Search results for: sharp single index model
23211 A Sharp Interface Model for Simulating Seawater Intrusion in the Coastal Aquifer of Wadi Nador (Algeria)
Authors: Abdelkader Hachemi, Boualem Remini
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Seawater intrusion is a significant challenge faced by coastal aquifers in the Mediterranean basin. This study aims to determine the position of the sharp interface between seawater and freshwater in the aquifer of Wadi Nador, located in the Wilaya of Tipaza, Algeria. A numerical areal sharp interface model using the finite element method is developed to investigate the spatial and temporal behavior of seawater intrusion. The aquifer is assumed to be homogeneous and isotropic. The simulation results are compared with geophysical prospection data obtained through electrical methods in 2011 to validate the model. The simulation results demonstrate a good agreement with the geophysical prospection data, confirming the accuracy of the sharp interface model. The position of the sharp interface in the aquifer is found to be approximately 1617 meters from the sea. Two scenarios are proposed to predict the interface position for the year 2024: one without pumping and the other with pumping. The results indicate a noticeable retreat of the sharp interface position in the first scenario, while a slight decline is observed in the second scenario. The findings of this study provide valuable insights into the dynamics of seawater intrusion in the Wadi Nador aquifer. The predicted changes in the sharp interface position highlight the potential impact of pumping activities on the aquifer's vulnerability to seawater intrusion. This study emphasizes the importance of implementing measures to manage and mitigate seawater intrusion in coastal aquifers. The sharp interface model developed in this research can serve as a valuable tool for assessing and monitoring the vulnerability of aquifers to seawater intrusion.Keywords: seawater intrusion, sharp interface, coastal aquifer, algeria
Procedia PDF Downloads 11923210 Seawater Intrusion in the Coastal Aquifer of Wadi Nador (Algeria)
Authors: Abdelkader Hachemi & Boualem Remini
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Seawater intrusion is a significant challenge faced by coastal aquifers in the Mediterranean basin. This study aims to determine the position of the sharp interface between seawater and freshwater in the aquifer of Wadi Nador, located in the Wilaya of Tipaza, Algeria. A numerical areal sharp interface model using the finite element method is developed to investigate the spatial and temporal behavior of seawater intrusion. The aquifer is assumed to be homogeneous and isotropic. The simulation results are compared with geophysical prospection data obtained through electrical methods in 2011 to validate the model. The simulation results demonstrate a good agreement with the geophysical prospection data, confirming the accuracy of the sharp interface model. The position of the sharp interface in the aquifer is found to be approximately 1617 meters from the sea. Two scenarios are proposed to predict the interface position for the year 2024: one without pumping and the other with pumping. The results indicate a noticeable retreat of the sharp interface position in the first scenario, while a slight decline is observed in the second scenario. The findings of this study provide valuable insights into the dynamics of seawater intrusion in the Wadi Nador aquifer. The predicted changes in the sharp interface position highlight the potential impact of pumping activities on the aquifer's vulnerability to seawater intrusion. This study emphasizes the importance of implementing measures to manage and mitigate seawater intrusion in coastal aquifers. The sharp interface model developed in this research can serve as a valuable tool for assessing and monitoring the vulnerability of aquifers to seawater intrusion.Keywords: seawater, intrusion, sharp interface, Algeria
Procedia PDF Downloads 7423209 Brainwave Classification for Brain Balancing Index (BBI) via 3D EEG Model Using k-NN Technique
Authors: N. Fuad, M. N. Taib, R. Jailani, M. E. Marwan
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In this paper, the comparison between k-Nearest Neighbor (kNN) algorithms for classifying the 3D EEG model in brain balancing is presented. The EEG signal recording was conducted on 51 healthy subjects. Development of 3D EEG models involves pre-processing of raw EEG signals and construction of spectrogram images. Then, maximum PSD values were extracted as features from the model. There are three indexes for the balanced brain; index 3, index 4 and index 5. There are significant different of the EEG signals due to the brain balancing index (BBI). Alpha-α (8–13 Hz) and beta-β (13–30 Hz) were used as input signals for the classification model. The k-NN classification result is 88.46% accuracy. These results proved that k-NN can be used in order to predict the brain balancing application.Keywords: power spectral density, 3D EEG model, brain balancing, kNN
Procedia PDF Downloads 48623208 Computing Some Topological Descriptors of Single-Walled Carbon Nanotubes
Authors: Amir Bahrami
