Search results for: spatial multi-criteria analysis model
37275 Modelling of Heating and Evaporation of Biodiesel Fuel Droplets
Authors: Mansour Al Qubeissi, Sergei S. Sazhin, Cyril Crua, Morgan R. Heikal
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This paper presents the application of the Discrete Component Model for heating and evaporation to multi-component biodiesel fuel droplets in direct injection internal combustion engines. This model takes into account the effects of temperature gradient, recirculation and species diffusion inside droplets. A distinctive feature of the model used in the analysis is that it is based on the analytical solutions to the temperature and species diffusion equations inside the droplets. Nineteen types of biodiesel fuels are considered. It is shown that a simplistic model, based on the approximation of biodiesel fuel by a single component or ignoring the diffusion of components of biodiesel fuel, leads to noticeable errors in predicted droplet evaporation time and time evolution of droplet surface temperature and radius.Keywords: heat/mass transfer, biodiesel, multi-component fuel, droplet
Procedia PDF Downloads 55937274 Design and Development of Chassis Made of Composite Material
Authors: P. Ravinder Reddy, Chaitanya Vishal Nalli, B. Tulja Lal, Anusha Kankanala
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The chassis frame of an automobile with different sections have been considered for different loads. The orthotropic materials are selected to get the stability by varying fiber angle, fiber thickness, laminates, fiber properties, matrix properties and elastic ratios. The geometric model of chassis frame is carried out with parametric modelling approach. The analysis of chassis frame is carried out with ANSYS FEA software. The static and dynamic analysis of chassis frame is carried out by varying geometric parameters, orthotropic properties, materials and various sections. The static and dynamic response is discussed in detail in different sections.Keywords: chassis frame, dynamic response, geometric model, orthotropic materials
Procedia PDF Downloads 32637273 Integrated Dynamic Analysis of Semi-Submersible Flap Type Concept
Authors: M. Rafiur Rahman, M. Mezbah Uddin, Mohammad Irfan Uddin, M. Moinul Islam
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With a rapid development of offshore renewable energy industry, the research activities in regards of harnessing power from offshore wind and wave energy are increasing day by day. Integration of wind turbines and wave energy converters into one combined semi-submersible platform might be a cost-economy and beneficial option. In this paper, the coupled integrated dynamic analysis in the time domain (TD) of a simplified semi-submersible flap type concept (SFC) is accomplished via state-of-the-art numerical code referred as Simo-Riflex-Aerodyn (SRA). This concept is a combined platform consisting of a semi-submersible floater supporting a 5 MW horizontal axis wind turbine (WT) and three elliptical shaped flap type wave energy converters (WECs) on three pontoons. The main focus is to validate the numerical model of SFC with experimental results and perform the frequency domain (FD) and TD response analysis. The numerical analysis is performed using potential flow theory for hydrodynamics and blade element momentum (BEM) theory for aerodynamics. A variety of environmental conditions encompassing the functional & survival conditions for short-term sea (1-hour simulation) are tested to evaluate the sustainability of the SFC. The numerical analysis is performed in full scale. Finally, the time domain analysis of heave, pitch & surge motions is performed numerically using SRA and compared with the experimental results. Due to the simplification of the model, there are some discrepancies which are discussed in brief.Keywords: coupled integrated dynamic analysis, SFC, time domain analysis, wave energy converters
Procedia PDF Downloads 21437272 Single-Molecule Analysis of Structure and Dynamics in Polymer Materials by Super-Resolution Technique
Authors: Hiroyuki Aoki
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The physical properties of polymer materials are dependent on the conformation and molecular motion of a polymer chain. Therefore, the structure and dynamic behavior of the single polymer chain have been the most important concerns in the field of polymer physics. However, it has been impossible to directly observe the conformation of the single polymer chain in a bulk medium. In the current work, the novel techniques to study the conformation and dynamics of a single polymer chain are proposed. Since a fluorescence method is extremely sensitive, the fluorescence microscopy enables the direct detection of a single molecule. However, the structure of the polymer chain as large as 100 nm cannot be resolved by conventional fluorescence methods because of the diffraction limit of light. In order to observe the single chains, we developed the labeling method of polymer materials with a photo-switchable dye and the super-resolution microscopy. The real-space conformational analysis of single polymer chains with the spatial resolution of 15-20 nm was achieved. The super-resolution microscopy enables us to obtain the three-dimensional coordinates; therefore, we succeeded the conformational analysis in three dimensions. The direct observation by the nanometric optical microscopy would reveal the detailed information on the molecular processes in the various polymer systems.Keywords: polymer materials, single molecule, super-resolution techniques, conformation
Procedia PDF Downloads 29737271 Urban Land Expansion Impact Assessment on Agriculture Land in Kabul City, Afghanistan
