Search results for: solution approaches
Commenced in January 2007
Frequency: Monthly
Edition: International
Paper Count: 9023

Search results for: solution approaches

8513 Preparation and Characterization of Titania-Coated Glass Fibrous Filters Using Aqueous Peroxotitanium Acid Solution

Authors: Ueda Honoka, Yasuo Hasegawa, Fumihiro Nishimura, Jae-Ho Kim, Susumu Yonezawa

Abstract:

Aqueous peroxotitanium acid solution prepared from the TiO₂ fluorinated by F₂ gas was used for the TiO₂ coating on glass fibrous filters in this study. The coating of TiO₂ on the surface of glass fibers was carried out at 120℃ and for 15 min ~ 24 h with aqueous peroxotitanium acid solution using a hydrothermal synthesis autoclave reactor. The morphology TiO₂ coating layer was largely dependent on the reaction time, as shown in the results of scanning electron microscopy and energy dispersive X-ray spectroscopy. Increasing the reaction times, the TiO₂ layer on the glass expanded uniformly. Moreover, the surface fluorination of glass fibers can promote the formation of the TiO₂ layer on the surface. The photocatalytic activity of prepared titania-coated glass fibrous filters was investigated by both the degradation test of methylene blue (MB) and the decomposition test of gaseous acetaldehyde. The MB decomposition ratio with fluorinated samples was about 95% for 30 min of UV irradiation time, and it was much higher than that (70%) with the untreated thing. The decomposition ratio (50%) of gaseous acetaldehyde with fluorinated samples was also higher than that (30%) with the untreated thing. Consequently, photocatalytic activity is enhanced by surface fluorination.

Keywords: aqueous peroxotitanium acid solution, titania-coated glass fibrous filters, photocatalytic activity, surface fluorination

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8512 Biomass Carbon Credit Estimation for Sustainable Urban Planning and Micro-climate Assessment

Authors: R. Niranchana, K. Meena Alias Jeyanthi

Abstract:

As a result of the present climate change dilemma, the energy balancing strategy is to construct a sustainable environment has become a top concern for researchers worldwide. The environment itself has always been a solution from the earliest days of human evolution. Carbon capture begins with its accurate estimation and monitoring credit inventories, and its efficient use. Sustainable urban planning with deliverables of re-use energy models might benefit from assessment methods like biomass carbon credit ranking. The term "biomass energy" refers to the various ways in which living organisms can potentially be converted into a source of energy. The approaches that can be applied to biomass and an algorithm for evaluating carbon credits are presented in this paper. The micro-climate evaluation using Computational Fluid dynamics was carried out across the location (1 km x1 km) at Dindigul, India (10°24'58.68" North, 77°54.1.80 East). Sustainable Urban design must be carried out considering environmental and physiological convection, conduction, radiation and evaporative heat exchange due to proceeding solar access and wind intensities.

Keywords: biomass, climate assessment, urban planning, multi-regression, carbon estimation algorithm

Procedia PDF Downloads 63
8511 Effective Affordable Housing Finance in Developing Economies: An Integration of Demand and Supply Solutions

Authors: Timothy Akinwande, Eddie Hui, Karien Dekker

Abstract:

Housing the urban poor remains a persistent challenge, despite evident research attention over many years. It is, therefore, pertinent to investigate affordable housing provision challenges with novel approaches. For innovative solutions to affordable housing constraints, it is apposite to thoroughly examine housing solutions vis a vis the key elements of the housing supply value chain (HSVC), which are housing finance, housing construction and land acquisition. A pragmatic analysis will examine affordable housing solutions from demand and supply perspectives to arrive at consolidated solutions from bilateral viewpoints. This study thoroughly examined informal housing finance strategies of the urban poor and diligently investigated expert opinion on affordable housing finance solutions. The research questions were: (1) What mutual grounds exist between informal housing finance solutions of the urban poor and housing expert solutions to affordable housing finance constraints in developing economies? (2) What are effective approaches to affordable housing finance in developing economies from an integrated demand - supply perspective? Semi-structured interviews were conducted in the 5 largest slums of Lagos, Nigeria, with 40 informal settlers for demand-oriented solutions, while focus group discussion and in-depth interviews were conducted with 12 housing experts in Nigeria for supply-oriented solutions. Following a rigorous thematic, content and descriptive analyses of data using NVivo and Excel, findings ascertained mutual solutions from both demand and supply standpoints that can be consolidated into more effective affordable housing finance solutions in Nigeria. Deliberate finance models that recognise and include the finance realities of the urban poor was found to be the most significant supply-side housing finance solution, representing 25.4% of total expert responses. Findings also show that 100% of sampled urban poor engage in vocations where they earn little irregular income or zero income, limiting their housing finance capacities and creditworthiness. Survey revealed that the urban poor are involved in community savings and employ microfinance institutions within the informal settlements to tackle their housing finance predicaments. These are informal finance models of the urban poor, revealing common grounds between demand and supply solutions for affordable housing financing. Effective, affordable housing approach will be to modify, institutionalise and incorporate the informal finance strategies of the urban poor into deliberate government policies. This consolidation of solutions from demand and supply perspectives can eliminate the persistent misalliance between affordable housing demand and affordable housing supply. This study provides insights into mutual housing solutions from demand and supply perspectives, and findings are informative for effective, affordable housing provision approaches in developing countries. This study is novel in consolidating affordable housing solutions from demand and supply viewpoints, especially in relation to housing finance as a key component of HSVC. The framework for effective, affordable housing finance in developing economies from a consolidated viewpoint generated in this study is significant for the achievement of sustainable development goals, especially goal 11 for sustainable, resilient and inclusive cities. Findings are vital for future housing studies.