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In the fields of chemical graph theory, molecular topology, and mathematical chemistry, a topological index or a descriptor index also known as a connectivity index is a type of a molecular descriptor that is calculated based on the molecular graph of a chemical compound. Topological indices are numerical parameters of a graph which characterize its topology and are usually graph invariant. Topological indices are used for example in the development of quantitative structure-activity relationships (QSARs) in which the biological activity or other properties of molecules are correlated with their chemical structure. In this paper some descriptor index (descriptor index) of single-walled carbon nanotubes, is determined.Keywords: chemical graph theory, molecular topology, molecular descriptor, single-walled carbon nanotubes
Procedia PDF Downloads 33823207 The Research of Weights Identify of Harbin Ecological Security Evaluation Index Based on AHP
Authors: Rong Guo, Mengshi Huang, Yujing Bai
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With the rapid development of urbanization, the urban population increases and urban sprawl appeared. And these issues led to a sharp deterioration of the ecological environment. So, the urban ecological security evaluation was imminent. The weights identify of index was a key step of the research of ecological security evaluation. The AHP was widely used in the extensive research of weights identify of ecological security index. The characteristics of authority and quantitative can fully reflect the views of relevant experts. On the basis of building the ecological security evaluation index of Harbin, the paper combed and used the basic principle of the AHP, and calculated the weights of Harbin ecological security evaluation index through the process of the expert opinions “summary-feedback-summary”. And lay a foundation of future study of Harbin ecological security index, and guide the quantitative evaluation of Harbin ecological security.Keywords: AHP, ecological security, evaluation Index, weights identify, harbin
Procedia PDF Downloads 49623206 A New Prediction Model for Soil Compression Index
Authors: D. Mohammadzadeh S., J. Bolouri Bazaz
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This paper presents a new prediction model for compression index of fine-grained soils using multi-gene genetic programming (MGGP) technique. The proposed model relates the soil compression index to its liquid limit, plastic limit and void ratio. Several laboratory test results for fine-grained were used to develop the models. Various criteria were considered to check the validity of the model. The parametric and sensitivity analyses were performed and discussed. The MGGP method was found to be very effective for predicting the soil compression index. A comparative study was further performed to prove the superiority of the MGGP model to the existing soft computing and traditional empirical equations.Keywords: new prediction model, compression index soil, multi-gene genetic programming, MGGP
Procedia PDF Downloads 37423205 Experimental Study of Discharge with Sharp-Crested Weirs
Authors: E. Keramaris, V. Kanakoudis
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In this study the water flow in an open channel over a sharp-crested weir is investigated experimentally. For this reason a series of laboratory experiments were performed in an open channel with a sharp-crested weir. The maximum head expected over the weir, the total upstream water height and the downstream water height of the impact in the constant bed of the open channel were measured. The discharge was measured using a tank put right after the open channel. In addition, the discharge and the upstream velocity were also calculated using already known equations. The main finding is that the relative error percentage for the majority of the experimental measurements is ± 4%, meaning that the calculation of the discharge with a sharp-crested weir gives very good results compared to the numerical results from known equations.Keywords: sharp-crested weir, weir height, flow measurement, open channel flow
Procedia PDF Downloads 13923204 Stackelberg Security Game for Optimizing Security of Federated Internet of Things Platform Instances
Authors: Violeta Damjanovic-Behrendt
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This paper presents an approach for optimal cyber security decisions to protect instances of a federated Internet of Things (IoT) platform in the cloud. The presented solution implements the repeated Stackelberg Security Game (SSG) and a model called Stochastic Human behaviour model with AttRactiveness and Probability weighting (SHARP). SHARP employs the Subjective Utility Quantal Response (SUQR) for formulating a subjective utility function, which is based on the evaluations of alternative solutions during decision-making. We augment the repeated SSG (including SHARP and SUQR) with a reinforced learning algorithm called Naïve Q-Learning. Naïve Q-Learning belongs to the category of active and model-free Machine Learning (ML) techniques in which the agent (either the defender or the attacker) attempts to find an optimal security solution. In this way, we combine GT and ML algorithms for discovering optimal cyber security policies. The proposed security optimization components will be validated in a collaborative cloud platform that is based on the Industrial Internet Reference Architecture (IIRA) and its recently published security model.Keywords: security, internet of things, cloud computing, stackelberg game, machine learning, naive q-learning