Authors: Ahmad Sharif Ahmadi, Yoshitaka Kajita
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Kabul city is experiencing urban land expansion in an unprecedented scale, especially since the last decade. With massive population expansion and fast economic development, urban land has increasingly expanded and encroached upon agriculture land during the urbanization history of the city. This paper evaluates the integrated urban land expansion impact on agriculture land in Kabul city since the formation of the basic structure of the city between 1962-1964. The paper studies the temporal and spatial characteristic of agriculture land and agriculture land loss in Kabul city using geographic information system (GIS) and remote sensing till 2008. Many temporal Landsat Thematic Mapper (TM) imageries were interpreted to detect the temporal and spatial characteristics of agriculture land loss. Different interval study periods, however, had vast difference in the agriculture land loss which is due to the urban land expansion trends in the city. the high number of Agriculture land adjacent to the city center and urban fringe have been converted into urban land during the study period in the city, as the agriculture land is highly correlated with the urban land.Keywords: agriculture land, agriculture land loss, Kabul city, urban land expansion, urbanization
Procedia PDF Downloads 40537270 The Comparison of Joint Simulation and Estimation Methods for the Geometallurgical Modeling
Authors: Farzaneh Khorram
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This paper endeavors to construct a block model to assess grinding energy consumption (CCE) and pinpoint blocks with the highest potential for energy usage during the grinding process within a specified region. Leveraging geostatistical techniques, particularly joint estimation, or simulation, based on geometallurgical data from various mineral processing stages, our objective is to forecast CCE across the study area. The dataset encompasses variables obtained from 2754 drill samples and a block model comprising 4680 blocks. The initial analysis encompassed exploratory data examination, variography, multivariate analysis, and the delineation of geological and structural units. Subsequent analysis involved the assessment of contacts between these units and the estimation of CCE via cokriging, considering its correlation with SPI. The selection of blocks exhibiting maximum CCE holds paramount importance for cost estimation, production planning, and risk mitigation. The study conducted exploratory data analysis on lithology, rock type, and failure variables, revealing seamless boundaries between geometallurgical units. Simulation methods, such as Plurigaussian and Turning band, demonstrated more realistic outcomes compared to cokriging, owing to the inherent characteristics of geometallurgical data and the limitations of kriging methods.Keywords: geometallurgy, multivariate analysis, plurigaussian, turning band method, cokriging
Procedia PDF Downloads 5437269 Role of Energy Storage in Renewable Electricity Systems in The Gird of Ethiopia
Authors: Dawit Abay Tesfamariam
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Ethiopia’s Climate- Resilient Green Economy (ECRGE) strategy focuses mainly on generating and proper utilization of renewable energy (RE). Nonetheless, the current electricity generation of the country is dominated by hydropower. The data collected in 2016 by Ethiopian Electric Power (EEP) indicates that the intermittent RE sources from solar and wind energy were only 8 %. On the other hand, the EEP electricity generation plan in 2030 indicates that 36.1 % of the energy generation share will be covered by solar and wind sources. Thus, a case study was initiated to model and compute the balance and consumption of electricity in three different scenarios: 2016, 2025, and 2030 using the EnergyPLAN Model (EPM). Initially, the model was validated using the 2016 annual power-generated data to conduct the EnergyPLAN (EP) analysis for two predictive scenarios. The EP simulation analysis using EPM for 2016 showed that there was no significant excess power generated. Thus, the EPM was applied to analyze the role of energy storage in RE in Ethiopian grid systems. The results of the EP simulation analysis showed there will be excess production of 402 /7963 MW average and maximum, respectively, in 2025. The excess power was in the three rainy months of the year (June, July, and August). The outcome of the model also showed that in the dry seasons of the year, there would be excess power production in the country. Consequently, based on the validated outcomes of EP indicates, there is a good reason to think about other alternatives for the utilization of excess energy and storage of RE. Thus, from the scenarios and model results obtained, it is realistic to infer that if the excess power is utilized with a storage system, it can stabilize the grid system and be exported to support the economy. Therefore, researchers must continue to upgrade the current and upcoming storage system to synchronize with potentials that can be generated from renewable energy.Keywords: renewable energy, power, storage, wind, energy plan
Procedia PDF Downloads 7237268 Procedure Model for Data-Driven Decision Support Regarding the Integration of Renewable Energies into Industrial Energy Management
Authors: M. Graus, K. Westhoff, X. Xu