Keywords: affordable housing, affordable housing finance, developing economies, effective affordable housing, housing policy, urban poor, sustainable development goal, sustainable affordable housing

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8510 Characteristics of Oil-In-Water Emulsion Stabilized with Pregelatinized Waxy Rice Starch

Authors: R. Yulianingsih, S. Gohtani

Abstract:

Characteristics of pregelatinized waxy rice starch (PWR) gelatinized at different temperatures (65, 75, and 85 °C, abbreviated as PWR 65, 75 and 85 respectively) and their emulsion-stabilizing properties at different starch concentrations (3, 5, 7, and 9%) were studied. The yield stress and consistency index value of PWR solution increased with an increase in starch concentration. The pseudoplasticity of PWR 65 solution increased and that for both PWR 75 and 85 solution decreased with an increase in starch concentration. Small angle X-ray scattering (SAXS) profiles analyzed by Kratky Plot indicated that PWR 65 is natively unfolded particles while PWR 75 and 85 are the globular particles. The characteristics of emulsions stabilized with PWR were influenced by the temperature of gelatinization process and starch concentration. Elevated concentration of starch decreased the value of yield stress and increased the consistency index. PWR 65 produce stable emulsion to creaming at starch concentrations more than 5%, while PWR 85 is able to produce stable emulsion to both creaming and coalescence of droplets.

Keywords: emulsion, gelatinization temperature, rheology, small-angle X-ray scattering, waxy rice starch

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8509 Extraction of Cellulose Nanocrystals from Soy Pods

Authors: Maycon dos Santos, Marivane Turim Koschevic, Karina Sayuri Ueda, Marcello Lima Bertuci, Farayde Matta Fackhouri, Silvia Maria Martelli

Abstract:

The use of cellulose nanocrystals as reinforcing agents in polymer nanocomposites is promising. In this study, we tested four different methods of mercerization were divided into two stages. The sample was treated in 5% NaOH solution for 30 minutes at 50 ° C in the first stage and 30vol H2O2 for 2 hours at 50 ° C in the second step, which showed better results. For the extraction of the sample obtained nanocrystals positive result was that the solution was treated with H2SO4 60% (w / w) for 1 hour at 50 ° C. The results were positive and showed that it is possible to extract CNC at low temperatures.

Keywords: soy pods, cellulose nanocrystals, temperature, acid concentration

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8508 The Role of DNA Evidence in Determining Paternity in India: A Study of Cases from the Legal and Scientific Perspective

Authors: Pratyusha Das

Abstract:

A paradigm shift has been noticed in the interpretation of DNA evidence for determining paternity. Sometimes DNA evidence has been accepted while sometimes it was rejected by the Indian Courts. Courts have forwarded various justifications for acceptance and rejection of such evidence through legal and scientific means. Laws have also been changed to accommodate the necessities of society. Balances between both the legal and scientific approaches are required, to make the best possible use of DNA evidence for the well-being of the society. Specifications are to be framed as to when such evidence can be used in the future by pointing out the pros and cons. Judicial trend is to be formulated to find out the present situation. The study of cases of superior courts of India using an analytical and theoretical approach is driving the questions regarding the shared identity of the legal and scientific approaches. To assimilate the differences between the two approaches, the basic differences between them have to be formulated. Revelations are required to access the favorable decisions using the DNA evidence. Reasons are to be forwarded for the unfavorable decisions and the approach preferred in such cases. The outcome of the two methods has to be assessed in relation to the parties to the dispute, the society at large, the researcher and from the judicial point of view. The dependability of the two methods is to be studied in relation to the justice delivery system. A highlight of the chronological study of cases along with the changes in the laws with the aid of presumptions will address the questions of necessity of a method according to the facts and situations. Address is required in this respect whether the legal and scientific forces converge somewhere pushing the traditional identification of paternity towards a fundamental change.

Keywords: cases, evidence, legal, scientific

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8507 Investigating Elastica and Post Buckling Behavior Columns Using the Modified Newmark Method

Authors: Seyed Amin Vakili, Sahar Sadat Vakili, Seyed Ehsan Vakili, Nader Abdoli Yazdi

Abstract:

The purpose of this article is to analyze the finite displacement of Columns by applying the Modified Newmark Method. This research will be performed on Columns subjected to compressive axial load, therefore the non-linearity of the geometry is also considered. If the considered strut is perfect, the governing differential equation contains a branching point in the solution path. Investigation into the Elastica is a part of generalizing the developed method. It presents the ability of the Modified Newmark Method in treating non-linear differential equations Derived from elastic strut stability problems. These include not only an approximate polynomial solution for the Elastica problems, but can also recognize the branching point and the stable solution. However, this investigation deals with the post-buckling response of elastic and pin ended columns subjected to central or equally eccentric axial loads.

Keywords: columns, structural modeling, structures & structural stability, loads

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8506 All Solution-Processed Organic Light Emitting Diode with Low Melting Point Alloy Encapsulation

Authors: Geon Bae, Cheol Hee Moon

Abstract:

Organic Light Emitting Diodes (OLEDs) are being developed rapidly as next-generation displays due to their self-luminous and flexible characteristics. OLEDs are highly susceptible to moisture and oxygen due to their structural properties. Thus, requiring a high level of encapsulation technology. Recently, encapsulation technology such as Thin Film Encapsulation (TFE) has been developed for OLED, but it is not perfect to prevent moisture permeation on the side. In this study, we propose OLED encapsulation method using Low melting Point Alloy (LMPA). The LMPA line was designed in square box shape on the outer edge of the device and was formed by screen printing method. To determine if LMPA has an effect on OLED, we fabricated solution processed OLEDs with a square-shaped LMPA line and evaluate the I-V-L characteristics of the OLEDs. Also, the resistance characteristic of the LMPA line was observed by repeatedly bending the LMPA line. It is expected that LMPA encapsulation will have a great advantage in shortening the process time and cost reduction.