Procedia PDF Downloads 35423203 Investments in Petroleum Industry Abnormally Normal: A Case Study Based on Petroleum and Natural Gas Companies in India
Authors: Radhika Ramanchi
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The oil market during 2014-2015 in India with large price fluctuations is very confusing to individual investor. The drop in oil prices supported stocks of some oil marketing companies (OMCs) like Bharat Petroleum Corporation, Hindustan Petroleum Corporation (HPCL) and Indian Oil Corporation etc their shares rose 84.74%, 128.63% and 59.16%, respectively. Lower oil prices, and lower current account, a smaller subsidy burden are the reasons for outperformance. On the other hand, lower crude prices giving downward pressure on upstream companies like Oil and Natural Gas Corp. Ltd (ONGC) and Reliance Petroleum (RIL) Oil India Ltd (OIL). Not having clarity on a subsidy sharing mechanism is the reason for downward trend on these stocks. Shares of ONGC and RIL have underperformed so far in 2015. When the oil price fall profits of the companies will effect, generate less money and may cut their dividends in Long run. In this situation this paper objective is to study investment strategies in oil marketing companies, by applying CAPM and Security Market Line.Keywords: petrol industry, price fluctuations, sharp single index model, SML, Markowitz model
Procedia PDF Downloads 22323202 Injection Practices among Private Medical Practitioners of Karachi Pakistan
Authors: Mohammad Tahir Yousafzai, Nighat Nisar, Rehana Khalil
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The aim of this study is to assess the practices of sharp injuries and factors leading to it among medical practitioners in slum areas of Karachi, Pakistan. A cross sectional study was conducted in slum areas of Landhi Town Karachi. All medical practitioners (317) running the private clinics in the areas were asked to participate in the study. Data was collected on self administered pre-tested structured questionnaires. The frequency with percentage and 95% confidence interval was calculated for at least one sharp injury (SI) in the last one year. The factors leading to sharp injuries were assessed using multiple logistic regressions. About 80% of private medical practitioners consented to participate. Among these 87% were males and 13% were female. The mean age was 38±11 years and mean work experience was 12±9 years. The frequency of at least one sharp injury in the last one year was 27%(95% CI: 22.2-32). Almost 47% of Sharp Injuries were caused by needle recapping, less work experience, less than 14 years of schooling, more than 20 patients per day, administering more than 30 injections per day, reuse of syringes and needle recapping after use were significantly associated with sharp injuries. Injection practices were found inadequate among private medical practitioners in slum areas of Karachi, and the frequency of Sharp Injuries was found high in these areas. There is a risk of occupational transmission of blood borne infections among medical practitioners warranting an urgent need for launching awareness and training on standard precautions for private medical practitioners in the slum areas of Karachi.Keywords: injection practices, private practitioners, sharp injuries, blood borne infections
Procedia PDF Downloads 42023201 The Log S-fbm Nested Factor Model
Authors: Othmane Zarhali, Cécilia Aubrun, Emmanuel Bacry, Jean-Philippe Bouchaud, Jean-François Muzy
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The Nested factor model was introduced by Bouchaud and al., where the asset return fluctuations are explained by common factors representing the market economic sectors and residuals (noises) sharing with the factors a common dominant volatility mode in addition to the idiosyncratic mode proper to each residual. This construction infers that the factors-residuals log volatilities are correlated. Here, we consider the case of a single factor where the only dominant common mode is a S-fbm process (introduced by Peng, Bacry and Muzy) with Hurst exponent H around 0.11 and the residuals having in addition to the previous common mode idiosyncratic components with Hurst exponents H around 0. The reason for considering this configuration is twofold: preserve the Nested factor model’s characteristics introduced by Bouchaud and al. and propose a framework through which the stylized fact reported by Peng and al. is reproduced, where it has been observed that the Hurst exponents of stock indices are large as compared to those of individual stocks. In this work, we show that the Log S-fbm Nested factor model’s construction leads to a Hurst exponent of single stocks being the ones of the idiosyncratic volatility modes and the Hurst exponent of the index being the one of the common volatility modes. Furthermore, we propose a statistical procedure to estimate the Hurst factor exponent from the stock returns dynamics together with theoretical guarantees, with good results in the limit where the number of stocks N goes to infinity. Last but not least, we show that the factor can be seen as an index constructed from the single stocks weighted by specific coefficients.Keywords: hurst exponent, log S-fbm model, nested factor model, small intermittency approximation