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The climate change causes a change in all aspects of society. While the expansion of renewable energies proceeds, industry could not be convinced based on general studies about the potential of demand side management to reinforce smart grid considerations in their operational business. In this article, a procedure model for a case-specific data-driven decision support for industrial energy management based on a holistic data analytics approach is presented. The model is executed on the example of the strategic decision problem, to integrate the aspect of renewable energies into industrial energy management. This question is induced due to considerations of changing the electricity contract model from a standard rate to volatile energy prices corresponding to the energy spot market which is increasingly more affected by renewable energies. The procedure model corresponds to a data analytics process consisting on a data model, analysis, simulation and optimization step. This procedure will help to quantify the potentials of sustainable production concepts based on the data from a factory. The model is validated with data from a printer in analogy to a simple production machine. The overall goal is to establish smart grid principles for industry via the transformation from knowledge-driven to data-driven decisions within manufacturing companies.Keywords: data analytics, green production, industrial energy management, optimization, renewable energies, simulation
Procedia PDF Downloads 42937267 A Study on Inference from Distance Variables in Hedonic Regression
Authors: Yan Wang, Yasushi Asami, Yukio Sadahiro
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In urban area, several landmarks may affect housing price and rents, hedonic analysis should employ distance variables corresponding to each landmarks. Unfortunately, the effects of distances to landmarks on housing prices are generally not consistent with the true price. These distance variables may cause magnitude error in regression, pointing a problem of spatial multicollinearity. In this paper, we provided some approaches for getting the samples with less bias and method on locating the specific sampling area to avoid the multicollinerity problem in two specific landmarks case.Keywords: landmarks, hedonic regression, distance variables, collinearity, multicollinerity
Procedia PDF Downloads 44837266 CFD Simulation for Flow Behavior in Boiling Water Reactor Vessel and Upper Pool under Decommissioning Condition
Authors: Y. T. Ku, S. W. Chen, J. R. Wang, C. Shih, Y. F. Chang
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In order to respond the policy decision of non-nuclear homes, Tai Power Company (TPC) will provide the decommissioning project of Kuosheng Nuclear power plant (KSNPP) to meet the regulatory requirement in near future. In this study, the computational fluid dynamics (CFD) methodology has been employed to develop a flow prediction model for boiling water reactor (BWR) with upper pool under decommissioning stage. The model can be utilized to investigate the flow behavior as the vessel combined with upper pool and continuity cooling system. At normal operating condition, different parameters are obtained for the full fluid area, including velocity, mass flow, and mixing phenomenon in the reactor pressure vessel (RPV) and upper pool. Through the efforts of the study, an integrated simulation model will be developed for flow field analysis of decommissioning KSNPP under normal operating condition. It can be expected that a basis result for future analysis application of TPC can be provide from this study.Keywords: CFD, BWR, decommissioning, upper pool
Procedia PDF Downloads 25537265 Development of an Analytical Model for a Synchronous Permanent Magnet Generator
Authors: T. Sahbani, M. Bouteraa, R. Wamkeue
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Wind Turbine are considered to be one of the more efficient system of energy production nowadays, a reason that leads the main industrial companies in wind turbine construction and researchers in over the world to look for better performance and one of the ways for that is the use of the synchronous permanent magnet generator. In this context, this work is about developing an analytical model that could simulate different situation in which the synchronous generator may go through, and of course this model match perfectly with the numerical and experimental model.Keywords: MATLAB, synchronous permanent magnet generator, wind turbine, analytical model
Procedia PDF Downloads 54037264 Finite Element Analysis of Cold Formed Steel Screwed Connections
Authors: Jikhil Joseph, S. R. Satish Kumar
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Steel Structures are commonly used for rapid erections and multistory constructions due to its inherent advantages. However, the high accuracy required in detailing and heavier sections, make it difficult to erect in place and transport. Cold Formed steel which are specially made by reducing carbon and other alloys are used nowadays to make thin-walled structures. Various types of connections are being reported as well as practiced for the thin-walled members such as bolting, riveting, welding and other mechanical connections. Commonly self-drilling screw connections are used for cold-formed purlin sheeting connection. In this paper an attempt is made to develop a moment resting frame which can be rapidly and remotely constructed with thin walled sections and self-drilling screws. Semi-rigid Moment connections are developed with Rectangular thin-walled tubes and the screws. The Finite Element Analysis programme ABAQUS is used for modelling the screwed connections. The various modelling procedures for simulating the connection behavior such as tie-constraint model, oriented spring model and solid interaction modelling are compared and are critically reviewed. From the experimental validations the solid-interaction modelling identified to be the most accurate one and are used for predicting the connection behaviors. From the finite element analysis, hysteresis curves and the modes of failure were identified. Parametric studies were done on the connection model to optimize the connection configurations to get desired connection characteristics.Keywords: buckling, cold formed steel, finite element analysis, screwed connections
