Search results for: non-functional parameters
6925 Numerical Solution of Manning's Equation in Rectangular Channels
Authors: Abdulrahman Abdulrahman
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When the Manning equation is used, a unique value of normal depth in the uniform flow exists for a given channel geometry, discharge, roughness, and slope. Depending on the value of normal depth relative to the critical depth, the flow type (supercritical or subcritical) for a given characteristic of channel conditions is determined whether or not flow is uniform. There is no general solution of Manning's equation for determining the flow depth for a given flow rate, because the area of cross section and the hydraulic radius produce a complicated function of depth. The familiar solution of normal depth for a rectangular channel involves 1) a trial-and-error solution; 2) constructing a non-dimensional graph; 3) preparing tables involving non-dimensional parameters. Author in this paper has derived semi-analytical solution to Manning's equation for determining the flow depth given the flow rate in rectangular open channel. The solution was derived by expressing Manning's equation in non-dimensional form, then expanding this form using Maclaurin's series. In order to simplify the solution, terms containing power up to 4 have been considered. The resulted equation is a quartic equation with a standard form, where its solution was obtained by resolving this into two quadratic factors. The proposed solution for Manning's equation is valid over a large range of parameters, and its maximum error is within -1.586%.Keywords: channel design, civil engineering, hydraulic engineering, open channel flow, Manning's equation, normal depth, uniform flow
Procedia PDF Downloads 2086924 On the Role of Cutting Conditions on Surface Roughness in High-Speed Thread Milling of Brass C3600
Authors: Amir Mahyar Khorasani, Ian Gibson, Moshe Goldberg, Mohammad Masoud Movahedi, Guy Littlefair
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One of the important factors in manufacturing processes especially machining operations is surface quality. Improving this parameter results in improving fatigue strength, corrosion resistance, creep life and surface friction. The reliability and clearance of removable joints such as thread and nuts are highly related to the surface roughness. In this work, the effect of different cutting parameters such as cutting fluid pressure, feed rate and cutting speed on the surface quality of the crest of thread in the high-speed milling of Brass C3600 have been determined. Two popular neural networks containing MLP and RBF coupling with Taguchi L32 have been used to model surface roughness which was shown to be highly adept for such tasks. The contribution of this work is modelling surface roughness on the crest of the thread by using precise profilometer with nanoscale resolution. Experimental tests have been carried out for validation and approved suitable accuracy of the proposed model. Also analysing the interaction of parameters two by two showed that the most effective cutting parameter on the surface value is feed rate followed by cutting speed and cutting fluid pressure.Keywords: artificial neural networks, cutting conditions, high-speed machining, surface roughness, thread milling
Procedia PDF Downloads 3686923 Effect of Humic Substance on Ex-Vitro Propagation of Saffron (Crocus Sativus L.)
Authors: Abdelghani Tahiri, Youssef Karra, Naima Ait Aabd, Abdelaziz Mimouni
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Saffron (Crocus sativus L.), the most expensive spice in the world derived from the stigmas, is an autumn-flowering and sterile triploid (2n=3x=24) geophyte species that belong to the Iridaceae family. This plant species is mainly propagated vegetatively through the formation of daughter corms from the mother one. Low multiplication rates of daughter corms under natural conditions, along with fungal contamination, significantly reduce the productivity and quality of saffron corms. The development of efficient and sustainable strategies for rapid and large-scale production of selected cultivars of saffron will be desired. For this, the main objective of this work is to improve the vegetative propagation of saffron under ex-vitro conditions. Preliminary results of the influence of increasing doses of humic substances (HS) on the growth and multiplication of corms under greenhouse conditions are evaluated. The obtained data shows that the effect of HS depends on the concentration used and the mode of application. Indeed, the application through irrigation has increased the number of shoots and corms, but it has reduced other parameters. On the other hand, the temporary treatment has improved all observed parameters except for the number of shoots and corms. Results obtained in this work suggest that it is possible to improve the propagation of saffron corms under greenhouse conditions.Keywords: saffron, Crocus sativus L., corm, humic substances
Procedia PDF Downloads 2046922 Investigation of the Mechanical and Thermal Properties of a Silver Oxalate Nanoporous Structured Sintered Joint for Micro-joining in Relation to the Sintering Process Parameters
Authors: L. Vivet, L. Benabou, O. Simon
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With highly demanding applications in the field of power electronics, there is an increasing need to have interconnection materials with properties that can ensure both good mechanical assembly and high thermal/electrical conductivities. So far, lead-free solders have been considered an attractive solution, but recently, sintered joints based on nano-silver paste have been used for die attach and have proved to be a promising solution offering increased performances in high-temperature applications. In this work, the main parameters of the bonding process using silver oxalates are studied, i.e., the heating rate and the bonding pressure mainly. Their effects on both the mechanical and thermal properties of the sintered layer are evaluated following an experimental design. Pairs of copper substrates with gold metallization are assembled through the sintering process to realize the samples that are tested using a micro-traction machine. In addition, the obtained joints are examined through microscopy to identify the important microstructural features in relation to the measured properties. The formation of an intermetallic compound at the junction between the sintered silver layer and the gold metallization deposited on copper is also analyzed. Microscopy analysis exhibits a nanoporous structure of the sintered material. It is found that higher temperature and bonding pressure result in higher densification of the sintered material, with higher thermal conductivity of the joint but less mechanical flexibility to accommodate the thermo-mechanical stresses arising during service. The experimental design allows hence the determination of the optimal process parameters to reach sufficient thermal/mechanical properties for a given application. It is also found that the interphase formed between silver and gold metallization is the location where the fracture occurred after the mechanical testing, suggesting that the inter-diffusion mechanism between the different elements of the assembly leads to the formation of a relatively brittle compound.Keywords: nanoporous structure, silver oxalate, sintering, mechanical strength, thermal conductivity, microelectronic packaging
Procedia PDF Downloads 886921 Treatment of Municipal Wastewater by Means of Uv-Assisted Irradiation Technologies: Fouling Studies and Optimization of Operational Parameters
Authors: Tooba Aslam, Efthalia Chatzisymeon
