Search results for: partial least squares
963 A Hyperexponential Approximation to Finite-Time and Infinite-Time Ruin Probabilities of Compound Poisson Processes
Authors: Amir T. Payandeh Najafabadi
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This article considers the problem of evaluating infinite-time (or finite-time) ruin probability under a given compound Poisson surplus process by approximating the claim size distribution by a finite mixture exponential, say Hyperexponential, distribution. It restates the infinite-time (or finite-time) ruin probability as a solvable ordinary differential equation (or a partial differential equation). Application of our findings has been given through a simulation study.Keywords: ruin probability, compound poisson processes, mixture exponential (hyperexponential) distribution, heavy-tailed distributions
Procedia PDF Downloads 341962 Supplementation of Mannan Oligosaccharides in Guinea Pigs: Mortality and Growth Performance
Authors: C. Minguez, J. Bueso-Rodenas, C. Ibanez, A. Calvo
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Mannan oligosaccharides (MOS) is one of the prebiotic most used in livestock nutrition. In this research, the effect of MOS dietary supplementation on growth performance and mortality in meat guinea pigs were studied. Three different experimental groups were compared: Control group (no additives); MOS 1 (1.5 g kg−1); MOS 2 (2 g kg−1). Guinea pigs were housed in 15 collective cages (n = 50 animals in each trial; 10 animals per cage). The young guinea pigs were weaning at day 28 and individually identified by a little ear tag. The fattening period was 49 days. Guinea pigs in both groups were fed ad libitum, with a standard commercial pellet diet (10 MJ of digestible energy/kg, 17% crude protein, 11% crude fiber, and 4.5% crude fat) and alfalfa (Medicago sativa) as forage. Growth traits, including body weight (BW), average daily gain (ADG), feed intake (FI), and feed conversion ratio (FCR), were measured weekly. On day 74, the animals were slaughtered. Contrasts between groups were obtained by calculated generalized least squares values. Mortality were evaluated by Fisher's exact test. Between MOS groups no significant differences were observed for growth traits and mortality. However, significant differences against the control group were observed for traits studied (pvalue < 0.05). In conclusion, the use of MOS could be a good prebiotic supplement to raise guinea pigs because it MOS has shown positive effects in growth traits and immune response in animals.Keywords: guinea pig, growth, mannan oligosaccharides, mortality
Procedia PDF Downloads 139961 The Determinants of Financing to Deposit Ratio of Islamic Bank in Malaysia
Authors: Achsania Hendratmi, Puji Sucia Sukmaningrum, Fatin Fadhilah Hasib, Nisful Laila
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The research aimed to know the influence of Capital Adequacy Ratio (CAR), Return on Assets (ROA) and Size of the Financing to Deposit Ratio (FDR) Islamic Banks in Malaysia by using eleven Islamic Banks in Indonesia and fifteen Islamic Banks in Malaysia in the period 2012 to 2016 as samples. The research used a quantitative approach method, and the analysis technique used multiple linear regression. Based on the result of t-test (partial), CAR, ROA and size significantly affect of FDR. While the results of f-test (simultaneous) showed that CAR, ROA and Size significant effect on FDR.Keywords: capital adequacy ratio, financing to deposit ratio, return on assets, size
Procedia PDF Downloads 339960 Simulation of I–V Characteristics of Lateral PIN Diode on Polysilicon Films
Authors: Abdelaziz Rabhi, Mohamed Amrani, Abderrazek Ziane, Nabil Belkadi, Abdelraouf Hocini
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In this paper, a bedimensional simulation program of the electric characteristics of reverse biased lateral polysilicon PIN diode is presented. In this case we have numerically solved the system of partial differential equations formed by Poisson's equation and both continuity equations that take into account the effect of impact ionization. Therefore we will obtain the current-voltage characteristics (I-V) of the reverse-biased structure which may include the effect of breakdown.The geometrical model assumes that the polysilicon layer is composed by a succession of defined mean grain size crystallites, separated by lateral grain boundaries which are parallel to the metallurgic junction.Keywords: breakdown, polycrystalline silicon, PIN, grain, impact ionization
Procedia PDF Downloads 381959 Accelerated Structural Reliability Analysis under Earthquake-Induced Tsunamis by Advanced Stochastic Simulation
Authors: Sai Hung Cheung, Zhe Shao
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Recent earthquake-induced tsunamis in Padang, 2004 and Tohoku, 2011 brought huge losses of lives and properties. Maintaining vertical evacuation systems is the most crucial strategy to effectively reduce casualty during the tsunami event. Thus, it is of our great interest to quantify the risk to structural dynamic systems due to earthquake-induced tsunamis. Despite continuous advancement in computational simulation of the tsunami and wave-structure interaction modeling, it still remains computationally challenging to evaluate the reliability (or its complement failure probability) of a structural dynamic system when uncertainties related to the system and its modeling are taken into account. The failure of the structure in a tsunami-wave-structural system is defined as any response quantities of the system exceeding specified thresholds during the time when the structure is subjected to dynamic wave impact due to earthquake-induced tsunamis. In this paper, an approach based on a novel integration of the Subset Simulation algorithm and a recently proposed moving least squares response surface approach for stochastic sampling is proposed. The effectiveness of the proposed approach is discussed by comparing its results with those obtained from the Subset Simulation algorithm without using the response surface approach.Keywords: response surface model, subset simulation, structural reliability, Tsunami risk