Procedia PDF Downloads 4823200 Core Stability Index for Healthy Young Sri Lankan Population
Authors: V. M. B. K. T. Malwanage, S. Samita
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Core stability is one of the major determinants that contribute to preventing injuries, enhance performance, and improve quality of life of the human. Endurance of the four major muscle groups of the central ‘core’ of the human body is identified as the most reliable determinant of core stability amongst the other numerous causes which contribute to readily make one’s core stability. This study aimed to develop a ‘Core Stability Index’ to confer a single value for an individual’s core stability based on the four endurance test scores. Since it is possible that at least some of the test scores are not independent, possibility of constructing a single index using the multivariate method exploratory factor analysis was investigated in the study. The study sample was consisted of 400 healthy young individuals with the mean age of 23.74 ± 1.51 years and mean BMI (Body Mass Index) of 21.1 ± 4.18. The correlation analysis revealed highly significant (P < 0.0001) correlations between test scores and thus construction an index using these highly inter related test scores using the technique factor analysis was justified. The mean values of all test scores were significantly different between males and females (P < 0.0001), and therefore two separate core stability indices were constructed for the two gender groups. Moreover, having eigen values 3.103 and 2.305 for males and females respectively, indicated one factor exists for all four test scores and thus a single factor based index was constructed. The 95% reference intervals constructed using the index scores were -1.64 to 2.00 and -1.56 to 2.29 for males and females respectively. These intervals can effectively be used to diagnose those who need improvement in core stability. The practitioners should find that with a single value measure, they could be more consistent among themselves.Keywords: construction of indices, endurance test scores, muscle endurance, quality of life
Procedia PDF Downloads 16223199 Sensitive Analysis of the ZF Model for ABC Multi Criteria Inventory Classification
Authors: Makram Ben Jeddou
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The ABC classification is widely used by managers for inventory control. The classical ABC classification is based on the Pareto principle and according to the criterion of the annual use value only. Single criterion classification is often insufficient for a closely inventory control. Multi-criteria inventory classification models have been proposed by researchers in order to take into account other important criteria. From these models, we will consider the ZF model in order to make a sensitive analysis on the composite score calculated for each item. In fact, this score based on a normalized average between a good and a bad optimized index can affect the ABC items classification. We will then focus on the weights assigned to each index and propose a classification compromise.Keywords: ABC classification, multi criteria inventory classification models, ZF-model
Procedia PDF Downloads 50823198 The Threshold Values of Soil Water Index for Landslides on Country Road No.89
Authors: Ji-Yuan Lin, Yu-Ming Liou, Yi-Ting Chen, Chen-Syuan Lin
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Soil water index obtained by tank model is now commonly used in soil and sand disaster alarm system in Japan. Comparing with the rainfall trigging index in Taiwan, the tank model is easy to predict the slope water content on large-scale landslide. Therefore, this study aims to estimate the threshold value of large-scale landslide using the soil water index Sixteen typhoons and heavy rainfall events, were selected to establish the, to relationship between landslide event and soil water index. Finally, the proposed threshold values for landslides on country road No.89 are suggested in this study. The study results show that 95% landslide cases occurred in soil water index more than 125mm, and 30% of the more serious slope failure occurred in the soil water index is greater than 250mm. Beside, this study speculates when soil water index more than 250mm and the difference value between second tank and third tank less than -25mm, it leads to large-scale landslide more probably.Keywords: soil water index, tank model, landslide, threshold values
Procedia PDF Downloads 38723197 Maize Farmers’ Perception of Sharp Practices among Agro-Input Dealers in Ibadan/Ibarapa Agricultural Zone, Oyo State
Authors: Ademola A. Ladele, Peace I. Aburime