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UV-assisted irradiation technologies are well-established for water and wastewater treatment. UVC treatments are widely used at large-scale, while UVA irradiation has more often been applied in combination with a catalyst (e.g. TiO₂ or FeSO₄) in smaller-scale systems. A technical issue of these systems is the formation of fouling on the quartz sleeves that houses the lamps. This fouling can prevent complete irradiation, therefore reducing the efficiency of the process. This paper investigates the effects of operational parameters, such as the type of wastewater, irradiation source, H₂O₂ addition, and water pH on fouling formation and, ultimately, the treatment of municipal wastewater. Batch experiments have been performed at lab-scale while monitoring water quality parameters including: COD, TS, TSS, TDS, temperature, pH, hardness, alkalinity, turbidity, TOC, UV transmission, UV₂₅₄ absorbance, and metal concentrations. The residence time of the wastewater in the reactor was 5 days in order to observe any fouling formation on the quartz surface. Over this period, it was observed that chemical oxygen demand (COD) decreased by 30% and 59% during photolysis (Ultraviolet A) and photo-catalysis (UVA/Fe/H₂O₂), respectively. Higher fouling formation was observed with iron-rich and phosphorous-rich wastewater. The highest rate of fouling was developed with phosphorous-rich wastewater, followed by the iron-rich wastewater. Photo-catalysis (UVA/Fe/H₂O₂) had better removal efficiency than photolysis (UVA). This was attributed to the Photo-Fenton reaction, which was initiated under these operational conditions. Scanning electron microscope (SEM) measurements of fouling formed on the quartz sleeves showed that particles vary in size, shape, and structure; some have more distinct structures and are generally larger and have less compact structure than the others. Energy-dispersive X-ray spectroscopy (EDX) results showed that the major metals present in the fouling cake were iron, phosphorous, and calcium. In conclusion, iron-rich wastewaters are more suitable for UV-assisted treatment since fouling formation on quartz sleeves can be minimized by the formation of oxidizing agents during treatment, such as hydroxyl radicals.Keywords: advanced oxidation processes, photo-fenton treatment, photo-catalysis, wastewater treatment
Procedia PDF Downloads 706920 Design and Optimization for a Compliant Gripper with Force Regulation Mechanism
Authors: Nhat Linh Ho, Thanh-Phong Dao, Shyh-Chour Huang, Hieu Giang Le
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This paper presents a design and optimization for a compliant gripper. The gripper is constructed based on the concept of compliant mechanism with flexure hinge. A passive force regulation mechanism is presented to control the grasping force a micro-sized object instead of using a sensor force. The force regulation mechanism is designed using the planar springs. The gripper is expected to obtain a large range of displacement to handle various sized objects. First of all, the statics and dynamics of the gripper are investigated by using the finite element analysis in ANSYS software. And then, the design parameters of the gripper are optimized via Taguchi method. An orthogonal array L9 is used to establish an experimental matrix. Subsequently, the signal to noise ratio is analyzed to find the optimal solution. Finally, the response surface methodology is employed to model the relationship between the design parameters and the output displacement of the gripper. The design of experiment method is then used to analyze the sensitivity so as to determine the effect of each parameter on the displacement. The results showed that the compliant gripper can move with a large displacement of 213.51 mm and the force regulation mechanism is expected to be used for high precision positioning systems.Keywords: flexure hinge, compliant mechanism, compliant gripper, force regulation mechanism, Taguchi method, response surface methodology, design of experiment
Procedia PDF Downloads 3186919 Reliability of Using Standard Penetration Test (SPT) in Evaluation of Soil Properties
Authors: Hossein Alimohammadi, Mohsen Amirmojahedi, Mehrdad Rowhani
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Soil properties are used by geotechnical engineers to evaluate and analyze site conditions for designing purposes. Although basic soil classification tests are easy to perform and provide useful information to determine the properties of soils, it may take time to get the result and add some costs to the projects. Standard Penetration Test (SPT) provides an opportunity to evaluate soil parameters without performing laboratory tests. In addition to its simplicity and cheapness, the results become available immediately. This research provides a guideline on the application of the SPT test method, reliability of adapting the SPT test results in evaluating soil physical and mechanical properties such as Atterberg limits, shear strength, and compressive strength compressibility parameters. A total of 70 boreholes were investigated in this study by taking soil samples between depths of 1.2 to 15.25 meters. The project site was located in Morrow County, Ohio. A regression-based formula was proposed based on Tobit regression with a stepwise variable selection analysis conducted between SPT and other typical soil properties obtained from soil tests. The results of the research illustrated that the shear strength and physical properties of the soil affect the SPT number. The proposed correlation can help engineers to use SPT test results in their design with higher accuracy.Keywords: standard penetration test, soil properties, soil classification, regression method
Procedia PDF Downloads 1776918 Research on the Two-Way Sound Absorption Performance of Multilayer Material
Authors: Yang Song, Xiaojun Qiu
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Multilayer materials are applied to much acoustics area. Multilayer porous materials are dominant in room absorber. Multilayer viscoelastic materials are the basic parts in underwater absorption coating. In most cases, the one-way sound absorption performance of multilayer material is concentrated according to the sound source site. But the two-way sound absorption performance is also necessary to be known in some special cases which sound is produced in both sides of the material and the both sides especially might contact with different media. In this article, this kind of case was research. The multilayer material was composed of viscoelastic layer and steel plate and the porous layer. The two sides of multilayer material contact with water and air, respectively. A theory model was given to describe the sound propagation and impedance in multilayer absorption material. The two-way sound absorption properties of several multilayer materials were calculated whose two sides all contacted with different media. The calculated results showed that the difference of two-way sound absorption coefficients is obvious. The frequency, the relation of layers thickness and parameters of multilayer materials all have an influence on the two-way sound absorption coefficients. But the degrees of influence are varied. All these simulation results were analyzed in the article. It was obtained that two-way sound absorption at different frequencies can be promoted by optimizing the configuration parameters. This work will improve the performance of underwater sound absorption coating which can absorb incident sound from the water and reduce the noise radiation from inside space.Keywords: different media, multilayer material, sound absorption coating, two-way sound absorption
Procedia PDF Downloads 5306917 Deep Reinforcement Learning Model Using Parameterised Quantum Circuits
Authors: Lokes Parvatha Kumaran S., Sakthi Jay Mahenthar C., Sathyaprakash P., Jayakumar V., Shobanadevi A.