Procedia PDF Downloads 383958 Dual Solutions in Mixed Convection Boundary Layer Flow: A Stability Analysis
Authors: Anuar Ishak
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The mixed convection stagnation point flow toward a vertical plate is investigated. The external flow impinges normal to the heated plate and the surface temperature is assumed to vary linearly with the distance from the stagnation point. The governing partial differential equations are transformed into a set of ordinary differential equations, which are then solved numerically using MATLAB routine boundary value problem solver bvp4c. Numerical results show that dual solutions are possible for a certain range of the mixed convection parameter. A stability analysis is performed to determine which solution is linearly stable and physically realizable.Keywords: dual solutions, heat transfer, mixed convection, stability analysis
Procedia PDF Downloads 390957 Impact of Tobacco Control Policy to Cancer Mortalities in South Africa
Authors: Cyprian M. Mostert
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This paper investigates the effectiveness of tobacco control policy (TCP) in averting cancer mortalities in both educated and uneducated segments of the South African population. A two-stage least squares model (2SLS) was used covering the period 2009-2013. The results show that the TCP caused a 26 percent average decrease in cancer mortalities in both educated and uneducated segment of the population. However, limiting the sales of cheap and illegal tobacco cigarettes is necessary for advancing the effectiveness of TCP in averting cancer mortalities in the uneducated population — as the paper noted an insignificant decrease in cancer mortalities in 2012-2013 due to the presence of cheaper cigarettes. The paper also discovered evidence of persisting tobacco purchases of branded cigarettes in the educated population group which limited the effectiveness of TCP in 2009-2011. Hikes in real tobacco tax to a 0.8 USD price level in 2012 limited tobacco consumption in the educated group resulting in a 29 percent decrease in cancer mortalities. Other developing countries may learn from the South African case and strive to limit the sales of cheap illegal cigarettes while hiking real tobacco tax of branded cigarettes as a key strategy to improve cancer deaths across educated and uneducated population groups.Keywords: cancer, health policy, health system, tobacco tax
Procedia PDF Downloads 145956 Geopotential Models Evaluation in Algeria Using Stochastic Method, GPS/Leveling and Topographic Data
Authors: M. A. Meslem
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For precise geoid determination, we use a reference field to subtract long and medium wavelength of the gravity field from observations data when we use the remove-compute-restore technique. Therefore, a comparison study between considered models should be made in order to select the optimal reference gravity field to be used. In this context, two recent global geopotential models have been selected to perform this comparison study over Northern Algeria. The Earth Gravitational Model (EGM2008) and the Global Gravity Model (GECO) conceived with a combination of the first model with anomalous potential derived from a GOCE satellite-only global model. Free air gravity anomalies in the area under study have been used to compute residual data using both gravity field models and a Digital Terrain Model (DTM) to subtract the residual terrain effect from the gravity observations. Residual data were used to generate local empirical covariance functions and their fitting to the closed form in order to compare their statistical behaviors according to both cases. Finally, height anomalies were computed from both geopotential models and compared to a set of GPS levelled points on benchmarks using least squares adjustment. The result described in details in this paper regarding these two models has pointed out a slight advantage of GECO global model globally through error degree variances comparison and ground-truth evaluation.Keywords: quasigeoid, gravity aomalies, covariance, GGM
Procedia PDF Downloads 137955 The Quality of Public Space in Mexico City: Current State and Trends
Authors: Mildred Moreno Villanueva