Keywords: OLED, encapsulation, LMPA, solution process

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8505 Technical Assessment of Utilizing Electrical Variable Transmission Systems in Hybrid Electric Vehicles

Authors: Majid Vafaeipour, Mohamed El Baghdadi, Florian Verbelen, Peter Sergeant, Joeri Van Mierlo, Kurt Stockman, Omar Hegazy

Abstract:

The Electrical Variable Transmission (EVT), an electromechanical device, can be considered as an alternative solution to the conventional transmission system utilized in Hybrid Electric Vehicles (HEVs). This study present comparisons in terms of fuel consumption, power split, and state of charge (SoC) of an HEV containing an EVT to a conventional parallel topology and a series topology. To this end, corresponding simulations of these topologies are all performed in presence of control strategies enabling battery charge-sustaining and efficient power split. The power flow through the components of the vehicle are attained, and fuel consumption results of the considered cases are compared. The investigation of the results indicates utilizing EVT can provide significant added values in HEV configurations. The outcome of the current research paves its path for implementation of design optimization approaches on such systems in further research directions.

Keywords: Electrical Variable Transmission (EVT), Hybrid Electric Vehicle (HEV), parallel, series, modeling

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8504 Real Time Multi Person Action Recognition Using Pose Estimates

Authors: Aishrith Rao

Abstract:

Human activity recognition is an important aspect of video analytics, and many approaches have been recommended to enable action recognition. In this approach, the model is used to identify the action of the multiple people in the frame and classify them accordingly. A few approaches use RNNs and 3D CNNs, which are computationally expensive and cannot be trained with the small datasets which are currently available. Multi-person action recognition has been performed in order to understand the positions and action of people present in the video frame. The size of the video frame can be adjusted as a hyper-parameter depending on the hardware resources available. OpenPose has been used to calculate pose estimate using CNN to produce heap-maps, one of which provides skeleton features, which are basically joint features. The features are then extracted, and a classification algorithm can be applied to classify the action.

Keywords: human activity recognition, computer vision, pose estimates, convolutional neural networks

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8503 Nonlinear Modelling of Sloshing Waves and Solitary Waves in Shallow Basins

Authors: Mohammad R. Jalali, Mohammad M. Jalali

Abstract:

The earliest theories of sloshing waves and solitary waves based on potential theory idealisations and irrotational flow have been extended to be applicable to more realistic domains. To this end, the computational fluid dynamics (CFD) methods are widely used. Three-dimensional CFD methods such as Navier-Stokes solvers with volume of fluid treatment of the free surface and Navier-Stokes solvers with mappings of the free surface inherently impose high computational expense; therefore, considerable effort has gone into developing depth-averaged approaches. Examples of such approaches include Green–Naghdi (GN) equations. In Cartesian system, GN velocity profile depends on horizontal directions, x-direction and y-direction. The effect of vertical direction (z-direction) is also taken into consideration by applying weighting function in approximation. GN theory considers the effect of vertical acceleration and the consequent non-hydrostatic pressure. Moreover, in GN theory, the flow is rotational. The present study illustrates the application of GN equations to propagation of sloshing waves and solitary waves. For this purpose, GN equations solver is verified for the benchmark tests of Gaussian hump sloshing and solitary wave propagation in shallow basins. Analysis of the free surface sloshing of even harmonic components of an initial Gaussian hump demonstrates that the GN model gives predictions in satisfactory agreement with the linear analytical solutions. Discrepancies between the GN predictions and the linear analytical solutions arise from the effect of wave nonlinearities arising from the wave amplitude itself and wave-wave interactions. Numerically predicted solitary wave propagation indicates that the GN model produces simulations in good agreement with the analytical solution of the linearised wave theory. Comparison between the GN model numerical prediction and the result from perturbation analysis confirms that nonlinear interaction between solitary wave and a solid wall is satisfactorilly modelled. Moreover, solitary wave propagation at an angle to the x-axis and the interaction of solitary waves with each other are conducted to validate the developed model.

Keywords: Green–Naghdi equations, nonlinearity, numerical prediction, sloshing waves, solitary waves

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8502 Parkinson’s Disease Detection Analysis through Machine Learning Approaches

Authors: Muhtasim Shafi Kader, Fizar Ahmed, Annesha Acharjee

Abstract:

Machine learning and data mining are crucial in health care, as well as medical information and detection. Machine learning approaches are now being utilized to improve awareness of a variety of critical health issues, including diabetes detection, neuron cell tumor diagnosis, COVID 19 identification, and so on. Parkinson’s disease is basically a disease for our senior citizens in Bangladesh. Parkinson's Disease indications often seem progressive and get worst with time. People got affected trouble walking and communicating with the condition advances. Patients can also have psychological and social vagaries, nap problems, hopelessness, reminiscence loss, and weariness. Parkinson's disease can happen in both men and women. Though men are affected by the illness at a proportion that is around partial of them are women. In this research, we have to get out the accurate ML algorithm to find out the disease with a predictable dataset and the model of the following machine learning classifiers. Therefore, nine ML classifiers are secondhand to portion study to use machine learning approaches like as follows, Naive Bayes, Adaptive Boosting, Bagging Classifier, Decision Tree Classifier, Random Forest classifier, XBG Classifier, K Nearest Neighbor Classifier, Support Vector Machine Classifier, and Gradient Boosting Classifier are used.

