations also contribute to the model, therefore, a new adaptive approach was developed, robust adaptive dynamic PLS. This approach updates a dynamic PLS model and is robust to non-representative data. The developed methodology showed a clear improvement over existing approaches in terms of the modeling of the reactor and the detection of faults.Keywords: ammonia synthesis fixed-bed reactor, dynamic partial least squares modeling, recursive partial least squares, robust modeling
Procedia PDF Downloads 39516286 Simulation of a Cost Model Response Requests for Replication in Data Grid Environment
Authors: Kaddi Mohammed, A. Benatiallah, D. Benatiallah
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Data grid is a technology that has full emergence of new challenges, such as the heterogeneity and availability of various resources and geographically distributed, fast data access, minimizing latency and fault tolerance. Researchers interested in this technology address the problems of the various systems related to the industry such as task scheduling, load balancing and replication. The latter is an effective solution to achieve good performance in terms of data access and grid resources and better availability of data cost. In a system with duplication, a coherence protocol is used to impose some degree of synchronization between the various copies and impose some order on updates. In this project, we present an approach for placing replicas to minimize the cost of response of requests to read or write, and we implement our model in a simulation environment. The placement techniques are based on a cost model which depends on several factors, such as bandwidth, data size and storage nodes.Keywords: response time, query, consistency, bandwidth, storage capacity, CERN
Procedia PDF Downloads 27616285 Intellectual Property and SMEs in the Baltic Sea Region: A Comparative Study on the Use of the Utility Model Protection
Authors: Christina Wainikka, Besrat Tesfaye
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Several of the countries in the Baltic Sea region are ranked high in international innovations rankings, such as the Global Innovation Index and European Innovation Scoreboard. There are however some concerns in the performance of different countries. For example, there is a widely spread notion about “The Swedish Paradox”. Sweden is ranked high due to investments in R&D and patent activity, but the outcome is not as high as could be expected. SMEs in Sweden are also below EU average when it comes to registering intellectual property rights such as patents and trademarks. This study is concentrating on the protection of utility model. This intellectual property right does not exist in Sweden, but in for example Finland and Germany. The utility model protection is sometimes referred to as a “patent light” since it is easier to obtain than the patent protection but at the same time does cover technical solutions. In examining statistics on patent activities and activities in registering utility models it is clear that utility model protection is scarcely used in the countries that have the protection. In Germany 10 577 applications were made in 2021. In Finland there were 259 applications made in 2021. This can be compared with patent applications that were 58 568 in Germany in 2021 and 1 662 in Finland in 2021. In Sweden there has never been a protection for utility models. The only protection for technical solutions is patents and business secrets. The threshold for obtaining a patent is high, due to the legal requirements and the costs. The patent protection is there for often not chosen by SMEs in Sweden. This study examines whether the protection of utility models in other countries in the Baltic region provide SMEs in these countries with better options to protect their innovations. The legal methodology is comparative law. In order to study the effects of the legal differences statistics are examined and interviews done with SMEs from different industries.Keywords: baltic sea region, comparative law, SME, utility model
Procedia PDF Downloads 11916284 Componential Analysis on Defining Sustainable Furniture in Traditional Malay Houses of Melaka
Authors: Nabilah Zainal Abidin, Fawazul Khair Ibrahim, Raja Nafida Raja Shahminan
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This paper discusses on how componential analysis is used in architecture, mainly in determining the absence and presence of furniture in Traditional Malay Houses. The house samples were retrieved from the reports archived by the Centre of Built Environment in the Malay World (KALAM) of Universiti Teknologi Malaysia (UTM). Findings from the analysis indicate that furniture available in the spaces of the houses is determined by the culture of the people and the availability of certain furniture is influenced by the activities that are carried out within the space.Keywords: componential analysis, sustainable furniture, traditional malay house
Procedia PDF Downloads 59816283 An Improved Single Point Closure Model Based on Dissipation Anisotropy for Geophysical Turbulent Flows
Authors: A. P. Joshi, H. V. Warrior, J. P. Panda