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Public space is essential to strengthen the social and urban fabric and the social cohesion; there lies the importance of its study. Hence, the aim of this paper is to analyze the quality of public space in the XXI century in both quantitative and qualitative terms. In this article, the concept of public space includes open spaces such as parks, public squares and walking areas. To make this analysis we take Mexico City as the case study. It has a population of nearly 9 million inhabitants and it is composed of sixteen boroughs. For this analysis, we consider both, existing public spaces and the government intervention for building and improvement of new and existent public spaces. Results show that on the one hand, quantitatively there is not an equitable distribution of public spaces because of both, the growth of the city itself, as well as for the absence of political will to create public spaces. Another factor is the evolution of this city, which has been growing merely in a 'patched pattern', where public space has played no role at all with a total absence of urban design. On the other hand, qualitatively, even the boroughs with the most public spaces have not shown interest in making these spaces qualitatively inclusive and open to the general population aiming for integration. Therefore, urban projects that privatize public space seem to be the rule, rather than a rehabilitation effort of the existent public spaces. Hence, state intervention should reinforce its role as an agent of social change acting in the benefit of the majority of the inhabitants with the promotion of more inclusive public spaces.Keywords: exclusion, inclusion, Mexico City, public space
Procedia PDF Downloads 618954 Hypergeometric Solutions to Linear Nonhomogeneous Fractional Equations with Spherical Bessel Functions of the First Kind
Authors: Pablo Martin, Jorge Olivares, Fernando Maass
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The use of fractional derivatives to different problems in Engineering and Physics has been increasing in the last decade. For this reason, we have here considered partial derivatives when the integral is a spherical Bessel function of the first kind in both regular and modified ones simple initial conditions have been also considered. In this way, the solution has been found as a combination of hypergeometric functions. The case of a general rational value for α of the fractional derivative α has been solved in a general way for alpha between zero and two. The modified spherical Bessel functions of the first kind have been also considered and how to go from the regular case to the modified one will be also shown.Keywords: caputo fractional derivatives, hypergeometric functions, linear differential equations, spherical Bessel functions
Procedia PDF Downloads 325953 Screening for Larvicidal Activity of Aqueous and Ethanolic Extracts of Fourteen Selected Plants and Formulation of a Larvicide against Aedes aegypti (Linn.) and Aedes albopictus (Skuse) Larvae
Authors: Michael Russelle S. Alvarez, Noel S. Quiming, Francisco M. Heralde
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This study aims to: a) obtain ethanolic (95% EtOH) and aqueous extracts of Selaginella elmeri, Christella dentata, Elatostema sinnatum, Curculigo capitulata, Euphorbia hirta, Murraya koenigii, Alpinia speciosa, Cymbopogon citratus, Eucalyptus globulus, Jatropha curcas, Psidium guajava, Gliricidia sepium, Ixora coccinea and Capsicum frutescens and screen them for larvicidal activities against Aedes aegypti (Linn.) and Aedes albopictus (Skuse) larvae; b) to fractionate the most active extract and determine the most active fraction; c) to determine the larvicidal properties of the most active extract and fraction against by computing their percentage mortality, LC50, and LC90 after 24 and 48 hours of exposure; and d) to determine the nature of the components of the active extracts and fractions using phytochemical screening. Ethanolic (95% EtOH) and aqueous extracts of the selected plants will be screened for potential larvicidal activity against Ae. aegypti and Ae. albopictus using standard procedures and 1% malathion and a Piper nigrum based ovicide-larvicide by the Department of Science and Technology as positive controls. The results were analyzed using One-Way ANOVA with Tukey’s and Dunnett’s test. The most active extract will be subjected to partial fractionation using normal-phase column chromatography, and the fractions subsequently screened to determine the most active fraction. The most active extract and fraction were subjected to dose-response assay and probit analysis to determine the LC50 and LC90 after 24 and 48 hours of exposure. The active extracts and fractions will be screened for phytochemical content. The ethanolic extracts of C. citratus, E. hirta, I. coccinea, G. sepium, M. koenigii, E globulus, J. curcas and C. frutescens exhibited significant larvicidal activity, with C. frutescens being the most active. After fractionation, the ethyl acetate fraction was found to be the most active. Phytochemical screening of the extracts revealed the presence of alkaloids, tannins, indoles and steroids. A formulation using talcum powder–300 mg fraction per 1 g talcum powder–was made and again tested for larvicidal activity. At 2 g/L, the formulation proved effective in killing all of the test larvae after 24 hours.Keywords: larvicidal activity screening, partial purification, dose-response assay, capsicum frutescens
Procedia PDF Downloads 329952 Analytical Soliton Solutions of the Fractional Jaulent-Miodek System
Authors: Sajeda Elbashabsheh, Kamel Al-Khaled