Keywords: naive bayes, adaptive boosting, bagging classifier, decision tree classifier, random forest classifier, XBG classifier, k nearest neighbor classifier, support vector classifier, gradient boosting classifier

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8501 Building a Model for Information Literacy Education in School Settings

Authors: Tibor Koltay

Abstract:

Among varied new literacies, information literacy is not only the best-known one but displays numerous models and frameworks. Nonetheless, there is still a lack of its complex theoretical model that could be applied to information literacy education in public (K12) education, which often makes use of constructivist approaches. This paper aims to present the main features of such a model. To develop a complex model, the literature and practice of phenomenographic and sociocultural theories, as well as discourse analytical approaches to information literacy, have been reviewed. Besides these constructivist and expressive based educational approaches, the new model is intended to include the innovation of coupling them with a cognitive model that takes developing informational and operational knowledge into account. The convergences between different literacies (information literacy, media literacy, media and information literacy, and data literacy) were taken into account, as well. The model will also make use of a three-country survey that examined secondary school teachers’ attitudes to information literacy. The results of this survey show that only a part of the respondents feel properly prepared to teach information literacy courses, and think that they can teach information literacy skills by themselves, while they see a librarian as an expert in educating information literacy. The use of the resulting model is not restricted to enhancing theory. It is meant to raise the level of awareness about information literacy and related literacies, and the next phase of the model’s development will be a pilot study that verifies the usefulness of the methodology for practical information literacy education in selected Hungarian secondary schools.

Keywords: communication, data literacy, discourse analysis, information literacy education, media and information literacy media literacy, phenomenography, public education, sociocultural theory

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8500 Determination of Verapamil Hydrochloride in the Tablet and Injection Solution by the Verapamil-Sensitive Electrode and Possibilities of Application in Pharmaceutical Analysis

Authors: Faisal A. Salih, V. V. Egorov

Abstract:

Verapamil is a drug used in medicine for arrhythmia, angina, and hypertension as a calcium channel blocker. In this study, a Verapamil-selective electrode was prepared, and the concentrations of the components in the membrane were as follows: PVC (32.8 wt %), O-NPhOE (66.6 wt %), and KTPClPB (0.6 wt % or approximately 0.01 M). The inner solution containing verapamil hydrochloride 1 x 10⁻³ M was introduced, and the electrodes were conditioned overnight in 1 x 10⁻³ M verapamil hydrochloride solution in 1 x 10⁻³ M orthophosphoric acid. These studies have demonstrated that O-NPhOE and KTPClPB are the best plasticizers and ion exchangers, while both direct potentiometry and potentiometric titration methods can be used for the determination of verapamil hydrochloride in tablets and injection solutions. Normalized weights of verapamil per tablet (80.4±0.2, 80.7±0.2, 81.0±0.4 mg) were determined by direct potentiometry and potentiometric titration, respectively. Weights of verapamil per average tablet weight determined by the methods of direct potentiometry and potentiometric titration were" 80.4±0.2, 80.7±0.2 mg determined for the same set of tablets, respectively. The masses of verapamil in solutions for injection, determined by direct potentiometry for two ampoules from one set, were (5.00±0.015, 5.004±0.006) mg. In all cases, good reproducibility and excellent correspondence with the declared quantities were observed.

Keywords: verapamil, potentiometry, ion-selective electrode, lipophilic physiologically active amines

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8499 Value from Environmental and Cultural Perspectives or Two Sides of the Same Coin

Authors: Vilem Paril, Dominika Tothova

Abstract:

This paper discusses the value theory in cultural heritage and the value theory in environmental economics. Two economic views of the value theory are compared within the field of cultural heritage maintenance and within the field of the environment. The main aims are to find common features in these two differently structured theories under the layer of differently defined terms as well as really differing features of these two approaches, to clear the confusion which stems from different terminology as in fact these terms capture the same aspects of reality and to show possible inspiration these two perspectives can offer one another. Another aim is to present these two value systems in one value framework. First, important moments of the value theory from the economic perspective are presented, leading to the marginal revolution of (not only) the Austrian School. Then the theory of value within cultural heritage and environmental economics are explored. Finally, individual approaches are compared and their potential mutual inspiration searched for.

Keywords: cultural heritage, environmental economics, existence value, value theory

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8498 The Improved Laplace Homotopy Perturbation Method for Solving Non-integrable PDEs

Authors: Noufe H. Aljahdaly

Abstract:

The Laplace homotopy perturbation method (LHPM) is an approximate method that help to compute the approximate solution for partial differential equations. The method has been used for solving several problems in science. It requires the initial condition, so it solves the initial value problem. In physics, when some important terms are taken in account, we may obtain non-integrable partial differential equations that do not have analytical integrals. This type of PDEs do not have exact solution, therefore, we need to compute the solution without initial condition. In this work, we improved the LHPM to be able to solve non-integrable problem, especially the damped PDEs, which are the PDEs that include a damping term which makes the PDEs non-integrable. We improved the LHPM by setting a perturbation parameter and an embedding parameter as the damping parameter and using the initial condition for damped PDE as the initial condition for non-damped PDE.

Keywords: non-integrable PDEs, modified Kawahara equation;, laplace homotopy perturbation method, damping term

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8497 Robust Optimisation Model and Simulation-Particle Swarm Optimisation Approach for Vehicle Routing Problem with Stochastic Demands

Authors: Mohanad Al-Behadili, Djamila Ouelhadj

Abstract:

In this paper, a specific type of vehicle routing problem under stochastic demand (SVRP) is considered. This problem is of great importance because it models for many of the real world vehicle routing applications. This paper used a robust optimisation model to solve the problem along with the novel Simulation-Particle Swarm Optimisation (Sim-PSO) approach. The proposed Sim-PSO approach is based on the hybridization of the Monte Carlo simulation technique with the PSO algorithm. A comparative study between the proposed model and the Sim-PSO approach against other solution methods in the literature has been given in this paper. This comparison including the Analysis of Variance (ANOVA) to show the ability of the model and solution method in solving the complicated SVRP. The experimental results show that the proposed model and Sim-PSO approach has a significant impact on the obtained solution by providing better quality solutions comparing with well-known algorithms in the literature.