Procedia PDF Downloads 17937263 A Non-linear Damage Model For The Annulus Of the Intervertebral Disc Under Cyclic Loading, Including Recovery
Authors: Shruti Motiwale, Xianlin Zhou, Reuben H. Kraft
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Military and sports personnel are often required to wear heavy helmets for extended periods of time. This leads to excessive cyclic loads on the neck and an increased chance of injury. Computational models offer one approach to understand and predict the time progression of disc degeneration under severe cyclic loading. In this paper, we have applied an analytic non-linear damage evolution model to estimate damage evolution in an intervertebral disc due to cyclic loads over decade-long time periods. We have also proposed a novel strategy for inclusion of recovery in the damage model. Our results show that damage only grows 20% in the initial 75% of the life, growing exponentially in the remaining 25% life. The analysis also shows that it is crucial to include recovery in a damage model.Keywords: cervical spine, computational biomechanics, damage evolution, intervertebral disc, continuum damage mechanics
Procedia PDF Downloads 56437262 A Study on Human Musculoskeletal Model for Cycle Fitting: Comparison with EMG
Authors: Yoon- Ho Shin, Jin-Seung Choi, Dong-Won Kang, Jeong-Woo Seo, Joo-Hack Lee, Ju-Young Kim, Dae-Hyeok Kim, Seung-Tae Yang, Gye-Rae Tack
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It is difficult to study the effect of various variables on cycle fitting through actual experiment. To overcome such difficulty, the forward dynamics of a musculoskeletal model was applied to cycle fitting in this study. The measured EMG data were compared with the muscle activities of the musculoskeletal model through forward dynamics. EMG data were measured from five cyclists who do not have musculoskeletal diseases during three minutes pedaling with a constant load (150 W) and cadence (90 RPM). The muscles used for the analysis were the Vastus Lateralis (VL), Tibialis Anterior (TA), Bicep Femoris (BF), and Gastrocnemius Medial (GM). Person’s correlation coefficients of the muscle activity patterns, the peak timing of the maximum muscle activities, and the total muscle activities were calculated and compared. BIKE3D model of AnyBody (Anybodytech, Denmark) was used for the musculoskeletal model simulation. The comparisons of the actual experiments with the simulation results showed significant correlations in the muscle activity patterns (VL: 0.789, TA: 0.503, BF: 0.468, GM: 0.670). The peak timings of the maximum muscle activities were distributed at particular phases. The total muscle activities were compared with the normalized muscle activities, and the comparison showed about 10% difference in the VL (+10%), TA (+9.7%), and BF (+10%), excluding the GM (+29.4%). Thus, it can be concluded that muscle activities of model & experiment showed similar results. The results of this study indicated that it was possible to apply the simulation of further improved musculoskeletal model to cycle fitting.Keywords: musculoskeletal modeling, EMG, cycle fitting, simulation
Procedia PDF Downloads 56037261 Forecasting Materials Demand from Multi-Source Ordering
Authors: Hui Hsin Huang
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The downstream manufactures will order their materials from different upstream suppliers to maintain a certain level of the demand. This paper proposes a bivariate model to portray this phenomenon of material demand. We use empirical data to estimate the parameters of model and evaluate the RMSD of model calibration. The results show that the model has better fitness.Keywords: recency, ordering time, materials demand quantity, multi-source ordering
Procedia PDF Downloads 52937260 Comparative Study of Titanium and Polyetheretherketone Cranial Implant Using Finite Element Model
Authors: Khaja Moiduddin, Sherif Mohammed Elseufy, Hisham Alkhalefah
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Recent advances in three-dimensional (3D) printing, medical imaging, and implant design may alter how craniomaxillofacial surgeons construct individualized treatments using patient data. By utilizing medical image data, medical professionals can obtain detailed information about a patient's injuries, enabling them to conduct a thorough preoperative assessment while ensuring the implant's accuracy. However, selecting the right implant material requires careful consideration of various mechanical properties. This study aims to compare the two commonly used implant material for cranial reconstruction which includes titanium (Ti6Al4V) and Polyetheretherketone (PEEK). Biomechanical analysis was performed to study the implant behavior, by keeping the implant design and fixation constant in both cases. A finite element model was created and analyzed under loading conditions. The finite element analysis proves that although Ti6Al4V is stronger than PEEK but, its mechanical strength is adequate to bear the loads of the adjacent bone tissue.Keywords: cranial reconstruction, titanium implants, PEEK, finite element model
Procedia PDF Downloads 6337259 Correlation Analysis of Energy Use, Architectural Design and Residential Lifestyle in Japan Smart Community
Authors: Tran Le Na, Didit Novianto, Yoshiaki Ushifusa, Weijun Gao