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This paper applies a modified Laplace Adomian decomposition method to solve the time-fractional JaulentMiodek system. The method produce convergent series solutions with easily compatible components. This paper considers the Caputo fractional derivative. The effectiveness and applicability of the method are demonstrated by comparing its results with those of prior studies. Results are presented in tables and figures. These solutions might be imperative and significant for the explanation of some practical physical phenomena. All computations and figures in the work are done using MATHEMATICA. The numerical results demonstrate that the current methods are effective, reliable, and simple to i implement for nonlinear fractional partial differential equations.Keywords: approximate solutions, Jaulent-Miodek system, Adomian decomposition method, solitons
Procedia PDF Downloads 44951 Magnetohydrodynamic Flow over an Exponentially Stretching Sheet
Authors: Raj Nandkeolyar, Precious Sibanda
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The flow of a viscous, incompressible, and electrically conducting fluid under the influence of aligned magnetic field acting along the direction of fluid flow over an exponentially stretching sheet is investigated numerically. The nonlinear partial differential equations governing the flow model is transformed to a set of nonlinear ordinary differential equations using suitable similarity transformation and the solution is obtained using a local linearization method followed by the Chebyshev spectral collocation method. The effects of various parameters affecting the flow and heat transfer as well as the induced magnetic field are discussed using suitable graphs and tables.Keywords: aligned magnetic field, exponentially stretching sheet, induced magnetic field, magnetohydrodynamic flow
Procedia PDF Downloads 454950 Determinants of Aggregate Electricity Consumption in Ghana: A Multivariate Time Series Analysis
Authors: Renata Konadu
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In Ghana, electricity has become the main form of energy which all sectors of the economy rely on for their businesses. Therefore, as the economy grows, the demand and consumption of electricity also grow alongside due to the heavy dependence on it. However, since the supply of electricity has not increased to match the demand, there has been frequent power outages and load shedding affecting business performances. To solve this problem and advance policies to secure electricity in Ghana, it is imperative that those factors that cause consumption to increase be analysed by considering the three classes of consumers; residential, industrial and non-residential. The main argument, however, is that, export of electricity to other neighbouring countries should be included in the electricity consumption model and considered as one of the significant factors which can decrease or increase consumption. The author made use of multivariate time series data from 1980-2010 and econometric models such as Ordinary Least Squares (OLS) and Vector Error Correction Model. Findings show that GDP growth, urban population growth, electricity exports and industry value added to GDP were cointegrated. The results also showed that there is unidirectional causality from electricity export and GDP growth and Industry value added to GDP to electricity consumption in the long run. However, in the short run, there was found to be a directional causality among all the variables and electricity consumption. The results have useful implication for energy policy makers especially with regards to electricity consumption, demand, and supply.Keywords: electricity consumption, energy policy, GDP growth, vector error correction model
Procedia PDF Downloads 437949 Separate Collection System of Recyclables and Biowaste Treatment and Utilization in Metropolitan Area Finland
Authors: Petri Kouvo, Aino Kainulainen, Kimmo Koivunen
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Separate collection system for recyclable wastes in the Helsinki region was ranked second best of European capitals. The collection system includes paper, cardboard, glass, metals and biowaste. Residual waste is collected and used in energy production. The collection system excluding paper is managed by the Helsinki Region Environmental Services HSY, a public organization owned by four municipalities (Helsinki, Espoo, Kauniainen and Vantaa). Paper collection is handled by the producer responsibility scheme. The efficiency of the collection system in the Helsinki region relies on a good coverage of door-to-door-collection. All properties with 10 or more dwelling units are required to source separate biowaste and cardboard. This covers about 75% of the population of the area. The obligation is extended to glass and metal in properties with 20 or more dwelling units. Other success factors include public awareness campaigns and a fee system that encourages recycling. As a result of waste management regulations for source separation of recyclables and biowaste, nearly 50 percent of recycling rate of household waste has been reached. For households and small and medium size enterprises, there is a sorting station fleet of five stations available. More than 50 percent of wastes received at sorting stations is utilized as material. The separate collection of plastic packaging in Finland will begin in 2016 within the producer responsibility scheme. HSY started supplementing the national bring point system with door-to-door-collection and pilot operations will begin in spring 2016. The result of plastic packages pilot project has been encouraging. Until the end of 2016, over 3500 apartment buildings have been joined the piloting, and more than 1800 tons of plastic packages have been collected separately. In the summer 2015 a novel partial flow digestion process combining digestion and tunnel composting was adopted for source separated household and commercial biowaste management. The product gas form digestion process is converted in to heat and electricity in piston engine and organic Rankine cycle process with very high overall efficiency. This paper describes the efficient collection system and discusses key success factors as well as main obstacles and lessons learned as well as the partial flow process for biowaste management.Keywords: biowaste, HSY, MSW, plastic packages, recycling, separate collection