Keywords: stochastic vehicle routing problem, robust optimisation model, Monte Carlo simulation, particle swarm optimisation

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8496 On the Strong Solutions of the Nonlinear Viscous Rotating Stratified Fluid

Authors: A. Giniatoulline

Abstract:

A nonlinear model of the mathematical fluid dynamics which describes the motion of an incompressible viscous rotating fluid in a homogeneous gravitational field is considered. The model is a generalization of the known Navier-Stokes system with the addition of the Coriolis parameter and the equations for changeable density. An explicit algorithm for the solution is constructed, and the proof of the existence and uniqueness theorems for the strong solution of the nonlinear problem is given. For the linear case, the localization and the structure of the spectrum of inner waves are also investigated.

Keywords: Galerkin method, Navier-Stokes equations, nonlinear partial differential equations, Sobolev spaces, stratified fluid

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8495 Modelling of Air-Cooled Adiabatic Membrane-Based Absorber for Absorption Chillers Using Low Temperature Solar Heat

Authors: M. Venegas, M. De Vega, N. García-Hernando

Abstract:

Absorption cooling chillers have received growing attention over the past few decades as they allow the use of low-grade heat to produce the cooling effect. The combination of this technology with solar thermal energy in the summer period can reduce the electricity consumption peak due to air-conditioning. One of the main components, the absorber, is designed for simultaneous heat and mass transfer. Usually, shell and tubes heat exchangers are used, which are large and heavy. Cooling water from a cooling tower is conventionally used to extract the heat released during the absorption and condensation processes. These are clear inconvenient for the generalization of the absorption technology use, limiting its benefits in the contribution to the reduction in CO2 emissions, particularly for the H2O-LiBr solution which can work with low heat temperature sources as provided by solar panels. In the present work a promising new technology is under study, consisting in the use of membrane contactors in adiabatic microchannel mass exchangers. The configuration here proposed consists in one or several modules (depending on the cooling capacity of the chiller) that contain two vapour channels, separated from the solution by adjacent microporous membranes. The solution is confined in rectangular microchannels. A plastic or synthetic wall separates the solution channels between them. The solution entering the absorber is previously subcooled using ambient air. In this way, the need for a cooling tower is avoided. A model of the configuration proposed is developed based on mass and energy balances and some correlations were selected to predict the heat and mass transfer coefficients. The concentration and temperatures along the channels cannot be explicitly determined from the set of equations obtained. For this reason, the equations were implemented in a computer code using Engineering Equation Solver software, EES™. With the aim of minimizing the absorber volume to reduce the size of absorption cooling chillers, the ratio between the cooling power of the chiller and the absorber volume (R) is calculated. Its variation is shown along the solution channels, allowing its optimization for selected operating conditions. For the case considered the solution channel length is recommended to be lower than 3 cm. Maximum values of R obtained in this work are higher than the ones found in optimized horizontal falling film absorbers using the same solution. Results obtained also show the variation of R and the chiller efficiency (COP) for different ambient temperatures and desorption temperatures typically obtained using flat plate solar collectors. The configuration proposed of adiabatic membrane-based absorber using ambient air to subcool the solution is a good technology to reduce the size of the absorption chillers, allowing the use of low temperature solar heat and avoiding the need for cooling towers.

Keywords: adiabatic absorption, air-cooled, membrane, solar thermal energy

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8494 Ab initio Simulation of Y2O3 -Doped Cerium Using Heyd–Scuseria–Ernzerhof HSE Hybrid Functional and DFT+U Approaches

Authors: M. Taibeche, L. Guerbous, M. Kechouane, R. Nedjar, T. Zergoug

Abstract:

It is known that Y2O3 Material is the most important among the sesquioxides within the general class of refractory ceramics. Indeed, this compound has many applications such as sintering optical windows, components for rare-earth doped lasers as well as inorganic scintillators in the detection scintillation. In particular Eu2+ and Ce3+ are favored dopants in many the scintillators due to its allowed optical 5d-4f transition. In this work, we present new results concerning structural and electronic properties of Ce-doped Y2O3, investigated by density functional theory (DFT), using the Heyd–Scuseria–Ernzerhof (HSE) hybrid functional and DFT+U two approaches. When, we compared the results from the two methods we obtain a good agreement available experimental data. Furthermore, the effect of cerium on the material has also been studied and discussed in the same framework.

Keywords: DFT, vienne ab initio simulation packages, scintillators, Heyd–Scuseria–Ernzerhof (HSE) hybrid functional

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8493 On the Blocked-off Finite-Volume Radiation Solutions in a Two-Dimensional Enclosure

Authors: Gyo Woo Lee, Man Young Kim

Abstract:

The blocked-off formulations for the analysis of radiative heat transfer are formulated and examined in order to find the solutions in a two-dimensional complex enclosure. The final discretization equations using the step scheme for spatial differencing practice are proposed with the additional source term to incorporate the blocked-off procedure. After introducing the implementation for inactive region into the general discretization equation, three different problems are examined to find the performance of the solution methods.