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This paper introduces the characteristics of Japanese residential lifestyle and Japanese Architectural housing design, meanwhile, summarizes the results from an analysis of energy use of 12 households in electric-only multi dwellings in Higashida Smart Community, Kitakyushu, Japan. Using hourly load and daily load data collected from smart meter, we explore correlations of energy use in households according to the incentive of different levels of architectural characteristics and lifestyle, following three factors: Space (Living room, Kitchen, Bedroom, Bathroom), Time (daytime and night time, weekdays and weekend) and User (Elderly, Parents, Kids). The energy consumption reports demonstrated that the essential demand of household’s response to variable factors. From that exploratory analysis, we can define the role of housing equipment layout and spatial layout in residential housing design. Likewise, determining preferred spaces and time use can help to optimize energy consumption in households. This paper contributes to the application of Smart Home Energy Management System in Smart Community in Japan and provides a good experience to other countries.Keywords: smart community, energy efficiency, architectural housing design, residential lifestyle
Procedia PDF Downloads 20037258 Nonlinear Model Predictive Control of Water Quality in Drinking Water Distribution Systems with DBPs Objetives
Authors: Mingyu Xie, Mietek Brdys
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The paper develops a non-linear model predictive control (NMPC) of water quality in drinking water distribution systems (DWDS) based on the advanced non-linear quality dynamics model including disinfections by-products (DBPs). A special attention is paid to the analysis of an impact of the flow trajectories prescribed by an upper control level of the recently developed two-time scale architecture of an integrated quality and quantity control in DWDS. The new quality controller is to operate within this architecture in the fast time scale as the lower level quality controller. The controller performance is validated by a comprehensive simulation study based on an example case study DWDS.Keywords: model predictive control, hierarchical control structure, genetic algorithm, water quality with DBPs objectives
Procedia PDF Downloads 31137257 Performance Evaluation of Various Segmentation Techniques on MRI of Brain Tissue
Authors: U.V. Suryawanshi, S.S. Chowhan, U.V Kulkarni
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Accuracy of segmentation methods is of great importance in brain image analysis. Tissue classification in Magnetic Resonance brain images (MRI) is an important issue in the analysis of several brain dementias. This paper portraits performance of segmentation techniques that are used on Brain MRI. A large variety of algorithms for segmentation of Brain MRI has been developed. The objective of this paper is to perform a segmentation process on MR images of the human brain, using Fuzzy c-means (FCM), Kernel based Fuzzy c-means clustering (KFCM), Spatial Fuzzy c-means (SFCM) and Improved Fuzzy c-means (IFCM). The review covers imaging modalities, MRI and methods for noise reduction and segmentation approaches. All methods are applied on MRI brain images which are degraded by salt-pepper noise demonstrate that the IFCM algorithm performs more robust to noise than the standard FCM algorithm. We conclude with a discussion on the trend of future research in brain segmentation and changing norms in IFCM for better results.Keywords: image segmentation, preprocessing, MRI, FCM, KFCM, SFCM, IFCM
Procedia PDF Downloads 32337256 Modal Analysis of Power System with a Microgrid
Authors: Burak Yildirim, Muhsin Tunay Gençoğlu
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A microgrid (MG) is a small power grid composed of localized medium or low level power generation, storage systems, and loads. In this paper, the effects of a MG on power systems voltage stability are shown. The MG model, designed to demonstrate the effects of the MG, was applied to the IEEE 14 bus power system which is widely used in power system stability studies. Eigenvalue and modal analysis methods were used in simulation studies. In the study results, it is seen that MGs affect system voltage stability positively by increasing system voltage instability limit value for buses of a power system in which MG are placed.Keywords: eigenvalue analysis, microgrid, modal analysis, voltage stability
Procedia PDF Downloads 36537255 A Controlled Mathematical Model for Population Dynamics in an Infested Honeybees Colonies
Authors: Chakib Jerry, Mounir Jerry
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In this paper, a mathematical model of infested honey bees colonies is formulated in order to investigate Colony Collapse Disorder in a honeybee colony. CCD, as it is known, is a major problem on honeybee farms because of the massive decline in colony numbers. We introduce to the model a control variable which represents forager protection. We study the controlled model to derive conditions under which the bee colony can fight off epidemic. Secondly we study the problem of minimizing prevention cost under model’s dynamics constraints.Keywords: honey bee, disease transmission model, disease control honeybees, optimal control
Procedia PDF Downloads 41637254 Estimation of Soil Erosion Potential in Herat Province, Afghanistan
Authors: M. E. Razipoor, T. Masunaga, K. Sato, M. S. Saboory