Procedia PDF Downloads 217948 Application of the Discrete Rationalized Haar Transform to Distributed Parameter System
Authors: Joon-Hoon Park
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In this paper the rationalized Haar transform is applied for distributed parameter system identification and estimation. A distributed parameter system is a dynamical and mathematical model described by a partial differential equation. And system identification concerns the problem of determining mathematical models from observed data. The Haar function has some disadvantages of calculation because it contains irrational numbers, for these reasons the rationalized Haar function that has only rational numbers. The algorithm adopted in this paper is based on the transform and operational matrix of the rationalized Haar function. This approach provides more convenient and efficient computational results.Keywords: distributed parameter system, rationalized Haar transform, operational matrix, system identification
Procedia PDF Downloads 509947 Speckle Noise Reduction Using Anisotropic Filter Based on Wavelets
Authors: Kritika Bansal, Akwinder Kaur, Shruti Gujral
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In this paper, the approach of denoising is solved by using a new hybrid technique which associates the different denoising methods. Wavelet thresholding and anisotropic diffusion filter are the two different filters in our hybrid techniques. The Wavelet thresholding removes the noise by removing the high frequency components with lesser edge preservation, whereas an anisotropic diffusion filters is based on partial differential equation, (PDE) to remove the speckle noise. This PDE approach is used to preserve the edges and provides better smoothing. So our new method proposes a combination of these two filtering methods which performs better results in terms of peak signal to noise ratio (PSNR), coefficient of correlation (COC) and equivalent no of looks (ENL).Keywords: denoising, anisotropic diffusion filter, multiplicative noise, speckle, wavelets
Procedia PDF Downloads 512946 Magnetohydrodynamic 3D Maxwell Fluid Flow Towards a Horizontal Stretched Surface with Convective Boundary Conditions
Authors: M. Y. Malika, Farzana, Abdul Rehman
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The study deals with the steady, 3D MHD boundary layer flow of a non-Newtonian Maxwell fluid flow due to a horizontal surface stretched exponentially in two lateral directions. The temperature at the boundary is assumed to be distributed exponentially and possesses convective boundary conditions. The governing nonlinear system of partial differential equations along with associated boundary conditions is simplified using a suitable transformation and the obtained set of ordinary differential equations is solved through numerical techniques. The effects of important involved parameters associated with fluid flow and heat flux are shown through graphs.Keywords: boundary layer flow, exponentially stretched surface, Maxwell fluid, numerical solution
Procedia PDF Downloads 588945 The Effect of Book-Tax Conformity on Audit Quality: Evidence from Canada
Authors: Yosra Makni Fourati, Sana Masmoudi Mardassi
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This paper investigates the effect of Book-tax conformity on audit quality regarding the proxies of audit fees, auditors’ industry specialization and audit report lag. Using a sample of Canadian firms listed on the Toronto Stock Exchange spanning the years 2006- 2016, we applied an Ordinary Least Squares (OLS) regression to test hypotheses of this research. The authors find that higher Book-tax conformity leads to lower audit fees. They also provide evidence that there is a negative association between Book-tax conformity and auditors’ industry specialization, whereas there is a positive association between Book-tax conformity and audit report lag. Overall, the findings are prominent to better understanding the effect of Book-tax conformity on audit quality and are relevant for academic researchers, practitioners, and regulators. As the paper investigates the relationship of Book-tax conformity and audit quality using a sample of Canadian firms, it brings original insights regarding the importance of audit fees and Book-tax conformity. In addition, it considers the role of auditor’s industry specialization in the relation between audit quality and Book-tax conformity by considering a sample listed on the Toronto Stock Exchange. This paper contributes to the existing literature by highlighting the Canadian setting, to our best knowledge. In addition, our results are prominent to the auditing literature as they introduce a different determinant of auditors’ industry specialization and audit report lag.Keywords: audit fees, auditors' industry specialization, audit report lag, book-tax conformity
Procedia PDF Downloads 158944 Compressed Natural Gas (CNG) Injector Research for Dual Fuel Engine