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Fake and substandard agricultural inputs pose a serious stumbling block to farm productivity and subsequently improved livelihood. There is, therefore, a need to pave ways for sustainable agriculture and self-sufficiency in food production by proffering solutions to this challenge. Maize farmers' perception of sharp practices among agro-input dealers in Ibadan/Ibarapa agricultural zone in Oyo state was therefore investigated. A multi-stage random sampling technique was used to select registered maize farmers in the Ibadan/Ibarapa agricultural zone of the Oyo State Agricultural Development Programme (OYSADEP). A structured questionnaire was used to collect information on the perception of sharp practices and the effects of sharp practices. A total of seventy-five maize farmers were interviewed. A focus group discussion was organized to identify ways of curbing sharp practices to complement the survey. Data were analyzed using descriptive statistics, Chi-square, and Pearson Product Moment Correlation (PPMC). Forms of sharp practices indicated were sales of expired fertilizers, expired pesticides, expired herbicides, underweight fertilizers, adulterated fertilizers, adulterated herbicides, packs containing broken seeds, infested seeds, lack of truth in labeling/wrong labels, manipulation of measuring scales, and false declaration of hecterages covered by tractor operators. The majority had unfavorable perception of agro-input dealers on sharp practices. A significant relationship was observed between respondents’ level of education and their perception of sharp practices. There were no significant relationships between respondents’ sex, marital status and religion, and their perception of sharp practices. A significant correlation exists between the forms of sharp practices and the perceived effect on agricultural production. It is concluded that the perceived effect of sharp practices was critical and the endemic culture of sharp practices prevailed in agro-input in Ibadan/Ibarapa agricultural zone. A standard regulatory system that will certify and monitor the quality of inputs should be put in place.Keywords: agricultural productivity, agro-input dealers, maize farmers, sharp practices
Procedia PDF Downloads 19823196 Co-Integration Model for Predicting Inflation Movement in Nigeria
Authors: Salako Rotimi, Oshungade Stephen, Ojewoye Opeyemi
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The maintenance of price stability is one of the macroeconomic challenges facing Nigeria as a nation. This paper attempts to build a co-integration multivariate time series model for inflation movement in Nigeria using data extracted from the abstract of statistics of the Central Bank of Nigeria (CBN) from 2008 to 2017. The Johansen cointegration test suggests at least one co-integration vector describing the long run relationship between Consumer Price Index (CPI), Food Price Index (FPI) and Non-Food Price Index (NFPI). All three series show increasing pattern, which indicates a sign of non-stationary in each of the series. Furthermore, model predictability was established with root-mean-square-error, mean absolute error, mean average percentage error, and Theil’s unbiased statistics for n-step forecasting. The result depicts that the long run coefficient of a consumer price index (CPI) has a positive long-run relationship with the food price index (FPI) and non-food price index (NFPI).Keywords: economic, inflation, model, series
Procedia PDF Downloads 24423195 Lee-Carter Mortality Forecasting Method with Dynamic Normal Inverse Gaussian Mortality Index
Authors: Funda Kul, İsmail Gür
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Pension scheme providers have to price mortality risk by accurate mortality forecasting method. There are many mortality-forecasting methods constructed and used in literature. The Lee-Carter model is the first model to consider stochastic improvement trends in life expectancy. It is still precisely used. Mortality forecasting is done by mortality index in the Lee-Carter model. It is assumed that mortality index fits ARIMA time series model. In this paper, we propose and use dynamic normal inverse gaussian distribution to modeling mortality indes in the Lee-Carter model. Using population mortality data for Italy, France, and Turkey, the model is forecasting capability is investigated, and a comparative analysis with other models is ensured by some well-known benchmarking criterions.Keywords: mortality, forecasting, lee-carter model, normal inverse gaussian distribution
Procedia PDF Downloads 36023194 Sharp Estimates of Oscillatory Singular Integrals with Rough Kernels
Authors: H. Al-Qassem, L. Cheng, Y. Pan
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In this paper, we establish sharp bounds for oscillatory singular integrals with an arbitrary real polynomial phase P. Our kernels are allowed to be rough both on the unit sphere and in the radial direction. We show that the bounds grow no faster than log (deg(P)), which is optimal and was first obtained by Parissis and Papadimitrakis for kernels without any radial roughness. Our results substantially improve many previously known results. Among key ingredients of our methods are an L¹→L² sharp estimate and using extrapolation.Keywords: oscillatory singular integral, rough kernel, singular integral, orlicz spaces, block spaces, extrapolation, L^{p} boundedness
Procedia PDF Downloads 45623193 Characterization of Performance of Blocks Produced from Dredged Sample
Authors: Adebayo B., Omotehinse A. O.