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This paper is a continuation of the work carried out by various turbulence modelers in Oceanography on the topic of oceanic turbulent mixing. It evaluates the evolution of ocean water temperature and salinity by the appropriate modeling of turbulent mixing utilizing proper prescription of eddy viscosity. Many modelers in past have suggested including terms like shear, buoyancy and vorticity to be the parameters that decide the slow pressure strain correlation. We add to it the fact that dissipation anisotropy also modifies the correlation through eddy viscosity parameterization. This recalibrates the established correlation constants slightly and gives improved results. This anisotropization of dissipation implies that the critical Richardson’s number increases much beyond unity (to 1.66) to accommodate enhanced mixing, as is seen in reality. The model is run for a couple of test cases in the General Ocean Turbulence Model (GOTM) and the results are presented here.Keywords: Anisotropy, GOTM, pressure-strain correlation, Richardson critical number
Procedia PDF Downloads 16916282 Model-Driven and Data-Driven Approaches for Crop Yield Prediction: Analysis and Comparison
Authors: Xiangtuo Chen, Paul-Henry Cournéde
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Crop yield prediction is a paramount issue in agriculture. The main idea of this paper is to find out efficient way to predict the yield of corn based meteorological records. The prediction models used in this paper can be classified into model-driven approaches and data-driven approaches, according to the different modeling methodologies. The model-driven approaches are based on crop mechanistic modeling. They describe crop growth in interaction with their environment as dynamical systems. But the calibration process of the dynamic system comes up with much difficulty, because it turns out to be a multidimensional non-convex optimization problem. An original contribution of this paper is to propose a statistical methodology, Multi-Scenarios Parameters Estimation (MSPE), for the parametrization of potentially complex mechanistic models from a new type of datasets (climatic data, final yield in many situations). It is tested with CORNFLO, a crop model for maize growth. On the other hand, the data-driven approach for yield prediction is free of the complex biophysical process. But it has some strict requirements about the dataset. A second contribution of the paper is the comparison of these model-driven methods with classical data-driven methods. For this purpose, we consider two classes of regression methods, methods derived from linear regression (Ridge and Lasso Regression, Principal Components Regression or Partial Least Squares Regression) and machine learning methods (Random Forest, k-Nearest Neighbor, Artificial Neural Network and SVM regression). The dataset consists of 720 records of corn yield at county scale provided by the United States Department of Agriculture (USDA) and the associated climatic data. A 5-folds cross-validation process and two accuracy metrics: root mean square error of prediction(RMSEP), mean absolute error of prediction(MAEP) were used to evaluate the crop prediction capacity. The results show that among the data-driven approaches, Random Forest is the most robust and generally achieves the best prediction error (MAEP 4.27%). It also outperforms our model-driven approach (MAEP 6.11%). However, the method to calibrate the mechanistic model from dataset easy to access offers several side-perspectives. The mechanistic model can potentially help to underline the stresses suffered by the crop or to identify the biological parameters of interest for breeding purposes. For this reason, an interesting perspective is to combine these two types of approaches.Keywords: crop yield prediction, crop model, sensitivity analysis, paramater estimation, particle swarm optimization, random forest
Procedia PDF Downloads 23516281 Load Forecast of the Peak Demand Based on Both the Peak Demand and Its Location
Authors: Qais H. Alsafasfeh
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The aim of this paper is to provide a forecast of the peak demand for the next 15 years for electrical distribution companies. The proposed methodology provides both the peak demand and its location for the next 15 years. This paper describes the Spatial Load Forecasting model used, the information provided by electrical distribution company in Jordan, the workflow followed, the parameters used and the assumptions made to run the model. The aim of this paper is to provide a forecast of the peak demand for the next 15 years for electrical distribution companies. The proposed methodology provides both the peak demand and its location for the next 15 years. This paper describes the Spatial Load Forecasting model used, the information provided by electrical distribution company in Jordan, the workflow followed, the parameters used and the assumptions made to run the model.Keywords: load forecast, peak demand, spatial load, electrical distribution
Procedia PDF Downloads 49916280 An Extended Model for Sustainable Food and Nutrition Security in the Agrifood Sector
Authors: Ioannis Manikas
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The increased consumer demand for environmentally friendly production and distribution practices and the stricter environmental regulations turned environmental aspects into important criteria in business decision-making. On the other hand, Food and Nutrition Security (FNS) has evolved dramatically during the last decades in theory and practice serving as a reference point for exchanging experiences among all agents involved in programs and projects to fostering policy and strategy development. Global pressures make it more important than ever to gain a better understanding of the contribution that agrifood businesses make to FNS and to examine ways to make them more resilient in an increasingly globalized and uncertain world. This study extends the standard three-dimensional model of sustainability to include two more dimensions: A technological dimension and a policy/political dimension. Apart from the economic, environmental and social dimensions regularly used in sustainability literature, the extended model will accurately represent the measures and policies addressing food and nutrition security.Keywords: food and nutrition security, sustainability, food safety, resilience