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With the evolution of technology, the need to solve complex computational problems like machine learning and deep learning has shot up. But even the most powerful classical supercomputers find it difficult to execute these tasks. With the recent development of quantum computing, researchers and tech-giants strive for new quantum circuits for machine learning tasks, as present works on Quantum Machine Learning (QML) ensure less memory consumption and reduced model parameters. But it is strenuous to simulate classical deep learning models on existing quantum computing platforms due to the inflexibility of deep quantum circuits. As a consequence, it is essential to design viable quantum algorithms for QML for noisy intermediate-scale quantum (NISQ) devices. The proposed work aims to explore Variational Quantum Circuits (VQC) for Deep Reinforcement Learning by remodeling the experience replay and target network into a representation of VQC. In addition, to reduce the number of model parameters, quantum information encoding schemes are used to achieve better results than the classical neural networks. VQCs are employed to approximate the deep Q-value function for decision-making and policy-selection reinforcement learning with experience replay and the target network.Keywords: quantum computing, quantum machine learning, variational quantum circuit, deep reinforcement learning, quantum information encoding scheme
Procedia PDF Downloads 1186916 Effect of Infill’s in Influencing the Dynamic Responses of Multistoried Structures
Authors: Rahmathulla Noufal E.
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Investigating the dynamic responses of high rise structures under the effect of siesmic ground motion is extremely important for the proper analysis and design of multitoried structures. Since the presence of infilled walls strongly influences the behaviour of frame systems in multistoried buildings, there is an increased need for developing guidelines for the analysis and design of infilled frames under the effect of dynamic loads for safe and proper design of buildings. In this manuscript, we evaluate the natural frequencies and natural periods of single bay single storey frames considering the effect of infill walls by using the Eigen value analysis and validating with SAP 2000 (free vibration analysis). Various parameters obtained from the diagonal strut model followed for the free vibration analysis is then compared with the Finite Element model, where infill is modeled as shell elements (four noded). We also evaluated the effect of various parameters on the natural periods of vibration obtained by free vibration analysis in SAP 2000 comparing them with those obtained by the empirical expressions presented in I.S. 1893(Part I)-2002.Keywords: infilled frame, eigen value analysis, free vibration analysis, diagonal strut model, finite element model, SAP 2000, natural period
Procedia PDF Downloads 3166915 Detecting Venomous Files in IDS Using an Approach Based on Data Mining Algorithm
Authors: Sukhleen Kaur
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In security groundwork, Intrusion Detection System (IDS) has become an important component. The IDS has received increasing attention in recent years. IDS is one of the effective way to detect different kinds of attacks and malicious codes in a network and help us to secure the network. Data mining techniques can be implemented to IDS, which analyses the large amount of data and gives better results. Data mining can contribute to improving intrusion detection by adding a level of focus to anomaly detection. So far the study has been carried out on finding the attacks but this paper detects the malicious files. Some intruders do not attack directly, but they hide some harmful code inside the files or may corrupt those file and attack the system. These files are detected according to some defined parameters which will form two lists of files as normal files and harmful files. After that data mining will be performed. In this paper a hybrid classifier has been used via Naive Bayes and Ripper classification methods. The results show how the uploaded file in the database will be tested against the parameters and then it is characterised as either normal or harmful file and after that the mining is performed. Moreover, when a user tries to mine on harmful file it will generate an exception that mining cannot be made on corrupted or harmful files.Keywords: data mining, association, classification, clustering, decision tree, intrusion detection system, misuse detection, anomaly detection, naive Bayes, ripper
Procedia PDF Downloads 4086914 Chebyshev Collocation Method for Solving Heat Transfer Analysis for Squeezing Flow of Nanofluid in Parallel Disks
Authors: Mustapha Rilwan Adewale, Salau Ayobami Muhammed
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This study focuses on the heat transfer analysis of magneto-hydrodynamics (MHD) squeezing flow between parallel disks, considering a viscous incompressible fluid. The upper disk exhibits both upward and downward motion, while the lower disk remains stationary but permeable. By employing similarity transformations, a system of nonlinear ordinary differential equations is derived to describe the flow behavior. To solve this system, a numerical approach, namely the Chebyshev collocation method, is utilized. The study investigates the influence of flow parameters and compares the obtained results with existing literature. The significance of this research lies in understanding the heat transfer characteristics of MHD squeezing flow, which has practical implications in various engineering and industrial applications. By employing the similarity transformations, the complex governing equations are simplified into a system of nonlinear ordinary differential equations, facilitating the analysis of the flow behavior. To obtain numerical solutions for the system, the Chebyshev collocation method is implemented. This approach provides accurate approximations for the nonlinear equations, enabling efficient computations of the heat transfer properties. The obtained results are compared with existing literature, establishing the validity and consistency of the numerical approach. The study's major findings shed light on the influence of flow parameters on the heat transfer characteristics of the squeezing flow. The analysis reveals the impact of parameters such as magnetic field strength, disk motion amplitude, fluid viscosity on the heat transfer rate between the disks, the squeeze number(S), suction/injection parameter(A), Hartman number(M), Prandtl number(Pr), modified Eckert number(Ec), and the dimensionless length(δ). These findings contribute to a comprehensive understanding of the system's behavior and provide insights for optimizing heat transfer processes in similar configurations. In conclusion, this study presents a thorough heat transfer analysis of magneto-hydrodynamics squeezing flow between parallel disks. The numerical solutions obtained through the Chebyshev collocation method demonstrate the feasibility and accuracy of the approach. The investigation of flow parameters highlights their influence on heat transfer, contributing to the existing knowledge in this field. The agreement of the results with previous literature further strengthens the reliability of the findings. These outcomes have practical implications for engineering applications and pave the way for further research in related areas.Keywords: squeezing flow, magneto-hydro-dynamics (MHD), chebyshev collocation method(CCA), parallel manifolds, finite difference method (FDM)