Keywords: radiative heat transfer, Finite Volume Method (FVM), blocked-off solution procedure, body-fitted coordinate

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8492 Intrusion Detection System Using Linear Discriminant Analysis

Authors: Zyad Elkhadir, Khalid Chougdali, Mohammed Benattou

Abstract:

Most of the existing intrusion detection systems works on quantitative network traffic data with many irrelevant and redundant features, which makes detection process more time’s consuming and inaccurate. A several feature extraction methods, such as linear discriminant analysis (LDA), have been proposed. However, LDA suffers from the small sample size (SSS) problem which occurs when the number of the training samples is small compared with the samples dimension. Hence, classical LDA cannot be applied directly for high dimensional data such as network traffic data. In this paper, we propose two solutions to solve SSS problem for LDA and apply them to a network IDS. The first method, reduce the original dimension data using principal component analysis (PCA) and then apply LDA. In the second solution, we propose to use the pseudo inverse to avoid singularity of within-class scatter matrix due to SSS problem. After that, the KNN algorithm is used for classification process. We have chosen two known datasets KDDcup99 and NSLKDD for testing the proposed approaches. Results showed that the classification accuracy of (PCA+LDA) method outperforms clearly the pseudo inverse LDA method when we have large training data.

Keywords: LDA, Pseudoinverse, PCA, IDS, NSL-KDD, KDDcup99

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8491 A Study of Seismic Design Approaches for Steel Sheet Piles: Hydrodynamic Pressures and Reduction Factors Using CFD and Dynamic Calculations

Authors: Helena Pera, Arcadi Sanmartin, Albert Falques, Rafael Rebolo, Xavier Ametller, Heiko Zillgen, Cecile Prum, Boris Even, Eric Kapornyai

Abstract:

Sheet piles system can be an interesting solution when dealing with harbors or quays designs. However, current design methods lead to conservative approaches due to the lack of specific basis of design. For instance, some design features still deal with pseudo-static approaches, although being a dynamic problem. Under this concern, the study particularly focuses on hydrodynamic water pressure definition and stability analysis of sheet pile system under seismic loads. During a seismic event, seawater produces hydrodynamic pressures on structures. Currently, design methods introduce hydrodynamic forces by means of Westergaard formulation and Eurocodes recommendations. They apply constant hydrodynamic pressure on the front sheet pile during the entire earthquake. As a result, the hydrodynamic load may represent 20% of the total forces produced on the sheet pile. Nonetheless, some studies question that approach. Hence, this study assesses the soil-structure-fluid interaction of sheet piles under seismic action in order to evaluate if current design strategies overestimate hydrodynamic pressures. For that purpose, this study performs various simulations by Plaxis 2D, a well-known geotechnical software, and CFD models, which treat fluid dynamic behaviours. Knowing that neither Plaxis nor CFD can resolve a soil-fluid coupled problem, the investigation imposes sheet pile displacements from Plaxis as input data for the CFD model. Then, it provides hydrodynamic pressures under seismic action, which fit theoretical Westergaard pressures if calculated using the acceleration at each moment of the earthquake. Thus, hydrodynamic pressures fluctuate during seismic action instead of remaining constant, as design recommendations propose. Additionally, these findings detect that hydrodynamic pressure contributes a 5% to the total load applied on sheet pile due to its instantaneous nature. These results are in line with other studies that use added masses methods for hydrodynamic pressures. Another important feature in sheet pile design is the assessment of the geotechnical overall stability. It uses pseudo-static analysis since the dynamic analysis cannot provide a safety calculation. Consequently, it estimates the seismic action. One of its relevant factors is the selection of the seismic reduction factor. A huge amount of studies discusses the importance of it but also about all its uncertainties. Moreover, current European standards do not propose a clear statement on that, and they recommend using a reduction factor equal to 1. This leads to conservative requirements when compared with more advanced methods. Under this situation, the study calibrates seismic reduction factor by fitting results from pseudo-static to dynamic analysis. The investigation concludes that pseudo-static analyses could reduce seismic action by 40-50%. These results are in line with some studies from Japanese and European working groups. In addition, it seems suitable to account for the flexibility of the sheet pile-soil system. Nevertheless, the calibrated reduction factor is subjected to particular conditions of each design case. Further research would contribute to specifying recommendations for selecting reduction factor values in the early stages of the design. In conclusion, sheet pile design still has chances for improving its design methodologies and approaches. Consequently, design could propose better seismic solutions thanks to advanced methods such as findings of this study.

Keywords: computational fluid dynamics, hydrodynamic pressures, pseudo-static analysis, quays, seismic design, steel sheet pile

Procedia PDF Downloads 121
8490 Stripping of Flavour-Active Compounds from Aqueous Food Streams: Effect of Liquid Matrix on Vapour-Liquid Equilibrium in a Beer-Like Solution

Authors: Ali Ammari, Karin Schroen

Abstract:

In brewing industries, stripping is a downstream process to separate volatiles from beer. Due to physiochemical similarities between flavour components, the selectivity of this method is not favourable. Besides, the presence of non-volatile compounds such as proteins and carbohydrates may affect the separation of flavours due to their retaining properties. By using a stripping column with structured packing coupled with a gas chromatography, in this work, the overall mass transfer coefficient along with their corresponding equilibrium data was investigated for a model solution consist of water, ethanol, ethyl acetate and isoamyl acetate. Static headspace analysis also was employed to derive equilibrium data for flavours in the presence of beer dry matter. As it was expected ethanol and dry matter showed retention properties; however, the effect of viscosity in mass transfer coefficient was discarded due to the fact that the viscosity of solution decreased during stripping. The effect of ethanol and beer dry matter were mapped to be used for designing stripping could.

Keywords: flavour, headspace, Henry’s coefficient, mass transfer coefficient, stripping

Procedia PDF Downloads 173
8489 Integrating Environmental and Ecological Justice for the Sustainable Development of Smart Cities: A Normative Eco Framework

Authors: Thomas Benson

Abstract:

This paper leverages theoretical insights into two different justice approaches – environmental justice and ecological justice – to examine the effectiveness of sustainable development within smart cities and related smart city technology initiatives. Through theoretical development, the author seeks to establish an Eco Framework for smart cities and urban sustainable development. In turn, this paper aims to proffer the notion that there are ecologically sustainable ways in which smart cities can get smarter, and that such strategies can be compatible with ecological justice and environmental justice. Ultimately, a single conceptual framework is put forward to integrate the above approaches and concepts with normative prescriptions, which can serve researchers in the continued examination of smart cities and policymakers in their sustainable development of smart cities.