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The performance and characteristics of blocks produced from dredged sample was investigated. Blocks were produced using appropriate mixes of dredged sample and sharp sand. Some geotechnical properties (moisture content, grain size distribution) of the dredged sample (Igbokoda dredged sample) were determined using the British Standard. The physico-mechanical properties (water absorption, density and compressive strength) of blocks produced were evaluated. The dredged sample is classified as a silty material. Seven replacement levels of sharp sand were considered in the study (SS- Sharp Sand and DS – Dredged Sample) was done with constant amount of cement. 1- 85 % DS and 15 % SS, 2- 70 % DS and 30 % SS, 3- 55 % DS and 45 % SS, 4- 50 % DS and 50 % SS, 5- 45 % DS and 55 % SS, 6- 30 % DS and 70 % SS, 7- 15 % DS and 85 % SS and 8 – IS 100 % with cement; 9 – SS 100 % with cement) of different ages (7 days, 14 days, 21 days and 28 days) for the production of blocks. The compressive strength of the blocks produced ranges between 0.52 MPa to 3.0 MPa and considering the mixes, the highest compressive strength was found in mix of 15 % DS and 85 % SS.Keywords: dredge sample, silt, sharp sand, block, cement
Procedia PDF Downloads 36623192 Urban Design via Estimation Model for Traffic Index of Cities Based on an Artificial Intelligence
Authors: Seyed Sobhan Alvani, Mohammad Gohari
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By developing cities and increasing the population, traffic congestion has become a vital problem. Due to this crisis, urban designers try to present solutions to decrease this difficulty. On the other hand, predicting the model with perfect accuracy is essential for solution-providing. The current study presents a model based on artificial intelligence which can predict traffic index based on city population, growth rate, and area. The accuracy of the model was evaluated, which is acceptable and it is around 90%. Thus, urban designers and planners can employ it for predicting traffic index in the future to provide strategies.Keywords: traffic index, population growth rate, cities wideness, artificial neural network
Procedia PDF Downloads 4023191 Temperature Coefficients of the Refractive Index for Ge Film
Authors: Lingmao Xu, Hui Zhou
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Ge film is widely used in infrared optical systems. Because of the special requirements of space application, it is usually used in low temperature. The refractive index of Ge film is always changed with the temperature which has a great effect on the manufacture of high precision infrared optical film. Specimens of Ge single film were deposited at ZnSe substrates by EB-PVD method. During temperature range 80K ~ 300K, the transmittance of Ge single film within 2 ~ 15 μm were measured every 20K by PerkinElmer FTIR cryogenic testing system. By the full spectrum inversion method fitting, the relationship between refractive index and wavelength within 2 ~ 12μm at different temperatures was received. It can be seen the relationship consistent with the formula Cauchy, which can be fitted. Then the relationship between refractive index of the Ge film and temperature/wavelength was obtained by fitting method based on formula Cauchy. Finally, the designed value obtained by the formula and the measured spectrum were compared to verify the accuracy of the formula.Keywords: infrared optical film, low temperature, thermal refractive coefficient, Ge film
Procedia PDF Downloads 29823190 Number of Parameters of Anantharam's Model with Single-Input Single-Output Case
Authors: Kazuyoshi Mori
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In this paper, we consider the parametrization of Anantharam’s model within the framework of the factorization approach. In the parametrization, we investigate the number of required parameters of Anantharam’s model. We consider single-input single-output systems in this paper. By the investigation, we find three cases that are (1) there exist plants which require only one parameter and (2) two parameters, and (3) the number of parameters is at most three.Keywords: linear systems, parametrization, coprime factorization, number of parameters
Procedia PDF Downloads 21323189 MPC of Single Phase Inverter for PV System
Authors: Irtaza M. Syed, Kaamran Raahemifar
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This paper presents a model predictive control (MPC) of a utility interactive (UI) single phase inverter (SPI) for a photovoltaic (PV) system at residential/distribution level. The proposed model uses single-phase phase locked loop (PLL) to synchronize SPI with the grid and performs MPC control in a dq reference frame. SPI model consists of boost converter (BC), maximum power point tracking (MPPT) control, and a full bridge (FB) voltage source inverter (VSI). No PI regulators to tune and carrier and modulating waves are required to produce switching sequence. Instead, the operational model of VSI is used to synthesize sinusoidal current and track the reference. Model is validated using a three kW PV system at the input of UI-SPI in Matlab/Simulink. Implementation and results demonstrate simplicity and accuracy, as well as reliability of the model.Keywords: phase locked loop, voltage source inverter, single phase inverter, model predictive control, Matlab/Simulink