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Estimation of soil erosion is economically and environmentally important in Herat, Afghanistan. Degradation of soil has negative impact (decreased soil fertility, destroyed soil structure, and consequently soil sealing and crusting) on life of Herat residents. Water and wind are the main erosive factors causing soil erosion in Herat. Furthermore, scarce vegetation cover, exacerbated by socioeconomic constraint, and steep slopes accelerate soil erosion. To sustain soil productivity and reduce soil erosion impact on human life, due to sustaining agricultural production and auditing the environment, it is needed to quantify the magnitude and extent of soil erosion in a spatial domain. Thus, this study aims to estimate soil loss potential and its spatial distribution in Herat, Afghanistan by applying RUSLE in GIS environment. The rainfall erosivity factor ranged between values of 125 and 612 (MJ mm ha-1 h-1 year-1). Soil erodibility factor varied from 0.036 to 0.073 (Mg h MJ-1 mm-1). Slope length and steepness factor (LS) values were between 0.03 and 31.4. The vegetation cover factor (C), derived from NDVI analysis of Landsat-8 OLI scenes, resulting in range of 0.03 to 1. Support practice factor (P) were assigned to a value of 1, since there is not significant mitigation practices in the study area. Soil erosion potential map was the product of these factors. Mean soil erosion rate of Herat Province was 29 Mg ha-1 year-1 that ranged from 0.024 Mg ha-1 year-1 in flat areas with dense vegetation cover to 778 Mg ha-1 year-1 in sharp slopes with high rainfall but least vegetation cover. Based on land cover map of Afghanistan, areas with soil loss rate higher than soil loss tolerance (8 Mg ha-1 year-1) occupies 98% of Forests, 81% rangelands, 64% barren lands, 60% rainfed lands, 28% urban area and 18% irrigated Lands.Keywords: Afghanistan, erosion, GIS, Herat, RUSLE
Procedia PDF Downloads 42537253 Analysis of the Unreliable M/G/1 Retrial Queue with Impatient Customers and Server Vacation
Authors: Fazia Rahmoune, Sofiane Ziani
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Retrial queueing systems have been extensively used to stochastically model many problems arising in computer networks, telecommunication, telephone systems, among others. In this work, we consider a $M/G/1$ retrial queue with an unreliable server with random vacations and two types of primary customers, persistent and impatient. This model involves the unreliability of the server, which can be subject to physical breakdowns and takes into account the correctives maintenances for restoring the service when a failure occurs. On the other hand, we consider random vacations, which can model the preventives maintenances for improving system performances and preventing breakdowns. We give the necessary and sufficient stability condition of the system. Then, we obtain the joint probability distribution of the server state and the number of customers in orbit and derive the more useful performance measures analytically. Moreover, we also analyze the busy period of the system. Finally, we derive the stability condition and the generating function of the stationary distribution of the number of customers in the system when there is no vacations and impatient customers, and when there is no vacations, server failures and impatient customers.Keywords: modeling, retrial queue, unreliable server, vacation, stochastic analysis
Procedia PDF Downloads 17737252 Factors Influencing the Choice of Multi-Month Drug Dispensing Model Amongst Children and Adolescents Living with HIV (C/ALHIV) in Eswatini
Authors: Mbuso Siwela
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Background: The Sub-Saharan Africa region has the greatest number of people eligible to receive antiretroviral treatment (ART). Multi-month Drug dispensing (MMD) of antiretroviral treatment (ART) aims to reduce patient-related barriers to access long-term treatment and improve health system efficiency. In Eswatini, however, few children and adolescents are on MMD. Young Heroes is implementing an HIV program that aims to avert new HIV infections in children and youth and improve treatment outcomes for children and adolescents living with HIV (C/ALHIV: 0-19 Years) and OVC caregivers with HIV prevention and impact mitigation interventions that prevent new HIV infections and reduce vulnerability. Aim of the study: The study aimed to ascertain factors that are associated with the assignment of the MMD model on C/ALHIVs. Methodology: The project provides treatment adherence support through well-trained community cadres (Home Visitors - HVs) at both community and health facility levels. During door-to-door visits, HVs track all C/ALHIV enrolled in the project monthly and refer any who might have stopped or interrupted treatment. C/ALHIV with unsuppressed viral load is supported through case conferencing and teen clubs. A quantitative cross-sectional analysis was conducted using STATA for children and adolescents living with HIV enrolled in the project. Bivariate analysis was conducted, and the Logistic Regression model was used to ascertain the effects of duration on ART on the choice of MMD model. Results: Data for 544 C/ALHIV (0-19 Years) was analyzed in STATA. Results show a strong association between (duration on ART, Age, being in teen club) and enrolment in an MMD model. Duration on ART is a major predictor for the choice of MMD model at (95% CI: 0.0012905 – 0.0039812; P = <0.0001). C/ALHIV who have been on ART for less than a year are less likely to be on MMD. C/ALHIVs who are 1 or more years on ART are more likely to be in 3 months dispensing, while those who are 5 years or more are most likely to be in 6 months model.Keywords: C/ALHIV, OVC, HIV, treatment
Procedia PDF Downloads 1537251 Popularization of Persian Scientific Articles in the Public Media: An Analysis Based on Experimental Meta-function View Point
Authors: Behnaz Zolfaghari