Keywords: ecological justice, environmental justice, normative framework, smart cities, sustainable development

Procedia PDF Downloads 155
8488 Identification of the Most Effective Dosage of Clove Oil Solution as an Alternative for Synthetic Anaesthetics on Zebrafish (Danio rerio)

Authors: D. P. N. De Silva, N. P. P. Liyanage

Abstract:

Zebrafish (Danio rerio) in the family Cyprinidae, is a tropical freshwater fish widely used as a model organism in scientific research. Use of effective and economical anaesthetic is very important when handling fish. Clove oil (active ingredient: eugenol) was identified as a natural product which is safer and economical compared to synthetic chemicals like methanesulfonate (MS-222). Therefore, the aim of this study was to identify the most effective dosage of clove oil solution as an anaesthetic on mature Zebrafish. Clove oil solution was prepared by mixing pure clove oil with 94% ethanol at a ratio of 1:9 respectively. From that solution, different volumes were selected as (0.4 ml, 0.6 ml and 0.8 ml) and dissolved in one liter of conditioned water (dosages : 0.4 ml/L, 0.6 ml/L and 0.8 ml/L). Water quality parameters (pH, temperature and conductivity) were measured before and after adding clove oil solution. Mature Zebrafish with similar standard length (2.76 ± 0.1 cm) and weight (0.524 ± 0.1 g) were selected for this experiment. Time taken for loss of equilibrium (initiation phase) and complete loss of movements including opercular movement (anaesthetic phase) were measured. To detect the efficacy on anaesthetic recovery, time taken to begin opercular movements (initiation of recovery phase) until swimming (post anaesthetic phase) were observed. The results obtained were analyzed according to the analysis of variance (ANOVA) and Tukeys’ method using SPSS version 17.0 at 95% confidence interval (p<0.5). According to the results, there was no significant difference at the initiation phase of anaesthesia in all three doses though the time taken was varied from 0.14 to 0.41 minutes. Mean value of the time taken to complete the anaesthetic phase at 0.4 ml/L dosage was significantly different with 0.6 ml/L and 0.8 ml/L dosages independently (p=0.01). There was no significant difference among recovery times at all dosages but 0.8 ml/L dosage took longer time compared to 0.6 ml/L dosage. The water quality parameters (pH and temperature) were stable throughout the experiment except conductivity, which increased with the higher dosage. In conclusion, the best dosage need to anaesthetize Zebrafish using clove oil solution was 0.6 ml/L due to its fast initiation of anaesthesia and quick recovery compared to the other two dosages. Therefore clove oil can be used as a good substitute for synthetic anaesthetics because of its efficacy at a lower dosage with higher safety at a low cost.

Keywords: anaesthetics, clove oil, zebrafish, Cyprinidae

Procedia PDF Downloads 690
8487 Water Reclamation from Synthetic Winery Wastewater Using a Fertiliser Drawn Forward Osmosis System Evaluating Aquaporin-Based Biomimetic and Cellulose Triacetate Forward Osmosis Membranes

Authors: Robyn Augustine, Irena Petrinic, Claus Helix-Nielsen, Marshall S. Sheldon

Abstract:

This study examined the performance of two commercial forward osmosis (FO) membranes; an aquaporin (AQP) based biomimetic membrane, and cellulose triacetate (CTA) membrane in a fertiliser is drawn forward osmosis (FDFO) system for the reclamation of water from synthetic winery wastewater (SWW) operated over 24 hr. Straight, 1 M KCl and 1 M NH₄NO₃ fertiliser solutions were evaluated as draw solutions in the FDFO system. The performance of the AQP-based biomimetic and CTA FO membranes were evaluated in terms of permeate water flux (Jw), reverse solute flux (Js) and percentage water recovery (Re). The average water flux and reverse solute flux when using 1 M KCl as a draw solution against controlled feed solution, deionised (DI) water, was 11.65 L/m²h and 3.98 g/m²h (AQP) and 6.24 L/m²h and 2.89 g/m²h (CTA), respectively. Using 1 M NH₄NO₃ as a draw solution yielded average water fluxes and reverse solute fluxes of 10.73 L/m²h and 1.31 g/m²h (AQP) and 5.84 L/m²h and 1.39 g/m²h (CTA), respectively. When using SWW as the feed solution and 1 M KCl and 1 M NH₄NO₃ as draw solutions, respectively, the average water fluxes observed were 8.15 and 9.66 L/m²h (AQP) and 5.02 and 5.65 L/m²h (CTA). Membrane water flux decline was the result of a combined decrease in the effective driving force of the FDFO system, reverse solute flux and organic fouling. Permeate water flux recoveries of between 84-98%, and 83-89% were observed for the AQP-based biomimetic and CTA membrane, respectively after physical cleaning by flushing was employed. The highest water recovery rate of 49% was observed for the 1 M KCl fertiliser draw solution with AQP-based biomimetic membrane and proved superior in the reclamation of water from SWW.