Procedia PDF Downloads 34316279 Investigation on Mesh Sensitivity of a Transient Model for Nozzle Clogging
Authors: H. Barati, M. Wu, A. Kharicha, A. Ludwig
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A transient model for nozzle clogging has been developed and successfully validated against a laboratory experiment. Key steps of clogging are considered: transport of particles by turbulent flow towards the nozzle wall; interactions between fluid flow and nozzle wall, and the adhesion of the particle on the wall; the growth of the clog layer and its interaction with the flow. The current paper is to investigate the mesh (size and type) sensitivity of the model in both two and three dimensions. It is found that the algorithm for clog growth alone excluding the flow effect is insensitive to the mesh type and size, but the calculation including flow becomes sensitive to the mesh quality. The use of 2D meshes leads to overestimation of the clog growth because the 3D nature of flow in the boundary layer cannot be properly solved by 2D calculation. 3D simulation with tetrahedron mesh can also lead to an error estimation of the clog growth. A mesh-independent result can be achieved with hexahedral mesh, or at least with triangular prism (inflation layer) for near-wall regions.Keywords: clogging, continuous casting, inclusion, simulation, submerged entry nozzle
Procedia PDF Downloads 28716278 Establishment and Application of Numerical Simulation Model for Shot Peen Forming Stress Field Method
Authors: Shuo Tian, Xuepiao Bai, Jianqin Shang, Pengtao Gai, Yuansong Zeng
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Shot peen forming is an essential forming process for aircraft metal wing panel. With the development of computer simulation technology, scholars have proposed a numerical simulation method of shot peen forming based on stress field. Three shot peen forming indexes of crater diameter, shot speed and surface coverage are required as simulation parameters in the stress field method. It is necessary to establish the relationship between simulation and experimental process parameters in order to simulate the deformation under different shot peen forming parameters. The shot peen forming tests of the 2024-T351 aluminum alloy workpieces were carried out using uniform test design method, and three factors of air pressure, feed rate and shot flow were selected. The second-order response surface model between simulation parameters and uniform test factors was established by stepwise regression method using MATLAB software according to the results. The response surface model was combined with the stress field method to simulate the shot peen forming deformation of the workpiece. Compared with the experimental results, the simulated values were smaller than the corresponding test values, the maximum and average errors were 14.8% and 9%, respectively.Keywords: shot peen forming, process parameter, response surface model, numerical simulation
Procedia PDF Downloads 9416277 Evaluating the Use of Digital Art Tools for Drawing to Enhance Artistic Ability and Improve Digital Skill among Junior School Students
Authors: Aber Salem Aboalgasm, Rupert Ward
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This study investigated some results of the use of digital art tools by junior school children in order to discover if these tools could promote artistic ability and creativity. The study considers the ease of use and usefulness of the tools as well as how to assess artwork produced by digital means. As the use of these tools is a relatively new development in Art education, this study may help educators in their choice of which tools to use and when to use them. The study also aims to present a model for the assessment of students’ artistic development and creativity by studying their artistic activity. This model can help in determining differences in students’ creative ability and could be useful both for teachers, as a means of assessing digital artwork, and for students, by providing the motivation to use the tools to their fullest extent. Sixteen students aged nine to ten years old were observed and recorded while they used the digital drawing tools. The study found that, according to the students’ own statements, it was not the ease of use but the successful effects the tools provided which motivated the children to use them.Keywords: artistic ability, creativity, drawing digital tool, TAM model, psychomotor domain
Procedia PDF Downloads 33216276 Modelling Phytoremediation Rates of Aquatic Macrophytes in Aquaculture Effluent
Authors: E. A. Kiridi, A. O. Ogunlela