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In civilized societies, linguists seek to find suitable equivalents for scientific terms in the common language of their society. Many researches have conducted surveys about language of science on one hand and media discourse on the other, but the goal of this research is the comparative analysis of science discourse in Persian academic media and public discourse in the general Persian media by applying experimental meta-function as one of the four theoretical tools introduced by Holiday’s Systemic Functional Grammar .The said analysis aims to explore the processes that can convert the language in which scientific facts are published to a language well suited to the interested layman. The results of comparison show that these two discourses use differently six processes of experimental meta-function. Comparing the redundancy of different processes, the researcher tried to re-identify these differences in these two discourses and present a model for the procedures of converting science discourse to popularized discourse. This model can be useful for those journalists and textbook authors who want to restate scientific technical texts in a simple style for inexpert addresser including general people and students.Keywords: systemic functional grammar, discourse analysis, science language, popularization, media discourse
Procedia PDF Downloads 18837250 Material Parameter Identification of Modified AbdelKarim-Ohno Model
Authors: Martin Cermak, Tomas Karasek, Jaroslav Rojicek
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The key role in phenomenological modelling of cyclic plasticity is good understanding of stress-strain behaviour of given material. There are many models describing behaviour of materials using numerous parameters and constants. Combination of individual parameters in those material models significantly determines whether observed and predicted results are in compliance. Parameter identification techniques such as random gradient, genetic algorithm, and sensitivity analysis are used for identification of parameters using numerical modelling and simulation. In this paper genetic algorithm and sensitivity analysis are used to study effect of 4 parameters of modified AbdelKarim-Ohno cyclic plasticity model. Results predicted by Finite Element (FE) simulation are compared with experimental data from biaxial ratcheting test with semi-elliptical loading path.Keywords: genetic algorithm, sensitivity analysis, inverse approach, finite element method, cyclic plasticity, ratcheting
Procedia PDF Downloads 44437249 Neutral Heavy Scalar Searches via Standard Model Gauge Boson Decays at the Large Hadron Electron Collider with Multivariate Techniques
Authors: Luigi Delle Rose, Oliver Fischer, Ahmed Hammad
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In this article, we study the prospects of the proposed Large Hadron electron Collider (LHeC) in the search for heavy neutral scalar particles. We consider a minimal model with one additional complex scalar singlet that interacts with the Standard Model (SM) via mixing with the Higgs doublet, giving rise to an SM-like Higgs boson and a heavy scalar particle. Both scalar particles are produced via vector boson fusion and can be tested via their decays into pairs of SM particles, analogously to the SM Higgs boson. Using multivariate techniques, we show that the LHeC is sensitive to heavy scalars with masses between 200 and 800 GeV down to scalar mixing of order 0.01.Keywords: beyond the standard model, large hadron electron collider, multivariate analysis, scalar singlet
Procedia PDF Downloads 13237248 Development of Requirements Analysis Tool for Medical Autonomy in Long-Duration Space Exploration Missions
Authors: Lara Dutil-Fafard, Caroline Rhéaume, Patrick Archambault, Daniel Lafond, Neal W. Pollock
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Improving resources for medical autonomy of astronauts in prolonged space missions, such as a Mars mission, requires not only technology development, but also decision-making support systems. The Advanced Crew Medical System - Medical Condition Requirements study, funded by the Canadian Space Agency, aimed to create knowledge content and a scenario-based query capability to support medical autonomy of astronauts. The key objective of this study was to create a prototype tool for identifying medical infrastructure requirements in terms of medical knowledge, skills and materials. A multicriteria decision-making method was used to prioritize the highest risk medical events anticipated in a long-term space mission. Starting with those medical conditions, event sequence diagrams (ESDs) were created in the form of decision trees where the entry point is the diagnosis and the end points are the predicted outcomes (full recovery, partial recovery, or death/severe incapacitation). The ESD formalism was adapted to characterize and compare possible outcomes of medical conditions as a function of available medical knowledge, skills, and supplies in a given mission scenario. An extensive literature review was performed and summarized in a medical condition database. A PostgreSQL relational database was created to allow query-based evaluation of health outcome metrics with different medical infrastructure scenarios. Critical decision points, skill and medical supply requirements, and probable health outcomes were compared across chosen scenarios. The three medical conditions with the highest risk rank were acute coronary syndrome, sepsis, and stroke. Our efforts demonstrate the utility of this approach and provide insight into the effort required to develop appropriate content for the range of medical conditions that may arise.Keywords: decision support system, event-sequence diagram, exploration mission, medical autonomy, scenario-based queries, space medicine