Procedia PDF Downloads 53223188 Ultrafast Transistor Laser Containing Graded Index Separate Confinement Heterostructure
Authors: Mohammad Hosseini
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Ultrafast transistor laser investigated here has the graded index separate confinement heterostructure (GRIN-SCH) in its base region. Resonance-free optical frequency response with -3dB bandwidth of more than 26 GHz has been achieved for a single quantum well transistor laser by using graded index layers of AlξGa1-ξAs (ξ: 0.1→0) on the left side of the quantum well and AlξGa1-ξAs (ξ: 0.05→0) in the right side of quantum well. All required parameters, including quantum well and base transit time, optical confinement factor and spontaneous recombination lifetime, have been calculated using a self-consistent charge control model.Keywords: transistor laser, ultrafast, GRIN-SCH, -3db optical bandwidth, AlξGa1-ξAs
Procedia PDF Downloads 15423187 Compression Index Estimation by Water Content and Liquid Limit and Void Ratio Using Statistics Method
Authors: Lizhou Chen, Abdelhamid Belgaid, Assem Elsayed, Xiaoming Yang
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Compression index is essential in foundation settlement calculation. The traditional method for determining compression index is consolidation test which is expensive and time consuming. Many researchers have used regression methods to develop empirical equations for predicting compression index from soil properties. Based on a large number of compression index data collected from consolidation tests, the accuracy of some popularly empirical equations were assessed. It was found that primary compression index is significantly overestimated in some equations while it is underestimated in others. The sensitivity analyses of soil parameters including water content, liquid limit and void ratio were performed. The results indicate that the compression index obtained from void ratio is most accurate. The ANOVA (analysis of variance) demonstrates that the equations with multiple soil parameters cannot provide better predictions than the equations with single soil parameter. In other words, it is not necessary to develop the relationships between compression index and multiple soil parameters. Meanwhile, it was noted that secondary compression index is approximately 0.7-5.0% of primary compression index with an average of 2.0%. In the end, the proposed prediction equations using power regression technique were provided that can provide more accurate predictions than those from existing equations.Keywords: compression index, clay, settlement, consolidation, secondary compression index, soil parameter
Procedia PDF Downloads 16223186 Flexural Toughness of Fiber Reinforced Reactive Powder Concrete (RPC)
Authors: S. Yousefi Oderji, B. Chen
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According to the ASTM C1018 toughness index method, the single and combined toughness effects of copper coated steel fiber and polypropylene (pp) fiber on reactive powder concrete (RPC) were investigated. Through flexural toughness test of RPC with different fiber volume dosages, the corresponding load-deflection curves were also drawn. Test results indicate that the binary combination of fibers provide the best flexural toughness, and improve the post-peak load-deflection characteristics of RPC. However, the single effect of pp fibers was not pronounced on improving the flexural toughness of RPC.Keywords: RPC, PP, flexural toughness, toughness index
Procedia PDF Downloads 33723185 Modeling Aeration of Sharp Crested Weirs by Using Support Vector Machines
Authors: Arun Goel
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The present paper attempts to investigate the prediction of air entrainment rate and aeration efficiency of a free over-fall jets issuing from a triangular sharp crested weir by using regression based modelling. The empirical equations, support vector machine (polynomial and radial basis function) models and the linear regression techniques were applied on the triangular sharp crested weirs relating the air entrainment rate and the aeration efficiency to the input parameters namely drop height, discharge, and vertex angle. It was observed that there exists a good agreement between the measured values and the values obtained using empirical equations, support vector machine (Polynomial and rbf) models, and the linear regression techniques. The test results demonstrated that the SVM based (Poly & rbf) model also provided acceptable prediction of the measured values with reasonable accuracy along with empirical equations and linear regression techniques in modelling the air entrainment rate and the aeration efficiency of a free over-fall jets issuing from triangular sharp crested weir. Further sensitivity analysis has also been performed to study the impact of input parameter on the output in terms of air entrainment rate and aeration efficiency.Keywords: air entrainment rate, dissolved oxygen, weir, SVM, regression