Authors: Adam Majczak, Grzegorz Barański, Marcin Szlachetka
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Environmental considerations necessitate the search for new energy sources. One of the available solutions is a partial replacement of diesel fuel by compressed natural gas (CNG) in the compression ignition engines. This type of the engines is used mainly in vans and trucks. These units are also gaining more and more popularity in the passenger car market. In Europe, this part of the market share reaches 50%. Diesel engines are also used in industry in such vehicles as ship or locomotives. Diesel engines have higher emissions of nitrogen oxides in comparison to spark ignition engines. This can be currently limited by optimizing the combustion process and the use of additional systems such as exhaust gas recirculation or AdBlue technology. As a result of the combustion process of diesel fuel also particulate matter (PM) that are harmful to the human health are emitted. Their emission is limited by the use of a particulate filter. One of the method for toxic components emission reduction may be the use of liquid gas fuel such as propane and butane (LPG) or compressed natural gas (CNG). In addition to the environmental aspects, there are also economic reasons for the use of gaseous fuels to power diesel engines. A total or partial replacement of diesel gas is possible. Depending on the used technology and the percentage of diesel fuel replacement, it is possible to reduce the content of nitrogen oxides in the exhaust gas even by 30%, particulate matter (PM) by 95 % carbon monoxide and by 20%, in relation to original diesel fuel. The research object is prototype gas injector designed for direct injection of compressed natural gas (CNG) in compression ignition engines. The construction of the injector allows for it positioning in the glow plug socket, so that the gas is injected directly into the combustion chamber. The cycle analysis of the four-cylinder Andoria ADCR engine with a capacity of 2.6 dm3 for different crankshaft rotational speeds allowed to determine the necessary time for fuel injection. Because of that, it was possible to determine the required mass flow rate of the injector, for replacing as much of the original fuel by gaseous fuel. To ensure a high value of flow inside the injector, supply pressure equal to 1 MPa was applied. High gas supply pressure requires high value of valve opening forces. For this purpose, an injector with hydraulic control system, using a liquid under pressure for the opening process was designed. On the basis of air pressure measurements in the flow line after the injector, the analysis of opening and closing of the valve was made. Measurements of outflow mass of the injector were also carried out. The results showed that the designed injector meets the requirements necessary to supply ADCR engine by the CNG fuel.Keywords: CNG, diesel engine, gas flow, gas injector
Procedia PDF Downloads 493943 The Impact of Public Open Space System on Housing Price in Chicago
Authors: Si Chen, Le Zhang, Xian He
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The research explored the influences of public open space system on housing price through hedonic models, in order to support better open space plans and economic policies. We have three initial hypotheses: 1) public open space system has an overall positive influence on surrounding housing prices. 2) Different public open space types have different levels of influence on motivating surrounding housing prices. 3) Walking and driving accessibilities from property to public open spaces have different statistical relation with housing prices. Cook County, Illinois, was chosen to be a study area since data availability, sufficient open space types, and long-term open space preservation strategies. We considered the housing attributes, driving and walking accessibility scores from houses to nearby public open spaces, and driving accessibility scores to hospitals as influential features and used real housing sales price in 2010 as a dependent variable in the built hedonic model. Through ordinary least squares (OLS) regression analysis, General Moran’s I analysis and geographically weighted regression analysis, we observed the statistical relations between public open spaces and housing sale prices in the three built hedonic models and confirmed all three hypotheses.Keywords: hedonic model, public open space, housing sale price, regression analysis, accessibility score
Procedia PDF Downloads 133942 Torrefaction of Biomass Pellets: Modeling of the Process in a Fixed Bed Reactor
Authors: Ekaterina Artiukhina, Panagiotis Grammelis
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Torrefaction of biomass pellets is considered as a useful pretreatment technology in order to convert them into a high quality solid biofuel that is more suitable for pyrolysis, gasification, combustion and co-firing applications. In the course of torrefaction the temperature varies across the pellet, and therefore chemical reactions proceed unevenly within the pellet. However, the uniformity of the thermal distribution along the pellet is generally assumed. The torrefaction process of a single cylindrical pellet is modeled here, accounting for heat transfer coupled with chemical kinetics. The drying sub-model was also introduced. The non-stationary process of wood pellet decomposition is described by the system of non-linear partial differential equations over the temperature and mass. The model captures well the main features of the experimental data.Keywords: torrefaction, biomass pellets, model, heat, mass transfer