Procedia PDF Downloads 636913 Comparison between the Quadratic and the Cubic Linked Interpolation on the Mindlin Plate Four-Node Quadrilateral Finite Elements
Authors: Dragan Ribarić
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We employ the so-called problem-dependent linked interpolation concept to develop two cubic 4-node quadrilateral Mindlin plate finite elements with 12 external degrees of freedom. In the problem-independent linked interpolation, the interpolation functions are independent of any problem material parameters and the rotation fields are not expressed in terms of the nodal displacement parameters. On the contrary, in the problem-dependent linked interpolation, the interpolation functions depend on the material parameters and the rotation fields are expressed in terms of the nodal displacement parameters. Two cubic 4-node quadrilateral plate elements are presented, named Q4-U3 and Q4-U3R5. The first one is modelled with one displacement and two rotation degrees of freedom in every of the four element nodes and the second element has five additional internal degrees of freedom to get polynomial completeness of the cubic form and which can be statically condensed within the element. Both elements are able to pass the constant-bending patch test exactly as well as the non-zero constant-shear patch test on the oriented regular mesh geometry in the case of cylindrical bending. In any mesh shape, the elements have the correct rank and only the three eigenvalues, corresponding to the solid body motions are zero. There are no additional spurious zero modes responsible for instability of the finite element models. In comparison with the problem-independent cubic linked interpolation implemented in Q9-U3, the nine-node plate element, significantly less degrees of freedom are employed in the model while retaining the interpolation conformity between adjacent elements. The presented elements are also compared to the existing problem-independent quadratic linked-interpolation element Q4-U2 and to the other known elements that also use the quadratic or the cubic linked interpolation, by testing them on several benchmark examples. Simple functional upgrading from the quadratic to the cubic linked interpolation, implemented in Q4-U3 element, showed no significant improvement compared to the quadratic linked form of the Q4-U2 element. Only when the additional bubble terms are incorporated in the displacement and rotation function fields, which complete the full cubic linked interpolation form, qualitative improvement is fulfilled in the Q4-U3R5 element. Nevertheless, the locking problem exists even for the both presented elements, like in all pure displacement elements when applied to very thin plates modelled by coarse meshes. But good and even slightly better performance can be noticed for the Q4-U3R5 element when compared with elements from the literature, if the model meshes are moderately dense and the plate thickness not extremely thin. In some cases, it is comparable to or even better than Q9-U3 element which has as many as 12 more external degrees of freedom. A significant improvement can be noticed in particular when modeling very skew plates and models with singularities in the stress fields as well as circular plates with distorted meshes.Keywords: Mindlin plate theory, problem-independent linked interpolation, problem-dependent interpolation, quadrilateral displacement-based plate finite elements
Procedia PDF Downloads 3056912 Effect of Different Processing Methods on the Proximate, Functional, Sensory, and Nutritional Properties of Weaning Foods Formulated from Maize (Zea mays) and Soybean (Glycine max) Flour Blends
Authors: C. O. Agu, C. C. Okafor
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Maize and soybean flours were produced using different methods of processing which include fermentation (FWF), roasting (RWF) and malting (MWF). Products from the different methods were mixed in the ratio 60:40 maize/soybean, respectively. These composites mixed with other ingredients such as sugar, vegetable oil, vanilla flavour and vitamin mix were analyzed for proximate composition, physical/functional, sensory and nutritional properties. The results for the protein content ranged between 6.25% and 16.65% with sample RWF having the highest value. Crude fibre values ranged from 3.72 to 10.0%, carbohydrate from 58.98% to 64.2%, ash from 1.27 to 2.45%. Physical and functional properties such as bulk density, wettability, gelation capacity have values between 0.74 and 0.76g/ml, 20.33 and 46.33 min and 0.73 to 0.93g/ml, respectively. On the sensory quality colour, flavour, taste, texture and general acceptability were determined. In terms of colour and flavour there was no significant difference (P < 0.05) while the values for taste ranged between 4.89 and 7.1 l, texture 5.50 to 8.38 and general acceptability 6.09 and 7.89. Nutritionally there is no significant difference (P < 0.05) between sample RWF and the control in all parameters considered. Samples FWF and MWF showed significantly (P < 0.5) lower values in all parameters determined. In the light of the above findings, roasting method is highly recommend in the production of weaning foods.Keywords: fermentation, malting, ratio, roasting, wettability
Procedia PDF Downloads 2956911 Modeling of Anisotropic Hardening Based on Crystal Plasticity Theory and Virtual Experiments
Authors: Bekim Berisha, Sebastian Hirsiger, Pavel Hora
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Advanced material models involving several sets of model parameters require a big experimental effort. As models are getting more and more complex like e.g. the so called “Homogeneous Anisotropic Hardening - HAH” model for description of the yielding behavior in the 2D/3D stress space, the number and complexity of the required experiments are also increasing continuously. In the context of sheet metal forming, these requirements are even more pronounced, because of the anisotropic behavior or sheet materials. In addition, some of the experiments are very difficult to perform e.g. the plane stress biaxial compression test. Accordingly, tensile tests in at least three directions, biaxial tests and tension-compression or shear-reverse shear experiments are performed to determine the parameters of the macroscopic models. Therefore, determination of the macroscopic model parameters based on virtual experiments is a very promising strategy to overcome these difficulties. For this purpose, in the framework of multiscale material modeling, a dislocation density based crystal plasticity model in combination with a FFT-based spectral solver is applied to perform virtual experiments. Modeling of the plastic behavior of metals based on crystal plasticity theory is a well-established methodology. However, in general, the computation time is very high and therefore, the computations are restricted to simplified microstructures as well as simple polycrystal models. In this study, a dislocation density based crystal plasticity model – including an implementation of the backstress – is used in a spectral solver framework to generate virtual experiments for three deep drawing materials, DC05-steel, AA6111-T4 and AA4045 aluminum alloys. For this purpose, uniaxial as well as multiaxial loading cases, including various pre-strain histories, has been computed and validated with real experiments. These investigations showed that crystal plasticity modeling in the framework of Representative Volume Elements (RVEs) can be used to replace most of the expensive real experiments. Further, model parameters of advanced macroscopic models like the HAH model can be determined from virtual experiments, even for multiaxial deformation histories. It was also found that crystal plasticity modeling can be used to model anisotropic hardening more accurately by considering the backstress, similar to well-established macroscopic kinematic hardening models. It can be concluded that an efficient coupling of crystal plasticity models and the spectral solver leads to a significant reduction of the amount of real experiments needed to calibrate macroscopic models. This advantage leads also to a significant reduction of computational effort needed for the optimization of metal forming process. Further, due to the time efficient spectral solver used in the computation of the RVE models, detailed modeling of the microstructure are possible.Keywords: anisotropic hardening, crystal plasticity, micro structure, spectral solver