Procedia PDF Downloads 43623184 Development of Groundwater Management Model Using Groundwater Sustainability Index
Authors: S. S. Rwanga, J. M. Ndambuki, Y. Woyessa
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Development of a groundwater management model is an important step in the exploitation and management of any groundwater aquifer as it assists in the long-term sustainable planning of the resource. The current study was conducted in Central Limpopo province of South Africa with the overall objective of determining how much water can be withdrawn from the aquifer without producing nonreversible impacts on the groundwater quantity, hence developing a model which can sustainably protect the aquifer. The development was done through the computation of Groundwater Sustainability Index (GSI). Values of GSI close to unity and above indicated overexploitation. In this study, an index of 0.8 was considered as overexploitation. The results indicated that there is potential for higher abstraction rates compared to the current abstraction rates. GSI approach can be used in the management of groundwater aquifer to sustainably develop the resource and also provides water managers and policy makers with fundamental information on where future water developments can be carried out.Keywords: development, groundwater, groundwater sustainability index, model
Procedia PDF Downloads 16923183 Utility Assessment Model for Wireless Technology in Construction
Authors: Yassir AbdelRazig, Amine Ghanem
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Construction projects are information intensive in nature and involve many activities that are related to each other. Wireless technologies can be used to improve the accuracy and timeliness of data collected from construction sites and shares it with appropriate parties. Nonetheless, the construction industry tends to be conservative and shows hesitation to adopt new technologies. A main concern for owners, contractors or any person in charge on a job site is the cost of the technology in question. Wireless technologies are not cheap. There are a lot of expenses to be taken into consideration, and a study should be completed to make sure that the importance and savings resulting from the usage of this technology is worth the expenses. This research attempts to assess the effectiveness of using the appropriate wireless technologies based on criteria such as performance, reliability, and risk. The assessment is based on a utility function model that breaks down the selection issue into alternatives attribute. Then the attributes are assigned weights and single attributes are measured. Finally, single attribute are combined to develop one single aggregate utility index for each alternative.Keywords: analytic hierarchy process, decision theory, utility function, wireless technologies
Procedia PDF Downloads 34223182 The Effects of Kicking Leg Preference on the Bilateral Balance Ability Asymmetries in Collegian Football Players
Authors: Mehmet Yildiz, Mehmet Kale
Abstract:
The primary aim of the present study was to identify the bilateral balance asymmetries when comparing the dominant (DL) vs. the non-dominant leg (NDL) in the collegian soccer players. The secondary aim was to compare the inter-limb asymmetry index (ASI) when differentiating by kicking preference (right-dominant vs. left-dominant). 34 right-dominant leg (RightDL) (age:21.12±1.85, height:174.50±5.18, weight:69.42±6.86) and 23 left-dominant leg (LeftDL), (age:21.70±2.03, height:176.2±6.27, weight:68.73±5.96) collegian football players were tested for bilateral static and dynamic balance. Balance ability was assessed by measuring centre of pressure deviation on a single leg. Single leg static and dynamic balance scores and inter-limb asymmetry index (ASI) were determined. Student t tests were used for the comparison of dominant and nondominant leg balance scores and RightDL and LeftDL football players’ inter-limb asymmetry index of the balance scores. The results showed that there were significant differences in the dynamic balance scores in favour of the nondominant leg, (DL:738±211 vs. NDL:606±226, p < 0.01). Also, it has been seen that LeftDL players have significantly higher inter-limb asymmetry index when compared with rightDL players for both static (rightDL:-7.07±94.91 vs. leftDL:-183.19±354.05, p < 0.01) and dynamic (rightDL: 1.73±49.65 vs. leftDL:27.08±23.34, p < 0.05) balance scores. In conclusion, bilateral dynamic balance asymmetries may be affected using single leg predominantly in the mobilization workouts. Because of having higher inter-limb asymmetry index, left-dominant leg players may be screened and trained to minimize balance asymmetry.Keywords: bilateral balance, asymmetries, dominant leg, leg preference
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