Procedia PDF Downloads 480941 Urban Energy Demand Modelling: Spatial Analysis Approach
Authors: Hung-Chu Chen, Han Qi, Bauke de Vries
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Energy consumption in the urban environment has attracted numerous researches in recent decades. However, it is comparatively rare to find literary works which investigated 3D spatial analysis of urban energy demand modelling. In order to analyze the spatial correlation between urban morphology and energy demand comprehensively, this paper investigates their relation by using the spatial regression tool. In addition, the spatial regression tool which is applied in this paper is ordinary least squares regression (OLS) and geographically weighted regression (GWR) model. Normalized Difference Built-up Index (NDBI), Normalized Difference Vegetation Index (NDVI), and building volume are explainers of urban morphology, which act as independent variables of Energy-land use (E-L) model. NDBI and NDVI are used as the index to describe five types of land use: urban area (U), open space (O), artificial green area (G), natural green area (V), and water body (W). Accordingly, annual electricity, gas demand and energy demand are dependent variables of the E-L model. Based on the analytical result of E-L model relation, it revealed that energy demand and urban morphology are closely connected and the possible causes and practical use are discussed. Besides, the spatial analysis methods of OLS and GWR are compared.Keywords: energy demand model, geographically weighted regression, normalized difference built-up index, normalized difference vegetation index, spatial statistics
Procedia PDF Downloads 148940 Assessing Level of Pregnancy Rate and Milk Yield in Indian Murrah Buffaloes
Authors: V. Jamuna, A. K. Chakravarty, C. S. Patil, Vijay Kumar, M. A. Mir, Rakesh Kumar
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Intense selection of buffaloes for milk production at organized herds of the country without giving due attention to fertility traits viz. pregnancy rate has lead to deterioration in their performances. Aim of study is to develop an optimum model for predicting pregnancy rate and to assess the level of pregnancy rate with respect to milk production Murrah buffaloes. Data pertaining to 1224 lactation records of Murrah buffaloes spread over a period 21 years were analyzed and it was observed that pregnancy rate depicted negative phenotypic association with lactation milk yield (-0.08 ± 0.04). For developing optimum model for pregnancy rate in Murrah buffaloes seven simple and multiple regression models were developed. Among the seven models, model II having only Service period as an independent reproduction variable, was found to be the best prediction model, based on the four statistical criterions (high coefficient of determination (R 2), low mean sum of squares due to error (MSSe), conceptual predictive (CP) value, and Bayesian information criterion (BIC). For standardizing the level of fertility with milk production, pregnancy rate was classified into seven classes with the increment of 10% in all parities, life time and their corresponding average pregnancy rate in relation to the average lactation milk yield (MY).It was observed that to achieve around 2000 kg MY which can be considered optimum for Indian Murrah buffaloes, level of pregnancy rate should be in between 30-50%.Keywords: life time, pregnancy rate, production, service period, standardization
Procedia PDF Downloads 635939 Dynamic Fault Diagnosis for Semi-Batch Reactor Under Closed-Loop Control via Independent RBFNN
Authors: Abdelkarim M. Ertiame, D. W. Yu, D. L. Yu, J. B. Gomm
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In this paper, a new robust fault detection and isolation (FDI) scheme is developed to monitor a multivariable nonlinear chemical process called the Chylla-Haase polymerization reactor when it is under the cascade PI control. The scheme employs a radial basis function neural network (RBFNN) in an independent mode to model the process dynamics and using the weighted sum-squared prediction error as the residual. The recursive orthogonal Least Squares algorithm (ROLS) is employed to train the model to overcome the training difficulty of the independent mode of the network. Then, another RBFNN is used as a fault classifier to isolate faults from different features involved in the residual vector. The several actuator and sensor faults are simulated in a nonlinear simulation of the reactor in Simulink. The scheme is used to detect and isolate the faults on-line. The simulation results show the effectiveness of the scheme even the process is subjected to disturbances and uncertainties including significant changes in the monomer feed rate, fouling factor, impurity factor, ambient temperature and measurement noise. The simulation results are presented to illustrate the effectiveness and robustness of the proposed method.Keywords: Robust fault detection, cascade control, independent RBF model, RBF neural networks, Chylla-Haase reactor, FDI under closed-loop control
Procedia PDF Downloads 497938 Quintic Spline Solution of Fourth-Order Parabolic Equations Arising in Beam Theory
Authors: Reza Mohammadi, Mahdieh Sahebi