Procedia PDF Downloads 3066910 Response of Onion to FTM and Inorganic Fertilizers Application on Growth, Yield and Nutrient Uptake in Lateritic Soil of Konkan
Authors: Rupali Thorat, S. B. Dodake, V. N. Palsande, S. D. Patil
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A field experiment was conducted to study the “Response of onion to FYM and inorganic fertilizers application on growth, yield and nutrient uptake in lateritic soil of Konkan” at the farm of Pangari block of Irrigation of Scheme, Central Experimentation Station, Wakawali during Rabi 2009-10. There were 12 treatment combinations, comprising of 3 levels of NPK fertilizers (C1 ,C2-125 kg N, 62.5 kg P205 and 62.5 kg K20 ha-1 and C3-150 kg N, 75 kg P205 and 75 kg K20 ha-1) and 4 levels of FYM (F1-10 t FYM ha-1, F2 - 15 t FYM ha-1, F3-20 t FYM ha-1, F4-25 t FYM ha-1) replicated thrice using Factorial Randomized Block Design. The observations on plant height, number of leaves, girth of plant, polar and equatorial diameter of bulb as well as dry matter yield, onion bulb yield recorded during the course of field study were subjected to statistical analysis. Similarly nutrient content and uptake, quality parameters of bulb and soil properties were also determined and their data were also analyzed statistically. It is revealed from the study that the growth attributes, dry matter yield, onion bulb yield, nutrient content, nutrient uptake, quality parameters were improved significantly due to application of NPK @ 150:75:75 kg ha-1 along with FYM @ 20 t ha-1(C3F3). Application of NPK @ 150:75:75 kg ha-1 along with FYM @ 20 t ha-1 (C3F3) registered highest onion bulb yield (t ha-1). The quality of onion as well as availability of N, P, K, Fe, Mn, Zn and Cu in the soil was improved due to application of NPK @ 150:75:75 kg ha-1 and FYM @ 20 t ha-1.Keywords: onion, FYM, yield, nutrient uptake and fertilizer
Procedia PDF Downloads 4776909 Multivariate Analytical Insights into Spatial and Temporal Variation in Water Quality of a Major Drinking Water Reservoir
Authors: Azadeh Golshan, Craig Evans, Phillip Geary, Abigail Morrow, Zoe Rogers, Marcel Maeder
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22 physicochemical variables have been determined in water samples collected weekly from January to December in 2013 from three sampling stations located within a major drinking water reservoir. Classical Multivariate Curve Resolution Alternating Least Squares (MCR-ALS) analysis was used to investigate the environmental factors associated with the physico-chemical variability of the water samples at each of the sampling stations. Matrix augmentation MCR-ALS (MA-MCR-ALS) was also applied, and the two sets of results were compared for interpretative clarity. Links between these factors, reservoir inflows and catchment land-uses were investigated and interpreted in relation to chemical composition of the water and their resolved geographical distribution profiles. The results suggested that the major factors affecting reservoir water quality were those associated with agricultural runoff, with evidence of influence on algal photosynthesis within the water column. Water quality variability within the reservoir was also found to be strongly linked to physical parameters such as water temperature and the occurrence of thermal stratification. The two methods applied (MCR-ALS and MA-MCR-ALS) led to similar conclusions; however, MA-MCR-ALS appeared to provide results more amenable to interpretation of temporal and geological variation than those obtained through classical MCR-ALS.Keywords: drinking water reservoir, multivariate analysis, physico-chemical parameters, water quality
Procedia PDF Downloads 2836908 Theoretical Study of Structural and Electronic Properties of Matlockite CaFX (X = I and Br) Compounds
Authors: Meriem Harmel, Houari Khachai
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The full potential linearized augmented plane wave (FP-LAPW)method within density functional theory is applied to study, for the first time, the structural and electronic properties of CaFI and to compare them with CaFCl and CaFBr, all compounds belonging to the tetragonal PbFCl structure group with space group P4/nmm. We used the generalized gradient approximation (GGA) based on exchange–correlation energy optimization to calculate the total energy and also the Engel– Vosko GGA formalism, which optimizes the corresponding potential for band structure calculations. Ground state properties such as the lattice parameters, c/a ratio, bulk modulus, pressure derivative of the bulk modulus and cohesive energy are calculated, as well as the optimized internal parameters, by relaxing the atomic position in the force directions. The variations of the calculated interatomic distances and angles between different atomic bonds are discussed. CaFCl was found to have a direct band gap at whereas CaFBr and BaFI have indirect band gaps. From these computed bands, all three materials are found to be insulators having band gaps of 6.28, 5.46, and 4.50 eV, respectively. We also calculated the valence charge density and the total density of states at equilibrium volume for each compound. The results are in reasonable agreement with the available experimental data.Keywords: DFT, matlockite, structural properties, electronic structure
Procedia PDF Downloads 3096907 Passivization: as Syntactic Argument Decreasing Parameter in Boro
Authors: Ganga Brahma
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Boro employs verbs hooked up with morphemes which lead verbs to adjust with their arguments and hence, affecting the whole of sentence structures. This paper is based on few such syntactic parameters which are usually considered as argument decreasing parameters in linguistic works. Passivizing of few transitive clauses which are usually construed from the verbs occurring with certain morphemes and representation in middle constructions are few of such strategies which lead to conceptualizing of decreasing of syntactic arguments from a sentence. This paper focuses on the mentioned linguistic strategies and attempts to describe the linguistic processes as for how these parameters work in languages especially by concentrating on a particular Tibeto-Burman language i.e. Boro. Boro is a Tibeto-Burman language widely spoken in parts of the north-eastern regions of India. It has an agglutinative nature in forming words as well as clauses. There is a morpheme ‘za’ which means ‘to happen, become’ in Boro whose appearances with verb roots denotes an idea of the subject being passivized. Passivization, usually has notions that it is a reversed representation of its active sentence forms in the terms of argument placements. (However, it is not accountably true as passives and actives have some distinct features of their own and independent of one and the other.) This particular work will concentrate on the semantics of passivization at the same