Keywords: aquaporin biomimetic membrane, cellulose triacetate membrane, forward osmosis, reverse solute flux, synthetic winery wastewater and water flux

Procedia PDF Downloads 144
8486 Thermodynamics of Aqueous Solutions of Organic Molecule and Electrolyte: Use Cloud Point to Obtain Better Estimates of Thermodynamic Parameters

Authors: Jyoti Sahu, Vinay A. Juvekar

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Electrolytes are often used to bring about salting-in and salting-out of organic molecules and polymers (e.g. polyethylene glycols/proteins) from the aqueous solutions. For quantification of these phenomena, a thermodynamic model which can accurately predict activity coefficient of electrolyte as a function of temperature is needed. The thermodynamics models available in the literature contain a large number of empirical parameters. These parameters are estimated using lower/upper critical solution temperature of the solution in the electrolyte/organic molecule at different temperatures. Since the number of parameters is large, inaccuracy can bethe creep in during their estimation, which can affect the reliability of prediction beyond the range in which these parameters are estimated. Cloud point of solution is related to its free energy through temperature and composition derivative. Hence, the Cloud point measurement can be used for accurate estimation of the temperature and composition dependence of parameters in the model for free energy. Hence, if we use a two pronged procedure in which we first use cloud point of solution to estimate some of the parameters of the thermodynamic model and determine the rest using osmotic coefficient data, we gain on two counts. First, since the parameters, estimated in each of the two steps, are fewer, we achieve higher accuracy of estimation. The second and more important gain is that the resulting model parameters are more sensitive to temperature. This is crucial when we wish to use the model outside temperatures window within which the parameter estimation is sought. The focus of the present work is to prove this proposition. We have used electrolyte (NaCl/Na2CO3)-water-organic molecule (Iso-propanol/ethanol) as the model system. The model of Robinson-Stokes-Glukauf is modified by incorporating the temperature dependent Flory-Huggins interaction parameters. The Helmholtz free energy expression contains, in addition to electrostatic and translational entropic contributions, three Flory-Huggins pairwise interaction contributions viz., and (w-water, p-polymer, s-salt). These parameters depend both on temperature and concentrations. The concentration dependence is expressed in the form of a quadratic expression involving the volume fractions of the interacting species. The temperature dependence is expressed in the form .To obtain the temperature-dependent interaction parameters for organic molecule-water and electrolyte-water systems, Critical solution temperature of electrolyte -water-organic molecules is measured using cloud point measuring apparatus The temperature and composition dependent interaction parameters for electrolyte-water-organic molecule are estimated through measurement of cloud point of solution. The model is used to estimate critical solution temperature (CST) of electrolyte water-organic molecules solution. We have experimentally determined the critical solution temperature of different compositions of electrolyte-water-organic molecule solution and compared the results with the estimates based on our model. The two sets of values show good agreement. On the other hand when only osmotic coefficients are used for estimation of the free energy model, CST predicted using the resulting model show poor agreement with the experiments. Thus, the importance of the CST data in the estimation of parameters of the thermodynamic model is confirmed through this work.

Keywords: concentrated electrolytes, Debye-Hückel theory, interaction parameters, Robinson-Stokes-Glueckauf model, Flory-Huggins model, critical solution temperature

Procedia PDF Downloads 361
8485 Using Analytical Hierarchy Process and TOPSIS Approaches in Designing a Finite Element Analysis Automation Program

Authors: Ming Wen, Nasim Nezamoddini

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Sophisticated numerical simulations like finite element analysis (FEA) involve a complicated process from model setup to post-processing tasks that require replication of time-consuming steps. Utilizing FEA automation program simplifies the complexity of the involved steps while minimizing human errors in analysis set up, calculations, and results processing. One of the main challenges in designing FEA automation programs is to identify user requirements and link them to possible design alternatives. This paper presents a decision-making framework to design a Python based FEA automation program for modal analysis, frequency response analysis, and random vibration fatigue (RVF) analysis procedures. Analytical hierarchy process (AHP) and technique for order preference by similarity to ideal solution (TOPSIS) are applied to evaluate design alternatives considering the feedback received from experts and program users.

Keywords: finite element analysis, FEA, random vibration fatigue, process automation, analytical hierarchy process, AHP, TOPSIS, multiple-criteria decision-making, MCDM

Procedia PDF Downloads 87
8484 Electro-oxidation of Catechol in the Presence of Nicotinamide at Different pH

Authors: M. A. Motin, M. A. Aziz, M. Hafiz Mia, M. A. Hasem

Abstract:

The redox behavior of catechol in the presence of nicotinamide as nucleophiles has been studied in aqueous solution with various pH values and different concentration of nicotinamide using cyclic voltammetry and differential pulse voltammetry. Cyclic voltammetry of catechol in buffer solution (3.00 < pH < 9.00) shows one anodic and corresponding cathodic peak which relates to the transformation of catechol to corresponding o-benzoquinone and vice versa within a quasi reversible two electron transfer process. Cyclic voltammogram of catechol in the presence of nicotinamide in buffer solution of pH 7, show one anodic peak in the first cycle of potential and on the reverse scan the corresponding cathodic peak slowly decreases and new peak is observed at less positive potential. In the second cycle of potential a new anodic peak is observed at less positive potential. This indicates that nicotinamide attached with catechol and formed adduct after first cycle of oxidation. The effect of pH of catechol in presence of nicotinamide was studied by varying pH from 3 to 11. The substitution reaction of catechol with nicotimamide is facilitated at pH 7. In buffer solution of higher pH (>9), the CV shows different pattern. The effect of concentration of nicotinamide was studied by 2mM to 100 mM. The maximum substitution reaction has been found for 50 mM of nicotinamide and of pH 7. The proportionality of the first scan anodic and cathodic peak currents with square root of scan rate suggests that the peak current of the species at each redox reaction is controlled by diffusion process. The current functions (1/v-1/2) of the anodic peak decreased with the increasing of scan rate demonstrated that the behavior of the substitution reaction is of ECE type.

Keywords: redox interaction, catechol, nicotinamide, substituion reaction, pH effect

Procedia PDF Downloads 437