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We develop a method based on polynomial quintic spline for numerical solution of fourth-order non-homogeneous parabolic partial differential equation with variable coefficient. By using polynomial quintic spline in off-step points in space and finite difference in time directions, we obtained two three level implicit methods. Stability analysis of the presented method has been carried out. We solve four test problems numerically to validate the derived method. Numerical comparison with other methods shows the superiority of presented scheme.Keywords: fourth-order parabolic equation, variable coefficient, polynomial quintic spline, off-step points
Procedia PDF Downloads 352937 A New Computational Method for the Solution of Nonlinear Burgers' Equation Arising in Longitudinal Dispersion Phenomena in Fluid Flow through Porous Media
Authors: Olayiwola Moruf Oyedunsi
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This paper discusses the Modified Variational Iteration Method (MVIM) for the solution of nonlinear Burgers’ equation arising in longitudinal dispersion phenomena in fluid flow through porous media. The method is an elegant combination of Taylor’s series and the variational iteration method (VIM). Using Maple 18 for implementation, it is observed that the procedure provides rapidly convergent approximation with less computational efforts. The result shows that the concentration C(x,t) of the contaminated water decreases as distance x increases for the given time t.Keywords: modified variational iteration method, Burger’s equation, porous media, partial differential equation
Procedia PDF Downloads 321936 The Planning Strategies of Public Sports Facilities Based on the Field Investigation: Case Study of Songyuan, China
Authors: Li Hua Li, Ling Ling Li
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With the National Fitness Program being established as a national strategy by the Chinese government, Chinese old planning strategies of sports facilities which are based on the purpose for hosting high-level sports events have been failed to meet the rapid growth of Chinese residents’ healthy needs. As the most important carrier for promoting the health of citizens in China, public sports facilities may have further conflicts when they are planned without considering the characteristics of the city itself and the fitness needs of the urban residents. With the planning practice in Songyuan in northeastern China, this paper explores the key planning strategies of public sports facilities through the field investigation to obtain the current situation of public sports facilities in Songyuan and the questionnaire to get the date of Songyuan residents’ fitness characteristics and needs. Findings from this investigation suggest that the planning of public sports facilities in Songyuan should first increase the quantities of public sports facilities at the community level, which could match the fitness population and meet the fitness needs in Songyuan. Secondly, the planning should combine with other available resources, such as urban parks, squares and other places where Songyuan residents often choose to do physical activities to enhance the vitality of public sports facilities. Finally, the planning should also link the urban transportation system in Songyuan to improve the accessibility and efficiency of public sports facilities. All these planning strategies could provide essential information for updating the urban and regional design of Songyuan.Keywords: field investigation, healthy needs, public sports facilities, planning strategies, questionnaire
Procedia PDF Downloads 237935 MHD Equilibrium Study in Alborz Tokamak
Authors: Maryamosadat Ghasemi, Reza Amrollahi
Abstract:
Plasma equilibrium geometry has a great influence on the confinement and magnetohydrodynamic stability in tokamaks. The poloidal field (PF) system of a tokamak should be able to support this plasma equilibrium geometry. In this work the prepared numerical code based on radial basis functions are presented and used to solve the Grad–Shafranov (GS) equation for the axisymmetric equilibrium of tokamak plasma. The radial basis functions (RBFs) which is a kind of numerical meshfree method (MFM) for solving partial differential equations (PDEs) has appeared in the last decade and is developing significantly in the last few years. This technique is applied in this study to obtain the equilibrium configuration for Alborz Tokamak. The behavior of numerical solution convergences show the validation of this calculations.Keywords: equilibrium, grad–shafranov, radial basis functions, Alborz Tokamak
Procedia PDF Downloads 473934 An Analytical Method for Bending Rectangular Plates with All Edges Clamped Supported
Authors: Yang Zhong, Heng Liu
Abstract:
The decoupling method and the modified Naiver method are combined for accurate bending analysis of rectangular thick plates with all edges clamped supported. The basic governing equations for Mindlin plates are first decoupled into independent partial differential equations which can be solved separately. Using modified Navier method, the analytic solution of rectangular thick plate with all edges clamped supported is then derived. The solution method used in this paper leave out the complicated derivation for calculating coefficients and obtain the solution to problems directly. Numerical comparisons show the correctness and accuracy of the results at last.Keywords: Mindlin plates, decoupling method, modified Navier method, bending rectangular plates
Procedia PDF Downloads 600