time along with its syntactic reality. The verb khɑo meaning ‘to steal’ offers a sense of passivization with the appearance of the morpheme zɑ which means ‘to happen, become’ (e.g Zunu-ɑ lama-ɑo phɯisɑ khɑo-zɑ-bɑi; Junu-NOM road-LOC money steal-PASS-PRES: Junu got her money stolen on the road). The focus, here, is more on the argument placed at the subject position (i.e. Zunu) and the event taken place. The semantics of such construction asks for the agent because without an agent the event could not have taken place. However, the syntactic elements fill the slots of relegated or temporarily deleted agent which, infact, is the actual subject cum agent in its active representation. Due to the event marker ‘zɑ’ in this presentation it affords to reduce one participant from such a situation which in actual is made up of three participants. Hence, the structure of di-transitive construction here reduces to mono-transitive structure. Unlike passivization, middle construction does not allow relegation of the agents. It permanently deletes agents. However, it also focuses on the fore-grounded subject and highlighting on the changed states on the subjects which happens to be the underlying objects of their respective transitive structures (with agents). This work intends to describe how these two parameters which are different at their semantic realization can meet together at a syntactic level in order to create a linguistic parameter that decreases participants from their actual structures which are with more than one participant.Keywords: argument-decrease, middle-construction, passivization, transitivity-intransitivity
Procedia PDF Downloads 2276906 Stabilization Control of the Nonlinear AIDS Model Based on the Theory of Polynomial Fuzzy Control Systems
Authors: Shahrokh Barati
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In this paper, we introduced AIDS disease at first, then proposed dynamic model illustrate its progress, after expression of a short history of nonlinear modeling by polynomial phasing systems, we considered the stability conditions of the systems, which contained a huge amount of researches in order to modeling and control of AIDS in dynamic nonlinear form, in this approach using a frame work of control any polynomial phasing modeling system which have been generalized by part of phasing model of T-S, in order to control the system in better way, the stability conditions were achieved based on polynomial functions, then we focused to design the appropriate controller, firstly we considered the equilibrium points of system and their conditions and in order to examine changes in the parameters, we presented polynomial phase model that was the generalized approach rather than previous Takagi Sugeno models, then with using case we evaluated the equations in both open loop and close loop and with helping the controlling feedback, the close loop equations of system were calculated, to simulate nonlinear model of AIDS disease, we used polynomial phasing controller output that was capable to make the parameters of a nonlinear system to follow a sustainable reference model properly.Keywords: polynomial fuzzy, AIDS, nonlinear AIDS model, fuzzy control systems
Procedia PDF Downloads 4576905 Development of Fuzzy Logic and Neuro-Fuzzy Surface Roughness Prediction Systems Coupled with Cutting Current in Milling Operation
Authors: Joseph C. Chen, Venkata Mohan Kudapa
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Development of two real-time surface roughness (Ra) prediction systems for milling operations was attempted. The systems used not only cutting parameters, such as feed rate and spindle speed, but also the cutting current generated and corrected by a clamp type energy sensor. Two different approaches were developed. First, a fuzzy inference system (FIS), in which the fuzzy logic rules are generated by experts in the milling processes, was used to conduct prediction modeling using current cutting data. Second, a neuro-fuzzy system (ANFIS) was explored. Neuro-fuzzy systems are adaptive techniques in which data are collected on the network, processed, and rules are generated by the system. The inference system then uses these rules to predict Ra as the output. Experimental results showed that the parameters of spindle speed, feed rate, depth of cut, and input current variation could predict Ra. These two systems enable the prediction of Ra during the milling operation with an average of 91.83% and 94.48% accuracy by FIS and ANFIS systems, respectively. Statistically, the ANFIS system provided better prediction accuracy than that of the FIS system.Keywords: surface roughness, input current, fuzzy logic, neuro-fuzzy, milling operations
Procedia PDF Downloads 1316904 Neural Network Modelling for Turkey Railway Load Carrying Demand
Authors: Humeyra Bolakar Tosun
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The transport sector has an undisputed place in human life. People need transport access to continuous increase day by day with growing population. The number of rail network, urban transport planning, infrastructure improvements, transportation management and other related areas is a key factor affecting our country made it quite necessary to improve the work of transportation. In this context, it plays an important role in domestic rail freight demand planning. Alternatives that the increase in the transportation field and has made it mandatory requirements such as the demand for improving transport quality. In this study generally is known and used in studies by the definition, rail freight transport, railway line length, population, energy consumption. In this study, Iron Road Load Net Demand was modeled by multiple regression and ANN methods. In this study, model dependent variable (Output) is Iron Road Load Net demand and 6 entries variable was determined. These outcome values extracted from the model using ANN and regression model results. In the regression model, some parameters are considered as determinative parameters, and the coefficients of the determinants give meaningful results. As a result, ANN model has been shown to be more successful than traditional regression model.Keywords: railway load carrying, neural network, modelling transport, transportation
Procedia PDF Downloads 1366903 Geochemical and Spatial Distribution of Minerals in the Tailings of IFE/IJESA Gold Mine Zone, Nigeria
Authors: Oladejo S. O, Tomori W. B, Adebayo A. O
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The main objective of this research is to identify the geochemical and mineralogical characteristics potential of unexplored tailings around the gold deposit region using spatial statistics and map modeling. Some physicochemical parameters such as pH, redox potential, electrical conductivity, cation exchange capacity, total organic carbon, total organic matter, residual humidity, Cation exchange capacity, and particle size were determined from both the mine drains and tailing samples using standard methods. The physicochemical parameters of tailings ranges obtained were pH (6.0 – 7.3), Eh (−16 - 95 Mev), EC (49 - 156 µS/cm), RH (0.20-2.60%), CEC (3.64-6.45 cmol/kg), TOC (3.57-18.62%), TOM (6.15-22.93%). The geochemical oxide composition were identified using Proton Induced X-ray emission and the results indicated that SiO2>Al2O3>Fe2O3>TiO2>K2O>MgO>CaO>Na2O> P2O5>MnO>Cr2O3>SrO>K2O>P2O5. The major mineralogical components in the tailing samples were determined by quantitative X-ray diffraction techniques using the Rietveld method. Geostatistical relationships among the known points were determined using ArcGIS 10.2 software to interpolate mineral concentration with respect to the study area. The Rietveld method gave a general Quartz value of 73.73-92.76%, IImenite as 0.38-4.77%, Kaolinite group as 3.19-20.83%, Muscovite as 0.77-11.70% with a trace of other minerals. The high percentage of quartz is an indication of a sandy environment with a loose binding site.Keywords: tailings, geochemical, mineralogy, spatial