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Pollutants from aquacultural practices constitute environmental problems and phytoremediation could offer cheaper environmentally sustainable alternative since equipment using advanced treatment for fish tank effluent is expensive to import, install, operate and maintain, especially in developing countries. The main objective of this research was, therefore, to develop a mathematical model for phytoremediation by aquatic plants in aquaculture wastewater. Other objectives were to evaluate the retention times on phytoremediation rates using the model and to measure the nutrient level of the aquaculture effluent and phytoremediation rates of three aquatic macrophytes, namely; water hyacinth (Eichornia crassippes), water lettuce (Pistial stratoites) and morning glory (Ipomea asarifolia). A completely randomized experimental design was used in the study. Approximately 100 g of each macrophyte were introduced into the hydroponic units and phytoremediation indices monitored at 8 different intervals from the first to the 28th day. The water quality parameters measured were pH and electrical conductivity (EC). Others were concentration of ammonium–nitrogen (NH₄⁺ -N), nitrite- nitrogen (NO₂⁻ -N), nitrate- nitrogen (NO₃⁻ -N), phosphate –phosphorus (PO₄³⁻ -P), and biomass value. The biomass produced by water hyacinth was 438.2 g, 600.7 g, 688.2 g and 725.7 g at four 7–day intervals. The corresponding values for water lettuce were 361.2 g, 498.7 g, 561.2 g and 623.7 g and for morning glory were 417.0 g, 567.0 g, 642.0 g and 679.5g. Coefficient of determination was greater than 80% for EC, TDS, NO₂⁻ -N, NO₃⁻ -N and 70% for NH₄⁺ -N using any of the macrophytes and the predicted values were within the 95% confidence interval of measured values. Therefore, the model is valuable in the design and operation of phytoremediation systems for aquaculture effluent.Keywords: aquaculture effluent, macrophytes, mathematical model, phytoremediation
Procedia PDF Downloads 23016275 Assessing the Cumulative Impact of PM₂.₅ Emissions from Power Plants by Using the Hybrid Air Quality Model and Evaluating the Contributing Salient Factor in South Taiwan
Authors: Jackson Simon Lusagalika, Lai Hsin-Chih, Dai Yu-Tung
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Particles with an aerodynamic diameter of 2.5 meters or less are referred to as "fine particulate matter" (PM₂.₅) are easily inhaled and can go deeper into the lungs than other particles in the atmosphere, where it may have detrimental health consequences. In this study, we use a hybrid model that combined CMAQ and AERMOD as well as initial meteorological fields from the Weather Research and Forecasting (WRF) model to study the impact of power plant PM₂.₅ emissions in South Taiwan since it frequently experiences higher PM₂.₅ levels. A specific date of March 3, 2022, was chosen as a result of a power outage that prompted the bulk of power plants to shut down. In some way, it is not conceivable anywhere in the world to turn off the power for the sole purpose of doing research. Therefore, this catastrophe involving a power outage and the shutdown of power plants offers a great occasion to evaluate the impact of air pollution driven by this power sector. As a result, four numerical experiments were conducted in the study using the Continuous Emission Data System (CEMS), assuming that the power plants continued to function normally after the power outage. The hybrid model results revealed that power plants have a minor impact in the study region. However, we examined the accumulation of PM₂.₅ in the study and discovered that once the vortex at 925hPa was established and moved to the north of Taiwan's coast, the study region experienced higher observed PM₂.₅ concentrations influenced by meteorological factors. This study recommends that decision-makers take into account not only control techniques, specifically emission reductions, but also the atmospheric and meteorological implications for future investigations.Keywords: PM₂.₅ concentration, powerplants, hybrid air quality model, CEMS, Vorticity
Procedia PDF Downloads 7916274 Georgiana G. King’s The Way of Saint James. A Pioneer Cultural Guide of a Pilgrimage Route
Authors: Paula Pita-Galán
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In 1920 Georgiana Goddard King, an Art Historian and Professor at Bryn Mawr College (PA, USA), published The Way of Saint James (New York: P.G. Putnam’s Sons), one of the earliest modern guides of this pilgrimage route. In its three volumes, the author described the towns and villages crossed by the Camino, talking about the history, traditions, monuments, and the people that she had met during her own pilgrimage together with the photographer Edith H. Lowber. The two women walked the route from Toulouse to Santiago in several journeys that took place between 1911 and 1914, travelling with funds of the Hispanic Society of New York. The cultural interest that motivated the journey explains how King intertwines in her narration history, anthropology, geography, art history, and religion, giving; as a result, the book targeted intellectuals, curious travelers, and tourist rather than pilgrims in a moment in which the pilgrimage to Santiago had almost disappeared as a practice. The Way of Saint James is barely known nowadays, so the aim of this research is disseminate it, focusing on the modernity of its approach and pointing at the link that it has with Georgiana King’s understanding of art as a product of the culture and civilization that produces it. In this paper, we will analyze The Way of Saint James in its historiographical context as it was written during the rise of the interest on Spain and its culture in the United States of America; paying special attention on the relationship of the author with the Hispanic Society and sir Archer Milton Huntington. On the other hand, we will look into Georgiana Goddard King’s work as an scholar by analyzing her works and the personal papers (letters, notes, and manuscripts) that she left in Bryn Mawr College, where I have been researching with a Fulbright grant. As a result, we will understand the pioneer approach of this unique guide of the Way of Saint James as a reflection of Georgiana King’s own modernity as an scholar. The wide cultural interests of King gave, as a result, a guide that offers a transversal knowledge of The Way of Saint James, together with King’s impressions and experiences, in the same way of current guides but far from the ‘objective’ and formalist methodology followed by her colleagues. This kind of modernity was badly understood at her time and helped the oblivion of this book as well as her author.Keywords: georgiana goddard king, the way of saint james, pilgrimage, cultural heritage, guide