Procedia PDF Downloads 12237247 Advancing Spatial Mapping and Monitoring of Illegal Landfills for Deprived Urban Areas in Romania
Authors: ȘercăIanu Mihai, Aldea Mihaela, Iacoboaea Cristina, Luca Oana, Nenciu Ioana
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The emergence and neutralization of illegal waste dumps represent a global concern for waste management ecosystems with a particularly pronounced impact on disadvantaged communities. All over the world, and in this particular case in Romania, a relevant number of people resided in houses lacking any legal forms such as land ownership documents or building permits. These areas are referred to as “informal settlements”. An increasing number of regions and cities in Romania are struggling to manage their waste dumps, especially in the context of increasing poverty and lack of regulation related to informal settlements. An example of such informal settlement can be found at the terminus of Bistra Street in Câlnic, which falls under the jurisdiction of the Municipality of Reșița in Caras Severin County. The article presents a case study that focuses on employing remote sensing techniques and spatial data to monitor and map illegal waste practices, with subsequent integration into a geographic information system tailored for the Reșița community. In addition, the paper outlines the steps involved in devising strategies aimed at enhancing waste management practices in disadvantaged areas, aligning with the shift toward a circular economy. Results presented in the paper contain a spatial mapping and visualization methodology calibrated with in situ data collection applicable for identifying illegal landfills. The emergence and neutralization of illegal dumps pose a challenge in the field of waste management. These approaches, which prove effective where conventional solutions have failed, need to be replicated and adopted more wisely.Keywords: waste dumps, waste management, monitoring, GIS, informal settlements
Procedia PDF Downloads 7237246 The Practise of Hand Drawing as a Premier Form of Representation in Architectural Design Teaching: The Case of FAUP
Authors: Rafael Santos, Clara Pimenta Do Vale, Barbara Bogoni, Poul Henning Kirkegaard
Abstract:
In the last decades, the relevance of hand drawing has decreased in the scope of architectural education. However, some schools continue to recognize its decisive role, not only in the architectural design teaching, but in the whole of architectural training. With this paper it is intended to present the results of a research developed on the following problem: the practise of hand drawing as a premier form of representation in architectural design teaching. The research had as its object the educational model of the Faculty of Architecture of the University of Porto (FAUP) and was led by three main objectives: to identify the circumstance that promoted hand drawing as a form of representation in FAUP's model; to characterize the types of hand drawing and their role in that model; to determine the particularities of hand drawing as a premier form of representation in architectural design teaching. Methodologically, the research was conducted according to a qualitative embedded single-case study design. The object – i.e., the educational model – was approached in FAUP case considering its Context and three embedded unities of analysis: the educational Purposes, Principles and Practices. In order to guide the procedures of data collection and analysis, a Matrix for the Characterization (MCC) was developed. As a methodological tool, the MCC allowed to relate the three embedded unities of analysis with the three main sources of evidence where the object manifests itself: the professors, expressing how the model is Assumed; the architectural design classes, expressing how the model is Achieved; and the students, expressing how the model is Acquired. The main research methods used were the naturalistic and participatory observation, in-person-interview and documentary and bibliographic review. The results reveal that the educational model of FAUP – following the model of the former Porto School – was largely due to the methodological foundations created with the hand drawing teaching-learning processes. In the absence of a culture of explicit theoretical elaboration or systematic research, hand drawing was the support for the continuity of the school, an expression of a unified thought about what should be the reflection and practice of architecture. As a form of representation, hand drawing plays a transversal role in the entire educational model, since its purposes are not limited to the conception of architectural design – it is also a means for perception, analysis and synthesis. Regarding the architectural design teaching, there seems to be an understanding of three complementary dimensions of didactics: the instrumental, methodological and propositional dimension. At FAUP, hand drawing is recognized as the common denominator among these dimensions, according to the idea of "globality of drawing". It is expected that the knowledge base developed in this research may have three main contributions: to contribute to the maintenance and valorisation of FAUP’s model; through the precise description of the methodological procedures, to contribute by transferability to similar studies; through the critical and objective framework of the problem underlying the hand drawing in architectural design teaching, to contribute to the broader discussion concerning the contemporary challenges on architectural education.Keywords: architectural design teaching, architectural education, forms of representation, hand drawing
Procedia PDF Downloads 125