Procedia PDF Downloads 556902 Emerging Research Trends in Routing Protocol for Wireless Sensor Network
Authors: Subhra Prosun Paul, Shruti Aggarwal
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Now a days Routing Protocol in Wireless Sensor Network has become a promising technique in the different fields of the latest computer technology. Routing in Wireless Sensor Network is a demanding task due to the different design issues of all sensor nodes. Network architecture, no of nodes, traffic of routing, the capacity of each sensor node, network consistency, service value are the important factor for the design and analysis of Routing Protocol in Wireless Sensor Network. Additionally, internal energy, the distance between nodes, the load of sensor nodes play a significant role in the efficient routing protocol. In this paper, our intention is to analyze the research trends in different routing protocols of Wireless Sensor Network in terms of different parameters. In order to explain the research trends on Routing Protocol in Wireless Sensor Network, different data related to this research topic are analyzed with the help of Web of Science and Scopus databases. The data analysis is performed from global perspective-taking different parameters like author, source, document, country, organization, keyword, year, and a number of the publication. Different types of experiments are also performed, which help us to evaluate the recent research tendency in the Routing Protocol of Wireless Sensor Network. In order to do this, we have used Web of Science and Scopus databases separately for data analysis. We have observed that there has been a tremendous development of research on this topic in the last few years as it has become a very popular topic day by day.Keywords: analysis, routing protocol, research trends, wireless sensor network
Procedia PDF Downloads 2066901 Assessment of Surface Water Quality near Landfill Sites Using a Water Pollution Index
Authors: Alejandro Cittadino, David Allende
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Landfilling of municipal solid waste is a common waste management practice in Argentina as in many parts of the world. There is extensive scientific literature on the potential negative effects of landfill leachates on the environment, so it’s necessary to be rigorous with the control and monitoring systems. Due to the specific municipal solid waste composition in Argentina, local landfill leachates contain large amounts of organic matter (biodegradable, but also refractory to biodegradation), as well as ammonia-nitrogen, small trace of some heavy metals, and inorganic salts. In order to investigate the surface water quality in the Reconquista river adjacent to the Norte III landfill, water samples both upstream and downstream the dumpsite are quarterly collected and analyzed for 43 parameters including organic matter, heavy metals, and inorganic salts, as required by the local standards. The objective of this study is to apply a water quality index that considers the leachate characteristics in order to determine the quality status of the watercourse through the landfill. The water pollution index method has been widely used in water quality assessments, particularly rivers, and it has played an increasingly important role in water resource management, since it provides a number simple enough for the public to understand, that states the overall water quality at a certain location and time. The chosen water quality index (ICA) is based on the values of six parameters: dissolved oxygen (in mg/l and percent saturation), temperature, biochemical oxygen demand (BOD5), ammonia-nitrogen and chloride (Cl-) concentration. The index 'ICA' was determined both upstream and downstream the Reconquista river, being the rating scale between 0 (very poor water quality) and 10 (excellent water quality). The monitoring results indicated that the water quality was unaffected by possible leachate runoff since the index scores upstream and downstream were ranked in the same category, although in general, most of the samples were classified as having poor water quality according to the index’s scale. The annual averaged ICA index scores (computed quarterly) were 4.9, 3.9, 4.4 and 5.0 upstream and 3.9, 5.0, 5.1 and 5.0 downstream the river during the study period between 2014 and 2017. Additionally, the water quality seemed to exhibit distinct seasonal variations, probably due to annual precipitation patterns in the study area. The ICA water quality index appears to be appropriate to evaluate landfill impacts since it accounts mainly for organic pollution and inorganic salts and the absence of heavy metals in the local leachate composition, however, the inclusion of other parameters could be more decisive in discerning the affected stream reaches from the landfill activities. A future work may consider adding to the index other parameters like total organic carbon (TOC) and total suspended solids (TSS) since they are present in the leachate in high concentrations.Keywords: landfill, leachate, surface water, water quality index
Procedia PDF Downloads 1406900 Thermal Performance of Fully Immersed Naturally Cooled Server
Authors: Yaser Al-Anii, Abdulmajeed Almaneea, Jonathan L. Summers, Harvey M. Thompson, Nikil Kapur
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The natural convection cooling system of a fully immersed server in a dielectric liquid is studied numerically. In the present case study, the dielectric liquid represents working fluid and it is in contact with server inside capsule. The capsule includes electronic component and fluid which can be modeled as saturated porous media. This medium follow Darcy flow regime and assumed to be in balance between its components. The study focus is on role of spatial parameters on thermal behavior of convective heat transfer. Based on server known unit, which is 1U, two parameters Ly and S are changed to test their effect. Meanwhile, wide-range of modified Rayleigh number, which is 0.5 to 300, are covered to better understand thermal performance. Navier-Stokes equations are used to model physical domain. Furthermore, successive over-relaxation and time marching techniques are used to solve momentum and energy equation. From obtained correlation, the in-between distance S is more effective on Nusselt number than distance to edge Ly by approximately 14%. In addition, as S increases, the average Nusselt number of the upper unit increases sharply, whereas the lower one keeps on the same level.Keywords: convective cooling of server, Darcy flow, liquid-immersed server, porous media
Procedia PDF Downloads 3926899 The Effect of Soil in the Allelopathic Potential of Artemisia herba-alba and Oudneya africana Crude Powder on Growth of Weeds
Authors: Salhi Nesrine, Salama M. El-Darier, Halilat M. El-Taher