Procedia PDF Downloads 13516273 Dynamic Thermal Modelling of a PEMFC-Type Fuel Cell
Authors: Marco Avila Lopez, Hasnae Ait-Douchi, Silvia De Los Santos, Badr Eddine Lebrouhi, Pamela Ramírez Vidal
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In the context of the energy transition, fuel cell technology has emerged as a solution for harnessing hydrogen energy and mitigating greenhouse gas emissions. An in-depth study was conducted on a PEMFC-type fuel cell, with an initiation of an analysis of its operational principles and constituent components. Subsequently, the modelling of the fuel cell was undertaken using the Python programming language, encompassing both steady-state and transient regimes. In the case of the steady-state regime, the physical and electrochemical phenomena occurring within the fuel cell were modelled, with the assumption of uniform temperature throughout all cell compartments. Parametric identification was carried out, resulting in a remarkable mean error of only 1.62% when the model results were compared to experimental data documented in the literature. The dynamic model that was developed enabled the scrutiny of the fuel cell's response in terms of temperature and voltage under varying current conditions.Keywords: fuel cell, modelling, dynamic, thermal model, PEMFC
Procedia PDF Downloads 8516272 Interpretable Deep Learning Models for Medical Condition Identification
Authors: Dongping Fang, Lian Duan, Xiaojing Yuan, Mike Xu, Allyn Klunder, Kevin Tan, Suiting Cao, Yeqing Ji
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Accurate prediction of a medical condition with straight clinical evidence is a long-sought topic in the medical management and health insurance field. Although great progress has been made with machine learning algorithms, the medical community is still, to a certain degree, suspicious about the model's accuracy and interpretability. This paper presents an innovative hierarchical attention deep learning model to achieve good prediction and clear interpretability that can be easily understood by medical professionals. This deep learning model uses a hierarchical attention structure that matches naturally with the medical history data structure and reflects the member’s encounter (date of service) sequence. The model attention structure consists of 3 levels: (1) attention on the medical code types (diagnosis codes, procedure codes, lab test results, and prescription drugs), (2) attention on the sequential medical encounters within a type, (3) attention on the medical codes within an encounter and type. This model is applied to predict the occurrence of stage 3 chronic kidney disease (CKD3), using three years’ medical history of Medicare Advantage (MA) members from a top health insurance company. The model takes members’ medical events, both claims and electronic medical record (EMR) data, as input, makes a prediction of CKD3 and calculates the contribution from individual events to the predicted outcome. The model outcome can be easily explained with the clinical evidence identified by the model algorithm. Here are examples: Member A had 36 medical encounters in the past three years: multiple office visits, lab tests and medications. The model predicts member A has a high risk of CKD3 with the following well-contributed clinical events - multiple high ‘Creatinine in Serum or Plasma’ tests and multiple low kidneys functioning ‘Glomerular filtration rate’ tests. Among the abnormal lab tests, more recent results contributed more to the prediction. The model also indicates regular office visits, no abnormal findings of medical examinations, and taking proper medications decreased the CKD3 risk. Member B had 104 medical encounters in the past 3 years and was predicted to have a low risk of CKD3, because the model didn’t identify diagnoses, procedures, or medications related to kidney disease, and many lab test results, including ‘Glomerular filtration rate’ were within the normal range. The model accurately predicts members A and B and provides interpretable clinical evidence that is validated by clinicians. Without extra effort, the interpretation is generated directly from the model and presented together with the occurrence date. Our model uses the medical data in its most raw format without any further data aggregation, transformation, or mapping. This greatly simplifies the data preparation process, mitigates the chance for error and eliminates post-modeling work needed for traditional model explanation. To our knowledge, this is the first paper on an interpretable deep-learning model using a 3-level attention structure, sourcing both EMR and claim data, including all 4 types of medical data, on the entire Medicare population of a big insurance company, and more importantly, directly generating model interpretation to support user decision. In the future, we plan to enrich the model input by adding patients’ demographics and information from free-texted physician notes.Keywords: deep learning, interpretability, attention, big data, medical conditions
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