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The present study aimed to investigate the effect of two type of soil (clay and sandy soils) in the potential allelopathic effects of Artemisia herba-alba, Oudneya africana crude powder on some growth parameters and phytomass of two weeds (Bromus tectorum and Melilotus indica) under laboratory conditions (pot experiment). The experimental findings have reported that the donor species crude powder concentrations were suppressing to shoot length (SL), root length (RL), fresh and dry weight of shoot and root (SFw, RFw, SDw and RDw, respectively and the leaf number (LN)) in both soil types and caused a gradual reduction particularly when they are high. However, the reduction degree was varied and species, concentration dependent. The suppressive effect of all the eight donors on the two weedy species was in the following order Bromus tectorum> Melilotus indica. Generally, the growth parameters of two recipient species were significantly decreased with the increase of each of the donor species crude powder concentration levels. Concerning the type of sol the t-test indicated that the difference was insignificant between clay and sandy soils.Keywords: allelopathy, soil, Artemisia herba-alba, Oudneya africana, growth, weeds
Procedia PDF Downloads 3546898 Gammarus: Asellus Ratio as an Index of Organic Pollution: A Case Study in Markeaton, Kedleston Hall, and Allestree Park Lakes Derby, UK
Authors: Usman Bawa
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Macro-invertebrates have been used to monitor organic pollution in rivers and streams. Several biotic indices based on macro-invertebrates have been developed over the years including the Biological Monitoring Working Party (BMWP). A new biotic index, the Gammarus:Asellus ratio has been recently proposed as an index of organic pollution. This study tested the validity of the Gammarus:Asellus ratio as an index of organic pollution, by examining the relationship between the Gammarus:Asellus ratio and physical-chemical parameters, and other biotic indices such as BMWP and, Average Score Per Taxon (ASPT) from lakes and streams at Markeaton Park, Allestree Park, and Kedleston Hall, Derbyshire. Macro invertebrates were sampled using the standard five-minute kick sampling techniques physical and chemical environmental variables were obtained based on standard sampling techniques. Eighteen sites were sampled, six sites from Markeaton Park (three sites across the stream and three sites across the lake). Six sites each were also sampled from Allestree Park and Kedleston Hall lakes. The Gammarus:Asellus ratio showed an opposite significant positive correlations with parameters indicative of organic pollution such as the level of nitrates, phosphates, and calcium and also revealed a negatively significant correlations with other biotic indices (BMWP/ASPT). The BMWP score correlated positively significantly with some water quality parameters such as dissolved oxygen and flow rate, but revealed no correlations with other chemical environmental variables. The BMWP score was significantly higher in the stream than the lake in Markeaton Park, also The ASPT scores appear to be significantly higher in the upper Lakes than the middle and lower lakes. This study has further strengthened the use of BMWP/ASPT score as an index of organic pollution. But, additional application is required to validate the use of Gammarus:Asellus as a rapid bio monitoring tool.Keywords: Asellus, biotic index, Gammarus, macro invertebrates, organic pollution
Procedia PDF Downloads 3346897 Nitrification and Denitrification Kinetic Parameters of a Mature Sanitary Landfill Leachate
Authors: Tânia F. C. V. Silva, Eloísa S. S. Vieira, João Pinto da Costa, Rui A. R. Boaventura, Vitor J. P. Vilar
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Sanitary landfill leachates are characterized as a complex mixture of diverse organic and inorganic contaminants, which are usually removed by combining different treatment processes. Due to its simplicity, reliability, high cost-effectiveness and high nitrogen content (mostly under the ammonium form) inherent in this type of effluent, the activated sludge biological process is almost always applied in leachate treatment plants (LTPs). The purpose of this work is to assess the effect of the main nitrification and denitrification variables on the nitrogen's biological removal, from mature leachates. The leachate samples were collected after an aerated lagoon, at a LTP nearby Porto, presenting a high amount of dissolved organic carbon (1.0-1.3 g DOC/L) and ammonium nitrogen (1.1-1.7 g NH4+-N/L). The experiments were carried out in a 1-L lab-scale batch reactor, equipped with a pH, temperature and dissolved oxygen (DO) control system, in order to determine the reaction kinetic constants at unchanging conditions. The nitrification reaction rate was evaluated while varying the (i) operating temperature (15, 20, 25 and 30ºC), (ii) DO concentration interval (0.5-1.0, 1.0-2.0 and 2.0-4.0 mg/L) and (iii) solution pH (not controlled, 7.5-8.5 and 6.5-7.5). At the beginning of most assays, it was verified that the ammonium stripping occurred simultaneously to the nitrification, reaching up to 37% removal of total dissolved nitrogen. The denitrification kinetic constants and the methanol consumptions were calculated for different values of (i) volatile suspended solids (VSS) content (25, 50 and 100 mL of centrifuged sludge in 1 L solution), (ii) pH interval (6.5-7.0, 7.5-8.0 and 8.5-9.0) and (iii) temperature (15, 20, 25 and 30ºC), using effluent previously nitrified. The maximum nitrification rate obtained was 38±2 mg NH4+-N/h/g VSS (25ºC, 0.5-1.0 mg O2/L, pH not controlled), consuming 4.4±0.3 mg CaCO3/mg NH4+-N. The highest denitrification rate achieved was 19±1 mg (NO2--N+NO3--N)/h/g VSS (30ºC, 50 mL of sludge and pH between 7.5 and 8.0), with a C/N consumption ratio of 1.1±0.1 mg CH3OH/mg (NO2--N+NO3--N) and an overall alkalinity production of 3.7±0.3 mg CaCO3/mg (NO2--N+NO3--N). The denitrification process showed to be sensitive to all studied parameters, while the nitrification reaction did not suffered significant change when DO content was changed.Keywords: mature sanitary landfill leachate, nitrogen removal, nitrification and denitrification parameters, lab-scale activated sludge biological reactor
Procedia PDF Downloads 2696896 Oryzanol Recovery from Rice Bran Oil: Adsorption Equilibrium Models Through Kinetics Data Approachments
Authors: A.D. Susanti, W. B. Sediawan, S.K. Wirawan, Budhijanto, Ritmaleni
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Oryzanol content in rice bran oil (RBO) naturally has high antioxidant activity. Its reviewed has several health properties and high interested in pharmacy, cosmetics, and nutrition’s. Because of the low concentration of oryzanol in crude RBO (0.9-2.9%) then its need to be further processed for practical usage, such as via adsorption process. In this study, investigation and adjustment of adsorption equilibrium models were conducted through the kinetic data approachments. Mathematical modeling on kinetics of batch adsorption of oryzanol separation from RBO has been set-up and then applied for equilibrium results. The size of adsorbent particles used in this case are usually relatively small then the concentration in the adsorbent is assumed to be not different. Hence, the adsorption rate is controlled by the rate of oryzanol mass transfer from the bulk fluid of RBO to the surface of silica gel. In this approachments, the rate of mass transfer is assumed to be proportional to the concentration deviation from the equilibrium state. The equilibrium models applied were Langmuir, coefficient distribution, and Freundlich with the values of the parameters obtained from equilibrium results. It turned out that the models set-up can quantitatively describe the experimental kinetics data and the adjustment of the values of equilibrium isotherm parameters significantly improves the accuracy of the model. And then the value of mass transfer coefficient per unit adsorbent mass (kca) is obtained by curve fitting.Keywords: adsorption equilibrium, adsorption kinetics, oryzanol, rice bran oil
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